1,582 research outputs found
Avaliação da atividade sexual pré-zigótica de populações de Anastrepha fraterculus (Wiedmann, 1830) (Diptera: Tephritidae).
Neste trabalho foi avaliada a competitividade sexual pré-zigótica das populações de A. fraterculus: 1) selvagem; 2) laboratório (78° geração) e 3) laboratório esterilizadas
Competitividade sexual pré-zigótica em Mosca-das-frutas Anastrepha Fraterculus (Wiedmann, 1830) (Diptera: Tephritidae).
A mosca-das-frutas Anastrepha fraterculus é a principal praga da maçã e a técnica do inseto estéril seria uma alternativa para seu controle. O presente trabalho avaliou a competitividade sexual pré-zigótica entre três populações de A. fraterculus: selvagens, de laboratório e laboratório esterilizadas. O estudo foi conduzido em gaiolas teladas na Estação Experimental de Fruticultura de Clima Temperado (EEFCT), Vacaria, RS. A população selvagem foi obtida dos frutos de Feijoa sellowiana e as de laboratório obtidas da criação experimental do Laboratório de Entomologia da EEFTC, criadas artificialmente. O processo de esterilização foi realizado pelo Centro de Energia Nuclear na Agricultura, Piracicaba, SP, em pupas 24 horas antes da emergência, a uma taxa de 135,65 Gy/h. Logo após a emergência os adultos foram separados por sexo e alimentados de acordo com o sistema de criação. No dia anterior ao teste foram identificados com tinta. Os ensaios foram conduzidos às 8:00 da manhã liberando-se 30 machos de cada população e 30 minutos depois as respectivas fêmeas. Para população de laboratório foram usados adultos de 8 a 10 dias de idade e para selvagem de 15 a 18 dias. Para cada combinação foram realizadas oito repetições. Foram observados e capturados os casais formados registrando a cor e a duração das cópulas. Todas as observações foram realizadas do interior da gaiola durante 3 horas. Os casais foram separados em gaiolas de acordo com sua combinação para avaliação da viabilidade dos ovos. Os resultados foram analisados de acordo com o Índice de Isolamento Sexual (ISI) e os relativos à viabilidade de ovos foram comparados ao padrão da espécie. Os resultados indicaram que há compatibilidade sexual entre as populações, mas que o processo de radioesterilização afetou a competitividade sexual. Os ovos obtidos de cópulas envolvendo a população esterilizada geraram ovos inviáveis e as fêmeas estéreis não produziram ovos
Expressive Aphasia and Carotid Dissection
Ultrasound images of a patient presenting to the emergency department with expressive aphasia who was found to have carotid dissection. The first image is a standard two dimensional image that depicts the internal carotid with a visible flap within the lumen. The second image is a color Doppler image showing turbulent flow within the true lumen and visible flow within the false lumen. The case and the patient’s outcome are summarized along with some teaching points about carotid dissection. Also, there is some background and research on using ultrasound to help identify dissection
Growth of different fruit tree species in silvopastoral systems during the establishment phase.
EN-US: The benefits of integrating agricultural components into silvopastoral systems are widely known, but the limited knowledge about ecological processes in the establishment phase impedes the use of this technology. The objective of this study was to evaluate interactions between fruit tree species and the sward layer under canopies of trees in the establishment phase of silvopastoral systems in Mato Grosso, Brazil. The experiment was implemented in October 2013, with an evaluation period from January to July 2015. The systems were composed of eight fruit trees intercropped with Tifton 85 grass. A completely randomized block design was adopted, with two replications per area per treatment. We evaluated the agronomic performance of the fruit trees, the categories of the light environment, and the plant accumulation under the canopies. The acerola fruit trees of the variety Roxinha had higher Leaf area index (LAI) and Light interception (LI) values, showing a denser canopy with small porosity and the lowest light quality available to the plants beneath the canopy (lower red/far-red ratio), thereby decreasing plant accumulation under trees. The guava fruit trees showed higher growth rates than the other fruit trees, but lower LAI and LI values and a higher red/far-red ratio, allowing higher plant growth under the canopy. Cajá trees showed a similar behavior; however, this species is deciduous, which limits its potential use in integrated systems. Banana and coconut trees were highly dependent on irrigation during the dry season. The remaining species showed an adequate growth and potential to control plant species growth under their canopies. | PT-BR: Os benefícios de integrar os componentes agrícolas já são bastante conhecidos, porém o conhecimento sobre os processos ecológicos da competição das plantas ainda é uma barreira para essa tecnologia. O objetivo deste estudo foi avaliar a interação entre espécies fruteiras e a vegetação sob suas copas na fase de estabelecimento de sistemas silvipastoris no Mato Grosso, Brasil. O experimento foi implantado em 2013 e avaliado em 2015. Estes sistemas foram compostos por oito espécies de fruteiras consorciadas com Tifton-85. O delineamento experimental foi em blocos completos casualizados com duas repetições de área por tratamento. Foi avaliado o desempenho agronômico das espécies fruteiras, caracterização do ambiente luminoso e o acumulo de material vegetal sob as copas. A aceroleira Roxinha apresentou os maiores valores de índice de área foliar (IAF) e interceptação luminosa (IL) devido a um dossel mais denso com baixa porosidade e a menor qualidade de luz disponível sob as copas das árvores (menor relação vermelho/vermelho distante – V/Vd), condicionando a uma redução no acúmulo de material vegetal sob as copas. As goiabeiras cresceram mais do que as outras espécies, contudo apresentaram os menores valores de IAF e IL e alta relação V/Vd, permitindo a presença de mais plantas sob sua copa. Cajazeira demonstrou resposta similar, contudo esta espécie é decídua, podendo apresentar um potencial mais limitado em sistemas integrados. Bananeira e coqueiro mostraram uma grande dependência de irrigação durante a estação seca. As demais espécies apresentaram um crescimento adequado e potencial para controlar o crescimento das plantas sob suas copas
Ghrelin regulates proliferation and differentiation of osteoblastic cells
Abstract
It has previously been reported that growth hormone secretagogues (GHS) may have a role in the regulation of bone metabolism in animals and humans. In this study we evaluated the effect of ghrelin, the endogenous ligand of GHS receptors, on the proliferation rate and on osteoblast activity in primary cultures of rat calvaria osteoblasts. In the same experiments, we compared the effects of ghrelin with those of hexarelin (HEXA) and EP-40737, two synthetic GHS with different characteristics. Both ghrelin and HEXA (10(-11)-10(-8) M) significantly stimulated osteoblast proliferation at low concentrations (10(-10) M). Surprisingly, EP-40737 demonstrated an antiproliferative effect at 10(-9)-10(-8) M, whereas lower concentrations had no effect on cell proliferation. Ghrelin and HEXA significantly increased alkaline phosphatase (ALP) and osteocalcin (OC) production. At variance with these peptides, EP-40737 did not significantly stimulate ALP and OC. The mRNA for GHS-R1a receptors and the corresponding protein were detected in calvarial osteoblasts by RT-PCR and Western blot respectively, indicating that ghrelin and GHS may bind and activate this specific receptor. We conclude that endogenous ghrelin and synthetic GHS modulate proliferation and differentiation of rat osteoblasts, probably by acting on their specific receptor
Erectile dysfunction and angiographic extent of coronary artery disease in type II diabetic patients
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Diversity and genetic structure of the native Brazil nut tree (Bertholletia excelsa Bonpl.) population.
The present study was carried out in a native Brazil nut tree population (Bertholletia excelsa Bonpl., Lecythidaceae) to assess its genetic diversity and structure. Ten microsatellite markers were used to genotype 198 adult trees (B. excelsa). The population presented high genetic diversity and inbreeding absence rates. The empirical Bayesian method showed three distinct groups in the structure of this population. Molecular analysis of variance showed 98% variability within groups, and 2% between groups. The genetic divergence (FST) indicated little difference between groups; thus, suggesting efficient gene flow between the analyzed B. excelsa adult trees
Spectral signatures of many-body localization with interacting photons
Statistical mechanics is founded on the assumption that a system can reach
thermal equilibrium, regardless of the starting state. Interactions between
particles facilitate thermalization, but, can interacting systems always
equilibrate regardless of parameter values\,? The energy spectrum of a system
can answer this question and reveal the nature of the underlying phases.
However, most experimental techniques only indirectly probe the many-body
energy spectrum. Using a chain of nine superconducting qubits, we implement a
novel technique for directly resolving the energy levels of interacting
photons. We benchmark this method by capturing the intricate energy spectrum
predicted for 2D electrons in a magnetic field, the Hofstadter butterfly. By
increasing disorder, the spatial extent of energy eigenstates at the edge of
the energy band shrink, suggesting the formation of a mobility edge. At strong
disorder, the energy levels cease to repel one another and their statistics
approaches a Poisson distribution - the hallmark of transition from the
thermalized to the many-body localized phase. Our work introduces a new
many-body spectroscopy technique to study quantum phases of matter
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A consensus on the diagnosis and treatment of acromegaly complications
In March 2011, the Acromegaly Consensus Group met to revise and update the guidelines on the diagnosis and treatment of acromegaly complications. The meeting was sponsored by the Pituitary Society and the European Neuroendocrinology Association and included experts skilled in the management of acromegaly. Complications considered included cardiovascular, endocrine and metabolic, sleep apnea, bone diseases, and mortality. Outcomes in selected, related clinical conditions were also considered, and included pregnancy, familial acromegaly and invasive macroadenomas. The need for a new disease staging model was considered, and design of such a tool was proposed
Meta-Analysis on the Effects of Octreotide on Tumor Mass in Acromegaly
<div><h3>Background</h3><p>The long-acting somatostatin analogue octreotide is used either as an adjuvant or primary therapy to lower growth hormone (GH) levels in patients with acromegaly and may also induce pituitary tumor shrinkage.</p> <h3>Objective</h3><p>We performed a meta-analysis to accurately assess the effect of octreotide on pituitary tumor shrinkage.</p> <h3>Data Sources</h3><p>A computerized Medline and Embase search was undertaken to identify potentially eligible studies.</p> <h3>Study Eligibility Criteria</h3><p>Eligibility criteria included treatment with octreotide, availability of numerical metrics on tumor shrinkage and clear definition of a clinically relevant reduction in tumor size. Primary endpoints included the proportion of patients with tumor shrinkage and mean percentage reduction in tumor volume.</p> <h3>Data Extraction and Analysis</h3><p>The electronic search identified 2202 articles. Of these, 41 studies fulfilling the eligibility criteria were selected for data extraction and analysis. In total, 1685 patients were included, ranging from 6 to 189 patients per trial. For the analysis of the effect of octreotide on pituitary tumor shrinkage a random effect model was used to account for differences in both effect size and sampling error.</p> <h3>Results</h3><p>Octreotide was shown to induce tumor shrinkage in 53.0% [95% CI: 45.0%–61.0%] of treated patients. In patients treated with the LAR formulation of octreotide, this increased to 66.0%, [95% CI: 57.0%–74.0%). In the nine studies in which tumor shrinkage was quantified, the overall weighted mean percentage reduction in tumor size was 37.4% [95% CI: 22.4%–52.4%], rising to 50.6% [95% CI: 42.7%–58.4%] with octreotide LAR.</p> <h3>Limitations</h3><p>Most trials examined were open-label and had no control group.</p> <h3>Conclusions</h3><p>Octreotide LAR induces clinically relevant tumor shrinkage in more than half of patients with acromegaly.</p> </div
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