187 research outputs found

    Police and Social Workers as Members of New Crisis-Management Teams

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    A variety of programs have emerged of late which involve the close collaboration and cooperation of police and social workers in order to deal with family crises. By pooling their respective skills and resources, police and social workers hope to respond more effectively to the diverse situations and challenges presented by family crises. Several of these programs are reviewed here and one is probed in depth. Also, various questions are raised regarding some of the possible problems associated with this kind of collaboration

    Using student difficulties to identify and model factors influencing the ability to interpret external representations of IgG-antigen binding.

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    Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.Scientific external representations (ERs), such as diagrams, images, pictures, graphs and animations are considered to be powerful teaching and learning tools, because they assist learners in constructing mental models of phenomena, which allows for the comprehension and integration of scientific concepts. Sometimes, however, students experience difficulties with the interpretation of ERs, which· has a negative effect on their learning of science, including biochemistry. Unfortunately, many educators are not aware of such student difficulties and make the wrong assumption that what they, as experts, consider to be an educationally sound ER will necessarily promote sound learning and understanding among novices. On the contrary, research has shown that learners who engage in the molecular biosciences can experience considerable problems interpreting, visualising, reasoning and learning with ERs of biochemical structures and processes, which are both abstract and often represented by confusing computer-generated symbols and man-made markings. The aim of this study was three-fold. Firstly, to identify and classify students' conceptual and reasoning difficulties with a selection of textbook ERs representing· IgG structure and function. Secondly, to use these difficulties to identify sources of the difficulties and, therefore, factors influencing students' ability to interpret the ERs. Thirdly, to develop a model of these factors and investigate the practical applications of the model, including guidelines for improving ER design and the teaching and learning with ERs. The study was conducted at the University of KwaZulu-Natal, South Africa and involved a total of 166 second and third-year biochemistry students. The research aims were addressed using a postpositivistic approach consisting of inductive and qualitative research methods. Data was collected from students by means of written probes, audio- and video-taped clinical interviews, and student-generated diagrams. Analysis of the data revealed three general categories of student difficulties, with the interpretation of three textbook ERs depicting antibody structure and interaction with antigen, termed the process-type (P), the structural-type (S) and DNA-related (D) difficulties. Included in the three general categories of difficulty were seventeen sub-categories that were each classified on the four-level research framework of Grayson et al. (2001) according to how much information we had about the nature of each difficulty and, therefore, whether they required further research. The incidences of the classified difficulties ranged from 3 to 70%, across the student populations and across all three ERs. Based on the evidence of the difficulties, potential sources of the classified difficulties were isolated. Consideration of the nature of the sources of the exposed difficulties indicated that at least three factors play a major role in students' ability to interpret ERs in biochemistry. The three factors are: students' ability to reason with an ER and with their own conceptual knowledge (R), students' understanding (or lack thereof) of the concepts of relevance to the ER (C), and the mode in which the desired phenomenon is represented by the ER (M). A novel three-phase single interview technique (3P-SIT) was designed to explicitly investigate the nature of the above three factors. Application of 3P-SIT to a range of abstract to realistic ERs of antibody structure and interaction with antigen revealed that the instrument was extremely useful for generating data corresponding to the three factors. In addition analysis of the 3P-SIT data showed evidence for the influence of one factor on another during students' ER interpretation, leading to the identification of a further four interactive factors, namely the reasoning-mode (R-M), reasoning conceptual (R-C), conceptual-mode (C-M) and conceptual-reasoning-mode (C-R-M) factors. The Justi and Gilbert (2002) modelling process was employed to develop a model of the seven identified factors. Empirical data generated using 3P-SIT allowed the formulation and validation of operational definitions for the seven factors and the expression of the model as a Venn diagram. Consideration of the implications of the model yielded at least seven practical applications of the model, including its use for: establishing whether sound or unsound interpretation, learning and visualisation of an ER has occurred; identifying the nature and source of any difficulties; determining which of the factors of the model are positively or negatively influencing interpretation; establishing what approaches to ER design and teaching and learning with ERs will optimise the interpretation and learning process; and, generally framing and guiding researchers', educators' and authors' thinking about the nature of students' difficulties with the interpretation of both static and animated ERs in any scientific context. In addition, the study demonstrated how each factor of the expressed model can be used to inform the design of strategies for remediating or preventing students' difficulties with the interpretation of scientific ERs, a target for future research

    Nonlinear Bias and the Convective Fisher Equation

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    We combine random walks, growth and decay, and convection, in a Monte Carlo simulation to model 1D interface dynamics with fluctuations. The continuum limit corresponds to the deterministic Fisher equation with convection. We find qualitatively the same type of asymmetry, as well as velocity difference, for interface profiles moving in opposite directions. However a transition apparent in the mean-field (continuum) limit is not found in the Monte Carlo simulation.Comment: 2.5 pages (texed) with 4 postscript figures, TeX 3.14t

    Evolutionary aesthetics as a meeting point of philosophy and biology

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    Metaphysics, or the knowledge of what there is, has been traditionally placed at the pinnacle of philosophical hierarchy. It was followed by theory of knowledge, or epistemology. Practical knowledge of proper modes of conduct, ethics, came third, followed by aesthetics, treated usually in a marginal way as having to do only with the perception of the beautiful. The hierarchy of philosophical disciplines has recently undergone a substantial transformation. As a result, ethics has assumed a central role. The aim of this paper is to suggest that the hierarchy of philosophical disciplines is not yet complete and that one further step needs to be taken. According to the claim advocated here, it is not metaphysics, epistemology or ethics, but aesthetics that is the first and foremost of all philosophical disciplines. This claim is argued for by references to findings of evolutionary aesthetics, especially to Charles Darwin's idea of sexual selection as elaborated in The Descent of Man. I also argue that Darwinian approach to morality is, and should be, derivable from an Darwinian aesthetics which lies at the core of his conception of sexual selection

    Effects of electromagnetic fields emitted by GSM phones on working memory:a meta-analysis

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    Background and Objective: Current treatments for Alzheimer's Disease (AD) do not affect the course of the illness and brain stimulation techniques are increasingly promoted as potential therapeutic inter-ventions for AD. This study reviews the effects of electromagnetic ïŹeld (EMF) exposure versus sham exposure on working memory (WM) performance of healthy human participants. Method: Online literature databases and previous systematic reviews were searched for studies of EMF and WM in participants without reported memory problems. Two thousand eight hundred and ïŹfty seven studies were identiïŹed, and 10 studies met the inclusion criteria. An assessment of study quality was completed, and separate, random effects meta-analyses were conducted for each of the three WM tasks included: n-back, substitution and digit span forward. Results: No differences were found between participants exposed to active EMF versus sham conditions in any of the three working memory tasks examined. Conclusion: Results indicate that EMF does not affect WM during the n-back, substitution and digit-span tasks. Future studies should focus on the possible effects of chronic exposure to EMF in older adults with AD using a battery of comparable WM and attention tasks, before EMF can be seriously considered as a potential modulator of WM in AD

    Characteristics and help-seeking behavior of people failing a smart device self-test for hearing

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    PURPOSE : This study investigated user characteristics, help-seeking behavior, and follow-up actions of people who failed an app-based digits-in-noise hearing screening test, considering their stage of change. METHOD : Test and user characteristics of 3,092 listeners who failed the test were retrospectively analyzed. A posttest survey determining follow-up (verb) actions was sent to listeners who failed the test (n = 1,007), of which 59 responded. RESULTS : The majority of listeners were in the precontemplation stage (75.5%). Age and stage of change were significant (p < .05) predictors of the digits-in-noise speech recognition threshold (DIN SRT). Listeners in the precontemplation stage were significantly younger than in other stages (p < .05). Posttest survey response rate was low (5.9%). Of those, most (82.4%) did not think they had a hearing loss. Only 13.6% followed up with an audiologist. CONCLUSION : Older people presented with poorer DIN SRTs and were typically in a more advanced stage of change. The majority of those who did not follow up after failing the screening test did not believe they had a hearing loss. A combination of factors, including poor DIN SRT, older age, and a more advanced stage of change inclined participants to follow up with audiological care.https://pubs.asha.org/journal/ajahj2021Speech-Language Pathology and Audiolog

    Physical Models Can Provide Superior Learning Opportunities Beyond the Benefits of Active Engagements

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    The essence of molecular biology education lies in understanding of gene expression, with subtopics including the central dogma processes, such as transcription and translation. While these concepts are core to the discipline, they are also notoriously difficult for students to learn, probably because they cannot be directly observed. While nearly all active learning strategies have been shown to improve learning compared with passive lectures, little has been done to compare different types of active learning. We hypothesized that physical models of central dogma processes would be especially helpful for learning, because they provide a resource that students can see, touch, and manipulate while trying to build their knowledge. For students enrolled in an entirely active-learning-based Cell & Molecular Biology course, we examined whether model-based activities were more effective than non-model based activities. To test their understanding at the beginning and end of the semester, we employed the multiple-select Central Dogma Concept Inventory (CDCI). Each student acted as their own control, as all students engaged in all lessons yet some questions related to model-based activities and some related to clicker questions, group problem-solving, and other non-model-based activities. While all students demonstrated learning gains on both types of question, they showed much higher learning gains on model-based questions. Examining their selected answers in detail showed that while higher performing students were prompted to refine their already-good mental models to be even better, lower performing students were able to construct new knowledge that was much more consistent with an expert\u27s understanding

    Polyphasic taxonomy of Aspergillus section Candidi based on molecular, morphological and physiological data

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    Aspergillus section Candidi historically included a single white-spored species, A. candidus. Later studies clarified that other species may also belong to this section. In this study, we examined isolates of species tentatively assigned to section Candidi using a polyphasic approach. The characters examined include sequence analysis of partial ÎČ-tubulin, calmodulin and ITS sequences of the isolates, morphological and physiological tests, and examination of the extrolite profiles. Our data indicate that the revised section Candidi includes 4 species: A. candidus, A. campestris, A. taichungensis and A. tritici. This is strongly supported by all the morphological characteristics that are characteristic of section Candidi: slow growing colonies with globose conidial heads having white to yellowish conidia, conidiophores smooth, small conidiophores common, metulae present and covering the entire vesicle, some large Aspergillus heads with large metulae, presence of diminutive heads in all species, conidia smooth or nearly so with a subglobose to ovoid shape, and the presence of sclerotia in three species (A. candidus, A. taichungensis and A. tritici). Aspergillus tritici has been suggested to be the synonym of A. candidus previously, however, sequence data indicate that this is a valid species and includes isolates came from soil, wheat grain, flour and drums from India, Ghana, Sweden, The Netherlands and Hungary, making it a relatively widespread species. All species produce terphenyllins and candidusins and three species (A. candidus, A. campestris and A. tritici) produce chlorflavonins. Xanthoascins have only been found in A. candidus. Each of the species in section Candidi produce several other species specific extrolites, and none of these have been found in any other Aspergillus species. A. candidus has often been listed as a human pathogenic species, but this is unlikely as this species cannot grow at 37 °C. The pathogenic species may be A. tritici or white mutants of Aspergillus flavus

    A Model for Using a Concept Inventory as a Tool for Students' Assessment and Faculty Professional Development

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    This essay describes how the use of a concept inventory has enhanced professional development and curriculum reform efforts of a faculty teaching community. The Host Pathogen Interactions (HPI) teaching team is composed of research and teaching faculty with expertise in HPI who share the goal of improving the learning experience of students in nine linked undergraduate microbiology courses. To support evidence-based curriculum reform, we administered our HPI Concept Inventory as a pre- and postsurvey to approximately 400 students each year since 2006. The resulting data include student scores as well as their open-ended explanations for distractor choices. The data have enabled us to address curriculum reform goals of 1) reconciling student learning with our expectations, 2) correlating student learning with background variables, 3) understanding student learning across institutions, 4) measuring the effect of teaching techniques on student learning, and 5) demonstrating how our courses collectively form a learning progression. The analysis of the concept inventory data has anchored and deepened the team's discussions of student learning. Reading and discussing students' responses revealed the gap between our understanding and the students' understanding. We provide evidence to support the concept inventory as a tool for assessing student understanding of HPI concepts and faculty development
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