918 resultados para Strain I-2


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The rise in population growth, as well as nutrient mining, has contributed to low agricultural productivity in Sub-Saharan Africa (SSA). A plethora of technologies to boost agricultural production have been developed but the dissemination of these agricultural innovations and subsequent uptake by smallholder farmers has remained a challenge. Scientists and philanthropists have adopted the Integrated Soil Fertility Management (ISFM) paradigm as a means to promote sustainable intensification of African farming systems. This comparative study aimed: 1) To assess the efficacy of Agricultural Knowledge and Innovation Systems (AKIS) in East (Kenya) and West (Ghana) Africa in the communication and dissemination of ISFM (Study I); 2) To investigate how specifically soil quality, and more broadly socio-economic status and institutional factors, influence farmer adoption of ISFM (Study II); and 3) To assess the effect of ISFM on maize yield and total household income of smallholder farmers (Study III). To address these aims, a mixed methodology approach was employed for study I. AKIS actors were subjected to social network analysis methods and in-depth interviews. Structured questionnaires were administered to 285 farming households in Tamale and 300 households in Kakamega selected using a stratified random sampling approach. There was a positive relationship between complete ISFM awareness among farmers and weak knowledge ties to both formal and informal actors at both research locations. The Kakamega AKIS revealed a relationship between complete ISFM awareness among farmers and them having strong knowledge ties to formal actors implying that further integration of formal actors with farmers’ local knowledge is crucial for the agricultural development progress. The structured questionnaire was also utilized to answer the query pertaining to study II. Soil samples (0-20 cm depth) were drawn from 322 (Tamale, Ghana) and 459 (Kakamega, Kenya) maize plots and analysed non-destructively for various soil fertility indicators. Ordinal regression modeling was applied to assess the cumulative adoption of ISFM. According to model estimates, soil carbon seemed to preclude farmers from intensifying input use in Tamale, whereas in Kakamega it spurred complete adoption. This varied response by farmers to soil quality conditions is multifaceted. From the Tamale perspective, it is consistent with farmers’ tendency to judiciously allocate scarce resources. Viewed from the Kakamega perspective, it points to a need for farmers here to intensify agricultural production in order to foster food security. In Kakamega, farmers with more acidic soils were more likely to adopt ISFM. Other household and farm-level factors necessary for ISFM adoption included off-farm income, livestock ownership, farmer associations, and market inter-linkages. Finally, in study III a counterfactual model was used to calculate the difference in outcomes (yield and household income) of the treatment (ISFM adoption) in order to estimate causal effects of ISFM adoption. Adoption of ISFM contributed to a yield increase of 16% in both Tamale and Kakamega. The innovation affected total household income only in Tamale, where ISFM adopters had an income gain of 20%. This may be attributable to the different policy contexts under which the two sets of farmers operate. The main recommendations underscored the need to: (1) improve the functioning of AKIS, (2) enhance farmer access to hybrid maize seed and credit, (3) and conduct additional multi-locational studies as farmers operate under varying contexts.

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Introdução: As doenças cardiovasculares são a principal cauda de mortalidade em Portugal e na maioria dos países desenvolvidos. Uma reflexão sobre esta temática entra em acordo com a perspetiva de Ski et al. (2011); Shirato e Swan (2010) e Fogel e Wood (2008), em que estudo das doenças cardiovasculares durante muito tempo, foi mais direcionado para o homem, pelo que a investigação no género feminino se revela recente e ainda com algumas fragilidades. De acordo com WHO (2011), há evidências de que a mesma é subdetectada em mulheres e que há atrasos no diagnóstico e tratamento invasivo em relação aos homens. Neste domínio, é imprescindível um olhar mais atento e com uma perspetiva mais complexa sobre a mulher. A reforçar a pertinência de um estudo sobre a mulher neste domínio, Ferreira (2012), num estudo sobre a evolução temporal dos fatores de risco cardiovascular na população portuguesa, revela a presença de desigualdades de género, evidenciando que a mulher representa uma tendência crescente para a sua prevalência. Por sua vez, WHO (2013) evidencia um dos principais fatores de risco para a doença cardiovascular é a hipertensão, que assume um lugar de destaque, uma vez que já afeta um bilhão de pessoas em todo o mundo, sendo mesmo considerada como um assassino invisível e silencioso que raramente causa sintomas. Objetivos Conhecer e analisar o risco a curto prazo de Hipertensão Arterial das mulheres para 1, 2 e 4 anos; Analisar fatores sociodemográficos e correlacioná-los com o risco de com o risco de desenvolver HTA a 1,2 e 4 anos. Analisar os hábitos alimentares, perfil antropométrico e somatotipo das mulheres e correlacionar com o risco de desenvolver HTA a 1,2 e 4 anos. Comparar o risco de hipertensão arterial na mulher da região centro entre o meio rural e urbano. Analisar o nível de conhecimento sobre a hipertensão arterial e correlacionar com o risco de desenvolver HTA a 1,2 e 4 anos. Metodologia Estudo quantitativo, exploratório e descritivo-correlacional com objetivo de descrever os fatores preditores para o risco de desenvolver HTA a 1, 2 e 4 anos. A amostra é constituída por 406 mulheres dos 20 aos 69 anos, residentes na região centro. Instrumento de recolha de dados: Caracterização sociodemográfica; avaliação antropométrica (inclui 17 medições divididas em cinco categorias: medidas básicas (peso e altura), pregas cutâneas, perímetros, larguras e diâmetros, o registo destas avaliações, permite a aplicação de diferentes equações que determinam, entre outros, a composição corporal e o somatotipo); cálculo do risco de HTA; escala de hábitos alimentares e teste de batalha. O tratamento estatístico foi realizado informaticamente com o programa de SPSS (Statistical Package for the Social Science) versão 2.0. O tamanho da amostra foi efetuada através do cálculo da OpenEpi, que é um programa gratuito e de código aberto para estatísticas epidemiológicas para a Saúde Pública, encontrando-se acessível no site: http://www.openepi.com/v37/Menu/OE_Menu.htm. Foi utilizada a versão 3.01, atualizada em 6/04/2013. De acordo com dados do INE, na região centro residem 767583 mulheres entre os grupos etários 20-69 anos de idade, no ano de 2012 (último ano com dados publicados). Assim, o tamanho da amostra com um intervalo de confiança de 95%, não pode ser inferior a 384 mulheres. Procedimentos Éticos: Comissão ética da ESEnfC; Consentimento informado e esclarecido a todas as participantes e às instituições/locais de recolha de informação. Resultados: A amostra é constituída por 406 mulheres residentes na região centro, que apresentam uma idade mínima de 20 anos e máxima de 69, média de 42,3 anos. Nível de escolaridade, das 406 mulheres da amostra,15,8 % possuem o 1º ciclo, 12,6% o 2º ciclo, 17,2% 3º ciclo, 34,2%, o nível secundário, 1,7% Bacharelato,15,3% Licenciatura, 2,5% Mestrado e 0,7 % Doutoramento. Maioritariamente são casadas (57,9%), seguidamente solteiras (20,4%), divorciadas (10,8%), em união de facto (5,7 %) e, por fim, viúvas (5,2%), sendo que 200 mulheres residem em meio rural e 206 mulheres em meio urbano. Nas classes de Índice de Massa Corporal (IMC), verifica-se que 1,7 % das mulheres têm baixo peso, 42,4 % apresentam peso normal, 35,5 % têm sobrepeso, 13,3 % Obesidade grau I, 5,9% Obesidade grau II e 1,2% Obesidade grau III. Assim 55,9% das mulheres apresentam elevado IMC, o que revela peso superior ao normal, sendo que 50,5% tendem a ser endomorfas, 45,5 % mesomorfas e apenas 3% tendem a ser ectomorfas. 43,6% das mulheres da região centro apresentam Tensão Arterial(TA) ótima, 30,3 % TA dentro de parâmetros normais, 13,79% com a classificação Normal Alta, 9,61% HTA nível I, 2,27% % HTA nível II e 0,5 % HTA nível III. 45,81% não têm Ascendentes diretos com HTA, 39,41% um e 14,78% dois ascendentes diretos com HTA. De uma forma mais pormenorizada, observámos que na realidade mais de metade da amostra, nomeadamente 54,14 % das mulheres apresenta um ou dois ascendentes diretos com HTA. Relativamente ao risco de desenvolver HTA a 1 ano, constata-se que 88,2 % das mulheres apresenta de 0 - 25 % de risco, e contrariamente, apenas 4,9 % apresentam de 75- 100% de risco. Contudo, no que refere ao risco de desenvolver HTA em 4 anos; 66,5 % das mulheres apresentam de 0- 25% de risco e 11,6% apresentam de 75-100% de risco. Analisaram-se as respostas do teste de Batalha - conhecimento sobre a doença, verifica-se que apenas 49,5 % da totalidade da amostra responderam acertadamente às três questões, pelo que podemos inferir que nível de conhecimento sobre a HTA é baixo. 37,4% respondeu acertadamente a duas questões, 10,6% a uma questão, e apenas 2,5% não conseguiu cumprir o teste, apresentando zero respostas certas. Os resultados relativos aos hábitos alimentares das mulheres da região centro, de acordo a aplicação da Escala de hábitos alimentares, podemos verificar que a média foi 97,57, sendo de salientar que o valor da escala mais baixo encontrado foi de 58 e máximo 140. Importa ainda evidenciar que nenhuma mulher atingiu o score máximo. Considera-se que quanto mais elevada for a pontuação média de todos os itens, mais adequados serão os hábitos alimentares. Nesta conformidade, e considerando que a escala tem valores entre o e 180, podemos inferir que as mulheres constituintes da amostra apresentam hábitos alimentares são pouco satisfatórios. Discussão / Conclusões A realização desta investigação permitiu-nos concluir que as mulheres da região centro de Portugal apresentam um significativo risco de desenvolver Hipertensão Arterial a 1, 2 e 4 anos, existindo um conjunto de fatores que influencia positiva ou negativamente este resultado. Deste modo, constatamos que as mulheres com mais idade, viúvas ou casadas, residentes em meio rural, inativas profissionalmente, fumadoras e com conhecimento sobre a HTA, são as que apresentam maior risco de Desenvolver HTA a 1, 2 e 4 anos. Contrariamente, as mulheres com peso normal ou baixo peso, de composição corporal com tendência a ser mais ectomorfa e com TA óptima ou normal, revelaram baixo risco de desenvolver HTA a 1, 2 e 4 anos. Apesar de os hábitos alimentares serem pouco satisfatórios, não se verificou evidência estatísticas de que os mesmos influenciam o risco de desenvolver HTA a 1,2 e 4 anos. Verificamos na análise inferencial que, a idade, escolaridade, o emprego, o IMC e a Classificação de Tensão Arterial são os principais fatores preditores para o desenvolvimento de HTA. Nesta acepção, concluímos que este estudo é um excelente contributo para a efetividade de estratégias de prevenção, desde o planeamento até à fase de implementação, na medida em que permite identificar fatores preditivos e definir grupos de risco para o desenvolvimento HTA. Consideramos por isso que os nossos resultados são satisfatórios e coadjuvantes com as metas lançadas pela WHO (2013), para atingir até 2025 nomeadamente: redução de 25% nas taxas de mortalidade global por doenças cardiovasculares e redução de 25% na prevalência de pressão arterial elevada na população. Concluímos assim, à semelhança da opinião de Marques e Serra (2012) que é urgente e necessário identificar subgrupos de risco e aplicar scores de risco para melhor decisão das necessidades de intervenção. Por outro lado, identificar e compreender quais os fatores de risco que influenciam o risco de desenvolver HTA a 1,2 e 4 anos, é com certeza uma mais-valia para as etapas de prevenção e redução da incidência de HTA.

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Edwardsiella tarda is a bacterial pathogen that can infect both humans and animals. TX1, an Ed. tarda strain isolated from diseased fish, was found to produce autoinducer 2 (Al-2)-like activity that was growth phase dependent and modulated by growth conditions. The gene coding for the Al-2 synthase was cloned from TX1 and designated luxS(Et). LuxS(Et) was able to complement the Al-2 mutant phenotype of Escherichia coli strain DH5 alpha. Expression Of luxS(Et) correlated with Al-2 activity and was increased by glucose and decreased by elevated temperature. The effect of glucose was shown to be mediated through the cAMP-CRP complex, which repressed luxS(Et) expression. Overexpression of luxS(Et) enhanced Al-2 activity in TX1, whereas disruption of luxS(Et) expression by antisense RNA interference (i) reduced the level of Al-2 activity, (ii) impaired bacterial growth under various conditions, (iii) weakened the expression of genes associated with the type III secretion system and biofilm formation, and (iv) attenuated bacterial virulence. Addition of exogenous Al-2 was able to complement the deficiencies in the expression of TTSS genes and biofilm production but failed to rescue the growth defects. Our results (i) demonstrated that the Al-2 activity in TX1 is controlled at least in part at the level of luxS(Et) expression, which in turn is regulated by growth conditions, and that the temporal expression of luxS(Et) is essential for optimal bacterial infection and survival; and (ii) suggested the existence in Ed. tarda of a LuxS/Al-2-mediated signal transduction pathway that regulates the production of virulence-associated elements.

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Edwardsiella tarda is a bacterial pathogen that can infect both humans and animals. TX1, an Ed. tarda strain isolated from diseased fish, was found to produce autoinducer 2 (Al-2)-like activity that was growth phase dependent and modulated by growth conditions. The gene coding for the Al-2 synthase was cloned from TX1 and designated luxS(Et). LuxS(Et) was able to complement the Al-2 mutant phenotype of Escherichia coli strain DH5 alpha. Expression Of luxS(Et) correlated with Al-2 activity and was increased by glucose and decreased by elevated temperature. The effect of glucose was shown to be mediated through the cAMP-CRP complex, which repressed luxS(Et) expression. Overexpression of luxS(Et) enhanced Al-2 activity in TX1, whereas disruption of luxS(Et) expression by antisense RNA interference (i) reduced the level of Al-2 activity, (ii) impaired bacterial growth under various conditions, (iii) weakened the expression of genes associated with the type III secretion system and biofilm formation, and (iv) attenuated bacterial virulence. Addition of exogenous Al-2 was able to complement the deficiencies in the expression of TTSS genes and biofilm production but failed to rescue the growth defects. Our results (i) demonstrated that the Al-2 activity in TX1 is controlled at least in part at the level of luxS(Et) expression, which in turn is regulated by growth conditions, and that the temporal expression of luxS(Et) is essential for optimal bacterial infection and survival; and (ii) suggested the existence in Ed. tarda of a LuxS/Al-2-mediated signal transduction pathway that regulates the production of virulence-associated elements.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Both P-i-repressible acid phosphatases, IIb (mycelial) and IIc (extracellular), synthesized by Neurospora crassa and purified to apparent homogeneity by 7.5% PAGE, are monomers, are inhibited by 2 mM ZnCl2 and are nonspecifically stimulated by salts. However, the IIc form is activated by p-nitrophenylphosphate (in a negative cooperativity effect with a K-0.5 of 2.5 mM) whereas form IIb shows Michaelis kinetics, with a K-m of 0.5 mM. Thus, since both enzymatic forms may be expressed by the same gene (pho-3), it is possible that post-translational modifications lead to the excretion of an enzymatic form with altered Michaelis kinetics compared with the enzymatic form retained by the mycelium.

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It has been reported that fetal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes defects in the male reproductive system of the rat. We set out to replicate and extend these effects using a robust experimental design. Groups of 75 (control vehicle) or 55 (50, 200 or 1000 ng of TCDD kg-1 bodyweight) female Wistar(Han) rats were exposed to TCDD on Gestational Day (GD) 15, then allowed to litter. The high dose group dams showed no sustained weight loss compared to control, but four animals had total litter loss. Pups in the high dose group showed reduced body weight up till day 21, and pups in the medium dose group showed reduced body weight in the first week post partum. Balano-preputial separation (BPS) was significantly delayed in the high dose group male offspring. There were no significant effects of treatment when the offspring were subjected to a functional observational battery, or mated with females to assess reproductive capability. 25 males per group were killed on post natal day (PND) 70, and ~60 animals per group (~30 for the high dose group) on PND120 to assess seminology and other endpoints. At PND120, the two highest dose groups showed a statistically significant elevation of sperm counts, compared to control; however, this effect was small (~30%), within the normal range of sperm counts for this strain of rat, was not reflected in testicular spermatid counts nor PND70 data, and is therefore postulated to have no biological significance. Although there was an increase in the proportion of abnormal sperm at PND70, seminology parameters were otherwise unremarkable. Testis weights in the high dose group were slightly decreased at PND 70 and 120, and at PND120, brain weights were decreased in the high dose group, liver to body weight ratios were increased for all three dose groups, with an increase in inflammatory cell foci in the epididymis in the high dose group. These data show that TCDD is a potent developmental toxin after exposure of the developing fetus, but that acute developmental exposure to TCDD on GD15 caused no decrease in sperm counts.

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A marked increase in the prevalence of S. enterica serovar 4,[5],12:i:- with resistance to ampicillin, streptomycin, sulphonamides and tetracyclines (R-type ASSuT) has been noted in food-borne infections and in pigs/pig meat in several European countries in the last ten years. One hundred and sixteen strains of S. enterica serovar 4,[5],12:i:- from humans, pigs and pig meat isolated in England and Wales, France, Germany, Italy, Poland, Spain and the Netherlands were further subtyped by phage typing, pulsed-field gel electrophoresis and multilocus variable number tandem repeat analysis to investigate the genetic relationship among strains. PCR was performed to identify the fljB flagellar gene and the genes encoding resistance to ampicillin, streptomycin, sulphonamides and tetracyclines. Class 1 and 2 integrase genes were also sought. Results indicate that genetically related serovar 4,[5],12:i:- strains of definitive phage types DT193 and DT120 with ampicillin, streptomycin, sulphonamide and tetracycline resistance encoded by blaTEM, strA-strB, sul2 and tet(B) have emerged in several European countries, with pigs the likely reservoir of infection. Control measures are urgently needed to reduce spread of infection to humans via the food chain and thereby prevent the possible pandemic spread of serovar 4,[5],12:i:- of R-type ASSuT as occurred with S. Typhimurium DT104 during the 1990s.

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Chlamydia pneumoniae is a common human and animal pathogen associated with a wide range of upper and lower respiratory tract infections. In more recent years there has been increasing evidence to suggest a link between C. pneumoniae and chronic diseases in humans, including atherosclerosis, stroke and Alzheimer’s disease. C. pneumoniae human strains show little genetic variation, indicating that the human-derived strain originated from a common ancestor in the recent past. Despite extensive information on the genetics and morphology processes of the human strain, knowledge concerning many other hosts (including marsupials, amphibians, reptiles and equines) remains virtually unexplored. The koala (Phascolarctos cinereus) is a native Australian marsupial under threat due to habitat loss, predation and disease. Koalas are very susceptible to chlamydial infections, most commonly affecting the conjunctiva, urogenital tract and/or respiratory tract. To address this gap in the literature, the present study (i) provides a detailed description of the morphologic and genomic architecture of the C. pneumoniae koala (and human) strain, and shows that the koala strain is microscopically, developmentally and genetically distinct from the C. pneumoniae human strain, and (ii) examines the genetic relationship of geographically diverse C. pneumoniae isolates from human, marsupial, amphibian, reptilian and equine hosts, and identifies two distinct lineages that have arisen from animal-to-human cross species transmissions. Chapter One of this thesis explores the scientific problem and aims of this study, while Chapter Two provides a detailed literature review of the background in this field of work. Chapter Three, the first results chapter, describes the morphology and developmental stages of C. pneumoniae koala isolate LPCoLN, as revealed by fluorescence and transmission electron microscopy. The profile of this isolate, when cultured in HEp-2 human epithelial cells, was quite different to the human AR39 isolate. Koala LPCoLN inclusions were larger; the elementary bodies did not have the characteristic pear-shaped appearance, and the developmental cycle was completed within a shorter period of time (as confirmed by quantitative real-time PCR). These in vitro findings might reflect biological differences between koala LPCoLN and human AR39 in vivo. Chapter Four describes the complete genome sequence of the koala respiratory pathogen, C. pneumoniae LPCoLN. This is the first animal isolate of C. pneumoniae to be fully-sequenced. The genome sequence provides new insights into genomic ‘plasticity’ (organisation), evolution and biology of koala LPCoLN, relative to four complete C. pneumoniae human genomes (AR39, CWL029, J138 and TW183). Koala LPCoLN contains a plasmid that is not shared with any of the human isolates, there is evidence of gene loss in nucleotide salvage pathways, and there are 10 hot spot genomic regions of variation that were previously not identified in the C. pneumoniae human genomes. Sequence (partial-length) from a second, independent, wild koala isolate (EBB) at several gene loci confirmed that the koala LPCoLN isolate was representative of a koala C. pneumoniae strain. The combined sequence data provides evidence that the C. pneumoniae animal (koala LPCoLN) genome is ancestral to the C. pneumoniae human genomes and that human infections may have originated from zoonotic infections. Chapter Five examines key genome components of the five C. pneumoniae genomes in more detail. This analysis reveals genomic features that are shared by and/or contribute to the broad ecological adaptability and evolution of C. pneumoniae. This analysis resulted in the identification of 65 gene sequences for further analysis of intraspecific variation, and revealed some interesting differences, including fragmentation, truncation and gene decay (loss of redundant ancestral traits). This study provides valuable insights into metabolic diversity, adaptation and evolution of C. pneumoniae. Chapter Six utilises a subset of 23 target genes identified from the previous genomic comparisons and makes a significant contribution to our understanding of genetic variability among C. pneumoniae human (11) and animal (6 amphibian, 5 reptilian, 1 equine and 7 marsupial hosts) isolates. It has been shown that the animal isolates are genetically diverse, unlike the human isolates that are virtually clonal. More convincing evidence that C. pneumoniae originated in animals and recently (in the last few hundred thousand years) crossed host species to infect humans is provided in this study. It is proposed that two animal-to-human cross species events have occurred in the context of the results, one evident by the nearly clonal human genotype circulating in the world today, and the other by a more animal-like genotype apparent in Indigenous Australians. Taken together, these data indicate that the C. pneumoniae koala LPCoLN isolate has morphologic and genomic characteristics that are distinct from the human isolates. These differences may affect the survival and activity of the C. pneumoniae koala pathogen in its natural host, in vivo. This study, by utilising the genetic diversity of C. pneumoniae, identified new genetic markers for distinguishing human and animal isolates. However, not all C. pneumoniae isolates were genetically diverse; in fact, several isolates were highly conserved, if not identical in sequence (i.e. Australian marsupials) emphasising that at some stage in the evolution of this pathogen, there has been an adaptation/s to a particular host, providing some stability in the genome. The outcomes of this study by experimental and bioinformatic approaches have significantly enhanced our knowledge of the biology of this pathogen and will advance opportunities for the investigation of novel vaccine targets, antimicrobial therapy, or blocking of pathogenic pathways.

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Dengue fever is the most important mosquito-borne viral disease of humans with more than 50 million cases estimated annually in more than 100 countries. Disturbingly, the geographic range of dengue is currently expanding and the severity of outbreaks is increasing. Control options for dengue are very limited and currently focus on reducing population abundance of the major mosquito vector, Aedes aegypti. These strategies are failing to reduce dengue incidence in tropical communities and there is an urgent need for effective alternatives. It has been proposed that endosymbiotic bacterial Wolbachia infections of insects might be used in novel strategies for dengue control. For example, the wMelPop-CLA Wolbachia strain reduces the lifespan of adult A. aegypti mosquitoes in stably transinfected lines. This life-shortening phenotype was predicted to reduce the potential for dengue transmission. The recent discovery that several Wolbachia infections, including wMelPop-CLA, can also directly influence the susceptibility of insects to infection with a range of insect and human pathogens has markedly changed the potential for Wolbachia infections to control human diseases. Here we describe the successful transinfection of A. aegypti with the avirulent wMel strain of Wolbachia, which induces the reproductive phenotype cytoplasmic incompatibility with minimal apparent fitness costs and high maternal transmission, providing optimal phenotypic effects for invasion. Under semi-field conditions, the wMel strain increased from an initial starting frequency of 0.65 to near fixation within a few generations, invading A. aegypti populations at an accelerated rate relative to trials with the wMelPop-CLA strain. We also show that wMel and wMelPop-CLA strains block transmission of dengue serotype 2 (DENV-2) in A. aegypti, forming the basis of a practical approach to dengue suppression.

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Bi-2212 tapes were fabricated using a powder-in-tube method and their superconducting properties were measured as a function of heat treatment. The tapes were heated to temperature, T1 (884-915 °C), and kept at that temperature for 20 min to induce partial (incongruent) melting. The samples were cooled to T2 with a ramp rate of 120 °C h-1 and then slowly cooled to T3 with a cooling rate, R2, and from T3 to T4 with a cooling rate, R3. The tapes were kept at the temperature T4 for P1 hours and then cooled to room temperature. Both R1 and R2 were chosen between 2 and 8 °C h-1. It was found that the structure and Jc of the tapes depend on the sintering conditions, i.e. T1-4, R1-3 and P1. The highest Jc of 5800 Å cm-2 was obtained at 77 K in a self-field with heat treatment where T1 = 894 and 899 °C, R1 = R2 = 5 °C h-1 and P1 = 6 h were employed. When 0.7% of bend strain, which is equivalent to a bend radius of 5 mm, was applied to the tape, 80% of the initial Jc was sustained.