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11.
Selection medium is important in sperm isolation for assisted reproductive technologies. Contrary to the naturally occurring human cervical mucus which has a high viscosity, most current practices for motility based sperm selection use a low viscosity medium. In this study, we used a microfluidic device to assess the effects of high viscosity media made with hyaluronic acid (HA) and methyl cellulose (MC) on bovine and human sperm motility and viability (sperm transferred directly from cryoprotectant). The microfluidic penetration test, viability, and motility were compared for sperm swimming in both HA and MC media with about 20cp viscosity (measured at 20 °C). Our resulted indicate that MC medium resulted in a significantly higher number of viable bovine sperm penetrating the medium as compared to HA. Furthermore, MC resulted in the selection of a sperm subpopulation with a 274% increase in sperm viability in comparison to the raw semen, while HA increased viability by only 133%. In addition to viability, bovine sperm motility parameters were significantly higher in the MC medium as compared with HA. Experiments with human sperm swimming in MC indicate that sperm swim slower and straighter at higher viscosities. In conclusion, the results indicate that in a micro-confined environment representative of the in vivo environment, MC is a preferred high viscosity medium to ensure the highest concentration of motile and viable sperm. 相似文献
12.
Marion Dresner Corinne Handelman Steven Braun Gretchen Rollwagen-Bollens 《Environmental Education Research》2015,21(7):991-1010
We conducted surveys of adults participating in municipally sponsored volunteer events in the Portland, OR metropolitan area in order to understand the range of attitudes and behaviors associated with volunteer work. We sampled 172 individuals in 18 events from February to June 2012. Principal components and factor analyses of survey responses identified three groups based on annual frequency of participation in stewardship events: first-time volunteers, mid-level volunteers (3–10 events per year), and frequent volunteers (>10 events per year). Our analyses revealed three main factors that explained the variation in survey response for the three volunteer groups: environmental identity, private pro-environmental behavior, and civic engagement. All three factors were positively correlated with frequency of participation in stewardship events, with the most frequent volunteers indicating the highest degree of attention to environmental issues, environmental identity, and self-reported pro-environmental behaviors. Frequent volunteers were more likely to feel personally attached to their local environment, believe that their efforts help solve environmental problems, and enjoy being part of community efforts. These results suggest that stewardship activities provide opportunities for volunteers to interact with others while working collectively toward restoring and maintaining parks, which may contribute to more resilient communities. 相似文献
13.
Higher Education - This paper offers a reconceptualisation of international students’ transitions into and through UK higher education. We present two case studies of students which explore... 相似文献
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Fátima Viteri Geraldine Clarebout Marion Crauwels 《Environmental Education Research》2014,20(2):228-247
This study examined recall (Rcl) differences of high, average and low achieving fifth-grade elementary students (72) for an environmental education video with supporting pedagogical materials. In addition, it assessed the motivational level of all students. Recall assessment was carried out one-week and twenty-weeks after intervention. Main findings suggest comparative Rcl results for all achievers and high motivation for the designed video and pedagogical materials. Implications for future research and for an integrative materials’ design approach are presented. 相似文献
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This exploratory study investigates gender-specific differences in the challenges of the doctoral experience through the observations of a counsellor working with doctoral students. The article first contextualises the study within the literature investigating doctoral attrition and gender equity, showing that identity transformation over the doctorate is problematic in particular aspects for women. We confirm that cultural expectations regarding women passivity, family nurturance and (at least symbolic) subordination to male authority can cause tensions between women's social relationships and academic performance which values assertiveness, clear communication and confident management of power relationships. We identify various conflicts between the female roles of the social sphere and the academic arena that problematise the identity transition of the doctorate from student to independent researcher. 相似文献
18.
Marion Hersh Stella Mouroutsou 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(6):3329-3344
The paper uses data from a 15-country study to discuss the factors which affect the use of information and communication technologies (ICT) and learning technologies by disabled people and consequently their access to education. Significant differences were found both between and within countries: income and language were the main factors affecting availability. Thus, the greatest availability was in the higher income English-speaking countries and the richer European countries. The main barriers to technology use included cost, lack of funding and lack of information. A particular disparity in technology access was found between the English-speaking European population and Aboriginal speakers of indigenous languages in Australia, with considerably greater access by the former than the latter group. A number of recommendations are presented to increase access to learning and assistive technologies by disabled people. They include encouragement for developers to produce free of charge (minority language) technologies, research on more effective provision of technologies and personal assistance, assistive technology centres in all learning institutions, simple funding mechanisms and a fund to support technology provision in poorer countries. 相似文献
19.
Marian Marion 《Early Childhood Education Journal》1993,20(3):4-8
Julia, Darryl, and Shantal are all learning very different ways to deal with angry feelings.Unpleasant feelings are like weeds. They don't go away when we ignore them; they grow wild and take over. (Beattie, 144).Marian Marion is Professor of Human Development and Early Childhood Education, University of Wisconsin-Stout, Menomonie, WI. 相似文献
20.
Mona Whitley Howard Marion G. Sobol 《Decision Sciences Journal of Innovative Education》2004,2(1):27-44
In today's era of global competition, organizations must manage their functions and activities in a manner such that they are responsive to customers' needs and can provide excellence in service to the customer while also being efficient and cost conscious. These issues are extremely common in corporate organizations, but such concerns are equally relevant in service industries, including institutions of higher education. This study is conducted at a private, undergraduate institution of higher education. We utilize focus group evaluation and conjoint analysis combined with economic analysis in the form of a newly designed preferred utility economic cost diagram to pick the ideal services that should be provided to enrolled students at the institution. The package of ideal services accounts for preferred utility expressed by students and a new methodology (preferred utility function) to balance these against financial considerations to optimize services and financial gains for a college adult education program. This combination of focus groups and mathematical techniques can be easily employed by educational institutes. 相似文献