2,907 research outputs found
Hormonal status, creatine kinase and soccer: a need for research
Soccer is a physically demanding sport in which muscular damage and trauma are
frequent occurrences. These occurrences are especially true for those athletes
involved in top-division clubs at national or international levels. Many factors
may come into play when determining the degree of muscular damage that may occur
during a soccer match, such as intensity of physical participation, environmental
conditions, skill level, prior level of rest, and aggressiveness of the teams involved in
the match
Una aproximación histórica a las representaciones contables en Colombia. (A historical approach to accounting representations in Colombia).
En este trabajo se realiza un abordaje de las representaciones contables para analizar cómo han evolucionado a través del tiempo, desde el marco interpretativo de la nueva historia. Representaciones tales como información, certificación y control, entre otras, desde el plano praxiológico han estado presentes, con dinámicas propias, en la historia de la profesión contable en Colombia, tomando como fuente las normas que se expiden desde un enfoque público, demarcando una identidad histórica que permite comprender la complejidad de los elementos que confluyen en la práctica y el saber contables contemporáneos. This paper is an approach to analyze the evolution of accounting representations in the course of time from the new history interpretative point of view. Representations such as information, certifying and control, among others, have been present in the history of the accounting profession in Colombia. They have developed following their own dynamics within the framework provided by the norms dictated by the public authorities. Their evolution demarcates a historical identity that allows the understanding of the complex ensemble of elements that shape the contemporary accounting praxis and knowledge.Historia de la contabilidad,información, certificación y control, Colombia. Accounting history, information, certifying and control, Colombia.
O responder controlado temporalmente: desdobramentos da pesquisa com a tarefa de bissecção
info:eu-repo/semantics/publishedVersio
Context effects in temporal differentiation: some data and a model
We examined whether temporal context influences how animals produce a time interval. Six pigeons pecked one key to start an interval and then another key to end the interval. Reinforcement followed whenever the interval duration fell within a range of values signaled by the keylight colors. During Phase 1, keylight colors S1 and L1, intermixed across trials, signaled the ranges (0.5-1.5 s) and (1.5- 4.5 s), respectively. During Phase 2, colors S2 and L2 signaled the ranges (1.5-4.5 s) and (4.5-13.5 s), respectively. We asked whether the intervals produced in the presence of L1 and S2, stimuli signalling the same range, varied with their temporal context, short in Phase 1, long in Phase 2. The results showed that a) the intervals produced in the presence of the different keylight colors accorded with the main properties of temporal differentiation, including Weber’s law, b) the L1 intervals had slightly higher means than the S2 intervals, a weak contrast effect, c) the L1 intervals also had higher variability than the S2 intervals. An extension of the learning-to-time model to temporal differentiation tasks reproduced some of the major features of the data but left unanswered how context might change the model parameters.MPC, AM, and MV benefited from grants from the Portuguese Foundation for Science and Technology (FCT SFRH/BD/73875/2010, PTDC/MHC-PCN/3540/2012, and IF/01624/2013/CP1158/CT0012, respectively). This study was conducted at the Psychology Research Centre, University of Minho, and partially supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Education and Science through national funds and when applicable co-financed by FEDER under the PT2020 Partnership Agreement (UID/PSI/01662/2013). The authors thank Catarina Soares, Margarida Monteiro, Francisca Cunha, Janete Silva, Lénia Amaral, Pilar Niño and Sofia Ribeiro for help collecting data.info:eu-repo/semantics/publishedVersio
Effects of the non-indigenous bivalve Ruditapes philippinarum on meiofaunal communities of the Tagus Estuary
A meiofauna é, atualmente, considerada como um grupo de organismos com elevado
potencial para a monitorização de eventuais efeitos ecológicos resultantes de
perturbações naturais e/ou antropogénicas nos ecossistemas aquáticos. A presença do
bivalve não-indígena R. philippinarum no estuário do Tejo apresentou uma
oportunidade para avaliar o uso das comunidades da meiofauna, particularmente os
nematodes, como bioindicadores que permitam avaliar perturbações provocadas pela
presença de uma espécie alóctone.
O principal objetivo desta investigação foi verificar as respostas estruturais e funcionais
das comunidades de meiofauna perante a presença de um bivalve não-indígena. Este
objetivo foi atingido através da comparação de padrões de densidade, diversidade e
composição trófica das comunidades de meiofauna, especialmente os nematodes, em
locais com diferentes abundâncias de R. philippinarum. Todas as análises realizadas
mostraram que a densidade, os padrões de distribuição, diversidade e a composição
trófica das comunidades de nematodes foram estruturados principalmente por fatores
ambientais como o tipo de sedimento e a salinidade e não tanto pelas densidades de R.
philippinarum; Effects of the non-indigenous bivalve Ruditapes philippinarum
on meiofaunal communities of the Tagus estuary.
|ABSTRACT:
Meiofauna are presently regarded as very suitable organisms to monitor potential
ecological effects of natural and anthropogenic disturbances in aquatic ecosystems.
The presence of the non-indigenous bivalve R. philippinarum in the Tagus estuary
presented the opportunity to evaluate the ability of meiofauna communities,
specifically nematodes, as indicators to assess disturbances promoted by an
allochthonous species.
This research focused on the benthic meiofauna assemblages response to the presence
of a non-indigenous bivalve. Density, diversity and trophic composition patterns of the
meiofauna communities, particularly nematodes were examined along the estuary
gradient and related to environmental conditions and the occurrence of R.
philippinarum. All the performed analysis showed that nematodes density, distribution
patterns, diversity and trophic composition were mainly structured by distinct
environmental factors like sediment grain size and salinity rather than by R.
philippinarum densities
Challenging the drug-likeness dogma for new drug discovery in Tuberculosis
The emergence of multi- and extensively drug resistant tuberculosis worldwide poses a great threat to human health and highlight the need to discover and develop new, effective and inexpensive antituberculosis agents. High-throughput screening assays against well-validated drug targets and structure based drug design have been employed to discover new lead compounds. However, the great majority fail to demonstrate any antimycobacterial activity when tested against Mycobacterium tuberculosis in whole-cell screening assays. This is mainly due to some of the intrinsic properties of the bacilli, such as the extremely low permeability of its cell wall, slow growth, drug resistance, drug tolerance, and persistence. In this sense, understanding the pathways involved in M. tuberculosis drug tolerance, persistence, and pathogenesis, may reveal new approaches for drug development. Moreover, the need for compounds presenting a novel mode of action is of utmost importance due to the emergence of resistance not only to the currently used antituberculosis agents, but also to those in the pipeline. Cheminformatics studies have shown that drugs endowed with antituberculosis activity have the peculiarity of being more lipophilic than many other antibacterials, likely because this leads to improved cell penetration through the extremely waxy mycobacterial cell wall. Moreover, the interaction of the lipophilic moiety with the membrane alters its stability and functional integrity due to the disruption of the proton motive force, resulting in cell death. When a ligand-based medicinal chemistry campaign is ongoing, it is always difficult to predict whether a chemical modification or a functional group would be suitable for improving the activity. Nevertheless, in the "instruction manual" of medicinal chemists, certain functional groups or certain physicochemical characteristics (i.e., high lipophilicity) are considered red flags to look out for in order to safeguard drug-likeness and avoid attritions in the drug discovery process. In this review, we describe how antituberculosis compounds challenge established rules such as the Lipinski's "rule of five" and how medicinal chemistry for antituberculosis compounds must be thought beyond such dogmatic schemes.publishersversionpublishe
Redes e polarização urbana e financeira: uma exploração inical para o Brasil
This paper aims, in an exploratory way, to discuss the regional network of financial services in Brazil and its role in the configuration of the Brazilian urban network and its hierarchy. To achieve this objective, the paper, based on the seminal works of both CHRISTALLER (1966) and LÖSCH (1944/54), tries to understand how the process of spatial urban configuration works. Based on this framework it is possible to focus on the financial system, especially on the factors that determine the locational decision of financial institutions, aiming the building of a polarization system of the financial activities. The paper will adopt a adapted gravitation model to analyze the power of attraction of different financial centers based on diverse variables (credit, total assets, functional and structural diversification).polarization, financial system, centrality, urban network
Effect of oral creatine supplementation in soccer players metabolism. (Efecto de la ingesta de un suplemento de creatina en el metabolismo de jugadores de fútbol.)
<b>Abstract</b><p align="justify">The aim of the present study was to assess whether creatine can alter the metabolism of nitrogen compounds and performance in professional soccer players. The subjects were randomly divided into 2 groups: experimental (E; n = 17) and control (C; n = 14). Their initial evaluations included blood tests and nutritional intake. They then received a supplement consisting of 20 individual doses of creatine to be taken orally for 5 days, totaling 0.6 g.Kg-1 body weight per day (group E = 50% creatine + 50% dextrose; group C = 100% dextrose). On day 5, blood was collected from the resting subjects (PRE), and then 10 min (POST10) and 20 min (POST20) after they underwent an ergometric test. Nitrogen compounds and hematocrit were measured in each blood sample. There were no differences among the groups in the results of the physical examination, nutritional state, blood samples or performance. Serum ammonia levels measured after exercise were equal to those at rest. Serum urea increased in POST10 and POST20. In Group E, uremia was lower than in Group C in PRE, POST10 and POST20, indicating retention of protein and nucleotides.</p><b>Resumen</b><p align="justify">Este estudio objetiva determinar si la creatina puede alterar el metabolismo de los compuestos del nitrógenoy el desarrollo atlético en jugadores profesionales del fútbol. Los individuos fueron divididos aleatoriamenteen 2 grupos: experimental (E; n = 17) y control (C; n = 14). Sus análisis de sangre incluidos evaluaciones iniciales y producto alimenticio. Entonces recibieron un suplemento que consistía en 20 dosis individuales decreatina que se tomará oral por 5 días, sumando 0.6 g.Kg-1.peso corpóreo por el día (grupo E = 50% creatina+ 50% dextrosa; grupo C = 100% dextrosa). El el día 5, la sangre fue recogida a partir de los idividuos (PRE), y entonces de 10 minutos (POST10) y de 20 minutos (POST20) después de que experimentaran un test de esfuerzo máximo (GXT). Los compuestos del nitrógeno y el hematocrit fueron medidos en cada muestra de la sangre. No había diferencias entre los grupos en los resultados de la examinación física, del estado alimenticio, de las muestras de la sangre o del desarrollo atlético. Los niveles del amoníaco del suero midieron después de que el ejercicio fuera igual en descanso. La urea del suero aumentó de POST10 y de POST20. En el grupo E, la uremia era más baja que en el grupo C adentro PRE, POST10 y POST20, indicando la retención de la proteína y de los nucleotides.</p
The Coefficient Of Friction In Parkinson's Disease Gait
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)This study aimed to characterize the coefficient of friction (COF) curves of patients with Parkinson's disease (PD) during barefoot gait and to evaluate the relationships between this variable and functional scales. Twenty- two subjects with PD (ON phase of levodopa) and 22 healthy subjects participated in this study. The participants walked barefoot along a pathway that went over two force plates embedded in the floor of the data collection room. The instantaneous COF was calculated as the ratio between the horizontal and vertical components of the ground reaction forces. Two-sample t-tests applied to every 1% of the support phase of the COF curve were used to compare the groups and to identify the phases in which the two groups were different. Specifically, three COF areas were computed: Area 1 (for the loading response phase), Area 2 (for the midstance phase) and Area 3 (for the terminal stance phase). Pearson's tests were applied to assess the associations between the COF curve areas and the clinical scales. The subjects with PD exhibited lower COF values during the loading response and terminal stance phases and higher COF values during the mid-stance phase compared with the control group. A strong positive correlation was observed between Area 1 and the Timed Up and Go Test (90.3%). In conclusion, the patients' COFs exhibited patterns that were different from those of the control group. Moreover, during the loading response phase, these differences were well-correlated with the Timed Up and Go Test scale data; Timed Up and Go Test data can be used to identify the risk of falls among PD patients.3211722CAPES [BEX 11241/13-6]CNPqCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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