469 research outputs found
Mitigation Of Motion Sickness Symptoms In 360 Degree Indirect Vision Systems
The present research attempted to use display design as a means to mitigate the occurrence and severity of symptoms of motion sickness and increase performance due to reduced “general effects” in an uncoupled motion environment. Specifically, several visual display manipulations of a 360° indirect vision system were implemented during a target detection task while participants were concurrently immersed in a motion simulator that mimicked off-road terrain which was completely separate from the target detection route. Results of a multiple regression analysis determined that the Dual Banners display incorporating an artificial horizon (i.e., AH Dual Banners) and perceived attentional control significantly contributed to the outcome of total severity of motion sickness, as measured by the Simulator Sickness Questionnaire (SSQ). Altogether, 33.6% (adjusted) of the variability in Total Severity was predicted by the variables used in the model. Objective measures were assessed prior to, during and after uncoupled motion. These tests involved performance while immersed in the environment (i.e., target detection and situation awareness), as well as postural stability and cognitive and visual assessment tests (i.e., Grammatical Reasoning and Manikin) both before and after immersion. Response time to Grammatical Reasoning actually decreased after uncoupled motion. However, this was the only significant difference of all the performance measures. Assessment of subjective workload (as measured by NASA-TLX) determined that participants in Dual Banners display conditions had a significantly lower level of perceived physical demand than those with Completely Separated display designs. Further, perceived iv temporal demand was lower for participants exposed to conditions incorporating an artificial horizon. Subjective sickness (SSQ Total Severity, Nausea, Oculomotor and Disorientation) was evaluated using non-parametric tests and confirmed that the AH Dual Banners display had significantly lower Total Severity scores than the Completely Separated display with no artificial horizon (i.e., NoAH Completely Separated). Oculomotor scores were also significantly different for these two conditions, with lower scores associated with AH Dual Banners. The NoAH Completely Separated condition also had marginally higher oculomotor scores when compared to the Completely Separated display incorporating the artificial horizon (AH Completely Separated). There were no significant differences of sickness symptoms or severity (measured by self-assessment, postural stability, and cognitive and visual tests) between display designs 30- and 60-minutes post-exposure. Further, 30- and 60- minute post measures were not significantly different from baseline scores, suggesting that aftereffects were not present up to 60 minutes post-exposure. It was concluded that incorporating an artificial horizon onto the Dual Banners display will be beneficial in mitigating symptoms of motion sickness in manned ground vehicles using 360° indirect vision systems. Screening for perceived attentional control will also be advantageous in situations where selection is possible. However, caution must be made in generalizing these results to missions under terrain or vehicle speed different than what is used for this study, as well as those that include a longer immersion time
Arrest or Hospitalization? An Examination of the Relationship Between Psychiatric Symptoms, Traumatic Childhood Experiences, and Socio-Ecological Factors in Forensic Mental Health System Responses to Offender Behavior
It has been well documented that Adverse Childhood Experiences (ACEs) lead to unfavorable outcomes in later life, especially with regard to health and psychological outcomes. Recent research has demonstrated the impact of early childhood adversity on the onset of aggression and illegal behavior. However, often those with mental illness diagnoses with comorbid behavioral problems exhibit trajectories that include both arrest and hospitalization. While some are arrested for their criminal behavior, others are hospitalized. This begs the question: are those with mental illness and behavioral problems more likely to be arrested, or hospitalized, for their early behavioral problems? In the current study, it was hypothesized that arrest precedes hospitalization for the majority of these offenders, and that specific diagnoses of a mental illness are related to outcome. It was also hypothesized that early exposure to environmental adversity, as measured by the age of earliest ACE and total ACE score, would significantly predict whether offenders were arrested or hospitalized first. Other socio-ecological factors were also studied. The data for this study were gathered from a sample of 182 adult psychiatric inpatients in a secure forensic facility. Data were archival and retrospective in nature. All participants had been hospitalized following acts of violence or aggression, exhibiting a history of both behavioral problems as well as mental illness. A series of logistic and linear regressions were used to examine the relationship between reason for first admission to a psychiatric facility, diagnosis of a mental disorder, and early childhood adversity to clarify whether early problematic behaviors resulted in initial arrest or psychiatric hospitalization. Results indicate that subjects were much more likely to be hospitalized initially than arrested (33.5% arrested first, 66.5% hospitalized first). A diagnosis of impulse control disorder was significantly related to whether initial incident led to arrest or hospitalization (p=0.030), while the diagnosis of ADHD neared significance (p=0.056). No significant relationship was found between incidence of initial arrest or hospitalization and age that drug/alcohol abuse began. Other findings and implications for future research will be discussed
Discovery of Numerous Dwarf Galaxies in the Two Nearest Groups of Galaxies
We report the discovery of a large population of dwarf irregular galaxies in
the two nearest groups of galaxies outside the Local Group, the Sculptor and
the Centaurus A groups (2.5 and 3.5 Mpc). Total areas of approximately 940 and
910 square degrees in these groups were scanned visually on the SRC J films to
find dwarf candidates. Redshifts were obtained by an HI survey carried out at
Parkes, with detection limits of 4 \times 10^6 \Msun and 7.8 \times 10^6 \Msun
, and 33 dwarf galaxies were successfully detected in the groups. A follow-up
optical survey (Halpha spectroscopy) detected a few more, and confirmed most of
the HI redshifts. A total of 16 and 20 dwarf galaxies are found in Sculptor and
Centaurus A, of which 6 are newly identified objects, and 5 more have newly
determined redshifts. In both groups the dwarf members show a wider spatial and
velocity distribution than the brighter members. From their radial velocities
and projected distances we estimate the crossing times of the groups, which
confirm that they are not yet virialised.Comment: 35 pages Latex (aaspp4.sty) including all tables and 7 postscript
figures. Figs 1,2,3 available at ftp://ftp.hq.eso.org/incoming/scote
Submitted to A
NGC 5084: A Massive Disk Galaxy Accreting its Satellites ?
The spectra of 34 galaxies within 20 arcmins (\sim 100 kpc) of the lenticular
galaxy NGC 5084 have been obtained using the FOCAP system on the
Anglo-Australian 3.9m telescope. Nine objects are found with projected
separations \lesssim 80 kpc and with radial velocities within \pm 630 km/s of
the parent galaxy redshift. Using various techniques, their velocity
differences and projected separations are used to estimate the mass of this S0
galaxy, which ranges from 6 \times 10^{12} M_{\odot} to 1 \times 10^{13}
M_{\odot}. With such a mass, NGC 5084 is one of the most massive disk galaxy
known, with a M/L_B \gtrsim 200 M_{\odot}/L_{\odot}. In agreement with the
models' predictions of Quinn & Goodman (1986) but contrary to the results of
Zaritsky et al (1993) obtained from their statistical sample, the properties of
the satellites' population show no evidence for the "Holmberg effect", and a
clear excess of satellites in retrograde orbits. Several signs hint that this
S0 galaxy has survived the accretion of several satellites.Comment: 20 pages Latex (aasms4.sty) including all tables and 4 postscript
figures. AJ in Pres
Recognition and repair of trans-syn II cyclobutane thymine dimer by mammalian excision nuclease indicate that the affinities of damage sensors do not dictate the repair efficiency
The trans-syn cyclobutane pyrimidine dimer is a minor, but biologically significant ultraviolet photoproduct that is produced primarily in single-strand DNA. The only known repair system for this lesion is nucleotide excision repair. In this study I investigated the recognition and repair of the trans-syn cyclobutane thymine dimer by mammalian excision nuclease. I find that the trans-syn cyclobutane thymine dimer is recognized by RPA, XPA, and XPC damage sensor proteins with high specificity comparable to that of the [6-4] photoproduct; however, this lesion is excised by the mammalian excision nuclease with efficiency comparable to that of the poorly recognized cis-syn cyclobutane pyrimidine dimer. These data suggest that kinetic factors, after the initial damage recognition step, play a major role in the overall catalytic proficiency of the mammalian excision nuclease
Finding Humanity in Design
The Calgary Board of Education’s Design the Shift was a radical step away from typical professional development opportunities. It was a year-long collaboration designed for educators to provoke a shift in practice by redefining curriculum through design. Our definition of design evolved from a linear business model to a much more generous movement. As designers of learning, the participants took up “what really [mattered] to them”, with design becoming an intersection of creativity, place, and community (Chambers, 1998, p. 17). We created opportunities for participants to charge up against an experience, causing them to make, unmake, and remake the curriculum of their classrooms. All experiences inspired the participants to stop, notice, listen and awaken, drawing on Maxine Greene’s (1977) wide-awakeness philosophy
Nutrition Students’ Perception of The Role of the SLPs in Treating People Living with HIV/AIDS
This project explores nutrition students’ perceptions of SLPs\u27 and Nutritionists’ role in healthcare needs of PLWHA through survey research. The results will describe participants’ perceptions of the SLPs\u27 and Nutritionists’ roles in the healthcare needs of PLWHA. Recommendations are made regarding interprofessional training curricula for SLP and Nutrition students
Unmasking “Mean Girls” Panel
This featured panel discusses the prevalence of female juvenile violence; reported incidences of this violence; factors associated with violent behavior; and implications for families, schools, and communities for ending violent schoolgirl behavior
Lighting the Way: A Report for Philanthropy on the Power and Promise of Feminist Movements
Feminist movements are powerhouses for social change, but they are under-resourced, undervalued, and grossly underestimated. New Bridgespan research with Shake the Table shares five recommendations for funders on how to find and fund feminist movements, and calls on philanthropy to invest an additional $6 billion in them by 2026
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