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71.
Village Elders’ and Secondary School Students’ Explanations of Natural Phenomena in Papua New Guinea
Soikava?Pauka David?F.?TreagustEmail author Bruce?Waldrip 《International Journal of Science and Mathematics Education》2005,3(2):213-238
This research investigated the sources of explanations and understanding of natural phenomena in terms of the students’ cultural and school science experiences. The first phase involved interviews with eight village elders that probed their explanations and understanding of natural phenomena. The second phase involved the design, development and administration of two questionnaires on natural phenomena to 179 students in a rural boarding high school in Papua New Guinea (PNG). Most village elders gave explanations of many of the phenomena in terms of spirits, spells, magic, religion, and personal experiences. Most school-aged students choose scientific explanations of natural phenomena in terms of what they had learned in school or from personal experiences. However, many choose explanations of the same phenomena about spirits, spells and magic that came from the village, family or home. The study revealed that students’ ideas about natural phenomena are strongly governed and controlled by their school science knowledge in the school setting. It is likely that their own traditional knowledge cannot be identified in a school setting but that questionnaires in the students’ local language be given to students in their villages (as opposed to school). In addition, so as not to diminish the value of this traditional knowledge, science education programs are needed that are able to consider and harmonise traditional knowledge with school science. 相似文献
72.
Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion. 相似文献
73.
This paper addresses a neglected topic in the knowledge management literature: how the size of a network of actors affects the nature of intra-network social relations and knowledge processes. It makes a theoretical contribution to developing understanding in this area drawing on a range of literatures including practice-based perspectives on knowledge, the literature on the embeddedness of social relations, and relevant knowledge management literature. The central focus of this paper is on the relationship between network size, network density, and how these variables affect intra-network knowledge processes. It suggests that as network size increases network density is likely to decrease (as it becomes problematic for the actors in such networks to retain strong ties with a significant proportion of the network's members), which it will be suggested has significant ramifications for intra-network knowledge processes. This paper concludes by reflecting on the implications of the ideas developed for network-based forms of organizing, and innovation processes. 相似文献
74.
Surapon?TangvarasittichaiEmail author Patcharin?Pingmuanglaew Orathai?Tangvarasittichai 《Indian journal of clinical biochemistry : IJCB》2016,31(4):446-451
Hypertension is the most common cardiovascular risk factor. Lipoprotein(a) [Lp(a)], inflammation, oxidative stress and chronic kidney disease (CKD) exacerbate the response to tissue injury and acts as markers of the vascular disease, especially in glomerulosclerosis. We compared the clinical characteristics of 138 non-diabetes hypertensive women (ndHT) patients with 417 non-diabetes normotensive subjects and tested the association of hypertension with Lp(a), inflammation, CKD and oxidative stress by using multiple logistic regression. BP, BMI, waist circumference, creatinine, Lp(a), inflammation and malondialdehyde levels were significantly higher and CKD state in the ndHT patients (p < 0.05). Multiple logistic regression showed hypertension associated with increased Lp(a), inflammation, ORs and 95 % CIs were 2.52 (1.33, 4.80), 2.75 (1.44, 5.27) after adjusting for their covariates. Elevated serum Lp(a) and inflammation levels concomitants with increased oxidative stress and CKD were the major risk factors associated with hypertension and implications for the increased risk of HT and vascular disease. 相似文献
75.
Evrikleia?Tsagala Maria?KordakiEmail author 《Education and Information Technologies》2007,12(4):281-295
This paper aims to determine the factors affecting the decisions of both male and female secondary school pupils whether or
not to pursue undergraduate studies in Computing. It is based on research conducted in Greece, on a sample of 248 pupils,
135 of whom were female. All were aged 17 and about to decide on their future undergraduate studies. Questionnaires were used,
addressing issues in the following four main categories: a) the reasons pupils chose/rejected Computing, b) how family and
friends, the media and the school environment contribute to their decision, c) how pupils perceived their future after studying
Computing and d) how pupils perceived the profile of a computer professional in terms of gender.
相似文献
Maria KordakiEmail: |
76.
We document some basic facts about how liquids behave in the low gravity of outer space and how this poses challenges to space
scientists and engineers who need to design and test systems that handle fluids in outer space while working in the 1-g environment
on Earth.
N Ananthkrishnan is Director, Coral Digital Technologies (P) Ltd, a Bangalore-based company working in the area of multidisciplinary
simulation and system integration of aerospace, naval and surface vehicles, and in the design and development of autonomous
unmanned/micro air vehicles. 相似文献
77.
Children use the presence of familiar objects with known names to identify the correct referents of novel words. In natural environments, objects vary widely in salience. The presence of familiar objects may sometimes hinder rather than help word learning. To test this hypothesis, 3-year-olds (N = 36) were shown novel objects paired with familiar objects that varied in their visual salience. When the novel objects were labeled, children were slower and less accurate at fixating them in the presence of highly salient familiar objects than in the presence of less salient familiar objects. They were also less successful in retaining these word-referent pairings. While familiar objects may facilitate novel word learning in ambiguous situations, the properties of familiar objects matter. 相似文献
78.
Amy M. Magnus Jenny S. West Daniel W. Scott Cheryl Maxson Jody Miller 《Journal of Criminal Justice Education》2019,30(2):223-249
This paper describes our efforts to systematically generate knowledge from ethnographic and other qualitative scholarship as a way of bridging intellectual gaps found in quantitative research. We ground this scholarly endeavor in the study of gangs, which has a lengthy history in the field of criminology, yet lacks a coherent, coordinated, and comparative understanding of gang dynamics, behavior, and impacts. We discuss the importance of acknowledging the multiple and mixed methodologies used in gang scholarship and detail the inductive, deductive, and iterative process that helped us (1) develop a comprehensive coding instrument for coding a range of qualitative works, (2) establish the instrument’s inter-rater reliability, and (3) remain cognizant and reflexive about the strengths of both quantitative and qualitative research. Finally, we share the critical yet informative challenges we faced throughout the project and conclude with reflections on why the project was unsuccessful in the way we originally envisioned. 相似文献
79.
Financial and cultural aspects of corporate giving by UK and non-UK companies in response to the December 2004 South Asia Tsunami disaster are explored in this article. Literatures on corporate giving rationales, concepts of disaster and donor activity in disasters provide an underpinning. The article seeks to make connections between this high profile if short-lived business giving and the funding of the arts that is sought from business; and to draw tentative lessons for arts funding when seeking business support. The giving accounts in the wake of the Tsunami from a non-probability sample1 of 56 UK companies and 16 non-UK companies were examined. Reported online to the UK charity Business in the Community, these accounts were accessed in February 2005 and scrutinized thematically. Concurrently, company financial profiles to accompany giving figures were constructed. Although linkages between donation levels and financial performance were lacking, emerging themes included the role of employees, influencing company giving and creating a climate of expectation of firms' contributions. These developments may have important implications for business funding for the arts, where leading philanthropists are prominent as individuals in the giving landscapes; but employees' collective involvement is not marked. Alternatively, cultivation of employees as would-be donors, indirectly via their firms, may be a more secure, if lower level route to funding for some arts organizations than dependence on high profile business leaders. The article considers alternative scenarios for company giving in disaster contexts, including as a sustained and lasting giving theme or as company support as a ‘one-off’ event, rock-star style. The likely development of employee power as a key element in company giving is explored; and its wider meanings for funding in arts settings, (where the giver as rock star heroine/hero is also prominent) are considered. 相似文献
80.
Good community consultation is a powerful tool in developing new museum projects and exhibitions, facilitating a more effective delivery of service to a diverse public. Existing techniques for both user and community consultation are limited with front end evaluation particularly undeveloped in the sector, often providing no meaningful base by which to compare project outcomes. Tension exists between government, which values quantitative data, and researchers who argue qualitative methods are more appropriate for evaluating community projects. This article reports a pilot study using the repertory grid technique to examine a ‘socially excluded’, ethnically diverse local community's perceptions, expectations and previous experiences of similar projects, to provide a benchmark against which to compare outcomes. This research formed part of the front end evaluation for a New Deal for Community's Project run by Sheffield Galleries and Museums Trust. The repertory grid technique was developed in psychological studies as a means of understanding respondents' own world views, and is particularly helpful in working with people with poor language skills. Although this study only used the technique qualitatively, it can be used to combine both quantitative and qualitative data, providing more robust data for evidence-based policy decisions. Using the repertory grid technique, respondents were able to list both perceived and practical barriers to participation in projects. The technique also enabled them to articulate what would motivate them to become involved in future projects. The repertory grid technique has significant potential for use in community consultation and project evaluation as a means of understanding local residents' perceptions and its visual representation means that its findings can be easily understood by participants, policy-makers and practitioners. 相似文献