An Enantiospecific Approach to Tetraquinane Diterpenes Crinipellins: Synthesis of Norcrinipellins

An enantiospecific approach to the synthesis of tetraquinane diterpene crinipellins is described. The cyclopentane ring in campholenaldehyde was identified as the B ring. Two rhodium carbenoid CH insertion reactions for the construction of A and C rings and an intramolecular Michael addition reaction for the D ring of crinipellins were employed as key strategies for the enantiospecific synthesis of norcrinipellins.

Growth and characterization of SrBi2Nb2O9 thin films by pulsed-laser ablation

Polycrystalline films of SrBi2Nb2O9 were grown using pulsed-laser ablation. The ferroelectric properties were achieved by low-temperature deposition followed by a subsequent annealing process. The lower switching voltage was obtained by lowering the thickness, which did not affect the insulating nature of the films. The hysteresis results showed an excellent square-shaped loop with results (Pr = 6 μC/cm2, Ec = 100 kV/cm) in good agreement with earlier reports. The films also exhibited a dielectric constant of 250 and a dissipation factor of 0.02. The transport studies indicated an ohmic behavior, while higher voltages induced a bulk space charge.

A meta-analysis of the traits affecting dispersal ability in butterflies: can wingspan be used as a proxy?

1. Dispersal ability of a species is a key ecological characteristic, affecting a range of processes from adaptation, community dynamics and genetic structure, to distribution and range size. It is determined by both intrinsic species traits and extrinsic landscape-related properties. 2. Using butterflies as a model system, the following questions were addressed: (i) given similar extrinsic factors, which intrinsic species trait(s) explain dispersal ability? (ii) can one of these traits be used as a proxy for dispersal ability? (iii) the effect of interactions between the traits, and phylogenetic relatedness, on dispersal ability. 3. Four data sets, using different measures of dispersal, were compiled from published literature. The first data set uses mean dispersal distances from capture-mark-recapture studies, and the other three use mobility indices. Data for six traits that can potentially affect dispersal ability were collected: wingspan, larval host plant specificity, adult habitat specificity, mate location strategy, voltinism and flight period duration. Each data set was subjected to both unifactorial, and multifactorial, phylogenetically controlled analyses. 4. Among the factors considered, wingspan was the most important determinant of dispersal ability, although the predictive powers of regression models were low. Voltinism and flight period duration also affect dispersal ability, especially in case of temperate species. Interactions between the factors did not affect dispersal ability, and phylogenetic relatedness was significant in one data set. 5. While using wingspan as the only proxy for dispersal ability maybe problematic, it is usually the only easily accessible species-specific trait for a large number of species. It can thus be a satisfactory proxy when carefully interpreted, especially for analyses involving many species from all across the world.

Enantiospecific first total synthesis of (6S,7R)-silphiperfolan-6-ol

Enantiospecific first total synthesis of the angular triquinane sesquiterpene (65,7R)-silphiperfolan-6-ol has been accomplished, starting from 2-(3-isopropenyl-2-methylene-1-methylcyclopent-1-yl)acetic acid (readily available from (R)-limonene) employing an efficient, regioselective intramolecular rhodium carbenoid insertion into the CH bond of a tertiary methyl group as the key step. (C) 2012 Elsevier Ltd. All rights reserved.

Differences in host species relationships and biogeographic influences produce contrasting patterns of prevalence, community composition and genetic structure in two genera of avian malaria parasites in southern Melanesia

1. Host-parasite interactions have the potential to influence broadscale ecological and evolutionary processes, levels of endemism, divergence patterns and distributions in host populations. Understanding the mechanisms involved requires identification of the factors that shape parasite distribution and prevalence. 2. A lack of comparative information on community-level host-parasite associations limits our understanding of the role of parasites in host population divergence processes. Avian malaria (haemosporidian) parasites in bird communities offer a tractable model system to examine the potential for pathogens to influence evolutionary processes in natural host populations. 3. Using cytochrome b variation, we characterized phylogenetic diversity and prevalence of two genera of avian haemosporidian parasites, Plasmodium and Haemoproteus, and analysed biogeographic patterns of lineages across islands and avian hosts, in southern Melanesian bird communities to identify factors that explain patterns of infection. 4. Plasmodium spp. displayed isolation-by-distance effects, a significant amount of genetic variation distributed among islands but insignificant amounts among host species and families, and strong local island effects with respect to prevalence. Haemoproteus spp. did not display isolation-by-distance patterns, showed marked structuring of genetic variation among avian host species and families, and significant host species prevalence patterns. 5. These differences suggest that Plasmodium spp. infection patterns were shaped by geography and the abiotic environment, whereas Haemoproteus spp. infection patterns were shaped predominantly by host associations. Heterogeneity in the complement and prevalence of parasite lineages infecting local bird communities likely exposes host species to a mosaic of spatially divergent disease selection pressures across their naturally fragmented distributions in southern Melanesia. Host associations for Haemoproteus spp. indicate a capacity for the formation of locally co-adapted host-parasite relationships, a feature that may limit intraspecific gene flow or range expansions of closely related host species.

Saturated duration of rectangular pressure pulse applied to rectangular plates with finite-deflections

The inequities in health care and housing access experienced by low-income women in the United States are a continuing concern. This article addresses the interrelationships between housing and health as experienced by low-income clients so that health care practitioners can begin to build active and effective health-promoting partnerships with clients, their families, and their communities. A case study is presented that describes the actual experience of a woman living in a low-income housing development and its effect on her health and access to health care. The importance of the role of midwives in addressing the health care and advocacy needs of women in substandard housing is highlighted.

Estudio de las propiedades quimicas, anatomicas y fisico-mecanicas de la madera de tres especies forestales de importancia economica

El Enterolobium Cyclocarpum, segun se determino en el estudio anatomico, tiene un alto contenido de Parènquima, fibras cortas y bajas indice de calidad de pulpas que lo hace inadecuado para la fabricación de papel; por sus bajos valores de densidad, elasticidad y resistencia a los esfuerzos mecánicos, no es recomendable su uso en estructura de soportes en la construcción. sin embargo su color y textura le proporcionan alto valor estético apreciado en la fabricación de muebles, decoloraciones, puertas. También posee un considerable contenido de extraible que le proporcionan durabilidad natural, lo que sumado a su bajo indice de contradicción hinchamiento, lo hace optimo para su utilización en exteriores. Pinus: por sus características microscópicas como fibras largas, muy poco parentima y alto indice de calidad de pulpa, lo hacen optimo para la fabricación de papel. su propiedades elásticas y de resistencia lo sitúan por arriba de valores intermedios, que convierten a esta especie apta para la construcción, fabricación, de chapas, muebles, juguetes, artículos deportivos, artesanía muchos otros usos. contiene extraibles en regular cantidad, principalmente del tipo resinico, ampliamante utilizado en la industria. El cuercus, caracterizado por tener fibras largas en comparación con otras latifoliados, y un indice de calidad de pulpas intermedio, puede ser apto para la fabricación de papel. sus valores propiedades ficicas y mecánicas son los mas altos de las tres maderas ensayadas, por lo que su madera ofrece un gran potencial de utilización de la fabricación de juguetes, muebles piezas torneadas postes, y elementos estructurales, y piezas de maquinaria. El conocimiento de la estructuras, propiedades tecnológicas y químicas de nuestra madera, constituye la base para su aprovechamiento integral y una adecuada utilización de especies que por tradición o desconocimiento no se les ha dado el uso correcto. por la importancia económica que tiene las especies estudiadas, se justifica ampliar sus estudios, partiendo de la metodología empleada en este trabajo, pues en su mayor parte resulta de aplicación practica en las condiciones actuales de nuestro país. la información bibliográfica recabada constituye una base importante para posteriores estudios relacionados con la anatomía, propiedades físicas y mecánicas, secado, y químico de la madera.

Anuario Estadistico de Pesca 1990

This document is in Spanish. El capítulo 1, se conforma por un conjunto de cuadros referidos a los resultados que se obtuvieron en la fase primaria del circuito productivo, es decir, la producción derivada de las capturas y de la acuacultura practicadas con fines comerciales. Las variables de producción consignadas se refieren a las di-mensiones más representativas de la actividad: volumen y valor de la producción por especies, producción por tipo de destino, por sectores productivos, por litoral y entidad federativa y por principales Oficinas de Pesca. Este capítulo se concluye presentando un grupo de cuadros sobre la produccion proveniente de la acuacultura, ademis de algunas series historicas referidas al comportamiento de las principales pesquerías y de la produccion nacional en su conjunto. Enseguida -Capítulo 11-, se da a conocer la informaci6n relativa a la industrializaci6n de la produccion pesouera, destacando las variables referidas a la materia prima procesada, producto obtenido y principales procesos industriales, esto es, el congelado, enlatado, reducci6n y otros procesos. En el Capítulo 111, se presentan las estadísticas sobre la comercializacion interna y externa de productos pesqueros. De modo que, aquí se expresan variables tales como el consumo aparente y per cipita, disponibilidad interna de productos pesqueros, precios y la Balanza Comercial Pesquera, entre -las mas importantes. El Capítulo IV, da cabida a la informacion sobre los factores de la produccion. Es decir, en esta parte del Anuario se concentra la informacion relativa a los acervos de capital -activos pesqueros-, fuerza de trabajo y financiamiento. Por último, el Capítulo V recoge informacion pesquera de caracter internacional, con el proposito de ubicar la participacion de nuestro país en el concierto mundial de la pesca. Destacan aquí agregados como la producci6n, industrializaci6n, comercializaci6n y consumo de productos pesqueros. Catch statistics for Mexican waters 1990. (PDF has 110 pages.)

Transfronteirização e Financiamento dos Serviços de Saúde: uma reflexão a partir de Foz do Iguaçu-PR.

A fronteira é uma área fragilizada; o trânsito livre de pessoas na região faz com que ela seja altamente vigiada, tanto para a segurança quanto o contrabando e tráfico. Essa facilidade de acesso no transito entre os países, traz um número de pessoas que fazem um trajeto longo, muitas vezes com risco de vida eminente, em busca de assistência médica, inexistente no seu país de origem. O pagamento dessa fatura é de responsabilidade do país que realizou o atendimento, assim como a estatística. Os gestores estaduais e municipais tentam contornar essa situação da melhor maneira possível, sem causar perdas financeiras no seu orçamento. A partir da experiência internacional de parcerias entre cidades de fronteira (transfronteirização), esta dissertação tem como eixo principal analisar o caso do município de Foz do Iguaçu, onde a problemática da política brasileira de saúde nas fronteiras se revela em sua potência máxima. O trabalho apresenta a situação do financiamento da saúde na fronteira oeste do Estado do Paraná, propondo um termo de cooperação na assistência e no financiamento.

大型底栖动物体长体重关系和生化组成的研究

求出了 17种常见底栖动物的体长、体重 (干、湿 )关系 .一般情况下 ,b值略小于 3.0 .测定了 16种经济底栖动物的生化组分 ,蛋白质质量分数超过 5 0 %的有 14种 ,其中背摇蚊的最高 ,为 71.7% ;脂类质量分数超过 2 0 %的有 6种 ,其中苏氏尾鳃蚓、单孔蚓的最高 ,为 33.36 % ;灰分质量分数超过 10 %的有 10种 ,其中克氏螯虾和溪蟹一种分别达到 39.3%和 5 8.9% ;碳水化合物的质量分数一般低于 10 % .

一种由苯脲和甲醇合成苯氨基甲酸甲酯的方法

一种由苯脲和甲醇合成苯氨基甲酸甲酯的方法是将苯基脲、溶剂、甲醇和催化剂加入反应器中，用惰性气体对反应器进行置换后，密闭反应釜，在搅拌状态下，以４～１０℃／ｍｉｎ的升温速率，升温至１４５～１７０℃，反应在该温度和自生压力下反应３－５小时。本发明反应条件温和、操作过程简单、催化剂价廉易得、反应选择性好、产物分离容易，是一种满足工业化需求、实用性很强的方法。

Enrichment and hydrogen production by marine anaerobic hydrogen-producing microflora

Acid, alkali, heat-shock, KNO3 and control pretreatment methods applied to anaerobic sludge were evaluated for their ability to selectively enrich the marine hydrogen-producing mixed microflora. Seawater culture medium was used as the substrate. The hydrogen yield of pretreated microflora was higher than that of the un-pretreated control (P < 0.05). Among the pretreatment methods studied, heat-shock pretreatment yielded the greatest hydrogen production, which was 14.6 times that of the control. When the effect of initial pH on hydrogen production of heat-shock pretreated samples was studied, hydrogen was produced over the entire pH range (pH 4-10). The hydrogen yield peaked at initial pH 8 (79 mL/g sucrose) and then steadily decreased as the initial pH increased. Sucrose consumption was high at neutral initial pH. During the process of hydrogen production, pH decreased gradually, which indicated that the acquired microflora consisted of acidogenic bacteria.