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Alireza Behtoui 《British Journal of Sociology of Education》2019,40(3):340-356
Recent research demonstrates that, along with the family, the peer group and the school environment, extra-curricular activities are important contexts for young people’s educational and social development. This article is the result of a survey conducted with a sample of young people in their last year of compulsory school in Sweden and examines both who has access to the different types of extra-curricular activity and the consequences of their participation in the various programmes. As the results indicate, after controlling for respondents’ class and migrant background, their gender and their health, there are positive and significant associations between participation in certain types of activity (sporting, cultural and religious) on the one hand, and students’ school performance and educational expectations on the other. However, attendance at a less-organised activity (youth recreation centres or fritidsgård) shows a negative association with these outcomes. Furthermore, the results demonstrate that the gender, social class and migrant background of students affect their rate of participation in many of these activities. 相似文献
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The sociocultural orientation in general education, which has gradually leaked into second language teacher education, argues that teachers usually employ social relations, cultural artefacts, and theoretical concepts to mediate their thinking and practice. Against this background, the present study aimed to explore how three male Iranian English as a foreign language teachers have capitalised on the three sociocultural tools to mediate their development. The findings revealed that not all three mediational tools, though each influential in its own terms, have been available wholesale to the teachers and that different academic and teaching phases have yielded differential access to the tools. The authors indicate that during school as student, human mediation, particularly of apprenticeship, seems to be the dominant tool available for the teachers to mediate their development. Later on, in higher education institutes, although the human apprenticeship is still visible, cultural artefacts and scientific theories start to surface influencing the teachers’ learning and teaching trajectories. The implications for both teachers and teacher educators are discussed. 相似文献
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Alireza Nakhaee Mohammad Bokaeian Mohsen Saravani Ali Farhangi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2009,24(4):419-425
In traditional medicine, Eucalyptus globulus (eucalyptus) was used for the treatment of diabetes mellitus. Hyperglycemia in
diabetes has been associated with increased formation of reactive oxygen species (ROS) and oxidative damage to tissue compounds.
The aim of this study was to evaluate the effects of eucalyptus in the diet (20 g/Kg) and drinking water (2.5 g/L) on lipid
peroxidation, protein oxidation and antioxidant power in plasma and liver homogenate, as well as glycated-Hb (HbA1C) of blood in streptozotocin-induced diabetic rats for a period of 4 weeks. Diabetes induced in rats by a single intraperitoneal
injection of streptozotocin (STZ, 65 mg/Kg). At the end of the treatment period, the level of plasma glucose, plasma and liver
malondialdehyde (MDA, the main product of lipid peroxidation), protein carbonyl (PC, one of the protein oxidation products)
and HbA1C increased and ferric reducing antioxidant power (FRAP) decreased in diabetic rats compared to normal rats. Eucalyptus administration
for 4 weeks caused a significant decrease in the plasma glucose levels, plasma and liver MDA, PC and HbA1C, also a concomitant increase in the levels of FRAP in diabetic treated rats. In conclusion, the present study showed that
eucalyptus posses antioxidant activities. Eucalyptus probably restores antioxidant power, due to the improved hyperglycemia
in streptozotocin-induced diabetic rats. 相似文献
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Mehri Shahbazi Abdolhossein Farajpahlou Farideh Osareh Alireza Rahimi 《Library & information science research》2019,41(1):78-84
A credible scale based on the opinions of system users was developed to evaluate and assess data quality in automated library systems (ALS). Development and testing were carried out in two stages. In the first stage, 77 dimensions for data quality which had been previously identified through a systematic literature review were used to develop scale items. The first draft of the scale was then distributed among a target population of ALS experts to solicit their opinions on the scale and the items. In the second stage, a revised version of the scale was distributed among the main study population, which included end users of the target systems. This stage used factor analysis to determine the final draft of the scale, which consists of 4 factors and 62 items. The 4 factors were named after the qualities of their associated items: Data Content Quality, Data Organizational Quality, Data Presentation Quality, and Data Usage Quality. This scale can help system managers identify and resolve potential problems in the systems they manage and can also aid in evaluating the quality of data sources based on the opinions of end users. 相似文献
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Zahra Saffari Maryam Farahnak Zarabi Hasan Aryapour Alireza Foroumadi Ali Farhangi Soheil Ghassemi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2015,30(2):140-149
Chemotherapy drugs, used for prevention of uncontrolled cell proliferation in certain tissues as well as inducing apoptosis in tumor cells, are important candidates for treatment of cancer. The synthesized 2-amino-4H-chromene-3-carbonitrile derivatives effective on cancerous cells resistant to other drugs such as Paclitaxel were used due to their ability in induction of apoptosis. The growth inhibitory and inducing apoptosis activities were determined. In order to make it target-oriented, the best compound was conjugated with gold nanoparticles (NPs) by aspartic acid with chemical reduction method. Cytotoxicity effect of 2-amino-4H-chromene-3-carbonitrile derivatives against the T47D breast cancer cell line was determined by MTT assay. The synthesis of gold NPs was confirmed by transmission electron microscopy, UV–Vis and dynamic light scattering. To assess the effects of compounds on the process of apoptosis, staining methods with acridine orange–ethidium bromide and Hoechst staining by fluorescence microscopy and DNA fragmentation by the diphenylamine method were used. The synthesized compounds containing two NH2 groups on benzene rings, demonstrated more cytotoxicity effect. The effect of conjugation with gold NPs and the induction of apoptosis were studied with the best compound. The cytotoxicity effects of the synthesized 2-amino-4H-chromene-3-carbonitrile compounds were changed by replacement of NO2 group on thiol ring with different chemical groups on the benzene ring. Analyses of treated cell lines by conjugated and non-conjugated forms of compounds verified their ability in inducing apoptosis while conjugated form demonstrated higher apoptosis. 相似文献
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We analyze whether preferential attachment in scientific coauthorship networks is different for authors with different forms of centrality. Using a complete database for the scientific specialty of research about “steel structures,” we show that betweenness centrality of an existing node is a significantly better predictor of preferential attachment by new entrants than degree or closeness centrality. During the growth of a network, preferential attachment shifts from (local) degree centrality to betweenness centrality as a global measure. An interpretation is that supervisors of PhD projects and postdocs broker between new entrants and the already existing network, and thus become focal to preferential attachment. Because of this mediation, scholarly networks can be expected to develop differently from networks which are predicated on preferential attachment to nodes with high degree centrality. 相似文献
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Alireza Goudarzian Adel Khosravi Heidar Ali Raeisi 《Journal of The Franklin Institute》2019,356(15):8569-8594
This paper proposes a unified method to design an optimized type of the hysteresis modulation-based sliding mode current controller for non-minimum phase power converters in continuous conduction mode. The traditional sliding mode controlled converters have a slow transient voltage response at heavy loads, a large overshoot at light loads and during abrupt output resistance variations. To solve these problems, an optimized feedback control scheme is used according to the output resistance to adjust the coefficients of the controller. The basic idea of this controller is to suggest a new way for reduction of the sensitivity function amplitude of the closed loop system. The presented approach is developed for three basic DC/DC converters; i.e. boost, buck-boost and quadratic boost converters. Generally, the certain advantages of the suggested control approach are: (i) a fast transient response can be achieved in heavy load conditions, (ii) the voltage overshoot can be effectively reduced during load variations; (iii) the transient voltage overshoot can be eliminated in light load conditions; (iv) the closed loop control sensitivity can be reduced and therefore, the performance specification of a control system can be improved compared with the conventional sliding mode current control. To show the reliability of the suggested control scheme, simulations and experimental results for the derived systems are developed. Several conditions are performed to confirm the effectiveness of the proposed controller. 相似文献