Publications by authors named "G Hambrecht"

A large scholarship currently holds that before the onset of anthropogenic global warming, natural climatic changes long provoked subsistence crises and, occasionally, civilizational collapses among human societies. This scholarship, which we term the 'history of climate and society' (HCS), is pursued by researchers from a wide range of disciplines, including archaeologists, economists, geneticists, geographers, historians, linguists and palaeoclimatologists. We argue that, despite the wide interest in HCS, the field suffers from numerous biases, and often does not account for the local effects and spatiotemporal heterogeneity of past climate changes or the challenges of interpreting historical sources.

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Article Synopsis
  • Cattle body size has fluctuated significantly from the Neolithic period to the Early Modern Ages, with height decreasing by about 1.5 times before increasing again.
  • Evidence from haplotype analysis indicates that the PLAG1 mutation (Q), influencing body size and reproduction, is over 1,000 years old and surged in frequency in Northwestern European cattle from the 16th to the 18th centuries.
  • The Q mutation was later introduced into non-European cattle breeds in the 19th and 20th centuries, showcasing its significant impact on the modern cattle's body size through a genomic selection process.
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This paper identifies rare climate challenges in the long-term history of seven areas, three in the subpolar North Atlantic Islands and four in the arid-to-semiarid deserts of the US Southwest. For each case, the vulnerability to food shortage before the climate challenge is quantified based on eight variables encompassing both environmental and social domains. These data are used to evaluate the relationship between the "weight" of vulnerability before a climate challenge and the nature of social change and food security following a challenge.

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Seven aphasic and seven normal subjects (Ss) viewed and described 25 cartoon drawings. While Ss described individual pictures the experimenter provided one of three types of feedback: explicit feedback, for example, "Can you tell me anything else about it?"; false feedback, for example, asking a question about another picture; or implicit feedback, for example, "I can't find it." five types of responses (recodings) were tallied.

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We used gas chromatography/mass spectrometry to measure brain 12-HETE (12-Hydroxy-5,8,10,14-eicosatetraenoic acid) formation from endogenous arachidonic acid in different species and different brain regions and in isolated brain microvessels. When blood-free brain slices were incubated for 20 minutes we found that the rabbit and cat brain incubates contained little 12-HETE when compared to rat and mouse brain incubates. Further in vitro studies of various rat brain regions showed a generally even distribution of 12-HETE.

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