946 resultados para Syring, Dick


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Measurements of adult marine fishes on the U.S. west coast are usually made using one of three methods: standard length, fork length, or total length. Each method has advantages and disadvantages. In this paper we attempt to determine whether one method is faster and/or more reliable than the other methods. We found that all three methods were comparable. There was no appreciable difference in the time it took to measure fish using the different methods. Fork length had the most reproducible results; however, it had the highest level of bias between researchers. We therefore suggest that selection of measurement type be based on what other researchers have used for the species under study. The best improvement in measurement reliability probably occurs by adequate training of personnel and not type of measurement used.

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Esta dissertação tem por objetivo o estudo e a realização de procedimentos artísticos singulares que se abrem após o modernismo em diferenças flagrantes, levando a formas contemporâneas de organização do sensível em que as fronteiras entre as especificidades artísticas são cada vez mais diluídas. Conceitos como, dentre outros, o de campo expandido ou campo ampliado, de Rosalind Krauss, de arte inespecífica, de Florencia Garramuño, de intermídia, de Dick Higgins, de quase-cinema, de Hélio Oiticica, de Mistura, de Ricardo Basbaum são de grande importância para a pesquisa, constituindo-se como alvo do trabalho a ser realizado. Por serem constituídos de, ao menos, três mídias distintas (sons, palavras e imagens), que, montadas, se fundem, criando uma obra de múltiplos meios entre as mídias, os vídeos ou os arranjos audiovisuais que apresento nesta dissertação têm como característica central a plurimidialidade

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丁香属Syringa是木樨科Oleaceae中一个中等大小的属,大多数种类花形美丽,具有很高的园林观赏价值。本文以标本检查为主,结合形态学、孢粉学、细胞学和植物地理学几个方面对丁香属进行了分类研究。 一.形态学:丁香属分类的主要性状为:单叶或复叶、圆锥花序的着生位置、花冠管的长短。这些性状的演化趋势为:单叶--羽状深裂--羽状复叶,圆锥花序由顶芽抽生--圆锥花序由侧芽抽生,长花冠管,雄蕊不伸出花冠管--短花冠管,雄蕊伸出花冠管。 二.孢粉学:本文首次对丁香属的花粉形态作了较为全面而系统的研究。所取材料为各组、系、亚系的代表种。孢粉学的研究表明,本属花粉形态一致。均为近球形,极面观3裂圆形,三(拟)孔沟,沟边缘不加厚,外壁分层明显,外层厚于内层,半覆盖层,粗网状纹饰。扫描电镜观察结果表明,本属花粉的表面纹饰可区分为6种类型:1).网眼小,网脊细、较直而使网眼呈多边形,网脊下小柱不明显,2).网眼稍大,网脊细、直,网脊下小柱不明显,3),网眼较大,网脊细、稍弯曲,网脊下小柱可见,4).网眼大,网脊细而弯曲, 网脊下小明显,5).网眼小,网脊细、弯曲而使网眼呈不规则扁长形,6).网眼较大,网脊粗、直,网脊下小柱不明显。顶生花序系Ser. Villosae (Schneid.) Rehd. 以1型为主,侧生花序系Ser. Syringa从2-4型,羽叶丁香系Ser, Pinnatifolia Rehd,为5型,短花冠管组Sect.Ligustrina Rupr.为6型。其变化规律与形态学上的系统演化关系相—致。 三,细胞学:本文对丁香属部分种进行了染色体数目的观察,初步的结果显示,本属的染色体基数为n=23或24,这两种情况在不同的组、系都存在。本属为异源多倍体起源,由陵花目中染色体基数为n=ll和n=12的祖先类群通过杂交形成,并由于染色体组在减数分裂过程中非整倍性变异,而产生n 2或n=24的变化。 四,分类修订及系统位置和演化趋势: 本文在查看了本所标本馆全部丁香属的标本、考证了约22个种的原始描述以及部分模式标本和模式照片的基础上,对该属分类作下列修订:1.将华丁香Syringa protolaciniata、花叶丁香S.x persica、 裂叶丁香S.x laciniata、阿富汗丁香S.afghanica 四个种从欧丁香亚系中移出,置于羽叶丁香系Ser. Pinnatifolia,2.改欧丁香系Set. Vulgares和巧铃花系Ser. Pubescentes为亚系等级,均置于侧生花序系Ser. Syringa中,3.恢复山丁香Syringa potaninii Schneid.、小叶丁香S.micropylla Diels、关东丁香s.patula (Palibin) Nakai、光萼丁香S.juliana Schneid.、朝鲜丁香S.dilatata Nakai,并作为种的等级,毛萼云南丁香S.yunanensis Franch.f.pubicalyx (Jien ex P.Y. Bai) M.C. Chang仍作变种处理。在此基础上,本文将丁香属分为2组3系2亚系: 组1.长花冠管组Sect.l. Syringa:系1.顶生花序系Ser.1.Villosae(Sch- neid.)Rehd.;系2.侧生花序系Ser.2. Syringa,亚系1.欧丁香亚系Subser.1.Syring,亚系2.巧铃花亚系Pubescentes(Schneid.)Rehd.;系3.羽叶丁香系Ser.3. Pinnatifoliae Rehd. 组2.短花冠管组Sect.2. Ligustrina Rupr. 各分类单元的命名,仍沿用已有的名称。 结合各方面的研究成果,表明丁香属是一个十分自然的类群。在木樨科中,本属与女贞属的关系密切,由女贞属裂果女贞组Sect. Sarcocarpion (Franch.)Mansf.衍生而来。属内演化趋势始为长花冠管组的顶生花序系,而后是侧生花序系、羽叶丁香系,短花冠管组为本属中进化程度较高的类群。 五.植物地理学:丁香属为旧世界温带分布型属,分布区连续。约28种5变种9变型。除2种产于欧洲,1种产于阿富汗、巴基斯坦,1种产于朝鲜,1种产于日本外,其余种类均分布于中国。其中,中国西南地区丁香属的种类、原始类型及其在该地区所占比例均显示是丁香属现代分布中心和起源演化中心,并由此沿三条主线向周围扩散。

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Regulation of neuronal gene expression is critical to nervous system development. REST (RE1-silencing transcription factor) regulates neuronal gene expression through interacting with a group of corepressor proteins including REST corepressors (RCOR). Here we show that Xenopus RCOR2 is predominantly expressed in the developing nervous system. Through a yeast two-hybrid screen, we isolated Xenopus ZMYND8 (Zinc finger and MYND domain containing 8) as an XRCOR2 interacting factor. XRCOR2 and XZMYND8 bind each other in co-immunoprecipitation assays and both of them can function as transcriptional repressors. XZMYND8 is co-expressed with XRCOR2 in the nervous system and overexpression of XZMYND8 inhibits neural differentiation in Xenopus embryos. These data reveal a RCOR2/ZMYND8 complex which might be involved in the regulation of neural differentiation. (C) 2010 Elsevier Inc. All rights reserved.

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There are a lot of evidence that show hvdrocarbones cause some defect in reproduction and growth of bivalves. Bivalves are filter-feeder, thus accumulate more hydrocarbones in their tissue. In this study adult pearl producing oysters (Pinctada fucata) are used for all experimens. Samples of oysters, water and sediment from four natural beds; Nakhiloo (clean), Hendurabi (semipolluted), Lavan 1 (semipolluted) and Lavan 2 (polluted) were gatherd for 13 succesive months. Temperature, salinity, pH, oxygen and turbidity were recorded in each sampling. Oysters were kept in laboratory for adapation and then their length (DVM) were measured. Hemolymph samples were collected by insuline syring. Sediments and soft tissues of oysters were dissolved in carbon tetrachloride and when heated to extract oil hydrocarbones. UV, GC and IR were used to assay oil hydrocarbones. Accumulation of hydrocabones in soft tissue were as follows : Kakhiloo

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Early interventions are a preferred method for addressing behavioral problems in high-risk children, but often have only modest effects. Identifying sources of variation in intervention effects can suggest means to improve efficiency. One potential source of such variation is the genome. We conducted a genetic analysis of the Fast Track randomized control trial, a 10-year-long intervention to prevent high-risk kindergarteners from developing adult externalizing problems including substance abuse and antisocial behavior. We tested whether variants of the glucocorticoid receptor gene NR3C1 were associated with differences in response to the Fast Track intervention. We found that in European-American children, a variant of NR3C1 identified by the single-nucleotide polymorphism rs10482672 was associated with increased risk for externalizing psychopathology in control group children and decreased risk for externalizing psychopathology in intervention group children. Variation in NR3C1 measured in this study was not associated with differential intervention response in African-American children. We discuss implications for efforts to prevent externalizing problems in high-risk children and for public policy in the genomic era.

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Los tambos son sistemas productivos muy complejos que dependen básicamente de cuatro pilares considerados como variables: el ambiente, los animales, la alimentación y los operarios. Comederos sin mantenimiento, con barro y estiércol, animales con pobre estado corporal, dietas no balanceadas o deficientes en nutrientes, predisponen a trastornos metabólicos. Personal sin capacitación y/o motivación, no realizará bien las múltiples tareas del tambo. Las vacas lecheras antes y después del parto tienen enormes cambios metabólicos y hormonales y esto es un factor que predispone a las enfermedades peripartales (IP) como: distocias, retención de placenta, edema de ubre, metritis, mastitis, cetosis, acidosis, desplazamiento de abomaso, timpanismo, hipocalcemia puerperal, lesiones podales, etc. ¿Como evaluar las variables?¿que miramos o qué metodología seguimos a campo? Para ello se propone el Índice Predictivo de Enfermedades Peripartales (IPEP). El IPEP es una guía que permite realizar un relevamiento ordenado y sistemático de los indicadores relacionados con las enfermedades peripartales sobre las variables del ambiente, los animales, la alimentación y los operarios. Es una herramienta metodológica que permite generar un diagnóstico a campo de las causas y factores predisponentes de las EP en establecimientos lecheros. A cada indicador se le asigna un número en una escala de 1 a 5, donde 1 es malo/pésimo; 2 es regular; 3 es bueno; 4 muy bueno y 5 es óptimo/excelente y los promedios de las variables da un IPEP final. El IPEP se aplicó en un tambo comercial, localizado en Brinkmann-Córdoba de 270 has, 210 vacas y 4200 litros de leche diarios. Se realizaron 4 visitas, se llenaron las planillas de indicadores del IPEP. Se observó el preparto, el rodeo en producción, las pasturas, las instalaciones y se habló con el personal. Se detectaron áreas en conflicto: dieta no balanceada, deficiente suplementación mineral, animales con pelaje seco, accesos en malas condiciones y la falta de una pileta pediluvio. En la primer visita abril de 2008 se realizó el IPEP y dio un valor de 3,11 , superior a 3 lo cual admite la calificación como tambo bueno. De acuerdo a la incidencia de EP y mortandad las pérdidas económicas para dicho IPEP fue de U$S 11.415, que equivalen al 7,3 por ciento de los ingresos por leche. Se propusieron correcciones y mejoró el índice, en septiembre del 2009, dio como resultado un IPEP de 3,71 y las perdidas económicas por EP y mortandad se estimaron en U$S 8.064, equivalentes al 0,43 de los ingresos por leche.

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Software metrics are the key tool in software quality management. In this paper, we propose to use support vector machines for regression applied to software metrics to predict software quality. In experiments we compare this method with other regression techniques such as Multivariate Linear Regression, Conjunctive Rule and Locally Weighted Regression. Results on benchmark dataset MIS, using mean absolute error, and correlation coefficient as regression performance measures, indicate that support vector machines regression is a promising technique for software quality prediction. In addition, our investigation of PCA based metrics extraction shows that using the first few Principal Components (PC) we can still get relatively good performance.

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Objective: The purpose of the study was to examine the relationship of surveillance and control activities in Canadian hospitals with rates of nosocomial methicillin-resistant S. aureus (MRSA), C. difficile associated diarrhea (CDAD), and vancomycin-resistant Enterococcus (VRE). Methods: Surveys were sent to Infection Control programs in hospitals that participated in an earlier survey of infection control practices in Canadian acute care hospitals. Results: One hundred and twenty of 145 (82.8%) hospitals responded to the survey. The mean MRSA rate was 2.0 (SD 2.9) per 1,000 admissions, the mean CDAD rate was 3.8 (SD 4.3), and the mean VRE rate was 0.4 (SD 1.5). Multiple stepwise regression analysis found hospitals that reported infection rates by specific risk groups (r = - 0.27, p < 0.01) and that kept attendance records of infection control teaching activities (r = - 0.23, p < 0.01) were associated with lower MRSA rates. Multiple stepwise regression analysis found larger hospitals (r = 0.25, p < 0.01) and hospitals where infection control committees or staff had the direct authority to close a ward or unit to further admissions due to outbreaks (r = 0.22, p < 0.05) were associated with higher CDAD rates. Multiple logistic regression analysis found larger hospitals (OR = 1.6, CI 1.2 - 2.0, p = 0.003) and teaching hospitals (OR = 3.7, CI 1.2 - 11.8, p = 0.02) were associated with the presence of VRE. Hospitals were less likely to have VRE when infection control staff frequently contacted physicians and nurses for reports of new infections (OR = 0.5, CI 0.3 - 0.7, p = 0.02) and there were in-service programs for updating nursing and ancillary staff on current infection control practices (OR = 0.2, CI 0.1 - 0.7, p = 0.01). Conclusions: Surveillance and control activities were associated with MRSA and CDAD rates and the presence of VRE. Surveillance and control activities might be especially beneficial in large and teaching hospitals.

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Parasites can structure biological communities directly through population regulation and indirectly by processes such as apparent competition. However, the role of parasites in the process of biological invasion is less well understood and mechanisms of parasite mediation of predation among hosts are unclear. Mutual predation between native and invading species is an important factor in determining the outcome of invasions in freshwater amphipod communities. Here, we show that parasites mediate mutual intraguild predation among native and invading species and may thereby facilitate the invasion process. We find that the native amphipod Gammarus duebeni celticus is host to a microsporidian parasite, Pleistophora sp. (new species), with a frequency of infection of 0-90%. However, the parasite does not infect three invading species, G. tigrinus, G. pulex and Crangonyx pseudogracilis. In field and laboratory manipulations, we show that the parasite exhibits cryptic virulence: the parasite does not affect host fitness in single-species populations, but virulence becomes apparent when the native and invading species interact. That is, infection has no direct effect on G. d. celticus survivorship, size or fecundity; however, in mixed-species experiments, parasitized natives show a reduced capacity to prey on the smaller invading species and are more likely to be preyed upon by the largest invading species. Thus, by altering dominance relationships and hierarchies of mutual predation, parasitism strongly influences, and has the potential to change, the outcome of biological invasions.

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