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31.
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   
32.
Abstract

This 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   
33.
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   
34.
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   
35.
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   
36.
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   
37.
This article reports on a pilot study of the Integrated Literacy Study Group, a digitally delivered professional learning intervention to prepare elementary school teachers to provide evidence-based reading instruction and behavioral strategies to students with or are at risk for emotional and behavioral disorders. Using broadcast methods, we recruited 72 teachers across five states in the western United States to participate in the randomized controlled trial. Intervention teachers, relative to controls, made significant gains in self-efficacy and use of the reading and behavioral strategies learned in the professional learning program. Students with or at risk of emotional and behavioral disorders served by participating teachers made significant improvements in academic competence and engagement. Teacher professional learning can improve teacher knowledge of evidence-based reading and behavioral strategies for students with (or at risk for) emotional and behavioral disorders, teacher self-efficacy, and teacher practice, with positive impacts on student early literacy and academic competence.  相似文献   
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