Impacts of contextual and explicit instruction on preservice elementary teachers' understandings of the nature of science

This mixed‐methods investigation compared the relative impacts of instructional approach and context of nature of science instruction on preservice elementary teachers' understandings. The sample consisted of 75 preservice teachers enrolled in four sections of an elementary science methods course. Independent variables included instructional approach to teaching nature of science (implicit vs. explicit) and the context of nature of science instruction (as a stand‐alone topic vs. situated within instruction about global climate change and global warming). These treatments were randomly applied to the four class sections along a 2 × 2 matrix, permitting the comparison of outcomes for each independent variable separately and in combination to those of a control group. Data collection spanned the semester‐long course and included written responses to pre‐ and post‐treatment administrations of the VNOS‐B, semi‐structured interviews, and a variety of classroom artifacts. Qualitative methods were used to analyze the data with the goal of constructing profiles of participants' understandings of the nature of science and of global climate change /global warming (GCC/GW). These profiles were compared across treatments using non‐parametric statistics to assess the relative effectiveness of the four instructional approaches. Results indicated that preservice teachers who experienced explicit instruction about the nature of science made statistically significant gains in their views of nature of science regardless of whether the nature of science instruction was situated within the context of GCC/GW or as a stand‐alone topic. Further, the participants who experienced explicit nature of science instruction as a stand‐alone topic were able to apply their understandings of nature of science appropriately to novel situations and issues. We address the implications of these results for teaching the nature of science in teacher preparation courses. © 2010 Wiley Periodicals, Inc., Inc. J Res Sci Teach 48: 414–436, 2011     

Listening to grandmothers

In this column, three proud grandmothers share their unique stories and eloquently describe the transforming experience of becoming a grandmother and the joy associated with witnessing their daughters giving birth.     

Does cardiopulmonary resuscitation cause rib fractures in children? A systematic review

BACKGROUND: There is a diagnostic dilemma when a child presents with rib fractures after cardiopulmonary resuscitation (CPR) where child abuse is suspected as the cause of collapse. We have performed a systematic review to establish the evidence base for the following questions: (i) Does cardiopulmonary resuscitation cause rib fractures in children? (ii) If so, what are the frequency and characteristics of these fractures that may help to distinguish them from rib fractures caused by physical abuse? METHODS: We performed a literature search of original articles, references, textbooks, and conference abstracts, published in any language from 1950 to 1 October 2005. Articles were identified from ASSIA, Caredata, Medline, Ovid Medline in Process, ChildData, CINAHL, Embase, ISI Proceedings, SIGLE, Science Citation Index, Social Science Citation Index, and TRIP databases. We included all studies that addressed rib fractures and CPR in children less than 18 years, and excluded review articles, expert opinion, consensus guidelines, and studies that were significantly methodologically flawed on critical appraisal. Each study underwent two independent reviews (with a third review if there was disagreement). Each reviewer used standardized criteria for study definition, data extraction, and critical appraisal, to determine the quality of the study and to establish if it met the inclusion criteria of this systematic review. FINDINGS: Of the 427 studies reviewed, 6 were included: 1 case control, 4 cross-sectional, and 1 case series. These represent data on 923 children who underwent CPR. Three children sustained rib fractures as a result of resuscitation; all three of these had fractures that were anterior (two mid-clavicular and one costo-chondral). We did not find any child in the literature who had a posterior rib fracture due to CPR. Resuscitation was performed variably by both medical and non-medical personnel. CONCLUSION: Rib fractures after cardiopulmonary resuscitation are rare. When they do occur, they are anterior and may be multiple. As the studies performed to date did not use the most sensitive techniques for detecting rib fractures, further prospective studies of children would be valuable to provide additional clarification on this question.     

Using compositional data analysis to explore accumulation of sedentary behavior,physical activity and youth health

Purpose:The study aimed to describe youth time-use compositions,focusing on time spent in shorter and longer bouts of sedentary behavior and physical activity(PA),and to examine associations of these time-use compositions with cardiometabolic biomarkers.Methods:Accelerometer and cardiometabolic biomarker data from 2 Australian studies involving youths 7-13 years old were pooled(complete cases with accelerometry and adiposity marker data,n=782).A 9-component time-use composition was formed using compositional data analysis:time in shorter and longer bouts of sedentary behavior;time in shorter and longer bouts of light-,moderate-,or vigorous-intensity PA;and"other time"(i.e.,non-wear/sleep).Shorter and longer bouts of sedentary time were defined as<5 min and>5 min,respectively.Shorter bouts of light-,moderate-,and vigorous-intensity PA were defined as<1 min;longer bouts were defined as≥1 min.Regression models examined associations between overall time-use composition and cardiometabolic biomarkers.Then,associations were derived between ratios of longer activity patterns relative to shorter activity patterns,and of each intensity level relative to the other intensity levels and"other time",and cardiometabolic biomarkers.Results:Confounder-adjusted models showed that the overall time-use composition was associated with adiposity,blood pressure,lipids,and the summary score.Specifically,more time in longer bouts of light-intensity PA relative to shorter bouts of light-intensity PA was significantly associated with greater body mass index z-score(zBMI)(β=1.79;SE=0.68)and waist circumference(β=18.35,SE=4.78).When each activity intensity was considered relative to all higher intensities and"other time",more time in light-and vigorous-intensity PA,and less time in sedentary behavior and moderate-intensity PA,were associated with lower waist circumference.Conclusion:Accumulating PA,particularly light-intensity PA,in frequent short bursts may be more beneficial for limiting adiposity compared to accumulating the same amount of PA at these intensities in longer bouts.     

High-throughput study of alpha-synuclein expression in yeast using microfluidics for control of local cellular microenvironment

Microfluidics is an emerging technology which allows the miniaturization, integration, and automation of fluid handling processes. Microfluidic systems offer low sample consumption, significantly reduced processing time, and the prospect of massive parallelization. A microfluidic platform was developed for the control of the soluble cellular microenvironment of Saccharomyces cerevisiae cells, which enabled high-throughput monitoring of the controlled expression of alpha-synuclein (aSyn), a protein involved in Parkinson's disease. Y-shaped structures were fabricated using particle desorption mass spectrometry-based soft-lithography techniques to generate biomolecular gradients along a microchannel. Cell traps integrated along the microchannel allowed the positioning and monitoring of cells in precise locations, where different, well-controlled chemical environments were established. S. cerevisiae cells genetically engineered to encode the fusion protein aSyn-GFP (green fluorescent protein) under the control of GAL1, a galactose inducible promoter, were loaded in the microfluidic structure. A galactose concentration gradient was established in the channel and a time-dependent aSyn-GFP expression was obtained as a function of the positioning of cells along the galactose gradient. Our results demonstrate the applicability of this microfluidic platform to the spatiotemporal control of cellular microenvironment and open a range of possibilities for the study of cellular processes based on single-cell analysis.     

Current and potential use of fresh frozen cadaver in surgical training and anatomical education

As surgical procedures continue to be more complex, the need for more effective training in anatomy has increased. The study of anatomy plays a significant role in the understanding of the human body as well as in basic and advanced clinical training. Among the different cadaver models, fresh frozen cadavers (FFCs) are known for their realistic tissue quality. The purpose of this article was to review and summarize the preparation procedures for and reported cases involving FFCs. PubMed, Scopus, Medline, and Web of Science were searched for relevant studies. The preparation procedures were divided into five steps: washing, irrigation, freezing, defrosting, and arterial infusion. Not all steps were reported to be mandatory, but omitting one or more could result in a loss of quality. FFCs were reported to be used for various purposes: undergraduate education, general surgery training, vascular surgery training, minimal access surgery (laparoscopic surgery) training, and microsurgery training. In all categories, expert opinions and statistical analyses indicated successful outcomes. The reasons for high satisfaction with FFCs included realistic texture, capability of reenacting actual operations, and accuracy of anatomical locations. The results also revealed the importance and advantages of the dissection courses in surgical training. Since the direct comparison between cadaver models is insufficient, future studies regarding this topic are deemed necessary. In addition, it would be advantageous to develop methods to improve FFC quality, or ideas to optimize this model for certain purposes.     

One‐year teaching internships and the dimensions of beginning teacher development

The authors draw on data from weekly e‐mail responses to a questionnaire completed by beginning teachers placed in one‐year, paid, internships. Interns were assigned mentors who responded every several weeks, also via e‐mail, to a questionnaire about the interns and their development. Data from 23 interns were analyzed. Seven themes were identified that capture various dimensions of intern development. To portray the nature, direction and complexity of intern development, each of the dimensions is conceptualized in terms of opposable orientations to the defining aspect of each theme. The authors use the dimensions and their related orientations to organize the data for discussion. Conclusions related to each dimension are situated within the wider research literature on teacher development, and some similarities and differences are noted between this group of interns and what is widely reported about beginning teacher development.

One‐year teaching internships and the dimensions of beginning teacher development

All authors

Robert V. Bullough, Jr * , Janet Young & Roni Jo Draper

https://doi.org/10.1080/1354060042000224124

Published online:

04 August 2006

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