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101.
对史学界关于汪精卫叛国投敌的决定性因素的七种争议进行综述 ,并提出几点思考  相似文献   
102.
In this paper we discuss a novel storage scheme for simultaneous memory access in parallel turbo decoder. The new scheme employs vertex coloring in graph theory. Compared to a similar method that also uses unnatural order in storage, our scheme requires 25 more memory blocks but allows a simpler configuration for variable sizes of code lengths that can be implemented on-chip. Experiment shows that for a moderate to high decoding throughput (40-100 Mbps), the hardware cost is still affordable for 3GPP's (3rd generation partnership project) interleaver.  相似文献   
103.
The purpose of this study was to assess the validity of accelerometers using force plates (i.e., ground reaction force (GRF)) during the performance of different tasks of daily physical activity in children. Thirteen children (10.1 (range 5.4–15.7) years, 3 girls) wore two accelerometers (ActiGraph GT3X+ (ACT), GENEA (GEN)) at the hip that provide raw acceleration signals at 100 Hz. Participants completed different tasks (walking, jogging, running, landings from boxes of different height, rope skipping, dancing) on a force plate. GRF was collected for one step per trial (10 trials) for ambulatory movements and for all landings (10 trials), rope skips and dance procedures. Accelerometer outputs as peak loading (g) per activity were averaged. ANOVA, correlation analyses and Bland–Altman plots were computed to determine validity of accelerometers using GRF. There was a main effect of task with increasing acceleration values in tasks with increasing locomotion speed and landing height (P < 0.001). Data from ACT and GEN correlated with GRF (r = 0.90 and 0.89, respectively) and between each other (r = 0.98), but both accelerometers consistently overestimated GRF. The new generation of accelerometer models that allow raw signal detection are reasonably accurate to measure impact loading of bone in children, although they systematically overestimate GRF.  相似文献   
104.
Background:Physical activity(PA)has substantial health benefits and is important in combatting chronic diseases,which have been associated with elevated levels of advanced glycation endproducts(AGEs).AGEs play a role in the aging process,and an association between PA and AGEs has been reported.We aimed to investigate the relationship between PA and AGE accumulation in a general population and in a population with chronic diseases.Methods:This large cross-sectional population study used data from adult participants in the LifeLines project,with participant information drawn from the LifeLines database as well data from patients with diabetes mellitus or renal and/or cardiovascular diseases.Tissue AGE accumulation was assessed non-invasively by skin-autofluorescence(SAF)using an AGE reader(DiagnOptics Technologies BV,Groningen,the Netherlands).PA was assessed using the short questionnaire to assess health-enhancing physical activity(SQUASH).Multivariate linear regression analyses were adjusted for age,body mass index,sex,and smoking status.Results:Data from 63,452 participants(general population n=59,177,chronic disease n=4275)were analyzed.The general population was significantly younger(43.58±11.77 years,mean±SD)and had significantly lower SAF(1.90±0.42 arbitrary units(AU))compared to the population with chronic disease(age:55.51±12.07 years;SAF:2.27±0.51 AU).In the group with chronic disease,more hours of moderate to vigorous physical activities per week were associated with lower SAF(β=-0.002,95%confidence interval(95%CI):-0.002 to-0.001).For the general population,there was no association between hours of moderate to vigorous activity and SAF(β=3.2×10-5,95%CI:0.000-0.001,p=0.742).However,there was an association in the general population between total hours of PA per week and SAF(β=4.2×10-4,95%CI:0.000-0.001,p<0.001),but this association was not found in the chronic disease population(β=-3.2×10-4,95%CI:-0.001 to 0.000,p=0.347).Conclusion:Our study demonstrates that an inverse relationship exists between PA and AGE accumulation in the population with chronic disease.More hours of moderate to vigorous activity is associated a significantly decreased SAF.More PA is associated a lower SAF,even after for the established predictors(age,body mass index,smoking status,and sex).Our findings could help to promote health and prolong longevity.  相似文献   
105.
Initial intervention processes for children with intellectual disabilities (IDs) largely focused on direct efforts to impact core cognitive and academic deficits associated with the diagnosis. Recent research on risk processes in families of children with ID, however, has influenced new developmental system approaches to early intervention. Recent risk and resilience processes are reviewed that connect stress, family process, and the high rates of behavioral problems in children with ID that have substantial influence on child and family outcomes. These models are linked to emerging evidence‐based intervention processes that focus on strategic parent skill training and mindfulness interventions that reduce parental stress and create indirect benefits for children's behavioral competencies. A family‐focused developmental systems approach (M. J. Guralnick, 2011) is emphasized.  相似文献   
106.
The roles and responsibilities of university supervisors in the practicum have changed during the last ten years. Once, the routine tasks of observation and feedback of student teaching performance were the main responsibilities associated with visits to the school. Lecturers in this role also determined, with the school personnel, the assessment rating of the student teacher. Presently, there is considerable variation in the part played by university supervisors of the practicum. Against this background, this paper examines the actual and ideal characteristics of university supervisors from their own viewpoint and from the perspective of teacher supervisors, principals and student teachers. The reasons for the actual‐ideal discrepancies are discussed, and suggestions are made in relation to addressing the matter.  相似文献   
107.
学校教育教学的主要途径是课堂教学,提高课堂教学效率的较好方法是有效选用教学案例。文章从教学案例的材料来源上,强调教学案例选用客观性;联系教学内容,讨论教学案例选用的适用性;依据学生的实际,阐述教学案例选用的针对性;依据教学过程,介绍教学案例有效的选用方法,提高教学案例在课堂教学中的有效性,从而达到提高课堂教学的效率。  相似文献   
108.
A growing number of studies examine the influence of individual factors on acculturation attitudes of immigrants, but few studies focus on majority members’ attitudes. In this paper, two studies are reported on the relation between attachment styles and acculturation attitudes of both immigrants (N=177) and majority members (N=243) in the Netherlands. Until now very few studies have associated cultural adjustment with attachment styles. This is remarkable, because attachment theory refers to interaction with others in new situations. Four different styles of attachment (the secure, dismissing, preoccupied and fearful attachment styles) are related to Berry's classification of acculturation attitudes. People, both immigrants and majority members, with a secure attachment style were positive towards integration, whereas people with a dismissing attachment style were not. Dismissing immigrants were more positive towards separation. Whereas both immigrants and majority members with a secure attachment style showed a similar pattern of correlations between attachment and acculturation, they seem to react quite differently, and even in opposite ways, when they have a preoccupied attachment style. Yet, the different reactions may be caused by the same psychological process: The existential ambivalence of preoccupied people may lead to diverse reactions.  相似文献   
109.
实践性教学是实现高等学校教学目标、培养和造就具有创新精神和实践能力的高素质人才的重要环节。笔者结合多年普通植物病理学实践性教学的经验,从改进实验课教学、加强教学实习环节、改革传统考核制度、鼓励学生走进实验室、在教师的指导下参与科研活动、提高任课教师的综合素质等多方面探讨了普通植物病理学具体的实践性教学方法,并提出了该学科实践性教学中有待改进和加强的方面。  相似文献   
110.
在用户操作现场感知用户需求,采用情景驱动,将科技文献服务即时嵌入到用户的工作流程之中。介绍了这种嵌入式桌面信息服务的基本思想及系统设计、实现方法。  相似文献   
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