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81.
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   
82.
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   
83.
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   
84.
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   
85.

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests  相似文献   
86.
87.
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.
Maria KordakiEmail:
  相似文献   
88.
Two studies investigated 3- to 6-year-olds' and adults' (N= 128) knowledge about emotions and behaviors caused by thinking about the future because of the past. Participants listened to stories featuring characters that experienced negative events, and then, many days later, felt worried or changed their behaviors upon seeing an entity associated with the prior harm. Results revealed a significant increase between 3 and 5 years in the frequency that participants explained characters' reactions as caused by anticipating the reoccurrence of a negative past event. Across age, females more often marked future events as uncertain, as well as predicted that people in ambiguous risk situations would feel worried due to past-to-future connections.  相似文献   
89.
As they conduct the practical work of collaborating during meetings, nonprofit stakeholders construct, negotiate, and manage identities. In this article we use membership categorization analysis to explore how meeting participants avow and ascribe cultural identities during collaborative meetings in two nonprofit organizations. Examination of identification practices, including employing labels for ethnic categories and implicating cultural identities through category-relevant predicates—which are part of the practical work of collaborating in nonprofit organizations—can serve as an aid to understanding how stakeholders negotiate interorganizational collaboration in social interaction.  相似文献   
90.
    
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