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521.
This paper examines the social, organisational and individual factors that may affect students' acceptance of e‐learning systems in higher education in a cross‐cultural context. A questionnaire was developed based on an extended technology acceptance model (TAM). A total sample of 1173 university students from two private universities in Lebanon and one university in England participated in this study. After performing the satisfactory reliability and validity checks, the hypothesised model was estimated using structural equation modeling. The findings of this study revealed that perceived usefulness (PU), perceived ease of use (PEOU), social norms (SNs), perceived quality of work life (QWL), computer self‐efficacy (SE) and facilitating conditions (FC) are significant determinants of behavioural intentions (BIs) and usage of e‐learning system for the Lebanese and British students. QWL, the newly added variable, was found the most important construct in explaining the causal process in the model for both samples. Differences were found between Lebanese and British students with regard to PEOU, SN, QWL, FC, SE and actual usage; however, no differences were detected in terms of PU and BI. Overall, the proposed model achieves acceptable fit and explains for 69% of the British sample and 57% of the Lebanese sample of its variance which is higher than that of the original TAM. Our findings suggest that individual, social and organisational factors are important to consider in explaining students' BI and usage of e‐learning environments.  相似文献   
522.
The aim of this study is to evaluate the oxidative stress in predialysis, hemodialysis (HD) and peritoneal dialysis patients and to test the effects of antihypertensive drugs and volume control on oxidative stress parameters. The study was composed of five groups as follows: control group (n = 30), predialysis group (n = 30), peritoneal dialysis group (n = 30), hemodialysis group, (normotensive with strict volume control, n = 30), hemodialysis group (normotensive with medication, n = 30). Plasma malondialdehyde (MDA), erythrocyte superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) and routine biochemical parameters were studied in all patients. Hemodialysis patients with strict volume control (HDvc) had lower levels of MDA than other patient groups (p < 0.001), and CAT, SOD values had highest level other patient groups (p < 0.001). The treatment of hypertension with strict volume control in chronic renal failure patients causes less damage to the antioxidant capacity.  相似文献   
523.
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   
524.
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   
525.
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   
526.
This paper concerns the simultaneous fault detection and control (SFDC) problem for a class of nonlinear stochastic switched systems with time-varying state delay and parameter uncertainties. The switching signal of detector/controller unit (DCU) is assumed to be with switching delay, which results in the asynchronous switching between the subsystems and DCU. By constructing a switching strategy depending on the state and switching delays, new sufficient conditions expressed by a set of linear matrix inequalities (LMIs) is derived to design DCU gains. This problem is formulated as an H optimization problem and both mean square exponential stability and fault detection of augmented system are considered. A numerical example is finally exploited to verify the effectiveness and potential of the achieved scheme.  相似文献   
527.
This study examines and compares word of mouth (WOM) behaviour among university students in Syria. To date, little is known about this important phenomenon which is surprising given the deregulated education market in Syria that allows for private universities to compete for students alongside public universities. Using a mixed methods research design and structural equation modelling, our results show faculty individualised attention and student satisfaction were found to be positively related to university image. Further, student satisfaction and university image were found to be direct sources of students’ positive WOM behaviour. We found a moderating effect of university ownership type on university image. Interestingly, we identified six themes showing how support staff empathy could be seen as a source of low student satisfaction. These were defined as deception/credibility/soft‐soapers/suspiciousness: when support staff coax something out of students; confusion/role conflict: resulting from the diverse roles played by support staff while interacting with students; unfairness: when a student notices discrimination in the level of empathy between their peers; privacy: when support staff empathy can be perceived as a kind of intrusion; self‐congratulatory: when a support staff member shows off or praises their empathy; and support staff/student ratio: when this ratio is seen to be small, the empathy effect reverses.  相似文献   
528.
Background and purpose: The perception of aging is one of the independent predictors of functional disability and mortality in the aged ones, this study was conducted to compare the follow-up of a training program with the use of two in-person and telenursing methods on the perception of aging of the elderly, covered by the comprehensive health centers in Ahvaz city.

Materials and Methods: This quasi-experimental study involved systematic random sampling conducted on 60 elderly persons (aged 60–75 years) who were referred to in Ahvaz. A training program was conducted for all elderly persons for 3 weeks (three sessions per week), which was accompanied with 2 months of six follow-ups for the telephonic follow-up group (Tele-nursing), and two follow-ups for in-person follow-up group. The data were collected with the use of demographic form, Abbreviated Mental Test (AMT), and The Brief Aging Perceptions Questionnaire (B-APQ). Elderly completed the questionnaire at the beginning of the study and 8 weeks later. The data were subsequently analyzed with SPSS software; and P values less than 0.05 were considered significant.

Results: Based on the results, the mean score of perception of aging increased in the study groups after the intervention. This increase was statistically significant only in the intervention group.

Discussion and Conclusion: The telephonic follow-up was more effective on Increasing the perception of aging compared with the in-person follow-up. Therefore, using this method is recommended for the elderly.  相似文献   
529.
In most developing countries, that are confronted, as we know, with so many complex problems, no one can deny that the most important are those of education and training.  相似文献   
530.
The present study was to examine the effects of personal and university bounded factors in students mental health in north of Fars province, Iran. The effects of these factors on university students' psychopathology within a survey design were investigated among 300 participants--94 males and 206 females, who were selected through random sampling method and the degrees of their mental health, were measured by SCL-90-R checklist. Overall findings supported that gender, marital status, socioeconomic status as personal factors, and type of university as within university factor would influence students' mental health. So males, married, and students with moderate and high socioeconomic status had more significant better mental health situation than females, singles and those with low socioeconomic status. Finally, ethnicity, dormitory and non-dormitory residence, native or non-native being, discipline, school and faculty, and academic performance variables were not effective on students' mental health significantly. Here, it was suggested an explanatory triangle model for university students' mental health explanation with respect to gendered and socio-cultural contexts and their implications in clinical and educational settings.  相似文献   
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