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261.
Katherine I. Martin 《Reading and writing》2017,30(2):279-298
Orthographic knowledge, the general ability to learn, store, and use information about the orthographic form of words (Stanovich & West, 1989), is a crucial skill for supporting literacy. Although the development of first language (L1) orthographic awareness is impacted by the characteristics of a learner’s L1 writing system, relatively little is known about what impact the L1 may have on second language (L2) orthographic awareness. In this study, English language learners from three L1s (French, Hebrew, Mandarin Chinese), plus L1 English speakers, were tested on their English spelling knowledge using a word-pseudohomophone discrimination task. In addition to allowing for the cross-linguistic comparisons, items were designed to examine whether learners had differing performance on pseudohomophones (misspellings) that targeted vowels versus consonants. Consistent with previous research (e.g., McBride-Chang, Bialystok, Cong, & Li, 2004), the L1 Chinese speakers had the highest (L2) accuracy, followed by the L1 Hebrew and the L1 French speakers. The participants from non-alphabetic languages (Hebrew and Chinese) had significantly lower accuracy on items with misspellings involving vowels compared to consonants, and the size of the vowel-consonant accuracy difference varied substantially across L1 groups. The results demonstrate that the characteristics of a learner’s L1 writing system, particularly the existence of vowel and consonant graphemes, impact the development of L2 orthographic knowledge and sensitivity to different types of word misspellings. 相似文献
262.
To improve the aerodynamic performance of high-speed trains (HSTs) running in the open air, a multi-objective aerodynamic optimization design method for the head shape of a HST is proposed in this paper. A parametric model of the HST was established and seven design variables of the head shape were extracted. Sample points and their exact values of optimization objectives were obtained by an optimal Latin hypercube sampling (opt. LHS) plan and computational fluid dynamic (CFD) simulations, respectively. A Kriging surrogate model was constructed based on the sample points and their optimization objectives. Taking the total aerodynamic drag force and the aerodynamic lift force of the tail coach as the optimization objectives, the multi-objective aerodynamic optimization design was performed based on a non-dominated sorting genetic algorithm-II (NSGA-II) and the Kriging model. After optimization, a series of Pareto-optimal head shapes were obtained. An optimal head shape was selected from the Pareto-optimal head shapes, and the aerodynamic performance of the HST with the optimal head shape was compared with that of the original train in conditions with and without crosswinds. Compared with the original train, the total aerodynamic drag force is reduced by 2.61% and the lift force of the tail coach is reduced by 9.90% in conditions without crosswind. Moreover, the optimal train benefits from lower fluctuations in aerodynamic loads in crosswind conditions. 相似文献
263.
Anthony L. Brown 《The Urban Review》2009,41(5):436-435
Drawing from ethnographic data, this paper explores how African American male teachers working with African American male
students performed their pedagogy. This paper highlights how teachers’ understanding of African American males social and
educational needs shaped their pedagogical performance. Interestingly however, teachers’ performance was contingent on the
diverse ways they imagined African American males should engage within their social and political worlds. These findings suggest
then that African American male teachers’ pedagogic performances were both complex and multifaceted. 相似文献
264.
265.
It is widely recognized that metacognition is an important mediator for successful and high-level learning, especially in
higher education. Nevertheless, a majority of higher education students possess insufficient metacognitive knowledge and regulation
skills to self-regulate their learning adequately. This study explores the potential of reciprocal peer tutoring to promote
both university students’ metacognitive knowledge and their metacognitive regulation skills. The study was conducted in a
naturalistic higher education setting, involving 67 students tutoring each other during a complete semester. A multi-method
pretest–posttest design was used combining a self-report questionnaire, assessing students’ metacognitive knowledge and their
perceived metacognitive skilfulness, with the analysis of think-aloud protocols, revealing students’ actual use of metacognitive
strategies. Results indicate no significant pretest to posttest differences in students’ metacognitive knowledge, nor in their
perception of metacognitive skill use. In contrast, significant changes are observed in students’ actual metacognitive regulation.
At posttest, students demonstrate significantly more frequent and more varied use of metacognitive regulation, especially
during the orientation, monitoring, and evaluation phases. Furthermore, our findings point to an increase in more profound
and higher-quality strategy use at posttest. 相似文献
266.
This article analyses academic work and the academic workforce in the context of current dynamics and likely futures. It discusses the significance of academic work, reviews workforce characteristics, and analyses tensions and pressures. Prevailing conceptualisations, it is argued, do not reflect the current situation in which the profession finds itself, and would provide a very shaky foundation on which to build the future workforce. There is an overarching need for a fresh conceptualisation of academic work that is authentic and feasible and suggestions are offered of what this might look like. A number of strategies are proposed how such a recasting might be implemented. The paper works from Australian research, and make suggestions for other systems. 相似文献
267.
Analyzing interdisciplinarity: Typology and indicators 总被引:1,自引:0,他引:1
Both funding agencies and scholars in science studies have become increasingly concerned with how to define and identify interdisciplinarity in research. The task is tricky, since the complexity of interdisciplinary research defies a single definition. Our study tackles this challenge by demonstrating a new typology and qualitative indicators for analyzing interdisciplinarity in research documents. The proposed conceptual framework attempts to fulfill the need for a robust and nuanced approach that is grounded in deeper knowledge of interdisciplinarity. As an example of using the framework, we discuss our empirical investigation of research proposals funded by a national funding agency in Finland. 相似文献
268.
Noëmi Manders-Huits 《Ethics and Information Technology》2010,12(1):1-2
Over the past decade Identity Management has become a central theme in information technology, policy, and administration
in the public and private sectors. In these contexts the term ‘Identity Management’ is used primarily to refer to ways and
methods of dealing with registration and authorization issues regarding persons in organizational and service-oriented domains.
Especially due to the growing range of choices and options for, and the enhanced autonomy and rights of, employees, citizens,
and customers, there is a growing demand for systems that enable the regulation of rights, duties, responsibilities, entitlements
and access of innumerable people simultaneously. ‘Identity Management’ or ‘Identity Management Systems’ have become important
headings under which such systems are designed and implemented. But there is another meaning of the term ‘identity management’,
which is clearly related and which has gained currency. This second construal refers to the need to manage our moral identities
and our identity related information. This paper explores the relation between the management of our (moral) identities and
‘Identity Management’ as conceptualized in IT discourse. 相似文献
269.
Singh PP Chandra A Mahdi F Roy A Sharma P 《Indian journal of clinical biochemistry : IJCB》2010,25(3):225-243
The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers
nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality
clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality.
Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive
conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques
are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double
blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit
answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge
superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body
increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor
have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial
infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants,
including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive
oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own
requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal
requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience
the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body
can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about
optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring
plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic
purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l
and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established.
The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective
antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency.
The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing
population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution
in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant
behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy,
diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits
of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation
in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others
possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to
non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop
stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good. 相似文献
270.
In view of the risk of E-commerce and the response of the insurance industry to it, this paper is aimed at one important point of insurance, that is, estimation of financial loss ratio, which is one of the most difficult problems facing the E-insurance industry. This paper proposes a quantitative analyzing model for estimating E-insurance financial loss ratio. The model is based on gross income per enterprise and CSI/FBI computer crime and security survey. The analysis results presented are reasonable and valuable for both insurer and the insured and thus can be accepted by both of them. What we must point out is that according to our assumption, the financial loss ratio varied very little, 0.233% in 1999 and 0.236% in 2000 although there was much variation in the main data of the CSI/FBI survey. 相似文献