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71.
This paper presents a relevance model to rank the facts of a data warehouse that are described in a set of documents retrieved with an information retrieval (IR) query. The model is based in language modeling and relevance modeling techniques. We estimate the relevance of the facts by the probability of finding their dimensions values and the query keywords in the documents that are relevant to the query. The model is the core of the so-called contextualized warehouse, which is a new kind of decision support system that combines structured data sources and document collections. The paper evaluates the relevance model with the Wall Street Journal (WSJ) TREC test subcollection and a self-constructed fact database.  相似文献   
72.
The purpose of this study was to investigate the tracking of gross motor coordination (GMC) and to profile children at 6 years of age who consistently showed higher stability patterns in different levels of GMC. The participants were 245 children (123 boys and 122 girls) who were assessed longitudinally from 6 to 9 years of age. GMC was assessed using the Korperkoordinationtest fur Kinder (KTK) test battery. Anthropometry, physical activity, and health- and performance-related physical fitness were also measured. Cohen’s kappa (κ) was used to estimate tracking. Tracking was poor for all GMC tests (0.17 ≤ κ ≤ 0.38) and moderate for the GMC motor quotient (MQ) in both boys and girls (0.44 ≤ κ ≤ 0.45). Instability at the extremes was low in GMC tests and negligible for MQ. Children who consistently showed high GMC levels during the 4 years of follow-up were lighter, had lower body mass index and subcutaneous fat, and showed higher scores in physical fitness tests at 6 years of age than those who consistently had low GMC levels. In conclusion, GMC showed low-to-moderate tracking over time in childhood. However, children who consistently demonstrated high GMC levels over time had healthier profiles at 6 years of age.  相似文献   
73.
This study evaluated the effect of a multi-component intervention on motor performance (MP) and metabolic risk markers (MRM) in overweight/obese youth. A secondary aim was to examine whether changes in MP are associated to changes in MRM. A 3-month multi-component intervention was performed, consisting of physical exercise sessions (twice/week;1h), nutritional education sessions (once/month), and parental support (twice/week). The sample included 35 volunteers (7–13 y.o), allocated to intervention (INT, n = 17) and control (CONT, n = 18) group. Variables were measured pre (T0) and post intervention (T1). Fasting blood samples were analyzed for MRM. MP tests included the measurement of health related physical fitness components and motor coordination performance (KTK battery). To assess food intake, a 24-hour recall diary was used. GLM-ANCOVA was performed. Standardized scores were calculated for the outcome variables, and multilinear regressions were applied to analyze associations between the key variables. INT group showed improvements in MP, glycolytic and hepatic profiles. After adjustments for MVPA, SB, total intake and maturational stage, negative associations between %ΔMP and %Δglycolytic (β = -.424; 95%CI:-0.343:-0.022), and %Δhepatic scores (β = -.382 95%CI:-0.001:-0.009) were observed. The intervention produced a moderate-to-high effect on the MP and some MRM. Changes in MP were inversely associated with changes in glycolytic and hepatic markers.  相似文献   
74.
Wild botanic gardens consist of natural or semi-natural land remnants immersed in large urban areas or botanic gardens, which are managed for purposes of biodiversity preservation and public recreation. In Latin America, they tend to be affected by budget limitations; however, they serve as valuable resources that permit the development of innovative environmental education programmes. Specifically, we are considering the appropriateness of implementing critical environmental education and socio-constructivist programmes. As for practical considerations, it is important to include diverse epistemologies, and therefore, strategies or procedures characteristic of science teaching, such as problem-based learning, together with other characteristics of social activism and popular education initiatives, such as assemblies or meetings, and others characteristic of more traditional and indigenous worldviews, such as celebrations of the earth. In this way, Latin American wild botanic gardens may play a role in constructing environmentally responsible societies and the nurturing of a culture of reflective inquiry.  相似文献   
75.
The objective of the present study was to investigate the effects of different sports on stress fractures among adolescents during a 9-month follow-up period. The sample was composed of 184 adolescents divided into three groups (impact sports [n = 102]; swimming [n = 35]; non-sports [n = 47]). The occurrence of stress fracture was reported by participants and coaches. As potential confounders we considered age, sex, resistance training, body composition variables and age at peak of height velocity. There were 13 adolescents who reported fractures during the 9-month period. Bone mineral density values were higher in adolescents engaged in impact sports (P-value = 0.002). Independently of confounders, the risk of stress fracture was lower in adolescents engaged in impact sports than in non-active adolescents (hazard ratio [HR] = 0.23 [95% confidence interval (CI) = 0.05 to 0.98]), while swimming practice was not associated to lower risk of fracture (HR = 0.49 [95% CI = 0.09 to 2.55]). In conclusion, the findings from this study indicate the importance of sports participation among adolescents in the reduction of stress fracture risk, especially with impact sports. More importantly, these results could be relevant for recognising adolescents in danger of not reaching their potential for peak bone mass and later an increased risk of fractures.  相似文献   
76.
The aim of this study was to propose a new force parameter, associated with swimmers’ technique and performance. Twelve swimmers performed five repetitions of 25 m sprint crawl and a tethered swimming test with maximal effort. The parameters calculated were: the mean swimming velocity for crawl sprint, the mean propulsive force of the tethered swimming test as well as an oscillation parameter calculated from force fluctuation. The oscillation parameter evaluates the force variation around the mean force during the tethered test as a measure of swimming technique. Two parameters showed significant correlations with swimming velocity: the mean force during the tethered swimming (r = 0.85) and the product of the mean force square root and the oscillation (r = 0.86). However, the intercept coefficient was significantly different from zero only for the mean force, suggesting that although the correlation coefficient of the parameters was similar, part of the mean velocity magnitude that was not associated with the mean force was associated with the product of the mean force square root and the oscillation. Thus, force fluctuation during tethered swimming can be used as a quantitative index of swimmers’ technique.  相似文献   
77.
Two-dimensional (2D) rare-earth oxides (REOs) are a large family of materials with various intriguing applications and precise facet control is essential for investigating new properties in the 2D limit. However, a bottleneck remains with regard to obtaining their 2D single crystals with specific facets because of the intrinsic non-layered structure and disparate thermodynamic stability of different facets. Herein, for the first time, we achieve the synthesis of a wide variety of high-quality 2D REO single crystals with tailorable facets via designing a hard-soft-acid-base couple for controlling the 2D nucleation of the predetermined facets and adjusting the growth mode and direction of crystals. Also, the facet-related magnetic properties of 2D REO single crystals were revealed. Our approach provides a foundation for further exploring other facet-dependent properties and various applications of 2D REO, as well as inspiration for the precise growth of other non-layered 2D materials.  相似文献   
78.
In this longitudinal study, the cross-language transfer from second language (L2) to first language (L1) was examined among Spanish-speaking English-language learners in an English intervention (Grades 1–3) in the southwest United States. Path analysis revealed statistically significant transfers (ps < .05) for the treatment group from English reading comprehension to Spanish reading comprehension. English vocabulary and English grammar also had an indirect influence on Spanish reading comprehension through English reading comprehension. For the comparison group, no English to Spanish paths were statistically significant. We concluded that intervention activities in L2 influenced L1 reading even when L1 instructional time was reduced.  相似文献   
79.
The authors of this quantitative study measured and compared the academic language development and conceptual understanding of fifth-grade economically disadvantaged English language learners (ELL), former ELLs, and native English-speaking (ES) students as reflected in their science notebook scores. Using an instrument they developed, the authors quantified the student notebook language and concept scores. They compared language growth over time across three time points: beginning, middle, and end of the school year and across language-status (ELL, former ELL, and ES), and gender using mixed between-within subjects analysis of variance (ANOVA). The authors also compared students’ conceptual understanding scores across categories in three domains using ANOVA. Students demonstrated statistically significant growth over time in their academic language as reflected by science notebook scores, and we noticed conceptual trends in which scores for ELLs, former ELLs, and male students lagged behind at first, but caught up to their peers by the end of the school year.  相似文献   
80.
Cognitive event-related potentials (ERPs) were recorded from 23 maltreated and 21 nonmaltreated children. Children were presented with slides of Ekman photographs of asingle model posing an angry (25%), a happy (25%), or a neutral (50%) facial expression. In 1 of 2 counterbalanced target conditions, children were asked to press a button in response to the angry face; in the other target condition, they responded to the happy face. Both samples, as expected, exhibited the largest amplitude of the P300 component of the ERP to target stimuli and the smallest amplitude to nontargets. For nonmaltreated children, the average amplitude of P300 across slides was comparable for the 2 target conditions. In contrast, maltreated children displaed larger P300 ampltude to stimuli when they were directed to attend to angry, as opposd children displayed larger p300 amplitude to stimuli whe they were directed to attend to angry, as opposed to happy, targets. These reaults suggest different cognitive processing for positive versus negative affective expressions by children with histories of atypical emotiaonal exotional experiences.  相似文献   
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