951 resultados para Two-way trade


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O aumento da obesidade materna pode refletir em efeitos deletérios na prole adulta, manifestos diferentemente de acordo com o gênero do indivíduo. Este trabalho teve como objetivo verificar a hipótese de que a obesidade materna provoca alterações metabólicas, na estrutura do tecido adiposo e hepático e mudanças de perfil inflamatório nas proles adultas de machos e fêmeas. Fêmeas C57BL/ 6 receberam dieta padrão (SC, 17% da energia proveniente do lipídeo) ou dieta hiperlipídica (HF; 49% da energia proveniente do lipídeo) durante oito semanas pré-gestacionais até a lactação. Após o desmame, os filhotes foram divididos nos grupos: SCM (machos), SCF (fêmeas), HFM (machos) e HFF (fêmeas). As características metabólicas foram avaliadas pela massa corporal (MC), glicemia de jejum, área sob a curva no teste oral de tolerância a glicose; concentrações de triglicerídes (TG) hepáticos e estimativa da esteatose hepática; análise plasmática de insulina, colesterol total (CT), triglicerídes (TG) e adipocinas; distribuição e análise morfológica do tecido adiposo e estado pró-inflamatório dos filhotes. Diferenças entre os grupos foram analisadas pelo Teste T não pareado (dados entre progenitoras e pares de grupos nas proles); one-way ANOVA com pós-teste de Tukey (para proles) e two-way ANOVA (efeito da dieta materna e gênero). O nível de significância adotado foi de P≤0,05. Progenitoras HF tiveram maior MC (+20%), glicemia elevada (+22%) e intolerância à glicose em comparação ao grupo SC. A partir da quarta semana, a MC mostrou-se maior nas proles HF, em ambos os gêneros, quando comparados às proles SC. Na 12 semana, a MC foi 20% maior no grupo HF macho e 30% maior no grupo HF fêmea do que seus controles (p<0,0001, ambos os gêneros). Intolerância à glicose foi observada em machos e fêmeas HF em relação aos seus contrapares SC (+20%, p<0,05). Proles HF demonstraram hepatomegalia com maior acúmulo de TG hepático, resultando em maior percentual de esteatose em machos (27%) e fêmeas HF (25%). Proles HF apresentaram incremento na adiposidade (+20%) e nos níveis de CT e TG do que seus congêneres SC. Níveis plasmáticos de leptina e insulina foram maiores, enquanto houve diminuição da adiponectina no grupo HF macho em relação ao grupo SC macho. Hipertrofia de adipócitos foi observada nas proles HF. TNF-alfa, IL-6 e leptina foram mais expressos em proles HF, porém diminuição na expressão de adiponectina foi evidenciada nas proles geradas por mães obesas. A luz do exposto, a dieta HF administrada em mães antes e durante períodos de gestação e lactação leva à obesidade materna que tem consequências na prole, tais como remodelamento do tecido adiposo, juntamente com alterações bioquímicas e metabólicas dos adipócitos, intensificando o estado pró-inflamatório da prole, em ambos os gêneros, na idade adulta.

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Based on shape memory effect of the sputtered thin film shape memory alloys, different types of micromirror structures were designed and fabricated for optical sensing application. Using surface micromachining, TiNi membrane mirror structure has been fabricated, which can be actuated based on intrinsic two-way shape memory effect of the free-standing TiNi film. Using bulk micromachining, TiNi/Si and TiNi/Si 3N 4microcantilever mirror structures were fabricated. © 2007 IOP Publishing Ltd.

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A study of two factors with two-way classification shows that the main effect of newspaper subscription on the adoption of improved practices in fish curing is significant. The effect of radio ownership appears to be masked by newspaper subscription. The interaction between the two factors was not significant. The study confirms the importance of mass media in adoption.

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The distribution of fish caught by experimental gill nets has been found to be in the Poisson or Negative binomial form. Using this information, application of Chi-square test as suggested by Mood et al. (1974) has been illustrated, for comparing the efficiencies of gill nets. This test provides an alternative to Anova F-test especially in the context of significance of non-additivity for the two-way model. Based on the present work and the findings by Nair (1982) and Nair & Alagaraja (1982, 1984) an outline approach for statistical comparison of the efficiencies of fishing gear is presented.

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An infinite series of twofold, two-way weavings of the cube, corresponding to 'wrappings', or double covers of the cube, is described with the aid of the two-parameter Goldberg- Coxeter construction. The strands of all such wrappings correspond to the central circuits (CCs) of octahedrites (four-regular polyhedral graphs with square and triangular faces), which for the cube necessarily have octahedral symmetry. Removing the symmetry constraint leads to wrappings of other eight-vertex convex polyhedra. Moreover, wrappings of convex polyhedra with fewer vertices can be generated by generalizing from octahedrites to i-hedrites, which additionally include digonal faces. When the strands of a wrapping correspond to the CCs of a four-regular graph that includes faces of size greater than 4, non-convex 'crinkled' wrappings are generated. The various generalizations have implications for activities as diverse as the construction of woven-closed baskets and the manufacture of advanced composite components of complex geometry. © 2012 The Royal Society.

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The assemblage of oligochaetes in the Liangzi Lake District, located in middle reaches of the Changjiang River, was studied from May to August, 2001. To establish species composition, richness, and abundance and detect the influence of environmental variables on oligochaete distributional patterns, 45 localities were sampled. All total, 20 species belonging to the families Naididae (eight species), Tubificidae (11 species), and Lumbriculidae (one species) were found. Branchiura sowerbyi, Tubifex sp. 1, and Aulodrilus pluriseta were the dominant species and contributed nearly 70% of the total abundance. The 45 sampling sites were separated into three groups based on composition and relative abundance of benthic oligochaete communities using two-way indictor species analysis associated with detrended correspondence analysis. Canonical correspondence analysis indicated that two plant variables (total plant cover and total submersed macrophyte biomass) were strongly correlated with the faunal gradient (p < 0.05). Other predicator variables were water depth and total nitrogen.

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Surveys of macroinvertebrates were carried out in the Xiangxi River system during July of 2001. Among the 121 taxa collected, Ephemeroptera, Trichoptera, and Diptera dominated (41.7, 26.0, and 24.5% of the total relative abundance, respectively). Two-way indictor species analysis and detrended correspondence analysis divided the 49 sites into four groups based on species composition and relative abundance. Canonical correspondence analysis indicated that elevation, SiO2, pH, conductivity, hardness, and NO2-N were significant environmental factors affecting the distribution of macroinvertebrates.

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Ecological survey of macrozoobenthos assemblages was carried out at 32 sites in the East Dongting Nature Reserve, located in the northern region of the East Dongting Lake in the middle basin of the Yangtze River, China. All total 51 taxa including 18 oligochaetes, 15 mollusks, 14 insects and four other animals were recorded. Mollusks composed the dominant group and accounted for more than 70% of the total abundance. Assemblages were composed mainly of scrapers (66.7%) and collector-gatherers (nearly 20%), and to a lesser extent collector-filterers (roughly 12%), predators (ca. 7%), and shredders (ca. 6%). Two-way indicator species analysis, detrended correspondence, and canonical correspondence analysis (CCA) were employed to identify the relationships between macrozoobenthos assemblages and environmental variables. Thirty-two sites were separated into four site groups based on composition and relative abundance of benthic macroinvertebrates. CCA detected that water depth, pH, conductivity, SiO2, total nitrogen, total phosphorus, alkalinity, hardness, and Ca2+, were significant environmental factors influencing the pattern of macozoobenthos. In this minimal subset, water depth, pH, alkalinity and hardness were the most influential variables.

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The spatial pattern of epilithic algae in the Xiangxi River system was studied in relation to several environmental factors by two-way indictor species analysis (TWINSPAN), detrended correspondence analysis (DCA), and canonical correspondence analysis (CCA). Eighty-nine taxa including diatoms, green algae, and blue-green algae were observed. Diatoms were dominant, and Cocconeis placentula, Cymbella minuta, Diatoma vulgare, and Gomphonema angustatum appeared in most of sampling sites. By TWINSPAN and DCA, thirty-one sites were divided into three groups based on composition and relative richness of benthic algae. CCA indicated that SiO2, pH, total phosphorus, Ca2+, velocity, elevation, and Cl- were significant environmental factors affecting the distribution of algae communities. In this minimal subset, SiO2 and pH were the most influential variables.

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Echolocation click events of a free-ranging juvenile and an adult finless porpoise (Neophocaena phocaenoides) were recorded with an acoustic data logger. Additionally, dive depth and swim speed of the juvenile were recorded with a behavior data logger. Echoes of echolocation signals from the water surface were clearly detected in shallow dives approximately less than 2 m. The delay time between a surface echo and a direct signal corresponded with the two-way transmission time for the animal's depth, indicating that the signals originated from the animal wearing the data loggers. The finless porpoises produced echolocation signals frequently and were thought to be able to detect their depth by listening to echoes from the water surface. (C) 2000 Acoustical Society of America. [S0001-4966(00)01609-X].

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The interclick intervals of captive dolphins are known to be longer than the two-way transit time between the dolphin and a target. In the present study, the interclick intervals of free-ranging baiji, finless porpoises, and bottlenose dolphins in the wild and in captivity were compared. The click intervals in open waters ranged up to 100-200 ms, whereas the click intervals in captivity were in the order of 4-28 ms. Echolocation of free-ranging dolphins appears to adapt to various distance in navigation or ranging, sometimes up to 140 m. Additionally, the difference of waveform characteristics of clicks between species was recognized in the frequency of maximum energy and the click duration. (C) 1998 Acoustical Society of America. [S0001-4966(98)06609-0].

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随着SOA和业务流程管理BPM技术日益成熟,基于业务流程的开发得到越来越广泛的应用。BPMN是由国际标准组织BPMI所制定的业务流程描述语言,制定了标准化的图形符号用于流程的设计和交流。WS-BPEL是面向服务计算中服务复合层重要的技术规范,WS-BPEL支持通过组合分布异构的服务形成复杂的业务流程。BPMN和BPEL模型之间存在差异,跨越两者之间的鸿沟实现无缝转换是当前服务计算中的关键问题之一。现有的BPMN到BPEL转换方法对用户建模限制太大,并且转换后的BPEL不能直接部署和运行,自动化程度不高。现有BPEL到BPMN转换方法缺少对复杂BPEL结构的转换。 针对这些问题,论文设计了一套双向模型转换方法。首先分析了现有BPMN到BPEL的转换方法。然后根据分析结果对已有的BPMN到BPEL转换方法进行扩展,并着重解决了路由OR和并发多实例Multi-instance的语义分析和转换这一难点问题,减少了用户建模时的限制,转换得到的可直接执行的BPEL,提高了自动化程度。在此基础上,设计了BPEL到BPMN的转换方法,采取自上而下的扁平化策略来将嵌套块结构的BPEL控制流转换成为平整无层次的流程图结构,其中分析了Link设置不同条件时的语义并分别转换到对应的BPMN结构,解决了复杂BPEL结构的转换。 最后,我们在流程设计平台OnceBPD(Once Business Process Designer)实现了双向转换功能,能够将BPMN模型转换为BPEL模型,得到的BPEL文件可以部署和运行在OnceBPEL流程执行引擎。还可以将BPEL模型装换为BPMN模型,并应用于OnceBPEL引擎监控信息的可视化,实现了在OnceBPD中直观、形象的显示流程监控。

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采用TWINSPAN分类法对黄土丘陵沟壑区吴起县双树沟流域30个自然恢复草地植被进行分类,并对分类后各植被群落特征和地上生物量进行统计分析。结果表明:在自然恢复条件下,随着退耕年限的不断增加,退耕地植被自然恢复依次经历了猪毛蒿群落—赖草+长芒草群落—赖草+铁杆蒿群落—铁杆蒿群落—铁杆蒿+茭蒿群落5个发展阶段,地带性植被类型铁杆蒿+茭蒿群落在研究区内开始出现,并且已经占有一定优势;随着退耕地植被自然恢复的不断进行,Margalef等丰富度指数以及Shannon-wiener等多样性指数、Pielou等物种均匀度指数和地上生物量都呈现出先减小后增大的发展趋势;在植被自然恢复的稳定阶段,虽然物种丰富度指数和物种多样性指数有一定的增加,但是相对恢复初期来讲还是有所下降,并且有达到与初期相当水平的趋势;物种丰富度指数均在第1恢复阶段最大,而均匀度指数Jsw以及Shannon-wiener指数在第5恢复阶段最高。随着退耕地植被自然恢复的不断进行,植被群落总盖度随着退耕年限的延长而不断增大。

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提出一个在线双向适应的笔手势界面框架,该框架针对传统笔手势界面中静态手势识别器不能支持用户的个性化输入以及用户在笔手势界面中面临的手势记忆问题,提出了在线双向适应的策略:一方面系统能够适应用户(系统可以在线支持用户的个性化输入);另一方面用户可以学习系统(用户可以学习系统提供的某些笔手势).该框架包括5个部分:(1)双向适应笔手势输入解释模型;(2)双向适应笔手势输入解释流程;(3)上下文优先级定义;(4)纠错和模糊消解界面;(5)在线笔手势查询帮助系统.在该框架的指导下作者开发了一个原型系统并进行了对比实验评估.结果表明该框架在可用性上具有较大的优势.

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已有的研究表明,眶额叶在解剖上与现在已知的药物滥用相关的脑区是紧密联系在一起的。例如,眶额叶在药物滥用和强迫性重复行为中起作用,且随着脑成像技术的应用,越来越多的证据表明眶额叶参与了药物滥用。但是我们并不了解在阿片给药和戒断期间眶额叶脑区活动是如何变化的。因此,我们在实验中采用了Mn2+增强的核磁共振成像(Manganese-enhanced magnetic resonance imaging,MEMRI,4.7T)技术和脑电(EEG)记录的方法,以研究大鼠眶额叶在给与阿片类药物(盐酸吗啡)以及戒断过程中的动态变化。 MEMRI是一种近年才发展起来的新型技术。研究表明,Mn2+是Ca2+的类似物,可以通过Ca2+通道进入兴奋性的神经元里面并结合到胞内的蛋白质和核酸上的Ca2+和Mg2+结合位点上 (MILDVAN and COHN, 1963; EISINGER et al., 1965)。另外,Mn2+的顺磁性也为它成为核磁共振成像的造影剂提供了前提条件。可是成功应用MEMRI的前提就是要在适当的时间把合适剂量的Mn2+传递到靶点上。因此,Mn2+在注射到靶点后,是否能够在有效的时间内反映大脑活动的变化就成为一个非常重要并且在技术上较为棘手的问题。在给实验大鼠脑区微量注射Mn2+(80mMol/L,200nl)的同时,通过微量注射兴奋性神经递质谷氨酸(Glu 0.5mM/L)或抑制性递质γ-aminobutyric acid(GABA 0.5M/L)以改变靶点神经元兴奋性的方法,检测Mn2+能否反映脑区的活动变化。另外,我们随机选取实验动物,分别在注射Mn2+ 3小时、5小时和8小时后对三组大鼠(n=5)进行10%福尔马林灌流,并且通过观察大鼠眶额叶脑区Mn2+强度的变化来研究最佳的灌流时间。我们的实验结果表明,Mn2++Glu组的右侧脑区/左侧脑区的Mn2+亮度比Mn2+空白对照组增加了20%(p=0.016, student t-test, *p <0.05),也远大于Mn2++GABA组(p=0.047, *p<0.05)。结果表明,当神经元被兴奋的时候,较多的Mn2+可以通过Ca2+通道进入兴奋的神经元内,使得Mn2+的成像亮度增加。由于Mn2+成像亮度的增加可以反映神经元的兴奋活动,因此可以显示出靶点区的脑活动。另外,在研究灌流时间对Mn2+亮度影响的实验中发现,注射Mn2+ 5小时后灌流得到的信噪比分别比注射Mn2+3小时(p=0.055)和8小时(p=0.004,*p<0.05)高出24%和32%。总之,我们采用微量注射Mn2+(80mM/L,200nl)后5小时用10%福尔马林心脏灌流的方法获得了较好的结果。另外在试验中我们首先观测了大鼠吗啡戒断后的行为学指标和检测大鼠戒断后条件化位置偏好的程度。实验结果表明大鼠可以建立非常明显的条件化位置偏好,但在湿狗抖等行为学指标上无明显症状。这说明大鼠对于吗啡(10mg/kg, 一天两次,持续12天)形成了明显的心理依赖而无明显的生理依赖。此外,MEMRI的结果表明,在吗啡给药的第1天和第6天,大鼠眶额叶的Mn2+强度与空白对照组相比有显著的降低( one-way ANOVA, Post Hoc Dunnett’s C Tests), F (6,28)=7.242, P<0.001);而在戒断第3天又恢复到正常水平,在戒断第5天和第7天Mn2+强度跟空白对照组相比没有显著性差别(one-way ANOVA, *p<0.05)。脑电(EEG)的结果表明,急性吗啡诱导的gamma波段的EEG显著降低(Two-way ANOVA, F(1,10)=13.626,p=0.006)。然而在戒断第1天gamma波段的EEG与空白对照组相比是增加的。在戒断第3天和戒断第5天,gamma波段的EEG与空白对照组相比也有显著性增强。以上研究结果表明:大鼠眶额叶脑区的动态变化与整个吗啡给药和戒断过程是密切相关的;此外,MEMRI在探讨药物滥用以及成瘾等机制上有很大的应用前景。