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Associations between employment status and mental health are well recognised, but evidence is sparse on the relationship between paid employment and mental health in the years running up to statutory retirement ages using robust mental health measures. In addition, there has been no investigation into the stability over time in this relationship: an important consideration if survey findings are used to inform future policy. The aim of this study is to investigate the association between employment status and common mental disorder (CMD) in 50–64-year old residents in England and its stability over time, taking advantage of three national mental health surveys carried out over a 14-year period.
Data were analysed from the British National Surveys of Psychiatric Morbidity of 1993, 2000 and 2007. Paid employment status was the primary exposure of interest and CMD the primary outcome – both ascertained identically in all three surveys (CMD from the revised Clinical Interview Schedule). Multivariable logistic regression models were used.
The prevalence of CMD was higher in people not in paid employment across all survey years; however, this association was only present for non-employment related to poor health as an outcome and was not apparent in those citing other reasons for non-employment. Odds ratios for the association between non-employment due to ill health and CMD were 3.05 in 1993, 3.56 in 2000, and 2.80 in 2007, after adjustment for age, gender, marital status, education, social class, housing tenure, financial difficulties, smoking status, recent physical health consultation and activities of daily living impairment.
The prevalence of CMD was higher in people not in paid employment for health reasons, but was not associated with non-employment for other reasons. Associations had been relatively stable in strength from 1993 to 2007 in those three cross-sectional nationally representative samples.
Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self-report questionnaire measure of autistic traits. However, the ability of the AQ to predict who will go on to receive a diagnosis of ASD in adults is unclear.
We studied 476 adults, seen consecutively at a national ASD diagnostic referral service for suspected ASD. We tested AQ scores as predictors of ASD diagnosis made by expert clinicians according to International Classification of Diseases (ICD)-10 criteria, informed by the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and Autism Diagnostic Interview-Revised (ADI-R) assessments.
Of the participants, 73% received a clinical diagnosis of ASD. Self-report AQ scores did not significantly predict receipt of a diagnosis. While AQ scores provided high sensitivity of 0.77 [95% confidence interval (CI) 0.72–0.82] and positive predictive value of 0.76 (95% CI 0.70–0.80), the specificity of 0.29 (95% CI 0.20–0.38) and negative predictive value of 0.36 (95% CI 0.22–0.40) were low. Thus, 64% of those who scored below the AQ cut-off were ‘false negatives’ who did in fact have ASD. Co-morbidity data revealed that generalized anxiety disorder may ‘mimic’ ASD and inflate AQ scores, leading to false positives.
The AQ's utility for screening referrals was limited in this sample. Recommendations supporting the AQ's role in the assessment of adult ASD, e.g. UK NICE guidelines, may need to be reconsidered.
Mg, the only effective p-type dopant for nitrides, is
well-studied in thin films due to the important role the impurity plays in light
emitting diodes and high power electronics. However, there are few reports of Mg
in thick free-standing GaN substrates. Here we evaluate the material quality and
point defects in GaN grown by hydride vapor phase epitaxy (HVPE) using metallic
Mg as the doping source. The crystal quality is typical of commercially grown
HVPE substrates, and the photoluminescence measurements reveal distinctively
sharp excitonic and shallow-donor shallow-acceptor features. Secondary ion mass
spectroscopy indicates total Mg concentrations between 7x1016 and
6x1018 cm-3 in the four separate samples studied but,
more significantly, photoluminescence and electron paramagnetic resonance
spectroscopy show that the Mg is incorporated as a shallow acceptor.
Investigations describing the utilization pattern and comparing the outcome from emergency and mass casualty situations are limited by the lack of a reliable and valid patient classification system. In this study we briefly describe the use of APACHE (Acute Physiology and Chronic Health Evaluation), a physiologically based classification system for measuring severity of illness in groups of critically ill patients, as a tool in comparing outcomes of 1437 ICU admissions from eight European and five American hospitals. Because of the successful results from this pilot effort, we believe that APACHE could be used to compare the performance of hospitals in an emergency or mass casualty situation.
Si1−xGex/Si heterostructures with varying layer-thicknesses have been characterized using photoluminescence and magnetic resonance detected on photoluminescence. Three of the four samples studied exhibit sharp photoluminescence bands at different energies. For a 120 Å Si/40 Å Si1−xGex heterostructure, magnetic resonance of an electron in the Si and of a hole in the Sil. xGex layers were observed. These results indicate cross-interface, or Type II, excitonic recombination. Further, anisotropie magnetic resonance spectra indicate the presence of dangling-bonds defects in the heterostructures.
Systematic relations are shown between the parameters controlling explosive crystallization in silicon (temperature, width of a liquid zone, and gradient of melt undercooling), the kinetics of the crystallization process, the predominance of preferential growth directions, and the crystal structure observed. Three typical regions of crystallization are found: (a) cellular growth of a laminated crystalline layer controlled by the formation of high densities of twins at a nearly plane liquid/solid interface, (b) cellular-dendritic growth of crystal lamellae characterized by branching of a curved interface, and (c) formation of a diffuse “slush zone” due to random nucleation in a-Si and grain growth in the liquid zone.
Velo-cardio-facial syndrome (VCFS) is associated with deletions at chromosome 22q11, abnormalities in brain anatomy and function, and schizophrenia-like psychosis. Thus it is assumed that one or more genes within the deleted region are crucial to brain development. However, relatively little is known about how genetic variation at 22q11 affects brain structure and function. One gene on 22q11 is catechol-O-methyltransferase (COMT): an enzyme that degrades dopamine and contains a functional polymorphism (Val158Met) affecting enzyme activity. Here, we investigated the effect of COMT Val158Met polymorphism on brain anatomy and cognition in adults with VCFS.
The COMT Val158Met polymorphism was genotyped for 26 adults with VCFS on whom DNA was available. We explored its effects on regional brain volumes using hand tracing approaches; on regional grey- and white-matter density using computerized voxel-based analyses; and measures of attention, IQ, memory, executive and visuospatial function using a comprehensive neuropsychological test battery.
After corrections for multiple comparisons Val-hemizygous subjects, compared with Met-hemizygotes, had a significantly larger volume of frontal lobes. Also, Val-hemizygotes had significantly increased grey matter density in cerebellum, brainstem, and parahippocampal gyrus, and decreased white matter density in the cerebellum. No significant effects of COMT genotype on neurocognitive performance were found.
COMT genotype effects on brain anatomy in VCFS are not limited to frontal regions but also involve other structures previously implicated in VCFS. This suggests variation in COMT activity is implicated in brain development in VCFS.
Salmonella Goldcoast (SGC), an uncommon serotype in Germany, was identified in 25 isolates between 1 April and 7 May 2001. To determine the cause of the outbreak, we conducted a matched case-control study including 24 cases and 51 controls. In a multivariable regression model, only consumption of a raw fermented sausage manufactured by a local company remained significant (adjusted odds ratio 20·0, 95% confidence interval 2·7–302·5). SGC isolated from case-patients shared an indistinguishable pulsed-field gel electrophoresis pattern. A part of the produced raw fermented sausage was sold after only 4 days of fermentation. Samples from the premises and products of the company were negative for SGC. However, short-time raw fermented sausage is more likely to contain pathogens. Irradiation of raw ingredients is not accepted by German consumers, thus strict adherence to good manufacturing practices, the use of HACCP programmes as well as on-farm programmes remain crucial to reduce Salmonella.
Studies of relationships among the central nervous system (CNS), the immune system, and the endocrine system have shown that the systems interact through multiple pathways. The ‘stress’ hormones have received the greatest attention in the neuroimmunology literature, particularly cortisol and the catecholamines; sex hormones have not been studied as intensively. In this chapter we first briefly review estrogen's immunomodulatory effects. Next we discuss estrogen-related differences in cardiovascular and neuroendocrine reactivity to brief stressors. In the last section we discuss research regarding the effects of estrogen on immune reactivity to stress, and speculate about the possibility that estrogen may moderate hormonal and immunological responses to stress through alterations in sympathetic nervous system reactivity, as well as through regulation of corticotropin-releasing hormone (CRH; Vamvakopoulos & Chrousos, 1993).
Estrogen and immune function
Estrogens, androgens, and progestogens can serve as regulators of immune function; in turn, the circulating levels of these hormones can be modulated by the immune system. Many of these interactions between the immune system and gonadal steroids appear to be mediated through feedback loops in the hypothalamic–pituitary–gonadal–thymic axis, with thymic factors playing a key role (Erbach & Bahr, 1991; Grossman, 1985).
The colonization of Lactobacillus spp., enterobacteria
and facultatively anaerobic gram-positive cocci
was monitored in intestinal samples of growing broiler chicks from
24 h to 28 days of age. Rapid
bacterial growth occurred within the first week, followed by
stabilization and decline of colony
forming units (CFU). Xylanase supplementation led to significantly lower
CFU per gram of wet
weight for total presumptive enterobacteria and total gram-positive cocci
in luminal and tissue
samples in the first 3 weeks. Lactobacillus spp. colony
counts from tissue samples were higher for
animals with the xylanase-supplemented diet, but luminal CFU were not.
The composition of
dominant Lactobacillus spp. strains was different in duodenal
and jejunal tissues, but distribution of
Lactobacillus spp. colony forms was unaffected by xylanase
Enterococcus spp. displaced the dominant gram-positive cocci in
the jejunal samples. d- and l-lactic
acid and acetic acid concentrations were significantly higher in
ileal samples from the control group
on days 7 and 14, while butyric acid concentrations were higher
in the xylanase-treated group. It is
concluded that the less viscous intestinal environment caused by
the xylanase slowed proliferation
of gram-positive cocci and presumptive enterobacteria in
enzyme-supplemented animals in the first 3 weeks of life.