A preliminary study on the effectiveness of inquiry-based activities for addressing misconceptions of undergraduate engineering students

This paper presents results from a preliminary study of the effectiveness of using inquiry-based activities to address misconceptions held by undergraduate engineering students in heat transfer and thermodynamics. These targeted misconception areas were identified previously as both important and difficult for students to master by a panel of engineering educators. Five separate inquiry-based activities (two physical experiments and three computer simulations) were developed and tested for their effectiveness at producing conceptual change during a 4-year study. Students’ conceptual change was assessed with concept inventories used in a pre-test–post-test design. The research examined students’ ability to answer conceptual questions both directly coupled with the developed activity and questions that required students to apply the targeted concept in new contexts. These assessments were done both immediately after the activity and 10 weeks later. Students’ performance generally improved in all areas, suggesting that the activities were effective for promoting conceptual change.     

Inclusionary housing policy: a tool for re-shaping South Africa’s spatial legacy?

In South Africa, recent initiatives to restructure cities towards greater compaction and integration include the formulation of an inclusionary housing policy, where private property developers are expected to offer some affordable housing in their developments. This paper examines policy and practice in the City of Johannesburg where an inclusionary housing policy is intended to work together with a growth management strategy to direct infrastructural investment. However the policy has hardly been used. The paper examines the policy and its development, initiatives to use it, and the challenges it faces. Key constraints include: resistance by the property development industry and middle/upper-income residents; South Africa’s huge income inequalities and hence housing price cliffs; and institutional and legal issues. These concerns have in part underpinned the lack of supportive national policy. In this context, local policies have been confined to specific, deal-driven projects, but these have also been fraught with problems, and have delivered few affordable units. The potential of inclusionary housing policy for reshaping South African cities therefore seems limited, although it could play a small role if national policy with careful attention to implementation were formulated. An alternative form of mixed income developer-led housing seems to have greater potential, although it is focused on low/middle-income housing and relies to a significant extent on government subsidies, in contrast to inclusionary housing proper.     

Distribution,Abundance, and Range of the Round Goby,Apollina melanostoma,in the Duluth-Superior Harbor and St. Louis River Estuary, 1998–2004

Round gobies were first discovered in the Duluth-Superior Harbor, Lake Superior, in 1995. Anecdotal sightings by anglers and others suggested that the infestation was growing and expanding; however, direct evidence of the distribution and expansion rate in the harbor was largely unknown. Distribution and range of the round goby, Apollonia melanostoma, (formerly Neogobius melanostomus) was assessed using bottom trawl sampling throughout the Duluth-Superior Harbor, and portions of the lower St. Louis River from 1998 to 2004. Previous to 1998, round gobies only were reported to occupy the harbor between the two shipping entries (river kilometer 1 to 7). By 2004, they expanded throughout the harbor and upstream to river kilometer 13, but remained absent in western Lake Superior. The number of round gobies captured per 5 minutes of trawling (catch per unit effort, CPUE) increased from less than 1 fish in 1998 to an average 5.4 ± 1.2 SE fish in 2004, indicating a large increase in the population. The median yearly fish total length varied from 56.0 to 81.5 mm and wet weight varied from 2.3 to 7.0 g. As nest guarding male round gobies were located in rocky habitats inaccessible to trawling, the initial years were dominated by female round gobies with a 16:1 female to male ratio, but by 2002 the maximum ratio was 2:1. The ratio change may be indicative of the increasing population forcing males from their preferred rocky habitat onto open substrates that were more accessible to trawling.     

Effect of a mixture of micronutrients, but not of bovine colostrum concentrate, on immune function parameters in healthy volunteers: a randomized placebo-controlled study

Background  

Supplementation of nutritional deficiencies helps to improve immune function and resistance to infections in malnourished subjects. However, the suggested benefits of dietary supplementation for immune function in healthy well nourished subjects is less clear. Among the food constituents frequently associated with beneficial effects on immune function are micronutrients such as vitamin C, vitamin E, β-carotene and zinc, and colostrum. This study was designed to investigate the effects these ingredients on immune function markers in healthy volunteers.     

The role of the family for behavioral outcome in children and adolescents following traumatic brain injury.

This study assessed the behavioral outcome of 51 children with traumatic brain injury (TBI) up to 2 years following injury. Children with severe injuries, but not those with mild or moderate injuries, were reported by parents to have a greater incidence of behavior problems following TBI. Regression analyses indicated that the presence of a partner for the primary caregiver of the child and the acute emotional reaction of the parent to the injury were both predictive of child behavioral outcome, although not by 2-year follow-up. These findings suggest that parental coping resources may impact on the development of child behavioral sequelae following TBI, emphasizing the role of the family in the child's response and the importance of supportive intervention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Job Stress in the Nursing Profession: The Influence of Organizational and Environmental Conditions and Job Characteristics.

The aim of the current study was to examine the influence of organizational and environmental work conditions on the job characteristics of nurses and on their health and well-being. The sample consisted of 807 registered nurses working in an academic hospital in Leiden (the Netherlands). The direct influence of work conditions on outcomes was examined. Mediation of job characteristics in the relationships between work conditions and outcomes was tested by means of regression analyses. The results indicated that job characteristics, such as demands and control, mediated the relationship between work conditions, such as work agreements/rewards, and outcomes. By managing organizational and environmental conditions of work, job characteristics can be altered, and these in turn influence nurses' job satisfaction and distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dichloromethane-enhanced negative ion chemical ionization for the determination of polychlorinated n-alkanes

The use of dichloromethane/methane reagent gas mixtures is described as an alternative to conventional electron capture negative ionization for the determination of polychlorinated n-alkanes (PCAs). A nearly exclusive formation of [M + Cl]- adduct ions was observed suppressing the generation of other fragment ions. The resulting enhanced selectivity and sensitivity lowered quantification limits to 3 ng for a technical PCA mixture and 10.5-13.5 pg for single congeners. Response factors for congeners of different degrees of chlorination varied by not more than a factor of 2. Interferences from other polychlorinated compounds present in environmental samples such as toxaphene or chlordanes were suppressed by a factor of 5 or more. The technique was applied for the determination of the composition of technical PCA mixtures as well as for the analysis of PCAs in North Sea dab liver.     

Determination of total polychlorinated n-alkane concentration in biota by electron ionization-MS/MS

Electron ionization (EI) tandem mass spectrometry (MS/MS) allowed the fast determination of the total concentration of short- and medium-chained polychlorinated n-alkanes (PCAs) in biota. EI fragment ions common to all PCAs could be identified. Collision-induced dissociations (CIDs) were carried out by ion trap and triple quadrupole EI-MS/MS. CIDs of m/z 91 --> 53 (limit of detection (LOD) 0.15 ng/microL), 102 --> 65 (LOD = 0.2 ng/microL), and 102 --> 67 (LOD = 0.1 ng/microL) were applied for the determination of the total short- and medium-chain PCA concentration in pooled fish liver samples (North Sea dab, cod, flounder) from the North Sea and from the Baltic Sea using both MS technologies. Total PCA concentrations were in the range of 88-607 ng/g. Accuracy was controlled with spiked samples and deviated not more than 15% from expected values.