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41.
42.
Social attachment is vital for human health and welfare. Recent experimental evidence in humans has identified the role of neuroactive hormones, especially the peptide oxytocin, in mediating trusting behaviors. Herein, we test if the endocrinological basis for trust between humans scales up to the country level. Trust pervades nearly every aspect of our daily lives, yet survey data on trust show substantial variation across countries. Using 31 measures of biological, social, and environmental factors associated with hormone levels for a sample of 41 countries, we find that two classes of factors are related to trust: consumption of plant-based estrogens (phytoestrogens), and the presence of environmental conditions that include measures of estrogen-like molecules. Our findings provide preliminary evidence that interpersonal trust at the country level may be related to the intake of neuroactive hormones. 相似文献
43.
Georg Steinhauser Johannes H. Sterba Karin Poljanc Max Bichler Karl Buchtela 《Journal of trace elements in medicine and biology》2006,20(3):119-153
In this study, 18 partly commercially available samples of rock salt from Austria, Germany, Pakistan, Poland, Switzerland, and Ukraine were investigated with respect to their content of trace elements using instrumental neutron activation analysis. Elements detected were Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, La, Mn, Na, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, and Zn, some of them only in individual cases. An estimation of the bioavailability of these trace elements was performed by dissolving an equivalent of the sodium chloride samples in diluted hydrochloric acid (simulating stomach acid), filtering off the insoluble components, and analyzing the evaporated filtrate. It could be shown that in most cases bioactive trace elements like Fe can be found in rock salt in the form of almost insoluble compounds and are therefore not significantly bioavailable, whereas thorium, for example, was partly bioavailable in two cases. A significant contribution to the recommended daily intake of metal trace elements by using rock salt for nutrition can be excluded. 相似文献
44.
Ohne ZusammenfassungProceedings of the Meetings of Saturday September 26, 1908.Die vorliegende Übersetzung, zu der Herr Prof. Went mich gütigst autorisierte, rechtfertigt sich durch die in theoretischer, ganz besonders aber in methodologischer Hinsicht überaus wichtigen Ergebnisse Blaauws. Die Untersuchung bestätigt zunächst ein Gesetz, das der Übersetzer für die Abhängigkeit der Präsentationszeit von der Lichtintensität festgestellt hat (die diesbezügliche Abhandlung war Herrn Prof. Went zur Zeit, als er dieses Referat schrieb, noch nicht zu Gesicht gekommen), verfolgt aber diese Gesetzmäßigkeit innerhalb wesentlich weiterer Grenzen. Die Feststellung ganz besonders, daß bei entsprechend intensiver Beleuchtung die Präsentationszeit bis auf 1/1000 Sekunde sinkt, zusammengehalten mit den Tatsachen der feinen Unterschiedsempfind-lichkeit der Pflanzen (Wiesner) und der außerordentlich kurzen Perzeptions-zeit (Fitting), muß die reizphysiologische Methodik reformieren und sie zu ebenso exaktem Arbeiten anspornen, wie es bei psychophysischen Experimenten längst der Fall ist. 相似文献
45.
Paul Mellars 《Evolutionary anthropology》2005,14(1):12-27
Few topics in palaeoanthropology have generated more recent debate than the nature and causes of the remarkable transformation in human behavioral patterns that marked the transition from the Middle to the Upper Paleolithic in Europe. 1 - 11 Those of us who have argued for an effective technological and cultural “revolution” at this point in the Paleolithic sequence have emphasized three main dimensions 1 , 2 , 9 , 11 - 14 : the wide range of different aspects of behavior that appear to have been affected (Fig. 1); the relative speed and abruptness with which most of these changes can be documented in the archeological records from the different regions of Europe; and the potentially profound social and cognitive implications of many of the innovations involved. Most striking of all in this context is the abrupt appearance and proliferation of various forms of perforated animal teeth, shells, beads, and other personal ornaments, and the even more dramatic eruption of remarkably varied and sophisticated forms of art, ranging from representations of male and female sex organs, through the highly stylized animal and combined animal‐human figures from southern Germany, to the striking wall paintings of the Chauvet Cave. 8 , 15 - 18 One might add to this the similar proliferation of more enigmatic but potentially equally significant abstract “notation” systems on bone and ivory artifacts. 19 To describe the Upper Paleolithic revolution in Europe as reflecting preeminently an explosion in explicitly symbolic behavior and expression is in no sense an exaggeration, as most prehistorians would now agree. We are probably on safe ground in assuming that symbolic behavior and expression of this level of complexity would be inconceivable in the absence of highly structured language systems and brains closely similar, if not identical to, our own. 5 , 17 , 20 - 28 . 相似文献
46.
J T Streelman S A Karl 《Proceedings. Biological sciences / The Royal Society》1997,264(1384):1011-1020
Fifteen per cent of all living fishes are united in a single suborder (Labroidei) and display a dazzling array of behavioural and ecological traits. The labroids are considered monophyletic and members share a pharyngeal jaw apparatus (PJA) modified for crushing and processing prey. Outside of the explicitly functional PJA, there is no corroborative evidence for a monophyletic Labroidei. Here, we report the first molecular phylogenetic analysis of the suborder. Contrary to morphology-based phylogenies, our single-copy nuclear DNA data do not support labroid families as a natural group. Our data indicate that pharyngognathy has evolved independently among labroid families and that characters of the PJA are not reliable markers of perciform evolution. This work ''crushes'' conventional views of fish phylogeny and should engender novel concepts of piscine life history evolution. 相似文献
47.
One particular kind of structure offers possible explanations, for long-term memory, efficient consolidation of stored information
from the environment, clustering of data strings and multimodal functioning. It is a possible model for pieces of neural structure
and its use offers a uniform method for both studying and constructing an extensive class of mechanisms. 相似文献
48.
Paul John Beggs 《Biodiversity and Conservation》2012,21(14):3731-3734
Poleward and upward shifts in ranges in plant and animal species are amongst the most confident impacts of climate change on terrestrial ecosystems. While mountain tops have long been recognised as an important limit in this regard, the implications of the practice of mountaintop removal mining, i.e., acting counter to the upward shift of species, have yet to be considered. In regions where climate warming and mountaintop mining occur together, species face increased risk of range contraction and local extinction. 相似文献
49.
50.
The number of orientation, feeding and social calls emitted by pipistrelle batsPipistrellus pipistrellus Schreber, 1774 andP. pygmaeus Leach, 1825 was recorded throughout the night at eight different sites. Social calls were unaffected by weather variables,
whereas orientation calls and feeding buzzes were both significantly affected by cloud and temperature conditions. The number
of emissions of each call type was significantly different between sites, indicating that the bats used different sites for
different activities. Significant positive correlations between all three combinations of call types occurred only during
the middle of the night, corresponding with the nadir of flying insects. This suggests that bats were engaged in activities
other than feeding at this time, such as territory protection or mate attraction. 相似文献