Variation in perceived collective efficacy among adolescent basketball players across 4-month competitive season.

A team shared belief in its capability to organize and execute some actions required to achieve given performance level is referred as collective efficacy. Collective efficacy in sports appears to be dependent on the interactions and organized dynamics between the players within the team, their competences, including physical competence, organization, structure and strategies. It is directly related to team performance potential. In the present study we examined the changes of perceived collective efficacy among young basketball players and 10 to 17 years across a 4-month competitive season, accounting for variation by age group since youth sports are generally organized by competitive age groups. Based on the repeated measures across 4 months in the range of age observed, we explored the trends of perceived collective efficacy among this sample players. Sixty-five adolescent male basketball players aged 13,7 (9,5 to 17,3) years at baseline were considered. Collective Efficacy Questionnaire for Sports (CEQS) was used to assess players´ perception of collective efficacy. The adolescent basketball players had high CEQS scores. Except for persistence, all CEQS factors did not vary by age group. However, no distinct trend of differences between age group was present. The CEQS factors remained high after 4-months competitive season exposure, except for ability where there was a systematic decrease for players scores at end-season.  A negative trend of change was apparent for persistence, preparation and unity as players were closer to late adolescence years. The results in this study highlight the importance for coaches and practitioners to consider environment and context influence on young basketball players´ collective efficacy perception.La creencia compartida de un equipo en su capacidad de organización y ejecución de acciones necesarias para alcanzar datos niveles de desempeño es referida como eficacia colectiva. La eficacia colectiva en el deporte parece depender de interacciones y dinámicas organizadas entre jugadores dentro de un equipo, sus competencias, incluyendo habilidades físicas, organización, estructura y estrategias. Está directamente relacionada con el potencial de rendimiento del equipo. En el presente estudio, examinamos los cambios en la eficacia colectiva percibida entre jóvenes jugadores de baloncesto de 10 a 17 años en cuatro meses de la temporada de competición, considerando la variación por grupo de edad así como generalmente las competiciones de jóvenes se organizan. Basado en medidas repetidas en cuatro meses en la amplitud de las edades observadas, exploramos las tendencias de la eficacia colectiva percibida entre los jugadores de esa muestra. Sesenta y cinco adolescentes jugadores de baloncesto del sexo masculino, con edad de 13,7 (9,5 a 17,3) años en la primera colecta fueron considerados. El Cuestionario de Eficacia Colectiva en los Deportes (CEQS) fue utilizado para medir la percepción de eficacia colectiva de los jugadores. Los jugadores tuvieron altas puntuaciones en el CEQS. Con excepción de la persistencia, todos los factores del CEQS no variaron de acuerdo con el grupo de edad. Sin embargo, ninguna tendencia distinta entre los grupos estuvo presente. Los factores del CEQS permanecieron elevados después de cuatro meses de exposición a la temporada competitiva, excepto por la habilidad donde hubo un descenso sistemático para las puntuaciones de los jugadores al final de la temporada. Una tendencia negativa de alteración fue aparente para persistencia, preparación y unión cuando jugadores estaban cerca de los últimos años de la adolescencia. Los resultados de este estudio destacan la importancia para los entrenadores y técnicos considerar el ambiente y la influencia del contexto en la percepción de eficacia colectiva en adolescentes jugadores de baloncesto.A crença compartilhada de uma equipe em sua capacidade de organização e execução de ações necessárias para atingirem dados níveis de desempenho é referida como eficácia coletiva. A eficácia coletiva no esporte parece ser dependente de interações e dinâmicas organizadas entre jogadores dentro de uma equipe, suas competências, incluindo competências físicas, organização, estrutura e estratégias. Está diretamente relacionada ao potencial de desempenho da equipe. No presente estudo, examinamos as alterações na eficácia coletiva percebida entre jovens jogadores de basquetebol de 10 a 17 anos em quatro meses da temporada de competição, considerando a variação por grupo etário assim como geralmente as competições de jovens são organizadas. Baseado em medidas repetidas em quatro meses na amplitude das idades observadas, exploramos as tendências da eficácia coletiva percebida entre os jogadores dessa amostra. Sessenta e cinco adolescentes jogadores de basquetebol do sexo masculino, com idade de 13,7 (9,5 a 17,3) anos na primeira coleta foram considerados. O Questionário de Eficácia Coletiva nos Esportes (CEQS) foi utilizado para mensurar a percepção de eficácia coletiva dos jogadores. Os jogadores tiveram altas pontuações no CEQS. Com exceção da persistência, todos os fatores do CEQS não variaram de acordo com o grupo etário. Contudo, nenhuma tendência distinta entre os grupos esteve presente. Os fatores do CEQS permaneceram elevados após quatro meses de exposição à temporada competitiva, exceto pela habilidade onde houve um decréscimo sistemático para as pontuações dos jogadores no final da temporada. Uma tendência negativa de alteração foi aparente para persistência, preparação e união quando jogadores estavam próximos dos últimos anos da adolescência. Os resultados desse estudo destacam a importância para treinadores e técnicos considerarem o ambiente e a influência do contexto na percepção de eficácia coletiva em adolescentes jogadores de basquetebol

Influence of age and maturation on perceived collective efficacy in youth basketball players

Growth and maturation impact the development of young athletes’ physique and function. It is likely that psychological and behavioral characteristics will also be impacted by maturity status. Perceived collective efficacy (CE) is a potential mediator of sports performance and may be influenciated by maturity status. Therefore, this study examined the perceived CE variation between young basketball players accounting for the influence of chronological age and biological maturity status. The sample included 57 adolescent basketball players aged 9.5 to 15.5 years. Chronological age, estimated age at peak height velocity (PHV) and CE through the Portuguese version of the Collective Efficacy Questionnaire for Sports were considered. Bayesian multilevel modeling was used to examine athletes’ perceived CE dimensions variation by maturity status and age. Overall, the adolescent basketball players’ perceived CE scores were high for all dimensions: ability (8.77±1.15); effort (9.20±1.03); persistence (8.87±1.18); preparation (8.96±1.08); unity (8.88±1.22). The variability estimates were very large, suggesting that the influence of maturity status on variation may be residual. There was no substantial relation between chronological age and the variation scores, although the results suggest that perceived variation was independent of chronological age variation and between players variation in maturity status. Further study examining the relations of growth, functional performance development, and perceived CE would be relevant for the holistic understanding of young basketball players’ development.O crescimento e a maturação afetam o desenvolvimento físico, a função e o comportamento de jovens atletas. É provável que características psicológicas e comportamentais também sejam afetadas pelo estágio maturacional. A eficácia coletiva (EC) percebida é um potencial mediador do desempenho esportivo e também pode ser influenciada pelo estágio maturacional. Portanto, este estudo examinou a variação da EC entre jovens jogadores de basquetebol, considerando a influência da idade cronológica e do estágio maturacional. Foram considerados e analisados em sua idade cronológica, na idade estimada no pico de velocidade de crescimento (PHV) e na EC 57 atletas de basquetebol adolescentes com idades entre 9,5 e 15,5 anos por meio da versão portuguesa do Questionário de Eficácia Coletiva para Esportes. Uma série de modelos Bayesianos de regressão linear multinível foi utilizada para estimar a EC percebida pelos atletas de acordo com seus estágios maturacionais e idade cronológica. No geral, os escores de EC dos jovens atletas de basquetebol foram elevados em todas as dimensões: capacidade (8,77±1,15); esforço (9,20±1,03); persistência (8,87±1,18); preparação (8,96±1,08); unidade (8,88±1,22). As estimativas de variabilidade foram muito grandes, sugerindo que a influência do estágio maturacional sobre a EC seja residual. Não houve relação substancial entre a idade cronológica e os escores de EC, embora os resultados sugiram que a EC percebida tenha sido independente da variação da idade cronológica e da variação nos estágios maturacionais entre os atletas. Estudos adicionais que examinem as relações entre crescimento, desenvolvimento de desempenho funcional e percepção de EC seriam relevantes para a compreensão holística do desenvolvimento de jovens jogadores de basquetebol

Exercise training in the aerobic/anaerobic metabolic transition prevents glucose intolerance in alloxan-treated rats

<p>Abstract</p> <p>Background</p> <p>Ninety percent of cases of diabetes are of the slowly evolving non-insulin-dependent type, or Type 2 diabetes. Lack of exercise is regarded as one of the main causes of this disorder. In this study we analyzed the effects of physical exercise on glucose homeostasis in adult rats with type 2 diabetes induced by a neonatal injection of alloxan.</p> <p>Methods</p> <p>Female Wistar rats aged 6 days were injected with either 250 mg/kg of body weight of alloxan or citrate buffer 0.01 M (controls). After weaning, half of the animals in each group were subjected to physical training adjusted to meet the aerobic-anaerobic metabolic transition by swimming 1 h/day for 5 days a week with weight overloads. The necessary overload used was set and periodically readjusted for each rat through effort tests based on the maximal lactate steady state procedure. When aged 28, 60, 90, and 120 days, the rats underwent glucose tolerance tests (GTT) and their peripheral insulin sensitivity was evaluated using the HOMA index.</p> <p>Results</p> <p>The area under the serum glucose curve obtained through GTT was always higher in alloxan-treated animals than in controls. A decrease in this area was observed in trained alloxan-treated rats at 90 and 120 days old compared with non-trained animals. At 90 days old the trained controls showed lower HOMA indices than the non-trained controls.</p> <p>Conclusion</p> <p>Neonatal administration of alloxan induced a persistent glucose intolerance in all injected rats, which was successfully counteracted by physical training in the aerobic/anaerobic metabolic transition.</p

Influence of HLA-DRB1 and HLA-DQB1 Alleles on IgG Antibody Response to the P. vivax MSP-1, MSP-3α and MSP-9 in Individuals from Brazilian Endemic Area

Background: the antibody response generated during malaria infections is of particular interest, since the production of specific IgG antibodies is required for acquisition of clinical immunity. However, variations in antibody responses could result from genetic polymorphism of the HLA class II genes. Given the increasing focus on the development of subunit vaccines, studies of the influence of class II alleles on the immune response in ethnically diverse populations is important, prior to the implementation of vaccine trials.Methods and Findings: in this study, we evaluated the influence of HLA-DRB1* and -DQB1* allelic groups on the naturally acquired humoral response from Brazilian Amazon individuals (n = 276) against P. vivax Merozoite Surface Protein-1 (MSP-1), MSP-3 alpha and MSP-9 recombinant proteins. Our results provide information concerning these three P. vivax antigens, relevant for their role as immunogenic surface proteins and vaccine candidates. Firstly, the studied population was heterogeneous presenting 13 HLA-DRB1* and 5 DQB1* allelic groups with a higher frequency of HLA-DRB1*04 and HLA-DQB1*03. the proteins studied were broadly immunogenic in a naturally exposed population with high frequency of IgG antibodies against PvMSP1-19 (86.7%), PvMSP-3 (77%) and PvMSP-9 (76%). Moreover, HLA-DRB1*04 and HLA-DQB1*03 alleles were associated with a higher frequency of IgG immune responses against five out of nine antigens tested, while HLA-DRB1* 01 was associated with a high frequency of non-responders to repetitive regions of PvMSP-9, and the DRB1*16 allelic group with the low frequency of responders to PvMSP3 full length recombinant protein.Conclusions: HLA-DRB1*04 alleles were associated with high frequency of antibody responses to five out of nine recombinant proteins tested in Rondonia State, Brazil. These features could increase the success rate of future clinical trials based on these vaccine candidates.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Yerkes National Primate Research Center BaseNational Center for Research Resources of the National Institutes of HealthNIHCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Inst Oswaldo Cruz, Lab Immunoparasitol, BR-20001 Rio de Janeiro, BrazilOswaldo Cruz Fdn Fiocruz, Ctr Technol Dev Hlth CDTS, Rio de Janeiro, BrazilInst Oswaldo Cruz, Lab Simulideos & Oncocercose, BR-20001 Rio de Janeiro, BrazilEmory Univ, Emory Vaccine Ctr, Atlanta, GA 30322 USAUniv Estado Rio de Janeiro, Histocompatibil & Cryopreservat Lab, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, Ctr Terapia Celular & Mol CTCMol, Escola Paulista Med, São Paulo, BrazilEmory Univ, Sch Med, Div Infect Dis, Atlanta, GA USACDC Natl Ctr Infect Dis, Div Parasit Dis, Atlanta, GA USAUniversidade Federal de São Paulo, Ctr Terapia Celular & Mol CTCMol, Escola Paulista Med, São Paulo, BrazilFAPESP: 2009/15132-4Yerkes National Primate Research Center Base: RR00165NIH: RO1 AI0555994Web of Scienc

Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains

Ruiz JC, D'Afonseca V, Silva A, et al. Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains. PLoS ONE. 2011;6(4): e18551.Background: Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity. Methodology and Findings: We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer. Conclusions: These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers CP001809 and CP001829

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost