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1.
While there is a growing body of work that examines disciplinary identity development, unlike qualitative work in this area, quantitative research has not fully incorporated the importance of different contexts, nor has it uniquely focused on underrepresented groups (in this case, women in physics). This study examines how the constructs posited by prior work as important for physics identity, as well as an additional theorized construct, may interrelate and affect female students' physics identity differently depending on the context. Context in this study refers to two different experiential levels in college. The constructs examined include performance/competence, recognition, and interest, as well as sense of belonging. In particular, we used structural equation modeling to examine the effect that these constructs have on the physics identity of two groups of female physics undergraduates: first year students and senior year students. The results reveal that the relationship of the theorized constructs with physics identity vary between the two groups as well as compared to prior research with broad college student populations (not just physics majors). Unlike broad college student populations, for our sample of female physics undergraduates, interest did not have a direct effect on physics identity while sense of belonging was significant only for senior year students. These results exemplify the importance of examining context or different types of student experiences when studying disciplinary identity development rather than generalizing previous frameworks to all contexts.  相似文献   
2.
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate (50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients. Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results, it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus.  相似文献   
3.
Education and Information Technologies - Education accountability and its building components has been the focal point and yet a convoluted issue. The current study aims to give a comprehensive...  相似文献   
4.
In recent years, the advent of low-cost digital and mobile devices has led to a strong expansion of social interventions, including those that try to improve student learning and literacy outcomes. Many of these are focused on improving reading in low-income countries, and particularly among the most disadvantaged. Some of these early efforts have been called successful, but little credible evidence exists for those claims. Drawing on a robust sample of projects in the domain of mobiles for literacy, this article introduces a design solution framework that combines intervention purposes with devices, end users, and local contexts. In combination with a suggested set of purpose-driven methods for monitoring and evaluation, this new framework provides useful parameters for measuring effectiveness in the domain of mobiles for literacy.  相似文献   
5.
The changes in journal internationality in mainstream science were examined using 1,398 journals and 2,557,229 papers during 1991–2014. The authors’ country of affiliation in journals’ papers and references of multinational and national publishers were analysed. The results showed that journals’ papers and references have become more globalized over time. On average, older journals are more international than the newer ones. Although multinational publishers publish more international journals than the national ones do, journals from national publishers have internationalized faster than those from multinationals. The difference between these two groups of publishers is much greater in authoring compared to referencing. For both groups of publishers, the most changes in journal internationality occurred between the fourth and sixth year of indexing in Web of Science. Journals and papers in Humanities journals have the highest rate of increase of internationality although Natural Sciences and Engineering and Technology have the most international papers. Agricultural Sciences has the least international papers; however, these papers cite a wider range of countries’ papers compared to other fields. Journals in Medical and Health Sciences, Natural Sciences, and Agricultural Sciences have the most international references.  相似文献   
6.
Corporate venturing and value creation: A review and proposed framework   总被引:1,自引:0,他引:1  
Over the past decade, companies worldwide have used corporate venturing (CV) as a means of revitalizing their operations, building new capabilities, and achieving strategic renewal, creating value for shareholders. Business interest in CV has stimulated academic interest in the topic, resulting in a rapidly growing but fragmented body of literature. Despite the growing international scholarly interest in CV, researchers have devoted little effort to integrating prior findings in a cumulative fashion. As a result, studies do not build upon one another, making it difficult to gauge the progress being made in addressing the fundamental research questions related to CV. In this paper, we examine the literature on CV seeking to synthesize, integrate and link its key findings. To do so, we analyze this literature over the past decade to identify its major themes and research findings setting the stage for greater coherence in future research on CV. We give special attention to the challenges and rewards of theory building in future CV research. Our review clearly shows that CV is an area of scholarly inquiry that has important implications for managerial practice.  相似文献   
7.
The need for cell and particle sorting in human health care and biotechnology applications is undeniable. Inertial microfluidics has proven to be an effective cell and particle sorting technology in many of these applications. Still, only a limited understanding of the underlying physics of particle migration is currently available due to the complex inertial and impact forces arising from particle–particle and particle–wall interactions. Thus, even though it would likely enable significant advances in the field, very few studies have tried to simulate particle-laden flows in inertial microfluidic devices. To address this, this study proposes new codes (solved in OpenFOAM software) that capture all the salient inertial forces, including the four-way coupling between the conveying fluid and the suspended particles traveling a spiral microchannel. Additionally, these simulations are relatively (computationally) inexpensive since the arbitrary Lagrangian–Eulerian formulation allows the fluid elements to be much larger than the particles. In this study, simulations were conducted for two different spiral microchannel cross sections (e.g., rectangular and trapezoidal) for comparison against previously published experimental results. The results indicate good agreement with experiments in terms of (monodisperse) particle focusing positions, and the codes can readily be extended to simulate two different particle types. This new numerical approach is significant because it opens the door to rapid geometric and flow rate optimization in order to improve the efficiency and purity of cell and particle sorting in biotechnology applications.  相似文献   
8.
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   
9.
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   
10.
Conduct disorder (CD) is one of the most common childhood psychiatric disorders. Some research has focused on reducing conduct difficulties through parent training programmes. However, there has been limited research focusing on early intervention services that deal with emotional and/or conduct problems in a community setting. The aim of this study was to evaluate the overall effectiveness of the Scallywags service, a multi‐component, early intervention scheme, offering support in the educational and home setting. A total of 411 children, aged 3 to 7 years, was included in this study. Two behaviour inventories were used as the outcome measures. Parents and teachers completed these pre, post, and six months after the intervention. Results demonstrate significant decreases in child conduct problems after the six months intervention, with this change maintained six months later. This study adds to growing research illustrating the importance of multi‐component, early intervention schemes to reduce child conduct problems.  相似文献   
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