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21.
The Neotropical Region harbors high biodiversity and many studies on mammals, reptiles, amphibians and avifauna have investigated the causes for this pattern. However, there is a paucity of such studies that focus on Neotropical insect groups. Synoeca de Saussure, 1852 is a Neotropical swarm-founding social wasp genus with five described species that is broadly and conspicuously distributed throughout the Neotropics. Here, we infer the phylogenetic relationships, diversification times, and historical biogeography of Synoeca species. We also investigate samples of the disjoint populations of S. septentrionalis that occur in both northwestern parts of South America through Central American and the Brazilian Atlantic rainforests. Our results showed that the interspecific relationships for Synoeca could be described as follows: (S. chalibea + S. virginea) + (S. cyanea + (S. septentrionalis/S. surinama)). Notably, samples of S. septentrionalis and S. surinama collected in the Atlantic Forest were interrelated and may be the result of incomplete lineage sorting and/or mitochondrial introgression among them. Our Bayesian divergence dating analysis revealed recent Plio-Pleistocene diversification in Synoeca. Moreover, our biogeographical analysis suggested an Amazonian origin of Synoeca, with three main dispersal events subsequently occurring during the Plio-Pleistocene.  相似文献   
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Background

Effective coordination between organizations, agencies and bodies providing or financing health services in humanitarian crises is required to ensure efficiency of services, avoid duplication, and improve equity. The objective of this review was to assess how, during and after humanitarian crises, different mechanisms and models of coordination between organizations, agencies and bodies providing or financing health services compare in terms of access to health services and health outcomes.

Methods

We registered a protocol for this review in PROSPERO International prospective register of systematic reviews under number PROSPERO2014:CRD42014009267. Eligible studies included randomized and nonrandomized designs, process evaluations and qualitative methods. We electronically searched Medline, PubMed, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL, PsycINFO, and the WHO Global Health Library and websites of relevant organizations. We followed standard systematic review methodology for the selection, data abstraction, and risk of bias assessment. We assessed the quality of evidence using the GRADE approach.

Results

Of 14,309 identified citations from databases and organizations'' websites, we identified four eligible studies. Two studies used mixed-methods, one used quantitative methods, and one used qualitative methods. The available evidence suggests that information coordination between bodies providing health services in humanitarian crises settings may be effective in improving health systems inputs. There is additional evidence suggesting that management/directive coordination such as the cluster model may improve health system inputs in addition to access to health services. None of the included studies assessed coordination through common representation and framework coordination. The evidence was judged to be of very low quality.

Conclusion

This systematic review provides evidence of possible effectiveness of information coordination and management/directive coordination between organizations, agencies and bodies providing or financing health services in humanitarian crises. Our findings can inform the research agenda and highlight the need for improving conduct and reporting of research in this field.  相似文献   
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This study reports the purification and biochemical characterization of a raw starch-digesting α-amylase from Geobacillus thermoleovorans subsp. stromboliensis subsp. nov. (strain PizzoT). The molecular weight was estimated to be 58 kDa by SDS–PAGE. The enzyme was highly active over a wide range of pH from 4.0–10.0. The optimum temperature of the enzyme was 70°C. It showed extreme thermostability in the presence of Ca2+, retaining 50% of its initial activity after 90 h at 70°C. The enzyme efficiently hydrolyzed 20% (w/v) of raw starches, concentration normally used in starch industries. The α-amylase showed an high stability in presence of many organic solvents. In particular the residual activity was of 73% in presence of 15% (v/v) ethyl alcohol, which corresponds to ethanol yield in yeast fermentation process. By analyzing its complete amyA gene sequence (1,542 bp), the enzyme was proposed to be a new α-amylase.  相似文献   
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JCC76 is a derivative of cyclooxygenase-2(COX-2) selective inhibitor nimesulide and exhibits potent anti-breast cancer activity. It selectively induces apoptosis of Her2 positive breast cancer cells. However, the specific molecular targets of JCC76 still remain unclear, which significantly withdraw the further drug development of JCC76. To identify the molecular targets of JCC76, a six carbon linker and biotin conjugated JCC76 probe was designed and synthesized. The anti-proliferation activity of the probe and its analogs was evaluated.  相似文献   
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This contribution describes a new laboratory experience that improves medical students' learning of chronobiology by introducing them to basic chronobiology concepts as well as to methods and statistical analysis tools specific for circadian rhythms. We designed an autorhythmometry laboratory session where students simultaneously played the role of researchers and experimental subjects. During this session, which lasted 24 h, students recorded their own arterial pressure, heart rate, oral temperature, forced expiratory flow, glucose tolerance, muscular strength, reaction time, and sensorimotor coordination at regular intervals and also took the Horne and Ostberg test, after which they analyzed their own data. Furthermore, to gather information from subjects under normal sleep and eating schedules, some students acquired data at home. To guide and help students with their work, a dedicated web page was implemented with scientific references, cosinor analysis software, and other valuable information. All these "raw" data were combined into a single database that students could use to evaluate whatever aspect of the data they seemed fit. A number of suggestions were offered to them as guidance. Students were then instructed to write a scientific article on the subject they had chosen. The experience was highly rewarding for both instructors and students alike. In view of the high level of absenteeism in Spanish universities and the fact that 93% of the students attended the exam and 95% of these passed, the experience was considered a great success.  相似文献   
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Mattar AA  Gribble PL 《Neuron》2005,46(1):153-160
Learning complex motor behaviors like riding a bicycle or swinging a golf club is based on acquiring neural representations of the mechanical requirements of movement (e.g., coordinating muscle forces to control the club). Here we provide evidence that mechanisms matching observation and action facilitate motor learning. Subjects who observed a video depicting another person learning to reach in a novel mechanical environment (imposed by a robot arm) performed better when later tested in the same environment than subjects who observed similar movements but no learning; moreover, subjects who observed learning of a different environment performed worse. We show that this effect is not based on conscious strategies but instead depends on the implicit engagement of neural systems for movement planning and control.  相似文献   
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