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981.
982.
At the University of Maine, middle and high school teachers observed more than 250 university science, technology, engineering, and mathematics classes and collected information on the nature of instruction, including how clickers were being used. Comparisons of classes taught with (n = 80) and without (n = 184) clickers show that, while instructional behaviors differ, the use of clickers alone does not significantly impact the time instructors spend lecturing. One possible explanation stems from the observation of three distinct modes of clicker use: peer discussion, in which students had the opportunity to talk with one another during clicker questions; individual thinking, in which no peer discussion was observed; and alternative collaboration, in which students had time for discussion, but it was not paired with clicker questions. Investigation of these modes revealed differences in the range of behaviors, the amount of time instructors lecture, and how challenging the clicker questions were to answer. Because instructors can vary their instructional style from one clicker question to the next, we also explored differences in how individual instructors incorporated peer discussion during clicker questions. These findings provide new insights into the range of clicker implementation at a campus-wide level and how such findings can be used to inform targeted professional development for faculty.  相似文献   
983.
The provision of the most comprehensive funded statewide delivery of diagnostic, protective and treatment services to abused and neglected children and their families in the country has been made possible by the State of Louisiana and its concerned citizenry. The importance of obtaining a legislative mandate establishing and funding the statewide child protection concept by the Louisiana legislature was illustrated.We described how the medical and protective services components cooperate and coordinate at the state and local levels to provide the abused and neglected child and his family with the best possible services available. Throughout our presentation the use of the interdisciplinary team concept was emphasized as the best system known to enhance the reporting, investigation and diagnosis of child abuse and/or neglect cases as well as providing protective and treatment services to the child and his family.The Child Protection Center is the community agency serving as the “core” for the interdisciplinary approach to be successful. The role of each discipline employed by the center was reviewed and how interagency coordination is accomplished through their efforts.The interdisciplinary dispositional conference prior to a child's discharge from the hospital was considered as an excellent method to insure that several disciplines share in the definitive protective and treatment plans for the abused child.Several treatment modalities and their success rates for the child and his family were discussed. The accomplishments of the center were listed.Finally, a review of how the citizenry from the Baton Rouge Community responded overwhelmly by their involvement and commitments in an all out effort to combat a serious social symptom and disease — child abuse and neglect.  相似文献   
984.
The present study examined the relationship of child maltreatment to both emotion dysregulation and subsequent eating pathology. In an effort to extend previous research, the authors examined the unique impact of childhood emotional abuse (CEA) on emotion dysregulation and eating disorder (ED) symptoms while controlling for the effects of sexual and physical abuse. Structural equation modeling was utilized to simultaneously examine the effects of all three abuse types on multiple dependent variables as well as examine whether deficits in emotion regulation mediated the relationship between abuse and eating pathology. Results from a survey of 1,254 female college students revealed significant paths from abuse subtypes to specific eating disorder symptoms, with CEA evidencing the strongest association with ED symptoms. Additionally, emotion dysregulation was positively associated with ED symptoms, and mediated the effects of emotional abuse on symptoms. Findings support previous research on the enduring effects of emotional abuse as well as highlight the importance of the assessment of CEA in the treatment of ED symptoms.  相似文献   
985.
986.
It has previously been shown that females incur less muscle damage than males after strenuous exercise, but limited data are available for humans. To determine possible differences between the sexes in humans, the response to high-force eccentric exercise was examined in a large sample of women (n = 83) and men (n = 82). The participants performed a bout of eccentric exercise of the elbow flexors consisting of 70 maximal repetitions. Isometric strength, resting elbow angle and muscle soreness were measured before, immediately after (except soreness) and then daily for 7 days after exercise. There was a significant loss in strength among both groups (69% for women and 63% for men) (P < 0.01) immediately after exercise; at 168 h post-exercise, women still had a 27% strength loss and men had a 24% strength loss. No significant difference in strength loss or recovery rate was found between men and women. Soreness reached peak values 32-48 h post-exercise (P < 0.01), with no significant difference between men and women. Range of motion decreased significantly until 3 days after exercise (14.6 degrees or 0.255 rad loss for women; 12.2 degrees or 0.213 rad loss for men) (P < 0.01); at 168 h post-exercise, the women and men still showed a loss of 4.8 degrees (0.084 rad) and 4.0 degrees (0.07 rad), respectively. There was a significant interaction of sex x time (P < 0.01); a post-hoc test indicated that the women experienced a greater loss in range of motion at 72 h than men and this difference was maintained to 168 h post-exercise (P < 0.01). Thus, our results do not support the contention that women have a lower response to eccentric exercise than men.  相似文献   
987.
Abstract

The purpose of this investigation was to compare the peak physiological responses among four protocols that employed different amounts of handweighted exercise in 16 males (aged 26.3 ± 4.1 years). The four protocols were (a) uphill treadmill running (UR; 3.36 m-s1, 2.5% grade increase-3 min1); (b) uphill treadmill walking while pumping 1.36kg handweights (HW) (UWHW; 1.79ms1, 5.0% grade increase-3 min1; (c) treadmill walking while pumping .91-kg HW (WHW; 1.79 m-s1, 0% grade, .91kg HW increase-3 min1); and (d) standing in place and pumping HW (SHW; arm work as described in WHW). It was hypothesized that the peak responses would be inversely proportional to the estimated muscle mass activated (i.e., UR = UWHW > WHW > SHW). Dependent variables included peak oxygen uptake (VO2 peak), peak heart rate (HRpeak), peak ventilation (Vepeak), and peak respiratory exchange ratio (RERpeak). No differences were noted between UR and UWHW with respect to any of the dependent variables. All variables (except RERpeak) were greater (p < .01) in UR and UWHW than either WHW or SHW. RERpeak was greater (p < .01) in UR and UWHW than in WHW. VO2peak and HRpeak were greater (p < .01) in WHW when compared to SHW. Mean VO2peak was 97.5, 69.7, and 60% of UR for UWHW, WHW, and SHW, respectively. Therefore, walking and pumping handweights provides a maximal stimulus to the oxygen transport system.  相似文献   
988.
Students were linked virtually across three contexts: U.S., Malaysia, and China. Differences emerged in how student-created messages were constructed and interpreted; these impacted perceived relational affiliation. Messages constructed by students in Malaysia and China exhibited casual talk, greater self-disclosure, requests for personal information, and greater use of emoticons/emoji. Interactions were perceived as informal, friendly, and positive. U.S. students’ messages often showed institutional talk, less self-disclosure, and more attention to the instructor-assigned task. Asian-U.S. student pairs perceived their interactions as formal, less friendly, and less positive. This study shows how online technologies may be afforded and shaped by culture and interaction.  相似文献   
989.
This paper presents a solution to the problem of global exact output tracking for uncertain MIMO (multiple-input–multiple-output) linear plants with non-uniform arbitrary relative degree using output feedback sliding mode control. The key idea to overcome the relative degree obstacle is to generalize our previous hybrid estimation scheme to a multivariable version by combining, through switching, a standard linear lead filter with a non-linear one based on robust exact differentiators, achieving uniform global exponential practical stability and exact tracking.  相似文献   
990.
The online public access catalog consists essentially of a machine-readable database with network capabilities. Like other computer-based information systems, it may be continuously enhanced by the addition of new capabilities and databases. It may also become a gateway to other information networks. This paper reports the evolution of the Bibliographic Access and Control System (BACS) of Washington University in end-user searching, current awareness services, information management, and administrative functions. Ongoing research and development and the future of the online catalog are also discussed.  相似文献   
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