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.     

The validity and reliability of a novel indoor player tracking system for use within wheelchair court sports

Abstract

The aim of the current study was to investigate the validity and reliability of a radio frequency-based system for accurately tracking athlete movement within wheelchair court sports. Four wheelchair-specific tests were devised to assess the system during (i) static measurements; (ii) incremental fixed speeds; (iii) peak speeds; and (iv) multidirectional movements. During each test, three sampling frequencies (4, 8 and 16 Hz) were compared to a criterion method for distance, mean and peak speeds. Absolute static error remained between 0.19 and 0.32 m across the session. Distance values (test (ii)) showed greatest relative error in 4 Hz tags (1.3%), with significantly lower errors seen in higher frequency tags (<1.0%). Relative peak speed errors of <2.0% (test (iii)) were revealed across all sampling frequencies in relation to the criterion (4.00 ± 0.09 m · sˉ¹). Results showed 8 and 16 Hz sampling frequencies displayed the closest-to-criterion values, whilst intra-tag reliability never exceeded 2.0% coefficient of variation (% CV) during peak speed detection. Minimal relative distance errors (<0.2%) were also seen across sampling frequencies (test (iv)). To conclude, the indoor tracking system is deemed an acceptable tool for tracking wheelchair court match play using a tag frequency of 8 or 16 Hz.     

EFFECTS OF TEACHER–STUDENT RELATIONSHIPS ON PEER HARASSMENT: A MULTILEVEL STUDY

Peer harassment is a major social problem affecting children and adolescents internationally. Much research has focused on student‐to‐student harassment from either an individual or a multilevel perspective. There is a paucity of multilevel research on students’ relationships with the classroom teacher. The purpose of this study was to use a socioecological perspective to examine the relationships between individual student‐level characteristics, problematic teacher–student relationships, and student‐reported peer harassment. A total of 1,864 children (50.7% female) aged 8 to 13 years (M = 9.82, SD = 1.24), nested in 27 schools (58.2% public) in Spain, participated in the study. Ninety‐four homeroom teachers reported on teacher–student relationships, and students completed self‐report measures related to peer harassment and teacher–student relationships. Multilevel models showed that relationships between students and teachers exerted a varying degree of influence on classroom levels of peer harassment. Specifically, student‐reported teacher support was associated with diminished student‐reported peer victimization, whereas direct and indirect student‐reported teacher‐to‐student aggression was associated with increased peer victimization. Additionally, student‐reported student‐to‐teacher aggression and teacher‐to‐student aggression were associated with increased student‐reported peer aggression. Teacher‐reported variables at the classroom level, however, contributed little to student‐reported outcomes. Results are discussed in the context of future research on relationships between teachers and students.     

Towards graduate employment: exploring student identity through a university-wide employability project

Students have expectations of their university education leading to graduate careers, with universities investing considerable resources in institution-wide initiatives designed to enhance opportunities for student work placements and work-related learning. However, there are large variations between courses and disciplines in student uptake of these opportunities, with limited evidence explaining why this might be the case. Recognising recent approaches which consider student identity in transitions, this study explored student attitudes to work-related learning across a range of subject disciplines. The first phase of the study used in-class surveys (N = 199) to focus on students’ self-identification and perceptions of employability initiatives. Follow-up interviews were conducted to further explore themes emerging in the survey data. The study found that, while some students drew on resources for identity work in their recognition of and approach to work-related learning, access was limited, and university resources were not always recognised or effective. The findings have implications for the design of effective graduate employability initiatives.     

Globalization and the freedom of knowledge

This article considers the transmission of knowledge in higher education. It takes the metaphor of the music industry that pre‐selects the music people can buy. The sales potential is the leading principle in the selection process. Often the small producer is excluded because his or her music is not of commercial interest. The end‐customer does not know what he or she is missing because he or she has never heard the music. It is to be feared that a similar market principle will also influence the selection of knowledge and affect the capacity of higher education institutions to freely generate and transmit new knowledge. The globalization of higher education risks homogenizing the cultural traditions of the non‐Western world through a process of Western cultural domination. On the other hand, the Internet, via open source software like LINUX, might serve to democratize higher education and allow greater grassroots input.     

Clapping with two hands: Bringing together local and outside knowledge for innovation in land husbandry in Tanzania and Ethiopia ‐ a comparative case study

Abstract

Promoting rural development in Africa involves learning to clap with two hands, that is to say, creating effective interaction between local knowledge and development initiatives, on the one hand, and the knowledge and initiatives of formal agricultural research and extension, on the other. Farmer innovators ‐men and women farmers who take their own initiative to change local agriculture ‐ are key allies in rural development, as shown by the experience of the ISWC programme in Africa. Focusing on Ethiopia and Tanzania, the authors describe how formal research and extension services are made aware of farmers’ innovative work and are encouraged to document the results, promote their spread, and support further development efforts by farmer innovators. A modified Participatory Technology Development (PTD) approach is thus emerging, which starts not with problem analysis but rather by linking up with local problem‐solving initiatives. While the learning process on this approach continues, dialogue has been initiated with policy‐makers with a view to incorporating the approach into regular government extension, research and training activities.     

From activity to gestures and scientific language

Abstract: Gestures may provide the long sought‐for bridge between science laboratory experiences and scientific discourse about abstract entities. In this article, we present our results of analyzing students' gestures and scientific discourse by supporting three assertions about the relationship between laboratory experiences, gestures, and scientific discourse: (1) gestures arise from the experiences in the phenomenal world, most frequently express scientific content before students master discourse, and allow students to construct complex explanations by lowering the cognitive load; (2) gestures provide a medium on which the development of scientific discourse can piggyback; and (3) gestures provide the material that “glues” layers of perceptually accessible entities and abstract concepts. Our work has important implications for laboratory experiments which students should attempt to explain while still in the lab rather than afterwards and away from the materials. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 38: 103–136, 2001     

Preschool teachers and classroom aides: Same context,similar perceptions of children's behaviors?

This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2^nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges.     

Activity of Prefrontal Cortex in Teachers and Students during Teaching of an Insight Problem

Metacognitive functions are important for both teachers and students to facilitate teaching and learning. The prefrontal cortex (PFC) plays a proven role in metacognition. As a pilot study, we evaluated the PFC activity of teachers and students using near‐infrared spectroscopy devices to explore the neural mechanism of PFC underlying metacognitive function during teaching and problem‐solving processes. In 14 student‐teacher pairs, participants in the teacher role gave hints via a tablet screen to facilitate solving of a tangram puzzle task by participants in the student role. The PFC activity of teachers increased after giving hints but not while planning hints. The PFC activity of students increased upon task solving after receiving hints. The PFC of teachers might play a metacognitive role in monitoring their own teaching results. The PFC activity of students might be related to the creativity process after gaining insights, as well as metacognitive process for monitoring their own behavior.     

A U‐Shaped Relation Between Sitting Ability and Upright Face Processing in Infants

A growing body of research indicates connections exist between action, perception, and cognition in infants. In this study, associated changes between sitting ability and upright face processing were tested in 111 infants. Using the visual habituation “switch” task (C. H. Cashon & L. B. Cohen, 2004; L. B. Cohen & C. H. Cashon, 2001), holistic processing of faces was assessed in same‐aged non‐ and near sitters (22–25 weeks) and same‐aged new and expert sitters (27–32 weeks). U‐shaped relation was found between sitting stage and holistic face processing such that only nonsitters and expert sitters processed faces holistically. It is posited that the results are due to a reorganization of the upright face‐processing system resulting from infants' learning to sit independently and trying to incorporate the meaning of upright faces.