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?

  • 1
    Electronic Resource
    Electronic Resource
    Human ecology 10 (1982), S. 477-494 
    ISSN: 1572-9915
    Keywords: menopause ; human evolution ; inclusive fitness ; longevity ; aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Ethnic Sciences
    Notes: Abstract To postulate an evolutionary advantage of the menopause is to address the paradox of how natural selection can favor cessation of reproduction. To do this, menopause is examined with reference to four criteria: (1) its species-specificity and genetic basis; (2) its evolutionary history; (3) its selective advantage in the context of human longevity; and (4) its possible role in human evolution. A brief review of the literature reveals that the first two criteria are satisfied. The third criterion is supported by a study of four New England genealogies which demonstrated that, among 1,890 women born between 1675 and 1874, those who died postmenopausally had greater inclusive fitness than those who died premenopausally. The finding that females with postmenopausal longevity also had greater fertility may represent age-independent improvement in survival. A theory for evolution of the menopause is advanced, based on the observation that population growth via decreased birth spacing among mobile hominid groups would be enhanced by the presence of postreproductives who served as infantcarriers.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1434-1948
    Keywords: 2,2′-Bipyridines ; Chelate complexes ; Hydrogen bonding ; π-π stacking ; Crystal structure ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new synthetic route for the synthesis of 5,5′-diamino-2,2-bipyridine (5) based on the coupling of 2-chloro-5-aminopyridine in the presence of NiCl2 × 6 H2O/PPh3/Zn in dimethylformamide is described. The reactions of the potentially ambidentate ligand 5 with salts of the transition metals Mn, Fe, Ni, Cu, Zn, Ag, and Cd gave a variety of 13 metal-ligand complexes depending on the anion, the crystallization conditions and the metal-to-ligand ratio. The complexes obtained were characterized by thermal analyses, NMR including 113Cd-NMR, IR, and for the iron complex 57Fe-Mößbauer spectroscopy. The structure of eight of the compounds was elucidated by X-ray crystallography. All of these metal complexes show a bipyridine-metal coordination. The amino functionality was never involved in metal coordination. The intermolecular arrangement is dictated by hydrogen bonding from the amino functionality and by π-π stacking of the bipyridine rings.Supporting information for this article is available on the WWW under or from the author.
    Additional Material: 8 Ill.
    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...