66 research outputs found
Desenvolvimento de leguminosas herbáceas perenes, semeadas na época das águas no sul do Tocantins.
O objetivo deste trabalho foi avaliar o desenvolvimento de leguminosas herbáceas perenes semeadas na época das águas no sul do Tocantins, onde foram utilizadas: cudzu tropical (Pueraria phaseoloides), siratro (Macroptilium atropurpureum) e centrosema (Centrosema pubescens). O estudo foi conduzido na Universidade Federal do Tocantins, no município de Gurupi-TO, com delineamento experimental em blocos casualizados com quatro repetições avaliando: velocidade de emergência; capacidade de cobertura do solo; supressão sobre as plantas invasoras; decomposição e acúmulo de nutrientes na parte aérea. O siratro apresentou maior velocidade de emergência, enquanto o cudzu tropical obteve crescimento mais lento, porém reduziu maior número de plantas invasoras. Não foi observada diferença significativa entre os tratamentos na decomposição dos resíduos. A centrosema proporcionou maior aporte de N e P, e quanto aos demais macronutrientes, não foi observada diferença estatística
CARACTERIZAÇÃO FÍSICO-QUÍMICA DE MÉIS PRODUZIDOS NO ESTADO DE MATO GROSSO DO SUL, BRASIL
O trabalho foi desenvolvido com o objetivo de caracterizar, através de análises físico-químicas, nove amostras de méis oriundas de apiários localizados nos municípios de Cassilândia, Aquidauana e Campo Grande, MS. As amostras foram levadas ao laboratório de análises de alimento da UFMS para determinação dos índices de umidade, sólidos solúveis, cinzas, sólidos insolúveis, reação de Fiehe e reação de Lund, conforme as normas analíticas do Instituto Adolfo Lutz. Todas as amostras foram analisadas em triplicata. Para a umidade foram obtidos valores de 18,6% a 23%. Para os sólidos solúveis foram obtidos valores de 75º a 80 ºBrix. Cinzas apresentaram valores de 0,06% a 0,55%. Sólidos insolúveis variaram de 0,002 a 0,05%. Para a reação de Fiehe apenas uma amostra apresentou resultado negativo e para a reação de Lund os valores obtidos para o precipitado proteico variaram de 0,4 a 1,3 mL. Algumas amostras excederam o permitido para a umidade, reação de Fiehe e reação de Lund, embora esses dois últimos parâmetros não sejam considerados como essenciais na determinação da qualidade do mel. Os resultados apresentados neste estudo apontam que algumas amostras demonstram baixa qualidade sendo impróprias ao consumo humano
Modularity and evolutionary constraints in a baculovirus gene regulatory network
Abstract\ud
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Background\ud
The structure of regulatory networks remains an open question in our understanding of complex biological systems. Interactions during complete viral life cycles present unique opportunities to understand how host-parasite network take shape and behave. The Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) is a large double-stranded DNA virus, whose genome may encode for 152 open reading frames (ORFs). Here we present the analysis of the ordered cascade of the AgMNPV gene expression.\ud
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Results\ud
We observed an earlier onset of the expression than previously reported for other baculoviruses, especially for genes involved in DNA replication. Most ORFs were expressed at higher levels in a more permissive host cell line. Genes with more than one copy in the genome had distinct expression profiles, which could indicate the acquisition of new functionalities. The transcription gene regulatory network (GRN) for 149 ORFs had a modular topology comprising five communities of highly interconnected nodes that separated key genes that are functionally related on different communities, possibly maximizing redundancy and GRN robustness by compartmentalization of important functions. Core conserved functions showed expression synchronicity, distinct GRN features and significantly less genetic diversity, consistent with evolutionary constraints imposed in key elements of biological systems. This reduced genetic diversity also had a positive correlation with the importance of the gene in our estimated GRN, supporting a relationship between phylogenetic data of baculovirus genes and network features inferred from expression data. We also observed that gene arrangement in overlapping transcripts was conserved among related baculoviruses, suggesting a principle of genome organization.\ud
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Conclusions\ud
Albeit with a reduced number of nodes (149), the AgMNPV GRN had a topology and key characteristics similar to those observed in complex cellular organisms, which indicates that modularity may be a general feature of biological gene regulatory networks.JVCO, CTB and AI hold FAPESP scholarships (04/12456-0, 09/16740-8 and 12/04818-5), AFB and CCMF hold CAPES-MSc and PhD scholarships and PMAZ holds a CNPq-PQ scholarship. This work was supported financially by FAPESP (Fundação de Amparo a Pesquisa do Estado de São Paulo, process: 2007/55282-0)
Training Status as a Marker of the Relationship between Nitric Oxide, Oxidative Stress, and Blood Pressure in Older Adult Women
The purpose of this study was to evaluate the influence of functional fitness and oxidative capacity on the nitric oxide concentration associated with hemodynamic control in older adult women. The sample consisted of 134 women (65.73 ± 6.14 years old). All subjects underwent a physical examination to assess body mass index, waist-hip ratio, body fat measurement by dual energy X-ray absorptiometry, and blood pressure (BP). Training status (TS) was evaluated by indirect determination of maximal oxygen uptake by a treadmill test using Balke protocol modified for older adults. Functional fitness was also evaluated through a “Functional Fitness Battery Test” to determine the general fitness functional index (GFFI). All participants were separated according to the functional fitness (TS1, very weak and weak; TS2, regular; TS3, good and very good). Plasma blood samples were used to evaluate prooxidant and antioxidant activity and nitrite and nitrate concentrations. The general results of this study showed that good levels of TS were related to lower levels of lipoperoxidation and protein damage, higher levels of antioxidant, and higher concentration of nitrite and nitrate. This combination may be responsible for the lower levels of BP in subjects with better TS
Molecular evolution of zika virus during its emergence in the 20th century
Zika virus (ZIKV) is a mosquito-borne flavivirus first isolated in Uganda in 1947. Although entomological and virologic surveillance have reported ZIKV enzootic activity in diverse countries of Africa and Asia, few human cases were reported until 2007, when a Zika fever epidemic took place in Micronesia. In the context of West Africa, the WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever at Institut Pasteur of Dakar (http://www.pasteur.fr/recherche/banques/CRORA/) reports the periodic circulation of ZIKV since 1968. Despite several reports on ZIKV, the genetic relationships among viral strains from West Africa remain poorly understood. To evaluate the viral spread and its molecular epidemiology, we investigated 37 ZIKV isolates collected from 1968 to 2002 in six localities in Senegal and Côte d'Ivoire. In addition, we included strains from six other countries. Our results suggested that these two countries in West Africa experienced at least two independent introductions of ZIKV during the 20th century, and that apparently these viral lineages were not restricted by mosquito vector species. Moreover, we present evidence that ZIKV has possibly undergone recombination in nature and that a loss of the N154 glycosylation site in the envelope protein was a possible adaptive response to the Aedes dalzieli vector.Institute Pasteur of Dakar in SenegalFAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects #00/04205-6FAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects #08/17013-6FAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects#10/19341-4CAPES studentship, AI (project #12/04818-5)FAPESP scholarships and PMAZCNPq-PQNIH, R01-AI06914
Obesidade, ingestão de sódio e estilo de vida em hipertensos atendidos na ESF / Obesity, sodium intake and lifestyle in hypertensive patients treated at the FHS
Objetivou-se avaliar o estado nutricional, a ingestão diária de sódio e o estilo de vida em pacientes hipertensos. Aplicaram-se questionários semi-estruturados para avaliar ingestão de sódio e estilo de vida. Coletou-se o peso, a estatura, dobras cutâneas e circunferências para aferição antropométrica. Incluíram-se no estudo 42 indivíduos hipertensos atendidos em uma ESF, 54,76% são do sexo masculino. A média do IMC foi de 28,56 Kg/m², média do percentual de gordura corporal foi de 25,42. Quanto ao tabagismo, 11,90% (n=5) consomem mais de 20 cigarros por dia, constatou-se um alto consumo de bebida alcoólica, 64,29% (n=27) não seguem orientações dietéticas. O sedentarismo prevaleceu em 80,95% (n=34), O consumo médio de sódio foi de 4223,18 mg. Segundo IMC a maioria dos participantes encontram-se com sobrepeso e obesidade. Estilo de vida desfavorável com destaque para a inatividade física, etilismo e tabagismo, hábitos alimentares inadequados e uma alta ingestão de sódio
Phylogeographic Analysis of HIV-1 Subtype C Dissemination in Southern Brazil
The HIV-1 subtype C has spread efficiently in the southern states of Brazil (Rio Grande do Sul, Santa Catarina and Paraná). Phylogeographic studies indicate that the subtype C epidemic in southern Brazil was initiated by the introduction of a single founder virus population at some time point between 1960 and 1980, but little is known about the spatial dynamics of viral spread. A total of 135 Brazilian HIV-1 subtype C pol sequences collected from 1992 to 2009 at the three southern state capitals (Porto Alegre, Florianópolis and Curitiba) were analyzed. Maximum-likelihood and Bayesian methods were used to explore the degree of phylogenetic mixing of subtype C sequences from different cities and to reconstruct the geographical pattern of viral spread in this country region. Phylogeographic analyses supported the monophyletic origin of the HIV-1 subtype C clade circulating in southern Brazil and placed the root of that clade in Curitiba (Paraná state). This analysis further suggested that Florianópolis (Santa Catarina state) is an important staging post in the subtype C dissemination displaying high viral migration rates from and to the other cities, while viral flux between Curitiba and Porto Alegre (Rio Grande do Sul state) is very low. We found a positive correlation (r2 = 0.64) between routine travel and viral migration rates among localities. Despite the intense viral movement, phylogenetic intermixing of subtype C sequences from different Brazilian cities is lower than expected by chance. Notably, a high proportion (67%) of subtype C sequences from Porto Alegre branched within a single local monophyletic sub-cluster. These results suggest that the HIV-1 subtype C epidemic in southern Brazil has been shaped by both frequent viral migration among states and in situ dissemination of local clades
Does the disturbance hypothesis explain the biomass increase in basin-wide Amazon forest plot data?
Positive aboveground biomass trends have been reported from old-growth forests across the Amazon basin and hypothesized to reflect a large-scale response to exterior forcing. The result could, however, be an artefact due to a sampling bias induced by the nature of forest growth dynamics. Here, we characterize statistically the disturbance process in Amazon old-growth forests as recorded in 135 forest plots of the RAINFOR network up to 2006, and other independent research programmes, and explore the consequences of sampling artefacts using a data-based stochastic simulator. Over the observed range of annual aboveground biomass losses, standard statistical tests show that the distribution of biomass losses through mortality follow an exponential or near-identical Weibull probability distribution and not a power law as assumed by others. The simulator was parameterized using both an exponential disturbance probability distribution as well as a mixed exponential–power law distribution to account for potential large-scale blowdown events. In both cases, sampling biases turn out to be too small to explain the gains detected by the extended RAINFOR plot network. This result lends further support to the notion that currently observed biomass gains for intact forests across the Amazon are actually occurring over large scales at the current time, presumably as a response to climate change
Phylogenetic diversity of Amazonian tree communities
This is the peer reviewed version of the following article: Honorio Coronado, E. N., Dexter, K. G., Pennington, R. T., Chave, J., Lewis, S. L., Alexiades, M. N., Alvarez, E., Alves de Oliveira, A., Amaral, I. L., Araujo-Murakami, A., Arets, E. J. M. M., Aymard, G. A., Baraloto, C., Bonal, D., Brienen, R., Cerón, C., Cornejo Valverde, F., Di Fiore, A., Farfan-Rios, W., Feldpausch, T. R., Higuchi, N., Huamantupa-Chuquimaco, I., Laurance, S. G., Laurance, W. F., López-Gonzalez, G., Marimon, B. S., Marimon-Junior, B. H., Monteagudo Mendoza, A., Neill, D., Palacios Cuenca, W., Peñuela Mora, M. C., Pitman, N. C. A., Prieto, A., Quesada, C. A., Ramirez Angulo, H., Rudas, A., Ruschel, A. R., Salinas Revilla, N., Salomão, R. P., Segalin de Andrade, A., Silman, M. R., Spironello, W., ter Steege, H., Terborgh, J., Toledo, M., Valenzuela Gamarra, L., Vieira, I. C. G., Vilanova Torre, E., Vos, V., Phillips, O. L. (2015), Phylogenetic diversity of Amazonian tree communities. Diversity and Distributions, 21: 1295–1307. doi: 10.1111/ddi.12357, which has been published in final form at 10.1111/ddi.12357Aim: To examine variation in the phylogenetic diversity (PD) of tree communities across geographical and environmental gradients in Amazonia. Location: Two hundred and eighty-three c. 1 ha forest inventory plots from across Amazonia. Methods: We evaluated PD as the total phylogenetic branch length across species in each plot (PDss), the mean pairwise phylogenetic distance between species (MPD), the mean nearest taxon distance (MNTD) and their equivalents standardized for species richness (ses.PDss, ses.MPD, ses.MNTD). We compared PD of tree communities growing (1) on substrates of varying geological age; and (2) in environments with varying ecophysiological barriers to growth and survival. Results: PDss is strongly positively correlated with species richness (SR), whereas MNTD has a negative correlation. Communities on geologically young- and intermediate-aged substrates (western and central Amazonia respectively) have the highest SR, and therefore the highest PDss and the lowest MNTD. We find that the youngest and oldest substrates (the latter on the Brazilian and Guiana Shields) have the highest ses.PDss and ses.MNTD. MPD and ses.MPD are strongly correlated with how evenly taxa are distributed among the three principal angiosperm clades and are both highest in western Amazonia. Meanwhile, seasonally dry tropical forest (SDTF) and forests on white sands have low PD, as evaluated by any metric. Main conclusions: High ses.PDss and ses.MNTD reflect greater lineage diversity in communities. We suggest that high ses.PDss and ses.MNTD in western Amazonia results from its favourable, easy-to-colonize environment, whereas high values in the Brazilian and Guianan Shields may be due to accumulation of lineages over a longer period of time. White-sand forests and SDTF are dominated by close relatives from fewer lineages, perhaps reflecting ecophysiological barriers that are difficult to surmount evolutionarily. Because MPD and ses.MPD do not reflect lineage diversity per se, we suggest that PDss, ses.PDss and ses.MNTD may be the most useful diversity metrics for setting large-scale conservation priorities.FINCyT - PhD studentshipSchool of Geography of the University of LeedsRoyal Botanic Garden EdinburghNatural Environment Research Council (NERC)Gordon and Betty Moore FoundationEuropean Union's Seventh Framework ProgrammeERCCNPq/PELDNSF - Fellowshi
Large trees drive forest aboveground biomass variation in moist lowland forests accross the tropics
peer reviewedaudience: researcher, professional, studentAim Large trees (d.b.h. 70 cm) store large amounts of biomass. Several studies suggest that large trees may be vulnerable to changing climate, potentially leading to declining forest biomass storage. Here we determine the importance of large trees for tropical forest biomass storage and explore which intrinsic (species trait) and extrinsic (environment) variables are associated with the density of large trees and forest biomass at continental and pan-tropical scales.
Location Pan-tropical.
Methods Aboveground biomass (AGB) was calculated for 120 intact lowland moist forest locations. Linear regression was used to calculate variation in AGB explained by the density of large trees. Akaike information criterion weights (AICcwi) were used to calculate averaged correlation coefficients for all possible multiple regression models between AGB/density of large trees and environmental and species trait variables correcting for spatial autocorrelation.
Results Density of large trees explained c. 70% of the variation in pan-tropical AGB and was also responsible for significantly lower AGB in Neotropical [287.8 (mean) 105.0 (SD) Mg ha-1] versus Palaeotropical forests (Africa 418.3 91.8 Mg ha-1; Asia 393.3 109.3 Mg ha-1). Pan-tropical variation in density of large trees and AGB was associated with soil coarseness (negative), soil fertility (positive), community wood density (positive) and dominance of wind dispersed species (positive), temperature in the coldest month (negative), temperature in the warmest month (negative) and rainfall in the wettest month (positive), but results were not always consistent among continents.
Main conclusions Density of large trees and AGB were significantly associated with climatic variables, indicating that climate change will affect tropical forest biomass storage. Species trait composition will interact with these future biomass changes as they are also affected by a warmer climate. Given the importance of large trees for variation in AGB across the tropics, and their sensitivity to climate change, we emphasize the need for in-depth analyses of the community dynamics of large trees
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