Evaluation of selected chemical processes for production of low-cost silicon, phase 3

A Process Development Unit (PDU), which consisted of the four major units of the process, was designed, installed, and experimentally operated. The PDU was sized to 50MT/Yr. The deposition took place in a fluidized bed reactor. As a consequences of the experiments, improvements in the design an operation of these units were undertaken and their experimental limitations were partially established. A parallel program of experimental work demonstrated that Zinc can be vaporized for introduction into the fluidized bed reactor, by direct induction-coupled r.f. energy. Residual zinc in the product can be removed by heat treatment below the melting point of silicon. Current efficiencies of 94 percent and above, and power efficiencies around 40 percent are achievable in the laboratory-scale electrolysis of ZnCl2

Development of a chromium-thoria alloy

Low temperature ductility and high temperature strength of pure chromium and chromium-thoria alloy prepared from vapor deposited powder

Stabilized lasers for advanced gravitational wave detectors

Second generation gravitational wave detectors require high power lasers with more than 100 W of output power and with very low temporal and spatial fluctuations. To achieve the demanding stability levels required, low noise techniques and adequate control actuators have to be part of the high power laser design. In addition feedback control and passive noise filtering is used to reduce the fluctuations in the so-called prestabilized laser system (PSL). In this paper, we discuss the design of a 200 W PSL which is under development for the Advanced LIGO gravitational wave detector and will present the first results. The PSL noise requirements for advanced gravitational wave detectors will be discussed in general and the stabilization scheme proposed for the Advanced LIGO PSL will be described

Ex vivo and in vivo coronary ostial locations in humans

Purpose: Knowledge of the normal in vivo distribution and variation of coronary ostial locations is essential in the planning of various interventional and surgical procedures. However, all studies to date have reported the distribution of coronary ostia locations only in cadaver hearts. In this study, we sought to assess the distribution of coronary ostial locations in patients using cardiac dual-source computed tomography (CT) and compare these values to those of human cadaveric specimens. Methods: Measurements of the coronary ostia location were performed in 150 patients undergoing dual-source CT and in 75 cadavers using open measurement techniques. All 150 patients had a normal aortic valve function and no previous cardiac intervention or surgery. The location of the right and left coronary origin in relation to the aortic annulus and the height of the sinus of Valsalva were measured. Results: Mean ostial locations at CT were 17.0 (±3.6)mm and 15.3 (±3.1)mm for the right and left coronary ostia, with large variations of both sides (right: 10.4-28.5mm; left: 9.8-29.3mm). In cadavers, mean locations were 14.9 (±4.3)mm [5-24mm] for right and 16.0 (±3.6)mm [9-24mm] for left coronary ostia. Comparison of CT and cadaver data showed statistically significant differences for right (P<0.0001) but not left (P=0.1675) coronary ostia. Conclusions: This study provides data of normal coronary ostial origins and demonstrates significant differences between in vivo and ex vivo measurements regarding the right coronary ostium. The observed large variations of coronary ostia origins emphasize the importance of considering such anatomic variations in the development of treatment

Quanto o produtor rural gasta com suas máquinas agrícolas?

Trabalho apresentado no 31º SEURS - Seminário de Extensão Universitária da Região Sul, realizado em Florianópolis, SC, no período de 04 a 07 de agosto de 2013 - Universidade Federal de Santa Catarina.O projeto pretende levantar os gastos que os agricultores têm com a realização das operações mecanizadas durante o processo de produção agropecuária. As ações serão desenvolvidas no Departamento de Agronomia/UEL, Sociedade Rural do Paraná/Londrina e pesquisas de campo, com os produtores rurais, no município de Londrina e região. Durante a sua execução serão levantadas informações e elaboradas planilhas que serão disponibilizadas aos produtores na etapa final de execução do projeto. Com essas informações os produtores poderão conhecer em detalhes seus custos de produção e tomar decisões. O desenvolvimento das atividades do projeto possibilitará formação específica e aprofundada aos estudantes participantes

An ecological dynamics conceptualisation of physical ‘education’: Where we have been and where we could go next

Background: In this paper, we explore physical education from a relational worldview. Theoretically guided by an ecological dynamics framework, this perspective calls us to conceptualise ‘education’ in its etymological roots – ex-ducere – meaning ‘to lead’ an individual ‘out’ into the world. In doing so, an educator would employ a ‘softer’ pedagogy, seeking to guide the attention and encourage exploration of a less experienced individual toward the perception of things that can support, or regulate, their behaviours. This pedagogical approach could help learners to self regulate in the environment, becoming more responsive to emergent opportunities for action available. Theory: This is a pedagogy of exploration, search, discovery, invention and adaptation that is devised from three of the contributing theories to ecological dynamics: ecological psychology, dynamical systems theory and complexity sciences. Throughout this paper we show that this progressive view contrasts with the more traditional perspectives of physical education, grounded in established pedagogical approaches that are often pre-occupied with instilling idealised ways of moving in learners, typically at the expense of appreciating how the environment reciprocally shapes behaviour. Practical Implications: In an effort to support educators with integrating an ecological conceptualisation of PE into their practice we outline three cornerstones. We bring these ideas to life by concluding the paper with the presentation of three practical examples that transcends the physical educational journey from primary/elementary school through to secondary/ high schools. We exemplify how an ecological approach to PE can move us closer to achieving the aim of enabling children to lead a physically active life beyond the school gates

Closed-loop separation control over a sharp edge ramp using Genetic Programming

We experimentally perform open and closed-loop control of a separating turbulent boundary layer downstream from a sharp edge ramp. The turbulent boundary layer just above the separation point has a Reynolds number $Re_{\theta}\approx 3\,500$ based on momentum thickness. The goal of the control is to mitigate separation and early re-attachment. The forcing employs a spanwise array of active vortex generators. The flow state is monitored with skin-friction sensors downstream of the actuators. The feedback control law is obtained using model-free genetic programming control (GPC) (Gautier et al. 2015). The resulting flow is assessed using the momentum coefficient, pressure distribution and skin friction over the ramp and stereo PIV. The PIV yields vector field statistics, e.g. shear layer growth, the backflow area and vortex region. GPC is benchmarked against the best periodic forcing. While open-loop control achieves separation reduction by locking-on the shedding mode, GPC gives rise to similar benefits by accelerating the shear layer growth. Moreover, GPC uses less actuation energy.Comment: 24 pages, 24 figures, submitted to Experiments in Fluid

A canine model of Cohen syndrome: Trapped Neutrophil Syndrome

<p>Abstract</p> <p>Background</p> <p>Trapped Neutrophil Syndrome (TNS) is a common autosomal recessive neutropenia in Border collie dogs.</p> <p>Results</p> <p>We used a candidate gene approach and linkage analysis to show that the causative gene for TNS is <it>VPS13B</it>. We chose <it>VPS13B </it>as a candidate because of similarities in clinical signs between TNS and Cohen syndrome, in human, such as neutropenia and a typical facial dysmorphism. Linkage analysis using microsatellites close to <it>VPS13B </it>showed positive linkage of the region to TNS. We sequenced each of the 63 exons of <it>VPS13B </it>in affected and control dogs and found that the causative mutation in Border collies is a 4 bp deletion in exon 19 of the largest transcript that results in premature truncation of the protein. Cohen syndrome patients present with mental retardation in 99% of cases, but learning disabilities featured in less than half of TNS affected dogs. It has been implied that loss of the alternate transcript of <it>VPS13B </it>in the human brain utilising an alternate exon, 28, may cause mental retardation. Mice cannot be used to test this hypothesis as they do not express the alternate exon. We show that dogs do express alternate transcripts in the brain utilising an alternate exon homologous to human exon 28.</p> <p>Conclusion</p> <p>Dogs can be used as a model organism to explore the function of the alternately spliced transcript of VPS13B in the brain. TNS in Border collies is the first animal model for Cohen syndrome and can be used to study the disease aetiology.</p

Coordination in climbing: effect of skill, practice and constraints manipulation

BACKGROUND: Climbing is a physical activity and sport involving many subdisciplines. Minimization of prolonged pauses, use of a relatively simple path through a route and smooth transitions between movements broadly define skilled coordination in climbing. OBJECTIVES: To provide an overview of the constraints on skilled coordination in climbing and to explore future directions in this emerging field. METHODS: A systematic literature review was conducted in 2014 and retrieved studies reporting perceptual and movement data during climbing tasks. To be eligible for the qualitative synthesis, studies were required to report perceptual or movement data during climbing tasks graded for difficulty. RESULTS: Qualitative synthesis of 42 studies was carried out, showing that skilled coordination in climbing is underpinned by superior perception of climbing opportunities; optimization of spatial-temporal features pertaining to body-to-wall coordination, the climb trajectory and hand-to-hold surface contact; and minimization of exploratory behaviour. Improvements in skilled coordination due to practice are related to task novelty and the difficulty of the climbing route relative to the individual's ability level. CONCLUSION: Perceptual and motor adaptations that improve skilled coordination are highly significant for improving the climbing ability level. Elite climbers exhibit advantages in detection and use of climbing opportunities when visually inspecting a route from the ground and when physically moving though a route. However, the need to provide clear guidelines on how to improve climbing skill arises from uncertainties regarding the impacts of different practice interventions on learning and transfer

Endochondral bone formation in toothless (osteopetrotic) rats: failures of chondrocyte patterning and type X collagen expression

The pacemaker of endochondral bone growth is cell division and hypertrophy of chondrocytes. The developmental stages of chondrocytes, characterized by the expression of collagen types II and X, are arranged in arrays across the growth zone. Mutations in collagen II and X genes as well as the absence of their gene products lead to different, altered patterns of chondrocyte stages which remain aligned across the growth plate (GP). Here we analyze GP of rats bearing the mutation toothless (tl) which, apart from bone defects, develop a progressive, severe chondrodystrophy during postnatal weeks 3 to 6. Mutant GP exhibited disorganized, non-aligned chondrocytes and mineralized metaphyseal bone but without cartilage mineralization or cartilaginous extensions into the metaphysis. Expression of mRNA coding for collagen types II (Col II) and X (Col X) was examined in the tibial GP by in situ hybridization. Mutant rats at 2 weeks exhibited Col II RNA expression and some hypertrophied chondrocytes (HC) but no Col X RNA was detected. By 3rd week, HC had largely disappeared from the central part of the mutant GP and Col II RNA expression was present but weak and in 2 separate bands. Peripherally the GP contained HC but without Col X RNA expression. This abnormal pattern was exacerbated by the fourth week. Bone mineralized but cartilage in the GP did not. These data suggest that the tl mutation involves a regulatory function for chondrocyte maturation, including Col X RNA synthesis and mineralization, and that the GP abnormalities are related to the Col X deficiency. The differences in patterning in the tl rat GP compared to direct Col X mutations may be explained by compensatory effects