Student accounts of space and safety at a South African university: implications for social identities and diversity

Transformation efforts in South African higher education have been under increased scrutiny in recent years, especially following the last years of student activism and calls for decolonization of universities. This article presents data from a participatory photovoice study in which a group of students reflect on their experiences of feeling safe and unsafe at an urban-based historically disadvantaged university. Findings highlight the way in which historical inequalities on the basis of social identities of race, class, and gender, among others, continue to shape experiences, both materially and social-psychologically, in South African higher education. However, and of particular relevance in thinking about a socially just university, participants speak about the value of diversity in facilitating their sense of both material and subjective safety. Thus, a diverse classroom and one that acknowledges and recognizes students across diversities, is experienced as a space of comfort, belonging and safety. Drawing on feminist work on social justice, we argue the importance of lecturer sensitivity and reflexivity to their own practices, as well as the value of social justice pedagogies that not only focus on issues of diversity and equality but also destabilize dominant forms of didactic pedagogy, and engage students’ diverse experiences and perceptions

Masculinity, sexuality and vulnerability in 'working' with young men in South African contexts: 'you feel like a fool and an idiot...a loser'

South Africa has seen a rapid increase in scholarship and programmatic interventions focusing on gender and sexuality, and more recently on boys, men and masculinities. In this paper, we argue that a deterministic discourse on men's sexuality and masculinity in general is inherent in many current understandings of adolescent male sexuality, which tend to assume that young women are vulnerable and powerless and young men are sexually powerful and inevitably also the perpetrators of sexual violence. Framed within a feminist, social constructionist the oretical perspective, the current research looked at how the masculinity and sexuality of South African young men is constructed, challenged or maintained. Focus groups were conducted with young men between the ages of 15 and 20 years from five different schools in two regions of South Africa, the Western and Eastern Cape. Data were analysed using Gilligan's listening guide method. Findings suggest that participants in this study have internalised the notion of themselves as dangerous, but were also exploring other possible ways of being male and being sexual, demonstrating more complex experiences of manhood. We argue for the importance of documenting and highlighting the precariousness, vulnerability and uncertainty of young men in scholarly and programmatic work on masculinities.IBS

Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the UV and the visible spectral range

We report on the progress in the study of cascaded GEM and GEM/MHSP gas avalanche photomultipliers operating at atmospheric pressure, with CsI and bialkali photocathodes. They have single-photon sensitivity, ns time resolution and good localization properties. We summarize operational aspects and results, with the highlight of a high-gain stable gated operation of a visible-light device. Of particular importance are the results of a recent ion-backflow reduction study in different cascaded multipliers, affecting the detector's stability and the photocathode's liftime. We report on the significant progress in ion-blocking and provide first results on bialkali-photocathode aging under gas multiplication.Comment: 6 pages, 8 figure

The limits of discourse: masculinity as vulnerability

For many, gender equity being fair to women and men is a zero sum game in which men should be willing to give up their privileges for the creation of a more equitable and just society. The idea that men might benefit from gender equity seems, for many, unthinkable. This was brought home a few years ago in a gender studies test, when students answering a question on what men might gain from gender equality explained instead how women would benefit. In this Perspective I reflect on the ways in which popular discourses around gender may inadvertently undermine movement towards gender and social justice. Dismissing my students' answers as the result of poor teaching or learning misses a key point: It seems to be extraordinarily difficult for most people to recognise how gender creates masculine vulnerabilities or how gender equity could benefit men. I suggest that if we are to improve women's lives through the reduction of violence, feminist teachers and activists need to think creatively about how to help men and boys understand that performances of masculinity deeply compromise their own lives

Laser light scattering (LLS) to observe plasma impact on the adhesion of micrometer-sized particles to a surface

Laser light scattering (LLS) method, combined with a long-distance microscope was utilized to detect micrometer-sized particles on a smooth substrate. LLS was capable to detect individual particle release, shrink, or fragmentation during exposure to a plasma or a gas jet. In-situ monitoring of hundreds of particles was carried out to investigate the effect of hydrogen plasma exposure on particle adhesion, morphology, and composition. LLS was calibrated with monodisperse melamine resin spheres with known sizes of 2.14 µm, 2.94 µm, and 5.26 µm in diameter. The lowest achievable noise level of approximately 3% was demonstrated for counting 5.26 µm spherical melamine particles. The accuracy for melamine particle size measurements ranged from 50% for 2.14 µm particles to 10% for 5.26 µm particles. This scatter was taken as the imprecision of the method. Size distribution for polydisperse particles with known refractive index was obtained by interpolating to an effective scattering cross-section of a sphere using Mie theory. While the Abbe diffraction limit was about 2 µm in our system, the detection limit for Si particles in LLS according to Mie approximation was assessed to about 3 µm, given the limitations of the laser flux, microscope resolution, camera noise, and particle composition. Additionally, the gradual changes in forward scattering cross-sections for Si particles during the exposure to the hydrogen plasma were consistent with Si etching reported in the literature.</p

Plasma Dynamics

Contains reports on four research projects.National Science Foundation (Grant ECS82-13485)University of Maryland (Subcontract A200728)U.S. Air Force - Office of Scientific Research (Grant AFOSR-84-0026B)U.S. Department of Energy (Contract DE-ACO2-78-ET-51013)National Science Foundation (Grant ECS82-13430

Plasticity of the Muscle Stem Cell Microenvironment

Satellite cells (SCs) are adult muscle stem cells capable of repairing damaged and creating new muscle tissue throughout life. Their functionality is tightly controlled by a microenvironment composed of a wide variety of factors, such as numerous secreted molecules and different cell types, including blood vessels, oxygen, hormones, motor neurons, immune cells, cytokines, fibroblasts, growth factors, myofibers, myofiber metabolism, the extracellular matrix and tissue stiffness. This complex niche controls SC biology-quiescence, activation, proliferation, differentiation or renewal and return to quiescence. In this review, we attempt to give a brief overview of the most important players in the niche and their mutual interaction with SCs. We address the importance of the niche to SC behavior under physiological and pathological conditions, and finally survey the significance of an artificial niche both for basic and translational research purposes

Bayesian Linking of Geosynchronous Orbital Debris Tracks as seen by the Large Synoptic Survey Telescope

We describe a Bayesian sampling model for linking and constraining orbit models from angular observations of "streaks" in optical telescope images. Our algorithm is particularly suited to situations where the observation times are small fractions of the orbital periods of the observed objects or when there is significant confusion of objects in the observation field. We use Markov Chain Monte Carlo to sample from the joint posterior distribution of the parameters of multiple orbit models (up to the number of observed tracks) and parameters describing which tracks are linked with which orbit models. Using this algorithm, we forecast the constraints on geosynchronous (GEO) debris orbits achievable with the planned Large Synoptic Survey Telescope (LSST). Because of the short 15 second exposure times, preliminary orbit determinations of GEO objects from LSST will have large and degenerate errors on the orbital elements. Combined with the expected crowded fields of GEO debris it will be challenging to reliably link orbital tracks in LSST observations given the currently planned observing cadence.Comment: 12 pages, 6 figures. Accepted for publication in Advances in Space Researc