Facilitating Keyboard Use While Wearing a Head-Mounted Display

Virtual reality (VR) headsets are becoming more common and will require evolving input mechanisms to support a growing range of applications. Because VR devices require users to wear head-mounted displays, there are accomodations that must be made in order to support specific input devices. One such device, a keyboard, serves as a useful tool for text entry. Many users will require assistance towards using a keyboard when wearing a head-mounted display. Developers have explored new mechanisms to overcome the challenges of text-entry for virtual reality. Several games have toyed with the idea of using motion controllers to provide a text entry mechanism, however few investigations have made on how to assist users in using a physical keyboard while wearing a head-mounted display. As an alternative to controller based text input, I propose that a software tool could facilitate the use of a physical keyboard in virtual reality. Using computer vision, a user€™s hands could be projected into the virtual world. With the ability to see the location of their hands relative to the keyboard, users will be able to type despite the obstruction caused by the head-mounted display (HMD). The viability of this approach was tested and the tool released as a plugin for the Unity development platform. The potential uses for the plugin go beyond text entry, and the project can be expanded to include many physical input devices

High-dispersion absorption-line spectroscopy of AE Aqr

High-dispersion time-resolved spectroscopy of the unique magnetic cataclysmic variable AE Aqr is presented. A radial velocity analysis of the absorption lines yields K2= 168.7 ± 1 km s−1. Substantial deviations of the radial velocity curve from a sinusoid are interpreted in terms of intensity variations over the secondary star's surface. A complex rotational velocity curve as a function of orbital phase is detected which has a modulation frequency of twice the orbital frequency, leading to an estimate of the binary inclination angle that is close to 70°. The minimum and maximum rotational velocities are used to indirectly derive a mass ratio of q= 0.6 and a radial velocity semi-amplitude of the white dwarf of K1= 101 ± 3 km s−1. We present an atmospheric temperature indicator, based on the absorption-line ratio of Fe I and Cr I lines, whose variation indicates that the secondary star varies from K0 to K4 as a function of orbital phase. The ephemeris of the system has been revised, using more than 1000 radial velocity measurements, published over nearly five decades. From the derived radial velocity semi-amplitudes and the estimated inclination angle, we calculate that the masses of the stars are M1= 0.63 ± 0.05 M⊙; M2= 0.37 ± 0.04 M⊙, and their separation is a= 2.33 ± 0.02 R⊙. Our analysis indicates the presence of a late-type star whose radius is larger, by a factor of nearly 2, than the radius of a normal main-sequence star of the same mass. Finally, we discuss the possibility that the measured variations in the rotational velocity, temperature and spectral type of the secondary star as functions of orbital phase may, like the radial velocity variations, be attributable to regions of enhanced absorption on the star's surface

The spin-orbit alignment of the transiting exoplanet WASP-3b from Rossiter-McLaughlin observations

We present an observation of the Rossiter-McLaughlin effect for the planetary system WASP-3. Radial velocity measurements were made during transit using the SOPHIE spectrograph at the 1.93m telescope at Haute-Provence Observatory. The shape of the effect shows that the sky-projected angle between the stellar rotation axis and planetary orbital axis (lambda) is small and consistent with zero within 2 sigma; lambda = 15 +10/-9 deg. WASP-3b joins the ~two-thirds of planets with measured spin-orbit angles that are well aligned and are thought to have undergone a dynamically-gentle migration process such as planet-disc interactions. We find a systematic effect which leads to an anomalously high determination of the projected stellar rotational velocity (vsini = 19.6 +2.2/-2.1 km/s) compared to the value found from spectroscopic line broadening (vsini = 13.4 +/- 1.5 km/s). This is thought to be caused by a discrepancy in the assumptions made in the extraction and modelling of the data. Using a model developed by Hirano et al. (2009) designed to address this issue, we find vsini to be consistent with the value obtained from spectroscopic broadening measurements (vsini = 15.7 +1.4/-1.3 km/s).Comment: 7 pages, 3 figures, published in MNRAS 405 (2010) 1867-1872. Update includes discussion on differential rotaation and correction of typo

The Origins and Evolutionary Status of B Stars Found Far From the Galactic Plane II: Kinematics and Full Sample Analysis

This paper continues the analysis of faint high latitude B stars from Martin (2004). Here we analyze the kinematics of the stars and combine them with the abundance information from the first paper to classify each one. The sample contains 31 Population I runaways, fifteen old evolved stars (including five BHB stars, three post-HB stars, a pulsating helium dwarf, and six stars of ambiguous classification), one F-dwarf, and two stars which do not easily fit in one of the other categories. No star in the sample unambiguously shows the characteristics of a young massive star formed in situ in the halo. The two unclassified stars are probably extreme Population I runaways. The low binary frequency and rotational velocity distribution of the Population I runaways imply that most were ejected from dense star clusters by DES (dynamic ejection scenario). However we remain puzzled by the lack of runaway Be stars. We also confirm that PB 166 and HIP 41979 are both nearby solar-metallicity BHB stars.Comment: 59 pages including 14 Figures, 12 Tables; Accepted for publication in the Astronomical Journa

Heaviness, health and happiness: a cross-sectional study of 163 066 UK Biobank participants

<b>Background</b><p></p> Obesity is known to increase the risk of many diseases and reduce overall quality of life. This study examines the relationship with self-reported health (SRH) and happiness.<p></p> <b>Methods</b> <p></p>We conducted a cross-sectional study of the 163 066 UK Biobank participants who completed the happiness rating. The association between adiposity and SRH and happiness was examined using logistic regression. SRH was defined as good (excellent, good), or poor (fair, poor). Self-reported happiness was defined as happy (extremely, very, moderately) or unhappy (moderately, very, extremely). <p></p> <b>Results</b> <p></p>Poor health was reported by 44 457 (27.3%) participants. The adjusted ORs for poor health were 3.86, 2.92, 2.60 and 6.41 for the highest, compared with lowest, deciles of Body Mass Index, waist circumference, waist to hip ratio and body fat percent, respectively. The associations were stronger in men (p<0.001). Overall, 7511 (4.6%) participants felt unhappy, and only class III obese participants were more likely to feel unhappy (adjusted OR 1.33, 95% CI 1.15 to 1.53, p<0.001) but the associations differed by sex (p<0.001). Among women, there was a significant association between unhappiness and all levels of obesity. By contrast, only class III obese men had significantly increased risk and overweight and class I obese men were less likely to be unhappy. <p></p> <b>Conclusions</b><p></p>Obesity impacts adversely on happiness as well as health, but the association with unhappiness disappeared after adjustment for self-reported health, indicating this may be mediated by health. Compared with obese men, obese women are less likely to report poor health, but more likely to feel unhappy. <p></p&gt

Foot pain and foot health in an educated population of adults: results from the Glasgow Caledonian University Alumni Foot Health Survey

Abstract Background Foot pain is common amongst the general population and impacts negatively on physical function and quality of life. Associations between personal health characteristics, lifestyle/behaviour factors and foot pain have been studied; however, the role of wider determinants of health on foot pain have received relatively little attention. Objectives of this study are i) to describe foot pain and foot health characteristics in an educated population of adults; ii) to explore associations between moderate-to-severe foot pain and a variety of factors including gender, age, medical conditions/co-morbidity/multi-morbidity, key indicators of general health, foot pathologies, and social determinants of health; and iii) to evaluate associations between moderate-to-severe foot pain and foot function, foot health and health-related quality-of-life. Methods Between February and March 2018, Glasgow Caledonian University Alumni with a working email address were invited to participate in the cross-sectional electronic survey (anonymously) by email via the Glasgow Caledonian University Alumni Office. The survey was constructed using the REDCap secure web online survey application and sought information on presence/absence of moderate-to-severe foot pain, patient characteristics (age, body mass index, socioeconomic status, occupation class, comorbidities, and foot pathologies). Prevalence data were expressed as absolute frequencies and percentages. Multivariate logistic and linear regressions were undertaken to identify associations 1) between independent variables and moderate-to-severe foot pain, and 2) between moderate-to-severe foot pain and foot function, foot health and health-related quality of life. Results Of 50,228 invitations distributed, there were 7707 unique views and 593 valid completions (median age [inter-quartile range] 42 [31–52], 67.3% female) of the survey (7.7% response rate). The sample was comprised predominantly of white Scottish/British (89.4%) working age adults (95%), the majority of whom were overweight or obese (57.9%), and in either full-time or part-time employment (82.5%) as professionals (72.5%). Over two-thirds (68.5%) of the sample were classified in the highest 6 deciles (most affluent) of social deprivation. Moderate-to-severe foot pain affected 236/593 respondents (39.8%). High body mass index, presence of bunions, back pain, rheumatoid arthritis, hip pain and lower occupation class were included in the final multivariate model and all were significantly and independently associated with moderate-to-severe foot pain (p < 0.05), except for rheumatoid arthritis (p = 0.057). Moderate-to-severe foot pain was significantly and independently associated lower foot function, foot health and health-related quality of life scores following adjustment for age, gender and body mass index (p < 0.05). Conclusions Moderate-to-severe foot pain was highly prevalent in a university-educated population and was independently associated with female gender, high body mass index, bunions, back pain, hip pain and lower occupational class. Presence of moderate-to-severe foot pain was associated with worse scores for foot function, foot health and health-related quality-of-life. Education attainment does not appear to be protective against moderate-to-severe foot pain

Tracking vegetation phenology across diverse North American biomes using PhenoCam imagery

Vegetation phenology controls the seasonality of many ecosystem processes, as well as numerous biosphere-atmosphere feedbacks. Phenology is also highly sensitive to climate change and variability. Here we present a series of datasets, together consisting of almost 750 years of observations, characterizing vegetation phenology in diverse ecosystems across North America. Our data are derived from conventional, visible-wavelength, automated digital camera imagery collected through the PhenoCam network. For each archived image, we extracted RGB (red, green, blue) colour channel information, with means and other statistics calculated across a region-of-interest (ROI) delineating a specific vegetation type. From the high-frequency (typically, 30 min) imagery, we derived time series characterizing vegetation colour, including “canopy greenness”, processed to 1- and 3-day intervals. For ecosystems with one or more annual cycles of vegetation activity, we provide estimates, with uncertainties, for the start of the “greenness rising” and end of the “greenness falling” stages. The database can be used for phenological model validation and development, evaluation of satellite remote sensing data products, benchmarking earth system models, and studies of climate change impacts on terrestrial ecosystems

HLA Genes, Islet Autoantibodies and Residual C-Peptide at the Clinical Onset of Type 1 Diabetes Mellitus and the Risk of Retinopathy 15 Years Later

HLA genes, islet autoantibodies and residual C-peptide were studied to determine the independent association of each exposure with diabetic retinopathy (DR), 15 years after the clinical onset of type 1 diabetes in 15-34 year old individuals.The cohort was identified in 1992 and 1993 by the Diabetes Incidence Study in Sweden (DISS), which investigates incident cases of diabetes for patients between 15 and 34 years of age. Blood samples at diagnosis were analyzed to determine HLA genotype, islet autoantibodies and serum C-peptide. In 2009, fundus photographs were obtained from patient records. Study measures were supplemented with data from the Swedish National Diabetes Registry.The prevalence of DR was 60.2% (148/246). Autoantibodies against the 65 kD isoform of glutamate decarboxylase (GADA) at the onset of clinical diabetes increased the risk of DR 15 years later, relative risk 1.12 for each 100 WHO units/ml, [95% CI 1.02 to 1.23]. This equates to risk estimates of 1.27, [95% CI 1.04 to 1.62] and 1.43, [95% CI 1.06 to 1.94] for participants in the highest 25(th) (GADA>233 WHO units/ml) and 5(th) percentile (GADA>319 WHO units/ml) of GADA, respectively. These were adjusted for duration of diabetes, HbA(1c), treated hypertension, sex, age at diagnosis, HLA and C-peptide. Islet cell autoantibodies, insulinoma-antigen 2 autoantibodies, residual C-peptide and the type 1 diabetes associated haplotypes DQ2, DQ8 and DQ6 were not associated with DR.Increased levels of GADA at the onset of type 1 diabetes were associated with DR 15 years later. These results, if confirmed, could provide additional insights into the pathogenesis of the most common microvascular complication of diabetes and lead to better risk stratification for both patient screenings and DR treatment trials

Collisional and Radiative Processes in Optically Thin Plasmas

Most of our knowledge of the physical processes in distant plasmas is obtained through measurement of the radiation they produce. Here we provide an overview of the main collisional and radiative processes and examples of diagnostics relevant to the microphysical processes in the plasma. Many analyses assume a time-steady plasma with ion populations in equilibrium with the local temperature and Maxwellian distributions of particle velocities, but these assumptions are easily violated in many cases. We consider these departures from equilibrium and possible diagnostics in detail