13,105 research outputs found

    Non-fatal self-harm in Scottish military veterans: a retrospective cohort study of 57,000 veterans and 173,000 matched non-veterans

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    Purpose: Although suicide risk in veterans has been widely studied, there is little information on the risk of non-fatal self-harm in this population. We used data from the Scottish Veterans Health Study to conduct an epidemiological analysis of self-harm in veterans, in comparison with people who have never served. Methods: We conducted a retrospective, 30-year cohort study of 56,205 veterans born 1945–1985, and 172,741 people with no record of military service, and used Cox proportional hazard models to examine the association between veteran status and cumulative risk of non-fatal self-harm, overall and stratified by birth cohort, sex and length of service. We also examined mental and physical comorbidities, and association of suicide with prior self-harm. Results: There were 1620 (2.90%) first episodes of self-harm in veterans, compared with 4212 (2.45%) in non-veterans. The difference was statistically significant overall (unadjusted HR 1.27, 95% CI 1.21–1.35, p < 0.001). The risk was highest in the oldest veterans, and in the early service leavers who failed to complete initial training (unadjusted HR 1.69, 95% CI 1.50–1.91, p < 0.001). The risk reduced with longer service and in the intermediate birth cohorts but has increased again in the youngest cohort. Conclusions: The highest risk of non-fatal self-harm was in veterans with the shortest service, especially those who did not complete training or minimum engagement, and in the oldest birth cohorts, whilst those who had served the longest were at reduced risk. The risk has increased again in the youngest veterans, and further study of this subgroup is indicated

    DURATION DEPENDENCE IN THE US BUSINESS CYCLE

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    Durland and McCurdy (1994) investigated the issue of duration dependence in US business cycle phases using a Markov regime switching approach, introduced by Hamilton (1989) and extended to the case of variable transition parameters by Filardo (1994). In Durland and McCurdy’s model duration alone was used as an explanatory of the transition probabilities. They found that recessions were duration dependent whilst expansions were not. In this paper, we explicitly incorporate the widely-accepted US business cycle phase change dates as determined by the NBER, and use a state-dependent multinomial Logit (and Probit) modelling framework. The model incorporates both duration and movements in two leading indexes - one designed to have a short lead (SLI) and the other designed to have a longer lead (LLI) - as potential explanators. We find that doing so suggests that current duration is not only a significant determinant of transition out of recessions, but that there is some evidence that it is also weakly significant in the case of expansions. Furthermore, we find that SLI has more informational content for the termination of recessions whilst LLI does so for expansions.

    Childhood IQ and risk of bipolar disorder in adulthood: prospective birth cohort study

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    Background: Intellectual ability may be an endophenotypic marker for bipolar disorder. Aims: Within a large birth cohort, we aimed to assess whether childhood IQ (including both verbal IQ (VIQ) and performance IQ (PIQ) subscales) was predictive of lifetime features of bipolar disorder assessed in young adulthood. Method: We used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a large UK birth cohort, to test for an association between measures of childhood IQ at age 8 years and lifetime manic features assessed at age 22–23 years using the Hypomania Checklist-32 (HCL-32; n=1881 individuals). An ordinary least squares linear regression model was used, with normal childhood IQ (range 90–109) as the referent group. We adjusted analyses for confounding factors, including gender, ethnicity, handedness, maternal social class at recruitment, maternal age, maternal history of depression and maternal education. Results: There was a positive association between IQ at age 8 years and lifetime manic features at age 22–23 years (Pearson's correlation coefficient 0.159 (95% CI 0.120–0.198), P>0.001). Individuals in the lowest decile of manic features had a mean full-scale IQ (FSIQ) which was almost 10 points lower than those in the highest decile of manic features: mean FSIQ 100.71 (95% CI 98.74–102.6) v. 110.14 (95% CI 107.79–112.50), P>0.001. The association between IQ and manic features was present for FSIQ, VIQ and for PIQ but was strongest for VIQ. Conclusions: A higher childhood IQ score, and high VIQ in particular, may represent a marker of risk for the later development of bipolar disorder. This finding has implications for understanding of how liability to bipolar disorder may have been selected through generations. It will also inform future genetic studies at the interface of intelligence, creativity and bipolar disorder and is relevant to the developmental trajectory of bipolar disorder. It may also improve approaches to earlier detection and treatment of bipolar disorder in adolescents and young adults

    LoCuSS: Hydrostatic Mass Measurements of the High-LXL_X Cluster Sample -- Cross-calibration of Chandra and XMM-Newton

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    We present a consistent analysis of Chandra and XMM-Newton observations of an approximately mass-selected sample of 50 galaxy clusters at 0.15<z<0.30.15<z<0.3 -- the "LoCuSS High-LXL_X Sample". We apply the same analysis methods to data from both satellites, including newly developed analytic background models that predict the spatial variation of the Chandra and XMM-Newton backgrounds to <2%<2\% and <5%<5\% precision respectively. To verify the cross-calibration of Chandra and XMM-Newton-based cluster mass measurements, we derive the mass profiles of the 21 clusters that have been observed with both satellites, extracting surface brightness and temperature profiles from identical regions of the respective datasets. We obtain consistent results for the gas and total hydrostatic cluster masses: the average ratio of Chandra- to XMM-Newton-based measurements of MgasM_{\rm gas} and MXM_X at r500r_{500} are 0.99±0.020.99\pm0.02 and 1.02±0.051.02\pm0.05, respectively with an intrinsic scatter of ∌3%\sim3\% for gas masses and ∌8%\sim8\% for hydrostatic masses. Comparison of our hydrostatic mass measurements at r500r_{500} with the latest LoCuSS weak-lensing results indicate that the data are consistent with non-thermal pressure support at this radius of ∌7%\sim7\%. We also investigate the scaling relation between our hydrostatic cluster masses and published integrated Compton parameter YsphY_{sph} measurements from the Sunyaev-Zel'dovich Array. We measure a scatter in mass at fixed YsphY_{sph} of ∌16%\sim16\% at Δ=500\Delta=500, which is consistent with theoretical predictions of ∌10−15%\sim10-15\% scatter.Comment: 21 pages, 11 figure

    Apgar score and the risk of cause specific infant mortality: a population based cohort study of 1,029,207 livebirths

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    Background&lt;p&gt;&lt;/p&gt; The Apgar score has been used worldwide as an index of early neonatal condition for more than 60 years. With advances in health-care service provision, neonatal resuscitation, and infant care, its present relevance is unclear. The aim of the study was to establish the strength of the relation between Apgar score at 5 min and the risk of neonatal and infant mortality, subdivided by specific causes.&lt;p&gt;&lt;/p&gt; Methods&lt;p&gt;&lt;/p&gt; We linked routine discharge and mortality data for all births in Scotland, UK between 1992 and 2010. We restricted our analyses to singleton livebirths, in women aged over 10 years, with a gestational age at delivery between 22 and 44 weeks, and excluded deaths due to congenital anomalies or isoimmunisation. We calculated the relative risks (RRs) of neonatal and infant death of neonates with low (0–3) and intermediate (4–6) Apgar scores at 5 min referent to neonates with normal Apgar score (7–10) using binomial log-linear modelling with adjustment for confounders. Analyses were stratified by gestational age at birth because it was a significant effect modifier. Missing covariate data were imputed.&lt;p&gt;&lt;/p&gt; Findings&lt;p&gt;&lt;/p&gt; Complete data were available for 1 029 207 eligible livebirths. Across all gestational strata, low Apgar score at 5 min was associated with an increased risk of neonatal and infant death. However, the strength of the association (adjusted RR, 95% CI referent to Apgar 7–10) was strongest at term (p&#60;0·0001). A low Apgar (0–3) was associated with an adjusted RR of 359·4 (95% CI 277·3–465·9) for early neonatal death, 30·5 (18·0–51·6) for late neonatal death, and 50·2 (42·8–59·0) for infant death. We noted similar associations of a lower magnitude for intermediate Apgar (4–6). The strongest associations were for deaths attributed to anoxia and low Apgar (0–3) for term infants (RR 961·7, 95% CI 681·3–1357·5) and preterm infants (141·7, 90·1–222·8). No association between Apgar score at 5 min and the risk of sudden infant death syndrome was noted at any gestational age (RR 0·6, 95% CI 0·1–4·6 at term; 1·2, 0·3–4·8 at preterm).&lt;p&gt;&lt;/p&gt; Interpretation&lt;p&gt;&lt;/p&gt; Low Apgar score at 5 min was strongly associated with the risk of neonatal and infant death. Our findings support its continued usefulness in contemporary practice

    Dendroglaciological Dating of a Little Ice Age Glacial Advance at Moving Glacier, Vancouver Island, British Columbia

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    Dendrochronological investigations at Moving Glacier provide the first calendar-dating of a Little Ice Age glacier advance on Vancouver Island. In 1931, Moving Glacier was within 30 to 50 m of a distinct trimline and terminal moraine marking its maximum Little Ice Age extent. A reconnaissance of the site in 1993 revealed the presence of sheared in situ stumps and detrital trunks inside the 1931 ice limit. Sampling in 1994 showed the site was covered by a mature subalpine forest prior to the glacial advance which overrode the site after 1718 A.D. Following this period of expansion, which saw Moving Glacier expand to its maximum Little Ice Age position after 1818 A.D., the glacier apparently experienced only minimal retreat prior to first being photographed in 1931.Des recherches en dendrochronologie menĂ©es sur le glacier Moving ont permis de dater l'Ă©volution d'un glacier au Petit Âge glaciaire. En 1931, Le glacier Moving Ă©tait situĂ© entre 30 et 50 m d'un Ă©paulement et d'une moraine frontale correspondant Ă  sa limite d'expansion maximale au Petit Âge glaciaire. L'exploration du site en 1993 a permis de dĂ©couvrir des souches et des dĂ©bris de bois in situ Ă  l'intĂ©rieur de la limite glaciaire de 1931. Un Ă©chantillonnage effectuĂ© en 1994 a montrĂ© que le site Ă©tait recouvert d'une forĂȘt subalpine mĂ»re avant l'avancĂ©e glaciaire qui a bouleversĂ© le site aprĂšs 1718 ap. J.-C. AprĂšs la pĂ©riode d'expansion, qui a permis au glacier d'atteindre sa limite maximale aprĂšs 1818 ap. J.-C, le glacier a connu un recul minimal avant d'ĂȘtre photographiĂ© en 1931.Dendrochnronologische Forschungen am Moving-Gletscher ergeben die erste Kalenderdatierung eines GletschervorstoBes wĂąhrend der kleinen Eiszeit auf der Insel Vancouver. 1931 befand sich der Moving-Gletscher innerhalb der 30 bis 50 m einer klaren Abflachung und der EndmorĂąne, was seiner maximalen Ausdehnung in der kleinen Eiszeit entsprach. 1993 fand man bei der Erkundung des Platzes in situ abgescherte BaumstĂčmpfe und TrĂčmmer von BaumstĂąmmen innerhalb der Eisgrenze von 1931. 1994 zeigte eine Probenentnahme, daf3 der Platz mit einem ausgewachsenen subalpinen WaId bewachsen war, bevor der glaziale VorstoB den Platz nach 1718 u.Z. verwandelte. Nach dieser Ausdehnungs-periode, in welcher der Moving-Gletscher nach 1818 u.Z. seine maximale Position in der kleinen Eiszeit erreichte, hat der Gletscher offenbar nur einen minimalen RĂčckzug vollzogen, bevor er 1931 zum 1. Mal photographiert wurde

    A novel profluorescent dinitroxide for imaging polypropylene degradation

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    Free-radical processes underpin the thermo-oxidative degradation of polyolefins. Thus, to extend the lifetime of these polymers, stabilizers are generally added during processing to scavenge the free radicals formed as the polymer degrades. Nitroxide radical precursors, such as hindered amine stabilizers (HAS),1,2 are common polypropylene additives as the nitroxide moiety is a potent scavenger of polymer alkyl radicals (R„). Oxidation of HAS by radicals formed during polypropylene degradation yields nitroxide radicals (RRï‚ąNO„), which rapidly trap the polymer degradation species to produce alkoxyamines, thus retarding oxidative polymer degradation. This increase in polymer stability is demonstrated by a lengthening of the “induction period” of the polymer (the time prior to a sharp rise in the oxidation of the polymer). Instrumental techniques such as chemiluminescence or infrared spectroscopy are somewhat limited in detecting changes in the polymer during the initial stages of degradation. Therefore, other methods for observing polymer degradation have been sought as the useful life of a polymer does not extend far beyond its “induction period
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