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221.
I. Rothman 《科学教学研究杂志》1967,5(2):168-173
Scores on a science-related semantic differential test are small but significant predictors of physics and chemistry achievement. 相似文献
222.
223.
R H Orr V M Pings E E Olson I H Pizer 《Bulletin of the Medical Library Association》1968,56(4):380-403
A standardized procedure was developed for eliciting those details of a library's service policies that are important to its users and for recording the data by checking appropriate categories on a form. This inventory procedure covers the entire spectrum of user services and accommodates a wide range of policies. The inventory was originally designed for use by trained interviewers in largescale surveys of academic medical libraries. However, it is also suitable for other kinds of libraries, and the Interview Guide and Checklist can be used for a self-survey by library staff. In addition to survey use, the inventory has a variety of educational, administrative, managerial, and research applications. A method for weighting the categorical inventory data to reflect the relative desirability of different policies makes it possible to calculate scores indicating how a library's policies compare with those of an "optimal" library. An analogous inventory of the services a library provides to other libraries was developed for surveying major backup resources in the medical library system. 相似文献
224.
In this paper, the asymptotic behavior of a generalized Solow model with endogenous labor growth and impulsive perturbations at fixed moments of time is studied. By using the Lyapunov–Razumikhin method sufficient conditions for week uniform asymptotic stability of the solutions are obtained. We also show that the role of impulses in control the behavior of solutions of impulsive models is very important. 相似文献
225.
Schmitt KU Wider D Michel FI Brügger O Gerber H Denoth J 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):57-72
Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s. 相似文献
226.
Habib M Hussain I Fang WH Rajput ZI Yang ZZ Irshad H 《Journal of Zhejiang University. Science. B》2006,7(4):320-323
In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time in- tervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37℃, whereas formalin at 0. 1% and 0.2% concentrations inactivated IBDV in 24 h. 相似文献
227.
Johnson RJ Ross MW Taylor WC Williams ML Carvajal RI Peters RJ 《Child abuse & neglect》2006,30(1):75-86
OBJECTIVE: The current study examined the prevalence and characteristics of childhood sexual abuse in a jailed-based population. METHODOLOGY: A retrospective, self-reported survey was administered over an 8-week period to a random sample of 100 men who were incarcerated in a county jail in Southeastern Texas. The survey included questions about childhood sexual experiences before and after puberty, drug history and use, and sexual risk-taking behaviors. RESULTS: Of the 100 male inmates who participated in this study, 59% reported experiencing some form of sexual abuse before puberty, and all such instances occurred before or at the age of 13 years. The first episode of childhood sexual abuse began at an average age of 9.6 years (SD = 2.4), and ended at an average age of 13.0 years (SD = 2.3). Kissing and touching without intercourse (64%) was the common pattern of sexual abuse experience reported. The total number of perpetrators was 165, with 10% male and 90% female. Friends (n = 72) and family (n = 56) were the most frequent perpetrators. CONCLUSION: Childhood sexual abuse may be more prevalent among inmates than among males in the general population. These results show a high percentage of inmates who report a history of childhood sexual abuse; this rate is higher than those reported by other studies for incarcerated males. The findings support the belief held by professionals in the criminal justice field that a significant number of incarcerated males may have been victims of sexual abuse. 相似文献
228.
This is a brief information and analytical survey of the papers submitted to the Second International Nanotechnology Forum
held in Moscow in October 2009. Scientometric data on the participants, their origins by regions and research centers, as
well as an analysis of the advancements and problems of Russian research in nanotechnologies, are given. 相似文献
229.
230.
J. M. Hills G. Robertson R. Walker M. A. Adey I. Nixon 《Teaching in Higher Education》2013,18(2):211-231
This article investigates the gap between employers' requirements of graduates and the skills which graduates are furnished with through degree programmes in the higher education (HE) sector in the UK. A survey of 88 subject review reports prepared by the Quality Assurance Agency (QAA) for environmentally related units in the UK showed little emphasis on employability issues. Surveys of first destination statistics of a cohort of graduates from two biological degrees and from national data showed that a significant proportion of graduates were in non-science-based activities. The non-knowledge-based learning outcomes from one degree were investigated, and showed that employability aspects were partially covered in the programme, but were not always associated with secure assessments. The concept of work-related learning is defined and a conceptual framework for HE practitioners is presented that could be used when designing curricula to better map programme learning outcomes onto graduate employment. 相似文献