17 research outputs found
Health-related fitness as a predictor of anxiety levels among school adolescents: an observational cross-sectional study
Background:
There is an inverse association between cardiorespiratory fitness and general anxiety levels in adolescents. Obesity also is associated with a higher risk of anxiety in this population. However, little is known about the association between other health-related fitness elements with anxiety symptoms in this population. The authors explored the relationship between health-related fitness and anxiety symptoms in a large sample of Brazilian youth.
Methods:
This was an observational cross-sectional study with a sample comprised of 257 school adolescents, who were 136 girls (52.9%) and 121 boys (47.1%). The health-related fitness elements were evaluated by FitnessGram® test and anxiety levels by Multidimensional Anxiety Scale for Children - 39. Hierarchical regression analyses were used to determine the association between health-related fitness elements and anxiety symptoms in both sexes.
Results:
In male adolescents, only the cardiorespiratory fitness was significantly associated with anxiety symptoms (F(1, 119) = 6.472; P = 0.012; R2 = 0.052; adjusted R2 = 0.044). In turn, the anxiety symptoms showed an inverse small relationship with cardiorespiratory fitness (r = - 0.227; P < 0.01). However, in female adolescents, no association was found between health-related fitness elements and anxiety symptoms.
Conclusion:
The level of cardiorespiratory fitness may represent a marker of anxiety in male adolescents
On the typology and the worship status of sacred trees with a special reference to the Middle East
This article contains the reasons for the establishment of sacred trees in Israel based on a field study. It includes 97 interviews with Muslim and Druze informants. While Muslims (Arabs and Bedouins) consider sacred trees especially as an abode of righteous figures' (Wellis') souls or as having a connection to their graves, the Druze relate sacred trees especially to the events or deeds in the lives of prophets and religious leaders. A literary review shows the existence of 24 known reasons for the establishment of sacred trees worldwide, 11 of which are known in Israel one of these is reported here for the first time. We found different trends in monotheistic and polytheistic religions concerning their current worship of sacred trees
Evidence of Erroneous Deductions and their Possible Effects on the Initial Learning of the Concept of Cell in Primary School
En este trabajo se han obtenido evidencias sobre dificultades para procesar información referida al concepto de célula en estudiantes de escuela primaria. Se identificaron posibles deducciones erróneas que podrían establecer estudiantes de 5to grado (10-11 años) que intentaran procesar cognitivamente, y por primera vez, la información de libros de texto escolares y del discurso docente sobre el tema y se diseñó un cuestionario con el objetivo de hallar evidencia de estas deducciones. Fue posible detectar algunas evidencias de construcción de modelos explicativos incipientes siendo destacable la aparición de modelos consistentes, pero científicamente incorrectos. Luego, se aplicó el mismo cuestionario a estudiantes de 6to y 7mo grado (11-13 años) y se observó que algunos patrones de respuesta se mantenían e, incluso, se afianzaban. Estos modelos podrían dar cuenta del origen de errores o dificultades en la comprensión del concepto célula en estudiantes de niveles educativos subsiguientes.In this paper we have obtained some evidence on difficulties in processing information about the cell among primary school students. We identified possible misleading deductions that 5th grade students (10-11 years) could establish when trying, for the first time, to cognitively process information on the subject from school textbooks and teacher discourse, and we designed a questionnaire to find evidence of these deductions. It was possible to detect some evidence of incipient explanatory models. It is important to highlight the emergence of consistent but scientifically incorrect models. Then, the same questionnaire was applied to 6th and 7th grade students (11-13 years), and it was found that some response patterns prevailed and were even reinforced. These models could account for the origin of errors or difficulties in understanding the concept of cell among students of subsequent educational levels.Fil: Edelsztein, Valeria Carolina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación e Investigación en Enseñanza de las Ciencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Galagovsky, Lydia Raquel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Formación e Investigación en Enseñanza de las Ciencias; Argentin
Towards the development of an environmental rule-based model for predicting recruitment in Brazilian sardine Sardinella brasiliensis
A rule-based model was built in order to analyse the effects of environmental variables (wind stress, Ekman transport, turbulence, and sea surface temperature [SST]) on the recruitment of the Brazilian sardine Sardinella brasiliensis. The purpose of modelling was (1) to test the optimal environmental window hypothesis (characterised by ‘dome-shape' formats) for the variables studied and (2) to evaluate the application of the model as a tool for recruitment prediction. The model was run under different conditions and the following results were obtained: (1) when environmental variables only were used as inputs, the model response was poor; (2) when biomass was added as an input, and the dome-shape effect enhanced, the model's results were good; and (3) when the dome-shape effect was excluded, the model response was intermediate. These findings support the hypothesis of an ‘optimal environmental window' for wind and SST, and that incorporation of such relationships leads to better predictions of recruitment. Hence, although the model was calibrated with a relatively short time-series, it may prove to be a useful decision-support tool to define more flexible limits for allocation of fishing effort. Keywords: models, optimal environmental window, prediction, recruitment, rule-based, Sardinella, south-eastern BrazilAfrican Journal of Marine Science 2005, 27(3): 539–54
A System Dynamics Model for the Environmental Management of the Sepetiba Bay Watershed, Brazil
Gonzalez-Araya, M. C. Departmento de Modelación y Gestión Industrial, Facultad de Ingeniería, Universidad de Talca, Merced No. 437, Curicó, Chile.-In the recent past, the Sepetiba Bay watershed, located in the Rio de Janeiro State, Brazil has experienced rapid industrial development and population growth, as well as an increase in water pollution and environmental degradation. To analyze the complex interrelationships among the agents affecting the Sepetibza Bay environment, a system dynamics model was developed. The model builds on extensive studies conducted for the watershed, and simulates different hypotheses of economic growth and of demographic expansion. Thus, it can be used as a decision support tool for the identification of investment priorities and policy analyses under various scenarios. In order to provide a comprehensive approach to the environmental management of the Sepetiba Bay watershed, the model had to consider only the most relevant aspects of the behavior and the key interactions among agents operating in the watershed. In this article, the model’s structure is presented together with some of its main results
Virtual simulation of a nuclear power plant's control room as a tool for ergonomic evaluation
a b s t r a c t This research deals with the virtual modeling and ergonomic evaluation of a PWR NPP control room, aiming specially with the assessing of the elapsed times spent by operators to control such safe-critical system. Secure Nuclear power plant (NPP) operation involves using guidelines that specify procedures to be followed by personnel. Control rooms' environments, though, present complex features and a series of mechanisms unpredicted by the guidelines, which must be faced accordingly. All these must be considered in ergonomics evaluations of NPP control rooms. This work proposes the use of virtual simulation through reusing a game engine platform, in which the real environment may be virtually modeled and people are able to virtually navigate and interact among themselves, to support ergonomics evaluation in adequating control rooms for licensing of NPPs. Virtual experiments results were very similar to previous ones collected in the real control NPP room, indicating that the former may be executed before the later as a means of prototyping design and evaluation, before executing any real intervention
Humoral Immune Response Kinetics in Philander opossum and Didelphis marsupialis Infected and Immunized by Trypanosoma cruzi Employing an Immunofluorescence Antibody Test
Philander opossum and Didelphis marsupialis considered the most ancient mammals and an evolutionary success, maintain parasitism by Trypanosoma cruzi without developing any apparent disease or important tissue lesion. In order to elucidate this well-balanced interaction, we decided to compare the humoral immune response kinetics of the two didelphids naturally and experimentally infected with T. cruzi and immunized by different schedules of parasite antigens, employing an indirect fluorescence antibody test (IFAT). Both didelphids responded with high serological titers to different immunization routes, while the earliest response occurred with the intradermic route. Serological titers of naturally infected P. opossum showed a significant individual variation, while those of D. marsupialis remained stable during the entire follow-up period. The serological titers of the experimentally infected animals varied according to the inoculated strain. Our data suggest that (1) IFAT was sensitive for follow-up of P. opossum in natural and experimental T. cruzi infections; (2) both P. opossum and D. marsupialis are able to mount an efficient humoral immune response as compared to placental mammals; (3) experimentally infected P. opossum and D. marsupialis present distinct patterns of infection, depending on the subpopulation of T. cruzi, (4) the differences observed in the humoral immune responses between P. opossum and D. marsupialis, probably, reflect distinct strategies selected by these animals during their coevolution with T. cruzi