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Jacques Launay Bronwyn Tarr Robin I. M. Dunbar 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(10):779-789
Humans have developed a number of specific mechanisms that allow us to maintain much larger social networks than would be expected given our brain size. For our primate cousins, social bonding is primarily supported using grooming, and the bonding effect this produces is primarily mechanistically underpinned by the release of endorphins (although other neurohormones are also likely to be involved). Given large group sizes and time budgeting constraints, grooming is not viable as the primary social bonding mechanism in humans. Instead, during our evolutionary history, we developed other behaviours that helped us to feel connected to our social communities. Here, we propose that synchrony might act as direct means to encourage group cohesion by causing the release of neurohormones that influence social bonding. By acting on ancient neurochemical bonding mechanisms, synchrony can act as a primal and direct social bonding agent, and this might explain its recurrence throughout diverse human cultures and contexts (e.g. dance, prayer, marching, music‐making). Recent evidence supports the theory that endorphins are released during synchronised human activities, including sport, but particularly during musical interaction. Thus, synchrony‐based activities are likely to have developed due to the fact that they allow the release of these hormones in large‐scale human communities, providing an alternative to social bonding mechanisms such as grooming. 相似文献
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Anne-Sophie Charlotte Hieke Robin Brinkmeyer Kevin M. Yeager Kimberly Schindler Saijin Zhang Chen Xu Patrick Louchouarn Peter H. Santschi 《Marine biotechnology (New York, N.Y.)》2016,18(6):630-644
Sediments in the Houston Ship Channel and upper Galveston Bay, Texas, USA, are polluted with polychlorinated dibenzo-p-dioxins/furans (PCDD/F; ≤46,000 ng/kg dry weight (wt.)) with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener, contributing >50 % of the total toxic equivalents (TEQ) at most locations. We measured PCDD/F concentrations in sediments and evaluated the potential for enhanced in situ biodegradation by surveying for Dehalococcoides mccartyi, an obligate organohalide respiring bacterium. Dehalococcoides spp. (98 % similar to D. mccartyi) and 22 other members of the class Dehalococcoidia were predominant 16S ribosomal RNA (rRNA) phylotypes. Dehalococcoides spp. were also present in the active fraction of the bacterial community. Presence/absence PCR screening detected D. mccartyi in sediment cores and sediment grab samples having at least 1 ng/kg dry wt. TEQ at salinities ranging from 0.6 to 19.5 PSU, indicating that they are widespread in the estuarine environment. Organic carbon-only and organic carbon + sulfate-amended sediment microcosm experiments resulted in ~60 % reduction of ambient 2,3,7,8-TCDD in just 24 months leading to reductions in total TEQs by 38.4 and 45.0 %, respectively, indicating that 2,3,7,8-TCDD degradation is occurring at appreciable rates. 相似文献
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Rice endosperm is cost‐effective for the production of recombinant griffithsin with potent activity against HIV 下载免费PDF全文
Evangelia Vamvaka Elsa Arcalis Koreen Ramessar Abbey Evans Barry R. O'Keefe Robin J. Shattock Vicente Medina Eva Stöger Paul Christou Teresa Capell 《Plant biotechnology journal》2016,14(6):1427-1437
Protein microbicides containing neutralizing antibodies and antiviral lectins may help to reduce the rate of infection with human immunodeficiency virus (HIV) if it is possible to manufacture the components in large quantities at a cost affordable in HIV‐endemic regions such as sub‐Saharan Africa. We expressed the antiviral lectin griffithsin (GRFT), which shows potent neutralizing activity against HIV, in the endosperm of transgenic rice plants (Oryza sativa), to determine whether rice can be used to produce inexpensive GRFT as a microbicide ingredient. The yield of OSGRFT in the best‐performing plants was 223 μg/g dry seed weight. We also established a one‐step purification protocol, achieving a recovery of 74% and a purity of 80%, which potentially could be developed into a larger‐scale process to facilitate inexpensive downstream processing. OSGRFT bound to HIV glycans with similar efficiency to GRFT produced in Escherichia coli. Whole‐cell assays using purified OSGRFT and infectivity assays using crude extracts of transgenic rice endosperm confirmed that both crude and pure OSGRFT showed potent activity against HIV and the crude extracts were not toxic towards human cell lines, suggesting they could be administered as a microbicide with only minimal processing. A freedom‐to‐operate analysis confirmed that GRFT produced in rice is suitable for commercial development, and an economic evaluation suggested that 1.8 kg/ha of pure GRFT could be produced from rice seeds. Our data therefore indicate that rice could be developed as an inexpensive production platform for GRFT as a microbicide component. 相似文献
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Regulating retrotransposon activity through the use of alternative transcription start sites 下载免费PDF全文
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Redrawing the map: mtDNA provides new insight into the distribution and diversity of short‐finned pilot whales in the Pacific Ocean 下载免费PDF全文
Amy M. Van Cise Phillip A. Morin Robin W. Baird Aimee R. Lang Kelly M. Robertson Susan J. Chivers Robert L. Brownell Jr. Karen K. Martien 《Marine Mammal Science》2016,32(4):1177-1199
Correlations between morphological and genetic data provide evidence to delineate species or evolutionarily significant units, which then become the units to conserve in management plans. Here, we examine the distribution and genetic differentiation of two morphotypes of short‐finned pilot whale (Globicephala macrorhynchus) in the Pacific Ocean. Mitochondrial control region sequences from 333 samples were combined with 152 previously published sequences to describe genetic variability globally and population structure in the Pacific. Although genetic variability is low, we found strong differentiation at both broad and local levels across the Pacific. Based on genetics, two types are distributed throughout the Pacific, one predominantly in the eastern Pacific and the other in the western and central Pacific. In the eastern Pacific Ocean, no correlation was found between distribution and sea surface temperature. The two types have broad latitudinal ranges, suggesting their distributions are likely driven by more complex factors, such as prey distribution, rather than sea surface temperature. 相似文献
199.
Michael A. Hardigan Emily Crisovan John P. Hamilton Jeongwoon Kim Parker Laimbeer Courtney P. Leisner Norma C. Manrique-Carpintero Linsey Newton Gina M. Pham Brieanne Vaillancourt Xueming Yang Zixian Zeng David S. Douches Jiming Jiang Richard E. Veilleux C. Robin Buell 《The Plant cell》2016,28(2):388-405
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