西安住宅室内空气中醛酮类污染物特征

采用主动式气体采样、2,4-DNPH二硝基苯肼吸收、高效液相色谱（HPLC）分析研究了西安市冬、夏两季三所普通居民住宅室内、外空气中13种醛酮类化合物。结果表明：冬、夏两季西安地区住宅室内空气中醛酮类污染物浓度水平均较高。其中,夏季室内、外空气中13种醛酮类化合物总质量浓度为85.86±30.33 µg•m-3和78.86±31.40 µg•m-3,冬季为85.40±28.50 µg•m-3和53.77±16.39 µg•m-3;室内均高于室外;甲醛、乙醛、丙酮为最高组分,三者为总质量的75~80%;三所住宅中,2号住宅（H2）醛类污染物严重,表明装修材料（木地板）与吸烟均有一定程度贡献。     

The Roles of Group Status and Group Membership in the Practice of Hypodescent

Hypodescent emerged in U.S. history to reinforce racial hierarchy. Research suggests that among contemporary U.S. adults, hypodescent continues to shape social perception. Among U.S. children, however, hypodescent is less likely to be endorsed. Here, we tested for hypodescent by introducing U.S. children (ages 4–9) and adults (N = 273) to hierarchically ordered novel groups (one was high status and another was low status) and then to a child who had one parent from each group. In Study 1, we presented the groups in a third-party context. In Study 2, we randomly assigned participants to the high-status or the low-status group. Across both studies, participants did not reliably endorse hypodescent, raising questions as to what elicits this practice.     

Low-cost,disposable microfluidics device for blood plasma extraction using continuously alternating paramagnetic and diamagnetic capture modes

Blood plasma contains biomarkers and substances that indicate the physiological state of an organism, and it can be used to diagnose various diseases or body condition. To improve the accuracy of diagnostic test, it is required to obtain the high purity of blood plasma. This paper presents a low-cost, disposable microfluidics device for blood plasma extraction using magnetophoretic behaviors of blood cells. This device uses alternating magnetophoretic capture modes to trap and separate paramagnetic and diamagnetic cells away from blood plasma. The device system is composed of two parts, a disposable microfluidics chip and a non-disposable (reusable) magnetic field source. Such modularized device helps the structure of the disposable part dramatically simplified, which is beneficial for low-cost mass production. A series of numerical simulation and parametric study have been performed to describe the mechanism of blood cell separation in the microchannel, and the results are discussed. Furthermore, experimental feasibility test has been carried out in order to demonstrate the blood plasma extraction process of the proposed device. In this experiment, pure blood plasma has been successfully extracted with yield of 21.933% from 75 μl 1:10 dilution of deoxygenated blood.     

Singapore: Review of Educational Events in 1994 and 1995

The period under review, 1994-1995, is best regarded as one of consolidation with some fine-tuning following the adoption of a range of educational initiatives in the preceding three years. As reported in the earlier two reviews in 1992 and 1993 (in the Singapore Journal of Education), some of these initiatives stemmed from the recommendations of the report entitled Improving Primary School Education (1991). Refinements made to other aspects of the education system were also announced in the period under review. All these refinements principally ensure that the central aim of the education system continues to be achieved.     

Prevalence,gender ratio and gender differences in reading‐related cognitive abilities among Chinese children with dyslexia in Hong Kong

Based on the data of the normative study of the Hong Kong test of specific learning difficulties in reading and writing, and the Test of visual‐perceptual skills (non‐motor)—Revised, 99 children aged between 6 and 10½ years were identified as children with dyslexia out of the normative sample of 690 children. By excluding 12 children known to score below average in IQ, 87 children, including 20 children not tested for IQ, could be regarded as children with dyslexia, yielding a prevalence rate of 12.6% and a boy:girl gender ratio of 1.6 to 1. The figures would become 9.7% and 2.0 to 1 if the 20 children were omitted from computation. However, gender imbalance could not be readily explained by gender differences in reading‐related cognitive abilities, as there were only minor and subtle differences. Regression analyses to evaluate the relative contribution of different cognitive abilities to reading and writing suggested that orthographic knowledge and naming speed were most important among children with dyslexia. Implications of the findings and the need for early intervention are discussed.     

The Follow-Up Studies Project: A Brief Report

Studies following up on student teachers who have started full-time teaching constitute part of the programme evaluation scheme at the Institute of Education. Since 1982 two surveys have been conducted to find out the perceptions that former Certificate and Diploma students had of their training programmes and whether there was any noticeable shift in their views about teaching.     

Variations in Practice Reading Aloud: Ten Versus Twenty Minutes

In this study we compared effects of practice time reading aloud to an adult on improvement in reading rate and comprehension. Eighty-one poor readers in 2nd and 4th grade, including 38 English Learner students (ELs), served as their own controls by participating in two practice conditions, each 3 times per week for 7 weeks: (a) 10 min reading aloud one-to-one to an adult listener and (b) 20 min reading aloud one-to-one. Repeated measures analysis of variance showed that 20 min of practice was better than 10 min for 4th graders, but not for 2nd graders, and gains in rate accelerated across the 14 weeks of practice. We found no differences in rate gains across conditions between ELs and native English speakers. After controlling for pretests, reading rate at posttest, along with vocabulary, contributed significant variance to reading comprehension outcomes.     

The place and approach of outdoor learning within a holistic curricular agenda: development of Singaporean outdoor education practice

This paper details the potential contribution of outdoor education (OE) in Singaporean education given the recent raft of national curricular reforms aimed at fostering holistic and exploratory learning opportunities. In this context, we contend that increasing recognition of the value of OE, both internationally and locally, heralds specific challenges within unique Singaporean educational conditions that must be taken into account for this subject area to flourish. In particular, we seek to distil the ways in which local community, cultural and school conditions signal the need for a more place-based and contextualised version of OE. Our analysis further addresses the need for adequate professional development frameworks to be installed in order to enhance existing local teachers’ capacities to substantially educate pupils through the outdoors, within a Southeast Asian urban context.