Detection of reactive oxygen and nitrogen species by electron paramagnetic resonance (EPR) technique

During the last decade there has been growing interest in physical-chemical oxidation processes and the behavior of free radicals in living systems. Radicals are known as intermediate species in a variety of biochemical reactions. Numerous techniques, assays and biomarkers have been used to measure reactive oxygen and nitrogen species (ROS and RNS), and to examine oxidative stress. However, many of these assays are not entirely satisfactory or are used inappropriately. The purpose of this chapter is to review current EPR (Electron Paramagnetic Resonance) spectroscopy methods for measuring ROS, RNS, and their secondary products, and to discuss the strengths and limitations of specific methodological approaches

Developing the Guidance Skills of SI Leaders

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Development, competition and Hillbrow: the Inner-City High Schools Drama Festival 2005-2015, a community arts project

This thesis is submitted to the Faculty of Humanities, University of Witwatersrand, in fulfilment of the requirements for the degree of Master of Arts in Arts and Culture Management by dissertation, 2016This study looks into the artistic strategies employed by the Inner-City High Schools Drama Festival to promote an appreciation for arts and culture programmes in inner-city high schools and beyond, and, by extension, reflects on how the festival impacts on participants’ perceptions of Hillbrow as home. Through an analysis of South African art historian Lize van Robbroeck’s conceptual framework of community arts centres, this case study unpacks how site specificities of the centre being in Hillbrow, starts to debunk what has become a widely understood framework of arts centres as inherently pro-marginal, thereby associated with ‘blackness’, both during apartheid and post-apartheid. Qualitative methods such as semi-structured interviews with the Hillbrow Theatre Project staff, facilitators and school teachers, focus group discussions with school-goers, letters and organisational documents have therefore been used in order to get a deeper understanding of the workings of the Outreach Foundation as a centre and its artistic programme under the Hillbrow Theatre Project called the Inner-City High Schools Drama Festival. The study reveals that the artistic strategies employed by the Inner-City High Schools Drama Festival are effective in promoting an appreciation for an arts and culture programme, and it further shows that the festival can indeed effect some measure of change in participants’ attitudes about Hillbrow as home.GR201

What predicts the number of attempts to pass the driving test? A case from Norwegian driving education model

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Modelling of dielectric barrier discharge plasma actuators for direct numerical simulations

In recent years the development of devices known as plasma actuators has advanced the promise of controlling flows in new ways that increase lift, reduce drag and improve aerodynamic efficiencies; advances that may lead to safer, more efficient and quieter aircraft. The large number of parameters (location of the actuator, orientation, size, relative placement of the embedded and exposed electrodes, materials, applied voltage, frequency) affecting the performance of plasma actuators makes their development, testing and optimisation a very complicated task. Several approaches have been proposed for developing numerical models for plasma actuators. The discharge can be modelled by physics-based kinetic methods based on first principles, by semi-empirical phenomenological approaches and by PIV-based methods where the discharge is replaced by a steady-state body force. The latter approach receives a recent interest for its easy implementation in RANS and U-RANS solvers. Here, a forcing term extracted from experiments is implemented into our high-order Navier-Stokes solver (DNS) in order to evaluate its robustness and ability to mimic the effects of a surface dielectric barrier discharge. This experimental forcing term is compared to the numerical forcing term developed by Suzen & Huang (1, 2) with an emphasis on the importance of the wall-normal component of each model

Pengaruh Parameter Proses Terhadap Kekuatan Tarik Produk 3d Printing Menggunakan Filamen Polylactic Acid (PLA) Buatan R3d Maker

Saat ini teknologi di dunia industri manufaktur telah mengalami kemajuan yang sangat pesat salah satunya adalah 3D printing. 3D printing merupakan salah satu teknologi yang mengubah data digital menjadi objek 3D dengan menggunakan proses Additive manufacturing pada saat memproduksi suatu produk. Penelitian ini dilakukan untuk mengetahui pengaruh infill pattern dan nozzle temperature terhadap kekuatan tarik produk 3D printing dengan orientasi sudut pencetakan vertikal sebesar 90° mengggunakan filamen polylactic acid (PLA). Pada penelitian material polylactic acid (PLA) akan dicetak sesuai dengan standar uji tarik ASTM D638-14 Type 4. Variasi parameter proses yang digunakan pada infill pattern berupa lines, cubic, cubic division, quarter cubic, grid, octet, concentric, zig zag, tri hexagon, triangles, gyroid, cross dan cross 3D dan nilai dari nozzle temperature yang digunakan sebesar 205°C, 215°C, dan 225°C. Pada penelitian menunjukan bahwa bahwa infill pattern dan nozzle temperature memiliki pengaruh terhadap kekuatan tarik produk 3D printing dengan orientasi sudut pencetakan vertikal sebesar 0° menggunakan filamen polylactic acid (PLA) Nilai kekuatan tarik tertinggi yang terdapat pada penelitian ini sebesar 42,5 MPa yang menggunakan infill pattern dengan tipe zig zag dan nozzle temperature sebesar 205°C. Sedangkan nilai kekuatan tarik terendah sebesar 30 MPa yang menggunakan infill pattern dengan tipe crossSaat ini teknologi di dunia industri manufaktur telah mengalami kemajuan yang sangat pesat salah satunya adalah 3D printing. 3D printing merupakan salah satu teknologi yang mengubah data digital menjadi objek 3D dengan menggunakan proses Additive manufacturing pada saat memproduksi suatu produk. Penelitian ini dilakukan untuk mengetahui pengaruh infill pattern dan nozzle temperature terhadap kekuatan tarik produk 3D printing dengan orientasi sudut pencetakan vertikal sebesar 0° mengggunakan filamen polylactic acid (PLA). Pada penelitian material polylactic acid (PLA) akan dicetak sesuai dengan standar uji tarik ASTM D638-14 Type 4. Variasi parameter proses yang digunakan pada infill pattern berupa lines, cubic, cubic division, quarter cubic, grid, octet, concentric, zig zag, tri hexagon, triangles, gyroid, cross dan cross 3D dan nilai dari nozzle temperature yang digunakan sebesar 205°C, 215°C, dan 225°C. Pada penelitian menunjukan bahwa bahwa infill pattern dan nozzle temperature memiliki pengaruh terhadap kekuatan tarik produk 3D printing dengan orientasi sudut pencetakan vertikal sebesar 0° menggunakan filamen polylactic acid (PLA) Nilai kekuatan tarik tertinggi yang terdapat pada penelitian ini sebesar 42,5 MPa yang menggunakan infill pattern dengan tipe zig zag dan nozzle temperature sebesar 205°C. Sedangkan nilai kekuatan tarik terendah sebesar 30 MPa yang menggunakan infill pattern dengan tipe cros

Experiences of Supplemental Instruction at Two Scandinavian Universities

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