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71.
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
72.
73.
Bret G. Range Susan Scherz Carleton R. Holt Suzanne Young 《Educational Assessment, Evaluation and Accountability》2011,23(3):243-265
The intent of this study was to assess the perceptions and actions of Wyoming principals concerning their role in supervising
and evaluating teachers. A survey was sent to all 286 principals in the state of Wyoming, of which, 143 returned surveys,
a response rate of 50%. Findings suggested that principals utilized supervisory behaviors more often than evaluative behaviors.
Elementary principals perceived their evaluative practices as significantly more prevalent than secondary principals. Furthermore,
principals indicated that their greatest frustrations in supervising teachers were time, the evaluation instrument, and teachers’
unwillingness to change. Additionally, findings suggested that Wyoming principals utilized classroom walkthroughs because
they provided a snapshot of teaching and provided a medium for providing feedback. In regards to developmental supervision,
principals indicated that novice teachers received much more supervision than veteran teachers. However, their reported use
of differentiated supervision only applied to teacher autonomy concerning professional development goals. Principals reported
that teachers had little input concerning the methods by which they were supervised. Finally, a majority of the Wyoming principals
felt that improvement plans were effective at changing mediocre teaching behaviors, but 40% were speculative that such plans
truly remediated poor teachers. 相似文献
74.
Nuala Gregory 《Educational Philosophy and Theory》2015,47(6):563-578
AbstractThis article brings together and compares my own artistic practice of drawing/painting and the eighteenth-century novel Tristram Shandy. In both cases, there is a free play of lines, textual or graphic, which sets ‘all things out of rule’. A whole typology of lines is woven throughout Sterne’s text and reappears, alter-inscribed, in the artworks. The article presents an account of these lines: rectilinear, hylomorphic, fractal and nomadic, as well as the line of incision (or the cut). Each is explored as a specific mode of line with differing effects. To follow these lines is to enter a world of material expressivity, to be exposed to an ontology of becoming and change, of flows and transformations, that overturns the traditional ontology of being and stable identity. Sterne’s use of wild digression, doodles and graphisms, establishes certain proximity between writing and drawing. Both may be seen as types of ‘figured metaphysics’ and as ways of bringing something new into the world. The article concludes with some philosophical observations on the strange event of drawing a line, with reference to the work of Heidegger and Deleuze and Guattari. 相似文献
75.
The need to address the substantial inequities that exist between Indigenous and non-Indigenous Australians in higher education is widely recognised. Those factors that affect the performance of Indigenous students in tertiary education have been reasonably well documented across different institutions, disciplines, and programme levels but there has, to date, been less consideration of the processes by which Indigenous students either persist or desist in higher education. This paper aims to present a conceptual understanding of academic persistence that can inform the delivery of tailored academic support interventions to Indigenous students who are at high risk of leaving higher education. 相似文献
76.
77.
Dorie J. Gilbert Mary Lehman Held Janet L. Ellzey William T. Bailey Laurie B. Young 《European Journal of Engineering Education》2015,40(3):256-266
This article reviews the literature on challenges faced by engineering faculty in educating their students on community-engaged, sustainable technical solutions in developing countries. We review a number of approaches to increasing teaching modules on social and community components of international development education, from adding capstone courses and educational track seminars to integrating content from other disciplines, particularly the social sciences. After summarising recent pedagogical strategies to increase content on community-focused development, we present a case study of how one engineering programme incorporates social work students and faculty to infuse strategies for community engagement in designing and implementing student-led global engineering development projects. We outline how this interdisciplinary pedagogical approach teaches students from the two disciplines to work together in addressing power balances, economic and social issues and overall sustainability of international development projects. 相似文献
78.
The effect of technology-enhanced learning (TEL) strategies in higher education has arguably been transformative despite the not-insignificant barriers existing in this context. Throughout the discourse very little attention has been paid to those primarily responsible for this implementation—academic teaching staff. This paper aims to highlight the impact of academic workload allocations, an often silent barrier to the uptake of TEL strategies in higher education. We will discuss the effects of academic identity and culture, preferential time allocation to associative activities, academic technological capacity, university policies and workload and funding models on the uptake, and implementation on TEL in higher education. Our aim is to highlight the risks to staff, students and institutions should these concerns not be addressed and to propose a model for utilisation by all staff responsible for implementing flexible workload models supportive of further implementation of TEL strategies across the sector. 相似文献
79.
Gregory T. Hatchett 《Journal of College Counseling》2015,18(1):37-48
This study describes the development of the Preferences for College Counseling Inventory (PCCI). In addition to providing data about college students' preferences for the logistics of counseling and the demographic/professional background of a potential therapist, the PCCI also provides numerical scores on 3 scales (Therapist Expertise, Therapist Warmth, and Therapist Directiveness) that measure preferences for therapist dispositions and 2 scales (Task‐Oriented Activities and Experiential/Insight‐Oriented Activities) that measure preferences for counseling activities. 相似文献
80.
Kenneth A. Dodge Yu Bai Jennifer Godwin Jennifer E. Lansford John E. Bates Gregory S. Pettit Damon Jones 《Child development》2022,93(4):e357-e378
The hypothesis was tested that some children develop a defensive mindset that subsumes individual social information processing (SIP) steps, grows from early experiences, and guides long-term outcomes. In Study 1 (Fast Track [FT]), 463 age-5 children (45% girls; 43% Black) were first assessed in 1991 and followed through age 32 (83% retention). In Study 2 (Child Development Project [CDP]), 585 age-5 children (48% girls, 17% Black) were first assessed in 1987 and followed through age 34 (78% retention). In both studies, measures were collected of early adverse experiences, defensive mindset and SIP, and adult outcomes. Across both studies, a robust latent construct of school-age defensive mindset was validated empirically (comparative fit index = .99 in each study) and found to mediate the impact of early child abuse (38% in FT and 29% in CDP of total effect) and peer social rejection (14% in FT and 7% in CDP of total effect) on adult incarceration. 相似文献