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
  • Springer  (885)
  • 1990-1994  (486)
  • 1985-1989  (387)
  • 1955-1959  (12)
Collection
Keywords
Publisher
Years
Year
  • 1
    facet.materialart.
    Unknown
    The design of the Tokamak Physics Experiment (TPX) (1993)
    Springer
    Details
    Publication Date: 1993-09-01
    Print ISSN: 0164-0313
    Electronic ISSN: 1572-9591
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    Electronic Resource
    Electronic Resource
    Effects of copper and zinc on two planktonic ciliates (1986)
    Springer
    Marine biology 92 (1986), S. 21-29 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The interactive effects of copper and zinc on two estuarine planktonic ciliates, Favella sp. and Balanion sp., were determined in seawater media in which the free metal ion activities were controlled by nitrilotriacetic acid (NTA) trace metal ion buffer systems. Cupric ion activities of 10-10 M caused abnormal motility in both ciliates in shortterm (5 h) tests, and cupric ion activities as low as 10-12.8 M decreased the growth rates of both species in longer-term experiments. In the short-term tests, zinc ion activity by itself did not affect the motility of the ciliates, but there were significant interactions between copper and zinc. In the longer-term experiments, the growth of Favella sp. was optimal at the lowest cupric ion activity (10-13 M) and the two lowest zinc ion activities (10-12 and 10-13 M) and the two lowest zinc ion activities (10-12 and 10-11 M), and copper and zinc inhibited growth at activities above these values. By contrast, optimal growth rate of Balanion sp. occurred at the highest zinc ion activity (10-10 M) and the lowest cupric ion activities (10-13 to 10-12 M) and growth rate was reduced at zinc ion activities ≦10-11 M. There was an antagonism between copper and zinc which was particularly pronounced in Balanion sp.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00392741
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Obligate mixotrophy inLaboea strobila, a ciliate which retains chloroplasts (1988)
    Springer
    Marine biology 99 (1988), S. 415-423 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The planktonic ciliateLaboea strobila Lohmann sequesters photosynthetically functional chloroplasts derived from ingested algae. The chloroplasts lie free in the cytoplasm and are most abundant just under the pellicle of the ciliate. The maximum rate of photosynthesis (Pmax) was 925 pg C ciliate-1h-1 (3.7 pg C pg chl.a -1h-1). At saturating irradiance, the amount of carbon fixed h-1 equaled 12.6% of the body carbon of the ciliate. To grow,L. strobila requires both light and algal food. In the absence of food, survival ofL. strobila is significantly longer in the light than in the dark. Based on ingestion rate and photosynthetic rate, we calculate that photosynthesis can make an important contribution to this ciliate's carbon budget even when algal food is plentiful.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02112135
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Uptake and depuration of organic contaminants by blue mussels (Mytilus edulis) exposed to environmentally contaminated sediment (1986)
    Springer
    Marine biology 91 (1986), S. 497-507 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Experiments were designed to expose blue mussels (Mytilus edulis) to contaminated sediment collected from Narragansett Bay, Rhode Island, USA in 1982. Measurements were taken to allow comparisons of the uptake and depuration of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In addition, concentration factors in the mussels were calculated separately against the dissolved and particulate phase concentrations and the results from the exposure and control systems were compared. Both PAHs and PCBs were rapidly accumulated by the mussels exposed to the contaminated sediment. After the mussels were transferred to control seawater, individual PAHs were depurated with half-lives ranging from 12 to 30 d. Individual PCBs showed depuration half-lives which ranged from 16 to 46 d. Concentration factors in the mussels calculated against the particulate phase concentrations were very different in the exposure and control systems. Concentration factors calculated using only the dissolved phase concentrations (bioconcentration factors) showed excellent agreement in the two systems, possibly an indication that the dissolved phase was the direct source of the contaminants accumulated by the mussels. The bioconcentration factors for PCBs were higher than those of PAHs when compounds with similar n-octanol/water partition coefficients were compared.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00392601
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Lipid composition and metabolic activities of benthic near-shore microbial communities of Arthur Harbor, antarctic peninsula: Comparisons with McMurdo Sound (1989)
    Springer
    Polar biology 9 (1989), S. 517-524 
    Details
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Benthic microbial communities of the Arthur Harbor area were described by analysis of their cell membrane phospholipid ester-linked fatty acids (PELFA) and metabolic rates. Analysis revealed a biomass averaging 6 nM (phospholipid) or 3.5×108 cells per gram dry weight (gdw) of sediment for the four sites. Only slight biomass differences were detected between the four peninsula sites. All Arthur Harbor sites were determined to have a biomass similar to the lowest amount reported for a previously described McMurdo Sound site at New Harbor. Community structure based on signature phospholipids indicated only slight differences between the four peninsula sites with greater relative amounts of diatom marker lipids at a deeper site. Bacterial biomarker lipids were also determined in relatively equal proportions for the four Arthur Harbor sites with only one site indicating a somewhat decreased proportion. Metabolic rates of sodium [14C]-acetate and methyl [3H]-thymidine incorporation into lipid and bacterial DNA respectively also indicated only slight relative differences in microbial communities of Arthur Harbor study sites. Lipid metabolism (14C-acetate) ranged between 6 and 12 (x104) DPM/g/h for the four sites with 8 being the average. Bacterial (excluding sulfate-reducing bacteria (SRB)) cell divisions per g per h indicated increased rates at a deeper site with 14×105, compared to the average (5×105) for the three remaining sites. Average estimated total bacterial (excluding SRB's) community turnover was on the order of 0.6%/h for the four sites. Metabolic rate comparisons of Arthur Harbor with those of previously determined McMurdo Sound indicated a somewhat increased lipid metabolism and an order of magnitude greater bacterial cell division rate at Arthur Harbor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00261036
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Environmental factors influencing decomposition rates in two Antarctic moss communities (1986)
    Springer
    Polar biology 5 (1986), S. 95-103 
    Details
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Rates of disappearance of dead material of Polytrichum alpestre and Chorisodontium aciphyllum from a moss turf community and of Drepanocladus uncinatus, Calliergon sarmentosum and Cephaloziella varians from a moss carpet community, measured using litter bags over 2 years, were 1.5% year-1. Decomposition potential, estimated using loss in tensile strength of cotton strips inserted into the different bryophytes on the two sites, was also low. Ranking the five plant species in order of decomposition potential, from highest to lowest, gave D. uncinatus, C. aciphyllum, C. sarmentosum, P. alpestre and C. varians. The time taken for the tensile strength of the cotton strips at depths of 1–3 and 4–6 cm beneath the surface to decline by 50% varied from 1–2 years under the first two species to 3–4 years beneath the last two species. The main causes of these slow rates were low temperatures, short active season and low pH. Differences in decomposition between species, sites and with depth were related to temperature, nutrient status, water content and anaerobic conditions. Variation in anaerobic conditions beneath D. uncinatus, C. sarmentosum and C. varians in the moss carpet resulted in wide variation of decomposition rate beneath these species and with depth beneath C. varians. The peat in the moss turf was aerobic and experienced higher temperatures, but the average decomposition rate was no higher than in the moss carpet, because the peat was of a poorer quality and had a lower pH.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00443381
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Band 3 antagonists, p-azidobenzylphlorizin and dids, mediate erythrocyte shape and flexibility changes as characterized by digital image morphometry and microfiltration (1994)
    Springer
    The journal of membrane biology 141 (1994), S. 91-100 
    Details
    ISSN: 1432-1424
    Keywords: Erythrocyte ; Cytoskeleton ; Cell deformability ; Anion transport inhibitors ; Band 3 ; Sickle cell disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Two nonpenetrating membrane probes, p-azidobenzylphlorizin (p-AzBPhz) and 4,4′-diisothiocyano-2,2′-stilbene disulfonate (DIDS), have been shown in earlier studies to induce dose-dependent changes in red blood cell (RBC) shape and volume at the same low concentrations that inhibit anion transport. In the present work, these ligand-induced morphology and rheology changes were studied using video digital image morphometry (VDIM) and microfiltration techniques. The results of these experiments corroborate our earlier investigation. RBCs were filmed using a Nomarski optics microscope with video camera attachment and cell size and shape changes were computer analyzed using VDIM. Low μm p-AzBPhz or DIDS levels caused collapse of the cell's biconcave structure and cell flattening occurred within 1–2 sec after drug exposure. Higher doses of either agent converted cells to a new steady-state in which a concurrent limited increase in erythrocyte volume and blunt membrane protrusions were produced. These changes were reversed in less than 2 sec by washing the drug from the membrane. Both ligands increased the deformability of RBCs in a dose-dependent manner as determined by filtration through Nuclepore polycarbonate filters (3 μm pore diameter). The improvement in deformability of drug-treated sickle cells was much more dramatic than for normal cells at low p-AzBPhz concentrations. These results support our earlier conclusions that the ligands, through a common interaction with band 3, induce volume-associated cytoskeletal alterations which lead to changes in morphology and flexibility.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00232877
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Effect of gibberellin biosynthesis inhibitors on shoot regeneration from hypocotyl explants of Albizzia julibrissin (1993)
    Springer
    Plant cell reports 13 (1993), S. 115-118 
    Details
    ISSN: 1432-203X
    Keywords: adventitious shoot formation ; gibberellic acid ; paclobutrazol ; prohexadione calcium ; tissue culture ; uniconazole
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Hypocotyl explants of Albizzia julibrissin were placed on Gamborg's B5 medium supplemented with various levels of paclobutrazol, uniconazole, prohexadione calcium, or GA3. Callus formation was evident within one week after placement of the explants on the culture media. Green nodule-like structures protruded from the distal end of the explants within 10 days and developed into shoots within a month. These shoots readily formed adventitious roots when placed on fresh culture medium. All three of the gibberellin biosynthesis inhibitors increased shoot formation compared to the control. The number of shoots per explants was increased 107, 79, and 168% by 0.3–0.4 μM paclobutrazol, uniconazole, and prohexadione calcium, respectively. In contrast to the gibberellin biosynthesis inhibitors, GA3 decreased shoot formation. These results indicate that modification of gibberellin status can have a strong impact on the number of shoots formed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235303
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Influence of growth regulators on somatic embryogenesis, plantlet regeneration, and post-transplant survival of Echinochloa frumentacea (1992)
    Springer
    Plant cell reports 11 (1992), S. 368-371 
    Details
    ISSN: 1432-203X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract After placement on Murashige and Skoog's basal medium supplemented with 3–5 mg/l 2,4-D, immature inflorescence expiants of Echinochloa frumentacea gave rise to three distinct types of callus: a) loosely arranged and soft; b) compact and translucent; c) compact, sticky and mucilaginous. Somatic embryo formation occurred in type ‘b’ callus in about 18–24 d. Callus types ‘a’ and ‘c’ did not produce somatic embryos. The highest percentage of cultures exhibiting somatic embryogenesis occurred on the medium containing 5 mg/l 2,4-D and 0.5 mg/l kinetin. Somatic embryos also formed directly on the inflorescence (without intervening callus formation) in about 15% of the expiants placed on this medium. The addition of paclobutrazol or uniconazole (0.25 or 1 mg/l) to the medium had no influence on the percentage of cultures exhibiting direct somatic embryogenesis, but paclobutrazol slightly increased the mean number of somatic embryos per culture. Many of the callus-derived somatic embryos germinated when subcultured on basal MS medium supplemented with kinetin. Addition of paclobutrazol or uniconazole to the culture medium at 0.25 or 1 mg/l decreased somatic embryo germination and shoot elongation but increased root length and leaf width. Both paclobutrazol and uniconazole increased survival of the plantlets following transplanting to soil. Increased post-transplant survival was accompanied by reduced water loss from plantlets produced on culture media containing triazoles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00233368
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Mediation of deep supercooling of peach and dogwood by enzymatic modifications in cell-wall structure (1991)
    Springer
    Planta 184 (1991), S. 254-260 
    Details
    ISSN: 1432-2048
    Keywords: Prunus ; Cornus ; Cold hardiness ; Supercooling ; Xylem parenchyma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Treatment of stem sections of peach (Prunus persica (L.) Batsch) and flowering dogwood (Cornus florida L.) with macerase, an enzyme mixture rich in pectinase, for 24–48 h resulted in a complete flattening of the low-temperature exotherm (LTE) as determined by differential thermal analysis (DTA). Ultrastructural analysis of macerase-treated tissue demonstrated a nearly complete digestion of the pit membrane (black cap and primary cell-wall) of nearly 100% of the xylem-parenchyma cells examined after 48 h of exposure to the enzyme. Additionally, the underlying amorphous layer was partially degraded in up to 57% of the cells examined. The macerase treatment had no visible effect on secondary cell-walls of xylem tissue. In contrast, treatment of stem tissue with cellulysin (mostly cellulase) resulted in a shift of the LTE to warmer temperatures as determined by DTA, and a digestion of only the outermost layer of the pit membrane in nearly 100% of the cells examined, with little or no effect on the underlying layers. Treatment of tissue with 25 mM sodiumphosphate buffer also resulted in a shift of the LTE to warmer temperatures but the shift was not as great as in cellulysin-treated tissue. The shift was associated with a partial degradation of the outermost layer of the pit membrane in dogwood (33–45% of the cells examined) but not in peach (3–7% of the cells). Collectively, the data indicate that pectins may be an integral structural element of the pit membrane and that this portion of the cell-wall, along with the underlying amorphous layer, play a major role in forming a barrier to water movement and growth of ice crystals. This barrier allows xylem parenchyma of some species of woody plants to undergo deep supercooling.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01102426
    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...