Potential financial loss and risk factors for hamstring muscle injuries in elite male Brazilian soccer players: a season-long prospective cohort pilot study.

Purpose: The aim of this pilot study was to analyze the potential financial loss and a range of potential risk factors for hamstring muscle injuries in elite Brazilian soccer. Methods: Thirty-four male players (age: 25 ± 6 years; stature: 180 ± 8 cm; body mass: 78 ± 9 kg; minutes played in matches: 2243 ± 1423 min) from an elite professional soccer club were monitored during a 12-month season. Muscle injury was identified by magnetic resonance imaging and the severity was defined according to the number of days away: minimal (1-3 days), mild (4-7 days), moderate (8-28 days), severe (>28 days). Potential financial loss due to the team's under achievements was determined. Dorsiflexion range of motion, eccentric knee flexor strength and isokinetic tests were performed during the pre-season. Association between dependent variables and the occurrence of injury was evaluated. Results: Nine hamstring muscle injuries with moderate severity were found in 8 athletes. Recovery time was 22 days off the field on average. Potential financial loss was $-43.2 million USD and earnings on merit money was 21%. Previous injury, increased flexor deficit 60°â€…/sec and increased flexor fatigue index 300°/sec were all associated with a greater chance of hamstring muscle injury. Ankle dorsiflexion range of motion was significantly lower in the injured group (35.6 ± 3° vs. 39.1 ± 4.9°; p = 0.017, effect size = -0.74). Conclusion: High financial burden was found in elite Brazilian soccer during one full season. Injured athletes had high hamstring fatigue index, knee flexor strength deficit, ankle range of motion restriction and previous hamstring muscle injury when compared to non-injured athletes. Therefore, preventive approaches in professional soccer players with previous hamstring injuries should be a priority.

Geographic intelligence to investigate community participation: a scoping review.

PURPOSE: To understand the applicability and unique contributions of global positioning system (GPS) and geographic information system (GIS) technologies to investigate individuals' participation in the community. METHODS: A scoping review was conducted to summarize studies that employed GPS and/or GIS to assess community participation. Systematic literature searches were performed using nine electronic databases, up to April 2022. Two independent reviewers screened studies for eligibility and extracted data from the selected studies. RESULTS: The searches retrieved 628 articles, of which 36 met the inclusion criteria. In 31 studies, a GPS unit or GPS-enabled device monitored the community mobility of individuals with different health conditions. Tracking periods varied from five hours to 30 consecutive days. The spatiotemporal parameters obtained from satellite-based data provided information about individuals' presence in the community. Most studies combined GPS with other measuring tools (self-report diaries/questionnaires, qualitative interviews) to capture a broader description of community participation. CONCLUSIONS: GPS and GIS are viable approaches for advancing research as they provide unique information about community participation not easily captured by other methods. The combination of available methods comprehensively address the physical and social dimensions of this construct.IMPLICATIONS FOR REHABILITATIONGlobal positioning system (GPS) and geographic information system (GIS) technology allows direct and real-time quantification of patterns of individuals' community mobility.The geographic area where individuals participate in daily living activities complements information from self-report diaries/questionnaires.Combining GPS technology with self-report diaries/questionnaires allows a broader description of individuals' community participation, addressing respectively both its physical and social dimensions.Knowledge of individuals' access to and involvement in community locations/situations may help therapists design interventions to improve community participation.

Smartphone-Based Platform for Secure Multi-Hop Message Dissemination in VANETs.

Vehicular ad-hoc Networks (VANETs) are recognized as a cornerstone of Intelligent Transportation Systems (ITS) to enable the exchange of information among vehicles, which is crucial for the provision of safety-related and entertainment applications. However, practical useful realizations of VANETs are still missing, mainly because of the elevated costs and the lack of a final standardization. In this regard, the feasibility of using smartphones as nodes in VANETs has been explored focusing on small-scale deployments to mainly validate single-hop communication capabilities. Moreover, existing smartphone-based platforms do not consider two crucial requirements in VANETs, namely, multi-hop communication and the provision of security services in the message dissemination process. Furthermore, the problem of securing message dissemination in VANETs is generally analyzed through simulation tools, while performance evaluations on smart devices have not been reported so far. In this paper, we aim to fill this void by designing a fully on-device platform for secure multi-hop message dissemination. We address the multi-hop nature of message dissemination in VANETs by integrating a location-based protocol that enables the selection of relay nodes and retransmissions criteria. As a main distinction, the platform incorporates a novel certificateless cryptographic scheme for ensuring data integrity and nodes' authentication, suitable for VANETs lacking of infrastructure.

Determinação altimétrica através do sistema de posicionamento global

This study aims at the influence on the data acquisition with GPS receivers in altimetric determination. The altimetric survey is carried out through the method of static relative thread, using two GPS receivers of one frequency, at different times of occupation (30, 15, 10, 5 minutes), with a recording level of two seconds. The altitudes obtained with receivers GPS are compared with the altitudes determined by trigonometrical leveling with Total Station. The results showed that the periods of occupation lower than 30 minutes (15, 10 and 5 minutes) are also appropriated to obtain the centimetric differences for the analyzed altitudes. Considering the accuracy of the conventional topographical methods, this study demonstrates the possibility of the precise use of the Global Positioning System (GPS) in altimetric surveys, if modeling of the geoidal undulation is also used.

Este estudo tem por objetivo verificar a influência do tempo de coleta de dados com receptores GPS nas determinações altimétricas. O levantamento altimétrico é realizado através do método de posicionamento relativo estático, utilizando dois receptores GPS de uma freqüência, em diferentes tempos de ocupação (30, 15, 10 e 5 minutos) com uma taxa de gravação de dois segundos. As altitudes obtidas com receptores GPS são comparadas com as altitudes determinadas por nivelamento trigonométrico com Estação Total. Os resultados mostraram que os tempos de ocupação menores que 30 minutos (15, 10 e 5 minutos) também são adequados para a obtenção de diferenças centimétricas nas altitudes analisadas. Mesmo considerando a precisão dos métodos topográficos convencionais, este estudo demonstra a possibilidade da utilização do Sistema de Posicionamento Global (GPS) de forma precisa nos levantamentos altimétricos, desde que se efetue a modelagem da ondulação geoidal.

Reconstituição de uma poligonal topográfica pelo sistema de posicionamento global: planimetria

The objective of this study is to verify the time influence of the GPS receivers for data acquisition in the reconstitution of a topographic polygonal. The determination of the polygonal is determined by the relative static positioning method using two of one frequency GPS receivers at different occupation periods of points (30,15, 10 and 5 minutes), with a two second recording rate. Results of the determination using GPS receivers are compared with the distances, azimuths, horizontal projections, horizontal angles, and the obtained areas of a polygon, on which the topographic elements of this polygon are determined by the perimetrical path using a Total Station. The angles of the polygon obtained by Total Station were calculated by the average of 24 readings and the distances by the average of 12 readings. The results show that the reconstitution of a topographic polygonal depends on the quality of the data collected with the GPS receivers, which are influenced by the time of the occupation points. The 15 minute' occupation time seems to be more appropriated, presenting a small difference (a few centimeters) with respect to the polygonal elements that were analyzed.

Este estudo tem por objetivo verificar a influência do tempo de coleta de dados com receptores GPS na reconstituição de uma poligonal topográfica. O levantamento da poligonal é realizado através do método de posicionamento relativo estático. São utilizados dois receptores GPS de uma freqüência, em diferentes tempos de ocupação dos pontos (30, 15, 10 e 5 minutos) com uma taxa de gravação de 2 s. Os resultados do levantamento com receptores GPS são comparados com as distâncias, azimutes, projeções horizontais, ângulos horizontais e as áreas obtidas de um polígono, cujos elementos topográficos foram determinados por caminhamento perimétrico utilizando uma Estação Total. Os ângulos do polígono levantado por Estação Total, foram calculados através da média de 24 leituras e as distâncias através da média de 12 leituras. Os resultados mostram que a reconstituição de uma poligonal topográfica depende da qualidade dos dados coletados pelos receptores GPS, sendo influenciada pelo tempo de ocupação dos pontos. O tempo de ocupação de 15 minutos demonstra ser o mais adequado para a obtenção de uma diferença centimétrica nos elementos da poligonal que são analisados.

Reconstituição de uma poligonal topográfica pelo sistema de posicionamento global: planimetria

The objective of this study is to verify the time influence of the GPS receivers for data acquisition in the reconstitution of a topographic polygonal. The determination of the polygonal is determined by the relative static positioning method using two of one frequency GPS receivers at different occupation periods of points (30,15, 10 and 5 minutes), with a two second recording rate. Results of the determination using GPS receivers are compared with the distances, azimuths, horizontal projections, horizontal angles, and the obtained areas of a polygon, on which the topographic elements of this polygon are determined by the perimetrical path using a Total Station. The angles of the polygon obtained by Total Station were calculated by the average of 24 readings and the distances by the average of 12 readings. The results show that the reconstitution of a topographic polygonal depends on the quality of the data collected with the GPS receivers, which are influenced by the time of the occupation points. The 15 minute' occupation time seems to be more appropriated, presenting a small difference (a few centimeters) with respect to the polygonal elements that were analyzed.

Este estudo tem por objetivo verificar a influência do tempo de coleta de dados com receptores GPS na reconstituição de uma poligonal topográfica. O levantamento da poligonal é realizado através do método de posicionamento relativo estático. São utilizados dois receptores GPS de uma freqüência, em diferentes tempos de ocupação dos pontos (30, 15, 10 e 5 minutos) com uma taxa de gravação de 2 s. Os resultados do levantamento com receptores GPS são comparados com as distâncias, azimutes, projeções horizontais, ângulos horizontais e as áreas obtidas de um polígono, cujos elementos topográficos foram determinados por caminhamento perimétrico utilizando uma Estação Total. Os ângulos do polígono levantado por Estação Total, foram calculados através da média de 24 leituras e as distâncias através da média de 12 leituras. Os resultados mostram que a reconstituição de uma poligonal topográfica depende da qualidade dos dados coletados pelos receptores GPS, sendo influenciada pelo tempo de ocupação dos pontos. O tempo de ocupação de 15 minutos demonstra ser o mais adequado para a obtenção de uma diferença centimétrica nos elementos da poligonal que são analisados.

Determinação altimétrica através do sistema de posicionamento global

This study aims at the influence on the data acquisition with GPS receivers in altimetric determination. The altimetric survey is carried out through the method of static relative thread, using two GPS receivers of one frequency, at different times of occupation (30, 15, 10, 5 minutes), with a recording level of two seconds. The altitudes obtained with receivers GPS are compared with the altitudes determined by trigonometrical leveling with Total Station. The results showed that the periods of occupation lower than 30 minutes (15, 10 and 5 minutes) are also appropriated to obtain the centimetric differences for the analyzed altitudes. Considering the accuracy of the conventional topographical methods, this study demonstrates the possibility of the precise use of the Global Positioning System (GPS) in altimetric surveys, if modeling of the geoidal undulation is also used.

Este estudo tem por objetivo verificar a influência do tempo de coleta de dados com receptores GPS nas determinações altimétricas. O levantamento altimétrico é realizado através do método de posicionamento relativo estático, utilizando dois receptores GPS de uma freqüência, em diferentes tempos de ocupação (30, 15, 10 e 5 minutos) com uma taxa de gravação de dois segundos. As altitudes obtidas com receptores GPS são comparadas com as altitudes determinadas por nivelamento trigonométrico com Estação Total. Os resultados mostraram que os tempos de ocupação menores que 30 minutos (15, 10 e 5 minutos) também são adequados para a obtenção de diferenças centimétricas nas altitudes analisadas. Mesmo considerando a precisão dos métodos topográficos convencionais, este estudo demonstra a possibilidade da utilização do Sistema de Posicionamento Global (GPS) de forma precisa nos levantamentos altimétricos, desde que se efetue a modelagem da ondulação geoidal.