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Approximately half of the variation in wellbeing measures overlaps with variation in personality traits. Studies of non-human primate pedigrees and human twins suggest that this is due to common genetic influences. We tested whether personality polygenic scores for the NEO Five-Factor Inventory (NEO-FFI) domains and for item response theory (IRT) derived extraversion and neuroticism scores predict variance in wellbeing measures. Polygenic scores were based on published genome-wide association (GWA) results in over 17,000 individuals for the NEO-FFI and in over 63,000 for the IRT extraversion and neuroticism traits. The NEO-FFI polygenic scores were used to predict life satisfaction in 7 cohorts, positive affect in 12 cohorts, and general wellbeing in 1 cohort (maximal N = 46,508). Meta-analysis of these results showed no significant association between NEO-FFI personality polygenic scores and the wellbeing measures. IRT extraversion and neuroticism polygenic scores were used to predict life satisfaction and positive affect in almost 37,000 individuals from UK Biobank. Significant positive associations (effect sizes <0.05%) were observed between the extraversion polygenic score and wellbeing measures, and a negative association was observed between the polygenic neuroticism score and life satisfaction. Furthermore, using GWA data, genetic correlations of -0.49 and -0.55 were estimated between neuroticism with life satisfaction and positive affect, respectively. The moderate genetic correlation between neuroticism and wellbeing is in line with twin research showing that genetic influences on wellbeing are also shared with other independent personality domains.
Double alkoxides of the general formula Mg[Al(OR)4]2 where R is iso-Pr or sec-Bu were prepared by reacting aluminium and magnesium metals together with the alcohol ROH and purified by vacuum distillation. They were characterised by IR, proton and 27Al NMR spectroscopy and MW determination. A magnesium aluminium double alkoxide was also prepared by treating the commercially available aluminium alkoxide ‘Aliso B’ [a mixed aluminium (iso-propoxide)(sec-butoxide)] with magnesium and iso-propanol. Treatment of magnesium aluminium double alkoxides with water and an alkanolamine (preferably triethanolamine) gives a rigid coherent gel. Viscosity measurements and 27Al NMR spectroscopy suggest that the double alkoxide does not break down to its constituents during hydrolysis. The air-dried gel was shown by XRD to convert quantitatively to spinel on firing to 1500°C. The resistance of the double alkoxide moiety to hydrolysis explains the ease of conversion to spinel on firing. The gel has been used to bind alumina and magnesia grain. Gels suitable for binding refractory grain were obtained only when the alkanolamine content corresponded to one alkanolamine group per metal atom. Electron micrographic and XRD studies showed that in fired refractory pieces, the bonding phase was spinel.
Pressure dependent Deep Level Transient Spectroscopy (DLTS) experiments are used to measure the properties of the deep donors (DX-centers) responsible for the persistent photoconductivity effect in Si-doped AlGaAs. The sample dependence of the DLTS spectra shows evidence for a defect complex involved in the DX-center.
Diamond-like carbon films were prepared by high intensity pulsed ion beam ablation of graphite targets. A 350 keV, 35 kA, 400 ns pulse width beam, consisting primarily of carbon ions and protons, was focused onto a graphite target at a fluence of 15-45 J/cm2. Films were deposited onto substrates positioned in an angular array from normal to the target to 90° off normal. Deposition rates up to 30 nm per pulse, corresponding to an instantaneous deposition rate greater than 1 mm/sec, have been observed. Electrical resistivities between 1 and 1000 ohm·cm were measured for these films. XRD scans showed that no crystalline structure developed in the films. SEM revealed that the bulk of the films contain material with feature sizes on the order of 100 nm, but micron size particles were deposited as well. Both Raman and electron energy loss spectroscopy indicated significant amounts of sp3 bonded carbon present in most of the films.
Kohlmeier-Degos' disease (KDD) is more common in white boys and men with age of onset ranging between 3 weeks of age to 67 years old, most commonly occurring in the second and third decades. The etiology and pathogenesis, although still unknown, is speculated to be immunologic dysfunction, coagulation or fibrinolysis abnormalities, or possible viral infections. Any organ system may be involved; the clinical manifestations are a result of multifocal infarctions. Laparoscopic examination, however, shows lesions similar in appearance to the skin lesions that may involve multiple areas of the small intestine. These lesions are secondary to infarction and have also been found in the esophagus, duodenum, stomach, colon, and rectum. Ischemia and infarction are key pathophysiological mechanisms of the lesions seen. Therapies that have been used include antiplatelets, anticoagulants, immunosuppressive agents, plasma exchange, and nicotine patches. Surgery is indicated in cases of intestinal perforation.
Blood pressure is elevated in most patients during acute ischemic stroke, but the prognostic significance of this is unclear as the current data yield conflicting results.
Admission blood pressure from the 1281 patients in the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) was analyzed for prognostic significance as well as the risk of hemorrhagic transformation. We also examined weighted-average blood pressure over seven days, and the impact of a 30% change in blood pressure in 24 hours. Patients with severe hypertension were excluded from the TOAST trial.
Increasing systolic blood pressure (SBP) on admission, but not diastolic (DBP) or mean arterial pressure (MAP) was predictive of poor outcome, but this effect was not significant after adjustment for other know prognostic factors. Increasing weighted-average SBP and MAP over seven days were predictive for poor outcome, but a 30% change in blood pressure over 24 hours was not.
Admission blood pressure is not an independent prognostic factor in acute ischemic stroke, but the weighted-average of SBP and MAP over seven days probably does have predictive value with higher values having a worse prognosis. A prospective trial of blood pressure control during acute stroke is needed.
Twin studies of lipids have almost exclusively involved Caucasians. People of African descent are known to show a healthier lipid profile, but relatively little is known about ethnic differences in genetic and environmental influences on lipids. One hundred and six African American (AA) and 106 European American (EA) twins (30 singletons and 91 complete pairs: 49 monozygotic, 21 dizygotic and 21 opposite-sex) from the south-eastern United States were studied (mean age 17.9 ± 3.2 years; 79% fasting). Lipids were assayed with the Cholestech LDX system. Analyses were adjusted for fasting status. Generalized estimating equations were used to test for the effects of sex and ethnicity on means, controlling for the dependence within twin pairs. Structural equation modeling was used to estimate genetic and environmental effects on each lipid variable. Females showed higher high-density lipoprotein (HDL) values than males (p < .001) and AAs showed higher HDL values than EAs (p < .001). EA males had higher triglyceride values than other groups (p = .02). All parameter estimates could be set equal across sex. Parameter estimates for total cholesterol, triglycerides and HDL could be set equal across ethnicity. The best fitting model for low- density lipoprotein (LDL) showed higher heritability in AAs (.92) than EAs (.69). Heritabilities ranged from 69% to 92%, with remaining variation explained by nonshared environmental effects. Adjustment for body mass index had virtually no effect on the heritability estimates. In this first twin study on lipids to include AAs, no ethnic differences in heritability were found except for LDL, where AAs exhibited higher estimates.
This study examined cross-validation and test-retest reliability of questions and questionnaire indices commonly used for twin zygosity classification. Mothers of 58 monozygotic (MZ) and 52 dizygotic (DZ) same sex twin pairs were interviewed by telephone to answer questions regarding the similarity of their twins (mean age = 14.6 ± 2.8 years). A logistic regression equation correctly classified 91% of both MZ and DZ twin pairs in our sample using 7 of the 12 zygosity questions. The internal consistency for the total questionnaire (Cronbach's alpha) was 0.88. The median two month temporal stability estimate for the individual questions was r = .56 and r = .79 for the test total. For the cross-validation, zygosity classification indices taken from 9 previous studies were applied to our sample and compared to classification according to DNA microsatellite analyses (agreement range = 44 to 100%). The accuracy of the classification indices was significantly lower than the original studies for 62% of the comparisons. If zygosity determination with DNA markers or blood group typing for all subjects is not feasible, rather than using classification indices based on other studies, an optimal classification scheme can be achieved by using a zygosity questionnaire of which the reliability and validity of the questions is established in a random subsample of the same twin cohort.
Subthreshold conditions (i. e. not meeting full diagnostic criteria for mental disorders in DSM–IV or ICD–10) are prevalent and associated with significant costs and disability. Observed more in primary care and community populations than in speciality settings, varying conceptualisations have been applied to define these conditions.
To examine definitional issues for subthreshold forms of depression (e. g. minor depression) and to suggest future directions for research and nosology in psychiatry and primary care.
A Medline search was conducted. The relevant articles were reviewed with regard to specific categories of information.
Studies applied a myriad of names and definitions for subthreshold depression with varying duration, symptom thresholds and exclusions. Prevalence rates also vary depending upon the definitions, settings and populations researched.
Future research needs to apply methodological and intellectual rigour and systematically consider a broader clinical and nosological context. In addition, collaboration between psychiatry and primary care on research and clinical issues is needed.
Over the past decade, researchers in Japan, Russia, and the United States have been investigating the application of intense-pulsed-ion-beam (IPIB) technology (which has roots in inertial confinement fusion programs) to the surface treatment and coating of materials. The short range (0.1–10 μm) and high-energy density (1–50 J/cm2) of these short-pulsed (t ≥ 1 μs) beams (with ion currents I = 5–50 kA, and energies E = 100–1,000 keV) make them ideal flash-heat sources to rapidly vaporize or melt the near-surface layer of targets similar to the more familiar pulsed laser deposition (PLD) or laser surface treatment. The vaporized material can form coatings on substrates, and surface melting followed by rapid cooling (109 K/s) can form amorphous layers, dissolve precipitates, and form nonequilibrium microstructures.
An advantage of this approach over laser processing is that these beams deliver 0.1–10 KJ per pulse to targets at expected overall electrical efficiencies (i.e., the ratio of extracted ion-beam energy to the total energy consumed in generating the beam) of 15–40% (compared to < 1% for the excimer lasers often used for similar applications). Consequently IPIB hardware can be compact and require relatively low capital investment. This opens the promise of environmentally conscious, low-cost, high-throughput manufacturing. Further, efficient beam transport to the target and excellent coupling of incident ion energy to targets are achieved, as opposed to lasers that may have limited coupling to reflective materials or produce reflecting plasmas at high incident fluence. The ion range is adjustable through selection of the ion species and kinetic energy, and the beam energy density can be tailored through control of the beam footprint at the target to melt (1–10 J/cm2) or to vaporize (10–50 J/cm2) the target surface. Beam pulse durations are short (≥ 1 μs) to minimize thermal conduction. Some disadvantages of IPIB processing over laser processing include the need to form and propagate the beams in vacuum, and the need for shielding of x-rays produced by relatively low-level electron current present in IPIB accelerators. Also these beams cannot be as tightly focused onto targets as lasers, making them unsuitable for applications requiring treatment on small spatial scales.
The response of dairy cows to once a day (OAD) milking was investigated in four trials. Two trials involved Friesians (F) and Jersey cows selected for high (HP) or low (LP) milk protein concentration. Trial 1 compared 74 HP, LP and F cows milked either OAD or twice daily (TAD) for 2 weeks in both mid and late lactation. Trial 2 compared 98 HP, LP and F cows milked OAD or TAD for 12 weeks in early lactation. Trial 3 investigated the repeatability of production loss by milking identical twin cows either OAD or TAD during three 1 week periods. Trial 4 compared the time course of milk production in 32 cows milked every 12 or 24 h for 72 h. Cows milked OAD produced 10–28% less milk and milk solids in early to mid lactation and 9–13% less in late lactation than cows milked TAD. Losses in fat and protein yield were slightly lower than those of milk. HP, LP and F cows did not differ in percentage loss in milk and milk solids in Trial 1, except for loss in protein yield which was lower for HP than LP and F cows. In Trial 2 the losses in milk and milk solids were lower for HP cows than for F cows but the other differences were not significant. Milk storage ability of the udder (hours worth of secretion) was higher and productivity of the udder was lower for HP cows than F cows. Levels of residual milk did not differ among groups. The loss in udder capacity during lactation was greater for cows milked OAD than for those milked TAD. The correlations for repeated estimates of percentage losses in yields of milk and milk solids between successive OAD periods ranged from 0·29 to 0·49. Secretion rate of cows milked OAD was lower during the second 12 h than the first 12 h during each 24 h milking interval. Prediction of OAD performance based on milk composition and udder characteristics was poor. A high level of residual milk was the factor most consistently associated with high loss on OAD milking.
Unilateral vestibular nerve section (VNS) creates a state of acute dysequlibrium which resolves by a process of central compensation. This disturbance resolves quickly and central compensation is complete generally within a month with resolution of symptoms and signs. The course of central compensation following VNS will be similar to that seen after labyrinthectomy because the detachment of hemi-labyrinthine input that is achieved by both will be identical. Six patients are presented who have undergone VNS at least 2.7 years ago (Average 3.5 years); all of them have persisting spontaneous peripheral type horizontal jerk nystagmus, present with optic fixation in five. This is obvious clinically and was confirmed in each case by agreement of three independent observers and has been recorded by electronystagmography (ENG). They are free from marked vestibular symptoms. The explanations of mechanisms involved in central compensation are discussed with respect to this previously unrecorded clinical observation.
Conifer wood, probably spruce (Picea sp.), of middle Wisconsinan age (29,200 ± 500 yr B.P.) was recovered from late-glacial lake sediments from Upper South Branch Pond, Maine. If the wood was derived from a local source, deglaciation of part of northern New England is suggested for this time. The occurrence also has implications for understanding the problem associated with radiocarbon dating of bulk lake sediment containing small amounts of organic matter.