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81.
A coarse-grained model for simulation of interfacial phenomena in aqueous systems has been developed. The model captures the hydrophobic effect by only considering the structure and cohesiveness of water. Monte Carlo (MC) simulations of water-oil mixtures show that low concentrations of oil are solvated with little perturbation of the hydrogen bonding network structure of the water, while high concentrations of oil are excluded altogether. Analysis of the water structure in the simulations indicates that the water molecules maintain close to four coordination in the presence of solutes and the distribution of bond angles is not markedly affected by the presence of solutes. MC simulations of an alkane oligomer in water and a poly(ethylene oxide) (PEO) oligomer in water indicate that the chains are quite flexible and also do not perturb the network structure of the water phase.  相似文献   
82.
《Anthrozo?s》2013,26(4):300-322
Abstract

Two hundred and ten owners or carers completed a specially modified version of the NEO-Personality Inventory-Five Factor Inventory (NEO-PI-FFI, a well established personality questionnaire for humans) for their chosen horse. Three and five-factor Principal Components Analysis (PCA) solutions are reported and compared with published studies on the factor structure of human personality. Participants were asked how confident they were in using each of the different Big Five scales in describing their horse: neuroticism and extraversion were rated with most confidence and openness to experience with least confidence. Taking both our own factors above and the NEO scales, some comparisons between the working roles of the horse were significant; for example, horses used for teaching were less extraverted than show jumpers. Sophistication of working role also related to personality; for example, international horses were less extraverted than novices. We conclude that the study provides some evidence for cross-species similarity in the structure of personality.  相似文献   
83.
Mutualisms between invasive ants and honeydew‐producing insects can have widespread negative effects on natural ecosystems. This is becoming an increasingly serious problem worldwide, causing certain ecosystems to change radically. Management of these abundant and influential mutualistic species is essential if the host ecosystem is to recover to its former non‐invaded status. This negative effect is particularly prevalent on some tropical islands, including Cousine Island, Seychelles. On this island, the invasive ant Pheidole megacephala has caused serious indirect damage to the threatened native Pisonia grandis trees via a mutualism with an invasive scale insect, Pulvinaria urbicola. We aimed to suppress the ant, thereby decoupling the mutualism and enabling recovery of the Pisonia trees. We treated all areas where ant pressure was high with a selective formicidal bait, which was deployed in custom‐made bait stations designed to avoid risk of treatment to endemic fauna. In the treated area, ant foraging activity was reduced by 93 percent and was followed by a 100 percent reduction in scale insect density. Abundance of endemic herbivorous insects and herbivorous activity increased significantly, however, after the decline in mutualistic species densities. Despite the native herbivore increase, there was considerable overall improvement in Pisonia shoot condition and an observed increase in foliage density. Our results demonstrate the benefit of strategic management of highly mutualistic alien species to the native Pisonia trees. It also supports the idea that area‐wide suppression is a feasible alternative to eradication for achieving positive conservation management at the level of the forest ecosystem.  相似文献   
84.
Early Late Miocene coral assemblages from five outcrops of Gavdos Island, Southern Greece, are investigated with respect to their palaeoecological implications. Small patch reefs with Porites assemblage are a common feature of the low-diversity coral occurrences. The determined hermatypic colonies indicate a nearshore palaeoecosystem prevailing in a tropical to subtropical coastal sea at depths ranging from 5 to 50 m with an average temperature of 22–26 °C. Microfacially, the studied Scleractinian patch reefs are represented by Coral Framestones-Floatstones. The reefal facies has been affected by syndepositional processes (boring activities-micritization), as well as by post-depositional diagenesis in the meteoric realm (dissolution, cementation and intense pedogenesis). The palaeoecological and sedimentological analysis indicates a restricted to open-marine inner platform setting of moderate to high energy, possibly of ramp-type (inner-mid ramp). Coral reef growth took place mainly during stages of accommodation (i.e., transgressive episode, cycle 3.1 of Vail curve) and of relatively low siliciclastic input.  相似文献   
85.
Islands are hotspots of biodiversity, with a disproportionately high fraction of endemic lineages, often of ancient origin. Nevertheless, intra‐island phylogeographies are surprisingly scarce, leading to a scanty knowledge about the microevolutionary processes induced on island populations by Plio‐Pleistocene climatic oscillations, and the manner in which these processes contributed to shape their current genetic diversity. We investigated the phylogeography, historical demography and species distribution models of the Corsican endemic newt Euproctus montanus (north‐western Mediterranean). As for many island endemics, the continuous distribution of E. montanus throughout its range has hitherto been considered as evidence for a single large population, a belief that also guided the species' categorization for conservation purposes. Instead, we found a geographic mosaic of ancient evolutionary lineages, with five main clades of likely Pliocene origin (2.6–5.8 My), all but one restricted to northern Corsica. Moreover, the copresence between main lineages in the same population was limited to a single case. As also suggested by growing literature on intra‐island phylogeographic variation, it seems that the extensive use of simplifying assumption on the population structure and historical demography of island populations—both in theoretical and applicative studies—should be carefully reconsidered, a claim that is well exemplified by the case presented here.  相似文献   
86.
记述了采自萨哈林岛1新种,Alopecosa mikhailovi sp.nov.,2♂♂,新种与solivaga种团近似.  相似文献   
87.
Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long‐term persistence of these species following local extinction. This study explored population connectivity in the ecologically‐specialized endemic three‐striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self‐replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self‐replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self‐replenishment (95%), and low contemporary abundance.  相似文献   
88.
目的:探讨不同方式胆囊切除术中抗菌治理的效果.方法:选择我院收治的50例接受胆囊切除术的患者,分别行腹腔镜胆囊切除(LC)和开腹胆囊切除(OC),每组25例,比较两组抗生素使用情况、手术情况及临床疗效.结果:观察组手术时间、术中出血量、肠功能恢复时间及住院天数明显少于对照组,差异有统计学意义(P<0.05).观察组在术前及术后使用抗生素的例数及使用时间均少于对照组,根据抗菌药物的使用率,排在前五位的分别是:硝基咪唑类,氟喹诺酮类,青霉素类,头孢菌素类和氨基糖甙类.结论:根据病情发展,确定抗菌药物的使用疗程,尽量减少抗菌药物的使用时间,减少患者的住院时间.  相似文献   
89.
目的:探讨超声在围绝经期妇科疾病诊断中的作用,为临床诊断提供依据.方法:选取2012年2月至2012年8月间于我院接受诊断和治疗的处于围绝经期的阴道不规则出血患者128例,观察超声诊断与病理学诊断的差异,分析超声诊断的作用.结果:超声诊断与病理学检查结果的总符合率为95.31%,内膜良性病变类型与内膜癌和癌前病变类型的平均内膜厚度均明显高于内膜生理变化类型(P<0.05),子宫内膜厚度≥10mm的发生内膜良性病变或内膜癌及癌前病变的64例(66.67%),厚度<10 mm的患者发生内膜良性病变或内膜癌及癌前病变10例(31.25%),差异有统计学意义(P<0.05).结论:超声在围绝经期妇科疾病诊断中的作用显著,值得在临床上推广应用.  相似文献   
90.
Granite‐derived soils are widespread in the farmland of Korea in general. In contrast, Jeju Island has mainly volcanic ash soils. Soils and weather condition in Jeju Island created a unique agricultural system. We identified the features of ground‐dwelling insects in farmlands of Jeju Island. This study was conducted in four areas (Samdal‐ri and Susan‐ri in Seogwipo city, and Dongmyeong‐ri and Suwon‐ri in Jeju city) in Jeju Island, Korea. Field surveys were carried out twice in summer (June) and autumn (September) in 2013. Ground‐dwelling insects were sampled quantitatively by using pitfall traps. As a result, in total 3322 individuals, 137 species, 48 families and 8 orders were investigated in farmlands of Jeju Island. Especially, members of Coleoptera and Hymenoptera accounted for a large proportion of ground‐dwelling insect communities. The numbers of species and individuals for major taxonomic groups showed significant regional and seasonal differences. This study implied that the seasonal and regional differences of ground‐dwelling insect communities were affected by surrounding land use patterns, life history patterns of each taxonomic group and farmland management.  相似文献   
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