983 resultados para Multiple Bonding Sites
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A new modeling approach-multiple mapping conditioning (MMC)-is introduced to treat mixing and reaction in turbulent flows. The model combines the advantages of the probability density function and the conditional moment closure methods and is based on a certain generalization of the mapping closure concept. An equivalent stochastic formulation of the MMC model is given. The validity of the closuring hypothesis of the model is demonstrated by a comparison with direct numerical simulation results for the three-stream mixing problem. (C) 2003 American Institute of Physics.
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The movements of the ricefield rats (Rattus argentiventer) near a trap-barrier system (TBS) were assessed in lowland flood-irrigated rice crops in West Java, Indonesia, to test the hypothesis that a TBS with a 'trap-crop' modifies the movements of rats within 200 m from the trap-crop. The home range use and locations of rat burrows were assessed using radiotelemetry at two sites, one with a TBS with trap-crop (Treatment site, the crop inside the fence was planted 3 weeks earlier than the surrounding crop) and the other with a TBS without trap-crop (Control site, the crop inside the fence was planted at the same time as the surrounding crop). Each TBS was a 50 x 50 m plastic fence with eight multiple-capture rat traps set at the base. More than 700 rats were caught in the TBS with trap-crop, whereas only 10 rats were caught in the TBS without trap-crop. The home range size of females was significantly smaller at the Treatment site (0.96 ha) than the Control site (2.99 ha), but there was no difference for males. Seventy-eight per cent of rats caught in the TBS and fitted with radiocollars had their daytime burrow locations within 200 m of the TBS. We could not determine if the rats caught in the TBS were residents or transients according to demographic parameters. Our results support the hypothesis that a TBS with a trap-crop protects the surrounding rice crop out to a distance of at least 200 m.
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Multiple HLA class I alleles can bind peptides with common sequence motifs due to structural similarities in the peptide binding cleft, and these groups of alleles have been classified into supertypes. Nine major HLA supertypes have been proposed, including an A24 supertype that includes A*2301, A*2402, and A*3001. Evidence for this A24 supertype is limited to HLA sequence homology and/or similarity in peptide binding motifs for the alleles. To investigate the immunological relevance of this proposed supertype, we have examined two viral epitopes (from EBV and CMV) initially defined as HLA-A*2301-binding peptides. The data clearly demonstrate that each peptide could be recognized by CTL clones in the context of A*2301 or A*2402; thus validating the inclusion of these three alleles within an A24 supertype. Furthermore, CTL responses to the EBV epitope were detectable in both A*2301(+) and A*2402(+) individuals who had been previously exposed to this virus. These data substantiate the biological relevance of the A24 supertype, and the identification of viral epitopes with the capacity to bind promiscuously across this supertype could aid efforts to develop CTL-based vaccines or immunotherapy. The degeneracy in HLA restriction displayed by some T cells in this study also suggests that the dogma of self-MHC restriction needs some refinement to accommodate foreign peptide recognition in the context of multiple supertype alleles.
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Background Estimates of the disease burden due to multiple risk factors can show the potential gain from combined preventive measures. But few such investigations have been attempted, and none on a global scale. Our aim was to estimate the potential health benefits from removal of multiple major risk factors. Methods We assessed the burden of disease and injury attributable to the joint effects of 20 selected leading risk factors in 14 epidemiological subregions of the world. We estimated population attributable fractions, defined as the proportional reduction in disease or mortality that would occur if exposure to a risk factor were reduced to an alternative level, from data for risk factor prevalence and hazard size. For every disease, we estimated joint population attributable fractions, for multiple risk factors, by age and sex, from the direct contributions of individual risk factors. To obtain the direct hazards, we reviewed publications and re-analysed cohort data to account for that part of hazard that is mediated through other risks. Results Globally, an estimated 47% of premature deaths and 39% of total disease burden in 2000 resulted from the joint effects of the risk factors considered. These risks caused a substantial proportion of important diseases, including diarrhoea (92%-94%), lower respiratory infections (55-62%), lung cancer (72%), chronic obstructive pulmonary disease (60%), ischaemic heart disease (83-89%), and stroke (70-76%). Removal of these risks would have increased global healthy life expectancy by 9.3 years (17%) ranging from 4.4 years (6%) in the developed countries of the western Pacific to 16.1 years (43%) in parts of sub-Saharan Africa. Interpretation Removal of major risk factors would not only increase healthy life expectancy in every region, but also reduce some of the differences between regions, The potential for disease prevention and health gain from tackling major known risks simultaneously would be substantial.
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We report the development of epitope-blocking enzyme-linked immunosorbent assays (ELISAs) for the rapid detection of serum antibodies to West Nile virus (WNV) in taxonomically diverse North American avian species. A panel of flavivirus-specific monoclonal antibodies (MAbs) was tested in blocking assays with serum samples from WNV-infected chickens and crows. Selected MAbs were further tested against serum samples from birds that represented 16 species and 10 families. Serum samples were collected from birds infected with WW or Saint Louis encephalitis virus (SLEV) and from noninfected control birds. Serum samples from SLEV-infected birds were included in these experiments because WNV and SLEV are closely related antigenically, are maintained in similar transmission cycles, and have overlapping geographic distributions. The ELISA that utilized MAb 3.11126 potentially discriminated between WW and SLEV infections, as all serum samples from WNV-infected birds and none from SLEV-infected birds were positive in this assay. Assays with MAbs 2132 and 6B6C-1 readily detected serum antibodies in all birds infected with WNV and SLEV, respectively, and in most birds infected with the other virus. Two other MAbs partially discriminated between infections with these two viruses. Serum samples from most WNV-infected birds but no SLEV-infected birds were positive with MAb 3.676, while almost all serum samples from SLEV-infected birds but few from WNV-infected birds were positive with MAb 6B5A-5. The blocking assays reported here provide a rapid, reliable, and inexpensive diagnostic and surveillance technique to monitor WNV activity in multiple avian species.
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Expression of metallothionein, an antioxidant induced by a variety of stimuli including ultraviolet light, was quantitated by immunohistochemistry in the skin of males aged over 50 who had known short- and long-term exposures to sunlight. Skin punch biopsies were taken from two sites in each subject: the hand in all subjects and a range of other sites matched to patients with a previously excised primary melanoma. Metallothionein expression (strongest in the basal layers of the epidermis and primarily nuclear) was associated with both short- and long-term exposure to sunlight. A plateau of staining intensity was reached after 3 h sun exposure, within the previous 3 d before biopsy. Expression was also elevated in the nonexposed skin sites of subjects who had recent sun exposure, indicating a systemic response to exposure of remote sites. Using the skin of the hand to normalize responses to chronic exposure between individuals, the systemically modulated response to sunlight was significantly greater on the unexposed back than on other sites. The possibility of ultraviolet-induced cytokines selectively modifying the response of skin on a site-specific basis was investigated. The circulating leukocytes, but not lymphocytes, of two individuals exposed to 1 minimal erythema dose whole-body solar-simulated ultraviolet showed increased interleukin-6 mRNA 4 h after exposure. Interleukin-6 was not directly induced in these cell populations 4 h after ultraviolet A or ultraviolet B irradiation ex vivo . Leukocytes may therefore contribute to and amplify the systemic effects of ultraviolet-induced interleukin-6 and metallothionein expression.
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One of the major regulators of mitosis in somatic cells is cdc25B. cdc25B is tightly regulated at multiple levels. The final activation step involves the regulated binding of 14-3-3 proteins. Previous studies have demonstrated that Ser-323 is a primary 14-3-3 binding site in cdc25B, which influences its activity and cellular localization. 14-3-3 binding to this site appeared to interact with the N-terminal domain of cdc25B to regulate its activity. The presence of consensus 14-3-3 binding sites in the N-terminal domain suggested that the interaction is through direct binding of the 14-3-3 dimer to sites in the N-terminal domain. We have identified Ser-151 and Ser-230 in the N-terminal domain as functional 14-3-3 binding sites utilized by cdc25B in vivo. These low affinity sites cooperate to bind the 14-3-3 dimer bound to the high affinity Ser-323 site, thus forming an intramolecular bridge that constrains cdc25B structure to prevent access of the catalytic site. Loss of 14-3-3 binding to either N-terminal site relaxes cdc25B structure sufficiently to permit access to the catalytic site, and the nuclear export sequence located in the N-terminal domain. Mutation of the Ser-323 site was functionally equivalent to the mutation of all three sites, resulting in the complete loss of 14-3-3 binding, increased access of the catalytic site, and access to nuclear localization sequence.
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Three pathological fractures occurred secondary to osteolytic lesions of multiple myeloma. Two long bone fractures were each stabilised using interlocking nail fixation augmented with polymethyl meth acral ate bone cement. One vertebral fracture was stabilised using Steinmann pins and PMMA. Successful stabilisation, rapid return to function and improvement in quality of life occurred in all fractures. The patient survived approximately eight months on concurrent chemotherapy.
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The interactions of chi-conopeptide MrIA with the human norepinephrine transporter (hNET) were investigated by determining the effects of hNET point mutations on the inhibitory potency of MrIA. The mutants were produced by site-directed mutagenesis and expressed in COS-7 cells. The potency of MrIA was greater for inhibition of uptake by hNET of [H-3] norepinephrine (K-i 1.89 muM) than [H-3] dopamine (K-i 4.33 muM), and the human dopamine transporter and serotonin transporter were not inhibited by MrIA ( to 7 muM). Of 18 mutations where hNET amino acid residues were exchanged with those of the human dopamine transporter, MrIA had increased potency for inhibition of [H-3] norepinephrine uptake for three mutations ( in predicted extracellular loops 3 and 4 and transmembrane domain (TMD) 8) and decreased potency for one mutation (in TMD6 and intracellular loop (IL) 3). Of the 12 additional mutations in TMDs 2, 4, 5, and 11 and IL1, three mutations (in TMD2 and IL1) had reduced MrIA inhibitory potency. All of the other mutations tested had no influence on MrIA potency. A comparison of the results with previous data for desipramine and cocaine inhibition of norepinephrine uptake by the mutant hNETs reveals that MrIA binding to hNET occurs at a site that is distinct from but overlaps with the binding sites for tricyclic antidepressants and cocaine.
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The design of randomized controlled trials entails decisions that have economic as well as statistical implications. In particular, the choice of an individual or cluster randomization design may affect the cost of achieving the desired level of power, other things being equal. Furthermore, if cluster randomization is chosen, the researcher must decide how to balance the number of clusters, or sites, and the size of each site. This article investigates these interrelated statistical and economic issues. Its principal purpose is to elucidate the statistical and economic trade-offs to assist researchers to employ randomized controlled trials that have desired economic, as well as statistical, properties. (C) 2003 Elsevier Inc. All rights reserved.
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Using synchrotron X-ray grazing incidence diffraction, superlattice structures have been observed to develop in Langmuir-Blodgett films of cadmium arachidate as the temperature is raised. The previously reported superstructure in the stacked lamellae at room temperature changes at about 70 degreesC and there are further changes at about 90 and 103 degreesC before the major phase transition from stacked lamellae to hexagonally packed rods occurs at 107 degreesC (Langmuir 1997, 13, 1602). Between 70 and 103 degreesC there is a 1 x 10 one-dimensional in-plane superstructure, which is commensurate with the local structure and has an interlayer shift along [01] by a distance of b (of the local structure) at lower temperatures, and a further shift at about 90 degreesC. At lower (
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O Comit?? Gestor para os sites da ENAP, inst??ncia institu??da pela Portaria n?? 173, de 25 de setembro de 2012, cujas atribui????es est??o relacionadas aos sites da ENAP, teve participa????o ativa durante os anos de 2012 e 2013, per??odo em que estiveram envolvidos no processo de constru????o da proposta do novo Portal da ENAP, atualmente em desenvolvimento.
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Problematiza a constituição do currículo (e da “formação docente” no campo curricular), no cotidiano escolar, na dimensão das conversações. Objetiva acompanhar os movimentos curriculares concernentes ao Proeja entre formas e forças complexas no cotidiano do Ifes – campus Venda Nova do Imigrante (VNI). Compõe com as linhas de pensamentos principalmente de Alves (2008, 2010, 2012); Carvalho (2004, 2008a, 2008b, 2009, 2012); Deleuze (1988, 2002, 2010); Deleuze e Guattari (1995); Ferraço (2007, 2008a, 2008b); Garcia (2011); Guattari (1987, 2004, 2012); Kastrup (2009, 2013); Lopes e Macedo (2011); Lopes (2010, 2011); Oliveira (2005, 2009, 2012); Paiva (2004, 2009); Rolnik (1989); e Spinoza (2013), entremeando os conceitos de movimentos e afetos no campo do currículo em redes na relação híbrida com os encontros-formações docente do/no Proeja. Adota a (não) metodologia cartográfica ao acompanhar movimentos curriculares (des)(re)territorializantes nas redes de conversações, especialmente nos encontrosformações: “Rodas de conversas com professores e demais servidores do Proeja”. Utiliza como principais instrumentos metodológicos a observação participante, a gravação das vozes e o registro em diário de campo. Contribui para outros movimentos de pesquisa ao capturar produzir e analisar dados em que se percebe que: ainda que tenha ocorrido um planejamento coletivo, outras temáticas surgiram nos encontros formações (que não se pretendiam engessados e não objetivavam a paralisação dos fluxos que pedem passagem), e tais assuntos puderam ser usados como disparadores para criação de outros movimentos curriculares; as concepções dos professores sobre a “dificuldade/facilidade” em ministrar aulas para o Proeja e os lugares estabelecidos entre estudantes e docentes no processo ensino-aprendizagem não estão relacionados diretamente, em relação de causa e efeito, à disciplina/área de conhecimento específica que ministram, mas aos agenciamentos, aos ligamentos e às rupturas produzidas nas relações com essas redes de saberes fazeres poderes que envolvem múltiplos agentes: docentes, outros servidores, alunos, experiências e encontros múltiplos dentro fora no espaço tempo do Ifes; uma tríade-refrão coopera para a criação de uma fôrma triangular que enfatiza a noção de um padrão em um processo molar enraizado nas árvores do conhecimento: perfil, seleção e nivelamento, contudo, algumas linhas de fuga dissonantes são criadas por entre as fissuras dos pretensos tons harmônicos; as frases “os professores do IF não estão preparados para ministrar aulas para o Proeja” ou “não há formação/qualificação para os docentes se relacionarem com o Proeja” são utilizadas, em alguns discursos, como escudos-argumentos para a opção-política de não oferta de vagas para a modalidade EJA em composição com fios que afirmam tal especificidade da educação básica, dentro da rede federal, como um “favor social”; processos que envolvem a (des)organização da matriz curricular são considerados por alguns participantes como início, “produto” e objetivo das conversas curriculares e provocam tensões que (i)mobilizam, (não) movimentam entre os afetos dos corpos, podendo levar à (não) ação coletiva; a noção de “mercado de trabalho” ainda impera nos discursos, ciclicamente, enquanto início fim das problematizações do currículo do Ensino Médio e da EJA; a expressão “integração curricular” é constantemente usada nos discursos que circulam o campus, no entanto, os sentidos produzidos, as concepções e as teorias curriculares que embasam a noção de “integração” no currículo são bem diversos; não há totalidades nos discursos, não há homogeneização, não foi efetivada nenhuma coesão/única voz representante (e esse também não era o objetivo desta pesquisa); ainda que o tema da roda se propusesse às conversas curriculares do/no Proeja, nesses encontros, os participantes manifestaram a necessidade de intensificar os movimentos produzidos nas rodas visando à discussão dos currículos textos de todos os cursos e modalidades ofertados pelos campus VNI e na intensificação de espaços para trocas de experiências curriculares cotidianas; na potencialização das diferenças como possibilidades de inventividade nos encontros-formações docente e nas danças curriculares que envolvem diversas relações de aprendizagem no Ifes, algumas experimentações foram produzidas, entre afetos, criando composições(des)(re)territorializantes e ressonando com movimentos que não se restringiram às rodas de conversas, contudo, enredaram-se em fios de outros espaços tempos do campus em tentativas de propagações de currículos multidão.
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A rede mundial de computadores (Internet) é, atualmente, fonte de informação sobre saúde para leigos e profissionais da área médica. A Rinite Alérgica é uma doença muito prevalente que chega a atingir mais de 10% da população geral, causando queda da qualidade de vida. OBJETIVO: Avaliar os princípios éticos de sites brasileiros que divulgam informações a respeito do tema "rinite alérgica". FORMA DE ESTUDO: revisional. MATERIAL E MÉTODO: Foi feita avaliação de 173 sites brasileiros encontrados através de quatro mecanismos de busca (Google, Yahoo, Altavista e Radar Uol). Os sites foram avaliados de acordo com o Manual de Princípios Éticos para Sites de Medicina e Saúde do CREMESP (Conselho Regional de Medicina do Estado de São Paulo), de acordo com os itens transparência, honestidade, qualidade, consentimento livre e esclarecido, privacidade, ética médica, responsabilidade e procedência. RESULTADOS: Entre os sites analisados, 149 (86,1%) não estavam de acordo como Manual de Princípios Éticos para Sites de Medicina e Saúde do CREMESP. As proporções de irregularidades entre os itens avaliados foram: qualidade (84,4%), privacidade (46,2%) honestidade (18,5%), consentimento livre e esclarecido (15,6%), responsabilidade (13,9%), transparência (12,1%), ética médica (2,3%). Havia informações inexatas em 24,3% dos sites analisados. CONCLUSÕES: A maioria dos sites estudados contendo informações sobre rinite alérgica fere os princípios éticos para sites do CREMESP. Tanto a qualidade em geral de grande parte dos sites brasileiros que abordam o tema "rinite alérgica", quanto à qualidade das informações por eles divulgadas, são insuficientes para satisfazer a médicos e pacientes.