Posing Problems for Open Investigations: What questions do pupils ask?

The purpose of this study was to (a) find out the types of questions that pupils ask for open-ended science investigations, and (b) discuss how teachers can help pupils to identify problems and pose questions that are feasible for investigations. The study was conducted in a class of 39 primary 6 pupils of mixed ability. The pupils wrote down questions for two investigations that they would like to work on. The questions for the first investigation were generated individually, but those for the second investigation were posed in groups after the pupils were shown some examples of investigable questions. Among the questions that were posed individually, only 11.7% could be answered by performing hands-on investigations. Most of the questions asked were based on general knowledge and covered a wide range of topics. However, when questions were generated in groups after examples were shown, there was a significant increase in the number of questions that were amenable to science investigations (71.4%) but they related to fewer topics. A typology of investigable and non-investigable questions is proposed. Suggestions on how teachers can help pupils to pose problems and questions that are feasible for investigations are given.     

低效水驱稠油油藏蒸汽吞吐热采可行性论证——以林东馆三段出砂强敏感稠油油藏为例

稠油油藏水驱采收率低,因其原油黏度高,不适合转化学驱,但转热采可大幅提高采收率。林樊家油田林东馆三段地质条件复杂,地层敏感性强,供液差,产能低,油稠,出砂严重,多年来采用了各种工艺措施,均未取得好的水驱开采效果。在分析低效水驱原因的基础上,论证了水驱转蒸汽热采可行性。开发实践表明,低效水驱稠油油藏通过转热采可大幅提高采收率,同时研究成果对同类油藏的开发具有重要指导意义。     

Effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) levels

Abstract

We investigated the effects of an acute bout of exercise on serum soluble leptin receptor (sOB-R) concentrations. Eighteen male participants completed two different exercise sessions with intensities of 25% and 65% maximal aerobic capacity (VO₂max). In addition to the energy expenditure during exercise sessions being measured, blood samples were collected before exercise, and immediately, at 24 h, and at 48 h post-exercise to analyse sOB-R, leptin and insulin levels. At 24 h post-exercise, sOB-R and leptin concentrations at the 65% VO₂max were significantly different from those at the 25% VO₂max. Leptin levels at 48 h post-exercise were also significantly lower for the 65% VO₂max than for the 25% VO₂max (P < 0.01). In the 65% VO₂max session, the energy expenditure during exercise was significantly associated with leptin concentrations at 24 h and 48 h and sOB-R concentrations at 24 h post-exercise. However, no correlations were found between sOB-R and leptin at the three post-exercise time points. In conclusion, an acute bout of exercise with 920 kcal of output resulted in an increase in sOB-R levels at 24 h post-exercise. However, the changes in sOB-R levels due to an acute bout of exercise might not contribute to the delayed decrease observed for leptin.     

Tunable spatial heterogeneity in structure and composition within aqueous microfluidic droplets

In this paper, we demonstrate biphasic microfluidic droplets with broadly tunable internal structures, from simple near-equilibrium drop-in-drop morphologies to complex yet uniform non-equilibrium steady-state structures. The droplets contain an aqueous mixture of poly(ethylene glycol) (PEG) and dextran and are dispensed into an immiscible oil in a microfluidic T-junction device. Above a certain well-defined threshold droplet speed, the inner dextran-rich phase is "stirred" within the outer PEG-rich phase. The stirred polymer mixture is observed to exhibit a near continuum of speed and composition-dependent phase morphologies. There is increasing interest in the use of such aqueous two-phase systems in microfluidic devices for biomolecular applications in a variety of contexts. Our work presents a method to go beyond equilibrium phase morphologies in generating microfluidic "multiple" emulsions and at the same time raises the possibility of biochemical experimentation in benign yet complex biomimetic milieus.     

The motivation to study: an analysis of undergraduate engineering students at a Caribbean university

The link between motivation and success is well documented; however, there is still room to problematise motivation in regards to the individual and contextual levels. This study looks at motivation in relation to students studying undergraduate engineering courses at a Caribbean university and seeks to discover the factors that motivate them to study and the factors that keep them motivated. An online questionnaire was constructed using 19 Likert-type questions and 5 questions that allowed for open-ended qualitative responses. The findings reveal that participants tended to be motivated by the increased possibility of desired future careers and tended to stay motivated by a combination of goal-orientation and family support. It is recommended that departments, faculties and institutions deliberate on shared and contextually constructed understandings of why students choose to enrol in particular university courses.     

Diagnostic Laboratories in India: Investigating Quality Characteristics,Productivity and Time of Reporting

This is the result of a Survey of diagnostics laboratories in the Asia Pacific (APAC) region with perspectives on India, investigating the three key aspects that are central to the success of a laboratory: quality, cost and speed. This Survey provides a comparison in selected performance indicators in a large number of diagnostic laboratories in a broad range of countries in the APAC region. The Survey provides data on some key performance characteristics such as quality improvement activities, staff productivity and Turnaround Time (TAT). This Survey also demonstrates in India the common issues facing all the laboratories surveyed but also common solutions using a Quality Systems approach which involves Accreditation, customer responsiveness, greater use of IT, automation and Lean principles. Indian laboratories reported less automation and fewer laboratories have Laboratory Information Systems. The productivity by various measures in Indian laboratories was less than in other APAC laboratories. TAT was more commonly monitored in the Indian specimens though there were fewer laboratories compared with the APAC specimens where there were separate TATs for Short Turnaround Time and Routine specimens.     

伞形科植物染色体数目报告

 Chromosome numbers are reported for 26 species and varieties of Umbelliferae which belong to 3 subfamilies and 19 genera in this paper.  Of these, 13 counts are new records and some problems about chromosome numbers of Umbelliferae are simplydiscussed.     

Learning residential electrical wiring through computer simulation: The impact of computer‐based learning environments on student achievement and cognitive load

Multimedia learning environments such as computer simulations are widely accepted as tools for supporting science learning. Although the design of multimedia learning environments can be domain specific, few studies have focused on the use of computer simulations for learning residential electrical wiring. This study aimed to determine whether students using computer simulations learned better than traditional classroom learners in the domain of residential wiring. A quasi‐experiment was implemented with 169 high school students. The simulation group participated in a series of computer simulations, whereas the control group received lectures and demonstrations from an instructor. Students' cognitive load as elevated by multimedia leaning tasks was compared with that of students learning using traditional methods. The simulation group learned significantly better and reported higher cognitive load than did the control group. Moreover, the simulation group managed cognitive resources more efficiently on transfer of learning than did the control group. Having more opportunities to interact with a simulation‐based learning environment could result in higher cognitive load. The higher cognitive load seemed to result in better performance on the achievement test and, therefore, the learners' mental effort was possibly invested mainly in meaning making in the virtual learning environments. Discussion of the results, instruments and research design, as well as suggestions for future studies are provided.     

Maternal Parenting Stress,Child Exuberance,and Preschoolers’ Behavior Problems

This study investigated whether child exuberance, an aspect of temperament related to emotion regulation, moderates the well-documented association between high parenting stress and increased risk for internalizing and externalizing problems during the preschool years. At 42 months of age child exuberance was observed in 256 children (47% girls) and maternal self-reports on parenting stress were obtained. At 48 months internalizing and externalizing problems were assessed through reports from both parents. Indeed, higher maternal parenting stress increased the risk for internalizing problems, and this association was more pronounced among children with high levels of exuberance. Existent emotion regulation difficulties in highly exuberant children may further heighten the risk conveyed by an unfavorable caregiving environment for developing internalizing problems.