2,629 research outputs found
A new species of Dasyhelea from Brazilian Amazonas and the description of the male of D. paulistana (Diptera: Ceratopogonidae)
A new species, Dasyhelea pseudopollinosa Díaz & Ronderos sp. nov., is described from Brazil, illustrated and photographed as pupae and male and female adults. The male of D. paulistana Forattini & Rabello, 1957 is described for the ¿ rst time, and the pupa and female adult are redescribed. Pupae of both species were collected from mats of À oating fern leaves (Salviniaceae and Azollaceae) in Brazil and Argentina, and exhibit a respiratory organ which is thick at the base and tapering to a sharp apex, and segment 9 with elongate, slender apicolateral process. Diffe rences between the two species are established, and they are also compared with Nearctic congeners that have the same kind of pupa: D. pollinosa Wirth, 1952, D. traverae Thomsen, 1935, and D. chani Wirth & Linley, 1990.Fil: Diaz, Maria Florentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Torreias, Sharlene R. S..Fil: Spinelli, Gustavo Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ronderos, Maria Marcela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentin
Diseño de un enlace WI-FI autónomo como una solución de conectividad para zonas rurales.
Este documento describe la experiencia de diseño, implementación y pruebas de campo de un enlace de largo alcance, alimentado con energía solar, utilizando radios Wi-Fi modificando parámetros de su MAC. El sistema es una alternativa para la conectividad de zonas rurales. Se utilizó el simulador RadioMobile durante el proceso de diseño. Se evaluó el desempeño del sistema entre dos estaciones separadas 10.22 Km alcanzándose una tasa promedio de transferencia en TCP de 13.8 Mbps. El sistema se diseñó para permitir una operación continua de 24 horas durante 3 días con bajos niveles de radiación solar
Diseño de un enlace WI-FI autónomo como una solución de conectividad para zonas rurales.
Este documento describe la experiencia de diseño, implementación y pruebas de campo de un enlace de largo alcance, alimentado con energía solar, utilizando radios Wi-Fi modificando parámetros de su MAC. El sistema es una alternativa para la conectividad de zonas rurales. Se utilizó el simulador RadioMobile durante el proceso de diseño. Se evaluó el desempeño del sistema entre dos estaciones separadas 10.22 Km alcanzándose una tasa promedio de transferencia en TCP de 13.8 Mbps. El sistema se diseñó para permitir una operación continua de 24 horas durante 3 días con bajos niveles de radiación solar
Identification and analysis of seven effector protein families with different adaptive and evolutionary histories in plant-associated members of the Xanthomonadaceae.
The Xanthomonadaceae family consists of species of non-pathogenic and pathogenic γ-proteobacteria that infect different hosts, including humans and plants. In this study, we performed a comparative analysis using 69 fully sequenced genomes belonging to this family, with a focus on identifying proteins enriched in phytopathogens that could explain the lifestyle and the ability to infect plants. Using a computational approach, we identified seven phytopathogen-enriched protein families putatively secreted by type II secretory system: PheA (CM-sec), LipA/LesA, VirK, and four families involved in N-glycan degradation, NixE, NixF, NixL, and FucA1. In silico and phylogenetic analyses of these protein families revealed they all have orthologs in other phytopathogenic or symbiotic bacteria, and are involved in the modulation and evasion of the immune system. As a proof of concept, we performed a biochemical characterization of LipA from Xac306 and verified that the mutant strain lost most of its lipase and esterase activities and displayed reduced virulence in citrus. Since this study includes closely related organisms with distinct lifestyles and highlights proteins directly related to adaptation inside plant tissues, novel approaches might use these proteins as biotechnological targets for disease control, and contribute to our understanding of the coevolution of plant-associated bacteria
High Human Herpesvirus 8 (HHV-8) Prevalence, Clinical Correlates and High Incidence among Recently HIV-1-Infected Subjects in Sao Paulo, Brazil
Background: Human herpesvirus 8 (HHV-8) is the etiological agent for Kaposi Sarcoma, which occurs especially in HIV-infected subjects. HHV-8 infection and its clinical correlates have not been well characterized in recently HIV-1-infected subjects, especially men who have sex with men (MSM).Methodology/Principal Findings: We assessed the HHV-8 seroprevalence, clinical correlates, and incidence after one year of follow-up in a cohort of 228 recently HIV-1-infected individuals, of whom 83.6% were MSM, using indirect immunofluorescence assay. the prevalence of HHV-8 infection at the time of cohort enrollment was 25.9% (59/228). in the univariate model, there were significant associations with male gender, black ethnicity, MSM practice, and previous hepatitis B virus and syphilis infections. in the multivariate model we could still demonstrate association with MSM, hepatitis B, and black ethnicity. No differences in mean CD4+ cell counts or HIV viral load according to HHV-8 status were found. in terms of incidence, there were 23/127 (18.1%) seroconversions in the cohort after 1 year.Conclusions: HHV-8 is highly prevalent among recently HIV-1-infected subjects. Correlations with other sexually transmitted infections suggest common transmission routes.Universidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilUniversidade Federal de São Paulo, Div Infect Dis, São Paulo, BrazilWeb of Scienc
The Brazilian Network for HIV-1 Genotyping External Quality Control Assurance Programme
The Brazilian network for genotyping is composed of 21 laboratories that perform and analyze genotyping tests for all HIV-infected patients within the public system, performing approximately 25,000 tests per year. We assessed the interlaboratory and intralaboratory reproducibility of genotyping systems by creating and implementing a local external quality control evaluation. Plasma samples from HIV-1-infected individuals (with low and intermediate viral loads) or RNA viral constructs with specific mutations were used. This evaluation included analyses of sensitivity and specificity of the tests based on qualitative and quantitative criteria, which scored laboratory performance on a 100-point system. Five evaluations were performed from 2003 to 2008, with 64% of laboratories scoring over 80 points in 2003, 81% doing so in 2005, 56% in 2006, 91% in 2007, and 90% in 2008 (Kruskal-Wallis, p = 0.003). Increased performance was aided by retraining laboratories that had specific deficiencies. The results emphasize the importance of investing in laboratory training and interpretation of DNA sequencing results, especially in developing countries where public (or scarce) resources are used to manage the AIDS epidemic
Spectrophotometric investigations of Blue Compact Dwarf Galaxies: Markarian 35
We present results from a detailed spectrophotometric analysis of the blue
compact dwarf galaxy Mrk 35 (Haro 3), based on deep optical (B,V,R,I) and
near-IR (J,H,K) imaging, Halpha narrow-band observations and long-slit
spectroscopy. The optical emission of the galaxy is dominated by a central
young starburst, with a bar-like shape, while an underlying component of stars,
with elliptical isophotes and red colors, extends more than 4 kpc from the
galaxy center. High resolution Halpha and color maps allow us to identify the
star-forming regions, to spatially discriminate them from the older stars, and
to recognize several dust patches. We derive colors and Halpha parameters for
all the identified star-forming knots. Observables derived for each knot are
corrected for the contribution of the underlying older stellar population, the
contribution by emission lines, and from interstellar extinction, and compared
with evolutionary synthesis models. We find that the contributions of these
three factors are by no means negligible and that they significantly vary
across the galaxy. Therefore, careful quantification and subtraction of
emission lines, galaxy host contribution, and interstellar reddening at every
galaxy position, are essential to derive the properties of the young stars in
BCDs. We find that we can reproduce the colors of all the knots with an
instantaneous burst of star formation and the Salpeter initial mass function
with an upper mass limit of 100 M_solar. In all cases the knots are just a few
Myr old. The underlying population of stars has colors consistent with being
several Gyr old.Comment: 21 pages, 13 figures. Accepted for publication in ApJ, tentatively
scheduled for the ApJ November 1, 2007 v669n1 issu
HIV-1 Proviral DNA Loads (as Determined by Quantitative PCR) in Patients Subjected to Structured Treatment Interruption after Antiretroviral Therapy Failure
The impact of Structured Treatment Interruption (STI) in peripheral blood mononuclear cell (PBMC) proviral reservoirs in 41 highly active antiretroviral therapy (HAART)-treated viremic individuals at baseline and 12 weeks after STI was determined using quantitative PCR (qPCR). Viral load increased 0.7 log(10) and CD4 decreased 97.5 cells/mm(3) after 12 weeks. A total of 28 of the 41 individuals showed an increased proviral load, 19 with a statistically significant increase above 10%. An increase in active viral replication is an important factor in the replenishment of the proviral reservoir even for short time periods.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [03/11781-1
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