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91.
Christopher R. Phaneuf Nikita Pak D. Curtis Saunders Gregory L. Holst Joav Birjiniuk Nikita Nagpal Stephen Culpepper Emily Popler Andi L. Shane Robert Jerris Craig R. Forest 《Biomicrofluidics》2015,9(4)
Amplification of multiple unique genetic targets using the polymerase chain reaction (PCR) is commonly required in molecular biology laboratories. Such reactions are typically performed either serially or by multiplex PCR. Serial reactions are time consuming, and multiplex PCR, while powerful and widely used, can be prone to amplification bias, PCR drift, and primer-primer interactions. We present a new thermocycling method, termed thermal multiplexing, in which a single heat source is uniformly distributed and selectively modulated for independent temperature control of an array of PCR reactions. Thermal multiplexing allows amplification of multiple targets simultaneously—each reaction segregated and performed at optimal conditions. We demonstrate the method using a microfluidic system consisting of an infrared laser thermocycler, a polymer microchip featuring 1 μl, oil-encapsulated reactions, and closed-loop pulse-width modulation control. Heat transfer modeling is used to characterize thermal performance limitations of the system. We validate the model and perform two reactions simultaneously with widely varying annealing temperatures (48 °C and 68 °C), demonstrating excellent amplification. In addition, to demonstrate microfluidic infrared PCR using clinical specimens, we successfully amplified and detected both influenza A and B from human nasopharyngeal swabs. Thermal multiplexing is scalable and applicable to challenges such as pathogen detection where patients presenting non-specific symptoms need to be efficiently screened across a viral or bacterial panel. 相似文献
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This paper asks whether the institutional hierarchies defined by ‘golden triangle’, other Russell Group, other pre-1992 and post-1992 universities in England, and by ancient, old and new universities in Scotland, have become weaker since the 1990s. Using indicators constructed from Universities and Colleges Admissions Service data for 1996–2010, the article finds a stable hierarchical relationship among the sectors within each country, with some indicators showing a slight widening of status differences between sectors towards the end of the period. The main exception was a slight ‘upgrading’ of new (post-1992) universities in Scotland early in the period. There was little change in the association of institutional sector with social class, but in England the association with private secondary schools became slightly stronger and the association with ethnicity weakened. 相似文献
95.
Mindfulness‐based awareness and compassion were examined as predictors of empathy and anxiety among 152 master's‐level counseling interns. Results of hierarchical multiple regression analysis supported that awareness and compassion differentially contributed to explaining the variance in counselor empathy and anxiety. Implications for counselor education are discussed. 相似文献
96.
Wietse van der Linden Anouke Bakx Anje Ros Douwe Beijaard Linda van den Bergh 《师资教育杂志》2015,41(1):4-18
This study reports on the development of second-year student teachers’ knowledge of research, and the changes in their beliefs and attitude regarding research during an introductory course at an institute for primary teacher education. Questionnaires and concept maps were administered before and after the course. The results showed that student teachers’ knowledge about research grew during the introductory course and that their positive beliefs about research became more positive, while their negative beliefs about research decreased. A positive change was found concerning the attractiveness of research to student teachers. Furthermore, student teachers’ self-efficacy regarding research appeared related to their beliefs and attitude: the more the student teachers were convinced of their abilities to conduct and use the results of research after the course, the more positive their beliefs and their attitude regarding research were. This study provides guidelines for institutes for teacher education on integrating research activities into their curricula, so that their student teachers develop research knowledge and positive beliefs and attitudes towards research. 相似文献
97.
Linda Gilmore Monica Cuskelly Melissa Browning 《International Journal of Disability, Development & Education》2015,62(3):265-275
The main purpose of the current study was to provide empirical evidence to support or refute assumptions of phenotypic deficits in motivation for children with Down syndrome (DS). Children with moderate intellectual disability (MID) associated with etiologies other than DS were recruited in an extension of a previous study that involved children with DS and typically developing children. The participants were 29 children with MID and 33 children with DS who were matched on mental age to 33 typically developing children, aged 3–8 years. Mastery motivation was assessed on task measures of curiosity, preference for challenge and persistence, as well as parental reports. There were no significant group differences on the mastery motivation tasks. Parental ratings of mastery motivation differed, with typically developing children generally being rated more highly than each of the disability groups. The view that motivational deficits are part of the DS behavioural phenotype was not supported. 相似文献
98.
Foster Colin Woodhead Simon Barton Craig Clark-Wilson Alison 《Educational Studies in Mathematics》2022,109(3):491-521
Educational Studies in Mathematics - In this paper, we analyse a large, opportunistic dataset of responses (N = 219,826) to online, diagnostic multiple-choice mathematics questions, provided by... 相似文献
99.
George Kari L. Sax Linda J. Wofford Annie M. Sundar Sarayu 《Research in higher education》2022,63(5):871-898
Research in Higher Education - Computing career opportunities are increasing across all sectors of the U.S. economy, yet there remains a serious shortage of college graduates to fill these jobs.... 相似文献
100.
Öberg Gunilla Campbell Alice Fox Joanne Graves Marcia Ivanochko Tara Matsuchi Linda Mouat Isobel Welsh Ashley 《Science & Education》2022,31(3):787-817
Science & Education - The widespread misperception of science as a deliverer of irrefutable facts, rather than a deliberative process, is undermining public trust in science. Science education... 相似文献