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991.
992.
The authors have developed a first-year fluids course for a class of around 230 aerospace, civil and mechanical engineering students. This paper aims to show how the teaching and assessment methodology was applied to the challenge of a large class. The lectures featured formal teaching interspersed with active learning elements. Smaller group (about 25–30 students) tutorial classes involved student practice. A 10-minute test occurred in each tutorial during weeks 3–11. Each test was based on the previous week's lecture material and the marks contributed towards 20% of the course mark. A condition for passing the course was that a student must pass at least six of the nine tests. The assessment promoted student involvement with the course – tutorial attendance was greater and more uniform than previously and exam performance improved significantly. Students recognised that the assessment system was useful in encouraging continuous learning over the semester and building confidence.  相似文献   
993.
994.
This paper explores how mature female flight attendants [FAs] use Selection, Optimization and Compensation [SOC] strategies to cope with age-related diminishing resources at work. The role of FAs is an age-sensitive occupation, and in some organizations, women are under constant pressure to look young and attractive. This Interpretative Phenomenological Analysis study aims to add depth and nuance to our understanding of SOC strategies qualitatively; most published studies are quantitative. A homogenous sample of 5 mature single Filipina FAs, foreign workers employed by Arabian Gulf-based airlines, were interviewed through a semi-structured protocol. Recruitment was through a snowball process. The study found that FAs use SOC strategies to compensate for age-related decline. Off-duty, their focus is directed to activities that help them to meet the organizations’ expectations of youthful appearance and productivity. To achieve this, resources from other life domains are diverted, which leads to negative outcomes from focusing SOC strategies on only one aspect of life. Despite negative personal implications and concerns about the future, the participants still felt attached to their work identities. This shows the importance of understanding the use of SOC strategies within and across life domains, as well as their implications for career sustainability and workability. The use of such strategies at work when detrimental to other life roles is unsustainable. The findings highlight the importance of conducting more qualitative studies on SOC behaviors of specific groups, so the experiences of aging at work can be explored in more depth, allowing areas of concern to be identified.  相似文献   
995.
The nature of knowledge in vocational education is often described in dichotomies such as theory versus practice or general versus specific. Although different scholars now acknowledge that vocational knowledge is more than putting bits of theoretical and practical knowledge together, it is still unclear how vocational knowledge should be theorised instead. In this article we theorise the idea of contextualising vocational knowledge to understand the nature of vocational knowledge and illustrate this process of contextualising with empirical examples from culinary education. We adopt an activity-theoretical focus on contextualising that involves both particularising and providing coherence. We posit a cognitive process of meaning making where meaning derives from seeing the relationships of parts to the whole. The aspects of the nature of coherence and the relation between concepts and actions seem rather underdeveloped in vocational education theory. To characterise this process at a micro-level, we enhance the activity-theory approach with an inferentialist one. Inferentialism offers a way to focus on reasons and inferential relations between concepts and actions that provides coherence in vocational knowledge. To characterise the broad spectrum of processes relevant for vocational knowledge, we propose the terms “conceptualising” and “concretising”. Conceptualising involves inferring what follows from understanding a concept in a particular situation in relation to the meaning of other concepts. Concretising involves inferring what follows from understanding an aspect of the occupational practice in which students are participating. We argue that this way of framing vocational knowledge helps to better understand its nature and development.  相似文献   
996.
997.
Organic acid disorders are inherited metabolic disorders in which organic acids accumulate in tissues and biological fluids of affected individuals. Classical organic acidurias include methylmalonic aciduria, propionic aciduria, isovaleric aciduria and maple syrup urine disease (MSUD). They are considered the most frequent metabolic disorders among severely ill children. Patients frequently present with acute symptoms early in life. 420 cases clinically suspected to have organic aciduria, with upper age limit of 12 years for a 2-year period (January 2007–December 2008) were enrolled into this study. Metabolic acidosis and neurological symptoms were the most common signs. Screening tests and thin layer chromatography were done for detection of organic acidurias. Identification and quantitation of organic acids in urine and quantification of amino acids in blood were done by high performance liquid chromatography. Out of 420 patients, 45 patients (10.7%) were found to have organic acidurias. 15 cases of methylmalonic aciduria, 16 cases of propionic aciduria, 13 cases of MSUD, and one case of isovaleric aciduria were diagnosed. Results demonstrate the importance of testing for organic acidurias. Since organic aciduria may cause irreversible brain damage if not treated, we recommend selective screening amongst severely ill children despite implied extra costs.  相似文献   
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999.
1000.
The acidification of water leads to disturbances in the water and ion metabolism of fish, including the acid-base balance. Many fish probably possess physiological mechanisms to eliminate these disturbances completely or in part. However successful they may be in the short term, such adaptation mechanisms nevertheless require additional energy, thus causing growth and reproduction to be retarded. Taking into account the high sensitivity of fish eggs and larvae to acidification, these phenomena are probably a major contributory factor to the decline of fish stocks in acidified water.  相似文献   
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