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981.
Paul B. Gastin Owen C. Mclean Ray V.P. Breed Michael Spittle 《Journal of sports sciences》2013,31(10):947-953
AbstractThe effectiveness of a wearable microsensor device (MinimaxXTM S4, Catapult Innovations, Melbourne, VIC, Australia) to automatically detect tackles and impact events in elite Australian football (AF) was assessed during four matches. Video observation was used as the criterion measure. A total of 352 tackles were observed, with 78% correctly detected as tackles by the manufacturer’s software. Tackles against (i.e. tackled by an opponent) were more accurately detected than tackles made (90% v 66%). Of the 77 tackles that were not detected at all, the majority (74%) were categorised as low-intensity. In contrast, a total of 1510 “tackle” events were detected, with only 18% of these verified as tackles. A further 57% were from contested ball situations involving player contact. The remaining 25% were in general play where no contact was evident; these were significantly lower in peak Player Load? than those involving player contact (P < 0.01). The tackle detection algorithm, developed primarily for rugby, was not suitable for tackle detection in AF. The underlying sensor data may have the potential to detect a range of events within contact sports such as AF, yet to do so is a complex task and requires sophisticated sport and event-specific algorithms. 相似文献
982.
Steven H. Chaffee Michael J. Petrick Bernard C. Hennessy John G. Cawelti 《Communication Booknotes Quarterly》2013,44(9):101-102
Steven H. Chaffee and Michael J. Petrick's Using the Mass Media: Communication Problems in American Society (New York: McGraw-Hill, 1975—$6.95, paper) Bibliography: Some Canadian Writings on the Mass Media (Ottawa: Canadian Radio-Television Commission , 1974—apparently free on request, paper) Communications: Some Federal Proposals (Ottawa: Information Canada, 1975—price not known, paper) Bernard C. Hennessy's Public Opinion (Belmont, Calif.: Duxbury Press/ Wadsworth, 1975—price not known, paper) John G. Cawelti's The Six-Gun Mystique (Bowling Green, Ohio: Bowling Green University Popular Press, 1972—price not known, paper) First Annual Report (Cambridge: Massachusetts Institute of Technology, December 1974—free on request, paper) 相似文献
983.
Many science educators encourage student experiences of “authentic” science by means of student participation in science‐related workplaces. Little research has been done, however, to investigate how “teaching” naturally occurs in such settings, where scientists or technicians normally do not have pedagogical training and generally do not have time (or value) receiving such training. This study examines how laboratory members without a pedagogical background or experience in teaching engage high school students during their internship activities. Drawing on conversation analysis, we analyze the minute‐by‐minute transactions that occurred while high school students participated in a leading environmental science laboratory. We find that the participation trajectory was based on demonstration‐practice‐connect (D‐P‐C) phases that continually recurred in the process of “doing” science. Concerning the transactional structures, we identify two basic conversation patterns—Initiate‐Clarify‐Reply (I‐C‐R) and Initiate‐Reply‐Clarify‐Reply (I‐R‐C‐R)—that do not only differ from the well‐known Initiate‐Reply‐Evaluate (I‐R‐E) patterns previously observed in science classrooms, but also could be combined to constitute more complex patterns. With respect to the organization of natural pedagogical conversations, we find that there were not only of preferred and dispreferred modes of responding but also ambiguous dispreferred modes; and the formulating organization not only includes self‐formulating but also other‐formulating. These natural pedagogical conversations helped, on the one hand, students to clarify their understanding and, on the other hand, technicians (or teachers) to teach toward different needs for different students in different contexts. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 46: 481–505, 2009 相似文献
984.
Theodore Michael Christou 《History of education》2013,42(5):566-577
This article examines educational rhetoric in Ontario, Canada, during the Great Depression. It notes how the government, through the Annual Reports of the Minister of Education, and the College of Education, through its journal, The School, espoused themes of social efficiency regarding educational ideas and policies. The Depression struck schools hardest between 1932 and 1935 in Ontario, providing cause and context for reflection and reform in pedagogy. While social efficiency remained within the educational discourse of the province, the notion was problematised in Ontario as the province began to shake off the worst of the economic Depression. 相似文献
985.
Jessica N. Byram Jason M. Organ Michael Yard Naomi A. Schmalz 《Anatomical sciences education》2020,13(2):149-157
The demand for upper-level undergraduate dissection-based anatomy courses is growing, as professional programs require more advanced anatomy training prior to matriculation. To address this need, Indiana University School of Medicine (IUSM) partnered with Indiana University-Purdue University Indianapolis—a large, urban, life science-focused campus nearby to IUSM—to offer an undergraduate, dissection-based course in regional gross anatomy. Because this is a new course, a deeper post-course evaluation of student perceptions was conducted using Q methodology. In this study, Q methodology was used to evaluate student views of the overall course structure, pre-laboratory materials and activities, assessments, and quality of instruction. Of the 15 students in the spring semester 2018 cohort, 80% (n = 12) participated in the evaluation, and 10 of those students followed up with written explanations for their rationale in selecting the four statements with which they most strongly agreed and disagreed. The Q methodology sorted the students into one of three statistically significant groups: Motivated Dissectors (n = 6), Traditional Students (n = 3), and Inspired Learners (n = 3). Motivated Dissectors and Inspired Learners felt strongly that the course did not encourage self-directed learning and that the pre-laboratory materials were not adequate to prepare them for quizzes. Traditional Students, however, disagreed, having a favorable opinion of the pre-laboratory materials, even though this group felt most strongly that the amount of material covered in the course was overwhelming. This study demonstrates the utility of Q methodology to evaluate courses to elucidate student perspectives and inform future course modifications. 相似文献
986.
Research Findings: Public policy has increasingly focused on expansion of preschool access for underserved students and systematic evaluation of preschool quality and students’ readiness for school. However, such evaluation is limited by a lack of thoroughly validated assessments for use with preschool populations. The present study examined the measurement and structural invariance of the Kindergarten Student Entrance Profile (KSEP) across kindergarten and prekindergarten groups to evaluate its potential use across developmental groups. Participants included 522 kindergarten and 548 prekindergarten students in central California. Invariance was tested by fitting a series of multiple-groups confirmatory factor analysis models with parameter constraints across groups. Results indicated that measurement and structural parameters of the KSEP were invariant across kindergarten and prekindergarten groups. Prekindergarten means on both Social–Emotional Readiness and Cognitive Readiness were significantly lower than kindergarten means. Practice or Policy: These results suggest that the KSEP may potentially be used with prekindergarten students to assess school readiness and inform intervention before kindergarten entry. 相似文献
987.
为研究海洋防污损涂料添加剂Irogarol-1051的降解产物M2的基因毒性,应用微阵列技术,选取Affymetrix公司鼠基因组230 2.0基因芯片检测30μmol/L M2暴露下的鼠肝癌细胞基因表达变化.实验结果显示,96 h的M2暴露导致了38个基因在全部4组可能的对照/暴露中均发生显著变化(p0.002 5),其中只有Accn5基因研究较为透彻,该基因表达的抑制可能影响上皮钠通道的功能.此外,分别有10和82个功能注释基因在至少一组对照/暴露组中上调和下调.M2诱导的基因主要和细胞核(细胞成分)相关.M2抑制的基因则主要影响生物过程中的G蛋白偶联信号通路功能和细胞成分中的细胞膜内整合功能. 相似文献
988.
Carrie B. Myers Doreen E. Brown D. Michael Pavel 《Journal of Education for Students Placed at Risk》2013,18(4):299-321
The purpose of this study was to assess how a comprehensive precollege intervention and developmental program among low-income high school students contributed to college enrollment outcomes measured in 2006. Our focus was on the Fifth Cohort of the Washington State Achievers (WSA) Program, which provides financial, academic, and college preparation support to 500 high school students who come from the lowest 35% of Washington state income levels. One important feature of the WSA Program is that it provided funding for complete high school curriculum reform among 16 Washington high schools that have a high prevalence of low-income students. The data set contained three groups of students from these 16 high schools: Funded Achievers who were part of the WSA Program and received funding for college; Nonfunded Achievers who were part of the WSA Program and but did not receive funding for college; and Nonrecipients who were neither part of the WSA Program nor received funding for college. Results from generalized multinomial logistic models found two trends (a) early and continuous financial support for college along with being active in the WSA Program nearly guarantees enrollment in college and increases enrollment in 4-year and highly selective colleges; and (b) even in the absence of financial support for college there are still quantifiable and positive effects on college-going for just participating in the WSA Program and receiving its abundant nonfinancial resources and support. These results persist even with strong controls for selection, background, academic, financial, aspiration, and school-level variables. 相似文献
989.
This paper presents the optimal filtering and parameter identification problem for linear stochastic systems over linear observations with unknown parameters, where the unknown parameters are considered Wiener processes. The original problem is reduced to the filtering problem for an extended state vector that incorporates parameters as additional states. The resulting filtering system is bilinear in state and linear in observations. The obtained optimal filter for the extended state vector also serves as the optimal identifier for the unknown parameters. Performance of the designed optimal state filter and parameter identifier is verified for both, positive and negative, parameter values. 相似文献
990.