Spheromak formation and sustainment studies at the sustained spheromak physics experiment using high-speed imaging and magnetic diagnostics

A high-speed imaging system with shutter speeds as fast as 2 ns and double frame capability has been used to directly image the formation and evolution of the sustained spheromak physics experiment (SSPX) [E. B. Hooper et al., Nucl. Fusion 39, 863 (1999)]. Reproducible plasma features have been identified with this diagnostic and divided into three groups, according to the stage in the discharge at which they occur: (i) breakdown and ejection, (ii) sustainment, and (iii) decay. During the first stage, plasma descends into the flux conserver shortly after breakdown and a transient plasma column is formed. The column then rapidly bends and simultaneously becomes too dim to photograph a few microseconds after formation. It is conjectured here that this rapid bending precedes the transfer of toroidal to poloidal flux. During sustainment, a stable plasma column different from the transient one is observed. It has been possible to measure the column diameter and compare it to CORSICA [A. Tarditi et al., Contrib. Plasma Phys. 36, 132 (1996)], a magnetohydrodynamic equilibrium reconstruction code which showed good agreement with the measurements. Elongation and velocity measurements were made of cathode patterns also seen during this stage, possibly caused by pressure gradients or E×B drifts. The patterns elongate in a toroidal-only direction which depends on the magnetic-field polarity. During the decay stage the column diameter expands as the current ramps down, until it eventually dissolves into filaments. With the use of magnetic probes inserted in the gun region, an X point which moved axially depending on current level and toroidal mode number was observed in all the stages of the SSPX plasma discharge

Hydrogen depolarized carbon dioxide concentrator performance improvements and cell pair structural tests

The investigations and testing associated with the CO2 removal efficiency and voltage degradation of a hydrogen depolarized carbon oxide concentrator are reported. Also discussed is the vibration testing of a water vapor electrolysis cell pair. Performance testing of various HDC cell pairs with Cs2CO3 electrolyte provided sufficient parametric and endurance data to size a six man space station prototype CO2 removal system as having 36 HDC cell pairs, and to verify a life capability exceeding six moths. Testing also demonstrated that tetramethylammonium carbonate is an acceptable HDC electrolyte for operating over the relative humidity range of 30 to 90 percent and over a temperature range of 50 to 80 F

Less Traditional – More Conceptual: Enhancing Student Learning in First-Year Biology

Over the last two decades, a number of influential reports have called for fundamental changes to undergraduate science education. Most importantly, these reports advocate a shift from traditional lecture-based teaching formats to ones that use student-focused pedagogies to encourage deep student learning about key conceptual ideas in science. Based on these reports, and the underlying research, the University of Calgary completed an extensive redesign of its first-year biology courses in 2011, resulting in two courses: Energy Flow in Biological Systems and DNA, Inheritance and Evolution. These courses focus student learning on two foundational concepts and use student-centered pedagogies to encourage the development of critical-thinking and problem-solving skills. Pre/post data collected from one year of the previous introductory courses and two years of the redesigned courses were used to determine the impact of the transition to a conceptual-based curriculum and the incorporation of active learning strategies including clickers and in-class group assignments on student learning gains measured via normalized change using questions from Biological Concept Inventory, Respiration and Photosynthesis Diagnostic Question Clusters and the Conceptual Inventory of Natural Selection. Student motivations and approaches for learning (e.g. deep versus surface approaches) using the published Approaches and Study Skills Inventory for Students (ASSIST) survey and the Experiences of Teaching and Learning Questionnaire (ETLQ). Data show significantly higher learning gains during the two consecutive years of implementation of the redesigned courses than those achieved in the previous format. Additionally, students reported that lecture activities allowed them being more engaged with course content. We are currently analyzing student written responses, which will provide further insight into the impact of course redesign on content knowledge and critical reasoning skills on student success

Evaluating student learning in large introductory biology courses: predictors of student success and lessons for course redesign

In 2009, the University of Calgary began an extensive redesign of its first-year biology courses based on survey feedback from both students and faculty, as well as the extensive literature showing the effectiveness of student-centered pedagogies in enhancing student learning, engagement and retention in large classes. The two newly designed courses, Energy Flow in Biological Systems and DNA, Inheritance and Evolution are concept-based courses that emphasize the integration of key concepts from biomolecules to the biosphere within a student-centered learning environment; these courses begin in Fall 2011. In order to understand the factors influencing student success in first-year biology, we have initiated a three-year mixed-methods investigation of students’ a priori knowledge, motivations, and approaches to learning. In our current first-year courses, we collected data related to changes in both student motivation and learning over the entire first year for 750 students. The strongest predictors of student success, based on grades earned in the lecture component of the course, were multiple-choice pre-test scores (

Physicochemical characterization of the PEG8000-Na2SO4 aqueous two-phase system

The polyethylene glycol-sodium sulfate aqueous two-phase system has been characterized at 23 °C. Tielines for the phase diagram were obtained experimentally. Phases in equilibrium were characterized by means of the solvatochromic parameters π*, α, and β, which provide a measurement of the polarity/polarizability and the H-bond donor and acceptor abilities, respectively. The ability of the phases to participate in hydrophobic interactions was characterized by means of the free energy of transfer of a methylene group between the conjugated phases, using the partition of a homologous series of dinitrophenylated amino acids. The results show the effect of the presence of polymer and salt in the aqueous phase, and a comparison of both phases with pure water is made.LSRE-PortoUniversidade Católica PortuguesaEscola Superior de Biotecnologia do PortoFundação para a Ciência e a Tecnologia (FCT

Economic impacts of the United States of siting decisions for the international thermonuclear experimental reactor: Executive summary

This summary highlights the results of a study that examined and compared the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S. or (2) ITER were to be sited in one of the other countries that, along with the U.S., are currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning were analyzed to assess their economic impact. A number of possible U.S. {open_quotes}host{close_quotes} and U.S. {open_quotes}non-host{close_quotes} technology and cost-sharing arrangements were examined. The study examined both national and local/regional economic impacts, as measured by gross domestic product (GDP), regional output, employment, income, and net exports. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER

"Just Going Through the Motions.…": A Qualitative Exploration of Athlete Perceptions of Social Loafing in Training and Competition Contexts - Implications for Team Sport Coaches

Semi-structured interviews were conducted with twenty team sport athletes representing a range of different sports with the aim of investigating their views relating to social loafing in training and competition. General themes investigated and subsequent content analysis highlighted factors that promote or reduce the extent of social loafing. Determinants of self-loafing were grouped according to three distinct categories: Group processes; Task characteristics and Individual perceptions. Social loafing among others was perceived to be prevalent in both the training and competition scenarios with more examples of social loafing provided in the training situation. The signs of social loafing were grouped according to the following themes: Cognitive & Emotional, Behavioural, Communication and Player Intuition. Consequences of social loafing were found to be detrimental to the effort and performance of both the individual and the team. Athletes were also able to differentiate between perceived social loafing and the perceived use of ‘strategic rest’ in team sports. Implications for the coaching process are far reaching with the need to develop an effective team culture and to provide training sessions that are interesting, engaging and relevant

Less is more: possibility and necessity as centres of gravity in a usage-based classification of core modals in Polish

In this paper we present the results of an empirical study into the cognitive reality of existing classifications of modality using Polish data. We analyzed random samples of 250 independent observations for the 7 most frequent modal words (móc, można, musieć, należy, powinien, trzeba, wolno), extracted from the Polish national corpus. Observations were annotated for modal type according to a number of classifications, including van der Auwera and Plungian (1998), as well as for morphological, syntactic and semantic properties using the Behavioral Profiling approach (Divjak and Gries 2006). Multiple correspondence analysis and (polytomous) regression models were used to determine how well modal type and usage align. These corpus-based findings were validated experimentally. In a forced choice task, naive native speakers were exposed to definitions and prototypical examples of modal types or functions, then labeled a number of authentic corpus sentences accordingly. In the sorting task, naive native speakers sorted authentic corpus sentences into semantically coherent groups. We discuss the results of our empirical study as well as the issues involved in building usage-based accounts on traditional linguistic classifications

The Dead Butler revisited: grammatical accuracy and clarity in the English Primary Curriculum 2013–2014

This paper is an analysis of the strengths and weaknesses of the grammatical description and advice contained in the new National Curriculum documentation from 2013, focusing on key stages 1 and 2. It builds on previous analyses of deficiencies in the systems of grammar and the materials in earlier incarnations of the National Curriculum. It suggests that there have been advances in the accuracy with which grammar terms are used and illustrated, although there is still no coherent overall view of what grammar is, nor a fully consistent approach to describing language. In addition, the lack of any pedagogic guidance save the most basic suggests that knowledge about language may continue to be taught in a way which is incompatible with real understanding and more in line with prescriptivist approaches