ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • sediments  (42)
  • Gas chromatography  (32)
  • Immunocytochemistry  (29)
  • Rat  (27)
  • Springer  (125)
  • American Chemical Society
  • Cambridge University Press
  • 1980-1984  (125)
  • 1945-1949
  • 1925-1929
  • 1982  (125)
  • 1925
Collection
Keywords
Publisher
  • Springer  (125)
  • American Chemical Society
  • Cambridge University Press
  • Wiley-Blackwell  (63)
Years
  • 1980-1984  (125)
  • 1945-1949
  • 1925-1929
Year
  • 1
    Electronic Resource
    Electronic Resource
    Correlation of45Ca incorporation with maturation ameloblast morphology in the rat incisor (1982)
    Springer
    Calcified tissue international 34 (1982), S. 211-213 
    Details
    ISSN: 1432-0827
    Keywords: Rat ; incisor ; ameloblasts ; enamel ; 45Ca autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Rats were injected with45Ca and horseradish peroxidase to determine the patterns of45Ca incorporation into incisor enamel and the morphological types of the overlying maturation ameloblasts.45Ca autoradiography showed no differences in the patterns of incorporation into enamel between routinely embedded and freeze-dried specimens. Enamel overlaid by ruffle-ended ameloblasts was much more heavily labeled while that overlaid by smooth-ended ameloblasts showed only moderate labeling. The observations lend further support to the hypothesis that the ruffle-ended cells are very active in mineralizing enamel and that the smooth-ended cells are in a passive, restorative phase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411236
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Occurrence of actin-like protein in extracellular matrix vesicles (1982)
    Springer
    Calcified tissue international 34 (1982), S. 376-381 
    Details
    ISSN: 1432-0827
    Keywords: Matrix vesicles ; Bone ; Actin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Preliminary indications of the occurrence of actin and myosin in crude matrix vesicle preparations have been reported previously. In the present study extracellular matrix vesicles from rat alveolar bone were isolated. They were further purified by a sucrose density gradient. SDS-polyacrylamide gel electrophoresis of the purified vesicles revealed the presence of a polypeptide with a molecular weight of 43 K daltons and with electrophoretic mobility identical to that of blood platelet actin. The limited proteolysis of both 43 K dalton vesicular polypeptide and actin byStaphylococcus aureus-V8-protease revealed three fragments with identical electrophoretic mobility. In addition, the vesicular preparations inhibited the activity of DNase I, a property typical of actin monomers. Filamentous material extracted from matrix vesicles showed ultrastructural features of F-actin. Reaction of this material with heavy meromyosin resulted in arrowhead formation, which is characteristic of acto-heavy meromyosin. The occurrence of actin in extracellular matrix vesicles may account for their budding from the osteoblastic plasma membrane, their possible motility in the matrix, and maintenance of the spherical shape.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02411271
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Chemically modified teflon capillary columns for gas chromatography II. Solid surface effects in direct coated columns (1982)
    Springer
    Chromatographia 15 (1982), S. 641-644 
    Details
    ISSN: 1612-1112
    Keywords: Teflon capillary columns ; Chemically modified teflon ; Gas chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The preparation of teflon capillary columns employing direct coating of the stationary phase to the chemically modified teflon surface and the role of the chemically modified teflon in the separation mechanism are described. Two types of contributions from the modified teflon have been observed: nonspecific adsorption of the carbon surface and specific interactions of polar groups in the carbon skeleton. The use of polar liquid phases can eliminate adsorption due to the presence of polar groups in the modified teflon.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02279491
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Derivatization of amines with chloroformate esters for gas chromatographic analysis (1982)
    Springer
    Chromatographia 16 (1982), S. 60-62 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Amines ; Derivatization ; Chloroformate esters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The gas chromatographic analysis of amines after conversion to electron capture sensitive carbamates in two-phase systems has been studied. Hydrophilic compounds, for instance methylamine, are reacted with 2,2,2-trichloro-tert. butyl chloroformate. Quantitation below 10−7 M can be made by thermionic or electron capture detection. A hydrophobic amine, namely N,N-dimethyl-n-octylamine, was derivatized with 2,4,6-tribromophenyl chloroformate with addition of iodide ion to the aqueous phase. The favorable effect of iodide ion as well as the choice of pH and chloroformate ester is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258870
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Gas chromatography in open rectangular channels with large aspect ratios (1982)
    Springer
    Chromatographia 16 (1982), S. 98-102 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Rectangular channel ; Efficiency ; Capacity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Gas chromatographic experiments have been performed in a truly rectangular channel with a 60∶1 cross-sectional aspect ratio, constructed according to the field-flow fractionation technology. It is shown that the peak broadening is controlled by the thickness of the channel while the maximum load is determined by the largest cross-sectional dimension. However, even with its elongated configuration, the side walls contribute significantly to the band broadening of solutes with a high diffusivity. Good agreement is found between the experimental plate height data and the recent theoretical calculations of Golay [13] taking into account the side-wall effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258877
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Experimental measurement of sediment nitrification and denitrification in Hamilton Harbour, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 207-216 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; water column ; nitrification ; denitrification ; experiments ; modelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This research examines the role of sediment nitrification and denitrification in the nitrogen cycle of Hamilton Harbour. The Harbour is subject to large ammonia and carbon loadings from a waste-water treatment plant and from steel industries. Spring ammonia concentrations rapidly decrease from 4.5 to 0.5 mg 1−1, while spring nitrate concentrations increase from 1 to 2 mg l−1, by mid-summer. A three-layer sediment model was developed. The first layer is aerobic; in it, oxidation of organics and nitrification occurs. The second layer is for denitrification, and the third layer is for anaerobic processes. Ammonia sources for nitrification include diffusion from the water column, sources associated with the oxidation of organics, sources from denitrification and from anaerobic processes. Diffusion of oxygen, ammonia and nitrate across the sediment-water interface occurs. Temperature effects are modelled using the Arrhenius concept. A combination of zero-order kinetics for nitrate or ammonia consumption with diffusion results in a half-order reaction, with respect to the water column loss rate to sediments. From experimental measurement, the rate of nitrification is 200 mg N 1−1 sediment per day, while that of denitrification is 85 mg N 1–1 sediment per day at 20 °C. The Arrhenius activation energy is estimated as 15 000 cal/ mole-K and 17 000 cal/ mole-K for nitrification and denitrification, respectively, between 10 °C and 20 °C. Calculations of the flux of ammonia with the sediments, using the biofilm model, compare favourably with experimental observations. The ammonia flux from the water column is estimated to account for 20% of the observed decrease in water column stocks of ammonia, while the nitrate flux from the water column is estimated to account for 25% of the total nitrogen produced by the sediments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940111
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Particle size distribution and chemical parameters of the sediments of a shallow turbid impoundment (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 341-353 
    Details
    ISSN: 1573-5117
    Keywords: Impoundment ; sediments ; particle size ; major ions ; nutrients ; cation exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract As part of an ecosystem study of a small mesotrophic turbid impoundment in the semi-arid part of South Africa, an investigation was made of the particle size distribution, organic content and inorganic chemical composition of the sediment. Nine transects 50 m apart were made during February 1980. Sediments were sampled with an Eckman grab. The following analyses were made: size fractionation by wet sieving, cation exchange capacity, exchangeable Na, K, Ca, Mg and PO4, total P, and loss on ignition. From the results it was clear that the finer particles, in or near the original river bed, had higher cation exchange capacity, total P, exchangeable phosphorus and organic content. Littoral areas with avian habitat and extensive macrophyte vegetation, contained coarser sediments. Organic detritus apparently migrated to the deeper part of the impoundment. Sediments of lacustrine and fluvial origin were identified by means of the Passega classification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940124
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Spatial heterogeneity in whole lake sediments — towards a loading estimate (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 235-240 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; nutrients ; loading estimates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Studies of nutrient loadings, to shallow culturally eutrophied Alberta lakes, suggest internal inputs are significant. In this regard, estimation of bottom sediment P loads to Lake Wabamun (80 km2, 5.5 m $$\bar x$$ depth) were examined. Initially we determined the spatial variability in Total Organic Content (% loss on ignition) and Total Phosphorus, as indicators. Phosphorus fractions and biologically available phosphorus (BAP) were measured at specific stations. These data showed a very uniform distribution in sediment type with a Total Organic Content of 40.6 ± 3.3 (95% C.L.) at the west end, gradually declining to 26.3 ± 0.9 at the east end. Transects performed at routine monitoring stations indicate the representativeness of each station, e.g., station 2, 40.8 ± 1.3 (10 sites). One explanation of this uniformity is provided from210Pb analysis of shallow cores which indicate mixing to a depth of 16 cm. This is also thought to explain the mechanics of P loading to the water phase. Finally, Total Organic Content relates well to BAP (r2 = 0.80). It is hoped that this simple technique may well permit more precise extrapolation to whole lake BAP estimates at least on this lake.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940114
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Distribution and concentrations of naturally-occurring radionuclides in sediments in a uranium mining area of northern Saskatchewan, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 355-361 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; uranium ; radium ; radionuclides ; models
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Uranium mining and milling operations can contribute to environmental degradation through the increased release of naturally-occurring radionuclides. However, studies of the interactions of these radionuclides with freshwater sediments have been limited. The present study examined the vertical distribution of uranium, thorium, radium-226, polonium-210 and lead-210 in undisturbed sediment cores collected in the vicinity of mining, milling and exploration activities. Uranium levels in surface sediments ranged from 1.9 to 5650 µg g−1, Ra-226 from 〈0.1 to 480 pCi g−1 and Pb-210 from 0.8 to 931 pCi g−1 in the samples reported here, with the highest values occurring downstream of waste rock disposal areas. Concentrations usually decreased with depth, and there was little evidence of any strong effect of bioturbation on radionuclide profiles at the scale examined here. Mathematical models of uranium and radium-226 adsorption on and movement into the sediment were constructed, based on expected adsorption coefficients and estimated loading. The model predictions of radionuclide distribution with depth were qualitatively similar to those actually measured, but the predicted concentrations were generally lower than those observed, both in unaffected areas and in areas adjacent to uranium extraction activities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000035
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Lake sediments as recorders of geomagnetic field variations — applications to dating post-Glacial sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 587-596 
    Details
    ISSN: 1573-5117
    Keywords: dating ; sediments ; geomagnetic variations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Field and laboratory methods, developed to recover the record of past secular variations of geomagnetic declination and inclination carried by the remanent magnetization of some lake sediments, are described. Type curves, delineating these parameters through post-Glacial time, have now been constructed for Europe and east-central N. America. These curves, once established for any region, are useful for dating lake sediments from that region. The principal inclination features exhibited by the European curves can also be identified along the N. American curves with a delay of some 600 years, on average.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391973
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Stratigraphic and dynamic effects of sediment reworking by Great Lakes zoobenthos (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 611-622 
    Details
    ISSN: 1573-5117
    Keywords: zoobenthos ; Great Lakes ; sediments ; radionuclides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Recent sediments of the North American Great Lakes are inhabited by numerous species of macrobenthos which alter the physical and chemical properties of sediments and modify interface transport characteristics. Distributions of such radionuclides as cesium-137, lead-210, and isotopes of plutonium exhibit a zone of constant activity extending down from the sediment-water interface from 1 to 15 cm. Recent studies have confirmed that radiometrically determined mixed depths are consistent with the vertical distribution of oligochaete worms and the amphipod,Pontoporeia hoyi. Generally, 90% of the benthos are contained within the radiometrically defined mixed zone. Where comparisons are possible, rates of sediment reworking by ‘conveyor belt’ species are comparable to or exceed sedimentation rates. Systematic variations in the mixed depth occur within depositional basins with greatest depths tending to be associated with least consolidated, organically rich materials. A quantitative steady-state mixing model accounts satisfactorily for observed radioactivity and heavy metal profiles. Bioturbation appears to be an important process, limiting the resolution with which historical records of particle-associated contaminants may be reconstructed from sediment cores. As bioturbation serves to maintain contact of contaminated sediments with overlying water, this time may also characterize the long-term lake recovery for contaminants removed by burial. As the time varies with location, a mean for an entire lake is not well known, but is on the order of 20 years for Lake Huron.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391976
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Transport of iron and manganese in relation to the shapes of their concentration-depth profiles (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 463-471 
    Details
    ISSN: 1573-5117
    Keywords: iron ; manganese ; sediments ; water ; transport ; model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A model is presented which describes the transport of iron and manganese in the vicinity of a redox boundary. It is based on input of a particulate component, to form a point source, from which soluble species diffuse along a concentration gradient. The shapes of concentration-depth profiles in marine and freshwater sediments and water columns are reviewed and discussed in terms of the model. Transport, either entirely within a water column or within the sediment, may be simply treated because the rate of vertical transport can be regarded as constant. The discontinuity in the rate of vertical transport which occurs at the sediment-water interface can provide a complicated example of the model, especially when it coincides with the redox boundary. Authigenic mineral formation processes can modify the model, sometimes to such an extent that it becomes invalid. This is particularly true for soluble iron profiles in organically rich marine sediments. Sampling interval is critical to the resultant profile shape and must be relevant to the particular environment, e.g. metres in water columns and millimetres in sediments. The differences in the rates of reduction and oxidation of iron and manganese tend to modify both the position of the profile with respect to the redox-cline and its stage of development in a seasonally anoxic system. It is these factors which determine why most of the iron which reaches a sediment is permanently incorporated whereas manganese is re-released. This mechanism determines the average ratio of iron to manganese in sedimentary rocks. The development of peaked profile shapes in water columns implies that under certain conditions dissolved iron and manganese may be transported from the water column to the pore waters of the sediment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000044
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Deepwater sediments and trophic conditions in Florida lakes (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 597-602 
    Details
    ISSN: 1573-5117
    Keywords: eutrophication ; diagenesis ; sediments ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediment cores were taken from near maximum depth in 15 Florida lakes representing a wide range of trophic conditions. Chemical analyses of surface sediments showed Al, Fe, and Ca to be the most abundant elements in all samples, and the ratio of Al to Ca to be smaller for eutrophic lakes. Sediment organic matter increased with trophic state, as did the degree to which it was enriched in nitrogen. Corresponding sediment C/N ratios decreased with increasing lake trophic state and showed significant negative correlation with chlorophyll a, total N, and total P in the water column. Concentrations of sedimentary chlorophyll derivatives showed some relation to trophic state but differences in basin morphometry hinder its use as an inter-lake index of chlorophyll production.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000058
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Experimental measurement of sediment nitrification and denitrification in Hamilton Harbour, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 207-216 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; water column ; nitrification ; denitrification ; experiments ; modelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This research examines the role of sediment nitrification and denitrification in the nitrogen cycle of Hamilton Harbour. The Harbour is subject to large ammonia and carbon loadings from a waste-water treatment plant and from steel industries. Spring ammonia concentrations rapidly decrease from 4.5 to 0.5 mg 1−1, while spring nitrate concentrations increase from 1 to 2 mg l−1, by mid-summer. A three-layer sediment model was developed. The first layer is aerobic; in it, oxidation of organics and nitrification occurs. The second layer is for denitrification, and the third layer is for anaerobic processes. Ammonia sources for nitrification include diffusion from the water column, sources associated with the oxidation of organics, sources from denitrification and from anaerobic processes. Diffusion of oxygen, ammonia and nitrate across the sediment-water interface occurs. Temperature effects are modelled using the Arrhenius concept. A combination of zero-order kinetics for nitrate or ammonia consumption with diffusion results in a half-order reaction, with respect to the water column loss rate to sediments. From experimental measurement, the rate of nitrification is 200 mg N 1−1 sediment per day, while that of denitrification is 85 mg N 1–1 sediment per day at 20 °C. The Arrhenius activation energy is estimated as 15 000 cal/ mole-K and 17 000 cal/ mole-K for nitrification and denitrification, respectively, between 10 °C and 20 °C. Calculations of the flux of ammonia with the sediments, using the biofilm model, compare favourably with experimental observations. The ammonia flux from the water column is estimated to account for 20% of the observed decrease in water column stocks of ammonia, while the nitrate flux from the water column is estimated to account for 25% of the total nitrogen produced by the sediments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391937
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Introduction (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 1-1 
    Details
    ISSN: 1573-5117
    Keywords: symposium ; sediments ; freshwater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940091
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Transport of iron and manganese in relation to the shapes of their concentration-depth profiles (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 463-471 
    Details
    ISSN: 1573-5117
    Keywords: iron ; manganese ; sediments ; water ; transport ; model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A model is presented which describes the transport of iron and manganese in the vicinity of a redox boundary. It is based on input of a particulate component, to form a point source, from which soluble species diffuse along a concentration gradient. The shapes of concentration-depth profiles in marine and freshwater sediments and water columns are reviewed and discussed in terms of the model. Transport, either entirely within a water column or within the sediment, may be simply treated because the rate of vertical transport can be regarded as constant. The discontinuity in the rate of vertical transport which occurs at the sediment-water interface can provide a complicated example of the model, especially when it coincides with the redox boundary. Authigenic mineral formation processes can modify the model, sometimes to such an extent that it becomes invalid. This is particularly true for soluble iron profiles in organically rich marine sediments. Sampling interval is critical to the resultant profile shape and must be relevant to the particular environment, e.g. metres in water columns and millimetres in sediments. The differences in the rates of reduction and oxidation of iron and manganese tend to modify both the position of the profile with respect to the redox-cline and its stage of development in a seasonally anoxic system. It is these factors which determine why most of the iron which reaches a sediment is permanently incorporated whereas manganese is re-released. This mechanism determines the average ratio of iron to manganese in sedimentary rocks. The development of peaked profile shapes in water columns implies that under certain conditions dissolved iron and manganese may be transported from the water column to the pore waters of the sediment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391960
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Deepwater sediments and trophic conditions in Florida lakes (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 597-602 
    Details
    ISSN: 1573-5117
    Keywords: eutrophication ; diagenesis ; sediments ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediment cores were taken from near maximum depth in 15 Florida lakes representing a wide range of trophic conditions. Chemical analyses of surface sediments showed Al, Fe, and Ca to be the most abundant elements in all samples, and the ratio of Al to Ca to be smaller for eutrophic lakes. Sediment organic matter increased with trophic state, as did the degree to which it was enriched in nitrogen. Corresponding sediment C/N ratios decreased with increasing lake trophic state and showed significant negative correlation with chlorophylla, total N, and total P in the water column. Concentrations of sedimentary chlorophyll derivatives showed some relation to trophic state but differences in basin morphometry hinder its use as an inter-lake index of chlorophyll production.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391974
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Microbial metabolism in surface sediments and its role in the immobilization of phosphorus in oligotrophic lake sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 261-268 
    Details
    ISSN: 1573-5117
    Keywords: microbial metabolism ; phosphorus ; sediments ; oligotrophic lake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Rapid microbial metabolism and a large phosphorus uptake potential were observed in surface sediments of Lake George, New York. This sediment (termed the flocculent layer) also exhibited a phosphorus limited condition and a large reservoir of inorganic phosphorus associated with humic substances. These observations suggest that the empirically observed phosphorus retention in oligotrophic lake sediments may be promoted by a rapid cycling of phosphorus between microflora and its associated organic matter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391943
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Standardization of methods of analysis for heavy metals in sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 689-695 
    Details
    ISSN: 1573-5117
    Keywords: standardization ; heavy metals ; sediments ; base-line levels ; chemical partition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In studies of heavy metals in sediments, there is a need for standardization of the procedures for sample collection and preservation, chemical analyses and presentation of results. The method and depth of sampling depend on the aim of the investigation and on local sediment conditions, such as consistency of the sediment, rate of sedimentation, diagnetic processes and bioturbation. Therefore no general recommendations can be given in this respect. During collection and preservation, contamination and loss of constituents ust be avoided. In sediments, the best means for estimating total contents of metals is digestion with HF, in combination with strong acids. Other methods include X-ray fluorescence and neutron activation analyses. The use of HF is considered objectionable by some laboratories. A reasonable alternative is aqua regia. Because variations in granular composition affect metal contents, it is advisable to use the fraction 〈 63 μm for the analysis. Chemical partition of sediments provides an insight into the source of metallic constituents, and their pathways to deposition areas. A three-step extraction procedure, in the sequence 0.1 M hydroxylamine-HCl, H2O2 30% and HF, is proposed. Finally, attention is paid to the anthropogenic enrichment of metals in sediments. The establishment of base-line levels is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940158
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Zinc in water and sediments of two finnish lakes (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 155-160 
    Details
    ISSN: 1573-5117
    Keywords: heavy metals ; zinc ; lakes ; sediments ; pollution ; industrial load ; sedimentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The distribution of zinc in Lake Vanajavesi and Lake Mallasvesi, South Finland, was determined on the basis of water and sediment studies. Lake Vanajavesi is one of the most polluted of large inland lakes, in Finland. The zinc load comes mainly from industrial sources. Lake Mallasvesi, situated near Vanajavesi, is in almost natural condition. The water samples were taken by a Ruttner sampler. In collecting sediment samples, a freezing technique was used. The results of zinc analyses indicate that, during several winters, zinc has spread with waste water to different parts of L. Vanaja against the main course of flow. A close correlation between sedimentation of zinc and waste discharge from a textile factory was found in the present study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391931
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Standardization of methods of analysis for heavy metals in sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 689-695 
    Details
    ISSN: 1573-5117
    Keywords: standardization ; heavy metals ; sediments ; base-line levels ; chemical partition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In studies of heavy metals in sediments, there is a need for standardization of the procedures for sample collection and preservation, chemical analyses and presentation of results. The method and depth of sampling depend on the aim of the investigation and on local sediment conditions, such as consistency of the sediment, rate of sedimentation, diagnetic processes and bioturbation. Therefore no general recommendations can be given in this respect. During collection and preservation, contamination and loss of constituents ust be avoided. In sediments, the best means for estimating total contents of metals is digestion with HF, in combination with strong acids. Other methods include X-ray fluorescence and neutron activation analyses. The use of HF is considered objectionable by some laboratories. A reasonable alternative is aqua regia. Because variations in granular composition affect metal contents, it is advisable to use the fraction 〈 63 μm for the analysis. Chemical partition of sediments provides an insight into the source of metallic constituents, and their pathways to deposition areas. A three-step extraction procedure, in the sequence 0.1 M hydroxylamine-HCl, H2O2 30% and HF, is proposed. Finally, attention is paid to the anthropogenic enrichment of metals in sediments. The establishment of base-line levels is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391984
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Comparison of sediment energy-texture relationships in marine and lacustrine environments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 71-84 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; lakes ; seas ; oceans ; energy relationships ; population statistics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediments in the marine environment are generally subject to higher energy levels than those of lake systems, and lakes are virtually unaffected by tidal range which modifies beach structures formed in response to wave effects. However, despite different energy levels, the textural characteristics of both marine and lacustrine sediments are very similar. The main difference between marine and lacustrine facies is the depth range over which these characteristics remain consistent. In lakes, depth limitation may influence the development of surface waves and restrict textural distributions. Simple textural relationships can be used to describe comparable marine and lacustrine sedimentary conditions. Sediments which have been altered by post-depositional erosion, such as lag deposits, or by ice-drop or wind blown settlement, show comparable textural modifications. The settlement of silt and clay size particulates, in the marine environment and lakes, may differ slightly because of the chemical differences between salt and fresh water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940097
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    The fractionation of iron-phosphorus compounds in sediments studied by Mössbauer spectroscopy (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 697-700 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; Mössbauer spectroscopy ; iron ; phosphorus ; geochemistry ; analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Iron compounds of phosphorus form a large part of the phosphorus bound in sediments. Mössbauer spectroscopy is a technique that enables us to study, directly, chemical forms of iron in solid samples. Mössbauer spectroscopy allowed us to check, directly, the selectivity of the extraction scheme for soil phosphorus proposed by Chang & Jackson (1957), but only as far as the iron compounds are concerned. It appears that selectivity of the extraction method leaves much to be desired.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940159
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Model for instream regulation of radioisotopes and heavy metals in riverine waters subjected to a uranium mill discharge (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 175-188 
    Details
    ISSN: 1573-5117
    Keywords: simulation ; sediments ; radioisotopes ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the Athabaska sandstone region of northern Saskatchewan, mining and milling of uranium-bearing ore is subjecting, and will continue to subject, surface waters to inputs of soluble heavy metals and uranium and thorium decay series radioisotopes. A mathematical simulation model was developed to assess the role of riverine sediments in regulating soluble concentrations of heavy metals and radioisotopes released to the environment through treated mining and milling process effluents. Specific elements studied included As, Ni, Pb, U, and Ra-226. The model considered that diffusion into sediment porewater and adsorption by sediment particulates from sediment porewater were the two dominant mechanisms regulating sediment loading. Experiments indicated that the equilibrium adsorption behaviour of the heavy metals and radioisotopes studied could be adequately explained using a linear adsorption isotherm, over the range of concentrations expected in the environment. Experimentally determined linear isotherm slopes ranged from 200 ml g−1 to 21 000 ml gl. Diffusion into the effective depth of the sediments (20 cm) was modelled using a quadratic (second order) driving force and a corresponding mass transfer coefficient. The model coefficients were calibrated using field and laboratory data. Results of the modelling suggested that the sediments have a small effect on instream concentrations during the active phases of mining and milling. The sediments were predicted to accumulate sufficient adsorbed mass, during the operational phase of mining and milling, to act as a distributed instream source after completion of milling activities. The significance of this post-operational source was a function of the initial effluent loading, elapsed time and site specific river characteristics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Microbial metabolism in surface sediments and its role in the immobilization of phosphorus in oligotrophic lake sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 261-268 
    Details
    ISSN: 1573-5117
    Keywords: microbial metabolism ; phosphorus ; sediments ; oligotrophic lake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Rapid microbial metabolism and a large phosphorus uptake potential were observed in surface sediments of Lake George, New York. This sediment (termed the flocculent layer) also exhibited a phosphorus limited condition and a large reservoir of inorganic phosphorus associated with humic substances. These observations suggest that the empirically observed phosphorus retention in oligotrophic lake sediments may be promoted by a rapid cycling of phosphorus between microflora and its associated organic matter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940117
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Distribution and concentrations of naturally-occurring radionuclides in sediments in a uranium mining area of northern Saskatchewan, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 355-361 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; uranium ; radium ; radionuclides ; models
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Uranium mining and milling operations can contribute to environmental degradation through the increased release of naturally-occurring radionuclides. However, studies of the interactions of these radionuclides with freshwater sediments have been limited. The present study examined the vertical distribution of uranium, thorium, radium-226, polonium-210 and lead-210 in undisturbed sediment cores collected in the vicinity of mining, milling and exploration activities. Uranium levels in surface sediments ranged from 1.9 to 5650 µg g−1, Ra-226 from 〈0.1 to 480 pCi g−1 and Pb-210 from 0.8 to 931 pCi g−1 in the samples reported here, with the highest values occurring downstream of waste rock disposal areas. Concentrations usually decreased with depth, and there was little evidence of any strong effect of bioturbation on radionuclide profiles at the scale examined here. Mathematical models of uranium and radium-226 adsorption on and movement into the sediment were constructed, based on expected adsorption coefficients and estimated loading. The model predictions of radionuclide distribution with depth were qualitatively similar to those actually measured, but the predicted concentrations were generally lower than those observed, both in unaffected areas and in areas adjacent to uranium extraction activities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940125
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Distribution and concentrations of naturally-occurring radionuclides in sediments in a uranium mining area of northern Saskatchewan, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 355-361 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; uranium ; radium ; radionuclides ; models
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Uranium mining and milling operations can contribute to environmental degradation through the increased release of naturally-occurring radionuclides. However, studies of the interactions of these radionuclides with freshwater sediments have been limited. The present study examined the vertical distribution of uranium, thorium, radium-226, polonium-210 and lead-210 in undisturbed sediment cores collected in the vicinity of mining, milling and exploration activities. Uranium levels in surface sediments ranged from 1.9 to 5650 µg g−1, Ra-226 from 〈0.1 to 480 pCi g−1 and Pb-210 from 0.8 to 931 pCi g−1 in the samples reported here, with the highest values occurring downstream of waste rock disposal areas. Concentrations usually decreased with depth, and there was little evidence of any strong effect of bioturbation on radionuclide profiles at the scale examined here. Mathematical models of uranium and radium-226 adsorption on and movement into the sediment were constructed, based on expected adsorption coefficients and estimated loading. The model predictions of radionuclide distribution with depth were qualitatively similar to those actually measured, but the predicted concentrations were generally lower than those observed, both in unaffected areas and in areas adjacent to uranium extraction activities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391951
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    The fractionation of iron-phosphorus compounds in sediments studied by Mössbauer spectroscopy (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 697-700 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; Mössbauer spectroscopy ; iron ; phosphorus ; geochemistry ; analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Iron compounds of phosphorus form a large part of the phosphorus bound in sediments. Mössbauer spectroscopy is a technique that enables us to study, directly, chemical forms of iron in solid samples. Mössbauer spectroscopy allowed us to check, directly, the selectivity of the extraction scheme for soil phosphorus proposed by Chang & Jackson (1957), but only as far as the iron compounds are concerned. It appears that selectivity of the extraction method leaves much to be desired.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391985
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Spatial heterogeneity in whole lake sediments — towards a loading estimate (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 235-240 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; nutrients ; loading estimates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Studies of nutrient loadings, to shallow culturally eutrophied Alberta lakes, suggest internal inputs are significant. In this regard, estimation of bottom sediment P loads to Lake Wabamun (80 km2, 5.5 m $$\bar x$$ depth) were examined. Initially we determined the spatial variability in Total Organic Content (% loss on ignition) and Total Phosphorus, as indicators. Phosphorus fractions and biologically available phosphorus (BAP) were measured at specific stations. These data showed a very uniform distribution in sediment type with a Total Organic Content of 40.6 ± 3.3 (95% C.L.) at the west end, gradually declining to 26.3 ± 0.9 at the east end. Transects performed at routine monitoring stations indicate the representativeness of each station, e.g., station 2, 40.8 ± 1.3 (10 sites). One explanation of this uniformity is provided from210Pb analysis of shallow cores which indicate mixing to a depth of 16 cm. This is also thought to explain the mechanics of P loading to the water phase. Finally, Total Organic Content relates well to BAP (r2 = 0.80). It is hoped that this simple technique may well permit more precise extrapolation to whole lake BAP estimates at least on this lake.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391940
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    An investigation into some physical and biotic effects of flooding on reservoir mud previously subjected to a period of aerial exposure (1982)
    Springer
    Hydrobiologia 97 (1982), S. 27-35 
    Details
    ISSN: 1573-5117
    Keywords: Hong Kong ; man-made lake ; marginal zone ; sediments ; Melanoides tuberculata ; freshwater gastropods ; allochthonous ; water-level fluctuations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A series of laboratory experiments were carried out in order to investigate the effects of selected physical and biotic processes on the substratum of a recently flooded gently sloping marginal zone of Plover Cove Reservoir, Hong Kong. The physical effects of disturbance of the sediments promoted the redistribution of organic matter, as shown by differences in the percentage of organic matter in the supernatant and residue resulting when reservoir mud was stirred. It is suggested that such a process would promote the transfer of allochthonous organic carbon from the marginal zone (the area of input of such material) to the rest of the water body. Substrate characteristics were also influenced by the activities of two species of benthic gastropod,Sinotaia quadrata andMelanoides tuberculata. These animals increased the rate of production of particles from soaked blocks of parent mud when compared with experimental treatments in the absence of snails. Additionally both species enhanced the production of aggregates from fine sediments with a particle size of less than 125 µm. The magnitudes of both processes were statistically significant. Laboratory observations showed thatM. tuberculata had a significantly faster rate of aggregate and fine particulate production thanS. quadrata and it is possible that the former species may have the capacity to modify the substrate characteristics of the newly flooded marginal zone of Plover Cove.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00014957
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Effect of artificial destratification on iron, manganese, and zinc in the water, sediments, and two species of benthic macroinvertebrates in an Oklahoma lake (1982)
    Springer
    Hydrobiologia 87 (1982), S. 11-16 
    Details
    ISSN: 1573-5117
    Keywords: lake stratification ; artificial destratification ; lake mixing ; heavy metals ; sediments ; benthic macroinvertebrates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Ham's Lake was destratified in the summers of 1977 and 1978 by pumping surface water to the bottom. However, an arm was prevented from mixing by a submerged dam of a former farm pond and remained stratified. The concentration of manganese in the water increased to over 5 000 µg 1−1 in the hypolimnion of the anoxic arm in summer. Soluble manganese averaged 28% of total concentration. Total iron concentrations were relatively high in the water and sorbed iron values were extremely low in the sediments. Soluble iron averaged 12% of total concentration. Zinc values were low in the water and sediments. Chaoborus punctipennis and Chironomus riparius concentrated iron and zinc and discriminated against manganese. Concentration factors were unaffected by mixing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00016657
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    The fractionation of iron-phosphorus compounds in sediments studied by Mössbauer spectroscopy (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 697-700 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; Mössbauer spectroscopy ; iron ; phosphorus ; geochemistry ; analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Iron compounds of phosphorus form a large part of the phosphorus bound in sediments. Mössbauer spectroscopy is a technique that enables us to study, directly, chemical forms of iron in solid samples. Mössbauer spectroscopy allowed us to check, directly, the selectivity of the extraction scheme for soil phosphorus proposed by Chang & Jackson (1957), but only as far as the iron compounds are concerned. It appears that selectivity of the extraction method leaves much to be desired.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000069
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Deepwater sediments and trophic conditions in Florida lakes (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 597-602 
    Details
    ISSN: 1573-5117
    Keywords: eutrophication ; diagenesis ; sediments ; nitrogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediment cores were taken from near maximum depth in 15 Florida lakes representing a wide range of trophic conditions. Chemical analyses of surface sediments showed Al, Fe, and Ca to be the most abundant elements in all samples, and the ratio of Al to Ca to be smaller for eutrophic lakes. Sediment organic matter increased with trophic state, as did the degree to which it was enriched in nitrogen. Corresponding sediment C/N ratios decreased with increasing lake trophic state and showed significant negative correlation with chlorophylla, total N, and total P in the water column. Concentrations of sedimentary chlorophyll derivatives showed some relation to trophic state but differences in basin morphometry hinder its use as an inter-lake index of chlorophyll production.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940148
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Introduction (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 1-8 
    Details
    ISSN: 1573-5117
    Keywords: symposium ; sediments ; freshwater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391917
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Comparison of sediment energy-texture relationships in marine and lacustrine environments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 71-84 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; lakes ; seas ; oceans ; energy relationships ; population statistics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Sediments in the marine environment are generally subject to higher energy levels than those of lake systems, and lakes are virtually unaffected by tidal range which modifies beach structures formed in response to wave effects. However, despite different energy levels, the textural characteristics of both marine and lacustrine sediments are very similar. The main difference between marine and lacustrine facies is the depth range over which these characteristics remain consistent. In lakes, depth limitation may influence the development of surface waves and restrict textural distributions. Simple textural relationships can be used to describe comparable marine and lacustrine sedimentary conditions. Sediments which have been altered by post-depositional erosion, such as lag deposits, or by ice-drop or wind blown settlement, show comparable textural modifications. The settlement of silt and clay size particulates, in the marine environment and lakes, may differ slightly because of the chemical differences between salt and fresh water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391923
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Whole-lake lead burdens in sediments of lakes in southern Ontario, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 121-130 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; lead
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The anthropogenic stable lead content of the sediments of eight softwater Precambrian lakes in southern Ontario was measured at 34–92 sites per lake. Whole-lake anthropogenic lead burdens varied between only 610 and 770 mg m−2. There was no relationship between lead burden and either water replenishment time of the lake (TW) or the ratio of watershed area to lake area (Ad/A0), which varied by factors of 4 and 12 respectively. These results can be explained if a) the lead deposition in this region is uniform, and b) the only significant input of lead to the lakes is via deposition from the atmosphere directly on the lakes' surfaces. Therefore spatial differences in anthropogenic lead within a lake represent the redistribution or focusing pattern of the sediments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391927
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Particle size distribution and chemical parameters of the sediments of a shallow turbid impoundment (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 341-353 
    Details
    ISSN: 1573-5117
    Keywords: Impoundment ; sediments ; particle size ; major ions ; nutrients ; cation exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract As part of an ecosystem study of a small mesotrophic turbid impoundment in the semi-arid part of South Africa, an investigation was made of the particle size distribution, organic content and inorganic chemical composition of the sediment. Nine transects 50 m apart were made during February 1980. Sediments were sampled with an Eckman grab. The following analyses were made: size fractionation by wet sieving, cation exchange capacity, exchangeable Na, K, Ca, Mg and PO4, total P, and loss on ignition. From the results it was clear that the finer particles, in or near the original river bed, had higher cation exchange capacity, total P, exchangeable phosphorus and organic content. Littoral areas with avian habitat and extensive macrophyte vegetation, contained coarser sediments. Organic detritus apparently migrated to the deeper part of the impoundment. Sediments of lacustrine and fluvial origin were identified by means of the Passega classification.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391950
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Lake sediments as recorders of geomagnetic field variations — applications to dating post-Glacial sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 587-596 
    Details
    ISSN: 1573-5117
    Keywords: dating ; sediments ; geomagnetic variations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Field and laboratory methods, developed to recover the record of past secular variations of geomagnetic declination and inclination carried by the remanent magnetization of some lake sediments, are described. Type curves, delineating these parameters through post-Glacial time, have now been constructed for Europe and east-central N. America. These curves, once established for any region, are useful for dating lake sediments from that region. The principal inclination features exhibited by the European curves can also be identified along the N. American curves with a delay of some 600 years, on average.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000057
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Stratigraphic and dynamic effects of sediment reworking by Great Lakes zoobenthos (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 611-622 
    Details
    ISSN: 1573-5117
    Keywords: zoobenthos ; Great Lakes ; sediments ; radionuclides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Recent sediments of the North American Great Lakes are inhabited by numerous species of macrobenthos which alter the physical and chemical properties of sediments and modify interface transport characteristics. Distributions of such radionuclides as cesium-137, lead-210, and isotopes of plutonium exhibit a zone of constant activity extending down from the sediment-water interface from 1 to 15 cm. Recent studies have confirmed that radiometrically determined mixed depths are consistent with the vertical distribution of oligochaete worms and the amphipod, Pontoporeia hoyi. Generally, 90% of the benthos are contained within the radiometrically defined mixed zone. Where comparisons are possible, rates of sediment reworking by ‘conveyor belt’ species are comparable to or exceed sedimentation rates. Systematic variations in the mixed depth occur within depositional basins with greatest depths tending to be associated with least consolidated, organically rich materials. A quantitative steady-state mixing model accounts satisfactorily for observed radioactivity and heavy metal profiles. Bioturbation appears to be an important process, limiting the resolution with which historical records of particle-associated contaminants may be reconstructed from sediment cores. As bioturbation serves to maintain contact of contaminated sediments with overlying water, this time may also characterize the long-term lake recovery for contaminants removed by burial. As the time varies with location, a mean for an entire lake is not well known, but is on the order of 20 years for Lake Huron.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000060
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Standardization of methods of analysis for heavy metals in sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 689-695 
    Details
    ISSN: 1573-5117
    Keywords: standardization ; heavy metals ; sediments ; base-line levels ; chemical partition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In studies of heavy metals in sediments, there is a need for standardization of the procedures for sample collection and preservation, chemical analyses and presentation of results. The method and depth of sampling depend on the aim of the investigation and on local sediment conditions, such as consistency of the sediment, rate of sedimentation, diagnetic processes and bioturbation. Therefore no general recommendations can be given in this respect. During collection and preservation, contamination and loss of constituents ust be avoided. In sediments, the best means for estimating total contents of metals is digestion with HF, in combination with strong acids. Other methods include X-ray fluorescence and neutron activation analyses. The use of HF is considered objectionable by some laboratories. A reasonable alternative is aqua regia. Because variations in granular composition affect metal contents, it is advisable to use the fraction 〈 63 μm for the analysis. Chemical partition of sediments provides an insight into the source of metallic constituents, and their pathways to deposition areas. A three-step extraction procedure, in the sequence 0.1 M hydroxylamine-HCl, H2O2 30% and HF, is proposed. Finally, attention is paid to the anthropogenic enrichment of metals in sediments. The establishment of base-line levels is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00000068
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Whole-lake lead burdens in sediments of lakes in southern Ontario, Canada (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 121-130 
    Details
    ISSN: 1573-5117
    Keywords: sediments ; lead
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The anthropogenic stable lead content of the sediments of eight softwater Precambrian lakes in southern Ontario was measured at 34–92 sites per lake. Whole-lake anthropogenic lead burdens varied between only 610 and 770 mg m−2. There was no relationship between lead burden and either water replenishment time of the lake (TW) or the ratio of watershed area to lake area (Ad/A0), which varied by factors of 4 and 12 respectively. These results can be explained if a) the lead deposition in this region is uniform, and b) the only significant input of lead to the lakes is via deposition from the atmosphere directly on the lakes' surfaces. Therefore spatial differences in anthropogenic lead within a lake represent the redistribution or focusing pattern of the sediments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Zinc in water and sediments of two finnish lakes (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 155-160 
    Details
    ISSN: 1573-5117
    Keywords: heavy metals ; zinc ; lakes ; sediments ; pollution ; industrial load ; sedimentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The distribution of zinc in Lake Vanajavesi and Lake Mallasvesi, South Finland, was determined on the basis of water and sediment studies. Lake Vanajavesi is one of the most polluted of large inland lakes, in Finland. The zinc load comes mainly from industrial sources. Lake Mallasvesi, situated near Vanajavesi, is in almost natural condition. The water samples were taken by a Ruttner sampler. In collecting sediment samples, a freezing technique was used. The results of zinc analyses indicate that, during several winters, zinc has spread with waste water to different parts of L. Vanaja against the main course of flow. A close correlation between sedimentation of zinc and waste discharge from a textile factory was found in the present study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Model for instream regulation of radioisotopes and heavy metals in riverine waters subjected to a uranium mill discharge (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 175-188 
    Details
    ISSN: 1573-5117
    Keywords: simulation ; sediments ; radioisotopes ; heavy metals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the Athabaska sandstone region of northern Saskatchewan, mining and milling of uranium-bearing ore is subjecting, and will continue to subject, surface waters to inputs of soluble heavy metals and uranium and thorium decay series radioisotopes. A mathematical simulation model was developed to assess the role of riverine sediments in regulating soluble concentrations of heavy metals and radioisotopes released to the environment through treated mining and milling process effluents. Specific elements studied included As, Ni, Pb, U, and Ra-226. The model considered that diffusion into sediment porewater and adsorption by sediment particulates from sediment porewater were the two dominant mechanisms regulating sediment loading. Experiments indicated that the equilibrium adsorption behaviour of the heavy metals and radioisotopes studied could be adequately explained using a linear adsorption isotherm, over the range of concentrations expected in the environment. Experimentally determined linear isotherm slopes ranged from 200 ml g−1 to 21 000 ml gl. Diffusion into the effective depth of the sediments (20 cm) was modelled using a quadratic (second order) driving force and a corresponding mass transfer coefficient. The model coefficients were calibrated using field and laboratory data. Results of the modelling suggested that the sediments have a small effect on instream concentrations during the active phases of mining and milling. The sediments were predicted to accumulate sufficient adsorbed mass, during the operational phase of mining and milling, to act as a distributed instream source after completion of milling activities. The significance of this post-operational source was a function of the initial effluent loading, elapsed time and site specific river characteristics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02391934
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Transport of iron and manganese in relation to the shapes of their concentration-depth profiles (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 463-471 
    Details
    ISSN: 1573-5117
    Keywords: iron ; manganese ; sediments ; water ; transport ; model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A model is presented which describes the transport of iron and manganese in the vicinity of a redox boundary. It is based on input of a particulate component, to form a point source, from which soluble species diffuse along a concentration gradient. The shapes of concentration-depth profiles in marine and freshwater sediments and water columns are reviewed and discussed in terms of the model. Transport, either entirely within a water column or within the sediment, may be simply treated because the rate of vertical transport can be regarded as constant. The discontinuity in the rate of vertical transport which occurs at the sediment-water interface can provide a complicated example of the model, especially when it coincides with the redox boundary. Authigenic mineral formation processes can modify the model, sometimes to such an extent that it becomes invalid. This is particularly true for soluble iron profiles in organically rich marine sediments. Sampling interval is critical to the resultant profile shape and must be relevant to the particular environment, e.g. metres in water columns and millimetres in sediments. The differences in the rates of reduction and oxidation of iron and manganese tend to modify both the position of the profile with respect to the redox-cline and its stage of development in a seasonally anoxic system. It is these factors which determine why most of the iron which reaches a sediment is permanently incorporated whereas manganese is re-released. This mechanism determines the average ratio of iron to manganese in sedimentary rocks. The development of peaked profile shapes in water columns implies that under certain conditions dissolved iron and manganese may be transported from the water column to the pore waters of the sediment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940134
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Lake sediments as recorders of geomagnetic field variations — applications to dating post-Glacial sediments (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 587-596 
    Details
    ISSN: 1573-5117
    Keywords: dating ; sediments ; geomagnetic variations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Field and laboratory methods, developed to recover the record of past secular variations of geomagnetic declination and inclination carried by the remanent magnetization of some lake sediments, are described. Type curves, delineating these parameters through post-Glacial time, have now been constructed for Europe and east-central N. America. These curves, once established for any region, are useful for dating lake sediments from that region. The principal inclination features exhibited by the European curves can also be identified along the N. American curves with a delay of some 600 years, on average.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940147
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Stratigraphic and dynamic effects of sediment reworking by Great Lakes zoobenthos (1982)
    Springer
    Hydrobiologia 91-92 (1982), S. 611-622 
    Details
    ISSN: 1573-5117
    Keywords: zoobenthos ; Great Lakes ; sediments ; radionuclides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Recent sediments of the North American Great Lakes are inhabited by numerous species of macrobenthos which alter the physical and chemical properties of sediments and modify interface transport characteristics. Distributions of such radionuclides as cesium-137, lead-210, and isotopes of plutonium exhibit a zone of constant activity extending down from the sediment-water interface from 1 to 15 cm. Recent studies have confirmed that radiometrically determined mixed depths are consistent with the vertical distribution of oligochaete worms and the amphipod,Pontoporeia hoyi. Generally, 90% of the benthos are contained within the radiometrically defined mixed zone. Where comparisons are possible, rates of sediment reworking by ‘conveyor belt’ species are comparable to or exceed sedimentation rates. Systematic variations in the mixed depth occur within depositional basins with greatest depths tending to be associated with least consolidated, organically rich materials. A quantitative steady-state mixing model accounts satisfactorily for observed radioactivity and heavy metal profiles. Bioturbation appears to be an important process, limiting the resolution with which historical records of particle-associated contaminants may be reconstructed from sediment cores. As bioturbation serves to maintain contact of contaminated sediments with overlying water, this time may also characterize the long-term lake recovery for contaminants removed by burial. As the time varies with location, a mean for an entire lake is not well known, but is on the order of 20 years for Lake Huron.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00940150
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Gas chromatographic determination of total amino acids and protein in sediments using the ninhydrin-CO2 reaction (1982)
    Springer
    Hydrobiologia 97 (1982), S. 81-86 
    Details
    ISSN: 1573-5117
    Keywords: amino acids ; protein ; sediments ; ninhydrin reaction ; gas chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A sensitive modification of the ninhydrin-CO2 method involving the gas chromatographic determination of the total protein and amino acid content of sediment is described. The method gives a linear response over the amino acid concentration range 10−5 M to 4 × 10−2 M. It can be used for whole sediment, hydrolysates and interstitial water. The performance of the method is compared with the fluorescamine method for primary amines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00014961
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Pattern of follicular development during the estrous cycle of aged rats (1982)
    Springer
    Cell & tissue research 225 (1982), S. 229-234 
    Details
    ISSN: 1432-0878
    Keywords: Preovulatory follicle ; Cell division ; Age ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pattern of follicular development during the estrous cycles of aged rats was examined and compared with that of mature rats. In both, preovulatory follicles are derived from a select group of small pre-Graafian follicles which begin to develop at estrus and reach the preovulatory size by the morning of proestrus, but the rate of growth, as judged by an increase in the percentage of granulosa cells incorporating 3H-thymidine, is accelerated in the follicles of aged rats. A second mechanism, which accounts for preovulatory follicles in aged rats, involves the rescue from atresia of pre-Graafian and preovulatory follicles. The existence of this mechanism is supported by the observation that at metestrus in aged rats virtually all follicles, regardless of their state of atresia, possess a high percentage of granulosa cells incorporating 3H-thymidine, indicating that the follicles are growing rapidly. However, some of these rapidly growing follicles show signs of atresia such as pyknotic nuclei within their granulosa cell layers. Since follicles in the initial stage of atresia contain defective oocytes (Peluso et al. 1979b), their rescue and development into preovulatory follicles would result in the ovulation of defective oocytes, a fact which accounts in part of the lower fertility in these older animals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216232
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Immunoreactive material resembling vertebrate neuropeptides in the corpus cardiacum and corpus allatum of the insect Leucophaea moderae (1982)
    Springer
    Cell & tissue research 225 (1982), S. 319-329 
    Details
    ISSN: 1432-0878
    Keywords: Vertebrate-type neuropeptides ; Neuroendocrine system of insects ; Neurosecretion ; Peptidergic neurons ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence and differential distribution of substances antigenically related to known vertebrate neuropeptides demonstrated within the corpus cardiacum of the insect Leucophaea are as follows: Of ten mammalian antisera tested, six yielded substantial immunoreactive deposits resembling oxytocin, somatostatin, Substance P, met-enkephalin, bombesin, and neurotensin, respectively. In the remaining four, the reaction was moderate (vasopressin, β-endorphin) or marginal (LH-RF, calcitonin). With regard to their regional distribution, these biochemically distinct reaction products seem to fall into two groups: (1) Materials resembling oxytocin, vasopressin, met-enkephalin, β-endorphin (and presumably also neurotensin and LH-RF) predominate in the central release area of the organ and are considered to be of extrinsic (cerebral) origin. (2) Substances localized primarily in areas rich in intrinsic glandular cells of the corpus cardiacum, and revealed by antisera raised against somatostatin, Substance P, and bombesin, are judged to be synthesized and stored within this organ. In peptidergic fibers entering the adjacent corpora allata, thus far Substance P-, β-endorphin-, and LH-RF-like immunoreactivities have been demonstrated. Some of these “new” neuropeptides may be contained in classical neurosecretory neurons, formerly identified by less specific methods, others must be assigned to additional peptidergic neurons heretofore unknown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214685
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Immunocytochemical demonstration of peptidergic cells in the pond snail Lymnaea stagnalis with an antiserum to the molluscan cardioactive tetrapeptide FMRF-amide (1982)
    Springer
    Cell & tissue research 225 (1982), S. 347-354 
    Details
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Cardioactive peptide ; Lymnaea stagnalis ; Neurohormone ; Neurotransmitter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary With an antiserum to the molluscan cardioactive tetrapeptide FMRF-amide immunoreactive perikarya and nerve fibers were identified in the central and peripheral nervous system of the pond snail Lymnaea stagnalis. Their localization is described. The same antiserum yielded reactive product in particular cells of the epithelium of the alimentary tract. The use of two different fixatives, glutaraldehyde, and a mixture of glutaraldehyde, picric acid, and acetic acid (GPA) showed that certain nerve cells can be identified only in material fixed with either the one or the other of these two fixatives, a result which indicates that in Lymnaea more than one FMRF-amide-like substance may occur. “Positive” axon endings were found in the periphery of various nerves, i.e., in places where neurohormones are released into the blood. Other fibers were found to end, probably synaptically, on other neurons, on epithelial cells in the stomach, and between muscle cells in various parts of the body, e.g., in the heart. In these cases the FMRF-amide-like substance may function as a neurotransmitter or a neuromodulator.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214687
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Morphological studies on neuroglia (1982)
    Springer
    Cell & tissue research 225 (1982), S. 469-485 
    Details
    ISSN: 1432-0878
    Keywords: Microglial cells ; Postnatal development ; Enzyme histochemistry ; NDPase, TPPase ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The postnatal development of microglial cells was investigated in the neonatal rat brain by use of light- and electron microscopy, including enzyme-histochemical techniques. Microglial cells were selectively stained by demonstration of their nucleoside diphosphatase (NDPase) activity and classified into three types: 1) In the early postnatal period, “primitive microglial cells” showing scantily ramified processes were found in the cerebral cortex, the hippocampal formation, and the hypothalamus. During the course of the first postnatal week the processes of this cell type developed gradually and the cells were transformed into typical ramified microglial cells, called “resting microglial cells”. 2) “Amoeboid microglial cells” showing typical features of macrophages were characteristic of the cerebral white matter. 3) “Round microglial cells” possessing a round soma and few pseudopodia but no characteristic processes occurred in large numbers in the sub ventricular zone of the lateral ventricle and as single elements in the vicinity of blood vessels. Histochemically, thiamine pyrophosphatase (TPPase) was demonstrated only in the fully developed, ramified microglial cells (“resting microglial cells”), which could be readily observed in the central nervous tissue from the age of 14 day. “Round and amoeboid microglial cells” did not show TPPase activity and disappeared after 14 days of postnatal life. By use of electron microscopy, in neonatal rats NDPase activity was apparent in the plasma membrane of the three types of microglial cells (“primitive, round, and amoeboid” types). They showed basically similar submicroscopic characteristics, i.e., well-developed Golgi apparatus, long strands of roughsurfaced endoplasmic reticulum, single dense bodies and vacuoles, and numerous ribosomes. “Amoeboid microglial cells” were characterized by their well-developed cytoplasmic vacuoles and phagocytic inclusion bodies. The present study strongly suggests a mesodermal origin for these microglial elements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214798
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Immunoreactive material resembling ovine prolactin in perikarya and nerve terminals of the rat hypothalamus (1982)
    Springer
    Cell & tissue research 226 (1982), S. 121-131 
    Details
    ISSN: 1432-0878
    Keywords: Rat brain ; Hypothalamus ; Prolactin ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence of prolactin (PRL)-like material is demonstrated in the brain of rats with the aid of anti-ovine PRL (oPRL) IgG as primary antibody in the unlabeled antibody-enzyme method. Immunoreactive deposits are visualized as an intraneuronal constituent with a widespread distribution in the hypothalamus and neural lobe of the pituitary. Dense networks of reactive nerve terminals derived from two prominent fibre tracts, a ventral (VHT) and a dorsal hypothalamo-neurohypophysial tract (DHT) are seen. The VHT is confined to the median eminence and pars oralis tuberis, the DHT to the pars caudalis tuberis. Both fibre tracts pass through the infundibular stalk into the neural lobe. The origin of the immunoreactive nerve terminals can be elucidated only to some extent. The VHT gives off beaded fibres entering the ependymal and glandular layer of the median eminence. Immunoreactive perikarya are observed in the supraoptic nucleus, the paraventricular nucleus, the anterior hypothalamic nucleus, the anterior commissural nucleus, the preoptic nucleus and the interstitial nucleus of the stria terminalis. A few of the immunoreactive perikarya are observed in close connection with brain vessels and the ependymal cells of the third ventricle. The results indicate that the anti-oPRL has a unique region specificity implying that only a segment of the mammalian PRL molecule is present in these nuclei of the brain. Fragments of PRL may function as neuromodulators or neurotransmitters in the rat brain.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217087
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Immunocytochemistry of gonadotropic cells and identification of cell types in ultrathin cryosections of the pituitary of the rainbow trout, Salmo gairdneri (1982)
    Springer
    Cell & tissue research 226 (1982), S. 177-194 
    Details
    ISSN: 1432-0878
    Keywords: Cryo-ultramicrotomy ; Immunocytochemistry ; Pituitary gland ; Gonadotropic cells ; Salmo gairdneri
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The most frequently occurring cell types in the pars distalis of the pituitary gland of the rainbow trout, (i) the lactotropic, (ii) the gonadotropic, and (iii) the somatotropic cells, were identified in cryosections. Their morphological characteristics were compared with those of Epon-embedded material. Cell location, cell form, position of the nucleus, arrangement of rough endoplasmic reticulum and sizes of secretory granules proved to be useful parameters for identification. The size distribution of secretory granules of corresponding cells in cryosections and Epon sections proved to be similar. Additionally, both the immunoferritin and the unlabeled antibody enzyme method were applied for the immunocytochemical labeling of gonadotropic hormone-producing cells in cryosections. Anti-salmon-GTH as well as anti-carp-GTH serum showed the presence of GTH in both the smaller and the larger granules of the classical GTH cells, but also produced a reaction in TSH cells. Labelling of TSH cells was absent when using anti-β-carp-GTH. Specificity of the reaction depended upon the degree of dilution of the anti-GTH serum. Results with dilutions of 1∶4,000 and 1∶8,000 in the unlabeled antibody enzyme method, and of 1∶8,000 up to 1∶32,000 in the immunoferritin technique were optimal. Acid phosphatase activity in the smaller granules was demonstrated by enzyme cytochemistry in Epon sections. The relationship of the presence of hormone in these granules is discussed. The high sensitivity of the immunocytochemical labeling procedure is discussed with respect to cryo-ultramicrotomy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217092
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Analysis of trimethylsilyl-isopropylidene derivatives of sorbose by combined gas chromatography- and mass-spectrometry (1982)
    Springer
    Chromatographia 15 (1982), S. 704-706 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Isopropyliden-sorboses ; TMS-derivatives ; GC-MS combined technique ; Mass spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A method has been developed using gas chromatography — electron impact mass spectrometry for the determination of the di-0-isopropylidene-sorbofuranose and mono-0-isopropylidene-sorbofuranose. The compounds are separated as their trimethylsilyl derivatives on a capillary column coated with the stationary phase SE-52. The mass spectra show that the silylation reaction is quantitiative and that the isopropylidene groups does not change.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261889
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Gas chromatographic analysis of ethylbenzene hydroperoxide (1982)
    Springer
    Chromatographia 15 (1982), S. 183-185 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Analysis of ethylbenzene hydroperoxide ; Time normalization method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A gas chromatographic method, based on the time normalization technique, is described for the analysis of ethylbenzene hydroperoxide in mixtures containing ethylbenzene, acetophenone, 1-phenylethanol, benzaldehyde and phenol. Different liquid phases were tested and the best results were obtained with tricresyl phosphate and neopentyl glycol sebacate. The influence of the support, the liquid loading and the gas velocity are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261537
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Retention index values of hydrocarbons on open-tubular columns coated with methylsilicone liquid phases (1982)
    Springer
    Chromatographia 15 (1982), S. 625-630 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Open-tubular (capillary) columns ; Comparison of liquid phases ; Influence of temperature ; Retention index data
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The influence of temperature and liquid phase film thickness of open-tubular (capillary) columns on the retention index values of hydrocarbons on methylsilicone liquid phases is discussed. Data obtained on methylsilicones and squalane are compared. Retention index values of 43 hydrocarbons between 40 and 70 °C on OV-101 liquid phase are listed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02279488
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Kinetic study of the drying step of supported catalysts by reversed-flow gas chromatography (1982)
    Springer
    Chromatographia 15 (1982), S. 351-354 
    Details
    ISSN: 1612-1112
    Keywords: Supported catalysts ; Reserved-flow GC ; Drying step ; Gas chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Application of reversed-flow gas chromatography to study the drying step in the preparation of supported catalysts is proposed. It is demonstrated that this technique can be applied to investigate the kinetic law followed, as well as to obtain kinetic parameters of drying (rate constants, activation energies and frequency factors). Amaterial illustrating this application is γ-Al2O3 impregnated with usual organic solvents (n-C5H12,n-C6H14,n-C7H16, CH3COCH3 and CH3CH2OH). It was found that in all cases above a simple first-order law based onone kind of active site is followed. Moreover, it was observed that the activation energyE a of the drying process increases almost linearly with the relative molecular mass of the solvent, whereas for the same solventE a increases with the amount used. The operation of a kinetic compensation effect suggests “similar” activated complexes of the various solvents used.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02259216
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Characterization, evaluation and in-situ cross-linking of new polar phases in capillary gas chromatography (1982)
    Springer
    Chromatographia 16 (1982), S. 63-68 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Fused silica capillaries ; New polar phases: OV-1701 and RSL-310 ; Immobilization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The possibilities of OV-1701 and RSL-310, two new stationary phases, have been evaluated for capillary gas chromatography in fused silica columns. OV-1701 is a cyanopropylphenyldimethyl polysiloxane of moderate polarity possessing excellent chromatographic characteristics. The phase exhibits high coating and chromatographic efficiencies, high temperature stability and is suitable for cross-linking. RSL-310 is a polar liquid stationary phase yet to be permanently bonded in a capillary column. The selectivity of both phases extends the applicability of fused silica columns.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258871
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Gas-liquid chromatography of isopropylidene monosaccharides and their trimethylsilyl derivatives (1982)
    Springer
    Chromatographia 15 (1982), S. 241-244 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Monosaccharides ; Polyols ; GC of TMS derivatives
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary This paper describes the gas chromatographic separation of the mixture of isopropylidene monosaccharides, and their trimethylsilyl derivatives. Based on the total analysis time and resolution the best stationary phase was SF-96 using Chromosorb G as the solid support and temperature programming.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02265655
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    A new device for contamination-free injection for gas chromatographic trace estimation of oxygen and nitrogen (1982)
    Springer
    Chromatographia 15 (1982), S. 312-314 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Injection-port modification ; Oxygen and nitrogen traces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The paper presents a new device modifying normal injection port of a gas chromatograph for eliminating air contamination thus enabling determination of traces of oxygen or nitrogen. Further modification is also proposed which enables the analysis to be carried out with a limited quantity of sample gas. Potential application of this device in the analysis of reactive gases like florine has been indicated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02265684
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Occurrence and prevention of isomerization of ligustilide during gas-liquid chromatography on packed columns (1982)
    Springer
    Chromatographia 15 (1982), S. 358-360 
    Details
    ISSN: 1612-1112
    Keywords: Phthalides ; Gas chromatography ; Chromosorb W ; Isomerization ; Ligustilide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary During GLC of naturally occurring mixtures of phthalides on packed columns an artefact was sometimes detected that originated from Z-ligustilide. Active sites of Chromosorb W were responsible for the formation of the artefact, that was assumed to be E-ligustilide as GC-MS revealed that its mass spectrum was identical with that of Z-ligustilide. No isomerization was observed when freshly coated Chromosorb W was used or the support was deactivated by benzoyl chloride or melamine. The identity of the artefact was confirmed by UV irradiation experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02259218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Gas chromatographic determination of arsenic in low concentrations in inorganic materials (1982)
    Springer
    Chromatographia 15 (1982), S. 30-32 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Arsenic ; Inorganic materials
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A method is described for the quantitative chlorination and extraction of arsenic as arsenic trichloride from a number of alloys. The conditions for the quantitative gas chromatographic measurement of the volatile chloride have been studied. The proposed method for inorganic materials is very fast giving results within 10 min; sensitive, 1.5·10−13 g As can be detected, simple and accurate. At the ng level of As the error is about 20% with a standard deviation less than 20%, and at the 10pg level the error is about 36% with a standard deviation of 44%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02269036
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Multiple preparative chromatography (1982)
    Springer
    Chromatographia 15 (1982), S. 765-768 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Preparative scale chromatography ; Capacity ; Dual-stage separation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The capacity of different versions of single- and dual-stage separation of mixtures on a preparative scale is considered. It has been shown that dual-stage separation with intermediate condensation considerably enhances the capacity of the installation as compared with a single-stage process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261373
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    High efficiency microbore GC columns using porous bead supports (1982)
    Springer
    Chromatographia 15 (1982), S. 117-124 
    Details
    ISSN: 1612-1112
    Keywords: Various packed GC column ; Gas chromatography ; Porous layer beads ; GC/MS analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Theoretical comparisons of various packed GC column types are presented with respect to analysis time, efficiency, sample dilution, and sample capacity for a given maximum inlet pressure. In particular, totally porous particles, porous layer beads, and glass beads are compared with one another. It is shown that 30 μm porous layer beads offer a useful compromise between analysis time and plate count with relatively good sample capacity. Moreover, when using 1 mm i.d. columns (microbore), outlet flow rates that are reasonable for direct coupling to magnetic sector mass spectrometers are achieved making these columns suitable for GC/MS. Using 30 μm Zipax porous layer beads, columns yielding 8,000 to 10,000 plates/meter have been produced with inlet pressures of 13 to 26 atm. A simple modification of the injection port converts the maximum inlet pressure of a commercial gas chromatograph to 26 atm. With such pressures, columns in excess of 20,000 plates can be achieved. Chromatograms are presented illustrating the promise of these microbore columns for GC and GC/MS analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290444
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    A chromatoscopic study of fluorene, indenes and styrene (1982)
    Springer
    Chromatographia 15 (1982), S. 245-248 
    Details
    ISSN: 1612-1112
    Keywords: Chromatoscopy ; Gas chromatography ; Graphitized carbon black ; Molecular structure and retention ; Aromatic hydrocarbons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A molecular-statistical calculation of the retention volumes at zero sample size on graphitized thermal carbon black is carried out for quasi-rigid molecules of fluorene, indene, 1-methylindene, 2-methylindene and three dimethylindenes. A reasonable agreement is observed between the calculated and the available experimental gas chromatographic data. The potential barrier to internal rotation and the torsional angle in styrene molecules are estimated by comparing theoretically calculated and measured retention volumes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02265656
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Gas chromatography in qualitative analyses. An investigation of the oxidation of some silicones used as gas chromatographic stationary phases (1982)
    Springer
    Chromatographia 15 (1982), S. 355-357 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Silicone liquid phases ; Oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The on-column oxidation of apolar and polar silicones used as gas chromatographic stationary phases is investigated. Even at 225° the effects of oxidation are found to be slight. Of the materials investigated the methylphenylsilicones are the most stable.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02259217
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Glass capillary gas chromatography of chlorinated methyl acetates, propanoates and butanoates on Carbowax 20M and SE-30 columns (1982)
    Springer
    Chromatographia 15 (1982), S. 505-508 
    Details
    ISSN: 1612-1112
    Keywords: Glass capillary ; Gas chromatography ; Methyl chloroacetates ; Methyl chloropropanoates ; Methyl chlorobutanoates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The gas chromatography of all chlorinated methyl acetates, methyl propanoates and methyl mono- and dichlorobutanoates has been studied on Carbowax 20M and SE-30 glass capillary columns under various running conditions. The order of elution on a non-polar column was largely determined by the boiling point of esters, whereas on a polar column it was much influenced by the structure of compounds. Complete separation of the combined mixture of all 27 compounds could not be achieved, however, methyl 3,3-dichlorobutanoate was the only ester overlapped on both columns in spite of the various column temperatures used. The best separation of the mixture was on Carbowax 20M with a temperature program from 50°C at 8°C/min, isothermal running conditions leading either to poor separation of volatile components or long analysis time and broad peaks of higher chlorinated esters. The relative retention times for compounds at the various column temperatures are given and the retention order on a polar and on a non-polar column discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02260284
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    The structure and properties of n-octadecanol film present on the surface of a carbon-silica adsorbent (1982)
    Springer
    Chromatographia 15 (1982), S. 517-520 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Carbon-silica adsorbents ; n-Octadecanol film ; Phase transitions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The properties of the n-octadecanol film on carbon-silica adsorbent (Carbosil) were investigated. It was found that n-octadecanol forms an oriented film on the Carbosil's surface. If the surface of the basic silica gel is not completely covered with carbon, then the phase transition takes place in this film at a temperature higher than the melting temperature of n-octadecanol. One may distinguish two forms of this film, characterised by the different structures and the temperatures of the phase transitions. The first exists on the surface of silica gel unblocked by carbon. This part of the film is a monolayer, in which the alcohol molecules are vertically oriented. The solid compact-liquid expanded type phase transition at the well-defined temperature occurs in this film. In the second part of the film formed on the carbon surface, there is a multilayer of n-octadecanol. Its molecules are probably parallely oriented in relationship to the adsorbent surface. This film desintegrates progressively when the temperature increase. Maximum temperature of this phase transition is lower than the temperature of its analogue on pure silica gel surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02260287
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Quantitative capillary gas chromatographic analysis (1982)
    Springer
    Chromatographia 15 (1982), S. 546-558 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Capillary columns ; Quantitative analysis ; Sample inlet systems ; High-speed analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The attainment of precise quatitative analytical data using open-tubular (capillary) columns in standard, commercially available gas chromatographic instrumentation is demonstrated. Key elements in the design and proper utilization of the instrumentation are discussed. The function of the various sample introduction systems is elaborated and their quantitative performance demonstrated. The extra-column contribution to band-spreading is determined and the resultant data is used assessing the suitability of commercial instrumentation for highspeed capillary gas chromatography. The quantitative analysis of a sample containing some eleven components in less than thirty seconds is shown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02280373
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Crystal hydrates: an investigation of the use of crystal hydrates as stationary phases in gas chromatography (1982)
    Springer
    Chromatographia 16 (1982), S. 126-131 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Crystal hydrates as stationary phases ; Mobile Phases containing water ; Selective retentions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The use of crystallohydrates, crystallohydrate solutions and melts as stationary phases in gas chromatography has been proposed. Crystallohydrates have been shown to display high selectivity in the separation of polar organic compounds when use is made of water vapours as the mobile phase. Some aspects of gas-liquid chromatography in water vapours and with the stationary phase comprising crystallohydrates have been studied, and the preliminary results obtained point to the desirability of further progress in this field.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258882
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Phenols in whisky (1982)
    Springer
    Chromatographia 16 (1982), S. 201-203 
    Details
    ISSN: 1612-1112
    Keywords: Phenols ; Whisky ; Gas chromatography ; Aroma compounds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Twelve volatile phenols were identified in whisky by combined gas chromatography-mass spectrometry. Of these phenols 2,4-dimethylphenol was found for the first time in the aroma of whisky. The content of phenol, o-, m-, and p-cresol, guaiacol, p-ethylphenol, p-ethylguaiacol and eugenol in whiskies originating from different countries was determined by gas chromatography as their 2,4-dinitrophenyl ethers using electron capture detection. The results show that Scotch whiskies differ from others in the content of o-, m-, and p-cresol. The odour threshold values of phenols studied were determined in a 10% (v/v) ethanol-water mixture and in some cases also in the whiskies. Cresols have been found to make contribution to the aroma of Scotch whisky.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258900
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    From gas chromatography to gaia (1982)
    Springer
    Chromatographia 16 (1982), S. 26-31 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Ionization detectors ; Gaia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary This paper is an account of the development of the gaia hypothesis as seen through the eyes of a gas chromatographer. Gaia is a radical notion about the Earth which postulates the climate and chemical composition to be regulated at an optimum by and for life. Gas chromatography played an important role in the gathering of evidence for the hypothesis but most significantly the art of inventing detectors lead to the developement of a planetary life detector through which gaia was revealed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258864
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Hydrocarbon type analysis by gas chromatograph using a single capillary column and a multi-column valve system (1982)
    Springer
    Chromatographia 16 (1982), S. 282-285 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Naphtha analysis ; Gasoline analysis ; Hydrocarbon type analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Two different gas chromatographic methods are used for the determination of hydrocarbon type distribution in naphtha and gasoline samples with final boiling points up to 275 °C. The methods are based either on a single capillary column or on a valve-switched packed column system. Both methods give extensive information on paraffins, olefins, naphthenes and aromatics in total as well as by carbon-number. In each case the analysis is fully automated with a computer controlling the entire analysis from injection to results presentation. The advantages and limitations of both methods are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258920
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Trace analysis of free hydroxyacids by gas chromatography (1982)
    Springer
    Chromatographia 16 (1982), S. 322-324 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Graphitized carbon black supports ; Determination of hydroxyacids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Acid-washed graphitized carbon black (Carbopakc B) modified with trimesic adic and PEG 20M has proved to be effective for quantitative analysis of underivatized low molecular weight hydroxyacids. Calibration data revealed good linear relationships between relative peak area and concentration for lactic and 3-hydroxybutyric acids down to 0.05 mmol/l. The packing material was suitable for the analysis of aqueous solutions of hydroxyacids as it is tolerant to injections of water over a prolonged period of use. The GC system developed has been applied to the analysis of some hydroxyacids of biomedical interest in blood plasma and lactic acid contained in wine and beer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258930
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Trace determination of amines and other nitrogen containing compounds with a modiefied thermal energy analyzer (TEATM) (1982)
    Springer
    Chromatographia 16 (1982), S. 354-358 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Modified thermal energy analyzer ; Selective detection of nitrogen compounds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A modification to the TEATM Analyzer is described, which allows it to be used as a highly selective GC detector for nitrogen compounds as well as for N-nitrosamines and nitro compounds. The modified Analyzer is as sensitive as the AFID, but has a much higher selectivity towards nitrogen compounds than the AFID. Its response appears to be molar, with an output that is dependent only on the number of nitrogen atoms present. The performance of the modified Analyzer for the analysis of ammonia, amines,N-nitrosamines, nitriles and organonitro compounds is reported and discussed, as is its application to the detection of these compounds in bacon and beer samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258937
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Evaluation of the working conditions of light adsorbents and their use as sampling material for the GC analysis of organic air pollutants in work areas (1982)
    Springer
    Chromatographia 15 (1982), S. 712-716 
    Details
    ISSN: 1612-1112
    Keywords: Graphizized carbon black traps ; Organic air pollutants ; Work areas ; Gas chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The use of traps containing graphitized carbon black for the collection and pre-analysis of atmospheric pollutants in industrial areas is presented. The working conditions, in terms of trapping capability and effectiveness of release by thermal desorption are discussed. Some practical applications are also given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261891
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Influence of Van der Waals' volume of ethers, esters, carbonyls and alcohols on retention in gas chromatography stationary phases of different polyrity (1982)
    Springer
    Chromatographia 15 (1982), S. 771-775 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Van der Waals' volume ; Polarity of stationary phase ; Retention index
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Equations for Retention Index (I) versus Van der Waals, volume (Vw) on squalane are studied for alcohols, carbonyls, esters and ethers. Each equation includes linear and branching substances with different positions of the functional group in the carbon chain. The study is extended to stationary phases with polarities from 4.29 to 91.54 on the Tarjan et al. scale. Variations of the slope and origin ordinate values with the polarity of the stationary phase are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261375
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Fast analysis by gas chromatography (1982)
    Springer
    Chromatographia 15 (1982), S. 125-132 
    Details
    ISSN: 1612-1112
    Keywords: Capillary columns ; Fast analysis ; Gas chromatography ; Instrumental effects ; Optimization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The efficiency of fast GC columns depends largely on the quality of the chromatograph. A theoretical and experimental study shows the relative importance of the various phenomena involved and permits the optimization of a GC System. Extremely good performances, exceeding 2,500 plates per second have been routinely obtained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290445
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    A rapid gas chromatographic method for the analysis of acidic fermentation products (1982)
    Springer
    Chromatographia 15 (1982), S. 180-182 
    Details
    ISSN: 1612-1112
    Keywords: Acidic fermentation products ; Characterisation ; Gas chromatography ; Methyl esters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A rapid and simple method for the identification of acidic fermentation products is described. Methyl esters of volatile and non-volatile acids are separated on a single chromatographic column. Retention time data for a number of acids are tabulated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02261536
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Retention index, connectivity index and Van der Waals' volume of alkanes (GLC) (1982)
    Springer
    Chromatographia 15 (1982), S. 521-524 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Retention index ; Connectivity index ; Van der Waals' volume ; Alkanes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The relationships between retention index and Van der Waals' volume and between retention index and connectivity index have been studied for 58 different alkanes (C1−C9) on squalane. The correlation coefficient for the former is higher than for the latter. From these equations a linear relationship between Van der Waals' volume and connectivity index is obtained which indicates that the two parameters are equivalent. A simple method for calculating the Van der Waals' volume of alkanes is proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02260288
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    An apparatus for manufacturing flexible fused silica columns for gas liquid chromatography. Part I. The drawing process (1982)
    Springer
    Chromatographia 15 (1982), S. 569-574 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Capillary columns ; Fused silica capillaries ; Capillary drawing ; Glass capillaries
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A compact description is given of a simple and reliable method of drawing flexible fused silica capillary for gas chromatography. Some emphasis is given to the fact that the practices of drawing optical fibres should not be followed too slavishly so this leads to unnecessarily complicated and expensive equipment. Satisfactory capillary column silica tubing can be made with straightfoward extension of the method developed earlier for drawing thick walled capillary. A simple glass/silica hydrogen oxygen diffusion flame bumer is described for fusing the preform tubing at the draw point which is enclosed by a water cooled glass enclosure to trap evaporated silica and maintain the operation under dust free conditions. The uniformity of the capillary diameter is better than 5% which is adequate for most gas chromatographic purposes. The second part of the paper yet to be published will cover the methods developed for coating the capillary both internally and externally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02280376
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    New uses of thermionic ionization detectors in gas chromatography (1982)
    Springer
    Chromatographia 16 (1982), S. 107-111 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Thermionic ionization ; Catalytic flame ionization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A newly designed thermionic detector was operated in two modes of thermionic ionization detection (TID), and a third mode of catalytic flame ionization detection (CFID). Operating modes were varied by changing the composition of the electrically-heated thermionic/catalytic source, and the composition of gases supplied to the detector. A TID-2 source activated by a low concentration of Cs/ceramic was operated in a dilute H2/air environment and provided specific responses to nitrogen and phosphorus compounds. A TID-1 source activated by a high concentration of Cs/ceramic was operated in a N2 environment and provided very high specificities and picogram detectivities to compounds containing electronegative functional groups such as the NO2 group. A CFID source formed from Ni/ceramic was operated in a H2/air flame environment and provided universal responses to all organics with enhanced responses to some heteroatom compounds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02258879
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Noradrenergic axon terminals in the substantia gelatinosa of the rat spinal cord (1982)
    Springer
    Cell & tissue research 222 (1982), S. 359-378 
    Details
    ISSN: 1432-0878
    Keywords: Axon terminals ; Substantia gelatinosa ; Spinal cord ; Noradrenaline ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The noradrenergic terminals in the substantia gelatinosa of the dorsal horn of the cervical spinal cord of the rat were investigated by means of the histofluorescence technique and electron-microscopic cytochemistry using the glyoxylic acid-KMnO4 fixation technique. In accordance with the topographical distribution of fluorescent catecholaminergic fibers, noradrenergic terminals containing small granular vesicles were frequently observed electron microscopically in the outer layer of the substantia gelatinosa. These terminals were most frequently found to appose without showing typical synaptic features, small-caliber dendrites, spine apparatus, and rarely, large caliber dendrites. Only in a few cases, the noradrenergic terminals exhibited typical synaptic contacts with dendritic elements of small size. In addition, noradrenergic terminals apposed non-noradrenergic terminals containing small agranular vesicles. In rats bearing surgical lesions of the dorsal roots, no noradrenergic terminal were found in contact with the degenerated axon terminals in the substantia gelatinosa. These findings suggest that the noradrenergic afferents to the substantia gelatinosa may exert their influence on sensory transmission via dorsal horn cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Anomalous occurrence of immunoreactive calcitonin cells in the thymus of the rat (1982)
    Springer
    Cell & tissue research 222 (1982), S. 629-634 
    Details
    ISSN: 1432-0878
    Keywords: Calcitonin cells ; Anomaly ; Thymus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a study of the effect of pinealectomy on thyroid C-cell number, 8 animals out of 66 were found to have thymic tissue in close association with the thyroid. Cells containing immunoreactive calcitonin were found in all of the thyroids but in only one of the 8 pieces of thymus. These cells found in a piece of thymic tissue associated with the right thyroid lobe were located immediately under the capsule and did not form or associate with follicles. Unlike the other animals the rat with thymic calcitonin cells had an unequal distribution of C-cells between the left and right thyroid lobes, but the total number of thyroidal C-cells was the same as that of the other rats. Since the thymus proper was not examined in these 66 animals, ten additional rats were taken for such a study. Thyroid-associated thymic tissue was found in three of these, but none of these thymi showed any immunoreactive cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213860
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    The autonomic innervation of rat jugular vein (1982)
    Springer
    Cell & tissue research 222 (1982), S. 691-693 
    Details
    ISSN: 1432-0878
    Keywords: Jugular vein ; Histochemistry ; Adrenergic innervation ; Cholinergic innervation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The autonomic innervation of rat jugular vein was studied using glyoxylic acid fluorescence and acetylcholinesterase histochemical methods. The rat jugular vein is provided with both adrenergic and cholinergic nerve fibers organized in plexuses located at the adventitial-medial border. The existence of these nerve plexuses does not seem to support biochemical findings that suggest a lack of innervation in the rat jugular vein and which propose this blood vessel as a model for the analysis of drug-smooth muscle cell interaction without the interference of neuronal uptake mechanisms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213867
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Immunocytochemical localization of substance P in the neurohypophysis and hypothalamus of the mouse compared with the distribution of other neuropeptides (1982)
    Springer
    Cell & tissue research 223 (1982), S. 533-544 
    Details
    ISSN: 1432-0878
    Keywords: Substance P ; Immunocytochemistry ; Neurohypophysis ; Hypothalamus ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Substance-P immunoreactivity has been located in semithin sections of mouse hypothalami and pituitaries and compared with the distribution of other hypothalamic peptides. In the mouse, nerve fibres and terminals reacting with antibodies against substance P (SP) were detected both in the external zone of the median eminence (ME) and in the neural lobe of the pituitary. Immunoreactive SP (ISP) axons of the ME did not react with antibodies against other peptides, i.e. arginine-vasopressin (AVP), oxytocin (OT), somatostatin and enkephalin, and were also negative with an antibody to serotonin. In the neural lobe, SP immunostaining occurred in AVP but not in OT axons. In the hypothalamus, ISP axons were widespread but conspicuously lacking in areas containing AVP neurones, i. e. in the suprachiasmatic nucleus and the clusters of AVP cells in the SO and PV nuclei. In contrast, multiple ISP endings were seen in contact with OT neurones. Immunoreactive cell bodies, only detected after colchicine treatment, belonged to two distinct classes of neurones: 1) single AVP neurones of the SO and PV nuclei; 2) specific (staining only for SP) neurones, scattered or grouped in different areas of the hypothalamus, not showing relationship with any circumscribed nucleus. These results reinforce the opinion that SP can be released as a neurohormone into the vascular portal system and can directly affect the pars distalis. The presence of immunoreactive SP in the neural lobe, which has not been reported in species other than the mouse, may have a different physiological significance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218474
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Synaptic connections of substance P-immunoreactive nerve terminals in the substantia nigra of the rat (1982)
    Springer
    Cell & tissue research 223 (1982), S. 469-486 
    Details
    ISSN: 1432-0878
    Keywords: Substantia nigra (rat) ; Substance P ; Striatonigral pathway ; Immunocytochemistry ; Synaptic vesicles ; Synapses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A monoclonal antibody that recognises the C-terminal part of substance P was used to study immunoreactive structures in the substantia nigra by the unlabeled antibody, peroxidase-antiperoxidase procedure. Immunoreactivity was present in nerve fibres in all parts of the substantia nigra, particularly in the pars reticulata and pars lateralis. Electron microscopically two types of bouton immunoreactive for substance P were found: Type 1 contained large electron-lucent vesicles, occasional large granulated vesicles and formed symmetrical synapses with dendrites. Type 2 boutons contained smaller, round electron-lucent vesicles, many large granular vesicles and formed asymmetrical synapses (having prominent postjunctional dense bodies) with dendrites and perikarya. Immunoreactive fibres with varicosities that had been identified light microscopically were studied in serial sections in the electron microscope. Each identified varicosity contained synaptic vesicles and formed a single synapse. An individual fibre formed boutons of only one kind (type 1 or type 2) and could form multiple synapses with the same neuron. Thus, an identified fibre in the pars compacta had eight varicosities, each of which was in synaptic contacts (type 2) with the dendrites or soma of the same neuron. The results are consistent with the concept that substance P is a synaptic transmitter in the substantia nigra and indicate that neurons in this region may receive a significant input from substance P-containing afferents, and that there are at least two types of such afferent fibres.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218469
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Morphological studies on neuroglia (1982)
    Springer
    Cell & tissue research 223 (1982), S. 493-506 
    Details
    ISSN: 1432-0878
    Keywords: Microglial cells ; TPPase ; NDPase ; Synapse ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron-microscopic survey of selectively stained microglial cells in the cerebral cortex of the rat reveals that the processes of this cell type often encircle axo-dendritic synapses. Enzyme-histochemical methods for thiamine pyrophosphatase (TPPase) or nucleoside diphosphatase (NDPase) were used for the selective marking of the microglial cells; TPPase and NDPase activities were observed in the plasma membrane of microglial cells. The synapses encircled by microglial processes displayed presynaptic structures containing round clear vesicles (50 nm in diameter) and a prominent thickening of the postsynaptic membrane. In vitro, the above-mentioned enzymatic activities were completely suppressed by neuroactive agents such as catecholamines and phenothiazine derivatives. Examination using enzyme-histochemical techniques suggests that a single enzyme may be responsible for both above-mentioned enzymatic reactions. The functional significance of microglial cells in the normal central nervous tissue is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218471
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Heterogeneity of tight junctions along the collecting duct in the renal medulla (1982)
    Springer
    Cell & tissue research 223 (1982), S. 603-614 
    Details
    ISSN: 1432-0878
    Keywords: Kidney ; Medullary collecting duct ; Rat ; Rabbit ; Tight junctions ; Freeze ; fracture electron microscopy ; Urinary concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The tight junctions along the medullary collecting duct in the kidneys of the rat and the rabbit were studied with freeze-fracture electron microscopy and quantitated according to the number of strands and the apico-basal depth (nm) of the junctions. The most elaborate tight junctions were found in the inner stripe of the outer medulla; rat: 10.6±0.8 strands and 205±24nm; rabbit: 11.6±2.4 strands and 291±55 nm. The elaboration of the tight junctions decreased continuously towards the papillary tip. Inner zone I; rat: 9.3±2.6 strands and 186±38nm, rabbit: 9.5±2.3 strands and 247±59nm. Inner zone II; rat: 7.1±2.2 strands and 129±32nm, rabbit: 8.5±1.4 strands and 199±26nm. Inner zone III; rat: 6.0±1.6 strands and 111 + 19 nm, rabbit: 7.0±1.5 strands and 183±43 nm. In the inner zone III comprising the papillary tip tight junctions with only 1–3 strands were not infrequently seen. Preliminary findings in the kidney of the golden hamster indicate a similar decline of junctional tightness along the collecting duct. These morphological observations suggest that the permeability of the paracellular pathway of the medullary collecting duct increases towards the tip of the papilla, especially in the rat. The functional implications for the medullary recycling of urea and electrolytes, and for the urinary concentrating mechanism are discussed. In addition, the tight junctions of the papillary epithelium are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218480
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Immunocytochemical localization of progesterone-binding protein (PBP) in guinea-pig placental tissue (1982)
    Springer
    Cell & tissue research 223 (1982), S. 627-639 
    Details
    ISSN: 1432-0878
    Keywords: Immunocytochemistry ; Progesterone-binding protein (PBP) ; Placenta ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cellular localization of progesterone-binding protein (PBP) in the guinea-pig placenta was studied by use of immunocytochemical procedures. Within the chorioallantoic placenta, a strong positive reaction was observed in the interlobar and marginal trophoblast from the third week of gestation to term. PBP was localized in the cytoplasm of the syncytiotrophoblast, and the nuclei were never stained. At the ultrastructural level, the immunoreaction was associated with the rough endoplasmic reticulum, the Golgi apparatus and the perinuclear space. No deposits were seen in any other cell organelles. This localization strongly suggests that the interlobar syncytium is related to PBP synthesis. In the labyrinth, a weak immunoreaction was observed by light microscopy around some blood lacunae. At the ultrastructural level the dense deposits were localized in vesicles located near the maternal lacunae. The distribution of PBP was also studied by light microscopy in other tissues from pregnant guinea-pig. No PBP, or PBP-like material, was detected inside cells from liver, muscle, heart, lung, kidney, ovary, and uterus. A weak immunoreaction for PBP was detected in vascularized zones of these organs. These observations strongly suggest that PBP, a protein related to gestation in the guinea-pig, is elaborated by the placental tissue of this hystricomorph rodent. PBP is the first steroid-binding plasma protein shown to be of extrahepatic origin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218482
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Postnatal appearance of luteinizing hormone-releasing hormone (LHRH)-like material in the pineal gland of the rat (1982)
    Springer
    Cell & tissue research 223 (1982), S. 695-698 
    Details
    ISSN: 1432-0878
    Keywords: Pineal gland ; Luteinizing hormone-releasing hormone (LHRH) ; Immunocytochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunoreactive luteinizing hormone-releasing hormone (LHRH)-like material has been demonstrated in the pineal gland of the adult rat. The objective of the present study was to examine the ontogenetic development of this LHRH-like substance in the rat pineal with the peroxidase-antiperoxidase (PAP) method of Sternberger. LHRH-like immunoreactive material was not observed in pineal glands of newborn rats. The amount of material increased progressively from the 6th–12th day of postnatal development. On day 12, the amount of LHRH-like immunoreactivity was consistent and comparable in all pineal glands of male and female animals examined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00218488
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Quantitative immunocytochemical studies on the gonadotrophs isolated from the pituitary of the male rat (1982)
    Springer
    Cell & tissue research 224 (1982), S. 137-144 
    Details
    ISSN: 1432-0878
    Keywords: Gonadotrophs ; Male rats ; Immunocytochemistry ; Cytophotometry ; Image analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Quantitative studies on the population of the gonadotropic cells in the pituitary of adult male rats were performed after trypsic dissociation of the pituitary glands and immunoenzymatic staining with anti-β-LH or anti-β-FSH antisera. Number, area and extinction of labelled cells were measured by use of an image analyser and a cytophotometer. The gonadotrophs represent approximately 14% of the pituitary cells. The mean area of gonadotrophs is significantly larger after staining with anti-β-LH serum than after staining with anti-β-FSH serum. Planimetric measurement of the gonadotrophs reveals their variability in size ranging between 30 and 160 μm2. Moreover, the size distribution depends on the staining serum used: more numerous small-sized cells (〈75 μm2) are stained with anti-β-FSH serum than with anti-β-LH serum, which conversely stains more numerous large-sized cells. Cytophotometric measurements indicate that immunostaining varies greatly among cells of the same size class and that the staining intensity appears to increase according to the cell size. These results emphasize the morphofunctional heterogeneity of the gonadotropic cell population.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217273
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    The pinealocyte nucleolus (1982)
    Springer
    Cell & tissue research 224 (1982), S. 195-206 
    Details
    ISSN: 1432-0878
    Keywords: Pinealocytes ; Nucleolus ; Rat ; Ultrastructure ; Twenty-four-hour changes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An ultrastructural and morphometric analysis was made of the nucleolar components in pinealocytes of 40 male Fischer rats sampled at eight times in an LD 12∶12 photoperiod cycle. Comparisons of results from the eight times showed variation in estimated mean volume of the granular component of ±29%, and of the fibrillar component ±11%, in relation to daily means. Peaks in mean volume of total nucleolus and its granular component occurred at 1 h of light. Near maximal and minimal mean volumes of the fibrillar component both occurred during both light and dark. Fibrillar centers (nucleolar organizer regions) of different sizes were found at all sampling times. It is concluded that temporal patterns in 24-h changes in the nucleolar components are most prominent in the granular component, and are more complex than suggested by changes in total nucleolar size or mean dimensions, and than represented by a simple biphasic circadian rhythm. Examples of different stages in the migration of the granular component, and of possible sites of nucleo-cytoplasmic transfer of nucleolar material, are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00217279
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Studies of hCG binding and endocytosis in rat ovary by ultrastructural immunocytochemistry (1982)
    Springer
    Cell & tissue research 224 (1982), S. 647-653 
    Details
    ISSN: 1432-0878
    Keywords: hCG binding sites ; Endocytosis ; Ovary ; Ultrastructural immunocytochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Localization of hCG binding sites and the process of endocytosis in pseudopregnant rat ovaries were investigated by indirect electron-microscopic immunocytochemistry. Immature female rats were treated with pregnant-mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) to induce ovarian luteinization. Eight days after priming with PMSG-hCG and 1–6 h before sacrifice the animals were given another injection of hCG to bind the receptors. Receptor sites to hCG localized by reaction product were present in most luteal cells, but not in primary follicular cells. The receptor sites were distributed on luteal cell surfaces facing interstitial spaces. Endocytotic pits containing hCG binding sites were rarely seen 1 h after hCG injection. At 2 h, hCG and presumably its receptor were taken up within endocytotic vesicles with the evidence of reaction product coated on the vesicle wall. With time, fusion of endocytotic vesicles with lysosome occurred and the reaction product appeared in phagolysosomes. The reaction product was localized on phagolysosomal inner surface or in free granular form. These findings suggest that hCG and its receptors were internalized through endocytotic pits and endocytotic vesicles and delivered to lysosomes probably for degradation. An additional experiment for localization of acid phosphatase was also performed to delineate the lysosomes and phagolysosomes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213759
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Cerebrospinal fluid-contacting neurons and other somatostatin-immunoreactive perikarya in brains of tadpoles of Xenopus laevis (1982)
    Springer
    Cell & tissue research 224 (1982), S. 693-697 
    Details
    ISSN: 1432-0878
    Keywords: Somatostatin ; Immunocytochemistry ; CSF-contacting neurons ; Hypothalamus ; Xenopus laevis, tadpoles ; Amphibia, Anura
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In untreated tadpoles of Xenopus laevis, stage 60 (Nieuwkoop and Faber 1956), somatostatin-immunoreactive perikarya and fiber networks are already discernible in the pallium and the septum, as well as in the anterior and posterior hypothalamus. In addition, somatostatin-immunoreactive cerebrospinal fluid (CSF)-contacting neurons were found in the periventricular gray of the most caudal division of the ventral tuber cinereum. The results are discussed with respect to the inhibitory influence of the system of CSF-contacting and other somatostatin-immunoreactive neurons on the anterior pituitary and other target sites, especially during the climax of metamorphosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00213765
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Localization of immunoreactive prolactin in ependyma and circumventricular organs of rat brain (1982)
    Springer
    Cell & tissue research 225 (1982), S. 79-93 
    Details
    ISSN: 1432-0878
    Keywords: Immunoreactive prolactin ; Immunocytochemistry ; Circumventricular organs ; Choroid plexus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunoreactive prolactin (IMP) has been localized in the male rat brain using the soluble peroxidase-anti-peroxidase (PAP) technique. In normal untreated animals, reaction product was seen in choroid plexus (CP) and in ependymal cells of the ventricular lining with heaviest concentrations of positively staining cells in the 3rd ventricle near the subcommisural organ (SCO), in the lateral ventricles near the subfornical organ (SFO), and in the 4th ventricle near the area postrema (AP). IMP was also present in numerous ependymal cells resembling tanycytes in the cerebral aqueduct, central canal of the spinal cord at the level of the AP, the organum vasculosum of the lamina terminalis (OVLT) and the floor of the infundibular recess. Immunoreactive cells resembling neurons were localized within the substance of the AP, SCO, and OVLT. IMP was also present in fibers of the zona externa of the median eminence and infundibular stalk; a few cells of the pars tuberalis contained reaction product. Hypophysectomized rats and bromocriptine-treated rats exhibited a similar staining pattern except that bromocriptine treatment eliminated IMP from most CP cells. Hypophysectomy, bromocriptine or estrogen treatment enhanced staining for IMP in cells of the pars tuberalis; estrogen treatment or hypophysectomy produced an increase in the number and distribution of immunoreactive cells as well as increased density of reaction product in cells of the medial habenular nucleus. The functional relevance of prolactin in these locations in the brain, the possible routes of transport of prolactin from the pituitary gland to the central nervous system, and the strong suggestion of extra-pituitary sites of synthesis of a prolactin-like hormone are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00216220
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Distribution of sensory neurones of the pudendal nerve in the dorsal root ganglia and their projection to the spinal cord (1982)
    Springer
    Cell & tissue research 226 (1982), S. 555-564 
    Details
    ISSN: 1432-0878
    Keywords: Pudendal nerve ; Sensory neurones ; Spinal ganglion ; Transganglionic labelling (HRP) ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphology and distribution of the sensory neurones of the pudendal nerve within the spinal ganglia of rats were investigated by use of horseradish peroxidase (HRP). The labelling was visualized in diaminobenzidine (DAB) or tetramethyl-benzidine (TMB)-stained sections. Injection of HRP directly into the pudendal nerve labelled perikarya predominantly in the sixth lumbar DRG (L6). Following injection of HRP into the scrotal skin, however, additional cells were labelled in L5 and SI. Labelling was invariably unilateral. Approximately equal numbers of small (〈30 μm) and large neurones (〉40 μm) were labelled following subcutaneous injections although injections into the nerve marked twice as many small cells as large cells. This suggests that, in the rat, most of the small-diameter fibres within the pudendal nerve ascend through L6. Although a cluster of neurones was observed in one experiment, the remaining 25 experiments did not reveal any somatotopic arrangement since the labelled perikarya were distributed evenly throughout the ganglion. Similar numbers of retrogradely labelled neurones (somatopetal transport of the tracer) were observed in both DAB- and TMB-stained sections, although TMB allowed the demonstration of anterograde (somatofugal) HRP transport by terminal labelling in the superficial laminae of the lumbar spinal cord, extending into laminae II–IV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214784
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Immunohistochemical localization of the luteinizing hormone releasing hormone (LHRH)-containing structures in the central nervous system of the domestic fowl (1982)
    Springer
    Cell & tissue research 227 (1982), S. 451-458 
    Details
    ISSN: 1432-0878
    Keywords: Domestic fowl ; Hypothalamus ; LHRH-neurosecretion ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The location of LHRH-containing neuronal elements was investigated in the domestic fowl by means of immunohistochemical techniques. LHRH antisera were raised against synthetic LHRH in the rabbit. The antiserum used in the present study cross-reacted with LHRH of mammalian and avian tissues. LHRH-immunoreactive perikarya are located in the preoptic and in the septal areas, and in the bulbus olfactorius; however, no LHRH-immuno-reactive perikarya were found in the tuberal part of the hypothalamus. LHRH-immunoreactive fibers course from these areas toward the median eminence mainly along the wall of the third ventricle in the form of a periventricular network. Originating from the same cell groups other fibers run caudally immediately above the optic chiasma, forming the median bundle of the tractus preoptico-infundibularis. The third bundle running toward the OVLT is named the tractus preoptico-terminalis. In addition to these structures, LHRH-containing fibers and terminals were also present in different regions of the limbic system, in the dorsal part of the hippocampus, in the tuberculum and bulbus olfactorius, as well as in the optic lobe, nuclei commissurales tectales, organon subcommissurale, periaqueductal area, and pars ventralis mesencephali. The general distribution of the LHRH system in the chicken corresponds principally to that described previously in rodents (Sétáló et al. 1976, 1978). However, some subtle differences were demonstrated between the location of the LHRH system in birds and mammals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210899
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Neurophysin pathways in the normal and hypophysectomized rat (1982)
    Springer
    Cell & tissue research 227 (1982), S. 93-112 
    Details
    ISSN: 1432-0878
    Keywords: Neurophysins ; Immunocytochemistry ; Age-dependent changes ; Hypophysectomy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The hypothalamo-extrahypophyseal neurophysin pathways (HEH) and the three hypothalamic nuclei secreting neurophysins, the supraoptic (SON), paraventricular (PVN) and suprachiasmatic (SCN) nuclei, of normal and hypophysectomized rats were studied by application of the immunoperoxidase procedure. Eight well-defined HEH pathways were recognized. Their main sites of projection were: lateral septum and subfornical organ (1 and 2); tractus diagonalis (3); medial nucleus of the amygdala and lateral ventricle (4); nucleus periventricularis thalami, nucleus habenulae lateralis and periaqueductal gray (5); periaqueductal gray, pineal organ, collicular recess and subependymal region of the fourth ventricle (6); dorsomedial nucleus and premammillary area (7); perimammillary region, corpus trapezoideum, ventral surface of medulla oblongata, nucleus tractus solitarii, nucleus commissuralis, substantia gelatinosa and formatio reticularis lateralis of the medulla oblongata and spinal cord (8). Neurophysin fibers of unknown origin were found in the frontal cerebral cortex. It was noted that in pathway 5 the amount of immunostainable material undergoes changes with age. The three neurophysin-secreting nuclei reacted differently following hypophysectomy. Among the HEH pathways the only one that seemed to be affected by hypophysectomy was that innervating the lateral septum. It is suggested that the neurons that survive hypophysectomy either do not project to the neural lobe or, alternatively, display axon collaterals projecting outside the neural lobe. Such a neuronal population could be the origin of the HEH pathways.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206334
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Routine overnight starvation and immunocytochemistry of hepatocyte albumin content (1982)
    Springer
    Cell & tissue research 227 (1982), S. 423-427 
    Details
    ISSN: 1432-0878
    Keywords: Liver (Rat) ; Albumin ; Metabolism ; Hepatocytes ; Immunocytochemistry ; Nutrition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The indirect immunoperoxidase method was used to identify albumin in hepatocytes of rats before and after periods of starvation. All hepatocytes in fed rats contained a relatively large amount of nascent albumin. Overnight fasting reduced the number of hepatocytes with a large amount of albumin to primarily those surrounding terminal hepatic venules. These were estimated to be about 30% of the population. The other cells had only a slight amount of albumin. After 48 h of fasting all hepatocytes contained a low level of albumin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00210896
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...