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961.
Dr. habil. Kai Maaz Univ.-Prof. Dr. Ulrich Trautwein Dipl.-Soz. Wiss. Cornelia Gresch Univ.-Prof. Dr. Oliver Lüdtke Univ.-Prof. Dr. Rainer Watermann 《Zeitschrift für Erziehungswissenschaft》2009,12(2):281-301
Indicators of social background belong to the standard set of instruments for empirical research in education. Construction of valid ranking scales and category systems for social background depends on a differentiated surveying of the occupation and vocational activity of parents. Coding such details using standard procedures is a complex process. This contribution investigates the intercoder-reliability of occupational codes according to ISCO-88 and the indicators for socio-economic status (ISEI) based on these codes using a random sample of 300 graduates surveyed on the occupation of their father and mother. To this aim, we compared a double-coding by professional coders and a double-coding by the research team. The results show a match of around 50 percent between the two coding groups. The validity of the index of socio-economic status based on the data was, however, very good. The correlation between ISEI-values based on the coding from the different coders was very high. The predication of family background did not vary between the coding of the different coding groups. 相似文献
962.
Cognitive map theory assumes that novel environmental information is automatically incorporated into existing cognitive maps
as a function of exploration. Reports of blocking in place learning cast doubt on this claim. In these studies, subjects were
first trained to find a place, using a set of landmarks (Set A). Then novel landmarks (Set B) were added for additional trials.
Subsequent removal of the Set A landmarks showed that the novel landmarks alone were insufficient for successful navigation.
We investigated whether instructing human subjects to explore the environment can moderate blocking. First, we demonstrated
that blocking is absent in a computer implementation of the Morris water maze (MWM) in which subjects are instructed to explore.
We then studied why others found blocking in a different MWM implementation, in which the task instructions did not suggest
exploration. In experiments that faithfully replicated this MWM variant, we found that subjects did not acquire cognitive
maps and that blocking was attenuated when instructions were provided that encouraged exploration. Together, these findings
indicate that blocking in human place learning may reflect a performance deficit, not a learning deficit, and that instructions
can moderate blocking. Our results thus support the automatic update assumption of cognitive map theory. 相似文献
963.
Scafoglieri A Tresignie J Provyn S Clarys JP Bautmans I 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(1):100-108
Introduction
The determination of lipid biomarkers by capillary sampling may be useful in the screening, diagnosis and/or personal management of hyperlipidemia and cardiovascular risk. It remains unclear whether the use of the Accutrend® Plus system is appropriate. This study aimed to assess its reproducibility, accuracy and concordance for blood lipid profiling in adults.Materials and methods:
Fasting capillary total cholesterol (TC) and triglyceride (TG) concentration on Accutrend® Plus were compared with their venous analogues obtained by a laboratory reference method in sixty-one adults (27 men and 34 women, aged 33.0 years). Supplementary capillary sampling was performed at two consecutive days taking into account macro-nutrient intake.Results:
The day-to-day reproducibility of the Accutrend® Plus system proved to be high for TC (ICC = 0.85, P < 0.001), but moderate for TG (ICC = 0.68, P < 0.001). Strong correlations (r ≥ 0.80, P < 0.001) with the reference method were found for TC and TG. Mean difference (limits of agreement) were: 0.26 mmol/L (−0.95, 1.47) for TC, and −0.16 mmol/L (−1.29, 0.98) for TG. The concordance for subject classification according to the National Cholesterol Education Program (NCEP) guidelines was significant (P < 0.001), with substantial agreement for TC (κw = 0.67), and moderate agreement for TG (κw = 0.50).Conclusions:
Day-to-day reproducibility of the Accutrend® Plus device for TC and TG is not optimal and lacks accuracy when compared to the reference laboratory method. The concordance between both methods for classifying subjects according to the NCEP is inadequate. Accutrend® Plus device should not be interchangeably used as a substitution for the standard laboratory methods in the diagnosis of hyperlipidemia. 相似文献964.
Khoshmanesh K Akagi J Hall CJ Crosier KE Crosier PS Cooper JM Wlodkowic D 《Biomicrofluidics》2012,6(2):24102-2410214
The lack of technologies that combine automated manipulation, sorting, as well as immobilization of single metazoan embryos remains the key obstacle to high-throughput organism-based ecotoxicological analysis and drug screening routines. Noticeably, the major obstacle hampering the automated trapping and arraying of millimetre-sized embryos on chip-based devices is their substantial size and mass, which lead to rapid gravitational-induced sedimentation and strong inertial forces. In this work, we present a comprehensive mechanistic and design rationale for manipulation and passive trapping of individual zebrafish embryos using only hydrodynamic forces. We provide evidence that by employing innovative design features, highly efficient hydrodynamic positioning of large embryos on a chip can be achieved. We also show how computational fluid dynamics-guided design and the Lagrangian particle tracking modeling can be used to optimize the chip performance. Importantly, we show that rapid prototyping and medium scale fabrication of miniaturized devices can be greatly accelerated by combining high-speed laser prototyping with replica moulding in poly(dimethylsiloxane) instead of conventional photolithography techniques. Our work establishes a new paradigm for chip-based manipulation of large multicellular organisms with diameters well above 1 mm and masses often exceeding 1 mg. Passive docking of large embryos is an attractive alternative to provide high level of automation while alleviating potentially deleterious effects associated with the use of active chip actuation. This greatly expands the capabilities of bioanalyses performed on small model organisms and offers numerous and currently inaccessible laboratory automation advantages. 相似文献
965.
The effects of carbohydrate ingestion on the badminton serve after fatiguing exercise 总被引:1,自引:1,他引:0
The badminton serve requires great skill and may be affected by fatigue. The aim of the present study was to determine whether carbohydrate ingestion affects badminton performance. Nine male badminton players (age 25 ± 7 years, mass 80.6 ± 8.0 kg) attended the laboratory on three occasions. The first visit involved an incremental exercise test to exhaustion to determine peak heart rate. Participants were given 1 L of a carbohydrate-electrolyte drink or a matched placebo during the experimental trials. The accuracy of 10 long and 10 short serves was determined before and after exercise. The fatiguing exercise was 33 min in duration (83 ± 10% and 84 ± 8% peak heart rate for the placebo and carbohydrate trial respectively). Capillary blood samples (20 μL) were taken before and after exercise for determination of blood glucose and lactate. There was deterioration in long serve accuracy with fatigue (P = 0.002), which carbohydrate ingestion had a tendency to prevent (P = 0.077). There was no effect of fatigue (P = 0.402) or carbohydrate ingestion (P = 0.109) on short serve accuracy. There was no difference in blood glucose concentration between trials (P = 0.851). Blood lactate concentration was higher during the placebo trial (P = 0.016). These results suggest that only the long serve is influenced by fatigue and carbohydrate had a tendency to prevent the deterioration in performance. 相似文献
966.
Oliver McGarr 《British journal of educational technology : journal of the Council for Educational Technology》2009,40(6):1094-1108
This literature review explores the historical development of information and communication technology (ICT) in Irish postprimary/secondary schools and examines how the education system has responded to the various ICT initiatives and policy changes. The review has found that despite national policy and significant ICT initiatives, it appears that the use of computer technology has instead evolved independent of these changes. The various policy nudges throughout the past three decades have had limited impact on the nature of its use. The predominant use of the technology lies within discrete informatics subjects which tend to focus on learning about the technology rather than learning with it. Future ICT policy needs to be cognisant of the past, particularly how national ICT initiatives are mediated within schools and the powerful influence of the prevailing ICT culture on external ICT initiatives. 相似文献
967.
A fiercely contested debate in teaching reading concerns the respective roles and merits of reading schemes and real books. Underpinning the controversy are different philosophies and beliefs about how children learn to read. However, to some extent debates have largely been rhetoric‐driven, rather than research‐driven. This article provides a theoretical perspective derived from instructional psychology and explores the assumptions that have been made about the use of real books and reading schemes, which have tended to polarise arguments about their respective strengths and limitations. It analyses the structures of adult literature, children’s real books, and reading schemes, and examines the demands that they make on children’s sight vocabulary and phonic skills. The critical high‐frequency words and grapheme–phoneme correspondences (GPCs) are identified that will enable children to read the majority of phonically regular and irregular words that they encounter which, perhaps surprisingly, occur more often in real books than structured reading schemes. Learning additional sight words or GPCs is of limited value due to their relatively low occurrence in written English and, thus, potentially minimal impact on children’s reading. Finally, the implications of this research for teaching reading are considered, particularly the complementary roles of real books and teaching methods derived from instructional psychology. In the past they have been viewed as diametrically opposed and mutually exclusive. 相似文献
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