1,471,099 research outputs found
Anthropometric and physiological changes in elite female water polo players during a training year
No full textThe aim of the current study was to monitor physiological and anthropometric characteristics of elite female water polo players within the periodized training year. Fourteen subjects participated in the current study. However, only six subjects (Mean ± SD: Age 22.8 ± 3.7 years, Height 171.0 ± 10.8 cm, Body Mass 66.3 ± 4.7 kg) completed all sessions and thus were used for subsequent analyses. Subjects undertook testing in the general preparation, specific preparation and competition phases, with the final session being during the peaking component of the competition phase. Laboratory-based physiological measurements comprised peak oxygen uptake, anaerobic power, leg power, strength and flexibility, while anthropometric measurements included body fat percentage. Sport-specific tests involved the Multistage Swimming Shuttle Test (MSST) and the 30-second crossbar jumps. A repeated measures ANOVA revealed significant differences between testing sessions for body mass (F3,15 = 4.025, P = 0.028), body fat (F3,15 = 9.194, P = 0.001), MSST (F3,15 = 5.050, P = 0.017) and crossbar jumps (F2,10= 16.034, P = 0.001). No statistically significant differences were found for any other variables. The results of the study suggest that changes in anthropometric characteristics and performance parameters of elite female water polo players over a periodized training year occur with no changes in laboratory-based physiological measurements
Phosphorylation of mitotic kinesin-like protein 2 by polo-like kinase 1 is required for cytokinesis
No full textWe have investigated the function of mitotic kinesin-like protein (MKlp) 2, a kinesin localized to the central spindle, and demonstrate that its depletion results in a failure of cleavage furrow ingression and cytokinesis, and disrupts localization of polo-like kinase 1 (Plk1). MKlp2 is a target for Plk1, and phosphorylated MKlp2 binds to the polo box domain of Plk1. Plk1 also binds directly to microtubules and targets to the central spindle via its polo box domain, and this interaction controls the activity of Plk1 toward MKlp2. An antibody to the neck region of MKlp2 that prevents phosphorylation of MKlp2 by Plk1 causes a cytokinesis defect when introduced into cells. We propose that phosphorylation of MKlp2 by Plk1 is necessary for the spatial restriction of Plk1 to the central spindle during anaphase and telophase, and the complex of these two proteins is required for cytokinesis
STIL binding to Polo-box 3 of PLK4 regulates centriole duplication
No full textPolo-like kinases (PLK) are eukaryotic regulators of cell cycle progression, mitosis and cytokinesis; PLK4 is a master regulator of centriole duplication. Here, we demonstrate that the SCL/TAL1 interrupting locus (STIL) protein interacts via its coiled-coil region (STIL-CC) with PLK4 in vivo. STIL-CC is the first identified interaction partner of Polo-box 3 (PB3) of PLK4 and also uses a secondary interaction site in the PLK4 L1 region. Structure determination of free PLK4-PB3 and its STIL-CC complex via NMR and crystallography reveals a novel mode of Polo-box-peptide interaction mimicking coiled-coil formation. In vivo analysis of structure-guided STIL mutants reveals distinct binding modes to PLK4-PB3 and L1, as well as interplay of STIL oligomerization with PLK4 binding. We suggest that the STIL-CC/PLK4 interaction mediates PLK4 activation as well as stabilization of centriolar PLK4 and plays a key role in centriole duplication
Comparison of two anaerobic water polo-specific tests with the Wingate test
No full textThe purpose of the current study was to compare 2 water polo–specific tests—the 14 3 25-m swims (SWIM) and the 30-second crossbar jumps (30CJ)—with a laboratory-based test of anaerobic power, the Wingate Anaerobic Test (WAnT). Thirteen elite women’s water polo players (mean 6 SD: age 22.0 6 4.4 years, height 168.7 6 7.9 cm, body mass 65.9 6 6.1 kg, body fat 23.6 6 3.5 %, maximum oxygen uptake 51.4 6 4.5 mlkg21min21) participated in the study. The SWIM involved 14 repeated ‘‘all-out’’ sprints every 30 seconds. Swimming time was recorded, and sprint velocity, mean velocity (Vmean), and the gradient of the linear regression equation (GRADIENT) were calculated. The 30CJ involved repeated in-water water polo jumps and touching the goal crossbar with both hands. The number of touches in 30 seconds was recorded. Additionally, the subjects completed a 30-second WAnT, and mean power (Mp) and fatigue index (FI) were calculated. Kendall tau (t) rank correlation was used to examine for correlation between ranks. Significance level was set at p # 0.05. No significant correlation was found between any of the measures of the WAnT and the 2 sport-specific tests. It was suggested that the WAnT may not be an appropriate evaluation tool for anaerobic power assessment of water polo players, stressing the importance of sport-specific tests
COORDENADOR DE POLO: UMA DISCUSSÃO ACERCA DOS CONHECIMENTOS NECESSÁRIOS À UMA BOA GESTÃO
No full textO presente trabalho tem como objetivo apresentar e discutir uma série de competências complementares às exigidas legalmente que auxiliarão a figura do Coordenador de Polo no processo de gerenciamento de um Polo de Apoio Presencial. Entende-se que, apenas com os pré-requisitos mínimos exigidos por lei, que privilegiam os aspectos acadêmicos em detrimento de conhecimentos de práticas de gestão, os Coordenadores de Polo podem não se mostrar preparados para o exercício de suas funções. Desta forma, num cenário de expressivo crescimento de cursos de Educação a Distância (EaD), não tendo as competências técnicas necessárias, os coordenadores de Polos poderão não suprir as necessidades do Polo, conseqüentemente, não atenderão as expectativas, demandas e necessidades dos alunos, professores e da própria comunidade. Sugere-se, então, alguns processos de gestão que poderão auxiliá-los em suas tarefas, a saber: gestão estratégica, gestão da infra-estrutura, gestão de pessoas, gestão de processos, gestão de marketing. Os pré-requisitos básicos para a contratação de um coordenador de Polo não exigem, a certificação dos conhecimentos nas áreas de gestão, mas a necessidade imposta pelo meio, cada vez mais requer tais conhecimentos
On the regulation of centriole duplication in human cells : exploring the interactions of polo-like kinase 4 with the centrosomal proteins Cep192 and STIL
No full textCentrioles duplicate once in each cell cycle to give rise to two centrosomes that form the spindle poles during mitosis. Aberrant centriole duplication can result in the formation of supernumerary centrosomes, leading to incorrect spindle assembly and chromosome segregation errors, thereby possibly contributing to carcinogenesis (Ganem et al., 2009; Nigg, 2002; Zyss and Gergely, 2008). Thus, to ensure genome stability, centriole duplication has to be precisely regulated. Polo-like kinase 4 (PLK4) is a key regulator of centriole duplication (Bettencourt-Dias et al., 2005; Habedanck et al., 2005). PLK4 is characterized by an N-terminal Ser/Thr kinase domain and three C-terminal Polo-boxes (PB1-PB3) (Slevin et al., 2012). The PB1-PB2 domain is required for PLK4's centrosomal localization and binding to Cep152 (Cizmecioglu et al., 2010; Hatch et al., 2010; Slevin et al., 2012). In contrast to PB1-PB2, no binding partners have been described for PB3.
Here, we identify Cep192 and STIL as novel interaction partners of PLK4-PB1-PB2 and PLK4-PB3, respectively. In the first part of this study, we reveal that Cep192 directly binds PB1-PB2 via a short region within its N-terminus, which contains conserved patches of acidic residues. We show that also in the case of Cep152 a short N-terminal acidic region is critical for the binding to PB1-PB2. These acidic regions of Cep192 and Cep152 enable electrostatic interactions with positively charged residues of the PB1-PB2 domain in order to promote PLK4 centriolar recruitment (Sonnen et al., 2013). In the second part of this study, we identify STIL as the first known binding partner of PLK4-PB3. We show that the coiled-coil motif of STIL (STIL-CC) is necessary and sufficient for this interaction and thus important for centriole duplication. Based on a collaboration for crystallographic and NMR analyses, we furthermore demonstrate that PB3 adopts a canonical PB fold, and that the PLK4-PB3/STIL-CC binding mimics coiled-coil formation. Analysis of structure-guided STIL mutants suggests a dual binding mode of STIL-CC to PB3 and L1 of PLK4 (linker between the catalytic domain and the PB domains). Taken together, we propose a speculative model for the initial steps of procentriole assembly according to which PLK4 is recruited to centrioles by electrostatic interactions between PB1-PB2 and Cep192/Cep152, and thereafter is stabilized and activated via STIL-CC binding to PB3 and L1
O polo de apoio presencial e o desenvolvimento socioeconômico: uma leitura do entorno
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia e Gestão do Conhecimento, Florianópolis, 2015.A expansão da Educação a Distância no Brasil acontece de forma constante. Através de sua principal característica, na qual professores e alunos estão separados no tempo e no espaço físico, torna-se necessária a criação dos polos de apoio presencial. Com a implantação dos polos, além da oportunidade de acesso ao ensino superior, percebe-se a promoção do desenvolvimento socioeconômico na comunidade em que o mesmo foi implantado. Nesse sentido, esta dissertação tem como objetivo identificar os fatores de transformação no desenvolvimento socioeconômico provocado no entorno do polo de apoio presencial após sua implantação. Para a realização da pesquisa, quanto aos objetivos, classificou-se como descritiva e exploratória. A abordagem adotada para a análise dos dados foi a qualitativa e quantitativa e, para a coleta de dados foi realizado levantamento bibliográfico, documental e aplicação de questionário. O método de análise de dados da pesquisa foi o dedutivo. Os participantes da pesquisa foram coordenadores de polo de apoio presencial do Estado de Santa Catarina que oferecem cursos na modalidade a distância através do Sistema UAB. Após a organização dos dados coletados, os mesmos foram analisados de forma dedutiva, no qual foi possível observar que, independente do índice de desenvolvimento humano do município as organizações produtivas locais sofreram algum tipo de mudança após a implantação do polo. Constatou-se que fatores como o acesso ao ensino superior público, a oportunidade de formação profissional e o crescimento econômico ocasionados após a presença do polo, refletiram no desenvolvimento socioeconômico do seu entorno. Por fim, considera-se que a disseminação do conhecimento, ocasionada pela implantação do polo de apoio presencial, contribui para que a comunidade local adquira um novo olhar sobre o polo, reconhecendo este como elemento que contribui para o desenvolvimento socioeconômico local.Abstract : The expansion of the Distance Education in Brazil happens steadily. Through its main feature, in which teachers and students are separated in time and physical space, it is necessary to create the ad hoc support poles. With the implementation of the poles, and the opportunity to access to higher education, the promotion of socio-economic development is perceived in the community in which it was implemented. In this sense, this work aims to identify the factors of transformation in the socioeconomic development caused surrounding the presence support pole after its implementation. For the research, the aims, was classified as descriptive and exploratory. The approach adopted for the analysis of data was qualitative and quantitative, and for data collection was performed literature review, document and questionnaire. The method of research data analysis was deductive. Survey participants were engineers on-site support pole of the State of Santa Catarina offering courses in the distance through the UAB System. After the organization of the data collected, they were analyzed as deductions, in which it was observed that, regardless of the human development index of the municipality local productive organizations experienced some sort of change after the implementation of polo. It was found that factors such as access to public higher education, vocational training opportunities and caused economic growth after the presence of polo, reflected in socio-economic development of their surroundings. Finally, it is considered that the dissemination of knowledge, caused by the deployment of classroom support pole, contributes to the local community acquires a new look at the pole, recognizing this as an element that contributes to local socio-economic development
Polo like kinase 2 tumour suppressor and cancer biomarker: new perspectives on drug sensitivity/resistance in ovarian cancer
No full textThe polo-like kinase PLK2 has recently been identified as a potential theranostic marker in the management of chemotherapy sensitive cancers. The methylation status of the PLK2 CpG island varies with sensitivity to paclitaxel and platinum in ovarian cancer cell lines. Importantly, extrapolation of these in vitro data to the clinical setting confirms that the methylation status of the PLK2 CpG island predicts outcomes in patients treated with carboplatin and paclitaxel chemotherapy. A second cell cycle regulator, p57Kip2, is also subject to epigenetic silencing in carboplatin resistance in vitro and in vivo, emphasising that cell cycle regulators are important determinants of sensitivity to chemotherapeutic agents and providing insights into the phenomenon of collateral drug sensitivity in oncology. Understanding the mechanistic basis and identification of robust biomarkers to predict collateral sensitivity may inform optimal use of chemotherapy in patients receiving multiple lines of treatment
Marco Polo e le città invisibili.
No full textIl contributo rilegge alla luce del viaggio di Marco Polo il romanzo di Italo Calvino "Le città invisibili"
Eddie Polo
No full textPostcard portrait of the silent movie star and stuntman Eddie Polo (1875-1961) included in a supplement to Cinema Chat magazine
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