6,060 research outputs found
Local vs. long-range infection in unidimensional epidemics
We study the effects of local and distance interactions in the unidimensional
contact process (CP). In the model, each site of a lattice is occupied by an
individual, which can be healthy or infected. As in the standard CP, each
infected individual spreads the disease to one of its first-neighbors with rate
, and with unitary rate, it becomes healthy. However, in our model, an
infected individual can transmit the disease to an individual at a distance
apart. This step mimics a vector-mediated transmission. We observe the
host-host interactions do not alter the critical exponents significantly in
comparison to a process with only L\'evy-type interactions. Our results
confirm, numerically, early field-theoretic predictions.Comment: 8 pages, 6 figures, to appear on Frontiers in Physic
Increasing genetic variability in black oats using gamma irradiation
The black oat (Avena strigosa Schreb) is commonly used for forage, soil cover, and green manure. Despite its importance,
little improvement has been made to this species, leading to high levels of genotypic disuniformity within commercial cultivars. The objective of this study was to evaluate the efficiency of different doses of gamma rays [ ^60 Co] applied to black oat seeds on the increase of genetic variability of agronomic traits. We applied doses of 0, 10, 50, 100, and 200 Gy to the genotype ALPHA 94087 through exposure to [ ^60 Co]. Two experiments were conducted in the winter of 2008. The first
aimed to test forage trait measurements such as plant height, dry matter yield, number of surviving tillers, and seedling stand. The second test assessed seed traits, such as yield and dormancy levels. Gamma irradiation seems not to increase seed yield in black oats, but it was effective in generating variability for the other traits. Tiller number and plant height are important selection traits to increase dry matter yield. Selection in advanced generations of mutant populations can increase
the probability of identifying superior genotypes
P18-10. Ability of HIV antigens-pulsed monocyte-derived dendritic cells to induce HIV-specific T cell response: potential use in therapeutic vaccine
Revisiting Natural Radiation in Itacaré and Guarapari Beaches
Human beings are constantly exposed to several types of natural radiation. This paper aims to study the total external dose from northwestern Brazilian beach sands. The samples were collected at Prainha in Itacaré, Bahia, and Praia de AreiaPreta in Guarapari, Espírito Santo. Gamma spectrometry is a very useful technique to estimate the effective dose due to naturally occurring radionuclides, such as 40K and daughters of 238U and 232Th. In order to confirm the high activity present in these two regions, the effective dose due to each natural radionuclide was determined. Moreover, the Energy-Dispersive X-Ray Spectroscopy (EDS) microanalysis was used to characterize the soil composition and the minerals responsible for the high activity. In addition, the sand samples were separated in to magnetic and non-magnetic fractions in order to identify the contribution from each portion of the activity. Finally, the radionuclides and their dispersion in those places are consistent with previous studies, indicating effective doses above the world average that is between 0.3 mSv/year and 1.0 mSv/year
Osteosarcopenia later in life: Prevalence and associated risk factors
Background and aims: The identification of risk factors for osteosarcopenia in older adults is important for planning preventative strategies in clinical practice. Therefore, our study aimed to investigate the prevalence and risk factors associated with osteosarcopenia in older adults using different diagnostic criteria. / Methods: The sample included 171 community-dwelling older adults with a mean age of 79.4 ± 5.9 years and mean body mass index of 25.67 ± 4.70 kg/m2. We analyzed sociodemographic, biomarkers, lifestyle, and health condition data from participants of the “Projeto Idosos - Goiânia” cohort study. The outcome osteosarcopenia was defined as the simultaneous occurrence of sarcopenia and osteopenia. Osteopenia was diagnosed by low lumbar spine bone mineral density (BMD) using dual-energy X-ray absorptiometry (DEXA). Sarcopenia was diagnosed using handgrip dynamometry and appendicular skeletal mass index assessed by DEXA following the criteria of the two European consensuses on sarcopenia (2010 and 2018). Two osteosarcopenia outcome variables were evaluated: OsteoSarc1 and OsteoSarc2 using the 2010 and 2018 European sarcopenia consensus criteria, respectively. Multivariate Poisson regression analysis was used to calculate the prevalence ratios (PRs). / Results: The prevalence of OsteoSarc1 and OsteoSarc2 were 12.8% and 7.2%, respectively, with no significant gender differences. OsteoSarc1 was associated with low potassium (PR: 3.39, 95% confidence interval [CI]: 1.10–10.43) and malnutrition (PR: 3.84, 95% CI: 1.78–8.30). OsteoSarc2 was associated with being ≥80 years (PR: 7.64, 95% CI: 1.57–37.07), >4 years of education (PR: 3.25, 95% CI: 1.03–10.22), alcohol consumption (PR: 2.41, 95% CI: 1.01–5.77), low potassium (PR: 2.22, 95% CI: 1.45–6.87), low serum vitamin D (PR: 4.47, 95% CI: 1.68–11.88), and malnutrition (PR: 5.00, 95% CI: 1.06–23.51). / Conclusions: OsteoSarc1 had a higher prevalence. The risk factors associated with the two outcomes were malnutrition and potassium level, as well as other risk factors, such as alcohol consumption and low vitamin D level. These findings may contribute to the prevention or treatment of this health condition in older adults
Efeito da densidade do solo na incidência de Fusarium spp.
O objetivo deste trabalho foi avaliar o efeito da densidade do solo resultante de dois sistemas de manejo e seis rotações de culturas na população de Fusarium spp
Identificação de genótipos de Manihot sp. com alelos de resistência ao vírus do Mosaico Africano.
O vírus do mosaico africano da mandioca (Cassava mosaic disease - CMD) é a virose mais importante da cultura, sendo encontrada na África, Índia, Malásia e Ásia. As epidemias são devastadoras podendo comprometer mais de 95% da produção (Jennings, 1994; Thresh et al., 1994). O vírus é transmitido pela mosca-branca Bemisia tabaci e disseminado pelo plantio de manivas infectadas.Fitosanidade. Resumo n. 185
Influência dos meios de cultura sólido e líquido no alongamento de brotos in vitro de abacaxi ornamental (Ananas lucidus Miller).
Influencia dos meios de cultura solido e liquido no alongamento de brotoss in vitro de abacaxi ornamental.bitstream/CNPAT-2010/5395/1/Pa-057.pd
Molecular Data Reveal Complex Hybridization and a Cryptic Species of Neotropical Wild Cat
SummaryHybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations [1–9]. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy’s cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south
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