Anitproton-matter interactions in antiproton applications

By virtue of the highly energetic particles released when they annihilate in matter, antiprotons have a variety of potentially important applications. Among others, these include remote 3-D density and composition imaging of the human body and also of thick, dense materials, cancer therapy, and spacecraft propulsion. Except for spacecraft propulsion, the required numbers of low energy antiprotons can be produced, stored, and transported through reliance on current or near term technology. Paramount to these applications and to fundamental research involving antiprotons is knowledge of how antiprotons interact with matter. The basic annihilation process is fairly well understood, but the antiproton annihilation and energy loss rates in matter depend in complex ways on a number of atomic processes. The rates, and the corresponding cross sections, were measured or are accurately predictable only for limited combinations of antiproton kinetic energy and material species

The Combined Release and Radiation Effects Satellite (CRRES) program: A unique series of scientific experiments

The Defense Department and NASA have joined in a program to study the space environment which surrounds the earth and the effects of space radiation on modern satellite electronic systems. The Combined Release and Radiation Effects Satellite (CRRES) will carry an array of active experiments including chemical releases and a complement of sophisticated scientific instruments to accomplish these objectives. Other chemical release active experiments will be performed with sub-orbital rocket probes. The chemical releases will 'paint' the magnetic and electric fields of earthspace with clouds of glowing ions. Earthspace will be a laboratory, and the releases will be studied with an extensive network of ground-, aircraft-, and satellite-based diagnostic instruments. Some of the topics discussed include the following: the effects of earthspace; the need for active experiments; types of chemical releases; the CRRES program schedule; international support and coordinated studies; photographing chemical releases; information on locating chemical releases for observation by the amateur; and CRRES as a program

A System for Coding the Interaction in Focus Groups and Dyadic Interviews

Interaction among participants is the fundamental mechanism that generates data in focus groups. Despite calls for ways to analyze interaction in focus groups, there is still an unmet need to develop such tools. We present a coding system to investigate interaction by emphasizing how participants use the substantive aspects of the topics they discuss. We then apply it to the question of how conversations in dyadic interviews (with two participants) compare to discussions in focus groups (with four or more participants). We find that dyadic interviews are more likely to contain explicit connections to the content of the previous speaker’s statement, and to generate more statements of agreement, indicating a higher degree of mutual attunement. These results demonstrate the effectiveness of our coding system in one particular context. We conclude by considering both the limitations of this system and the possibilities for extending it in future research

Iterative Thematic Inquiry: A New Method for Analyzing Qualitative Data

Because themes play such a central role in the presentation of qualitative research results, we propose a new method, Iterative Thematic Inquiry (ITI), that is guided by the development of themes. We begin by describing how ITI uses pragmatism as a theoretical basis for linking beliefs, in the form of preconceptions, to actions, in the form of data collection and analysis. Next, we present the four basic phases that ITI relies on: assessing beliefs; building new beliefs through encounters with data; listing tentative themes; and, evaluating themes through coding. We also review several notable differences between ITI and existing methods for qualitative data analysis, such as thematic analysis, grounded theory, and qualitative content analysis. The use of ITI is then illustrated through its application in a study of exiters from fundamentalist religions. Overall, the two most notable features of ITI are that it begins the development of themes as early as possible, through an assessment of initial preconceptions, and that it relies on writing rather than coding, by using a continual revision of tentative results as the primary procedure for generating a final set of themes

Photoacoustic ultrasound sources from diffusion-limited aggregates

Metallic diffusion-limited aggregate (DLA) films are well-known to exhibit near-perfect broadband optical absorption. We demonstrate that such films also manifest a substantial and relatively material-independent photoacoustic response, as a consequence of their random nanostructure. We theoretically and experimentally analyze photoacoustic phenomena in DLA films, and show that they can be used to create broadband air- coupled acoustic sources. These sources are inexpensive and simple to fabricate, and work into the ultrasonic regime. We illustrate the device possibilities by building and testing an optically-addressed acoustic phased array capable of producing virtually arbitrary acoustic intensity patterns in air.Comment: 5 pages, 5 figure

INNOVATIVE APPROACHES IN COACH EDUCATION PEDAGOGY

ABSTRACT: We know that coach education programmes continue to be criticized for their largely didactic methods of delivery and rather superficial engagement with the complex reality of practice and we understand that innovative approaches in coach education pedagogy means moving somewhat away from the competencies based approach and it has been increasingly argued that the aim of coach education should be to develop in practitioners a ‘quality of mind’ so that they are better equipped to deal with the problematic and dynamic nature of their work. The skills of coach educators in facilitating the learning of student coaches are crucial to the effectiveness of the pedagogies. Coach educators, therefore, must be committed to the approaches outlined in this article and invest the time and work necessary to learning new skills if they are to be successfully implemented. We found that teaching in this way resulted in a raised degree of responsibility on behalf of the tutors, not so much in relation to their content delivery, but for the subsequent student interaction and learning (JONES et al., 2011). In this sense tutors took greater care to listen and react to group interactions, recognising that their (non) interventions at (in) appropriate times could genuinely affect and frame ensuing students’ discussions and perceptions. A further area of research, therefore, could be to explore the issues surrounding the training and support of coach educators in implementing such pedagogical innovative approaches to coach education. RESUMO: Sabemos que os trabalhos de orientação de técnicos/professores são muito criticados por seus métodos pouco se aproximarem de práticas inovadoras. No entanto, práticas pedagógicas inovadoras devem se aproximar da realidade prática e avançar aos métodos tradicionais, considerando que uma pedagogia inovadora deve mover alguém do lugar onde se encontra para conhecer novas possibilidades. As habilidades dos técnicos/professores devem ser trabalhadas no sentido dos mesmos se constituírem facilitadores do processo de aprendizagem dos estudantes para se pensar numa pedagogia inovadora. Entendemos que uma concepção pedagógica construída nessa direção possibilita o desenvolvimento tanto de técnicos/professores, assim como os estudantes e pesquisas educacionais devem caminhar nessa direção, tendo em vista a necessidade de transformação qualitativa dessa áreade atuação.http://dx.doi.org/10.14572/nuances.v24i1.217

A Systematic Comparison of In-Person and Video-Based Online Interviewing

Due to the increasing popularity of online qualitative interviewing methods, we provide a systematically organized evaluation of their advantages and disadvantages in comparison to traditional in-person interviews. In particular, we describe how individual interviews, dyadic interviews, and focus groups operate in both face-to-face and videoconferencing modes. This produces five different areas for comparison: logistics and budget, ethics, recruitment, research design, and interviewing and moderating. We conclude each section with set of recommendations, and conclude with directions for future research in online interviewing

3D Ultrastructure of the Cochlear Outer Hair Cell Lateral Wall Revealed By Electron Tomography.

Outer Hair Cells (OHCs) in the mammalian cochlea display a unique type of voltage-induced mechanical movement termed electromotility, which amplifies auditory signals and contributes to the sensitivity and frequency selectivity of mammalian hearing. Electromotility occurs in the OHC lateral wall, but it is not fully understood how the supramolecular architecture of the lateral wall enables this unique form of cellular motility. Employing electron tomography of high-pressure frozen and freeze-substituted OHCs, we visualized the 3D structure and organization of the membrane and cytoskeletal components of the OHC lateral wall. The subsurface cisterna (SSC) is a highly prominent feature, and we report that the SSC membranes and lumen possess hexagonally ordered arrays of particles. We also find the SSC is tightly connected to adjacent actin filaments by short filamentous protein connections. Pillar proteins that join the plasma membrane to the cytoskeleton appear as variable structures considerably thinner than actin filaments and significantly more flexible than actin-SSC links. The structurally rich organization and rigidity of the SSC coupled with apparently weaker mechanical connections between the plasma membrane (PM) and cytoskeleton reveal that the membrane-cytoskeletal architecture of the OHC lateral wall is more complex than previously appreciated. These observations are important for our understanding of OHC mechanics and need to be considered in computational models of OHC electromotility that incorporate subcellular features

Genetic Bottlenecks In \u3ci\u3ePristis\u3c/i\u3e Sawfishes In Northern Australian Waters

Northern Australia has been identified as the last stronghold for the dwarf sawfish Pristis clavata, green sawfish P. zijsron, and largetooth sawfish P. pristis, making these populations key in global conservation efforts for each species. This research assesses the levels of genetic diversity in these 3 sawfishes in Australian waters, testing for the presence of population bottlenecks using data at microsatellite loci. Levels of observed heterozygosity in each species from the west coast of Australia and the north-eastern Gulf of Carpentaria were generally high. M ratio tests suggest that assemblages of P. zijsron and P. pristis on the west coast and P. clavata and P. zijsron in the Gulf of Carpentaria may have experienced population bottlenecks. The bottlenecks are especially pronounced in P. zijsron populations and in P. clavatafrom the Gulf of Carpentaria. Demographic analyses, based on mtDNA data, indicate relatively recent (evolutionarily) range expansions in Pristis sawfishes in northern Australian waters, which could account for the population bottlenecks. A more recent range expansion in each of P. clavata and P. zijsron, as evidenced by more recent population divergence and more recent/higher rates of historic maternal gene flow, could account for the more pronounced bottlenecks in these species when compared to P. pristis. Given that Pristis sawfishes in Australian waters have experienced population bottlenecks, whether they be historic, contemporary or both, the preservation of remaining genetic diversity should be a high conservation priority