2,187 research outputs found
Augmented Reality: Mapping Methods and Tools for Enhancing the Human Role in Healthcare HMI
Background: Augmented Reality (AR) represents an innovative technology to improve data visualization and strengthen the human perception. Among HumanâMachine Interaction (HMI), medicine can benefit most from the adoption of these digital technologies. In this perspective, the literature on orthopedic surgery techniques based on AR was evaluated, focusing on identifying the limitations and challenges of AR-based healthcare applications, to support the research and the development of further studies. Methods: Studies published from January 2018 to December 2021 were analyzed after a comprehensive search on PubMed, Google Scholar, Scopus, IEEE Xplore, Science Direct, and Wiley Online Library databases. In order to improve the review reporting, the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were used. Results: Authors selected sixty-two articles meeting the inclusion criteria, which were categorized according to the purpose of the study (intraoperative, training, rehabilitation) and according to the surgical procedure used. Conclusions: AR has the potential to improve orthopedic training and practice by providing an increasingly human-centered clinical approach. Further research can be addressed by this review to cover problems related to hardware limitations, lack of accurate registration and tracking systems, and absence of security protocols
HUT observations of carbon monoxide in the coma of Comet Levy (1990c)
Observations of comet Levy (1990c) were made with the Hopkins Ultraviolet Telescope during the Astro-1 Space Shuttle mission on 10 Dec. 1990. The spectrum, covering the wavelength range 415 to 1850 A at a spectral emission of 3 A (in first order), shows the presence of carbon monoxide and atomic hydrogen, carbon, and sulfur in the coma. Aside from H I Lyman-beta, no cometary features are detected below 1200 A, although cometary O I and O II would be masked by the same emissions present in the day airglow spectrum. The 9.4 x 116 arcsec aperture corresponds to 12,000 x 148,000 km at the comet. The derived production rate of CO relative to water, 0.13 + or - 0.02, compared with the same ratio derived from IUE observations (made in Sep. 1990) which sample a much smaller region of the coma, 0.04 + or - 0.01, suggests the presence of an extended source of CO, as was found in comet Halley. Upper limits on Ne and Ar abundance are within an order of magnitude or solar abundances
Oxygen Gas Phase Abundance Revisited
We present new measurements of the interstellar gas-phase oxygen abundance
along the sight lines towards 19 early-type galactic stars at an average
distance of 2.6 kpc. We derive O {\small I} column densities from {\it
HST}/STIS observations of the weak 1355 \AA intersystem transition. We derive
total hydrogen column densities [N(H {\small I})+2N(H)] using {\it
HST}/STIS observations of \lya and {\it FUSE} observations of molecular
hydrogen. The molecular hydrogen content of these sight lines ranges from
f(H) = 2N(H)/[N(H {\small I})+2N(H)] = 0.03 to 0.47. The average
of 6.3 cm mag with a standard
deviation of 15% is consistent with previous surveys. The mean oxygen abundance
along these sight lines, which probe a wide range of galactic environments in
the distant ISM, is 10 \oh = (1 in the mean). %(1 ). We see no evidence for decreasing
gas-phase oxygen abundance with increasing molecular hydrogen fraction and the
relative constancy of \oh suggests that the component of dust containing the
oxygen is not readily destroyed. We estimate that, if 60% of the dust grains
are resilient against destruction by shocks, the distant interstellar total
oxygen abundance can be reconciliated with the solar value derived from the
most recent measurements %by Holweger and by Allende Prieto, Lambert & Asplund:
of 10 \oh = 517 58 (1 ). We note that the smaller
oxygen abundances derived for the interstellar gas within 500 pc %by Meyer,
Cardelli & Jura or from nearby B star surveys are consistent with a local
elemental deficit.Comment: 9 figures, 37 page
A Longitudinal Analysis of the Indirect Effect of Violence Exposure on Future Orientation Through Perceived Stress and the Buffering Effect of Family Participation
Exposure to violence (ETV) during adolescence has been associated with negative effects in later life, and may negatively affect an individualâs future orientation. Future orientation has important health implications and warrants being studied. Yet, few researchers have examined how ETV affects an individualâs future orientation as a young adult. The purpose of this study was to examine the indirect effect of ETV during adolescence on future orientation as a young adult through perceived stress. We also tested the moderating effect of family participation on the relationship between perceived stress and future orientation. Longitudinal data from a sample of 316 African American participants (42.10% male and 57.90% female, Mage = 14.76 at Wave 1) from low socioeconomic backgrounds recruited from a Midwestern school district were used in the analysis. Multigroup structural equation modeling (SEM) was used to test our hypotheses. Our findings indicated that greater ETV during adolescence is associated with higher levels of perceived stress and, in turn, a more negative outlook on oneâs future as a young adult. This indirect effect occurred for individuals with lower family participation, but was not evident for individuals with greater family participation. These findings provide important implications for youth development interventions.HighlightsWe examined how ETV relates to a positive outcome while most researchers focus on negative outcomes.We studied the effects of ETV on future orientation longitudinally.Our findings demonstrate violence exposure to affect future orientation through perceived stress.Our results show that family participation is important for buffering negative effects of stress.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146486/1/ajcp12254.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146486/2/ajcp12254_am.pd
A Study of the Reionization History of Intergalactic Helium with FUSE and VLT
We obtained high-resolution VLT and FUSE spectra of the quasar HE2347-4342 to
study the properties of the intergalactic medium between redshifts z=2.0-2.9.
The high-quality optical spectrum allows us to identify approximately 850 HeII
absorption components with column densities between N~5X10^11 and $ 10^18
cm^-2. The reprocessed FUSE spectrum extends the wavelength coverage of the
HeII absorption down to an observed wavelength of 920 A. Approximately 1400
HeII absorption components are identified, including 917 HeII Ly-alpha systems
and some of their HeII Ly-beta, Ly-gamma, and Ly-delta counterparts. The
ionization structure of HeII is complex, with approximately 90 components that
are not detected in the hydrogen spectrum. These components may represent the
effect of soft ionizing sources. The ratio Eta=N(HeII)/N(HI) varies
approximately from unity to more than a thousand, with a median value of 62 and
a distribution consistent with the intrinsic spectral indices of quasars. This
suggests that the dominant ionizing field is from the accumulated quasar
radiation, with contributions from other soft sources such as star-forming
regions and obscured AGN, which do not ionize helium. We find an evolution in
Eta toward smaller values at lower redshift, with the gradual disappearance of
soft components. At redshifts z>2.7, the large but finite increase in the HeII
opacity, Tau=5+/-1, suggests that we are viewing the end stages of a
reionization process that began at an earlier epoch. Fits of the absorption
profiles of unblended lines indicate comparable velocities between hydrogen and
He^+ ions. At hydrogen column densities N<3X10^12 cm^-2 the number of forest
lines shows a significant deficit relative to a power law, and becomes
negligible below N=10^11 cm^-2.Comment: 40 pages, 10 Postscript figures, uses Aastex.sty The Astrophysical
Journal, in pres
Deuterium Toward WD1634-573: Results from the Far Ultraviolet Spectroscopic Explorer (FUSE) Mission
We use Far Ultraviolet Spectrocopic Explorer (FUSE) observations to study
interstellar absorption along the line of sight to the white dwarf WD1634-573
(d=37.1+/-2.6 pc). Combining our measurement of D I with a measurement of H I
from Extreme Ultraviolet Explorer data, we find a D/H ratio toward WD1634-573
of D/H=(1.6+/-0.5)e-5. In contrast, multiplying our measurements of D I/O
I=0.035+/-0.006 and D I/N I=0.27+/-0.05 with published mean Galactic ISM gas
phase O/H and N/H ratios yields D/H(O)=(1.2+/-0.2)e-5 and
D/H(N)=(2.0+/-0.4)e-5, respectively. Note that all uncertainties quoted above
are 2 sigma. The inconsistency between D/H(O) and D/H(N) suggests that either
the O I/H I and/or the N I/H I ratio toward WD1634-573 must be different from
the previously measured average ISM O/H and N/H values. The computation of
D/H(N) from D I/N I is more suspect, since the relative N and H ionization
states could conceivably vary within the LISM, while the O and H ionization
states will be more tightly coupled by charge exchange.Comment: 23 pages, 5 figures; AASTEX v5.0 plus EPSF extensions in mkfig.sty;
accepted by ApJ Supplemen
- âŠ