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1.
2.
This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow
through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction
by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional.
The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature
field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs. 相似文献
3.
本研究采用Sharma等人编制的<教师融合教育自我效能感量表>以及<融合教育忧虑量表>对上海市110名特殊教育学校教师以及213名普通学校教师进行了调查,结果发现:两类教师对开展融合教育具有一定水平的自我效能感;特殊教育学校教师的自我效能感要高于普通学校教师;普通学校教师在开展融合教学以及与他人合作方面的自我效能感普遍低于特殊教育学校教师,但在行为管理方面,则与特殊教育学校教师没有差异;两类教师对开展融合教育抱有中等水平的忧虑,且融合教育自我效能感与其忧虑水平存在显著负相关,教师对开展残疾学生教学的自信心水平越高,则对融合教育的忧虑越少.教师融合教育忧虑程度对自我效能感的方差贡献率超过50%以上. 相似文献
4.
Derek A. Muller Manjula D. Sharma John Eklund Peter Reimann 《Instructional Science》2007,35(6):519-533
Recent research on principles of best practice for designing effective multimedia instruction has rarely taken into account
students’ alternative conceptions, which are known to strongly influence learning. The goal of this study was to determine
how well students of quantum mechanics could learn ‘vicariously’ by watching a student-tutor dialogue based on alternative
conceptions. Two video treatments were created to summarize key aspects of quantum tunneling, a fundamental quantum mechanical
phenomenon. One video depicted a student-tutor dialogue, incorporating many of the common alternative conceptions on the topic,
and resolving inconsistencies in reasoning through discussion. The other presented the same correct physics material in an
expository style without alternative conceptions. Second year physics students were randomly assigned to one of the two treatments
and were tested before and after watching the video during a lecture. Results show a statistically significant (p < .01) advantage for the learners in the dialogue treatment (d = 0.71). Follow-up interviews of students yielded insight into the affective and cognitive benefits of the dialogue video. 相似文献
5.
J. Baxi Kavita Sharma Rajbala Asha Mehta A. K. Pendse P. P. Singh 《Indian journal of clinical biochemistry : IJCB》1994,9(1):47-49
Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one. 相似文献
6.
ABSTRACTIncreasingly intense, multifaceted, and integrated forms of surveillance are a central feature of Western national security attempts to counter the violence of “Islamic terrorism.” However, there has been a lack of research examining contemporary regimes of surveillance as profoundly racialized. This study examines how counterterrorism efforts are underpinned by ill-conceived accounts of radicalization that preemptively construct Muslim migrants as a threat to national security, thereby justifying practices of mass surveillance that further propagate racist discourses of uncertainty and risk. We advance an analysis of a racialized surveillant assemblage, which is generative of mutable, algorithmically determined profiles of the Muslim-as-terrorist. Such a regime of mass surveillance effectively puts all Muslims under suspicion. We highlight that, paradoxically, mass data-mining operations stifle, rather than aid, the identification of actual terrorist threats. This conditions a paranoid surveillant racism, through which Muslim populations become modulated as an unknowable threat of death and destruction. 相似文献
7.
Stakeholder perspectives on barriers and facilitators of inclusive education in the Solomon Islands 下载免费PDF全文
Umesh Sharma Tim Loreman Janine Simi 《Journal of Research in Special Educational Needs》2017,17(2):143-151
This paper reports perceived barriers and facilitators of disability‐inclusive education, and outcomes of an effective system of inclusive education in the Solomon Islands. Data were gathered from a variety of stakeholder group participants (n = 10) and individual key informants (n = 2), ranging from parents of children with disabilities to government representatives. The results revealed a unique perspective on disability‐inclusive education in this context, and provided insight into possible directions towards a more inclusive system. 相似文献
8.
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
9.
The effect of peer feedback for blogging on college students' reflective learning processes 总被引:1,自引:0,他引:1
Reflection is an important prerequisite to making meaning of new information, and to advance from surface to deep learning. Strategies such as journal writing and peer feedback have been found to promote reflection as well as deep thinking and learning. This study used an empirical design to investigate the interaction effects of peer feedback and blogging on college students' reflective thinking skills and their learning approaches. Forty-four first- and second-year undergraduate students participated in the study. Students kept blogs each week throughout a whole semester. Two journals were sampled at the beginning and end of the semester for each student. A repeated measure one-way ANOVA suggested that students' reflective thinking level increased significantly over time; however, peer feedback was found to negatively affect students' reflective thinking skills. The result of the study suggests more carefully designed uses in the future. 相似文献
10.
Ajay Kumar D. H. Shah M. G. R. Rajan U. R. Thakare S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164
An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related
hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum
workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short
oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples
from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of
the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The
inter laboratory %CV for T3, T4 and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first
phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T3, T4 and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances
of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as
percent laboratories having desirable or acceptable results for T3, T4 and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment
thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed
helps in improving the performance. 相似文献