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
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Changes in biochemical composition, lipid class and fatty acid contents were studied in the ovaries and midgut glands of the fiddler crabs Uca tangeri Eydoux during maturation. Wild females were caught during spring and early summer of 1992 in the Bay of Cádiz (southwest Spain), near the mouth of the San Pedro river. Protein and total lipid contents in the ovaries increased significantly from Stages III to IV, at the expense of total carbohydrate, which showed a large decrease during the same period. In the midgut gland, the protein content did not present any significant variation, whereas total lipids and total carbohydrates presented opposite up and down trends during maturation. In the ovary, total polar lipids increased significantly during the final phase of maturation (Stages III to IV), mainly due to the significant contribution of the phosphatidylcholine and phosphatidylethanolamine fractions. In contrast, total neutral lipids showed an upward trend throughout the whole maturation period, mainly due to significant increases of the triacylglycerol fraction. In the midgut gland, total polar lipids (mainly phosphatidylcholine) and total neutral lipids (mainly triacylglycerol) presented significant decreases from Stages II to III, the phase which preceded major increases in both polar and neutral lipids in the ovaries. Cholesterol content did not vary during maturation in either organ, in the ovary or midgut gland. Major fatty acids in the ovaries [16:0, 16:1 (n-7), 18:1 (n-9), 18:1 (n-7), 18:2 (n-6), 18:3 (n-3), 20:4 (n-6), 20:5 (n-3) and 22:6 (n-3)] did, however, accumulate significantly at later stages of maturation. It is noteworthy that arachidonic acid [20:4 (n-6)] content remained constant during all stages of maturation but decreased significantly in total polar lipids in the later phases of maturation. In contrast, eicosapentaenoic acid [20:5 (n-3)] increased significantly in all lipid fractions in the later stages, and docosahexaenoic acid [22:6 (n-3)] remained constant in the polar lipids and increased during later stages in the triacylglycerol fraction. Major fatty acids in the midgut gland lipids showed significant decreases from Stages II to III, just before the final period of maturation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Marine biology 71 (1982), S. 157-161 
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The cephalothorax length of the marine pelagic Copepoda Acartia clausi Giesbrecht, Temora longicornis (Müller), Centropages hamatus (Lilljeborg) and Pseudocalanus sp. was monitored at 15°C during prolonged cultivation through up to 55 filial generations and at different concentrations of food. The length of T. longicornis decreased considerably during the first 15 generations and remained rather constant thereafter. In the other species, body length increased slightly or remained almost constant. Genetic changes are probably involved. Food concentration influenced body size of all species, particularly C. hamatus, in which 80% of the natural size range may be explained by differences in food concentration. The idea that temperature is a dominant factor in determining the length of copepods should be reconsidered.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1211
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Interleukin-8 is a chemokine with a potent neutrophil chemoatractant activity. In humans, two different cDNAs encoding human IL8 receptors designated IL8RA and IL8RB have been cloned. IL8RA binds IL8, while IL8RB binds IL8 as well as other α-chemokines. Both human IL8Rs are encoded by two genes physically linked on chromosome 2. The IL8RA and IL8RB genes have open reading frames (ORF) lacking introns. By direct sequencing of the polymerase chain reaction products, we sequenced the IL8R genes of cell lines from four non-human primates: chimpanzee, gorilla, orangutan, and macaca. The IL8RB encodes an ORF in the four non-human primates, showing 95% – 99% similarity to the human IL8RB sequence. The IL8RA homologue in gorilla and chimpanzee consisted of two ORF 98% – 99% identical to the human sequence. The macaca and orangutan IL8RA homologues are pseudogenes: a 2 base pair insertion generated a sequence with several stop codons. In addition, we describe the physical linkage of these genes in the four non-human primates and discuss the evolutionary implications of these findings.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Algebra and logic 30 (1991), S. 310-327 
    ISSN: 1573-8302
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of radioanalytical and nuclear chemistry 136 (1989), S. 203-210 
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract The precipitation of uranyl ion with 2-hydroxy-1-naphthaldehyde /2H−1N=HL/ was studied. The solid complex /orange crystals/ was characterized by IR, UV-Vis spectra. Uranium was determined as U3O8 after calcination of the complex at 850°C /37.78% U experimental, 36.64% U calculated for C22H14O6U, UO2L2/. Using a statistical experimental design, the best conditions for quantitative precipitation were obtained. A gravimetric method for the determination of UO 2 2+ is proposed by weighing the complex after drying at 110°C.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 31 (1975), S. 153-154 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Resumen La administracion de 100 g de galactosa a 9 voluntarios sanos por via oral, demostro ser capaz de elevar la insulinemia, sin modificar la glucosa en sangre. Secundariamente se aprecio un descenso de los acidos grasos libres. La galactosa puede actuar directamente sobre el pancreas o a traves del intestino.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Applied physics 67 (1998), S. 611-613 
    ISSN: 1432-0649
    Keywords: PACS: 42.65; 42.70; 65
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: 3 Ga5O12 crystal when illuminated at the terbium ion resonance, becomes optically uniaxial. The optical axis is found to be along the beam-propagation axis. The origin of this symmetry breakdown is a thermal effect. Our observation of a conoscopic pattern is accounted for by a quadratic stress and refractive index distribution model. By spatial integration of the conoscopic pattern, the laser-induced stress birefringence variation as a function of the incident beam power is determined.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1572-8838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
    Notes: Abstract The pitting corrosion of copper in alkaline solutions in the presence of benzotriazole (BTA) was investigated. The presence of BTA shifts the breakdown (E b) and the repassivating (E p) potentials positively with respect to the blanks. However, the shift ofE p becomes smaller than that ofE b, particularly at pH9 and 11. Pitting corrosion involves the formation of crystallographic pits. The kinetics of the process fits a nucleation and growth mechanism involving instantaneous nucleation and 3D growth under charge transfer control. The spatial distribution of pits indicates that there is no marked influence of a pit on the nucleation and growth of other pits.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1573-6822
    Keywords: cell detection ; cell morphology ; cell lines ; drug effects ; image analysis ; neuronal cultures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract An automated system, TRAKCELL, was developed for the quantitation of cells in culture. It enabled cell counting, classification according to morphological cell characteristics and measurement of cell proliferation and differentiation. The system was tested on the toxic effect of ascorbic acid on rat brain catecholaminergic neurons in primary culture. In parallel, the effects of nerve growth factor, dexamethasone and forskolin on cell differentiation were studied using rat pheochromocytoma PC12 cells. The results show that the system permits rapid and reproducible measurements of cell density and of the morphological changes observed following various drug treatments.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Journal of optimization theory and applications 50 (1986), S. 109-128 
    ISSN: 1573-2878
    Keywords: Calculus of variations ; optimal control ; computing methods ; numerical methods ; boundary-value problems ; modified quasilinearization algorithms ; differential constraints ; nondifferential constraints ; general boundary conditions ; optimal initial choice of the multipliers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract This paper considers the numerical solution of the problem of minimizing a functionalI, subject to differential constraints, nondifferential constraints, and general boundary conditions. It consists of finding the statex(t), the controlu(t), and the parameter π so that the functionalI is minimized while the constraints are satisfied to a predetermined accuracy. The modified quasilinearization algorithm (MQA) is extended, so that it can be applied to the solution of optimal control problems with general boundary conditions, where the state is not explicitly given at the initial point. The algorithm presented here preserves the MQA descent property on the cumulative error. This error consists of the error in the optimality conditions and the error in the constraints. Three numerical examples are presented in order to illustrate the performance of the algorithm. The numerical results are discussed to show the feasibility as well as the convergence characteristics of the algorithm.
    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...