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21.
Maryam Farahnak Zarabi Ali Farhangi Samaneh Khademi Mazdeh Zahra Ansarian Davod Zare Mohammad Reza Mehrabi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(2):154-160
Carboxylate-modified gold nanoparticles (GNPs) were synthesized in a simple one-step process based on the reduction of tetrachloroauric acid by aspartic acid in water. GNPs were identified by UV–Vis spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy. Conjugation of protein molecules with functionalized nanoparticles was performed through electrostatic interaction. The GNP–protein conjugates were characterized by gel electrophoresis. The interaction between functionalized GNPs and protein molecules lead to conformational transition of protein structure after conjugation of protein with GNPs. This process was investigated by fluorescence spectroscopy and circular dichroism spectroscopy. 相似文献
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Ali Farhangi Dariush Norouzian Mohammad Reza Mehrabi Mohsen Chiani Zahra Saffari Maryam Farahnak Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(4):406-417
The objective of this study is to induce experimental diabetes mellitus by streptozotocin in normal adult Wistar rats via comparison of changes in body weight, consumption of food, volume of water, urine and levels of glucose, insulin and C-peptide in serum, between normal and diabetic rats. Intra-venous injection of 60 mg/kg dose of streptozotocin in 250–300 g (75–90 days) adult Wistar rats makes pancreas swell and causes degeneration in Langerhans islet β-cells and induces experimental diabetes mellitus in 2–4 days. For a microscopic study of degeneration of Langerhans islet β-cells of diabetic rats, biopsy from pancreas tissue of diabetic and normal rats, staining and comparison between them, were done. In this process, after collagenase digestion of pancreas, islets were isolated, dissociated and identified by dithizone method and then with enzymatic procedure by DNase and trypsin, the islet cells changed into single cells and β-cells were identified by immune fluorescence method and then assayed by flow-cytometer. Donor tissue in each step of work was prepared from 38 adult male Wistar rats weighted 250–300 g (75–90 days). Transplantation was performed in rats after 2–4 weeks of diabetes induction. In this study, the levels of insulin, C-peptide and glucose in diabetic rats reached to normal range as compared to un-diabetic rats in 20 days after transplantation of islet cells. Transplantation was performed under the cortex of testis as immunoisolated place for islet cells transplantation. 相似文献
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The primary goal of this study was to investigate whether college students’ academic time management could be used to understand their engagement in traditional and active forms of procrastination within a model of self-regulated learning. College students (N = 446) completed a self-report survey that assessed motivational and strategic aspects of self-regulated learning, time management, and procrastination. Results of regression analyses indicated that self-efficacy and metacognitive strategies initially were significant predictors of traditional and active forms of procrastination. Incorporating time management in the analyses increased the amount of the variance explained and, even in the presence of the motivation and strategy variables, time management emerged as an important predictor of both traditional and active forms of procrastination. Findings support the conclusion that academic time management is a key aspect of self-regulated learning and, as such, it can be useful for understanding the extent to which college students procrastinate when doing their academic work. 相似文献
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Maryam Alqassab Jan-Willem Strijbos Stefan Ufer 《European Journal of Psychology of Education - EJPE》2018,33(1):11-30
Peer feedback is widely used to train assessment skills and to support collaborative learning of various learning tasks, but research on peer feedback in the domain of mathematics is limited. Although domain knowledge seems to be a prerequisite for peer-feedback provision, it only recently received attention in the peer-feedback literature. In this study, preservice mathematics teachers (N = 43) were involved in a peer-feedback training in which they evaluated geometric construction tasks and were (a) trained to provide peer feedback on different levels (i.e. task, process and self-regulation) and (b) scaffolded with worked examples, feedback provision prompts and evaluation rubrics during the training. A quasi-experimental mixed design was implemented with domain knowledge as the between-subject factor and measurement occasion as the within-subject factor. Students’ peer-feedback provision skills and their beliefs about peer-feedback provision were measured before and after the training. Students with high and medium domain knowledge provided more peer feedback at the self-regulation level, whereas those low in domain knowledge provided more peer feedback at the task-level after the training. Students’ beliefs about peer-feedback provision became less positive after the training, regardless of the level of their domain knowledge. 相似文献
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Abstract A critical success factor for businesses in the twenty‐first century will be their ability to meet the environmental demands for complex coordination of action and rapid adjustments to volatile markets and global competition. Business teams are effective mechanisms for addressing the need for dynamic, flexible organizations that can effectively cope with complexity and turbulence. Business teams are not a new phenomenon, but there is a new element in the equation: the use of information technologies (IT) to leverage team effort. Information technologies can enhance team performance through support of interaction processes by providing two types of functionality: coordination support and task execution support. An agenda for action for moving forward a team‐based organization and use of information technologies for support of business teams is provided. 相似文献
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Donna King Stephen Ritchie Maryam Sandhu Senka Henderson 《International Journal of Science Education》2013,35(12):1886-1914
Science activities that evoke positive emotional responses make a difference to students’ emotional experience of science. In this study, we explored 8th Grade students’ discrete emotions expressed during science activities in a unit on Energy. Multiple data sources including classroom videos, interviews and emotion diaries completed at the end of each lesson were analysed to identify individual student's emotions. Results from two representative students are presented as case studies. Using a theoretical perspective drawn from theories of emotions founded in sociology, two assertions emerged. First, during the demonstration activity, students experienced the emotions of wonder and surprise; second, during a laboratory activity, students experienced the intense positive emotions of happiness/joy. Characteristics of these activities that contributed to students’ positive experiences are highlighted. The study found that choosing activities that evoked strong positive emotional experiences, focused students’ attention on the phenomenon they were learning, and the activities were recalled positively. Furthermore, such positive experiences may contribute to students’ interest and engagement in science and longer term memorability. Finally, implications for science teachers and pre-service teacher education are suggested. 相似文献
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Shahla Asiri Reza FadayeVatan Maryam Rassouli Ali Montazeri 《Educational gerontology》2013,39(10):636-644
ABSTRACTThe psychosocial theory of Gerotranscendence, is proposing an alternative and positive view of aging and states that human development is a lifelong process. Applying the concept of Gerotranscendence into the older adults’ lives may have the potential to provide a more positive view of aging and a better care for a growing population. First; and to do this, we need to use a proper, valid and reliable measure. The purpose of this cross-sectional and methodological study was to assess the psychometric properties of the Persian version of the short-form Gerotranscendence scale (GS-S) in community-dwelling Iranian older adults. First the scale was translated to Persian, and culturally adapted. Then pre-testing and cognitive interviewing implemented in a sample consisted of 10; and stability of the scale in a sample of 30 older adults, respectively. Confirmatory factor analysis and internal consistency of the scale were done with 250 older adults. The three-factor structure was confirmed. The model showed a good fit, and all the indices were satisfactory (RMSEA = 0.063; NNFI = 0.093; CFI = 0.095; IFI = 0.096; GFI = 0.095; and χ2/df = 2). Cronbach’s alpha of the scale was 0.72 and coefficient omega was 0.82. Test-retest reliability (ICC) was 0.88, P < .001; and standard error of measurement was 1.16 (CI = %95). Minimal detectable change (MDC) was 3.2 and minimal important change (MIC) was 1.4. This study supports the use of the GS-S as a measure of life span development among the Iranian older adults. 相似文献
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Hajar Eftekhari Maryam Pilehchian Langroudi Ali Banihashemi Mandana Azizi Reza Youssefi Kamangar Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(2):231-234
α-Thalassemia (α-thal) is considered as the most common inherited hemoglobin disorder worldwide. The present study describes the first observation of a combination of rare α-chain variants, and β-globin gene cluster deletion. A 21-year-old woman with thalassemia trait, marked microcytosis, mild anemia, and normal range of Hb F was referred to Amirkola genetic center in the North of Iran for routine molecular test of thalassemia in the context of carrier detection and prevention of thalassemia major birth. Nucleotide sequencing revealed a novel compound heterozygosity status for two non-deletional mutations on HBA2, Hb O Indonesia (α116(GH4)Glu → Lys), and Hb Matsue–Oki (α75 (EF4) Asp → Asn), together with heterozygosity for the sicilian (δβ)0-thal mutation. This finding highlights the necessity of deep molecular investigation of thalassemia in regions where thalassemia is abundant, and present highly heterogeneous population. 相似文献
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Given the rise of incidents of mass violence affecting college campuses, interventions for students are gravely needed, especially ones with broader accessibility and reach. This pilot study examined two online narrative writing interventions for undergraduates experiencing distress a year after exposure to a mass murder at their university. Thirty-nine students completed online narrative writing tasks across 4 days. Coping self-efficacy (CSE) and posttraumatic growth (PTG) were assessed. The intervention was feasible and acceptable, as demonstrated by high levels of completion at two follow-ups (97% and 87% respectively). Both groups had significant increases in CSE from baseline to postintervention. Implications and recommendations are discussed. 相似文献