922 resultados para mononuclear and isolated TiOx


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Tap water is not sterile; it contains organisms which grow in water distribution systems or inside taps and their fittings. The absence of known pathogenic bacteria is assured by the absence of the indicator organisms but concerns have been raised in the past few years that drinking water fulfilling the standards laid down in the EC Directive ECC 80/778 may still cause disease. These concerns have arisen from several sources: the fact that a cause has been identified in only half of all suspected waterborne outbreaks of disease; reports have suggested that heterotrophic bacteria possessing single pathogenic mechanisms such as haemolysin may cause disease; reports of heterotrophic organisms causing water contact diseases in hospitals. These concerns led to a reappraisal of the pathogenic potential of heteretrophic bacteria, by carrying out an extensive literature search and review commissioned by the UK Water Research Company. This research identified many papers showing an association between drinking water and heterotrophic bacteria but only very few reports of suspected waterborne disease associated with the heterotrophs. The organisms demonstrating potential to cause disease were species of Aeromonas and Yersinia, but typing of organisms identified in patients and isolated from the water revealed very few similarities. The potential of Aeromonas and Yersinia to cause waterborne disease is thought to be very low and the Communicable Disease Surveillance Centre database of laboratory infections due to these two genera of organisms was analysed to produce population-related incidences for each health region in England and Wales. Additionally a laboratory questionnaire revealed different levels of ascertainment of these two organisms in different laboratories of the Public Health Laboratory Service.

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Nas últimas décadas, a disposição final de lixo tornou-se um sério problema a ser enfrentado por todos os países, em função da escassez crescente de terrenos disponíveis para aterros sanitários e distância cada vez maior dos centros geradores e a disposição final, assim como do aumento substancial da geração per capita. A acumulação de lixo nos grandes centros populacionais estimula a proliferação de macro e microvetores (ratos, baratas, moscas, vírus, bactérias, parasitos) e conseqüentemente, a disseminação de doenças. Em particular, com relação ao lixo gerado em ilhas e comunidades isoladas, é de alta relevância estratégias baseadas na descentralização do tratamento da fração orgânica de lixo domiciliar, com fim do transporte através de barcas para o continente, gerando mau cheiro e riscos de poluição ambiental. O presente projeto teve por objetivo: Testar o mesmo reator de compostagem descentralizada sob condições do verão sueco, alimentando-o com resíduos de restaurantes da cidade costeira Kalmar e sob condições brasileiras, alimentando-o com resíduos de cozinha da escola municipal de Abraão-Ilha Grande, RJ; propor modificações mecânicas e/ou operacionais para otimização dos processos; avaliar a qualidade e o grau de maturação do composto de diferentes fases através do método respirométrico Specific Oxygen Uptake Rate (SOUR)o método respirométrico NBR 14283 da ABNT. Em resumo, concluiu-se que a composição do lixo e pH inicial do material estruturante adicionado são fatores determinantes do tempo requerido para degradação dos ácidos orgânicos gerados e subseqüente elevação do pH; dependendo das características dos resíduos orgânicos, é necessária a inclusão de inoculante (ex: composto) para melhor desenvolvimento de bactérias e fungos e, conseqüentemente, otimização do processo; as análises físico-químicas e microbiológicas confirmaram que o processo de degradação aeróbia ocorre no interior do corpo principal do reator e que a qualidade do composto gerado é satisfatória; entretanto, melhorias consideráveis no sistema de trituração e alimentação são requeridas para que o reator testado possa se usado em sua capacidade plena. Os testes respirométrico atráves do Specific Oxygen Uptake Rate(SOUR) e da norma NBR 14283 da ABNT mostraram-se ambos eficazes na identificação do grau de maturação do composto e do avanço do processo de compostagem. Uma vez removidos os problemas mecânicos de trituração e alimentação, o reator testado poderá ser utilizado como uma tecnologia inovadora do tratamento de lixo orgânico in situ para pequenos e médios geradores de lixo orgânico domiciliar.

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Lonchophylla bokermanniSazima, Vizotto & Taddei, 1978 é uma espécie de morcego nectarívoro de médio porte endêmica do sudeste brasileiro. Pouco se sabe sobre sua biologia e distribuição geográfica, e por isso mesmo é classificada pela União para Conservação da Natureza (IUCN) como Deficiente de Dados. Está, no entanto, na lista brasileira da fauna ameaçada de extinção, sendo considerada Vulnerável por apresentar distribuição restrita, populações pequenas e isoladas, e estar vivenciando uma rápida destruição de seus habitats.Uma das mais importantes lacunas no conhecimento sobre L. bokermanni é o seu padrão de distribuição geográfica. Esta espécie possui uma distribuição disjunta, com uma forma na porção interior de sua distribuição, restrita aos arredores de sua localidade tipo, e uma forma com uma distribuição mais ampla, entre a Serra do Mar e o litoral. Existe a possibilidade de que a forma costeira possa corresponder a uma espécie ainda não descrita, visto que possui antebraços menores e algumas medidas cranianasdiferentes em relação a forma do interior.Nesta dissertação procuro gerar dados quantitativos mínimos necessários para determinar o status de conservação de L. bokermanni segundo os critérios da IUCN. Tendo em vista as incertezas taxonômicas, sempre que possível as análises foram feitas com três conjuntos de dados: i) todos os registros de ocorrência, assumindo que representam uma única espécie, ii) apenas com os dados da forma do interior, assumindo que representam L. bokermanni, e iii) apenas com os dados da forma costeira, assumindo que representam uma nova espécie. No primeiro capítulo foram identificadas áreas prioritárias para a busca de novas populações de L. bokermanni Essas áreas apresentam as condições climáticas e altitudinais típicas para a espécie, mantêm sua cobertura florestal, têm poucos inventários de quirópteros e estão fora da área de distribuição conhecida da espécie. O capítulo também apresenta o resultado da busca em campo por novas populações da espécie em três destas áreas prioritárias, ao sul da distribuição conhecida. No segundo capítulo a probabilidade de detecção e ocupação de Lonchophylla bokermanni foi modelada em escala regional e local, utilizando covariáveis ambientais e metodológicas que podem explicar os padrões encontrados. O grau de incerteza na distribuição conhecida da espécie foi avaliado, e estimou-se o esforço mínimo necessário para termos confiançana ausência da espécie em uma localidade. No terceiro capítulo a informação apresentada nos capítulos anteriores foi utilizada para determinar o status de conservação de L. bokermanni (segundo o critério de Extensão de Ocorrência da IUCN), discutir o estado atual de conhecimento sobre a espécie e as consequências de possíveis mudanças taxonômicas para seu status de conservação.

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O presente estudo objetivou construir uma história do Curso de Psicologia da Faculdade Salesiana de Filosofia, Ciência e Letras de Lorena, com a perspectiva de compreender as relações sociais, culturais, as práticas cotidianas e os modos de fazer que caracterizaram a constituição do curso, tendo como recorte histórico o período de 1952 a 1974. A meta final foi contribuir para a historiografia da Psicologia no Brasil. Apresentamos, inicialmente, de forma concisa, a história dos salesianos, desde sua criação e de sua inserção no Brasil. Detemo-nos mais em sua chegada à Lorena, com a fundação do Colégio São Joaquim e, muito mais especialmente, do Laboratório de Psicologia Experimental. Exploramos seu significado para os salesianos e sua missão educativa, bem como para a emergência do curso de Psicologia. Foram utilizados, como fontes documentais, documentos escritos e iconográficos, além disso, foram realizadas Entrevistas Narrativas, que nos possibilitaram apontar algumas características do começo do curso, como, por exemplo, as questões de gênero. Assinalamos como a abordagem experimental, dominante no primeiro momento do curso, em que os principais professores eram oriundos da USP e da PUC-SP, muda aos poucos para a abordagem humanista, ruptura causada pela presença de um professor, Franz Victor Rudio. Concluímos que o curso de Psicologia de Lorena emergiu não por um documento ou por uma ação intencional e isolada de um sujeito individual, mas por ação de muitos personagens que, durante um longo período, construíram práticas ligadas à Psicologia que levaram à constituição do curso. No entanto, pode-se afirmar que estas práticas foram fundamentadas na missão salesiana de formar educadores qualificados para o exercício do magistério, apoiada no tripé razão, religião e amorevolezza.

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Belugas, Delphinapterus leucas, in Cook Inlet, Alaska, represent a unique and isolated marine mammal population that has been hunted for a variety of purposes since prehistoric times. Archeological studies have shown that both Alutiiq Eskimos and Dena'ina Atabaskan Indians have long utilized many marine resources in Cook Inlet, including belugas. Over the past century, commercial whaling and sport hunting also occurred periodically in Cook Inlet prior to the Marine Mammal Protection Act of 1972 (MMPA). During the 1990's, the hunting mortality by Alaska Natives apparently increased to 40-70 whales per year, which led to the decling of this stock and its subsequent designation in 2000 as depleted under the MMPA. Concerns about the decline of the Cook Inlet stock resulted in a voluntary suspension of the subsistenc hunt by Alaska Natives in 1999. The difficulty in obtaining accurate estimates for the harvest of these whales is due to the inability to identify all of the hunters and, in turn, the size of the harvest. Attempts to reconstruct harvest records based on hunters' recollections and interviews from only a few households have been subject to a wide degree of speculation. To adequately monitor the beluga harvest, the National Marine Fisheries Service established marking and reporting regulations in October 1999. These rules require that Alaska Natives who hunt belugas in Cook Inlet must collect the lowere left jaw from harvested whales and complete a report that includes date and time of the harvest, coloration of the whale, harvest location, and method of harvest. The MMPA was amended in 2000 to require a cooperative agreement between the National Marine Fisheries Service and Alaska Native organizations before hunting could be resumed.

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A programme of research on the seismic behaviour of retaining walls has been under way at Cambridge since 1981. Centrifuge tests have presently been conducted both on cantilever walls and isolated mass walls, retaining dry sands of varying grading and density. This paper is devoted to the modelling of fixed-base cantilever walls retaining Leighton Buzzard (14/25) sand of relative density 99% with a horizontal surface level with the crest of the wall. The base of the centrifuge container was used to fix the walls, and to provide a rigid lower boundary for the sand. No attempt was made to inhibit the propagation of compression waves from the side of the container opposite the inside face of the model wall. The detailed analysis of dynamic deflections and bending moments was made difficult by the anelastic nature of reinforced concrete, and the difficulty of measuring bending strains thereon. A supplementary programme of well-instrumented tests on Dural walls of similar stiffness, including the modelling of models, was therefore carried out. Refs.

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Background: Habitat fragmentation may result in the reduction of diversity of parasite communities by affecting population size and dispersal pattern of species. In the flood plain of the Yangtze River in China, many lakes, which were once connected with the river, have become isolated since the 1950s from the river by the construction of dams and sluices, with many larger lakes subdivided into smaller ones by road embankments. These artificial barriers have inevitably obstructed the migration of fish between the river and lakes and also among lakes. In this study, the gastrointestinal helminth communities were investigated in a carnivorous fish, the yellowhead catfish Pelteobagrus fulvidraco, from two connected and five isolated lakes in the flood plain in order to detect the effect of lake fragmentation on the parasite communities. Results: A total of 11 species of helminths were recorded in the stomach and intestine of P. fulvidraco from seven lakes, including two lakes connected with the Yangtze River, i.e. Poyang and Dongting lakes, and five isolated lakes, i.e. Honghu, Liangzi, Tangxun, Niushan and Baoan lakes. Mean helminth individuals and diversity of helminth communities in Honghu and Dongting lakes was lower than in the other five lakes. The nematode Procamallanus fulvidraconis was the dominant species of communities in all the seven lakes. No significant difference in the Shannon-Wiener index was detected between connected lakes (0.48) and isolated lakes (0.50). The similarity of helminth communities between Niushan and Baoan lakes was the highest (0.6708), and the lowest was between Tangxun and Dongting lakes (0.1807). The similarity was low between Dongting and the other lakes, and the similarity decreased with the geographic distance among these lakes. The helminth community in one connected lake, Poyang Lake was clustered with isolated lakes, but the community in Dongting Lake was separated in the tree. Conclusion: The similarity in the helminth communities of this fish in the flood-plain lakes may be attributed to the historical connection of these habitats and to the completion of the life-cycles of this fish as well as the helminth species within the investigated habitats. The diversity and the digenean majority in the helminth communities can be related to the diet of this fish, and to the lacustrine and macrophytic characters of the habitats. The lake isolation from the river had little detectable effect on the helminth communities of the catfish in flood-plain lakes of the Yangtze River. The low similarities in helminth communities between the Dongting Lake and others may just be a reflection of its unique water environment and anthropogenic alterations or fragmentation in this lake.

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The white cloud mountain minnow Tanichthys albonubes Lin is an endemic species to southern China and the genus has two species, Tanichthys albonubes Lin and Tanichthys micagemmae Freyhof et Herder. The distribution range of T. albonubes Lin and T. micagemmae is very narrow and only found in the mountain brooks of Baiyunshan Mountain (White Cloud Mountain), Huaxian Country and the vicinity of Guangzhou in Guangdong Province and Halong, Quang Ninh Province, Vietnam respectively. The wild populations of this fish had already been on the verge of extinction when Shu-Yan Lin first discovered it in 1932 at the Baiyunshan Mountain. It was believed to be extinct in the wild because there were no reports of this fish in the wild since 1980. In September 2003, a small and isolated population of the fish was discovered in a mountain puddle in the north vicinity of Guangzhou. Additional studies are needed to determine the survival and propagation of the released fish. The protection of their natural habitat should be implemented.

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Although long chain alkenones (LCKs) occur widely in lacustrine sediments, their origin is not clear. Here, we report a lacustrine source, the non-calcifying species Chrysotila lamellosa Anand (Haptophyceae), collected and isolated from an inland saline water body, Lake Xiarinur (Inner Mongolia, China). Its alketione pattern is similar to those of coastal marine strains of C lamellosa,but the relationship between U-37(K') index and culture temperature for the lacustrine species is quite different from that of the coastal species. A significant feature of the alkenones in this strain of C lamellosa is a lack of C-38 methyl alkenones, which might be used to distinguish the species from the marine haptophyte species Emiliania huxleyi and Gephyrocapsa oceanica. The higher C-38 tetraunsaturated compound abundance might be another important feature for distinguishing the C lamellosa alkenone producer from the coastal species Isochrysis galbana. This alkenone distribution pattern has been detected in many lakes, which suggests that C lamellosa or a closely related species might be a very common alkenone precursor in lacustrine systems. We examined U-37(K') and U-37(K) values for C lamellosa as a function of culture temperature in a batch culture experiment. The calibration for U-37(K') vs. culture temperature (T) was U-37(K') = 0.0011 x T-2 - 0.0157 x T + 0.1057(n = 14, r(2) = 0.99) from 10 degrees C to 22 degrees C or U-37(K') = 0.0257 x T - 0.2608(n = 9, r(2) = 0.97) from 14 degrees C to 22 degrees C. U-37(K) vs. culture temperature was U-37(K) = 0 0377 x T - 0.5992(n = 14, r(2) = 0.98) from 10 degrees C to 22 degrees C. Our experiments show that the alkenone unsaturation index (U-37(K')) is strongly controlled by culture temperature and can be used for palaeoclimate reconstruction. (C) 2007 Elsevier Ltd. All rights reserved.

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Lake Dianchi is in Yunnan Province in southwestern China. In recent years, significant cyanobacterial blooms have occurred in this lake nearly every year because of eutrophication. Monitoring data for the past 5 years acquired by our research group showed that phytoplankton composition alternated between species of Microcystis sp. during warm seasons and those of Aphanizomenon sp. during cool seasons. In March 2003, when phytoplankton composition was highly dominated by Aphanizomenon sp., samples were taken from the lake for toxin detection and immediate strain isolation. A mouse bioassay with extracts from the lyophilized field material showed obvious intoxication from paralytic shellfish poisons (PSPs), and all mice died within 30 min. Further analysis of both field and isolated algal strain Aphanizomenon DC-1 by the postcolumn HPLC-FLD method confirmed its PSP-producing ability The analogues found in the extracts from the field material were neoSTX, dcSTX, and dcGTX3, with contents of 2.279, 1.135, and 0.547 ng/mg DW, respectively. Under laboratory culture condition, toxin content in the Aphanizomenon strain DC-1 varied greatly during different growth phases, with two peaks: in the early-exponential and late-stationary growth phases. When the culture grew at a relatively high rate during the mid- to late-exponential growth phase, toxin content declined gradually. Moreover, the types of toxin in the DC-1 strain varied greatly during a single culture cycle. The HPLC results showed that dcSTX was the only toxin isomer detected throughout the culture period, and its level remained stable. On the other hand, dcGTX2 and GTX4 were the major toxins during the early-exponential and stationary phases, respectively. This article presents the first data on the identification and detection of paralytic shellfish toxins from cyanobacteria in Lake Dianchi. As far as we know, this is also the first report of this type of toxin in inland water bodies in China. Our study indicates the threat associated with PSP toxins in Lake Dianchi and suggests that necessary measures and programs for control are urgently needed to prevent the spread of toxic cyanobacterial blooms. (c) 2006 Wiley Periodicals, Inc.

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A rhabdovirus was found to be associated with a lethal hemorrhagic disease in the cultured Chinese sucker Myxocyprinus asiaticus Bleeker. The rhabdovirus was amplified and isolated from the infected GCO, (grass carp ovary) cells. In ultrathin sections of liver cells from the diseased fish, the virus particles exhibited the characteristic bacilliform morphology, and budded through vesicle membranes of the infected cells. The isolated rhabdovirus particles were found to have a bacilliform morphology with 2 rounded ends rather than a typical flat base. The virus particles were measured and ranged in size from 150 to 200 nm in length and 50 to 60 nm in diameter. Most other characteristics, including their size, extensive virus infectivity to fish cell Lines, strong cytopathogenic effects, stability at high temperatures, vesicle formation in infected cells, structure protein electrophoretic patterns and the presence of an RNA genome, very closely resembled those of other fish rhabdoviruses. At present it is not known if this is a novel virus species or if it is an isolate of a known fish rhabdovirus. Until a confirmed identification can be made, we will temporarily refer to this virus as Chinese sucker rhabdovirus (CSRV).

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黄土高原沟壑区王东沟流域从1986年至2006年的土地利用/覆被发生了较大变化,土地利用动态指数分别为:耕地3.21%,园地-36.11%,林地-4.05%,牧草地4.24%,居民点及独立工矿用地-0.62%,交通运输用地-12.27%,未利用地1.85%;变化趋势是:耕地逐年向园地流转,园地变化烈度较大,其他各类用地变化不太显著。引起这一变化的主要因素是自然、社会、经济、技术以及政策因素。结合这一变化,针对黄土高原沟壑区的实际情况,在黄土高原沟壑区土地利用经营与管理方面,应重视土地产出效益与粮食安全的关系,在保障区域粮食安全的基础上实现效益最大化。

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Complexes of vacancy at indium site with one to four hydrogen atoms and isolated hydrogen or hydrogen dimer and other infrared absorption lines, tentatively be assigned to hydrogen related defects were investigated by FTIR. Hydrogen cam passivate imperfections, thereby eliminating detrimental electronic states from the energy bandgap. Incorporated hydrogen can introduce extended defects and generate electrically-active defects. Hydrogen also can acts as an actuator for creating of antistructure defects. Isolated hydrogen related defects(e.. H-2*) may play an important role in the conversion of the annealed wafers from semiconducting to the semi-insulating behavior. H-2* may be a deep donor, whose energy level is very near the iron deep acceptor level in the energy gap.

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Dynamics of formation of defects in the annealed nominally undoped semi-insulating InP obtained by high pressure, high temperature annealing of high purity materials is proposed. Incorporated hydrogen passivates vacancy at indium site from annihilation forming fully hydrogenated indium vacancy which dissociates leaving large lattice relaxation behind, deep donors, mainly larger complexes involving phosphorus at indium site and isolated hydrogen defects are created in nominally undoped InP after annealing. Also created are acceptor levels such as vacancy at indium site. Carrier charge compensation mechanism in nominally undoped InP upon annealing at high temperature is given. Microscopic models of hydrogen related defects are given. Structural, electronic and vibrational properties of LVMs related to hydrogen as well as their temperature effect are discussed.

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Dynamical formation mechanism of defects in the annealed nominally undoped semi-insulating InP obtained by high pressure, high temperature annealing of high purity materials is proposed. Local vibrational modes in tenths of InP samples reveal clearly existence of complexes related to hydrogen. Complexes of vacancy at indium site with one to four hydrogen atoms and isolated hydrogen or hydrogen dimers, complexes of hydrogen with various impurities are investigated by FTIR. Hydrogen can acts as an actuator for generation of antistructure defects. Fully hydrogenated indium vacancy dissociates leaving large lattice relaxation behind, deep donors, mainly larger complexes involving phosphorus at indium site and isolated hydrogen defects are created in nominally undoped InP after annealing. Also created are acceptor levels such as vacancy at indium site. Carrier charge compensation mechanism in nominally undoped InP upon annealing at high temperature is given. Microscopic models of hydrogen related defects are given. Structural, electronic and vibrational properties of LVMs related to hydrogen as well as their temperature effect are discussed.