Sub-nanomolar detection of thrombin activity on a microfluidic chip

Bioluminescence resonance energy transfer (BRET) is a form of Förster resonance energy transfer. BRET has been shown to support lower limits of detection than fluorescence resonance energy transfer (FRET) but, unlike FRET, has not been widely implemented on microfluidic devices for bioanalytical sensing. We recently reported a microscope-based microfluidic system for BRET-based biosensing, using a hybrid, high quantum-efficiency, form of BRET chemistry. This paper reports the first optical fiber-based system for BRET detection on a microfluidic chip, capable of quantifying photon emissions from the low quantum-efficiency BRET² system. We investigated the effects of varying core diameter and numerical aperture of optical fibers, as well as varying microfluidic channel design and measurement conditions. We optimized the set-up in order to maximize photon counts and minimize the response time. The optimized conditions supported measurement of thrombin activity, with a limit of detection of 20 pM, which is lower than the microscope-based system and more than 20 times lower than concentrations reported to occur in plasma clots.     

Persistent Focal Behavior and Physical Activity Performance

This article examines the proclivity and performance attributes of focal students across time and activities using data from 9,345 students. Three systematic focal behavior partitions are examined: Across activities, across time, and across activities and time. A student’s performance is focal if it ends in 0 or 5 for push-ups and 0 for curl-ups. Chi-square tests confirm that individual focal outcomes and systematic focal outcomes occur more frequently than random processes would suggest. In each instance, the only cell that is less populated than random processes would suggest is the one that exhibits no systematic focal behavior and the cell that exhibits the greatest deviation from expected is the full focal cell. Focal students outperform their peers on three activities at two assessments. Students with two-systematically focal outcomes have superior performance to students with no systematic focal outcomes but inferior performance to those with three or four focal outcomes.     

Negotiating the Research Imperative: The Views of UK Academics on their Career Opportunities

This article provides an analysis of the views of UK academic staff, given in response to a postal survey, on their opportunities for career progression through job appointments and promotion. The article investigates academics'opinions on the prominence of research, teaching and administration in determining career progression, and looks in particular at the effect of the Research Assessment Exercise on careers. There is consensus that the emphasis on research in determining careers has gone too far. The article considers the reasons for this, and looks at policy implications of this finding.     

Neuroimaging Studies of Reading Development and Reading Disability

Converging evidence from a number of neuroimaging studies, including our own, suggest that fluent word identification in reading is related to the functional integrity of two left hemisphere posterior systems: a temporo-parietal system and a ventral occipito-temporal system. These posterior systems are functionally disrupted in developmental dyslexia. Reading disabled, relative to nonimpaired, readers demonstrate heightened reliance on both inferior frontal and right hemisphere posterior regions, presumably in compensation for the LH posterior difficulties. We propose a neurobiological account suggesting that for normally developing readers the temporo-parietal system predominates at first, and is associated with aspects of processing critical in learning to integrate orthography with phonological and lexical-semantic features of printed words. The occipito-temporal system, by contrast, constitutes a fast, late-developing, word-identification system that underlies fluent word recognition in skilled readers.     

Learning through work: Exploring instances of relational interdependencies

This paper provides an account of the inter-psychological processes that constitute learning through work. It does this by drawing on deliberations about the relative contributions of the immediate social world (i.e., workplace setting) that individuals encounter and the personal premises for individuals’ learning. This account is realised through analyses of workers’ experiences of working and learning in both large and small enterprises. Together, these premises and their contributions are used to elaborate how learning through work proceeds as a process of relational interdependence between the affordance of the workplace and the engagement of workers. This relational process is evident in work of different kinds, from the labours of coalminers through to the entrepreneurial activities of small business operators. Instances of learning through work are elaborated through studies that identify how workplaces’ affordances—those that invite workers in particular ways to participate, access support and reward—are generated and projected. These contributions to engaging in and learning through work can be conceptualised as the immediate social contribution or experience that is shaped by cultural and situational factors and the social legacies that shape how individuals construe, engage in, and learn through those practices. It concludes by discussing issues related to both the inter-psychological process and outcomes (e.g., inter-subjectivity) arising from learning through work.