RESUMO Objetivo: Apresentar a técnica de metanálise como uma estratégia aplicada à pesquisa bibliométrica para desvelar o estado da arte da produção científica internacional, suas interações com as áreas de conhecimento, a colaboração entre autores e instituições, na área da Administração, com base no período entre 1998 e 2017. Originalidade/valor: Na pesquisa exploratória inicialmente aplicada, observou-se uma lacuna no debate sobre o uso metanálise como um recurso de investigação do estado da arte na área da Administração. A metanálise utilizada como instrumento de pesquisa proporciona uma associação rigorosa de diversos estudos. Design/metodologia/abordagem: Trata-se de uma abordagem quali-quantitativa, de caráter exploratório-descritivo, delineada por pesquisa bibliográfica. Quanto ao mecanismo de investigação, foi usada a metanálise como uma investigação sistemática. O desenvolvimento da pesquisa foi realizado em duas etapas: macroanálise e microanálise. Resultados: Os resultados da pesquisa mostraram que o número de estudos bibliométricos publicados na segunda década estudada foi significantemente maior. As áreas de publicações, dentro do escopo da Administração também sofreram mudanças importantes quando se compararam os períodos analisados, evidenciando um crescimento de publicações entre 2008 e 2017 nas áreas de planejamento e gestão. Como aplicações práticas, podem-se, a partir deste estudo, utilizar as publicações e análises para melhor compreender como, quando, onde e por quem foram realizadas as bibliometrias, de forma que possam ser usadas para a realização de metanálises, ou seja, estudos bibliométricos mais densos e profundos, que possam evidenciar tendências em determinada área de estudo.

ABSTRACT Purpose: To present the meta-analysis technique as a strategy applied to bibliometric research, in order to unveil the state of the art of the international scientific production, its interactions as areas of knowledge, the collaboration among authors and institutions in the Business Administration area, based in the period from 1998 and 2017. Originality/value: In the initially applied exploratory research, it was observed a gap in the debate of using meta-analysis as a state of the art investigation resource in the Business Administration area. The meta-analysis used as a research instrument makes possible a strict association of several studies. Design/methodology/approach: It is a qual-quant research approach, of exploratory character, outlined through bibliographic research. As for the investigation mechanism, it was used meta-analysis as a systematic investigation. The development of the research was divided into two phases. The first, called macro-analysis, and the second, micro-analysis. Findings: Research results showed that the number of bibliometric studies published in the second decade of the studied period was significantly higher. The publication areas, within the scope of Administration, were also affected by important changes, comparing the analyzed periods, evidencing a growth in publications between 2008 and 2018 in the areas of planning and management. As practical applications, it is possible, from this study, to use the publications and analyses to better understand how, when and by whom the bibliometrics was made, that is, denser and deeper bibliometric studies, which can highlight trends in a certain study area.

Sugarcane bagasse fibers chemically modified on its surface were used to adsorb contaminants from biodiesel. Two biodiesel samples were used as adsorbates: crude and washed biodiesel. The contaminants were mainly glycerol and water, but also ions, and methanol. The biodiesel is usually washed, in order to remove most of the contaminants, but the procedure introduces large amounts of water, which are further difficult to remove, because the biodiesel acting as an acceptor of hydrogen bond. The adsorbent used in this work was proved to be very efficient to remove the contaminants and also to remove water from the washing the crude biodiesel. The contaminants adsorbed from biodiesel were identified by thermal analyses (DSC and DTA) of the fibers (adsorbent) and of the biodiesel (adsorbate) by comparing the results with the pure biodiesel. The proportion of free glycerol showed high adsorption efficiency for the crude biodiesel. A total amount of 1.34 g of fibers was estimated as being needed for its complete removal. The mass of bagasse fibers added (up to 1g) in a fixed volume of biodiesel was a relevant condition, as the saturation in fibers started at around 0.70 g cleaning up to about 98% removal of the impurities.

Neste trabalho, estudamos, à temperatura finita, a sistemática na formação dos momentos locais de uma impureza de Ta diluída em compostos intermetálicos de fases de Laves XFe2 (X = Y, Gd, Yb). Utilizamos um hamiltoniano de Hubbard, extendido à duas sub-redes acopladas, para descrever as matrizes de fases de Laves. A interação eletrônica d-d é tratada via método da integral funcional, na aproximação quase estática. Efeitos da pressão dependentes da temperatura estão incluídos, considerando a interação elétron-fônon induzida que renormaliza a hibridização do elétron puro. Os campos hiperfinos magnéticos calculados, relacionados aos momentos magnéticos locais, estão em bom acordo com os dados experimentais avaliados.

In this work, we study the systematics, at finite temperature, of the formation of local magnetic moments at a Ta impurity diluted in intermetallic Laves phases compounds XFe2 (X = Y, Gd, Yb). We use an extended two-coupled sublattice Hubbard Hamiltonian, to describe the Laves phases host. The d-d electronic interaction is treated via a functional integral approach in the quasi-static saddle point approximation. Temperature dependent pressure effects are included considering induced electron-phonon interaction which renormalizes the pure electron hybridization. The calculated magnetic hyperfine fields related to the obtained local magnetic moments, are in a quite good agreement with available experimental data.

Hoje, já existem vários estudos sobre a eficiência operacional de colheita mecanizada do café, porém pouco se sabe sobre a influência da vibração das hastes e a velocidade de deslocamento da colhedora nesse processo. Assim, este trabalho teve por objetivo avaliar a influência da vibração das hastes e da velocidade de deslocamento da colhedora no processo de colheita mecanizada do café. O trabalho foi desenvolvido na Fazenda Capetinga, sul de Minas Gerais. Para os ensaios, utilizou-se do delineamento inteiramente casualizado, com quatro repetições, em parcelas aleatórias, contendo, em média, 40 plantas em fileira. Os ensaios foram realizados com duas passadas da colhedora, definidos em função do índice de frutos verdes na planta. A primeira passada foi realizada com média de 30% de verde, e a segunda, com média de 10% de verde. Concluiu-se que, na primeira passada, o volume de café colhido, a desfolha e a eficiência de derriça foram 29,25%, 31,12% e 31,85%, respectivamente, superiores na maior vibração. Na segunda passada, na maior velocidade operacional, o volume de café caído no chão variou 61,2% em relação à menor velocidade, e a redução no volume colhido e na eficiência de colheita variou de14,28% da menor para a maior velocidade operacional.

Nowadays, there are many studies about the efficiency of the mechanized coffee harvest but not much is known about the influence of the sticks vibration and the speed of the harvester machine on the mechanized coffee harvest process. The goal of this paper was to evaluate this influence. The study was conducted at the Capetinga Farm, south of the state of Minas Gerais. For the experiments, it was utilized the randomized design with four repetitions in aleatory portions having, on average, 40 plants in each line. The experiments were done with two runs of the harvester considering the green coffee berries rate. The first run was done having 30% of green coffee berries and, on the second one, about 10% of green coffee berries. It was concluded that, on the first run, the volume of coffee berries harvested, the leaf loss and the seed dropping efficiencies were 29.25%, 31.12% and 31.85%, respectively, having better results when operating with the highest vibration. On the second run, with the highest operational speed, the volume of coffee berry that fell on the ground varied 61.2% in relation to the lowest speed and the reduction on the harvested volume and in the harvest efficiency varied 14.28% from the lowest to the highest operational speed.

OBJECTIVE: To assess the clinical, electrocardiographic, and electrophysiologic characteristics of patients (pt) with intra-His bundle block undergoing an electrophysiologic study (EPS). METHODS: We analyzed the characteristics of 16 pt with second-degree atrioventricular block and symptoms of syncope or dyspnea, or both, undergoing conventional EPS. RESULTS: Intra-His bundle block was documented in 16 pt during an EPS. In 15 (94%) pt, the atrioventricular block was recorded in sinus rhythm; 4 (25%) pt had intra-His Wenckebach phenomenon, which correlated with Mobitz I (MI) atrioventricular block on the electrocardiogram. Seven (44%) pt had 2:1 atrioventricular block, 2 of whom were asymptomatic (12.5%). One (6%) pt had intra- and infra-His bundle block. Clinically, 11 (68%) pt had syncope or presyncope, 3 (18%) had dyspnea on exertion, and 2 (12.5%) were asymptomatic. Eight (50%) pt had bundle-branch block as follows: 4 (25%) pt had left bundle-branch block, and 4 (25%) had right bundle-branch block. Left anterosuperior divisional block was observed in 3 pt (19%), 2 of whom with associated right bundle-branch block. CONCLUSION: Intra-His bundle block was observed in 11% of the pt with second-degree atrioventricular block, syncope or presyncope, or both, it being the most frequent clinical presentation. Intra-His bundle block was more common in the elderly (> 60 years) and among females. The most frequent electrocardiographic presentations were second-degree Mobitz I or type 2:1 atrioventricular block.