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101.
Recently, European school systems have seen various attempts to ‘modernise’ their governance. Market and competition oriented reforms have not been central to governance innovation strategies in German speaking countries, however, their number and relevance is rising in recent years. A free school choice policy which abolishes “school districts” which legally define fixed school catchment areas was introduced in the school year of 2007/2008 in the Austrian city of Linz.The effects of the implementation of this policy on the primary school sector were studied by a standardised questionnaire administered to a representative sample of 3425 parents of five age groups of primary school children. The return rate was about 55%. By special measures during data collection a satisfactory representation of parents with migrant background was achieved.Three questions are discussed in the paper: (1) Is there a rise in segregation in schools as a result of free choice policy? (2) Is there a change in the composition of the student population in different schools as a result of free choice policy? (3) Is there a change in parent school choice behaviour of as a result of free choice policy?Our data indicates that segregation in primary schools with respect to ethnic and social family characteristics increases after the policy implementation, but the sample size is too small to find significant results. In addition, no significant change is observed in the social composition of schools. In accordance with the previous findings no significant modifications of choice behaviour occur for different ethnic or social groups after free choice. However changes in choice motives can be observed.  相似文献   
102.
Many innovation-oriented concepts have recently been discussed as means to improve science education and instruction as well as the corresponding tests and exit exams. So far, empirical evidence of whether these new concepts for exam tasks actually find their way into the exam practice is still pending. This contribution takes up this desideratum and exemplifically examines the tasks of statewide exit exams from selected countries in the subjects biology, chemistry and physics with regard to a possible increased context orientation in exam tasks as one prominent characteristic of the requested ‘innovative task culture’.  相似文献   
103.
This study investigated the longitudinal changes in the attitudes of pre‐service primary education teachers towards the teaching profession as they progressed through training. The results indicate that there is a significant difference in pre‐service teachers’ attitudes towards the profession between their freshman and senior years. Moreover, the findings obtained through interview data have shown that both positive and negative changes occur in pre‐service teachers’ attitudes towards teaching throughout their education, and these changes are observed to be related to teaching practice, cooperating teachers, teacher education institutions and teacher educators.  相似文献   
104.
This study aimed to compare teaching practice before and after 1998 in Turkey. Participants were 10 academics from the Department of Educational Sciences, Vocational Education Faculty, Gazi University and nine vocational high school cooperating teachers. Semi‐structured interviews were analysed by using content analysis. The most significant findings were that the preparation, practice, observation, counselling and evaluation processes were more efficient before 1998 due to the smaller number of preservice teachers. After 1998, the cooperating teachers were legally included in the process and took more responsibility. A new model which combines the positive aspects of both practices is suggested in the article.  相似文献   
105.
Quantifying the ubiquitous, ephemeral, and highly diverse patterns of mobile social media (MSM) use is a challenge for communication research. Most researchers employ retrospective survey measurement, thus depending on the accuracy of users’ memories and generalizations. Alternatively, some researchers rely on in-situ measurement, being less dependent on users’ memories and generalizations, but requiring random situation samples. To assess differences and similarities between these two measurement approaches we analyzed whether characteristics (duration and frequency of a usage episode, habit, elaboration, and gratifications) of MSM use (regarding Facebook, WhatsApp, and YouTube) vary between retrospective survey and mobile experience sampling measurement. We observe a consistent pattern of higher estimates in retrospect as compared to individual averages of in-situ reports. The absolute magnitude of these differences varies considerably between platforms and characteristics studied. Nonetheless, for most constructs and platforms we find low significant positive correlations between retrospective and aggregated in-situ values.  相似文献   
106.
The young field of neuroeconomics converges around behavioral deviations from the model of the human being as Homo economicus, a rational actor who calculates his choices to maximize his individual satisfaction. In a historical moment characterized by economic, health, and environmental crises, policymakers have become increasingly concerned about a particular deviation for which neuroeconomics offers a biological explanation: Why do humans value the present at the expense of the future? There is contentious debate within the field over how to model this tendency at the neural level. Should the brain be conceptualized as a unified decision-making apparatus, or as the site of conflict between an impetuous limbic system at perpetual odds with its deliberate and provident overseer in the prefrontal cortex? Scientific debates over choice-making in the brain, we argue, are also debates over how to define the constraints on human reason with which regulative strategies must contend. Drawing on ethnographic and archival research, we explore how the brain and its treatment of the future become the contested terrain for distinct visions of governmental intervention into problems of human choice-making.  相似文献   
107.
To prepare a biosynthetic module in an infochemical communication project, we designed a silicon/glass microreactor with anti-adsorption polyelectrolyte multilayer coating and immobilized alcohol acetyl transferase (atf), one of the key biosynthetic enzymes of the pheromone of Spodoptera littoralis, on agarose beads inside. The system reproduces the last step of the biosynthesis in which the precursor diene alcohol (Z,E)-9,11-tetradecadienol is transformed into the major component (Z,E)-9,11-tetradecadienyl acetate. The scope of this study was to analyze and implement a multilayer, anti-adsorption coating based on layer-by-layer deposition of polyethylenimine/dextransulfate sodium salt (PEI/DSS). The multilayers were composed of two PEI with molecular weights 750 and 1.2 kDa at pH 9.2 or 6.0. Growth, morphology, and stability of the layers were analyzed by ellipsometry and atomic force microscopy (AFM). The anti-adsorption functionality of the multilayer inside the microreactor was validated. The activity of His(6)-(atf) was measured by gas chromatography coupled to mass spectrometer (GC-MS).  相似文献   
108.
In this work a disposable, parallel microbioreactor (MBR) suitable for screening in batch or continuous mode is presented. The reactor consists of five parallel microchambers made of poly(dimethylsiloxane) bonded to a glass substrate. A grid structure is engraved on each chamber, allowing subsequent morphology imaging. Measurements are recorded over the entire cultivation period with constant parameters, namely, position and focus in the z-axis. The microdevice may be used for either parallel, uni- or multiparametric screening, and overcomes the drawback of gridless microwell plates which require expensive equipment such as an inverted microscope with an automatic stage. To validate the scalability from laboratory scale to microscale, and thus the cultivation protocol in the MBR, the germination of fungal spores (A. ochraceus) is evaluated for two different key magnitudes (pH and temperature) and compared to the results obtained from conventional laboratory scale systems (flasks and agar plates). Information on germination capacity with regard to interspecies' variability allows for optimization of industrial processes as optimal pH and temperature matched to the mesoscopic cultivation systems. The germination conditions therefore remain unaffected inside the MBR, while providing the following advantages: (i) dramatic reduction of medium consumption, (ii) submerged cultivation with constant oxygen supply, (iii) assured low cost and disposability, and (iv) possibility of a continuous cultivation mode.  相似文献   
109.
We examined differences in anthropometry and training between 64 Triple Iron ultra-triathletes competing over 11.4 km swimming, 540 km cycling, and 126.6 km running, and 71 Ironman triathletes competing over 3.8 km swimming, 180 km cycling, and 42.2 km running. The association of anthropometry and training with race time was investigated using multiple linear regression analysis. The Triple Iron ultra-triathletes were smaller (P < 0.05), had shorter limbs (P < 0.05), a higher body mass index (P < 0.05), and larger limb circumferences (P < 0.01) than the Ironman triathletes. The Triple Iron ultra-triathletes trained for more hours (P < 0.01) and covered more kilometres (P < 0.01), but speed in running during training was slower compared with the Ironman triathletes (P < 0.01). For Triple Iron ultra-triathletes, percent body fat (P = 0.022), training volume per week (P < 0.0001), and weekly kilometres in both cycling (P < 0.0001) and running (P < 0.0001) were related to race time. For Ironman triathletes, percent body fat (P < 0.0001), circumference of upper arm (P = 0.006), and speed in cycling training (P = 0.012) were associated with total race time. We conclude that both Triple Iron ultra-triathletes and Ironman triathletes appeared to profit from low body fat. Triple Iron ultra-triathletes relied more on training volume in cycling and running, whereas speed in cycling training was related to race time in Ironman triathletes.  相似文献   
110.

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