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521.
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Yildirim Ali 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2004,50(2):157-175
This study investigates the assessment strategies used in social-studies courses at the high-school level in Turkey and examines how teachers and students perceive them. Results indicate that short-answer tests are most frequently used to assess student performance, followed by oral tests. Multiple-choice and essay tests are also occasionally employed. Teachers tend to be satisfied with these assessment strategies, but suggest that alternative modes of assessment should also be considered. Students do not find such tests adequate for assessing their real performance in social-studies courses. 相似文献
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Bandana Kumari Krishnan Hajela Asgar Ali Abhay Kumar Sharma Rajesh Kumar Yadav Alok Ranjan Rathish Nair Shreekant Bharti Satish Dipankar Prabhat Kumar Singh Sadhana Sharma 《Indian journal of clinical biochemistry : IJCB》2023,38(1):102
IntroductionDetecting low viral load has been a challenge in this pandemic, which has led to its escalated transmission. Complement activation has been implicated in pathogenesis of Covid-19 infection. Thus, evaluation of complement activation in suspected Covid-19 infection may help to detect infection and limit false negative cases thus limiting transmission of infection. We speculate that measuring C4b, produced from an activated complement system due to the presence of Covid-19 may help in its detection, even when the viral titers are low.MethodsPlasma C4b levels of symptomatic RT-PCR positive patients (cases, n = 40); symptomatic RT-PCR negative patients (n = 35) and asymptomatic RT-PCR negative controls (n = 40) were evaluated. Plasma C5b-9, IL-6, D-dimer and C1-Inhibitor (C1-INH) were also measured in cases and controls. ELISA kits were used for all measurements. Statistical analyses were carried out using Stata, version 12 (Stata Corp., Texas, USA).ResultsC4b levels were found to be significantly increased in RT-PCR positive patients as compared to asymptomatic RT-PCR negative controls. RT-PCR negative but symptomatic patients still showed increased C4b levels. The significantly higher levels of C4b in cases with a cut-off value of ≥ 116 ng/ml with optimum sensitivity and specificity of 80% and 52% respectively is indicative of its possible use as an adjunct marker. Increased levels of D-dimer, IL6, along with decreased levels of C1-INH were found in cases compared to controls. Whereas, C5b-9 levels were not significantly raised in cases.ConclusionsThe results of our study suggests that plasma C4b may help to detect infection in false negative cases of RT-PCR that escape detection owing to low viral load. However, to confirm it a large-scale study is needed.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12291-022-01033-z. 相似文献
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This paper explores how a group of undergraduate students in the United Arab Emirates (UAE) use their mobile phones to perform
informal learning activities related to the content of their courses outside the classroom. The paper also addresses the usefulness
of informal learning activities to support students’ learning. The study adopts an exploratory case study design and uses
multiple methods of data collection including questionnaires, interviews and diary entries. Main findings suggest that students
performed informal learning activities mostly from home, interacting mainly with classmates. It also shows that students were
in control of their informal learning activities without teachers’ input. However, it was found that students used only a
limited number of applications but these were considered useful to their learning. The paper contributes to a discussion of
the implications of training and instructor support to help students to take more advantage of mobile phone applications to
support informal learning. Recommendations for further research are discussed. 相似文献
525.
目前亲子互动研究成为一个非常重要的课题。父母冲突作为考察亲子互动关系的一个重要变量,逐渐成为研究者关注的重要问题。尽管20世纪70年代以来,国外已从某些角度揭示了父母冲突与儿童发展的关系,并在一定程度上探讨了父母冲突对儿童的影响。但我国目前还没有系统的儿童与父母冲突的研究。因此,从我国的具体情况入手探讨亲子冲突对丰富和发展儿童心理学的基本理论,全面了解并有效促进儿童发展具有重要的理论和实践意义。 相似文献
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Haseeb Ahmad Khan Samia Hasan Sobki Abdullah Saleh Alhomida Shaukat Ali Khan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):65-70
This study reports the utilization of serum fructosamine and blood glucose for the screening of gestational diabetes mellitus
(GDM). Blood samples from 165 pregnant women were analyzed for fasting blood glucose (FBG), random blood glucose (RBG) and
serum fructosamine. The actual fructosamine levels were corrected for serum protein (c-Fruct) for more precise presentation.
Two cut-off values of FBG (>5.3 mmol/L and >7.0 mmol/L) and RBG (>7.8 mmol/L and >11.0 mmol/L) were used to classify hyperglycemic
subjects for subsequent evaluation. The average values±standard deviations for FBG, RBG and cFruct were 5.865±1.95, 7.767±3.21
and 2.387±0.47 mmol/L, respectively. FBG levels were significantly correlated with RBG (Pearson correlation=0.597, P<0.001).
Significant correlations were also observed between cFruct and FBG (Pearson correlation=0.673, P<0.001) or RBG (Pearson correlation=0.641,
P<0.001). Out of 165 subjects, 24 (14.5%) cases were classified as hyperglycemic on the basis of FBG>7.0 mmol/L or RBG>11.0
mmol/L; use of lower cut-off values resulted higher frequencies of hyperglycemia. Whereas, a combined criteria of FBG>5.3
mmol/L and cFruct >2.5 mmol/L predicted 35 patients as the most probable hyperglycemic as compared to 32 patients identified
using the criteria of RBG >7.8 mmol/L and cFruct >2.5 mmol/L. These criteria were associated with 4.8% and 3.6% false-positivity
at the expense of 3.6% and 3.0% false-negative outcomes, respectively. The levels of FBG, RBG and cFruct were significantly
higher in hyperglycemic groups (irrespective of grouping criteria) as compared to the respective normal groups. In conclusion,
these findings clearly indicate that the paired values of cFruct with FBG or RBG could help in filtering high-risk individuals
for OGTT and therefore avoiding a unnecessary OGTT. 相似文献
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