Federal University of Mato Grosso do Sul

About: Federal University of Mato Grosso do Sul is a education organization based out in Campo Grande, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 6903 authors who have published 9030 publications receiving 78977 citations. The organization is also known as: UFMS & Federal University of Mato Grosso do Sul.

Utilizando estudo de caso(s) como estratégia de pesquisa qualitativa: boas práticas e sugestões

Abstract: A contribuicao deste artigo e apresentar uma reflexao sobre a estrategia de estudo de casos, a qual vem sendo adotada em larga escala por pesquisadores das areas de Administracao e correlatas. Baseando-se em uma expressiva revisao da literatura e na experiencia de pesquisa dos autores, registra-se um roteiro de etapas para os interessados na estrategia de estudo de caso. Adicionalmente, em cada uma dessas etapas sao assinalados desafios e oportunidades para a realizacao de estudo de caso(s) que contribua(m) significativamente ao estado da arte em que se insere(m). Espera-se que este artigo possa contribuir com pesquisadores iniciantes ou experientes, a medida que se lancam no desafio de planejar e aplicar estudo de caso(s) em suas pesquisas.

Evidence that lipopolisaccharide may contribute to the cytokine storm and cellular activation in patients with visceral leishmaniasis

Abstract: Background Visceral leishmaniasis (VL) is characterized by parasite-specific immunosuppression besides an intense pro-inflammatory response. Lipopolisaccharide (LPS) has been implicated in the immune activation of T-cell deficient diseases such as HIV/AIDS and idiopathic lymphocytopenia. The source of LPS is gram-negative bacteria that enter the circulation because of immunological mucosal barrier breakdown. As gut parasitization also occurs in VL, it was hypothesized that LPS may be elevated in leishmaniasis, contributing to cell activation.

Competition and resource breadth shape niche variation and overlap in multiple trophic dimensions.

Abstract: Competition plays a central role in the maintenance of biodiversity. A backbone of classic niche theory is that local coexistence of competitors is favoured by the contraction or divergence of species' niches. However, this effect should depend on the diversity of resources available in the local environment, particularly when resources vary in multiple ecological dimensions. Here, we investigated how available resource breadth (i.e. prey diversity) and competition together shape multidimensional niche variation (between and within individuals) and interspecific niche overlap in 42 populations of congeneric tropical frog species. We modelled realized niches in two key trophic dimensions (prey size and carbon stable isotopes) and sampled available food resources to quantify two-dimensional resource breadth. We found a 14-fold variation in multidimensional population niche width across populations, most of which was accounted for by within-individual diet variation. This striking variation was predicted by an interaction whereby individual niche breadth increased with resource breadth and decreased with the number of congeneric competitors. These ecological gradients also interact to influence the degree of niche overlap between species, which surprisingly decreased with population total niche width, providing novel insights on how similar species can coexist in local communities. Together, our results emphasize that patterns of exploitation of resources in multiple dimensions are driven by both competitive interactions and extrinsic factors such as local resource breadth.

Biomonitoring of methomyl pesticide by laccase inhibition on sensor containing platinum nanoparticles in ionic liquid phase supported in montmorillonite

Abstract: This study focuses on the development and evaluation of a new biosensor for the determination of the pesticide methomyl, based on enzyme inhibition. Laccase (LAC) obtained from a genetically modified fungus (Aspergillus oryzae) was successfully immobilized in a new supported ionic liquid phase (SILP) based on platinum nanoparticles and the 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid (Pt–BMI·BF4) supported in montmorillonite, and subsequently applied in the construction of the biosensor. The process of inhibition by methomyl carbamate was performed using dopamine as a phenolic substrate to obtain the base signal. All measurements for the optimization and application of the biosensor were performed by square-wave voltammetry, and the best experimental conditions were obtained in acetate buffer solution (0.1 mol L−1, pH 5.5), with 0.5 units of enzyme and voltammetric parameters: 60 Hz of frequency, 100 mV of pulse amplitude and 8 mV of scan increment. The determination of methomyl in carrot and tomato samples using the proposed biosensor showed results consistent with those obtained by HPLC, verifying that the method developed can be used for the quantification of this pesticide.