12,191 research outputs found
Methodology development for evaluation of selective-fidelity rotorcraft simulation
This paper addressed the initial step toward the goal of establishing performance and handling qualities acceptance criteria for realtime rotorcraft simulators through a planned research effort to quantify the system capabilities of 'selective fidelity' simulators. Within this framework the simulator is then classified based on the required task. The simulator is evaluated by separating the various subsystems (visual, motion, etc.) and applying corresponding fidelity constants based on the specific task. This methodology not only provides an assessment technique, but also provides a technique to determine the required levels of subsystem fidelity for a specific task
My preferred pronoun is she: Understanding transgender identity and oral health care needs
This literature review summarizes current research and evidence regarding transgender persons and oral health. Methods: A search of the literature was conducted in the following databases: PubMed, Google Scholar, EBSCO Host, Science Direct, and Wiley Online Library using the keywords transgender identity, gender non-conforming, discrimination, transition, binary systems, transgender oral cavity, transgender, transgender oral health, transgender dental health. Articles published from 2000 to 2017 in both peer-reviewed and non-peer reviewed journals, which reported information regarding the oral health status of transgender populations, were selected for review. Results: The search revealed 18 articles, only 7 of which pertained to the oral health status of transgender client populations. Five other articles were eliminated due to either poor quality or irrelevance. Discussion: The 13 articles included in the review revealed a need for oral health care professionals to be aware that gender is not binary, nor is it a mental health disorder. Transgender people face heightened risk of discrimination, violence, anxiety, depression, suicidality, substance abuse, and sexually transmitted diseases, as well as significant barriers to health care of which oral health professionals should be made aware. Conclusions: Transgender people have the same rights as everyone else to oral health care. Oral health care providers are responsible for ensuring that transgender clients receive care that aligns with their needs and for providing that care in a culturally competent manner. This requires an understanding of the basics of gender nonconformance and its impact on oral-systemic health. Additional research is needed to increase the scientific knowledge base to facilitate improved health outcomes for this client population
Serum lipid levels in normal healthy white South Africans and cape coloured adults living in the Cape Peninsula
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Metallicity Evolution in the Early Universe
Observations of the damped Lya systems provide direct measurements on the
chemical enrichment history of neutral gas in the early universe. In this
Letter, we present new measurements for four damped Lya systems at high
redshift. Combining these data with [Fe/H] values culled from the literature,
we investigate the metallicity evolution of the universe from z~1.5-4.5.
Contrary to our expectations and the predictions of essentially every chemical
evolution model, the N(HI)-weighted mean [Fe/H] metallicity exhibits minimal
evolution over this epoch. For the individual systems, we report tentative
evidence for an evolution in the unweighted [Fe/H] mean and the scatter in
[Fe/H] with the higher redshift systems showing lower scatter and lower typical
[Fe/H] values. We also note that no damped Lya system has [Fe/H] < -2.7 dex.
Finally, we discuss the potential impact of small number statistics and dust on
our conclusions and consider the implications of these results on chemical
evolution in the early universe.Comment: 6 pages, 2 encapsulated figures, Latex2e, uses emulateapj.sty and
onecolfloat.sty. Accepted for publication in ApJ Letters: Feb 28, 200
Distribution of Damped Lyman-alpha Absorbers in a Lambda Cold Dark Matter Universe
We present the results of a numerical study of a galactic wind model and its
implications on the properties of damped Lyman-alpha absorbers (DLAs) using
cosmological hydrodynamic simulations. We vary both the wind strength and the
internal parameters of the the wind model in a series of cosmological SPH
simulations that include radiative cooling and heating by a UV background, star
formation, and feedback from supernovae and galactic winds. To test our
simulations, we examine the DLA `rate-of-incidence' as a function of halo mass,
galaxy apparent magnitude, and impact parameter. We find that the statistical
distribution of DLAs does not depend on the exact values of internal numerical
parameters that control the decoupling of hydrodynamic forces when the gas is
ejected from starforming regions. The DLA rate-of-incidence in our simulations
at z=3 is dominated by the faint galaxies with apparent magnitude R_AB < 25.5.
However, interestingly in a `strong wind' run, the differential distribution of
DLA sight-lines is peaked at Mhalo = 10^{12} Msun/h (R_AB~27), and the mean DLA
halo mass is Mmean=10^{12.4} Msun/h (R_AB ~ 26). These mass-scales are much
larger than those if we ignore winds, because galactic wind feedback suppresses
the DLA cross section in low-mass halos and increases the relative contribution
to the DLA incidence from more massive halos. The DLAs in our simulations are
more compact than the present-day disk galaxies, and the impact parameter
distribution is very narrow unless we limit the search for the host galaxy to
only bright LBGs. The comoving number density of DLAs is higher than that of
LBGs down to R_AB=30 mag if the physical radius of each DLA is smaller than 5
kpc/h_70. We discuss conflicts between current simulations and observations,
and potential problems with simulations based on the CDM model.Comment: 37 pages, 11 figures. Accepted to ApJ. Additional numerical tests of
the internal parameters of the galactic wind model are presente
Ground-Level Magnetic Study of Greene County, Ohio
Author Institution: Department of Physics, Wright State UniversityWe performed a ground level geomagnetic survey of Greene County, Ohio in the fall of 1976. The geomagnetic map showed a positive magnetic anomaly running from the northwestern section to the southeastern section of the county while the remainder of the map was relatively undisturbed. We analyzed the localized anomaly of the southeastern section by the Peters methods and by fitting to the model of a vertical rectangular prism magnetized along the earth's field. The Peters slope and half-slope methods gave maximum depth limits to the top of the body of 1.16 km and 1.08 km respectively. The best fit to the vertical prism model yielded a depth of 1.04±0.05 km, a width of 2.5 ±0.2 km, and a susceptibility contrast of +0.0039 cgs units. From the depth, we concluded that the source of the anomalies is intrabasement susceptibility variations
Preliminary catalog of pictures taken on the lunar surface during the Apollo 15 mission
Catalog of all pictures taken from lunar module or lunar surface during Apollo 15 missio
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