Foraging Ecology of the Tropical Giant Hunting Ant Dinoponera australis (Hymenoptera: Formicidae)—Evaluating Mechanisms for High Abundance

A central goal of ecology is to understand the mechanisms behind variation in the abundance of species. Food web theory predicts higher biomass for animals at lower trophic levels. However, some high trophic level species may reach great abundance via highly efficient foraging behaviors. We evaluated ecological and behavioral traits of the giant tropical ant Dinoponera australis related to these mechanisms. We determined its distribution and abundance, documented its foraging behavior, and measured its trophic position in a population at P.N. Iguazú, Argentina. We report that D. australis colonies are overdispersed, and the species reaches a wet biomass of more than 2.5 kg/ha at this site. Dinoponera australis foraging behavior is characterized by route fidelity of individual workers, with different individuals specializing on different areas around the nest. Finally, stable isotopic evidence and direct observation suggest these ants are among the top predators in this terrestrial invertebrate community. We interpret our findings in the context of how the behavior of an abundant top predator creates an exception to the usual trade‐off between biomass and trophic level. Together these data provide insight into the biology of one of the world's largest ants and why they may be able to attain such high densities where they occur.     

消化道传播病毒性肝炎研究进展

病毒性肝炎是由多种不同肝炎病毒引起的,以肝脏损害为主要表现,具有广泛流行性和严重传染性的一类疾病,严重危害人类健康,是我国目前重大的公共卫生问题之一。迄今鉴定出的具有明确致病性的肝炎病毒主要是甲型肝炎病毒(HAV)、乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)、丁型肝炎病毒(HDV)和戊型肝炎病毒(HEV),分别引起甲、乙、丙、丁、戊型肝炎。病毒性肝炎按传播途径的不同可以分为两类,一类是经肠道外传播的病毒性肝炎,包括乙、丙、丁型肝炎;另一类是经肠道(即消化道)传播的肝炎病毒,包括甲肝和戊肝,其发病有季节性,可呈暴发流行。本文旨在对经消化道传播的病毒型肝炎(甲肝、戊肝)的病原学、流行病学特征及其影响因素、控制和预防作一综述,以期对其流行和科学防控研究提供参考。     

Alternate method for endocardial pacemaker lead implantation: A hybrid mini-thoracotomy approach

Although the conventional methods for endo-cardial pacemaker lead implantation via subclavian or cephalic or axillary vein routes is common, but sometimes due to anatomical variations it is not feasible to access these veins Emergence of newer techniques are useful for lead implantation. This case report focuses on a hybrid approach of combined mini-thoracotomy for endocardial pacemaker lead implantation. This fluoroscopy guided minimal thoracotomy approach with endocardial MRI compatible lead placement had the benefits of simple procedural, minimal hospital stay, low early complication rates and economically viable to the patient.     

苏州怡园山水游观体验解析：以光绪三年(1877年)顾文彬所述游线为线索

以园主或设计者所策划的游线来解析一座园林的山水游观体验,将有助于理解这座园林的真实造园意匠及其背后的空间经营目的。以苏州怡园为例,本文在梳理其新近史料的基础上,考证了园主顾文彬于光绪三年（1877年）时所述的怡园游线,并在利用该游线完整解析怡园山水游观体验的过程中,总结指出这一游线本质上是在“快速概览园貌”与“细致品味园景”之间所取得的平衡。而对此的认知,或将促进怡园营造艺术的深入理解。     

海上丝路东海航线之濑户内海区域的景观振兴观察

濑户内海海域作为日本重要的商旅之路、近现代最大的新兴工业聚集地区以及海上丝路东海航线的延展,一直保有重要的文化意义和价值。国内现有研究分散于环境治理、工业布局、艺术活动等方面,但未能揭示该海域发展中社会、环境等因素的整体状况。为研究该海域的固有环境景观变迁问题,对日本社会各界与不同层面导入的濑户内海治理、振兴的研究及实践活动进行了综合考查。结合其历史信息与变迁过程,通过对相关法律法规及课题探讨的梳理,可发现,在统领于广义景观概念下的基础研究、创新研究、细节对策3个方面,对促进该区域的振兴工作有着显著的影响。同时其景观策略具有社会各界广泛参与的特征。     

Conformational frustration in calmodulin–target recognition

Calmodulin (CaM) is a primary calcium (Ca²⁺)‐signaling protein that specifically recognizes and activates highly diverse target proteins. We explored the molecular basis of target recognition of CaM with peptides representing the CaM‐binding domains from two Ca²⁺‐CaM‐dependent kinases, CaMKI and CaMKII, by employing experimentally constrained molecular simulations. Detailed binding route analysis revealed that the two CaM target peptides, although similar in length and net charge, follow distinct routes that lead to a higher binding frustration in the CaM–CaMKII complex than in the CaM–CaMKI complex. We discovered that the molecular origin of the binding frustration is caused by intermolecular contacts formed with the C‐domain of CaM that need to be broken before the formation of intermolecular contacts with the N‐domain of CaM. We argue that the binding frustration is important for determining the kinetics of the recognition process of proteins involving large structural fluctuations. Copyright © 2015 John Wiley & Sons, Ltd.     

Global aerial flyways allow efficient travelling

Birds migrate over vast distances at substantial costs. The highly dynamic nature of the air makes the selection of the best travel route difficult. We investigated to what extent migratory birds may optimise migratory route choice with respect to wind, and if route choice can be subject to natural selection. Following the optimal route, calculated using 21 years of empirical global wind data, reduced median travel time by 26.5% compared to the spatially shortest route. When we used a time‐dependent survival model to quantify the adaptive benefit of choosing a fixed wind‐optimised route, 84.8% of pairs of locations yielded a route with a higher survival than the shortest route. This suggests that birds, even if incapable of predicting wind individually, could adjust their migratory routes at a population level. As a consequence, this may result in the emergence of low‐cost flyways representing a global network of aerial migratory pathways.