ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Bulletin of environmental contamination and toxicology 48 (1992), S. 585-591 
    ISSN: 1432-0800
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Bulletin of environmental contamination and toxicology 50 (1993), S. 458-465 
    ISSN: 1432-0800
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 12 (1973), S. 323-330 
    ISSN: 1432-0827
    Keywords: Bone ; Osteoporosis ; Resorption ; Deer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des biopsies de côte, métacarpe et tibia sont prélevées chez des daims, cinq fois, pendant le cycle de croissance annuelle des andouillers. Les tissus sont étudiés par des méthodes histométriques ou densitométriques, suivies par l'analyse minérale à l'aide de la spectrophotométrie d'absorption atomique. Peu de remaniement s'observe dans le tissu osseux pendant la période de repos, mais pendant la période de croissance maximale des andouillers en juin, le remaniement osseux interne atteint son maximum. La résorption la plus élevée de 22,99% s'observe dans les côtes: elles est de 13,10% dans le métacarpe et 10,37% dans le métatarse. A l'automne, à la fin de la croissance des andouillers, on note une diminution du remaniement qui atteint des valeurs voisines de celle de la période de repos. Au niveau des côtes, les valeurs les plus faibles de poids de cendre, par unité de volume, s'observent au milieu de la période de croissance des andouillers, mais aucune variation cyclique de ces valeurs n'est trouvée dans le métacarpe, le métatarse et le tibia. Le pourcentage de calcium, magnésium et phosphore dans la cendre d'os ne varie pas pendant le cycle de croissance de l'andouiller. Il ne semble donc pas y avoir de changement de composition osseuse pendant les periodes de remaniement élevé.
    Abstract: Zusammenfassung Es wurden beim Wild in 5 Intervallen während des jährlichen Geweihwachstums-Cyclus folgende Biopsie-Proben entnommen: Rippe, Metacarpus, Metatarsus und Tibia. Die Gewebe wurden entweder mit histometrischen Methoden oder mit densitometrischen Messungen untersucht, welche durch eine Mineralanalyse mittels Atom-Absorptions-Spektrophotometrie ergänzt wurden. Während der Ruheperiode des Geweihwachstums erfolgte wenig Knochenneubildung; während der Hauptgeweihwachstumszeit im Juni hingegen erreichte die Knochenneubildung einen Höhepunkt. Die höchste Resorption von 22,99% erfolgte in den Rippen, beim Metacarpus waren es 13,10% und beim Metatarsus 10,37%. Beim Stillstand des Geweihwachstums im Herbst sank auch die Knochenneubildung wieder auf das niedere Niveau ab, das vor dem Geweihwachstum festgestellt wurde. Bei den Rippen zeigten sich die niedrigsten Werte des Aschgewichts per Volumeneinheit in der Mitte des Geweihwachstums; aber bei Metacarpus, Metatarsus und Tibia wurden für diese Werte keine cyclischen Veränderungen festgestellt. Der Prozentsatz von Calcium, Magnesium und Phosphor in der Knochenasche veränderte sich während des Geweihwaschstums-Cyclus nicht, was darauf hindeutet, daß die Zusammensetzung des Knochens während der Perioden erhöhter Neubildung gleich blieb.
    Notes: Abstract Biopsy samples of rib, metacarpus, metatarsus and tibia were obtained from deer at five intervals during the annual antler growth cycle. Tissues were examined by either histometric methods or by densitometric measurements followed by mineral analysis using atomic absorption spectrophotometry. Little remodelling occurred in bones during the period of antler quiescence, but during the peak of antler growth in June, internal bone remodelling reached a peak. The highest resorption of 22.99% occurred in ribs with lower levels of 13.10% for metacarpus and 10.37% for metatarsus. At the cessation of antler growth in the fall, remodelling again decreased to the low level found preceeding antler growth. In ribs lowest values of ash weight per unit volume occurred during the middle of antler growth but no cyclic variations were found for these values in metacarpus, metatarsus and tibia. Percentage of calcium, magnesium and phosphorus in bone ash did not vary during the antler growth cycle indicating no change in bone composition during periods of high remodelling.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Throughout 1981, the first routine collections of a variety of fish were made under the McMurdo Ice Shelf near White Island, Antarctica. Estimates of their local biomass were calculated using food consumption patterns of resident seals. Since no significant primary production occurs at White Island, the resident fauna must be maintained by a large nutrient influx from the Ross Sea.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-2048
    Keywords: Diffusion resistance ; Solanum ; Suberin ; Trichloroacetate ; Waxes ; Wound-healing tissue
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Combined gas chromatography-mass spectrometry showed that C21, C23, and C25 n-alkanes accumulated in the suberized layers during wound healing of cores of potato tuber tissue. Treatment (10 min) of freshly-cut tissue with trichloroacetate (TCA), an inhibitor of fatty-acid chain elongation, severely inhibited accumulation of hydrocarbons and fatty alcohols associated with the suberized layer in the wound healing tissue (maximum inhibition at 4 mM) but had very little effect on the deposition of the major aliphatic components of the suberin polymer. This preferential inhibition of wax synthesis resulted in severe inhibition of the development of diffusion resistance of the tissue to water vapor. These results strongly indicate that the waxes associated with the suberin polymer, rather than the polymer itself, consitute the major diffusion barrier formed during wound healing. Electron-microscopic examination showed that inhibition of wax synthesis by TCA disrupted the formation of the lamellar structure of suberin specifically by preventing the formation of the light bands. This evidence strongly suggests that the light bands in the suberin complex are composed of waxes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Water turnover rates were measured in gentoo and macaroni penguins breeding sympatrically on South Georgia Island. At the time of this study, adult male macaronis were attending the nest while female macaronis and both sexes of adult gentoos were making regular foraging trips to sea and returning to feed their chicks. Both species feed principally on krill, Euphausia superba, although gentoos also feed on fish. The average water turnover rate in 2 fasting male macaronis was 12.5 ml·kg-1·day-1 with a half-time for water turnover of 36 days. The mean water flux rate in feeding birds was 155 ml·kg-1·day-1 in gentoos and 184 ml·kg-1·day-1 in macaronis. The half-times for water turnover were 2.8 days, and 2.6 days, respectively. The average metabolic rate of fasting macaronis calculated from water turnover rates was 5.6 W·kg-1 or 1.8 x the standard metabolic rate (SMR). In order to calculate prey consumption and average daily metabolic rate (ADMR) from water flux rates in feeding birds, it was assumed that a) the only sources of water are from metabolism and performed water in the diet and b) the composition of the diet is known. Based on the type of prey consumed, the calculated ADMR was 7.1 W·kg-1 or 2.6×SMR (n=5) for gentoos and 9.1 W·kg-1 or 2.9×SMR (n=3) for macaronis. The ADMR of female macaronis making regular trips to sea was 1.6 x greater than the fasting metabolism of males brooding the chick.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and computational fluid dynamics 6 (1994), S. 113-123 
    ISSN: 1432-2250
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract An overview of a joint numerical/experimental investigation of the dynamic structure of a low-speed buoyant jet diffusion flame is presented. The dynamic interactions between the flame surface and the surrounding fluid mechanical structures are studied by means of a direct numerical simulation closely coordinated with experiments. The numerical simulation employs the full compressible axisymmetric Navier-Stokes equations coupled with a flame sheet model. Counterrotating vortex structures both internal and external to the flame surface are seen to move upward along with flame sheet bulges. These buoyancy-driven dynamic features compare well with those observed experimentally by means of phase-locked flow visualizations over entire flame-flickering cycles. The flicker frequencies measured both computationally and experimentally also compare well. Other aspects of this investigation which are discussed include sudden jumps in flicker frequency with increasing coflow velocity and the utilization of background pressure changes to simulate gravitational force variations experimentally.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 160 (1991), S. 627-635 
    ISSN: 1432-136X
    Keywords: Phoca vitulina ; Swimming ; Metabolism ; Fuel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1. The turnover rates and oxidation rates of plasma glucose, lactate, and free fatty acids (FFA) were measured in three harbor seals (average mass=40 kg) at rest or during voluntary submerged swimming in a water flume at 35% (1.3 m·s-1) and 50% (2 m·s-1) of maximum oxygen consumption (MO2max). 2. For seals resting in water, the total turnover rates for glucose, lactate, and FFA were 23.2, 26.2, and 7.5 μmol·min-1·kg-1, respectively. Direct oxidation of these metabolites accounted for approximately 7%, 27%, and 33% of their turnover and 3%, 7%, and 18% of the total ATP production, respectively. 3. For swimming seals,MO2max was achieved at a drag load equivalent to a speed of 3 m·s-1 and averaged 1.85 mmol O2·min-1·kg-1, which is 9-fold greater than resting metabolism in water at 18°C. 4. At 35% and 50%MO2max, glucose turnover and oxidation rates did not change from resting levels. Glucose oxidation contributed about 1% of the total ATP production during swimming. 5. At 50%MO2max, lactate turnover and anaerobic ATP production doubled, but the steady state plasma lactate concentration remained low at 1.1 mM. Lactate oxidation increased 63% but still contributed only 4% of the total ATP production. Anaerobic metabolism contributed about 1% of the total ATP production at rest and during swimming. 6. The plasma FFA concentration and turnover rate inereased only 24% and 37% over resting levels, respectively, at 50%MO2max. However, the oxidation rate increased almost 3.5-fold and accounted for 85% of the turnover. The percentage of total ATP produced (21%) from FFA oxidation at 35% and 50%MO2max did not increase greatly over that at rest. 7. Dive duration decreased from 78 s while resting in water to 28 s at 50%MO2max. 8. The RQ ranged from 0.78 at rest to 0.74 at 50%MO2max, indicating that fat was an important source of energy during submerged swimming. 9. By adjusting breath-hold duration during strenuous underwater swimming, harbor seals are able to maintain an aerobic, fat-based metabolism.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 151 (1983), S. 171-174 
    ISSN: 1432-136X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1. Consistent with previous studies on adult seals, post-dive blood lactic acid (LA) concentrations in immature Weddell seals did not increase above resting levels after short voluntary dives (Fig. 1). 2. Following longer dives, peak blood LA values increased rapidly according to the duration of the dive (Fig. 1). 3. The peak post-dive blood LA concentration relative to dive duration demonstrate that there is a positive relationship between aerobic dive limit (ADL) and body size (Fig. 1 and 3). 4. The ADL for 130 to 145 kg seals was about 10 min, and it was 13 min for 185 to 205 kg seals (Fig. 1). 5. The calculation of the ADL from available oxygen stores correlates well with the lactate/endurance curve intercept, where peak post-dive LA concentration rises rapidly above resting levels as the dive duration increases in adult and immature animals (Table 2 and Fig. 3). 6. Of total dives, 4% of the dive durations exceeded the measured ADL in 130 to 145 kg seals and 8% in the 205 kg seal (Fig. 2). 7. Dive depths of immature seals did not exceed 315 m (Table 1).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-136X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The salient features of this study in the order of significance as we perceive them are: 1. Post-dive arterial lactic acid concentrations were at no time different from resting levels unless the previous dive exceeded 20 to 25 min (Fig. 5). 2. Peak lactate concentration was correlated to dive durations (Fig. 6). 3. Only 2.7% of the dives of free-ranging seals exceed 26 min (Table 3 and Fig. 7). 4. There was a notable drop in body temperature during prolonged dives to as low as 34.9°C (Table 2). 5. Arterial hemoglobin concentrations immediately after dives (22.7%) were significantly higher than concentrations in resting animals (17.4g%) (Fig. 3). 6. Blood glucose after dives always rose aboce resting levels. 7. pH was in the normal mammalian range except after very long dives; in these cases the pH fell as low as 6.8 (Fig. 4). 8. Blood gases were in the normal mammalian range, but based upon resting apneic values $$P{\text{a}}_{{\text{O}}_{\text{2}} } $$ may drop to remarkably low levels during prolonged dives.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...