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Mental health in UK Biobank - development, implementation and results from an online questionnaire completed by 157 366 participants: a reanalysis
Background
UK Biobank is a well-characterised cohort of over 500 000 participants including genetics, environmental data and imaging. An online mental health questionnaire was designed for UK Biobank participants to expand its potential.
Aims
Describe the development, implementation and results of this questionnaire.
Method
An expert working group designed the questionnaire, using established measures where possible, and consulting a patient group. Operational criteria were agreed for defining likely disorder and risk states, including lifetime depression, mania/hypomania, generalised anxiety disorder, unusual experiences and self-harm, and current post-traumatic stress and hazardous/harmful alcohol use.
Results
A total of 157 366 completed online questionnaires were available by August 2017. Participants were aged 45–82 (53% were ≥65 years) and 57% women. Comparison of self-reported diagnosed mental disorder with a contemporary study shows a similar prevalence, despite respondents being of higher average socioeconomic status. Lifetime depression was a common finding, with 24% (37 434) of participants meeting criteria and current hazardous/harmful alcohol use criteria were met by 21% (32 602), whereas other criteria were met by less than 8% of the participants. There was extensive comorbidity among the syndromes. Mental disorders were associated with a high neuroticism score, adverse life events and long-term illness; addiction and bipolar affective disorder in particular were associated with measures of deprivation.
Conclusions
The UK Biobank questionnaire represents a very large mental health survey in itself, and the results presented here show high face validity, although caution is needed because of selection bias. Built into UK Biobank, these data intersect with other health data to offer unparalleled potential for crosscutting biomedical research involving mental health
Charge and spin distributions in GaMnAs/GaAs Ferromagnetic Multilayers
A self-consistent electronic structure calculation based on the
Luttinger-Kohn model is performed on GaMnAs/GaAs multilayers. The Diluted
Magnetic Semiconductor layers are assumed to be metallic and ferromagnetic. The
high Mn concentration (considered as 5% in our calculation) makes it possible
to assume the density of magnetic moments as a continuous distribution, when
treating the magnetic interaction between holes and the localized moment on the
Mn(++) sites. Our calculation shows the distribution of heavy holes and light
holes in the structure. A strong spin-polarization is observed, and the charge
is concentrated mostly on the GaMnAs layers, due to heavy and light holes with
their total angular momentum aligned anti-parallel to the average
magnetization. The charge and spin distributions are analyzed in terms of their
dependence on the number of multilayers, the widths of the GaMnAs and GaAs
layers, and the width of lateral GaAs layers at the borders of the structure.Comment: 12 pages,7 figure
Exercise therapy in adults with serious mental illness: a systematic review and meta-analysis
Background: Individuals with serious mental illness are at a higher risk of physical ill health. Mortality rates are at least twice those of the general population with higher levels of cardiovascular disease, metabolic disease, diabetes, and respiratory illness. Although genetics may have a role in the physical health problems of these patients, lifestyle and environmental factors such as levels of smoking, obesity, poor diet, and low levels of physical activity also play a prominent part.<p></p>
Objective: To conduct a systematic review and meta-analysis of randomised controlled trials comparing the effect of exercise interventions on individuals with serious mental illness.<p></p>
Methods: Searches were made in Ovid MEDLINE, Embase, CINAHL, PsycINFO, Biological Abstracts on Ovid, and The Cochrane Library (January 2009, repeated January 2013) through to February 2013.<p></p>
Results: Eight RCTs were identified in the systematic search. Six compared exercise versus usual care. One study assessed the effect of a cycling programme versus muscle strengthening and toning exercises. The final study compared the effect of adding specific exercise advice and motivational skills to a simple walking programme. Exercise programmes were noted by their heterogeneity in terms of the type of exercise intervention, setting, and outcome measures. The review found that exercise improved levels of exercise activity (n=13, standard mean difference [SMD] 1.81, CI 0.44 to 3.18, p = 0.01). No beneficial effect was found on negative (n = 84, SMD = -0.54, CI -1.79 to 0.71, p = 0.40) or positive symptoms of schizophrenia (n = 84, SMD = -1.66, CI -3.78 to 0.45, p = 0.12). No change was found on body mass index compared with usual care (n= 151, SMD = -0.24, CI -0.56 to 0.08, p = 0.14), or body weight (n = 77, SMD = 0.13, CI -0.32 to 0.58, p = 0.57).
No beneficial effect was found on anxiety and depressive symptoms (n = 94, SMD = -0.26, CI -0.91 to 0.39, p = 0.43), or quality of life in respect of physical and mental domains. One RCT measured the effect of exercise on exercise intensity, attendance, and persistence at a programme. No significant effect was found on these measures.<p></p>
Conclusions: This systematic review showed that exercise therapies can lead to a modest increase in levels of exercise activity but overall there was no noticeable change for symptoms of mental health, body mass index, and body weight.<p></p>
Quantum Information Processing with Ferroelectrically Coupled Quantum Dots
I describe a proposal to construct a quantum information processor using
ferroelectrically coupled Ge/Si quantum dots. The spin of single electrons form
the fundamental qubits. Small (<10 nm diameter) Ge quantum dots are optically
excited to create spin polarized electrons in Si. The static polarization of an
epitaxial ferroelectric thin film confines electrons laterally in the
semiconductor; spin interactions between nearest neighbor electrons are
mediated by the nonlinear process of optical rectification. Single qubit
operations are achieved through "g-factor engineering" in the Ge/Si structures;
spin-spin interactions occur through Heisenberg exchange, controlled by
ferroelectric gates. A method for reading out the final state, while required
for quantum computing, is not described; electronic approaches involving single
electron transistors may prove fruitful in satisfying this requirement.Comment: 10 pages, 3 figure
A convenient band-gap interpolation technique and an improved band line-up model for InGaAlAs on InP
The band-gap energy and the band line-up of InGaAlAs quaternary compound material on InP are essential information for the theoretical study of physical properties and the design of optoelectronics devices operating in the long-wavelength communication window. The band-gap interpolation of In1-x-y Ga (x) Al (y) As on InP is known to be a challenging task due to the observed discrepancy of experimental results arising from the bowing effect. Besides, the band line-up results of In1-x-y Ga (x) Al (y) As on InP based on previously reported models have limited success by far. In this work, we propose an interpolation solution using the single-variable surface bowing estimation interpolation method for the fitting of experimentally measured In1-x-y Ga (x) Al (y) As band-gap data with various degree of bowing using the same set of input parameters. The suggested solution provides an easier and more physically interpretable way to determine not only lattice matched, but also strained band-gap energy of In1-x-y Ga (x) Al (y) As on InP based on the experimental results. Interpolated results from this convenient method show a more favourable match to multiple independent experiment data sets measured under different temperature conditions as compared to those obtained from the commonly used weighted-sum approach. On top of that, extended framework of the model-solid theory for the band line-up of In1-x-y Ga (x) Al (y) As/InP heterostructure is proposed. Our model-solid theory band line-up result using the proposed extended framework has shown an improved accuracy over those without the extension. In contrast to some previously reported works, it is worth noting that the band line-up result based on our proposed extended model-solid theory has also shown to be more accurate than those given by Harrison's mode
Intergroup helping in response to separatism
Despite its prevalence and widespread media coverage, separatism as a phenomenon is barely covered in psychological investigations, and the majority's response to separatism has been completely ignored. We present two studies in which we investigated the notion that separatist movements threaten the continuation of the national identity, as well as the nation's economic position. Moreover, we hypothesized and found that members of the majority group respond to continuation threat by supporting government measures to help the separatist group. Javanese students who were induced to believe that existing separatist movements in West Papua (Study 1, N = 322) or Aceh (Study 2, N = 180) were currently increasing their efforts to gain independence were more willing to support these groups than participants who believed these movements were dormant. Moreover, this effect was mediated by continuation threat but not economic threat. These results demonstrate the possibility of a peaceful response to separatism threat. © 2013 by the Society for Personality and Social Psychology, Inc
Preliminary archaeoentomological analyses of permafrost-preserved cultural layers from the pre-contact Yup’ik Eskimo site of Nunalleq, Alaska : implications, potential and methodological considerations
Acknowledgements Site excavation and samples collection were conducted by archaeologists from the University of Aberdeen, with the help of archaeologists and student excavators from the University of Aberdeen University of Alaska Fairbanks and Bryn Mawr College, Kuskokwim Campus, College of Rural Alaska and residents of Quinhagak and Mekoryuk. This study is funded through AHRC grant to the project ‘Understanding Cultural Resilience and Climate Change on the Bering Sea through Yup’ik Ecological Knowledge, Lifeways, Learning and Archaeology’ to Rick Knecht, Kate Britton and Charlotta Hillderal (University of Aberdeen; AH/K006029/1). Thanks are due to Qanirtuuq Inc. and Quinhagak, Alaska for sampling permissions and to entomologists working at the CNC in Ottawa for allowing access to reference collections of beetles, lice and fleas. Yves Bousquet, Ales Smetana and Anthony E. Davies are specially acknowledged for their help with the identification of coleopteran specimens. Finally, we would also like to thank Scott Elias for useful comments on the original manuscript.Peer reviewedPublisher PD
Avalanche amplification of a single exciton in a semiconductor nanowire
Interfacing single photons and electrons is a crucial ingredient for sharing
quantum information between remote solid-state qubits. Semiconductor nanowires
offer the unique possibility to combine optical quantum dots with avalanche
photodiodes, thus enabling the conversion of an incoming single photon into a
macroscopic current for efficient electrical detection. Currently, millions of
excitation events are required to perform electrical read-out of an exciton
qubit state. Here we demonstrate multiplication of carriers from only a single
exciton generated in a quantum dot after tunneling into a nanowire avalanche
photodiode. Due to the large amplification of both electrons and holes (>
10^4), we reduce by four orders of magnitude the number of excitation events
required to electrically detect a single exciton generated in a quantum dot.
This work represents a significant step towards single-shot electrical read-out
and offers a new functionality for on-chip quantum information circuits
Multi-level evidence of an allelic hierarchy of USH2A variants in hearing, auditory processing and speech/language outcomes.
Language development builds upon a complex network of interacting subservient systems. It therefore follows that variations in, and subclinical disruptions of, these systems may have secondary effects on emergent language. In this paper, we consider the relationship between genetic variants, hearing, auditory processing and language development. We employ whole genome sequencing in a discovery family to target association and gene x environment interaction analyses in two large population cohorts; the Avon Longitudinal Study of Parents and Children (ALSPAC) and UK10K. These investigations indicate that USH2A variants are associated with altered low-frequency sound perception which, in turn, increases the risk of developmental language disorder. We further show that Ush2a heterozygote mice have low-level hearing impairments, persistent higher-order acoustic processing deficits and altered vocalizations. These findings provide new insights into the complexity of genetic mechanisms serving language development and disorders and the relationships between developmental auditory and neural systems
Linear and Second-order Optical Response of the III-V Mono-layer Superlattices
We report the first fully self-consistent calculations of the nonlinear
optical properties of superlattices. The materials investigated are mono-layer
superlattices with GaP grown on the the top of InP, AlP and GaAs (110)
substrates. We use the full-potential linearized augmented plane wave method
within the generalized gradient approximation to obtain the frequency dependent
dielectric tensor and the second-harmonic-generation susceptibility. The effect
of lattice relaxations on the linear optical properties are studied. Our
calculations show that the major anisotropy in the optical properties is the
result of strain in GaP. This anisotropy is maximum for the superlattice with
maximum lattice mismatch between the constituent materials. In order to
differentiate the superlattice features from the bulk-like transitions an
improvement over the existing effective medium model is proposed. The
superlattice features are found to be more pronounced for the second-order than
the linear optical response indicating the need for full supercell calculations
in determining the correct second-order response.Comment: 9 pages, 4 figures, submitted to Phy. Rev.
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