207 research outputs found
Measurement of the Ge 70 (n,γ) cross section up to 300 keV at the CERN n-TOF facility
©2019 American Physical Society.Neutron capture data on intermediate mass nuclei are of key importance to nucleosynthesis in the weak component of the slow neutron capture processes, which occurs in massive stars. The (n,γ) cross section on Ge70, which is mainly produced in the s process, was measured at the neutron time-of-flight facility n-TOF at CERN. Resonance capture kernels were determined up to 40 keV neutron energy and average cross sections up to 300 keV. Stellar cross sections were calculated from kT=5 keV to kT=100 keV and are in very good agreement with a previous measurement by Walter and Beer (1985) and recent evaluations. Average cross sections are in agreement with Walter and Beer (1985) over most of the neutron energy range covered, while they are systematically smaller for neutron energies above 150 keV. We have calculated isotopic abundances produced in s-process environments in a 25 solar mass star for two initial metallicities (below solar and close to solar). While the low metallicity model reproduces best the solar system germanium isotopic abundances, the close to solar model shows a good global match to solar system abundances in the range of mass numbers A=60-80.Peer reviewedFinal Published versio
Ticks (Acari: Ixodidae) associated with small terrestrial mammals in the state of Minas Gerais, southeastern Brazil
From June 2005 to November 2010, 43 small mammals encompassing 6 species of Didelphimorphia, 8 species of Rodentia, and 1 species of Lagomorpha were found parasitized by ticks in the state of Minas Gerais, southeastern Brazil. Nine tick species, in total 186 specimens, were identified as follows: Amblyomma cajennense (larvae and nymphs) on opossums and rodents; Amblyomma ovale (nymphs) on rodents; Amblyomma parvum (nymphs) on rodents; Amblyomma coelebs (nymphs) on opossums; Amblyomma dubitatum (nymph) on opossums; Ixodes amarali (females, nymphs, and larvae) on opossums and rodents; Ixodes loricatus (male, females, nymph) on opossums; Ixodes schulzei (female) on rodents; and Haemaphysalis leporispalustris (female) on rabbits. Most of the tick-host associations found in the present study have never been recorded in the literature; those include three new host records for I. amarali, four for A. cajennense, one for A. dubitatum, two for A. ovale, and one for A. coelebs. In addition, we provide the first record of A. coelebs in the state of Minas Gerais.CNPq (Brazil)FAPESP (Brazil)INTA (Argentina)CONICET (Argentina)Asociacion Cooperadora de la EEA-INTA Rafaela (Argentina
Sampling strategies to estimate suspended sediment concentration for turbidimeter calibration
ASPECTOS EPIDEMIOLÓGICOS E PREVALÊNCIA DE ENTEROPARASITOSES EM CRIANÇAS DO BAIRRO JAMBEIRO, SÃO LUÍS, MA
A carência de condições básicas de higiene e saneamento, aliadas à falta de limpeza dos reservatórios de água e a não utilização de água fltrada ou fervida, intensifcam a ocorrência de problemas de saúde pública. Com o intuito de contribuir para a conscientização da população acerca dos problemas de saúde decorrentes da contaminação da água, realizou-se no Bairro do Jambeiro, localizado nas mediações da Universidade Federal do Maranhão, um projeto interdisciplinar que visou, pela divulgação dos dados da pesquisa científca, avaliar a água utilizada pelos moradores através de análise físico-química, microbiológica e parasitológica, de modo que os resultados permitissem a conscientização, através de atividades educacionais dos moradores. Os resultados endossam a precariedade de condições sanitárias encontradas nessa comunidade. Os poços, as torneiras e o córrego apresentam níveis de contaminação acima do recomendável pela Resolução CONAMA e ANVISA, sendo, portanto, impróprias para o consumo. Os exames parasitológicos revelaram alta prevalência (91%) de enteroparasitoses nas crianças. A partir desses resultados os integrantes do projeto e seus parceiros realizaram palestras destinadas à comunidade sobre os meios de tratamento da água, biologia dos parasitas e medidas profláticas das principais verminoses. Concomitante, ocorreu a entrega e esclarecimentos dos laudos da análise físico-química, microbiológica e parasitológica, onde houve a distribuição de remédios às crianças que estavam infectadas.Descritores: Enteroparasitos; Epidemiologia; Prevalência.Abstract: The lack of basic conditions hygiene and sanitation, allied to grubbiness of water reservoirs and no use of fltered or boiled water, enhance the occurrence of health public problems. With the aim of contribute to awareness of the population about the health problems resulting from the water contamination, was held in the District of the Jambeiro, located near the Federal University of Maranhão, an interdisciplinary project the aimed, by disclosure of scientifc research, to evaluate the water used by population through physico-chemical, microbiological and parasitological analyses, so that the results allow awareness through educational activities of population. The results comproved the precarious sanitary conditions found in this community. The level contamination of the wells, taps and stream is higher than recommended by Resolution CONAMA and ANVISA, therefore, unft for consumption. The parasitological revealed a high prevalence (91%) of intestinal parasites in children. Based on these results the members of the project and its partners held talks for the community about the water treatment, biology of parasites and worms and of the main prophylactic measures. Concomitantly, there was the delivery and clarifcation of reports of physico-chemical, microbiological and parasitological, where there was the distribution of drugs to children who were infected.Descriptors: Enteroparasites; Epidemiology; Prevalence
Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli
Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins. Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets
Evolutionary Analyses of Entire Genomes Do Not Support the Association of mtDNA Mutations with Ras/MAPK Pathway Syndromes
BACKGROUND: There are several known autosomal genes responsible for Ras/MAPK pathway syndromes, including Noonan syndrome (NS) and related disorders (such as LEOPARD, neurofibromatosis type 1), although mutations of these genes do not explain all cases. Due to the important role played by the mitochondrion in the energetic metabolism of cardiac muscle, it was recently proposed that variation in the mitochondrial DNA (mtDNA) genome could be a risk factor in the Noonan phenotype and in hypertrophic cardiomyopathy (HCM), which is a common clinical feature in Ras/MAPK pathway syndromes. In order to test these hypotheses, we sequenced entire mtDNA genomes in the largest series of patients suffering from Ras/MAPK pathway syndromes analyzed to date (n = 45), most of them classified as NS patients (n = 42). METHODS/PRINCIPAL FINDINGS: The results indicate that the observed mtDNA lineages were mostly of European ancestry, reproducing in a nutshell the expected haplogroup (hg) patterns of a typical Iberian dataset (including hgs H, T, J, and U). Three new branches of the mtDNA phylogeny (H1j1, U5b1e, and L2a5) are described for the first time, but none of these are likely to be related to NS or Ras/MAPK pathway syndromes when observed under an evolutionary perspective. Patterns of variation in tRNA and protein genes, as well as redundant, private and heteroplasmic variants, in the mtDNA genomes of patients were as expected when compared with the patterns inferred from a worldwide mtDNA phylogeny based on more than 8700 entire genomes. Moreover, most of the mtDNA variants found in patients had already been reported in healthy individuals and constitute common polymorphisms in human population groups. CONCLUSIONS/SIGNIFICANCE: As a whole, the observed mtDNA genome variation in the NS patients was difficult to reconcile with previous findings that indicated a pathogenic role of mtDNA variants in NS
Intimate partner violence among undergraduate students of two universities of the state of São Paulo, Brazil
Cultivo mínimo: efeito da compactação e deformação abaixo da atuação da ponteira do subsolador
Studies on cambial activity: advances and challenges in the knowledge of growth dynamics of Brazilian woody species
Environmentalism in the EU-28 context: the impact of governance quality on environmental energy efficiency
Environmental policies are a significant cornerstone of a developed economy, but the question that arises is whether such policies lead to a sustainable growth path. It is clear that the energy sector plays a pivotal role in environmental policies, and although the current literature has focused on examining the link between energy consumption and economic growth through an abundance of studies, it does not explicitly consider the role of institutional or governance quality variables in the process. Both globalization and democracy are important drivers of sustainability, while environmentalism is essential for the objective of gaining a “better world.” Governance quality is expected to be the key, not only for economic purposes but also for the efficiency of environmental policies. To that end, the analysis in this paper explores the link between governance quality and energy efficiency for the EU-28 countries, spanning the period 1995 to 2014. The findings document that there is a nexus between energy efficiency and income they move together: the most efficient countries are in the group with higher GDP per capita. Furthermore, the results show that governance quality is an important driver of energy efficiency and, hence, of environmental policies.University of Granad
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