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Swastika S. Bithi William S. Wang Meng Sun Jerzy Blawzdziewicz Siva A. Vanapalli 《Biomicrofluidics》2014,8(3)
Multiwell plate and pipette systems have revolutionized modern biological analysis; however, they
have disadvantages because testing in the submicroliter range is challenging, and increasing the
number of samples is expensive. We propose a new microfluidic methodology that delivers the
functionality of multiwell plates and pipettes at the nanoliter scale by utilizing drop coalescence
and confinement-guided breakup in microfluidic parking networks (MPNs). Highly monodisperse arrays
of drops obtained using a hydrodynamic self-rectification process are parked at prescribed locations
in the device, and our method allows subsequent drop manipulations such as fine-gradation dilutions,
reactant addition, and fluid replacement while retaining microparticles contained in the sample. Our
devices operate in a quasistatic regime where drop shapes are determined primarily by the channel
geometry. Thus, the behavior of parked drops is insensitive to flow conditions. This insensitivity
enables highly parallelized manipulation of drop arrays of different composition, without a need for
fine-tuning the flow conditions and other system parameters. We also find that drop coalescence can
be switched off above a critical capillary number, enabling individual addressability of drops in
complex MPNs. The platform demonstrated here is a promising candidate for conducting multistep
biological assays in a highly multiplexed manner, using thousands of submicroliter samples. 相似文献
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Cieszczyk P Ostanek M Leońska-Duniec A Sawczuk M Maciejewska A Eider J Ficek K Sygit K Kotarska K 《Journal of sports sciences》2012,30(1):31-35
The aims of this study were to determine the distribution of the AMPD1 genotype among groups of high-level Polish power-oriented athletes, and to investigate potential associations between genetic polymorphism in exon 2 of the AMPD1 gene and power-oriented athlete status. Altogether, 158 male Polish power-oriented athletes were genotyped by PCR-RFLP. The genetic control group comprised 160 unrelated male volunteers. We observed significant differences in genotype distribution when all 158 athletes (89.25% CC, 10.75% CT, 0.00% TT; P = 0.0025) were compared with controls (75.00% CC, 23.75% CT, 1.25% TT). A significant deficiency of the T allele was noted in all subgroups (short-distance runners: 5.21%, P = 0.032; short-distance swimmers: 5.56%, P = 0.031; weightlifters: 5.36%, P = 0.024) compared with controls (13.13%), while this trend was even stronger when the frequency of the T allele was compared between controls and all 158 athletes (5.38%, P = 0.0007). Our results indicate a lower frequency of the AMPD1 exon 2 T34 allele in elite Polish power-oriented athletes. Our data suggest that the C allele may help athletes to attain elite status in power-oriented sports. 相似文献
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Jerzy Cieślik 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1982,28(4):457-467
Two main questions are discussed. First, how might transnational corporations contribute to various forms of education in developing countries? Secondly, what measures should states take in education to help them get better advantage from the transnational corporations? Adopting a pragmatic approach, the paper points out that the most important form of education is often the most overlooked, namely, on-the-job training in a range of occupations from low skilled to top management. Although this is indeed supplemented by in-service training programmes, the latter are not always on offer. In general, transnational corporations are interested in education in their host countries only insofar as it affects their own operations. For their part, host country governments have a difficult task. On the one hand they need to educate their young people to be able to take advantage of the technology and expertise made available by the transnational corporations. On the other hand, they need to give them an education which will help them to preserve their culture, despite absorbing the technology and thereby also the culture of foreign firms. More particularly, host countries seem to lack the specialized training, which is necessary for dealing effectively and advantageously with the transnational corporations. In a final note, the paper considers what might happen if a ‘real’ NIEO were introduced. 相似文献
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Katarzyna Polak Jerzy Stanisław Gielecki Anna Żurada 《Anatomical sciences education》2022,15(6):1060-1073
The affordances of technology-based assessments, like the objectively structured practical examination, have become an integral part of gross anatomy courses. The Department of Anatomy Faculty of Medicine at the University of Warmia and Mazury developed and introduced an application for tablet devices which has been implemented in student examinations and assessments, called the tablet-assisted objective structured spotter practical examination. It was created to simplify the educational process and to build a rich learning environment, facilitating deep learning for students through examination and feedback data. The method consists of cadaver stations with traditional corresponding pin spotters in an expanded tablet application. It not only provides instant feedback on various observations of teaching–learning skills but has also positively affected the entire process of education. The method provides an unbiased evaluation of knowledge and understanding of the anatomy course, ensuring objectivity and standardization. The current study was performed on a total of 608 first-year medical students in Polish and English divisions and focused on the observed advantages since the new method was introduced. Outcomes indicate that after the implementation of the method for both the Polish and English divisions' first-year medical students, the mean score of examinations significantly increased compared to other teaching–learning methods. The study highlights that students were excited about the implementation of the new method and identified its many benefits. It is recognized that technological development and the digital environment offer a range of opportunities and added value versus traditional assessment activities, methods, and processes. 相似文献
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ABSTRACTGlass is often seen as a relatively stable material, unaffected by changes in environmental conditions, but recent studies indicate otherwise. Research on the atmospheric deterioration of glass has consistently shown a strong correlation between climate, especially relative humidity (RH), and the rate of deterioration. New studies by the authors have shown that even stable compositions are at risk, when the glasses are exposed to continuous broad fluctuations in RH and temperature. Letting standards slip for the long-term storage of glass can be devastating, eventually leading to irreversible damage that in the final stages can result in the complete destruction of an object. Current research and monitoring of collections at the Corning Museum of Glass indicates that the RH should be within the range of 40–50%. For already crizzled glasses, a tighter control to 40–42% is recommended. Analysis of compositions of already crizzled glasses is ongoing, and hopefully will lead to the identification of at least some groups of glasses that are more at risk. This will help in providing future environmental recommendations for identifiable compositions, selected glass types, or known manufacturers. 相似文献
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Wolanczyk-Medrala A Dor A Szczepaniak W Tomkowicz T Liebhart J Panaszek B Medrala W 《Journal of sports sciences》2008,26(13):1467-1471
A few studies have reported data on the prevalence of exercise-induced bronchospasm in high school and university athletes. Recently published data suggest that exercise-induced bronchospasm may affect up to 39% of American university athletes. To date, no data describing this pathology in athletes from Central Europe have been published. The aim of the present study was to establish the prevalence of exercise-induced bronchospasm in pupils attending sports mastership classes in secondary school as well as students of the University of Physical Education in Wroclaw. The participants were 77 athletes (30 women and 47 men) aged 16-27 years (mean 17.3 years). Only one athlete (1.29%) diagnosed with atopic asthma before testing experienced a fall in forced expiratory volume in one second (12.9% FEV(1)) compared with baseline, which showed that the exercise test result was positive. From a clinical point of view, the ventilation disturbance was asymptomatic. In the other participants, there were slight but statistically significant rises in FEV(1) (P < 0.02). The results of our study indicate a very low prevalence of exercise-induced bronchospasm in the population of athletes examined. 相似文献
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Erin L. Ratliff Kara L. Kerr Masaya Misaki Kelly T. Cosgrove Andrew J. Moore Danielle C. DeVille Jennifer S. Silk Deanna M. Barch Susan F. Tapert W. Kyle Simmons Jerzy Bodurka Amanda Sheffield Morris 《Child development》2021,92(6):e1361-e1376
The parent–adolescent relationship is important for adolescents’ emotion regulation (ER), yet little is known regarding the neural patterns of dyadic ER that occur during parent–adolescent interactions. A novel measure that can be used to examine such patterns is cross-brain connectivity (CBC)—concurrent and time-lagged connectivity between two individuals’ brain regions. This study sought to provide evidence of CBC and explore associations between CBC, parenting, and adolescent internalizing symptoms. Thirty-five adolescents (mean age = 15 years, 69% female, 72% Non-Hispanic White, 17% Black, 11% Hispanic or Latino) and one biological parent (94% female) completed an fMRI hyperscanning conflict discussion task. Results revealed CBC between emotion-related brain regions. Exploratory analyses indicated CBC is associated with parenting and adolescent depressive symptoms. 相似文献