A Physical Model of Zeno's Dichotomy     

Angel  Leonard 《The British journal for the philosophy of science》2001,52(2):347-358

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Primary Care and Laboratory Medicine—Frequently Asked Questions     

Joseph Lopez 《Indian journal of clinical biochemistry : IJCB》2012,27(1):105-106

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Timescales for exploratory tactical behaviour in football small-sided games     

Angel Ric  Robert Hristovski  Bruno Gonçalves  Lorena Torres  Jaime Sampaio  Carlota Torrents 《Journal of sports sciences》2016,34(18):1723-1730

The aim of this study was to identify the dynamics of tactical behaviour emerging on different timescales in football small-sided games and to quantify short- and long-term exploratory behaviour according to the number of opponents. Two teams of four professional male footballers played small-sided games against two different teams with a variable number of opponents (3, 5 and 7). Data were collected using a combination of systematic observation and a non-differential global positioning system (15 Hz). The temporal diversity and structural flexibility of the players were determined by calculating the dynamic overlap order parameter q, entropy and trapping strength. Analysis of the exploratory dynamics revealed two different timescales, forming a different metastable landscape of action for each constraint. Fast dynamics lasted on average a few seconds and consisted of changes in tactical patterns. The long timescale corresponded to the shared tasks of offence and defence lasting tens of seconds. The players’ tactical diversity decreased with an increasing number of opponents, especially in defence. Manipulating numerical imbalance is likely to promote changes in the diversity, unpredictability and flexibility of tactical solutions. The fact that the temporally nested structure of constraints shaped the emergence of tactical behaviour provides a new rationale for practice task design. The manipulation of numerical imbalance on the timescale of a few tens of seconds, on which the exploratory behaviour of players saturates, may help coaches to optimise the exploratory efficiency of the small-sided games.  相似文献   

Early Identification and Intervention: Head Start's Response to Mental Health Challenges     

Michael L. Lopez  Louisa B. Tarullo  Steven R. Forness  Cheryl A. Boyce 《Early education and development》2000,11(3):265-282

Serving low-income children from birth to age five and their families, Head Start is a primary venue for identification and intervention in the area of child mental health. However, recent research has demonstrated that the knowledge base regarding prevalence, developmental course, and predictive power of child mental health problems is lacking for young children in general and low-income, diverse populations in particular. Head Start's agency-level data is often discrepant from both national estimates and small, intensive studies of similar populations, perhaps for reasons related to availability of community services and professional staff, as well as concerns about stigmatization. Following on recent expert recommendations, new collaborative Federal initiatives are underway to increase our understanding of the types, trajectories, and treatments of mental health problems affecting the vulnerable children served by Head Start. The paper concludes with a call to action for the field in the area of young children's mental health.  相似文献   

Incentive learning and the motivational control of instrumental performance by thirst     

Matias Lopez  Bernard Balleine  Anthony Dickinson 《Learning & behavior》1992,20(4):322-328

The role of incentive learning in instrumental performance following a shift in the degree of water deprivation was analyzed in three experiments. In Experiments 1A and IB, rats trained to perform an instrumental action reinforced with either sucrose or maltodextrin solutions when in a high-deprivation state were subsequently shifted to a low-deprivation state and tested in extinction. This within-state shift in water deprivation reduced instrumental performance only when the animals had been exposed to the reinforcer in the low-deprivation state prior to instrumental training. In Experiment 2, a concurrent training procedure was used to assess whether the change in the value of the reinforcer brought about by preexposurewas mediated by the contingency between the instrumental action and the reinforcer. Preexposure to the reinforcer under the low-deprivation state produced a selective reduction of the performance of the action upon which it was contingent during training when testing was conducted in extinction following a shift from the high- to the low-deprivation state. These experiments provide evidence that animals have to learn about the incentive value of a reinforcer in a particular motivational state through exposure to the reinforcer in that state.  相似文献   

Effects of vanadate supplementation on high fat-diet and diabetes-induced metabolic changes in liver     

Subbiah Pugazhenthi  Joseph F. Angel  Ramji L. Khandelwal 《Indian journal of clinical biochemistry : IJCB》1996,11(2):108-114

Normal and streptozotocin-induced diabetic rats were fed the control high starch-diet or a high fatdiet supplemented with or without sodium orthovanadate (1.5 mg/g diet) for six weeks. Plasma glucose, insulin and triacylglycerol levels and the activities of hepatic glycogen synthase, phosphorylase, glucose-6-phosphate dehydrogenase, malic enzyme, and ATP-citrate lyase were measured in these eight groups of rats. The high fat-diet increased the levels of insulin (P<0.05) and triacylglycerol (P<0.01) in plasma and decreased the activities (P<0.001) of phosphorylase (active from and total) and the lipogenic enzymes. Vanadate supplementation led to significant (P<0.001) decreases in the elevated insulin and triacylglycerol levels whereas the enzyme activities remained unaffected. Diabetes and fat diet in combination caused 3.7-fold increases in plasma glucose and triacylglycerol levels and vanadate decreased them by 58% and 74% respectively. Vanadate improved the activities of hepatic glycogen metabolizing and lipogenic enzymes in diabetic rats when they were fed on control starch-diet but not with high fat-diet. This study shows that vanadate normalizes hyperinsulinemia and hypertriglyceridemia but not the defective hepatic glycogen metabolism in high fat-fed rats.  相似文献   

Cultural Beliefs and Disability: Implications for Rehabilitation Counsellors     

Quintin Boston  Paige N. Dunlap  Glacia Ethridge  Erin Barnes  Angel R. Dowden  Myshalae J. Euring 《International journal for the advancement of counseling》2015,37(4):367-374

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Supporting child and family resilience in the face of political violence: Evidence from a home visit parenting program     

Jane Leer  Florencia Lopez Boo  Savannah Norman 《Child development》2023,94(5):1222-1238

Political violence affects more than 25% of children globally, yet little is known about how to support positive adaptation among conflict-affected children. Using a sample of 3797 Nicaraguan child-caregiver dyads (M_AgeTime1 = 1.5 years, M_AgeTime2 = 5.9 years; 51% male), this registered report used a novel quasi-experimental approach to examine how exposure to political violence relates to child and caregiver outcomes, and to test three policy-relevant moderators: participation in a large-scale home visit parenting program, household economic disruption, and media exposure. Results revealed positive associations between political violence and harsh discipline practices (0.33 SD), but there was no evidence that political violence affected children's behavior, caregiver depressive symptoms, or responsive parenting practices, and there was no evidence of moderation.  相似文献   

Coco Solo: Desde la fiesta de sol hasta el marmolero     

Osvaldo Lopez 《International journal of qualitative studies in education》2013,26(2):149-165

Estos cuentos pertenecen al libro en preparacion Paso en el barrio y tratan sobre hechos ocurridos en un pequeño barrio marginal de La Habana llamado Coco Solo. Los personajes que aqu í aparecen son reales. Los sucesos que se cuentan en su mayoría también lo son. Muchas situaciones que parecen ser surrealistas ocurrieron ciertamente. La imaginación popular, la transmisión de las historias de una generación a otra o la fantasía del autor también están presente, pero siempre basadas en lo que pasó en el barrio.  相似文献   

Confirmatory factor analysis of the Values Aspired for the Future Scale in grandparents     

C. Noriega  C. Velasco  J. Lopez 《Educational gerontology》2017,43(5):248-258

Although the engagement of grandparents in grandchildren’s life has increased, there is a lack of research that explores the values that grandparents desire to transmit to their grandchildren. The aim of this study was to analyze the factor structure, the validity, and the reliability of the Values Aspired for the Future Scale in a sample of grandparents. Three hundred grandparents participated in this study. Confirmatory factor analysis showed a three-factor structure with an excellent overall fit: personal and relationship values, abilities and knowledge values, and materialistic values. Grandparents’ sex did not have a moderating effect on the factor structure. An adequate internal consistency was obtained. Signi?cant associations between values, health-related quality of life, social support, and psychological well-being were found, with the exception of the materialistic values. This scale should be tested in different cultural contexts in order to confirm the results found. The implications of the results are discussed.  相似文献