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1.
Matthew W. Mitchell Sabrina Locatelli Ekwoge E. Abwe Lora Ghobrial Mary Katherine Gonder 《International journal of primatology》2018,39(4):581-601
Complex ecological pressures affect the social dynamics of many primate species, but it is unclear how they affect primate speciation. Molecular tools are often used to answer questions about the evolutionary histories and social systems of primates. Mitochondrial DNA (mtDNA), in particular, is frequently used to answer many of these questions, but because it is passed from mothers to offspring it reveals only the histories of females. In many species, including chimpanzees, females generally disperse from their natal groups while males are philopatric, and thus differences in dispersal patterns likely leave different signatures in the genome. We previously analyzed samples from 187 unrelated male and female chimpanzees in Nigeria and Cameroon using 21 autosomal microsatellites and mtDNA sequences. Here, we examine the contributions of males and females in shaping the genetic history of these chimpanzees by genotyping a subset of 56 males at 12 Y-chromosome microsatellites. We found that Y-chromosome population structure differed from the results of analysis of mtDNA haplotypes. The results also revealed that males in rainforest habitats (Guinean and Congolian rainforests) are more closely related to one another than those inhabiting the savanna-woodland mosaic ecotone in central Cameroon. In contrast, the pattern of female relatedness did not differ across habitats. We hypothesize that these differences in population structure and patterns of relatedness among males in different habitat types may be due to differences in the community dynamics of chimpanzees in the ecotone vs. rainforests, and that these factors contribute to making Cameroon an engine of diversification for chimpanzees. Broadly, these results demonstrate the importance of habitat variation in shaping social systems, population genetics, and primate speciation. 相似文献
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Sabrina Nickel Farnusch Kaschani Tom Colby Renier A.L. van der Hoorn Markus Kaiser 《Bioorganic & medicinal chemistry》2012,20(2):601-606
Activity-based protein profiling represents a powerful methodology to probe the activity state of enzymes under various physiological conditions. Here we present the development of a para-nitrophenol phosphonate activity-based probe with structural similarities to the potent agrochemical paraoxon. We demonstrate that this probes labels distinct serine hydrolases with the carboxylesterase CXE12 as the predominant target in Arabidopsis thaliana. The designed probe features a distinct labeling pattern and therefore represents a promising chemical tool to investigate physiological roles of selected serine hydrolases such as CXE12 in plant biology. 相似文献
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Fiddler crabs (Uca spp., Decapoda: Ocypodidae) are commonly found forming large aggregations in intertidal zones, where they perform rhythmic waving displays with their greatly enlarged claws. While performing these displays, fiddler crabs often synchronize their behavior with neighboring males, forming the only known synchronized visual courtship displays involving reflected light and moving body parts. Despite being one of the most conspicuous aspects of fiddler crab behavior, little is known about the mechanisms underlying synchronization of male displays. In this study we develop a spatially explicit model of fiddler crab waving displays using coupled logistic map equations. We explored two alternative models in which males either direct their attention at random angles or preferentially toward neighbors. Our results indicate that synchronization is possible over a fairly large region of parameter space. Moreover, our model was capable of generating local synchronization neighborhoods, as commonly observed in fiddler crabs under natural conditions. 相似文献
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Sustainability indicator programs in developing countries are the poor cousin of ecological indicator research. While an enormous number of indicators for the monitoring of sustainable development exists, few meta-evaluations on these measurements have been conducted in developing countries. Yet, researchers developing new programs face the question: how shall we design our monitoring instrument to respond to the local challenges.By presenting a qualitative meta-performance evaluation of seven sustainability indicator programs on the municipal level in developing countries of Asia, we identify crucial success factors in this contribution. The research draws on 41 expert interviews in Indonesia, Thailand, China, and India, as well as on program-related documents. In the presented case studies, local contexts are intended to be diverse: obtained results should map success factors in different settings. A context-related list of good-practice factors is derived from the interview material via a Qualitative Content Analysis and assessed against the data.We identify crucial strengths and weaknesses of sustainability indicator programs in six dimensions and link the success factors to their contexts. The results include innovative approaches to indicator types, data collection and data quality control, and a correlation between the anchoring of programs in approved development plans and long-term implementation. The results can provide valuable guidance to users of existing sustainability indicator programs and planners of new programs. 相似文献
7.
L-phenylisopropyladenosine (L-PIA) diminishes halothane anesthetic requirements and decreases noradrenergic neurotransmission in rats 总被引:1,自引:0,他引:1
The effect of L-phenylisopropyladenosine (L-PIA), the A1 adenosine agonist, on the depth of anesthesia was investigated in halothane-anesthetized rats. L-PIA treatment reduced the minimum anesthetic concentration (MAC) of halothane that prevented 50% of animals from moving in response to a painful stimulus by 49%. MAC experiments performed with L-PIA given in conjunction with A1 adenosine receptor antagonists which either permeate the blood-brain barrier (8-phenyltheophylline [8-PT] or do not (8-sulphophenyltheophylline [8-So-PT]) indicate that central mechanisms are involved. Noradrenergic neurotransmission was diminished following L-PIA administration in halothane-anesthetized rats in all brain regions. These data suggest that acute L-PIA treatment decreases central noradrenergic neurotransmission and may represent the mechanism for the decrease in halothane dose to achieve an anesthetic endpoint anesthetic response to halothane. 相似文献
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N. Y. Yalcin-Mendia M. Ipek H. Kacan S. Curuk N. Sari S. Cetiner V. Gaba 《Journal of plant biochemistry and biotechnology.》2003,12(2):147-150
The optimization of regeneration protocol for different genotypes increases the yield in transformation studies. Cotyledon explants of watermelon [Citrullus lanatus (Thunb) Matsum & Nakai] cv Crimson Sweet were cultured on MS medium containing combinations of benzyl adenine (BA) (0, 5, 10, 20 µM) and indole-3-acetic acid (IAA) (0, 0.5, 5 µM). Maximum shoot growth and subsequent rooting from explants on regeneration medium were obtained from the media containing 10 µM BA + 0.5 µM IAA and 20 µM BA (75 and 78%) by direct organogenesis, respectively. Histological analysis showed that cell division was observed in the epidermal and subepidermal layers. Protuberant structures were observed in tissues between 7 and 12 days in culture. Meristematic structures were observed after 12days in culture which later developed into buds. 相似文献
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