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UK Biobank is a well-characterised cohort of over 500 000 participants that offers unique opportunities to investigate multiple diseases and risk factors.
An online mental health questionnaire completed by UK Biobank participants was expected to expand the potential for research into mental disorders.
An expert working group designed the questionnaire, using established measures where possible, and consulting with a patient group regarding acceptability. Case definitions were defined using operational criteria for lifetime depression, mania, anxiety disorder, psychotic-like experiences and self-harm, as well as current post-traumatic stress and alcohol use disorders.
157 366 completed online questionnaires were available by August 2017. Comparison of self-reported diagnosed mental disorder with a contemporary study shows a similar prevalence, despite respondents being of higher average socioeconomic status than the general population across a range of indicators. Thirty-five per cent (55 750) of participants had at least one defined syndrome, of which lifetime depression was the most common at 24% (37 434). There was extensive comorbidity among the syndromes. Mental disorders were associated with high neuroticism score, adverse life events and long-term illness; addiction and bipolar affective disorder in particular were associated with measures of deprivation.
The questionnaire represents a very large mental health survey in itself, and the results presented here show high face validity, although caution is needed owing to selection bias. Built into UK Biobank, these data intersect with other health data to offer unparalleled potential for crosscutting biomedical research involving mental health.
Declaration of interest
G.B. received grants from the National Institute for Health Research during the study; and support from Illumina Ltd. and the European Commission outside the submitted work. B.C. received grants from the Scottish Executive Chief Scientist Office and from The Dr Mortimer and Theresa Sackler Foundation during the study. C.S. received grants from the Medical Research Council and Wellcome Trust during the study, and is the Chief Scientist for UK Biobank. M.H. received grants from the Innovative Medicines Initiative via the RADAR-CNS programme and personal fees as an expert witness outside the submitted work.
Insomnia treatment using an internet-based cognitive–behavioural therapy
for insomnia (CBT-I) program reduces depression symptoms, anxiety
symptoms and suicidal ideation. However, the speed, longevity and
consistency of these effects are unknown.
To test the following: whether the efficacy of online CBT-I was sustained
over 18 months; how rapidly the effects of CBT-I emerged; evidence for
distinct trajectories of change in depressive symptoms; and predictors of
A randomised controlled trial compared the 6-week Sleep Healthy Using the
Internet (SHUTi) CBT-I program to an attention control program. Adults
(N=1149) with clinical insomnia and subclinical
depression symptoms were recruited online from the Australian
Depression, anxiety and insomnia decreased significantly by week 4 of the
intervention period and remained significantly lower relative to control
for >18 months (between-group Cohen's d=0.63, 0.47,
0.55, respectively, at 18 months). Effects on suicidal ideation were only
short term. Two depression trajectories were identified using growth
mixture models: improving (95%) and stable/deteriorating (5%) symptoms.
More severe baseline depression, younger age and limited comfort with the
internet were associated with reduced odds of improvement.
Online CBT-I produced rapid and long-term symptom reduction in people
with subclinical depressive symptoms, although the initial effect on
suicidal ideation was not sustained.
A common problem in producing interferometer maps of objects with structure on the scale-size of the primary beam is the acquisition of UV data corresponding to telescope spacings of less than one telescope diameter. One technique for solving this “short-spacing” problem is to divide the aperture of one of the telescopes into smaller sub-apertures and measuring the visibilities between these sub-apertures. This technique is being tested using the Owens Valley Millimeter Interferometer.
Faint dwarf galaxies such as those found around the Milky Way (MW) display the largest known dynamical mass-to-light ratios (up to several 100s M⊙/L⊙). However, tidal interaction with the MW may impact the dynamical equilibrium in the outer parts of some of these objects, and partly affect the derived dynamical M/L. Assessing this is crucial for the study of the dark matter content of these galaxies. A clear sign of ongoing tidal disturbance would be the presence of tidal tails. These are expected to be low surface brightness features, hence difficult to detect from star counts in systems where contamination is also present, e.g. from foreground MW stars. At present we have searched for these sorts of tidal features in the Sextans dwarf spheroidal galaxy (dSph), by adopting the Matched Filter Method (e.g. Rockosi et al. 2002), a very efficient technique to decontaminate stellar density maps with a high ratio of contamination versus source density (dwarf galaxies outer regions or ultra faint dwarf galaxies). We also calculate structural parameters from the position of stars without requiring spatial binning (Richardson et al. 2011), through a Bayesian MCMC (Foreman-Mackey et al. 2013).
The use of underground geological repositories, such as in radioactive waste disposal (RWD) and in carbon capture (widely known as Carbon Capture and Storage; CCS), constitutes a key environmental priority for the 21st century. Based on the identification of key scientific questions relating to the geophysics, geochemistry and geobiology of geodisposal of wastes, this paper describes the possibility of technology transfer from high-technology areas of the space exploration sector, including astrobiology, planetary sciences, astronomy, and also particle and nuclear physics, into geodisposal. Synergies exist between high technology used in the space sector and in the characterization of underground environments such as repositories, because of common objectives with respect to instrument miniaturization, low power requirements, durability under extreme conditions (in temperature and mechanical loads) and operation in remote or otherwise difficult to access environments.
The safe operating area (SOA) of InGaP/GaAs heterojunction bipolar transistors has been studied using two-dimensional Technology Computer-Aided Design (TCAD) tool. Comprehensive physical models, including hydrodynamic transport-based impact ionization and self-heating models were implemented. The simulations for two DC modes (constant Ib and Vb modes) captured all the SOA features observed in measurements and some failure mechanisms were revealed for the first time by TCAD simulations. The simulated results are also in agreement with analytical modeling. The simulation not only gives us insight to the detailed failure mechanisms, but also provides guidance for the design of devices with better ruggedness and improved SOA performances.
This article concerns application of cathodoluminescence (CL) spectroscopy to volcanic quartz and its utility in assessing variation in trace quantities of Ti within individual crystals. CL spectroscopy provides useful details of intragrain compositional variability and structure but generally limited quantitative information on element abundances. Microbeam analysis can provide such information but is time-consuming and costly, particularly if large numbers of analyses are required. To maximize advantages of both approaches, natural and synthetic quartz crystals were studied using high-resolution hyperspectral CL imaging (1.2–5.0 eV range) combined with analysis via laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Spectral intensities can be deconvolved into three principal contributions (1.93, 2.19, and 2.72 eV), for which intensity of the latter peak was found to correlate directly with Ti concentration. Quantitative maps of Ti variation can be produced by calibration of the CL spectral data against relatively few analytical points. Such maps provide useful information concerning intragrain zoning or heterogeneity of Ti contents with the sensitivity of LA-ICPMS analysis and spatial resolution of electron microprobe analysis.
The last part of SpS5 dealt with the circumstellar environment. Structures are indeed found around several types of massive stars, such as blue and red supergiants, as well as WRs and LBVs. As shown in the last years, the potential of IR for their study is twofold: first, IR can help discover many previously unknown nebulae, leading to the identification of new massive stars as their progenitors; second, IR can help characterize the nebular features. Current and new IR facilities thus pave the way to a better understanding of the feedback from massive stars.
In this paper we are presenting the results of silicon nano-trap memory fabricated by implanting high dose silicon into gate oxide of thickness 30 nm. The gate oxide was grown by dry oxidation. Capacitance versus voltage characteristics of MOS (metal oxide silicon) structures with silicon implanted samples annealed in nitrogen environment at a temperature of 950 °C show a memory window depending on the applied DC bias voltage. A memory window of 3V was obtained for an applied bias voltage of ± 10V. Annealing of the MOS structures in a furnace at a temperature of 800 °C for 30 minutes in oxygen resulted in complete loss or collapse of the memory window. Annealing the samples rapid thermally in oxygen environment at 800 oC for 30 seconds, resulted in a memory window of about 2 Volts for an applied voltage of ± 14V.
Zirconium carbide is an attractive ceramic material due to its unique properties such as high melting point, good thermal conductivity, and chemical resistance. The controlled preparation of zirconium carbide films of superstoichiometric, stoichiometric, and substoichiometric compositions has been achieved utilizing zirconium tetrachloride and methane precursor gases in an atmospheric pressure high temperature chemical vapor deposition system. Laminar and equiaxial microcrystalline morphologies were obtained for superstoichiometric and substoichiometric zirconium carbide; respectively, allowing cursory metallographic identification of composition. Observed reductions in film density associated with zirconium carbide films that contain additional free carbon or excess zirconium are reported. These changes in film density were found to be consistent with compositional changes. An apparently linear relationship (correlation of 0.99) between methane flow in this chemical vapor deposition system and zirconium carbide stoichiometry in the substoichiometric range deposited above ZrC0.61 has been observed.
Owing to its photoluminescent properties and high surface area, porous silicon (por-Si) has shown great potential toward a myriad of applications including optoelectronics, chemical sensors, biocomposite materials, and medical implants. However, the native hydride-termination is only metastable with respect to surface oxidation under ambient conditions. Por-Si samples oxidize and degrade even more quickly when exposed to saline aqueous environments. Borrowing from solution phase synthetic methods, a selection of hydrosilylation reactions has been recently reported for functionalizing organic groups onto oxide-free, hydride-terminated porous silicon surfaces. Monolayers, bound through direct silicon-carbon bonds, are produced via thermal, microwave, Lewis acid, and carbocation mediated pathways. All of these wet, benchtop methods result in the formation of stable monolayers which protect the underlying silicon surface from ambient oxidation and chemical attack. However, no direct comparison of monolayer stability resulting from these diverse mechanisms has been reported. A variety of alkyl monolayers were prepared on porous silicon using the diverse hydrosilylation routes describe above and then immersed into a sequence of simulated gastric and intestinal fluids to replicate the conditions of potential por-Si biosensors or medicinal delivery systems in the human gastrointestinal tract. Degradation of the organic monolayers and oxidation of the underlying por-Si surfaces were monitored using both qualitative and semiquantitative transmission mode Fourier transform infrared spectroscopy (FTIR). Our initial results indicate that methods employing chemical catalysts often incorporate these species within the monolayer as defects, producing less robust surfaces compared to catalyst-free reactions. Regardless, monolayer protected por-Si samples demonstrated superior durability as opposed to the unfunctionalized controls.