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Peritidal carbonate platform Lofer cycles have been regarded as a record of sea-level oscillations driven by variations in the earth's orbit. Fresh analysis of a newly measured 700?m thick section from the Steinernes Meer is presented here. Estimation of stratigraphic completeness indicates that this sequence is only 0.75–9.5% complete, strongly suggesting that Milankovitch patterns are not preserved. Analysis of cycle thickness-frequency distributions reveals an exponential pattern, strongly suggestive of aperiodic, random deposition rather than periodic deposition in response to orbital forcing. Evidence for the importance of autocyclic processes (e.g. lateral migration of inter- to supratidal mudbanks and subtidal areas) and syn-sedimentary tectonic downfaulting events within this already active Late Triassic extensional zone is presented.  相似文献   
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The primate Pan troglodytes troglodytes, a chimpanzee subspecies, has recently been defined as a natural animal host of the human immunodeficiency virus (HIV). Apes are traditionally hunted in Africa and are offered for sale in open-air meat markets. The bloody carcasses are regularly covered with blood-feeding flies, amongst them possibly the stable fly (Stomoxys calcitrans L.), a cosmopolitically occurring biting fly. This fly is the effective vector for the retrovirus causing equine leukemia. According to laboratory experiments, the infectivity of ingested HIV is not reduced in the regurgitates of this fly. These findings are combined to explain the mechanism for a possible primary transmission of HIV from ape to man.  相似文献   
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Meaningful human–nature interactions can counteract the extinction of experience and positively influence people’s nature relatedness, health and wellbeing. In this study, we explored urban wild food foraging to understand how best to enable human-nature interactions in cities by means of foraging. Using a structured questionnaire, a total of 458 residents of Vienna, Austria were surveyed. Sixty-four percent of visitors of public urban green spaces previously foraged for wild food species, whereas foraging frequencies were related to the targeted plant species and their life forms. People who foraged more frequently had greater nature relatedness, more childhood foraging experiences and lived on the outskirts of the city, but their socio-demographic backgrounds were heterogeneous. Social acceptance and lack of access to wild foods were perceived to be barriers. To promote nature relatedness through urban foraging, the legal framework, access to low-contamination foraging areas, availability of wild foods and social acceptance need to be improved.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01648-1.  相似文献   
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