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161.
162.
Will synthetic biology elicit controversies similar to those of genetically modified crops before? Maybe, but where exactly are the analogies, and how can we gain substantial insights rather than mere guesses? We argue that as well as the intrinsic properties of the technologies at stake, the context of their implementation is decisive. To assess mechanisms of past and potential controversies, an investigative tool is presented. The Gate Resonance model, derived from older models of societal conflict, allows the identification of key elements of conflict generating processes. In monitoring the developing debate on synthetic biology using this model, analogies to the case of genetically modified crops appear less convincing. So far, there are only few indications that a controversy is imminent. 相似文献
163.
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
164.
张中菊 《Journal of Zhangzhou Technical Institute》2010,12(2):107-109
通过对高职院校学生未来职业特点进行分析,提出结合学生专业特点、职业场景、职业素养和职业保健四个方面来开展职业实用性体育.以期提高他们的职业适应能力,增强学生职业劳动的身体素质和心理承受能力. 相似文献
165.
Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively. 相似文献
166.
This paper demonstrates how the application of New Public Management (NPM) and the accompanying rise of academic capitalism
in allocating research funds in the German academic field have interacted with a change from federal pluralism to a more stratified
system of universities and departments. From this change, a tendency to build cartel-like structures of allocating symbolic
capital resulting in oligopolistic structures of appropriating research funds has emerged. This macro level structure is complemented
by the strengthening of the traditional oligarchic structures of research, carried out by an increasing number of assistants
under the direction of a professor on the meso level. The outcome of this institutional setting is a significant gap between
the appropriation of research funds according to the allocation of symbolic capital and the production of knowledge in publications.
The application of NPM therefore needs to be explained more as a result of the normative pressure of a globally established
model of “rational” administration, and less as a result of its functional effectiveness. This is demonstrated by an empirical
analysis with simple and multiple regressions using data on the allocation of research grants and publication records of German
chemistry departments. 相似文献
167.
In this study, passive samplers were used to measure ozone exposure distribution maps over the historical peninsula of Istanbul, Turkey. The study area is partially important due to the presence of cultural and historical buildings and structures distributed all over the peninsula. Unesco's World Heritage list covers four zones located in this historical peninsula in Istanbul. It is necessary to evaluate the pollution distribution in high resolution to construct effective risk management strategies. For this purpose, 50 sampling stations were installed within the study area. Three sampling campaigns within different seasons (summer, winter and fall) showing different ozone distribution characteristics were carried out. Seasonal measurements of ozone exposure values were used to obtain a yearly exposure level, which is an important part of risk characterization. Seasonal ozone exposure maps over the historical peninsula were obtained using Geographical Information Systems (GIS) based interpolation models with high resolution. Risk maps including five regions, based on ozone exposure levels were created. Structures and historical regions located within these risk zones were identified. Based on the defined exposure regions, we found that the Archaeological Park, one of the items on UNESCO's list, is located within the most risky region. 相似文献
168.
This study examines frequency, overlap, and genetic and environmental influences on sleep difficulties, which are understudied in school-aged children. The Sleep Self Report and the Children's Sleep Habits Questionnaire were completed by 300 twin pairs (aged 8 years) and their parents. Child report suggested more frequent sleep problems than parent report (e.g., regular sleep onset delay was reported by 45% of children and 17% of parents). Associations between most of the sleep difficulties were small but significant (e.g., r(s)=.16 for parent report of bedtime resistance and sleep onset delay). Twin correlations based on parent reports suggest greater genetic influence (M=50%) than those based on child self-report (M=18%). Possible rater effects should be considered when evaluating children's sleep problems. 相似文献
169.
Gül E. Okudan Susan Mohammed Madara Ogot 《European Journal of Engineering Education》2006,31(6):693-704
This paper presents the preliminary work for developing guidelines to ensure that industry-sponsored projects in first-year courses aid, not hamper, retention of students. Specifically, the overall research plan includes the following steps: (1) investigating the appropriateness of industry projects in a required introduction to engineering design course (approximately 1000 students per year), (2) assessing the impact of industry-sponsored projects on first-year students' learning and retention, and (3) promoting an awareness of issues involved in successfully introducing industry projects in the first year. It is expected that the outcomes of this work will result in guidelines widely applicable by other institutions looking into or currently using industry projects in the first year, thereby addressing the recognized national need of increasing retention rates, especially amongst women and minorities.
This paper covers a review of potential factors affecting industry-sponsored projects' appropriateness at the first year, and related preliminary data. 相似文献
170.
Who is the expert? Construct and criteria validity of student and teacher ratings of instruction 总被引:3,自引:1,他引:2
In this article, we examine the construct and criteria validity of student and teacher ratings as indicators of instructional
features. As parsimonious measures, student and teacher reports are frequently used to assess aspects of the learning environment.
From a methodological perspective, however, both approaches have been questioned. Whereas student ratings are occasionally
criticised as being undifferentiated and easily influenced by personal preferences, teacher reports are sometimes considered
to be biased by self-serving strategies or teaching ideals. Instead of pitting one method against the other, our study aimed
at establishing the specific value of each approach. The analyses draw on data from a German extension to the 2003 PISA assessment, in which 288 mathematics
teachers and their students completed questionnaires using identical items to tap various aspects of instruction. Mean student
ratings were computed for each class. Exploratory and confirmatory factor analyses revealed specific conceptual structures
for student and teacher ratings, with teachers elaborating on the use of tasks and methods, and students focusing on their
teacher’s support in personal and learning matters. Three shared dimensions were also established: occurrence of classroom
management problems, degree of cognitive autonomy during lessons, and tempo of interaction. Teacher/student agreement on these
dimensions varied across constructs, with considerable agreement on classroom management, low agreement on cognitive autonomy,
and no significant agreement on whether or not the interaction tempo was appropriate. Accordingly, correlations with external
criteria (student motivation, teacher motivation, mathematical achievement scores, and characteristics of the tasks set in
class) also varied across constructs. We conclude that student and teacher ratings are best suited to tapping different aspects
of the learning environment, and recommend that care be taken in choosing a data source appropriate for the construct to be
measured.
相似文献
Jürgen BaumertEmail: |