1,399 research outputs found

    Paper Session II-C - Infrastructure for a Lunar Base

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    Exploration of the Moon is the most crucial and decisive step for human expansion into the vast reaches of space. The Moon is the natural and ideal testbed for determining human capability to survive, function, expand and settle into the space environment. Scientific studies, astronomic observations, and exploitation and utilization of space resources culminating in the establishment of a self-sufficient permanently human-tended lunar base are the goals of lunar exploration. Four development stages in the evolutionary exploration of the Moon are suggested: (1) exploratory; (2) pioneering; (3) outpost; and (4) base. Overall goals and specific objectives, functional requirements, construction conditions, and life support systems requirements needed in each stage are identified

    Study of wind loading on tall structures: Atlantic-Richfield Plaza buildings, A

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    CER68-69WZS-JEC-GH-36.August 1969.Includes bibliographical references.For Metronics Associates, Inc.Wind loading on a 1:384 scale model of Atlantic-Richfield Plaza Buildings 666 ft. high was investigated in a thick turbulent boundary-layer wind tunnel. Measurements of mean velocity, turbulence intensity and boundary-layer thickness upstream of the model structure verified that the wind-tunnel flow was an adequate simulation of the atmospheric-surface-layer conditions over the full-scale urban area. Mean pressure and pressure fluctuations were measured for three different wind directions (NE, N and NW). Generally, the mean pressure was found to be the largest near the top and smallest close to the base. An opposite variation was observed for the fluctuating and instantaneous peak pressures. The largest pressure fluctuations were obtained in the case of the N wind. The turbulence energy spectra of the upstream flow and surface pressure-fluctuations spectra exhibited consistently a similar qualitative behavior. This is suggestive that the upstream turbulence has a predominant role, together with the wake, in producing the pressure fluctuations. Direct measurement of mean and fluctuating overturning moment by means of a strain-gage dynamometer revealed that the latter ranged up to about ± 34% of the former. Root-mean square values of the fluctuating moment were also determined in an effort to relate it to the pressure fluctuations and upstream turbulence

    Flow field within and above a forest canopy: task I, study of airflow in simulated temperate and tropical forest canopies, Fort Huachuca

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    CER69-70WZS-JEC-TK-6.July 1969.Includes bibliographical references (pages 32-35).For Atmospheric Sciences Laboratory U.S. Army Electronics Command Fort Monmouth, N. J.The velocity and longitudinal turbulence intensity distributions inside and above a forest canopy along its center line were investigated. For this purpose a model forest canopy was used in a meteorological wind tunnel. The results indicate that the flow may be divided into an entrance and fully developed region followed by a short adjustment distance close to canopy end. The entrance region has a decisive effect on the flow characteristics through the canopy. The velocity and turbulence inside the canopy are strongly affected by its structure. A similar qualitative variation for both velocity and turbulence was found in and above the canopy. Its influence stretches over more than 4 roughness heights above it. Generally, the results are in relatively reasonable agreement with field measurements. Investigation of the modified logarithmic law for describing the velocity profile above the canopy revealed that both flow parameters, i.e., friction velocity and roughness length, are not local constants. On the contrary, they vary drastically with height. It is suspected that this is due to the fact the assumption of constant shear stress throughout the boundary layer or significant portions of it is not satisfied

    Wind study of Kaiser Center office building

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    CER69-70GH-JEC-WZS-13.September 1969.For Metronics Associates, Inc.Includes bibliographical references.Mean and fluctuating wind loading on a 1:192 scale model of Kaiser Center Office Building 403 ft high was studied in a uniform flow. Pressure measurements were carried out for four different wind directions (N, NE, E, and S). The wind loading was influenced strongly by a tall building immediately to the southeast when the wind was from the south, Generally, the mean pressure was higher at the center portion of an upwind face than near its edges. On the leewind surface relatively uniform negative pressure (suction) was obtained. Its absolute value was about one-third of that along an upwind face. On the other hand, the fluctuating pressure was highest near the building base, in the flow separation region and in the wake of the adjacent building in a southly wind. A model of the upstream topography to the northeast was constructed using a 1:600 scale. This model terrain was 24 ft long (2.7 miles of the prototype terrain) with the Kaiser building site near its trailing edge. Mean velocity and turbulence intensity profiles were measured along the terrain

    A framework for applying natural language processing in digital health interventions

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    BACKGROUND: Digital health interventions (DHIs) are poised to reduce target symptoms in a scalable, affordable, and empirically supported way. DHIs that involve coaching or clinical support often collect text data from 2 sources: (1) open correspondence between users and the trained practitioners supporting them through a messaging system and (2) text data recorded during the intervention by users, such as diary entries. Natural language processing (NLP) offers methods for analyzing text, augmenting the understanding of intervention effects, and informing therapeutic decision making. OBJECTIVE: This study aimed to present a technical framework that supports the automated analysis of both types of text data often present in DHIs. This framework generates text features and helps to build statistical models to predict target variables, including user engagement, symptom change, and therapeutic outcomes. METHODS: We first discussed various NLP techniques and demonstrated how they are implemented in the presented framework. We then applied the framework in a case study of the Healthy Body Image Program, a Web-based intervention trial for eating disorders (EDs). A total of 372 participants who screened positive for an ED received a DHI aimed at reducing ED psychopathology (including binge eating and purging behaviors) and improving body image. These users generated 37,228 intervention text snippets and exchanged 4285 user-coach messages, which were analyzed using the proposed model. RESULTS: We applied the framework to predict binge eating behavior, resulting in an area under the curve between 0.57 (when applied to new users) and 0.72 (when applied to new symptom reports of known users). In addition, initial evidence indicated that specific text features predicted the therapeutic outcome of reducing ED symptoms. CONCLUSIONS: The case study demonstrates the usefulness of a structured approach to text data analytics. NLP techniques improve the prediction of symptom changes in DHIs. We present a technical framework that can be easily applied in other clinical trials and clinical presentations and encourage other groups to apply the framework in similar contexts

    Survey of micrometeorological parameters within a forest canopy at Fort Polk, Louisiana, A

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    CER80-81WZS-FWL-WEM44.Includes bibliographical references (page 44).February 1982.A field investigation of micrometeorological parameters inside and above a forest canopy at Fort Polk, Louisiana, was conducted in conjunction with the Atmospheric Sciences Laboratory Dusty Infrared Test IIIA. The three orthogonal components of the wind, ory- and wet-bulb temperatures and total solar radiation were measured inside this forest canopy by means of an instrumented meteorological tower. In addition, turbulence inside the forest canopy was monitored by means of hot-wire anemometers. Tethersonde balloon sounding above the forest canopy was further performed. The meteorological data was reduced by means of three different statistical methods. Single sample period values, one-minute sample averages and sequential sample values were computed. The latter two methods led to the construction of time series which can readily be used to perform advanced statistical analyses. Totals of 27 h 29 min of meteorological tower data and 2 h 50 min of balloon data were reduced. The results are presented in tabular form in 1422 tables and partially displayed in 1795 figures under separate cover in view of their large volume. Selected samples of the results are, however, presented herein. The results supply a data base for analyses of airflow in a forest canopy. Suggestions for future work of significance for mission-oriented cases and for modeling of airflow in a forest canopy are outlined.Contract DAAG29-76-D-0100 conducted for the U.S. Army Atmospheric Sciences Laboratory, White Sands Missile Range

    Experiment for Testing Special Relativity Theory

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    An experiment aimed at testing special relativity via a comparison of the velocity of a non matter particle (annihilation photon) with the velocity of the matter particle (Compton electron) produced by the second annihilation photon from the decay Na-22(beta^+)Ne-22 is proposed.Comment: 7 pages, 1 figure, Report on the Conference of Nuclear Physics Division of Russian Academy of Science "Physics of Fundamental Interactions", ITEP, Moscow, November 26-30, 200

    Epigenetic regulation of 5α reductase-1 underlies adaptive plasticity of reproductive function and pubertal timing

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    Women facing increased energetic demands in childhood commonly have altered adult ovarian activity and shorter reproductive lifespan, possibly comprising a strategy to optimize reproductive success. Here we sought to understand the mechanisms of early-life programming of reproductive function, by integrating analysis of reproductive tissues in an appropriate mouse model with methylation analysis of proxy tissue DNA in a well-characterized population of Bangladeshi migrants in the UK. Bangladeshi women whose childhood was in Bangladesh were found to have later pubertal onset and lower age-matched ovarian reserve than Bangladeshi women who grew-up in England. Subsequently we aimed to explore the potential relevance to the altered reproductive phenotype of one of the genes that emerged from the screens. Results: Of the genes associated with differential methylation in the Bangladeshi women whose childhood was in Bangladesh as compared to Bangladeshi women who grew up in the UK, 13 correlated with altered expression of the orthologous gene in the mouse model ovaries. These mice had delayed pubertal onset and a smaller ovarian reserve compared to controls. The most relevant of these genes for reproductive function appeared to be SRD5A1, which encodes the steroidogenic enzyme 5α reductase-1. SRD5A1 was more methylated at the same transcriptional enhancer in mice ovaries as in the women’s buccal DNA, and its expression was lower in the hypothalamus of the mice as well, suggesting a possible role in the central control of reproduction. The expression of Kiss1 and Gnrh was also lower in these mice compared to controls, and inhibition of 5α reductase-1 reduced Kiss1 and Gnrh mRNA levels and blocked GnRH release in GnRH neuronal cell cultures. Crucially, we show that inhibition of this enzyme in female mice in vivo delayed pubertal onset. Conclusions: SRD5A1/5α reductase-1 responds epigenetically to the environment and its down-regulation appears to alter the reproductive phenotype. These findings help to explain diversity in reproductive characteristics and how they are shaped by early-life environment, and reveal novel pathways that might be targeted to mitigate health issues caused by life-history trade-offs

    Prospective Study of Violence Risk Reduction by a Mental Health Court

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    Although many mental health courts (MHCs) have been established to reduce criminal justice involvement of persons with mental disorders, research has not kept pace with the widespread implementation of these courts. Whereas early MHCs were restricted to persons charged with nonviolent misdemeanors, many MHCs now accept persons with more serious charges for whom ameliorating risk of violence is a greater concern. This study evaluated the relationship between MHC participation and risk of violence by using a prospective design. It was hypothesized that MHC participation would decrease the risk of violence during a one year follow-up compared with a matched comparison group.The sample included 169 jail detainees with a mental disorder who either entered an MHC (N=88) or received treatment as usual (N=81). Seventy-two percent had been charged with felonies. Participants were interviewed at baseline and during a one-year follow up, and their arrest records were reviewed. Propensity-adjusted logistic regression evaluated the relationship between MHC participation and risk of violence, controlling for potential confounders such as history of violence, demographic characteristics, baseline treatment motivation, and time at risk in the community.MHC participation was associated with reduction in risk of violence (odds ratio=.39). During follow-up, 25% of the MHC group perpetrated violence, compared with 42% of the treatment-as-usual group.MHC participation can reduce the risk of violence among justice-involved persons with mental disorders. The findings support the conclusion that the MHC model can be extended beyond persons charged with nonviolent misdemeanors in a way that enhances public safety

    Evolution of Massive Haloes in non-Gaussian Scenarios

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    We have performed high-resolution cosmological N-body simulations of a concordance LCDM model to study the evolution of virialized, dark matter haloes in the presence of primordial non-Gaussianity. Following a standard procedure, departures from Gaussianity are modeled through a quadratic Gaussian term in the primordial gravitational potential, characterized by a dimensionless non-linearity strength parameter f_NL. We find that the halo mass function and its redshift evolution closely follow the analytic predictions of Matarrese et al.(2000). The existence of precise analytic predictions makes the observation of rare, massive objects at large redshift an even more attractive test to detect primordial non-Gaussian features in the large scale structure of the universe.Comment: 7 pages,3 figures, submitted to MNRA
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