5,081 research outputs found

    Space debris measurement program at Phillips Laboratory

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    Ground-based optical sensing was identified as a technique for measuring space debris complementary to radar in the critical debris size range of 1 to 10 cm. The Phillips Laboratory is building a staring optical sensor for space debris measurement and considering search and track optical measurement at additional sites. The staring sensor is implemented in collaboration with Wright Laboratory using the 2.5 m telescope at Wright Patterson AFB, Dayton, Ohio. The search and track sensor is designed to detect and track orbital debris in tasked orbits. A progress report and a discussion of sensor performance and search and track strategies will be given

    Nuclear incompressibility using the density dependent M3Y effective interaction

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    A density dependent M3Y effective nucleon-nucleon (NN) interaction which was based on the G-matrix elements of the Reid-Elliott NN potential has been used to determine the incompressibity of infinite nuclear matter. The nuclear interaction potential obtained by folding in the density distribution functions of two interacting nuclei with this density dependent M3Y effective interaction had been shown earlier to provide excellent descriptions for medium and high energy α\alpha and heavy ion elastic scatterings as well as α\alpha and heavy cluster radioactivities. The density dependent parameters have been chosen to reproduce the saturation energy per nucleon and the saturation density of spin and isospin symmetric cold infinite nuclear matter. The result of such calculations for nuclear incompressibility using the density dependent M3Y effective interaction based on the G-matrix elements of Reid-Elliott NN potential predicts a value of about 300 MeV for nuclear incompressibility.Comment: 4 Page

    Analysis of circadian rhythms from online communities of individuals with affective disorders

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    The circadian system regulates 24 hour rhythms in biological creatures. It impacts mood regulation. The disruptions of circadian rhythms cause destabilization in individuals with affective disorders, such as depression and bipolar disorders. Previous work has examined the role of the circadian system on effects of light interactions on mood-related systems, the effects of light manipulation on brain, the impact of chronic stress on rhythms. However, such studies have been conducted in small, preselected populations. The deluge of data is now changing the landscape of research practice. The unprecedented growth of social media data allows one to study individual behavior across large and diverse populations. In particular, individuals with affective disorders from online communities have not been examined rigorously. In this paper, we aim to use social media as a sensor to identify circadian patterns for individuals with affective disorders in online communities.We use a large scale study cohort of data collecting from online affective disorder communities. We analyze changes in hourly, daily, weekly and seasonal affect of these clinical groups in contrast with control groups of general communities. By comparing the behaviors between the clinical groups and the control groups, our findings show that individuals with affective disorders show a significant distinction in their circadian rhythms across the online activity. The results shed light on the potential of using social media for identifying diurnal individual variation in affective state, providing key indicators and risk factors for noninvasive wellbeing monitoring and prediction

    The Vietnamese version of the Perceived Stress Scale (PSS-10): Translation equivalence and psychometric properties among older women.

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    BACKGROUND: The Perceived Stress Scale 10 item (PSS-10) has been translated into more than 20 languages and used widely in different populations. Yet, to date, no study has tested psychometric properties of the instrument among older women and there is no Vietnamese version of the instrument. METHODS: This study translated the PSS-10 into Vietnamese and assessed Vietnamese version of the Perceived Stress Scale 10 items (V-PSS-10) for translation equivalence, face validity, construct validity, correlations, internal consistency reliability, and test-retest reliability among 473 women aged 60 and over. RESULTS: The study found that V-PSS-10 retained the original meaning and was understood by Vietnamese older women. An exploratory factor analysis of the V-PSS-10 yielded a two-factor structure, and these two factors were significantly correlated (0.56, p < .01) with all item loadings exceeded .50. The V-PSS-10 score was positively correlated with general sleep disturbance (ρ = .12, p < .05), CES-D score for depression symptoms (ρ = .60, p < .01), and negatively correlated with mental (ρ = -.46, p < .01), and physical health scores (ρ = -.19, p < .01). The Cronbach's alpha for the V-PSS-10 was .80, and the test-retest correlation at one month's interval was .43. CONCLUSION: Findings from this study suggest that the V-PSS-10 has acceptable validity and reliability levels among older women. The V-PSS-10 can be used to measure perceived stress in future research and practice. However, future research would be useful to further endorse the validity and reliability of the V-PSS-10

    How life stressors influence modifiable lifestyle factors, depressive symptoms, and physical and mental health among Vietnamese older women?

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    BACKGROUND: Research has demonstrated that exposure to life stressors can influence health through a number of pathways. However, knowledge about the patterns of life stressors and their contributions to health in different populations is limited. Vietnamese older women have attracted little research to date in this area. METHODS: This cross-sectional study used an interview-administered-questionnaire to collect data from 440 Vietnamese older women. Descriptive analysis was used to describe life stressors among Vietnamese older women. Binary analysis and Structural Equation Modelling statistical analysis were used to examine the influences of life stressors on modifiable lifestyle factors, depressive symptoms, physical and mental health among Vietnamese older women. RESULTS: Vietnamese older women in this study commonly reported the experience of losing a close person, including a baby/child, serious health or money problems, violence and disaster. Among the study participants, (1) exposure to more life stressors increased their depressive symptoms, and decreased their physical and mental health; (2) exposure to more life stressors also increased their physical health by increasing their physical activity levels. CONCLUSION: Life stressors influenced health among Vietnamese older women through different pathways. Interventions to manage stress and depressive symptoms are required for Vietnamese older women in the future

    Smoke-free environment policy in Vietnam : what did people see and how did they react when they visited various public places?

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    Introduction. Since Vietnam has signed WHO framework on tobacco control (FCTC) in 2003 and has issued tobacco control law in 2013, there has been little research concerning about what impacts smoke-free regulations have had on public compliance. The objective of this study was to assess public exposure to secondhand smoke and reaction toward smoke-free policy regulations in Vietnam and the associated factor. Methods. Using the design of GATS (Global Adult Tobacco Survey), a nationally representative sample of 8,996 adults were approached for data collection. Logistic regression was used to examine the associated factor. Results. The study revealed that the prevalence of respondents exposed to secondhand smoke was much higher in bars/café/tea shops (90.07%) and restaurants (81.81%) than in any other public places, universities (36.70%), government buildings (31.12%), public transport (20.04%), healthcare facilities (17.85%) and schools (15.84%). 13.23% of respondents saw smokers violate smoke-free regulations. Among those who saw them violate smoke-free regulations, just onethird cautioned them to stop smoking. Strikingly, a higher rate of cautioning smokers to stop smoking was observed among the older, married, and better educated respondents. Respondents who were married, better educated and in lower economic status were more likely to remind smokers to stop smoking. Conclusions. The study has called for strengthening two of the six MPOWER (Monitor, Protect, Offer, Warn, Enforce and Raise) components of the tobacco free initiative introduced by WHO, Monitoring tobacco use and prevention policies and Protecting people from tobacco smoke. © 2019 Pacini Editore SPA. All rights reserved. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Huy Nguyen” is provided in this record*

    A cross-cultural comparison of health-related quality of life and its associated factors among older women in Vietnam and Australia.

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    This study compared health-related quality of life and its associated factors among 305 women in Vietnam and 175 women in Australia aged 60-71. Descriptive analyses, Chi square, independent t-tests, and General Linear Models were used for data analysis.After controlling for socio-demographics, lifestyles, and chronic diseases, older women in Vietnam had lower levels of physical health but similar levels of mental health to those in Australia. In both populations, chronic disease and diet were associated with physical health; physical activity was related to mental health. In Australia, physical activity, exercise, and Body Mass Index were also associated with physical health; age, alcohol consumption, and sleep were also linked with mental health. In Vietnam, age and marital status were also related to physical health; chronic diseases and diet were also correlated with mental health. These findings suggested that interventions developed in Australia targeting the management of diet and physical activity, may be useful for older women in Vietnam. However, future interventions in Vietnam need to be tailored to account for different age groups, marital status, and the number of chronic diseases experienced. Further investigation into the contributions of cultural factors to health-related quality of life is recommended

    Rubric-based holistic review represents a change from traditional graduate admissions approaches in physics

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    Rubric-based admissions are claimed to help make the graduate admissions process more equitable, possibly helping to address the historical and ongoing inequities in the U.S. physics graduate school admissions process that have often excluded applicants from minoritized races, ethnicities, genders, and backgrounds. Yet, no studies have examined whether rubric-based admissions methods represent a fundamental change of the admissions process or simply represent a new tool that achieves the same outcome. To address that, we developed supervised machine learning models of graduate admissions data collected from our department over a seven-year period. During the first four years, our department used a traditional admissions process and switched to a rubric-based process for the following three years, allowing us to compare which parts of the applications were used to drive admissions decisions. We find that faculty focused on applicants' physics GRE scores and grade point averages when making admissions decisions before the implementation of the rubric. While we were able to develop a sufficiently good model whose results we could trust for the data before the implementation of the rubric, we were unable to do so for the data collected after the implementation of the rubric, despite multiple modifications to the algorithms and data such as implementing Tomek Links. Our inability to model the second data set despite being able to model the first combined with model comparison analyses suggests that rubric-based admissions does change the underlying process. These results suggest that rubric-based holistic review is a method that could make the graduate admissions process in physics more equitable.Comment: Follow up to arXiv:2110.04329; Parts of manuscript originally published as a conference paper (arXiv:1907.01570
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