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Rats confronted with the onset of a light gradient display a transient increase in locomotion called theactivity response (AR) and a dark preference (Godsil & Fanselow, 2004). These experiments demonstrate that the magnitude of the AR can be blunted
with Pavlovian fear-conditioning procedures via associative and nonassociative fear. Although manifested in decreased locomotion,
the blunted AR effect was not due to increased freezing or immobility behaviors. Instead, rats displayed reduced rearing and
an increase in a class of behaviors calledstationary activity. These results suggest that the lighting differential supplied by the cue influences the topography of defensive behavior
and reduces the expression of freezing. This procedure provides a means by which to examine learned and unlearned defensive
responses to the same stimulus. 相似文献
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M Martín-Matillas FB Ortega JR Ruiz D Martínez-Gómez G Vicente-Rodríguez A Marcos L Béghin A Kafatos M González-Gross M Zaccaria D Molnár S De Henauw M Sjöström LA Moreno MJ Castillo On Behalf Of The Helena Study 《Journal of sports sciences》2012,30(13):1329-1335
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?0.05); and mother's and sisters' physical activity engagement were positively associated with higher muscular strength in adolescents (P?0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P?0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents' physical activity. 相似文献
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Francisco P. Romero Ismael CaballeroJesus Serrano-Guerrero Jose A. Olivas 《Information processing & management》2012
Nowadays, new ways of managing and accessing to health-care information are continuously appearing. Web-based Personal Health Records (web PHRs) have the potential to make data about health-care available to clinicians, researchers and students in different medical contexts and applications. Therefore, the amount of web PHRs accessible through Internet has grown enormously and as a result health-care professionals are currently burdened with more and more data. It’s probable that these data, unfortunately, have not always the adequate levels of quality, making that their work cannot always be as successful as expected. As a way of alleviating this fact, the present work is focused on improving the document filtering results in the context of web PHRs management. To achieve this goal, a new kind of document filtering model is proposed. This model is based on fuzzy prototypes which are defined by means of conceptual prototypes. These prototypes are obtained by using a data quality analysis of documents. This analysis guarantees that filtered information will be relevant enough for the information user. The complete model provides an efficient strategy of document filtering that can be very useful when it is necessary to deal with a constant flow of new information. 相似文献