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51.
The present study investigated the hypothesis that the higher prevalence of reading disability (RD) often observed among boys is partly an artifact of gender bias in the prediction of reading from IQ. The relevant regression statistics derived from a sample of more than 900 children revealed a statistically significant intercept bias. Predicted reading scores for boys were systematically overestimated, thereby inflating IQ-reading discrepancies; the converse was found for girls. When defined separately for girls and boys, severe underachievement in reading was found to be equally prevalent in both genders and, furthermore, was associated with qualitatively and quantitatively similar patterns of deficits. Because the bias arose from general differences between boys and girls in reading score distributions (a lower mean and greater variance for boys) rather than from differences in IQ scores, gender bias poses a potential threat not only to traditional IQ-discrepancy definitions but also to post-discrepancy definitions that are based solely on reading score cutoffs. Future classification criteria for RD need to take heed of the possibility that when the distributions of reading scores for boys and girls are not identical, performance cutoffs designating low achievement that are based on data pooled from both genders are likely to result in the overidentification of boys with RD and the underidentification of girls with RD.  相似文献   
52.
This paper examines social coordination by the Brazilian Black Movement in the area of Brazilian education. It explains how these developments relate to the construction of race-based public education policies in the country. Focus goes to the process of creation and implementation of law 10.639 in Brazilian Basic education. Using the concept ‘diffuse governance’, the argument is made that at present it are the multiple actions by the Brazilian Black Movement, in diverse arenas of dispute, and interacting with a range of actors, that enable us to understand the social coordination/regulation in the process of constructing and implementing Law 10.639.  相似文献   
53.
In the presence and absence of an externalinterfood clock stimulus (a sequence of flashing lights), rats showed a multimodal behavior pattern during successive quarters of interfood intervals (IFI) ranging from 12 to 192 sec. Responses near the feeder peaked before and just after food presentations, whereas locomotion remote from the feeder peaked toward the middle of the IFI. The temporal patterns of nosing in the feeder and remote locomotion were scalar (the time at which a response peaked in the IFI was proportional to the IFI length), whereas the patterns of postfood feeder-directed behavior, rearing, and pawgrooming were time bound (peaking at a fixed time after food, regardless of IFI length). Responses varied in their control by the external clock stimulus. During the last half of the IFI, rats nosed in the feeder more with an external clock, but only at intermediate IFIs. During the first quarter of the IFI, rats pawgroomed more with an external clock, but only at the longest IFI. The general sequence of responses during the interfood clock was consistent with the view that food delivery engages an organized sequence of search states that are expressed through a variety of responses.  相似文献   
54.
A family developmental framework was applied to data from families of children with intellectual disabilities to understand the role of parenting in the path from early adversity to problem behaviors in mid-childhood. Data from 9 months to 11 years tested the Family Stress Model in families of 555 children. Adversarial parenting between 3 and 5 years mediated the path from early adversity (family poverty and maternal psychological distress at nine months) to problem behaviors at 7 and 11 years. Positive parent–child relationship only mediated the path to conduct problems. Multiple mediation was not present. Early adversity impacts both positive parent–child relationship and adversarial parenting between three and five, but the latter is crucial for problem behaviors in mid-childhood.  相似文献   
55.
Cooperation in innovation activities: The importance of partners   总被引:1,自引:0,他引:1  
This paper analyses the importance of cooperation partners for the development of innovation activities. We contribute to the literature on cooperation in innovation activities that seeks to identify the characteristics differentiating cooperative from non-cooperative firms by proposing a different approach to this problem. We distinguish firms according to their evaluation of cooperation partners in the development of innovation activities. We apply a probit selection model to account for the firm's decision to cooperate (or not). The data we use come from the Portuguese Third Community Innovation Survey. Our estimation results show that firms from high-technological industries, with higher levels of absorptive capacity and of innovation investment, who give importance to incoming spillovers management, and who cooperate with firms from the same group or with suppliers, place greater value on cooperation partners in the innovation process. Additionally, we also find that the factors influencing the importance attributed to cooperation activities are different from the ones behind the decision to cooperate.  相似文献   
56.
Queries submitted to search engines can be classified according to the user goals into three distinct categories: navigational, informational, and transactional. Such classification may be useful, for instance, as additional information for advertisement selection algorithms and for search engine ranking functions, among other possible applications. This paper presents a study about the impact of using several features extracted from the document collection and query logs on the task of automatically identifying the users’ goals behind their queries. We propose the use of new features not previously reported in literature and study their impact on the quality of the query classification task. Further, we study the impact of each feature on different web collections, showing that the choice of the best set of features may change according to the target collection.  相似文献   
57.
Two experiments evaluated history effects on induced and operant variability. College students typed three-digit sequences on a computer keyboard. Sequence variability was induced (by no reinforcement or variation- independent reinforcement) or reinforced (by variation- or repetition-dependent reinforcement). Conditions with induced and operant variability were presented according to a reverse between-groups design. In Experiment 1, we examined transitions from the variation or repetition contingencies to no reinforcement, and vice versa. In Experiment 2, the variation or repetition contingencies were followed or preceded by variation-independent reinforcement. The results showed that (1) a history of no reinforcement impaired operant variability learning; (2) induced variability levels were higher and lower after a history of reinforcement for variation and repetition, respectively; (3) repetition was more easily disrupted by no reinforcement and independent reinforcement than was variation; and (4) response variability and stability were a function of past and current reinforcement conditions. These results indicate that reinforcement history influences both induced and operant variability levels.  相似文献   
58.
The aim of this study was to analyze the effects of resistance training (RT) performed with 1 or 3 sets per exercise on osteosarcopenic obesity (OSO) syndrome parameters in older women. Sixty-two older women (68.0 ± 4.3 years, 26.8 ± 4.4 kg/m2) participated in a 12-week RT program. Participants were randomly assigned into one of the three groups: two training groups that performed either 1 set (G1S, n = 21) or 3 sets (G3S, n = 20) 3 times weekly, or a control group (CG, n = 21). Body composition was assessed by dual X-ray absorptiometry, strength was evaluated by 1 repetition maximum testing. The G3S presented significantly higher strength changes than G1S. The changes for percentage of body fat were higher for G3S compared to G1S. There was no difference in skeletal muscle mass between G3S and G1S, however both training groups displayed greater increases in this outcome compared to CG. There was no effect for bone mineral density. The overall analysis indicated higher (< 0.05) positive changes for G3S than G1S (composed Z-score: G3S = 0.62 ± 0.40; G1S = 0.11 ± 0.48). The results suggest that a 12-week RT period is effective to improve the risk factors of OSO, and that 3 sets induce higher improvements than a single set.  相似文献   
59.
We investigated whether low-level laser therapy (LLLT) prior to or post resistance exercise could attenuate muscle damage and inflammation. Female Wistar rats were assigned to non-LLLT or LLLT groups. An 830-nm DMC Laser Photon III was used to irradiate their hind legs with 2J, 4J, and 8J doses. Irradiations were performed prior to or post (4J) resistance exercise bouts. Resistance exercise consisted of four maximum load climbs. The load work during a resistance exercise bout was similar between Control (non-LLLT, 225 ± 10 g), 2J (215 ± 8 g), 4J (210 ± 9 g), and 8J (226 ± 9 g) groups. Prior LLLT did not induce climbing performance improvement, but exposure to 4J irradiation resulted in lower blood lactate levels post-exercise. The 4J dose decreased creatine kinase and lactic dehydrogenase levels post-exercise regardless of the time of application. Moreover, 4-J irradiation exposure significantly attenuated tumor necrosis factor alpha, interleukin-6, interleukin-1β, cytokine-induced neutrophil chemoattractant-1, and monocyte chemoattractant protein-1. There was minor macrophage muscle infiltration in 4J-exposed rats. These data indicate that LLLT prior to or post resistance exercise can reduce muscle damage and inflammation, resulting in muscle recovery improvement. We attempted to determine an ideal LLLT dose for suitable results, wherein 4J irradiation exposure showed a significant protective role.  相似文献   
60.
The present study examined whether gender, ethnicity, instructional medium and school category differences manifest in science performance and motivation to learn science among secondary school students in Sri Lanka. The mean of five successive term test scores was used as the measure of science performance. Level of motivation in terms of six dimensions was measured by using the Science Motivation Questionnaire. A sample of 1316 grade 11 students representing Sinhala, Tamil, and Muslim ethnic groups from the three categories of public schools, which provide instructions in the vernacular languages of Sinhala or Tamil, participated in the study. Girls showed significantly higher performance in science compared to boys, and there was a significant gender difference in the levels of motivational dimensions in favor of girls. Although Tamil medium students possessed a higher level of motivation to learn science, Sinhala medium students outperformed their Tamil medium counterparts in science performance. Significant differences in science performance between Sinhala, Tamil, and Muslim students were also observed. However, motivation towards learning science between Tamils and Muslims was not significantly different. Highly significant differences in both motivation to learn science and performance in science were found between three categories of schools. The present study provides information to education officials who have to achieve equity across gender, ethnicity, medium of instruction, and school category, teachers who deliver the subject and school principals who design academic support programs.  相似文献   
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