Electronic Structure Calculations in a 2D SixGe1-x Alloy Under an Applied Electric Field.

The recent advances and promises in nanoscience and nanotechnology have been focused on hexagonal materials, mainly on carbon-based nanostructures. Recently, new candidates have been raised, where the greatest efforts are devoted to a new hexagonal and buckled material made of silicon, named Silicene. This new material presents an energy gap due to spin-orbit interaction of approximately 1.5 meV, where the measurement of quantum spin Hall effect(QSHE) can be made experimentally. Some investigations also show that the QSHE in 2D low-buckled hexagonal structures of\ud germanium is present. Since the similarities, and at the same time the differences,\ud between Si and Ge, over the years, have motivated a lot of investigations in these\ud materials. In this work we performed systematic investigations on the electronic\ud structure and band topology in both ordered and disordered SixGe1-x alloys monolayer\ud with 2D honeycomb geometry by first-principles calculations. We show that\ud an applied electric field can tune the gap size for both alloys. However, as a function\ud of electric field, the disordered alloy presents a W-shaped behavior, similarly to the\ud pure Si or Ge, whereas for the ordered alloy a V-shaped behavior is observed.CAPESCNPqFAPES

Pesquisa de ovos de helmintos e de cistos de protozoários em dinheiro

Due to the high prevalence of intestinal parasitic diseases in Brazil and to the fact that inanimate objects may play an important role in their transmission, it was decided to carry out an investigation into the existence of helminthic eggs and protozoan cysts in money currently handled by the community. A thousand and three banknotes and 1,011 coins of different origins were analysed, yielding the following results. Entamoeba histolytica cysts were found twice, and fertile and infertile Ascaris lumbricoides eggs and one intact Taenia sp. egg, besides other nonpathogenic elements, were also found. The importance of the handling of money in the epidemiology of common intestinal parasitic diseases is emphasized and it is suggested that further similar studies should be carried out; possible means of prevention are also indicated.Em virtude da elevada prevalência de parasitoses intestinais no Brasil e da possível participação de objetos na transmissão dessas afecções, foi desenvolvida pesquisa envolvendo dinheiro difundido na coletividade. Foram analisadas, quanto à presença de ovos de helmintos e de cistos de protozoários, 1.003 cédulas e 1.011 moedas, de valores e procedências diversos. Do estudo resultou o encontro de cistos de Entamoeba histolytica em duas eventualidades, de ovos de Ascaris lumbricoides larvado e infértil, de ovo de Taenia sp. morfologicamente íntegro e de outros elementos não patogênicos. Ficou salientada a importância do dinheiro circulante na epidemiologia das enteroparasitoses, tendo havido sugestão de novos trabalhos de natureza congênere, inclusive delineando diretrizes de ordem profilática

VARIABILIDADE ESPACIAL DE ALGUNS ATRIBUTOS QUÍMICOS EM ÁREAS CULTIVADAS COM SOJA E ARROZ NO ESTADO DE RORAIMA - CONTRIBUIÇÕES DA AGRICULTURA DE PRECISÃO

The state of Roraima has an area of ??225 116 km2, representing 2.64% of the national territory and 5.81% in the northern region. detailed knowledge of the spatial variability of soil fertility attributes can improve the localized applications of lime and fertilizers. The objective of this study was to evaluate the variability of some attributes (ph, ca +2 and p) chemical soil under cultivation of soybean and rice in the state of Roraima, with the help of precision agriculture. Soil sampling was conducted in 3265 ha, with sampling grid of 5 ha, totaling 653 sampling points (composite samples). Each composite sample was georeferenced and formed from 10 single samples collected in a circle around each sampling grid, thus resulting in a total of 6530 samples collected simple. For soils assessed with precision agriculture of the two municipalities, the attributes showed satisfactory levels of variation (available p) disabled (ca available), and very low (pH).   Keywords: georeferencing, grains, soil fertility.  O Estado de Roraima possui uma superfície de 225.116 km2, representando 2,64% do território nacional e 5,81% da Região Norte. O conhecimento detalhado da variabilidade espacial dos atributos da fertilidade do solo pode aperfeiçoar as aplicações localizadas de corretivos e fertilizantes. Objetivou-se neste trabalho, avaliar a variabilidade de alguns atributos (pH, Ca+2 e P) químicos de solos sob cultivo de soja e arroz no estado de Roraima, com auxílio da Agricultura de Precisão. A amostragem do solo foi realizada em 3265 ha, com grade amostral de 5 ha, perfazendo o total de 653 pontos amostrais (amostras compostas). Cada amostra composta foi georreferenciada e formada a partir de 10 amostras simples coletadas em um círculo ao redor de cada grade de amostragem, resultando assim num total de 6530 amostras simples coletadas. Para os solos avaliados com agricultura de precisão dos dois municípios, os atributos mostraram variação de níveis satisfatórios (P disponível) a deficientes (Ca disponível), e muito baixo (pH). PALAVRAS-CHAVE: fertilidade do solo, georreferenciamento, grãos

Evaluation of the activity of albendazole in the therapy of experimentally-infected rats

In order to settle the precise spectrum of activity of albendazole, its efficacy was tested in the treatment of Strongyloides venezuelensis in experimentally-infected rats. The results were compared to those obtained with two other benzimidaloze derivatives, cambendazole and mebendazole. The three compounds were shown to be effective in eradicating intestinal adult worms completely, when single doses of 625, 12.5, 25 of 50 mg/kg were used. However when smaller doses were employed (5 mg/kg) worm burdens were reduced in 87%, 98% and 80% by albendazole, cambendazole and mebendazole respectively.Com a finalidade de demarcar mais precisamente o espectro de ação do albendazol, foi estudada a atividade terapêutica desse anti-helmíntico em ratos experimentalmente infectados com Strongyloides venezuelensis, tendo sido usada, como termo de comparação, a ação do cambendazol e do mebendazol, dois outros benzimidazólicos. Os três compostos mostraram-se eficientes quando utilizadas doses únicas de 6,75, 12,5, 25 e 50 mg/kg, pois motivaram desaparecimento total das formas adultas no intestino. Com a posologia de 5 mg/kg sucederam porcentagens médias de reduções dos números de vermes de 87%, 98% e 80%, respectivamente, como decorrência do emprego do albendazol, do cambendazol e do mebendazol, traduzindo superioridade da segunda droga citada

Avaliação da atividade terapêutica do albendazol em ratos experimentalmente infectados com Strongyloides venezuelensis

Com a finalidade de demarcar mais precisamente o espectro de ação do albendazol, foi estudada a atividade terapêutica desse anti-helmíntico em ratos experimentalmente infectados com Strongyloides venezuelensis, tendo sido usada, como termo de comparação, a ação do cambendazol e do mebendazol, dois outros benzimidazólicos. Os três compostos mostraram-se eficientes quando utilizadas doses únicas de 6,75, 12,5, 25 e 50 mg/kg, pois motivaram desaparecimento total das formas adultas no intestino. Com a posologia de 5 mg/kg sucederam porcentagens médias de reduções dos números de vermes de 87%, 98% e 80%, respectivamente, como decorrência do emprego do albendazol, do cambendazol e do mebendazol, traduzindo superioridade da segunda droga citada.In order to settle the precise spectrum of activity of albendazole, its efficacy was tested in the treatment of Strongyloides venezuelensis in experimentally-infected rats. The results were compared to those obtained with two other benzimidaloze derivatives, cambendazole and mebendazole. The three compounds were shown to be effective in eradicating intestinal adult worms completely, when single doses of 625, 12.5, 25 of 50 mg/kg were used. However when smaller doses were employed (5 mg/kg) worm burdens were reduced in 87%, 98% and 80% by albendazole, cambendazole and mebendazole respectively