Spin wave dispersion softening in the ferromagnetic Kondo lattice model for manganites

Spin dynamics is calculated in the ferromagnetic (FM) state of the generalized Kondo lattice model taking into account strong on-site correlations between e_g electrons and antiferromagnetic (AFM) exchange among t_{2g} spins. Our study suggests that competing FM double-exchange and AFM super-exchange interaction lead to a rather nontrivial spin-wave spectrum. While spin excitations have a conventional Dq^2 spectrum in the long-wavelength limit, there is a strong deviation from the spin-wave spectrum of the isotropic Heisenberg model close to the zone boundary. The relevance of our results to the experimental data are discussed.Comment: 6 RevTex pages, 3 embedded PostScript figure

The Effect of the Course “Women in Aviation” on College Student Attitudes Regarding Women in the Career Field of Aviation

This study was undertaken to determine whether the course Women in Aviation” had an effect over the time period of the course on college student attitudes on women in aviation. The survey instrument was developed to examine those attitudes. It consisted of 25 statements that invited responses on a five-point Likert-type attitude scale. The survey was administered pre- and post-course with students asked to code their survey forms with an identification number and gender. Comparisons were made between the mean scores of 64 sets of paired responses to each of the statements on pre- and post-course surveys as well as between the mean scores of 60 sets of gender-related responses to the statements. The study suggested the course had an effect on student attitudes and further suggests that the attitude changes that appeared to occur supported women in aviation. The study also seemed to indicate that differences exist between male and female students in their attitudes on women in aviation-related career fields and that these differences persisted over the time period of the course. Finally, this study suggested that there is less agreement among men than among women in their attitudes on women in aviation-related career fields

Shaping citizenship in the classroom:Peer influences on moral disengagement, social goals, and a sense of peer community

Despite the important role of peers in the social process of classroom citizenship, the peer influence related to moral disengagement, social goals, and a sense of peer community remain unclear. To this end, it was examined to what extent youth become similar to their friends in moral disengagement, social goals, and a sense of peer community. Participants were 283 South Korean third to sixth graders (Mage = 9.60 years, SD = 0.97; 51.6% girls) who completed an online survey for moral disengagement, social goals, the sense of peer community and friendship network across the beginning (Time 1) and end (Time 2) of the school semester (September to December). Longitudinal social network analyses indicated that youth became more similar to their friends concerning moral disengagement and a sense of peer community, but did not select friends based on these aspects. The strength of these influence effects varied in terms of different levels of these aspects. Specifically, youth were more likely to become similar to their friends at lower levels of moral disengagement. Youth tended to be similar to the friends' level of sense of peer community. This tendency was relatively strong at the lowest and the highest levels of a sense of peer community. Future research should address the role of friendship in shaping classroom citizenship and the importance of classroom daily teaching practice in youth citizenship development

Real-time monitoring of volatile organic compounds using chemical ionization mass spectroscopy: Final report

Volatile organic compound (VOC) emission to the atmosphere is of great concern to semiconductor manufacturing industries, research laboratories, the public, and regulatory agencies. Some industries are seeking ways to reduce emissions by reducing VOCs at the point of use (or generation). This paper discusses the requirements, design, calibration, and use of a sampling inlet/quadrupole mass spectrometer system for monitoring VOCs in a semiconductor manufacturing production line. The system uses chemical ionization to monitor compounds typically found in the lithography processes used to manufacture semiconductor devices (e.g., acetone, photoresist). The system was designed to be transportable from tool to tool in the production line and to give the operator real-time feedback so the process(es) can be adjusted to minimize VOC emissions. Detection limits ranging from the high ppb range for acetone to the low ppm range fore other lithography chemicals were achieved using chemical ionization mass spectroscopy at a data acquisition rate of approximately 1 mass spectral scan (30 to 200 daltons) per second. A demonstration of exhaust VOC monitoring was performed at a working semiconductor fabrication facility during actual wafer processing

Method for creating gas standards form liquid HFE-7100 and FC-72.

HFE-7100 and FC-72 fluorinert are two fluids used during weapon component manufacturing. HFE-7100 is a solvent used in the cleaning of parts, and FC-72 is the blowing agent of a polymeric removable foam. The presence of either FC-72 or HFE-7100 gas in weapon components can provide valuable information as to the stability of the materials. Therefore, gas standards are needed so HFE-7100 and FC-72 gas concentrations can be accurately measured. There is no current established procedure for generating gas standards of either HFE-7100 or FC-72. This report outlines the development of a method to generate gas standards ranging in concentration from 0.1 ppm to 10% by volume. These standards were then run on a Jeol GC-Mate II mass spectrometer and analyzed to produce calibration curves. We present a manifold design that accurately generates gas standards of HFE-7100 and FC-72 and a procedure that allows the amount of each to be determined

Conceptualising examinable physical education in the Irish context: Leaving Certificate Physical Education

peer-reviewedA Physical Education Development Group (PEDG) was responsible for constructing a new school subject curriculum, Leaving Certificate Physical Education (LCPE), in Ireland. This paper provides an insight into this development group and explores the process of curriculum development, and the influence of roles and power-ratios within the group, in the construction of the LCPE curriculum. Figurational sociology concepts (Elias, 1978) were drawn on to make sense of the curriculum makers’ experiences. Interviews were conducted with 10 PEDG members. The findings suggest that the members’ roles had very little, if any, influence on the curriculum development process. Findings also revolved around the unbalanced power-ratios which existed in the PEDG and highlighted the socially powerful position of ‘strong, well-established’ (in the academic field of curriculum development – participant's words) members and the other members (predominantly representing practicing teachers). We express concern for the role of teachers in the curriculum process and argue that they play a crucial and significant role in the school subject curriculum development process. This paper supports Goodson’s (1983) and Penney’s (2006) conceptualisation of the contested and socially constructed nature of the curriculum development process.peer-reviewe

Beyond screen time: a synergistic approach to a more comprehensive assessment of family media exposure during early childhood

Digital media availability has surged over the past decade. Because of a lack of comprehensive measurement tools, this rapid growth in access to digital media is accompanied by a scarcity of research examining the family media context and sociocognitive outcomes. There is also little cross-cultural research in families with young children. Modern media are mobile, interactive, and often short in duration, making them difficult to remember when caregivers respond to surveys about media use. The Comprehensive Assessment of Family Media Exposure (CAFE) Consortium has developed a novel tool to measure household media use through a web-based questionnaire, time-use diary, and passive-sensing app installed on family mobile devices. The goal of developing a comprehensive assessment of family media exposure was to take into account the contextual factors of media use and improve upon the limitations of existing self-report measures, while creating a consistent, scalable, and cost-effective tool. The CAFE tool captures the content and context of early media exposure and addresses the limitations of prior media measurement approaches. Preliminary data collected using this measure have been integrated into a shared visualization platform. In this perspective article, we take a tools-of-the-trade approach (Oakes, 2010) to describe four challenges associated with measuring household media exposure in families with young children: measuring attitudes and practices; capturing content and context; measuring short bursts of mobile device usage; and integrating data to capture the complexity of household media usage. We illustrate how each of these challenges can be addressed with preliminary data collected with the CAFE tool and visualized on our dashboard. We conclude with future directions including plans to test reliability, validity, and generalizability of these measures