Microfluidic electromanipulation with capacitive detection for the mechanical analysis of cells

The mechanical behavior of cells offers insight into many aspects of their properties. We propose an approach to the mechanical analysis of cells that uses a combination of electromanipulation for stimulus and capacitance for sensing. To demonstrate this approach, polystyrene spheres and yeast cells flowing in a 25 μm×100 μm microfluidic channel were detected by a perpendicular pair of gold thin film electrodes in the channel, spaced 25 μm apart. The presence of cells was detected by capacitance changes between the gold electrodes. The capacitance sensor was a resonant coaxial radio frequency cavity (2.3 GHz) coupled to the electrodes. The presence of yeast cells (Saccharomyces cerevisiae) and polystyrene spheres resulted in capacitance changes of approximately 10 and 100 attoFarad (aF), respectively, with an achieved capacitance resolution of less than 2 aF in a 30 Hz bandwidth. The resolution is better than previously reported in the literature, and the capacitance changes are in agreement with values estimated by finite element simulations. Yeast cells were trapped using dielectrophoretic forces by applying a 3 V signal at 1 MHz between the electrodes. After trapping, the cells were displaced using amplitude and frequency modulated voltages to produce modulated dielectrophoretic forces. Repetitive displacement and relaxation of these cells was observed using both capacitance and video microscopy.     

The impact of congruence between perceived and preferred leadership on satisfaction among college student-athletes in Singapore

Chelladurai developed the Multidimensional Model of Leadership, which was designed to be situation-specific to examine leadership behaviour and effectiveness in sporting contexts. Applying Chelladurai's concept to the Singapore sporting context, this study aimed to assess the impact of congruence between perceived and preferred leadership behaviours on satisfaction with leadership among college student-athletes in Singapore. Data were collected from 185 college student-athletes enrolled in the five local tertiary institutes. The questionnaire utilized in this study consisted of the perception and preference versions of the Revised Leadership Scale for Sports and seven items measuring satisfaction with coaching leadership. Confirmatory factor analysis and a series of hierarchical multiple regression procedures were carried out to test the psychometric properties of the leadership scale and the hypothesized relationship between congruence levels and satisfaction. Results revealed congruence of perceived and preferred behaviour in social support was a significant indicator of athletes' satisfaction. Possible implications from the findings were discussed in an effort to better understand coaching effectiveness in Singapore.     

“Good Enough”: Developing a Simple Workflow for Open Access Policy Implementation

Academic libraries are often tasked with open access (OA) policy implementation. Many academic libraries have developed robust workflows that utilize custom-built management tools and receive support from a number of library staff. While such workflows certainly streamline the process, their development and management require significant resources. As the number of smaller institutions with OA policies increases, there is a need for solutions that are efficient, flexible, and can be accomplished with minimal resources. Staff at Rice University's Fondren Library developed a simple workflow that populates the institutional repository, freeing up time for OA policy outreach and awareness activities.     

Cell chip array for microfluidic proteomics enabling rapid in situ assessment of intracellular protein phosphorylation

We discuss the ability to perform fluorescent immunocytochemistry, following cell fixation, using a microfluidic array of primary, nonadherent, single CD34+ stem cells. The technique requires small cell samples and proceeds with no cell loss, making it well-suited to monitoring these rare patient-derived cells. The chip allows us to correlate live cell dynamics across arrays of individual cells with post-translational modifications of intracellular proteins, following their exposure to drug treatments. Results also show that due to the microfluidic environment, the time scale of cell fixation was significantly reduced compared to conventional methods, leading to greater confidence in the status of the protein modifications studied.     

Promoting Prenatal Exercise From a Sociocultural and Life-Course Perspective: An “Embodied” Conceptual Framework

Purpose: Prenatal exercise is a health behavior that is receiving growing attention amid concern that women in Western societies are gaining excess weight during pregnancy and contributing to future obesity in both the mother and child. In this article, we draw on insights from the fields of social epidemiology and social theory of the body to examine existing prenatal exercise interventions and to propose a multidimensional framework intended to guide future theorizing and intervention design. Method: A scoping review of existing prenatal exercise programs and interventions focused on controlling gestational weight gain was conducted. Articles published prior to January 2017 were obtained from PubMed and CINAHL, and relevant articles were identified (n = 62) using specified inclusion and exclusion criteria. Identified articles were further analyzed to classify the level(s) of the socioecological model targeted in the intervention or program. Results: The majority of existing interventions target intrapersonal factors during pregnancy and do not attend to the role that cumulative exposure of social and structural disadvantage over the lifetime—not just during the prenatal period—plays in shaping health outcomes. In response, a multidimensional framework is proposed that includes key concepts that facilitate a life-course perspective, as well as attention to the integration of biological and social factors as they relate to health and health-related behaviors. Conclusion: Efforts to promote prenatal exercise and to improve maternal and infant health should attend to how systemic inequality impacts women’s health.     

From ‘cultivators of the soil’ to ‘citizen-soldiers’: physically active education and the nation at Maryland Agricultural College

In 1866, military drill and instruction became part of the curriculum of Maryland Agricultural College as a result of the passage of the Morrill Act of 1862, a law setting the terms for the establishment of agricultural colleges across the USA. The introduction of military instruction meant a direct inclusion of physically active coursework that preceded the widespread emergence of organized physical education courses in American educational institutions. However, this was not the first time physical activity was used and discussed at the college: previously, the uses of physical activity at the college wholly entailed outdoor agricultural practice in which students applied pedagogical training about agricultural techniques in the field. In this paper, we examine early Maryland Agricultural College printed discourse from 1859 to 1886, studying how the college shifted focus from idealizing the Republican male citizen as a physically active farmer or ‘cultivator of the soil’ in the years preceding the American Civil War to a physically active ‘citizen-soldier’ in response to the social and political effects of the conflict. Our analysis sheds light on the historical place of such physical activity coursework within the larger historical narrative of American physical education's emergence, and also provides useful historical context for critically viewing linkages between physical culture, nationalism, agricultural education and the military in contemporary physical education.