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Psychoses, especially schizophrenia, are often preceded by cognitive deficits and psychosis risk states. Altered metabolic profiles have been found in schizophrenia. However, the associations between metabolic profiles and poorer cognitive performance and psychosis risk in the population remain to be determined.
Detailed molecular profiles were measured for up to 8976 individuals from two general population-based prospective birth cohorts: the Northern Finland Birth Cohort 1986 (NFBC 1986) and the Avon Longitudinal Study of Parents and Children (ALSPAC). A high-throughput nuclear magnetic resonance spectroscopy platform was used to quantify 70 metabolic measures at age 15–16 years in the NFBC 1986 and at ages 15 and 17 years in ALSPAC. Psychosis risk was assessed using the PROD-screen questionnaire at age 15–16 years in the NFBC 1986 or the psychotic-like symptoms assessment at age 17 years in ALSPAC. Cognitive measures included academic performance at age 16 years in both cohorts and general intelligence and executive function in ALSPAC. Logistic regression measured cross-sectional and longitudinal associations between metabolic measures and psychosis risk and cognitive performance, controlling for important covariates.
Seven metabolic measures, primarily fatty acid (FA) measures, showed cross-sectional associations with general cognitive performance, four across both cohorts (low density lipoprotein diameter, monounsaturated FA ratio, omega-3 ratio and docosahexaenoic acid ratio), even after controlling for important mental and physical health covariates. Psychosis risk showed minimal metabolic associations.
FA ratios may be important in marking risk for cognitive deficits in adolescence. Further research is needed to clarify whether these biomarkers could be causal and thereby possible targets for intervention.
The Omani basement is located spatially distant from the dominantly juvenile Arabian–Nubian Shield (ANS) to its west, and its relationship to the amalgamation of those arc terranes has yet to be properly constrained. The Jebel Ja'alan (NE Oman) basement inlier provides an excellent opportunity to better understand the Neoproterozoic tectonic geography of Oman and its relationship to the ANS. To understand the origin of this basement inlier, we present new radiogenic isotopic data from igneous bodies in Jebel Ja'alan. U–Pb and 40Ar/39Ar geochronological data are used to constrain the timing of magmatism and metamorphism in the jebel. Positive εHf and εNd values indicate a juvenile origin for the igneous lithologies. Phase equilibria modelling is used to constrain the metamorphic conditions recorded by basement. Pressure–temperature (P–T) pseudosections show that basement schists followed a clockwise P–T path, reaching peak metamorphic conditions of c. 650–700°C at 4–7.5 kbar, corresponding to a thermal gradient of c. 90–160°C/kbar. From the calculated thermal gradient, in conjunction with collected trace-element data, we interpret that the Jebel Ja'alan basement formed in an arc environment. Geochronological data indicate that this juvenile arc formed during Tonian time and is older than basement further west in Oman. We argue that the difference in timing is related to westwards arc accretion and migration, which implies that the Omani basement represents its own tectonic domain separate to the ANS and may be the leading edge of the Neoproterozoic accretionary margin of India.
The movement of fluids through a porous medium is a function of the material type and the size and morphology of the voids. In the conservation of painted artworks, the movement of materials (for example, cleaning solutions) is a major factor in how a work reacts to treatments and a large influence on how the work will change with time. Of particular importance in the conservation of painted surfaces is the preparatory layer. This is a highly active transport medium because it is generally highly porous and a comparatively large and uniform component of a painted surface. In this work, a gesso film of calcium carbonate and rabbit skin glue, typical of the preparatory layer of many painted works, and an acrylic-based gesso film were imaged by focused ion beam (FIB) scanning. The gessoes were milled and scanned with gallium ions serially, in sequential planes orthogonal to the plane of the film. This yielded quantifiable measurements of the fine internal structures at a resolution far higher than previously reported for this type of material. This enabled a greater understanding of the geometry of the internal surfaces, increasing the understanding of the mechanics of capillary flow and diffusive behavior in this extremely common and significant material.
Vast numbers of bronze coins have been, and continue to be, excavated from archaeological sites around the Greco-Roman world. While often of little value from a strictly numismatic point of view, these coins provide invaluable data within their respective stratigraphic contexts and are used to date occupational and architectural phases more precisely than by ceramics alone. Unfortunately, the build-up of corrosion and mineralization on these coins during their centuries of burial often obscures their legends. Rather than employing potentially destructive and time-consuming chemical or mechanical cleaning techniques to reveal these features, commercially available Micro-focus X-Ray CT systems are now sufficiently well developed to reveal original surface features and to permit identification by a trained numismatist without any cleaning at all.
Metasedimentary rocks constitute an important but comparatively poorly understood part of the Antarctic Peninsula. Herein we report single-grain U-Pb detrital-zircon ages from samples of the Trinity Peninsula and Botany Bay Groups of north-western Graham Land. All studied samples are dominated by a large and narrowly defined population of late Palaeozoic zircons. Significant early–middle Palaeozoic and minor Neoproterozoic and Mesoproterozoic sub-populations constitute the majority of pre-Carboniferous grains. These detrital-zircon age populations are consistent with sediment derivation entirely from western Gondwana sources. Despite the clear Gondwana signatures, our data suggest that the Trinity Peninsula Group province was either a parautochthonous peri-Gondwanan terrane later accreted to the Antarctic Peninsula, or a significant topographic barrier precluded voluminous sediment contributions from the interior of Gondwana. Statistical comparisons with similar metasedimentary complexes of southern South America, the South Shetland Islands and eastern New Zealand indicate a diversity of sediment provenance not previously recognized, but may provide a means to better determine the pre-break-up configuration of western Gondwana. Although insufficient to definitively restore Antarctic Peninsula components adjacent to South American complexes, some Trinity Peninsula Group samples exhibit robust affinities to the Miers Bluff Formation in the South Shetland Islands and the Duque de York and Main Range Metamorphic Complexes of the Patagonian Andes.
To assess the folate and vitamin B12 status of a group of Vietnamese women of reproductive age and to estimate the rate of neural tube defects (NTD) based on red blood cell (RBC) folate concentrations.
Design and subjects
A representative sample of non-pregnant women (15–49 years) living in Hanoi City (n 244) and Hai Duong Province (n 245).
RBC folate, plasma vitamin B12 and plasma holo-transcobalamin (holoTC), a sensitive indicator of vitamin B12 status.
Mean (95 % CI) concentrations of RBC folate, plasma B12 and plasma holoTC were 856 (837, 876) nmol/l, 494 (475, 513) pmol/l and 78 (74, 82) pmol/l, respectively. Only 3 % and 4 % of women had plasma B12 and holoTC concentrations indicative of deficiency. No woman had an RBC folate concentration indicative of deficiency (<317 nmol/l). Only 47 % of women had an RBC folate concentration ≥905 nmol/l. Accordingly, we predict the NTD rate in these regions of Vietnam to be 14·7 (14·2, 15·1) per 10 000 pregnancies.
There was no evidence of folate and vitamin B12 deficiency among this population of Vietnamese women. However, suboptimal folate status may be placing three out of five women at increased risk of NTD. Reductions in NTD rates are still possible and women would benefit from additional folic acid during the periconceptional period from either supplements or fortified foods.
Micro-scale Focused Ion Beam (FIB) machined cantilevers were manufactured in single crystal copper, polycrystalline copper and a copper-bismuth alloy. These were imaged and tested in bending using a nanoindenter. Cantilevers machined inside a single grain of polycrystalline copper were tested to determine their (anisotropic) Young's modulus: results were in good agreement with values calculated from literature values for single crystal elastic constants. The size dependence of yield behavior in the Cu microcantilevers was also investigated. As the thickness of the specimen was reduced from 23μm to 1.7μm the yield stress increased from 300MPa to 900MPa. Microcantilevers in Cu-0.02%Bi were manufactured containing a single grain boundary of known character, with a FIB-machined sharp notch on the grain boundary. The cantilevers were loaded to fracture allowing the fracture toughness of grain boundaries of different misorientations to be determined.
Background: Home-fortification is a new strategy of adding micronutrients including zinc and iron to home-made foods. Zinc supplementation may prevent morbidity and mortality related to diarrheal illnesses, and iron supplementation may improve cognitive development, in children.
Objectives: To project clinical and economic effects of home-fortification in children in an urban slum of Karachi, Pakistan.
Methods: This is a cost benefit analysis of 5,000 simulated male and female infants (6–12 months) assigned to micronutrients or placebo for 4 months and followed for 55 years. We linked the effect of zinc on longitudinal prevalence of diarrhea to mortality, and the effect of iron on hemoglobin to IQ scores and lifetime earnings. Cost estimates were based on volumes of resource utilization from the Pakistan Sprinkles Diarrhea study. Main outcome was incremental benefit defined as the gain in lifetime earnings after accounting for the incremental costs of micronutrients over placebo (societal perspective).
Results: Our model projected that the reduction in diarrhea and improvement in hemoglobin concentrations through home-fortification was associated with reduced child mortality, higher IQ scores, and higher earnings. The present value of incremental benefit was $106 (95 percent probability interval = $17 to $193) U.S. dollars, which corresponds to $464.79 ($74.54 to $846.27) international dollars using a purchasing power parity exchange rate.
Conclusions: Home-fortification appears to improve clinical outcomes at a reasonable cost, and may actually be cost beneficial when lifetime earnings are considered.
To identify the rate of treatment failure in emergency department patients with cellulitis.
This prospective observational convenience study enrolled adult patients with uncomplicated cellulitis. Physicians performed a standardized assessment prior to treatment. To calculate the interrater reliability of the assessment, duplicate data collection forms were completed on a small subsample of patients. Treatment failure was defined as the occurrence of any one of the following events after the initial emergency department visit: incision and drainage of abscess; change in antibiotics (not due to allergy/intolerance); specialist consultation; or, hospital admission. Comparison of means and proportions between the 2 groups was performed with univariate associations, using parametric or non-parametric tests where appropriate.
Seventy-five patients were enrolled; 57% were male, the mean age was 48 (standard deviation 19), 71 (95%) patients had extremity cellulitis and 10 (13%) had abscess with cellulitis. Fourteen episodes (18.7%, 95% confidence interval [CI] 11%–28%) were classified as treatment failures, with an oral antibiotic failure rate of 6.8% (95% CI 2%–22%) and an emergency department-based intravenous antibiotic failure rate of 26.1% (95% CI 16%–40%). Patients with treatment failure were older (mean age 59 yr v. 46 yr, p = 0.02) and more likely to have been taking oral antibiotics at enrolment (50% v. 16.4%, p = 0.01). Patients with a larger surface area of infection were also more likely to fail treatment (465.1 cm2 v. 101.5 cm2, p < 0.01). Interrater agreement was high for the presence of fever (kappa 1.0) and the size of surface area of infection (intraclass correlation coefficient 0.98), but low for assessments of both severity (kappa 0.35) and need for admission (kappa 0.46).
The treatment of cellulitis with daily emergency department–based intravenous antibiotics has a failure rate of more than 25% in our centre. Cellulitis patients with a larger surface area of infection and previous (failed) oral therapy are more likely to fail treatment. Further research should focus on defining eligibility for treatment with emergency department-based intravenous antibiotics.
Despite a ≥75% reduction in the geographic range of Mongolian gazelles Procapra gutturosa over the past 50 years, the species is still recognized as the most numerous large grassland herbivore in Asia. Its actual population size, however, is still disputed, and we therefore estimated its numbers in an 80,000 km2 area in the eastern steppe of Mongolia by driving long-distance (1,200–1,400 km) transect surveys during spring and autumn 2000–2002. Quantitative estimates of gazelle numbers are essential for understanding the causes of changes in the population, and thus devising conservation strategies to assure its long-term viability. Observed herds ranged in size from 1–4,000; among surveys, median herd sizes varied from 14–42. Density estimates varied from 10.7 gazelles km−2 in spring to 11.5 gazelles km−2 in autumn, with total population estimates of 803,820 (483,790–1,330,100 95% confidence interval) and 870,625 (499,432–1,491,278 95% confidence interval), respectively. Confidence limits were wide, and to obtain a coefficient of variation of 20%, transect lengths would need to be extended three- to four-fold. Until more efficient means for conducting population surveys can be implemented, driving long-distance transects, combined with distance analysis, seem to provide the best quantitative estimate of Mongolian gazelle populations.
Patients with psychosis have activation of the hypothalamic-pituitary-adrenal (HPA) axis during the acute phase of the psychosis. Whether this has any morphological consequences for the pituitary gland is currently unknown.
To examine pituitary volume variation in people at different stages of psychotic disorder.
Pituitary volume was measured using 1.5 mm, coronal magnetic resonance images in 24 people with first-episode psychosis, 51 with established schizophrenia and 59 healthy controls.
Compared with the control group, the people with first-episode psychosis had pituitary volumes that were 10% larger, whereas those with established schizophrenia had pituitary volumes that were 17% smaller. In both of the groups with psychosis, there was no difference in pituitary volume between those receiving typical antipsychotic drugs and those receiving atypical antipsychotics.
The first episode of a psychosis is associated with a larger pituitary volume, which we suggest is due to activation of the HPA axis. The smaller pituitary volume in the group with established schizophrenia could be the consequence of repeated episodes of HPA axis hyperactivity.
We present a theoretical study of the optical properties of one-dimensional (1-D) metal nanostructures including nanorods and nanotubes. Although the optical properties of gold nanotubes are similar to that of gold nanorods, both the longitudinal and transverse plasmon resonances of gold nanotubes show much larger red-shifting and narrower. The E-field calculations indicate that the 1-D gold nanostructures, particularly gold nanotubes have great potential for applications to SERS.
Molecular imprinting is a useful technique for making a chemically selective binding site.  The method involves building a synthetic polymeric scaffold of molecular compliments containing the target molecule with subsequent removal of the target to leave a cavity with a structural “memory” of the target. Molecularly imprinted polymers can be employed as selective adsorbents of specific molecules or molecular functional groups. Sensors for specific molecules can be made using optical transduction through chromophores residing in the imprinted site. The use of metal ions as chromophores can improve selectivity due to directional bonding. The combination of molecular imprinting and spectroscopic selectivity can result in sensors that are highly sensitive and nearly immune to interferences. 
To determine if peripheral venous blood gas values for pH, partial pressure of carbon dioxide (PCO2) and the resultant calculated bicarbonate (HCO3) predict arterial values accurately enough to replace them in a clinical setting.
This prospective observational study was performed in a university tertiary care emergency department from June to December 1998. Patients requiring arterial blood gas analysis were enrolled and underwent simultaneous venous blood gas sampling. The following data were prospectively recorded: age, sex, presenting complaint, vital signs, oxygen saturation, sample times, number of attempts and indication for testing. Correlation coefficients and mean differences with 95% confidence intervals (CIs) were calculated for pH, PCO2 and HCO3. A survey of 45 academic emergency physicians was performed to determine the minimal clinically important difference for each variable.
The 218 subjects ranged in age from 15 to 90 (mean 60.4) years. The 2 blood samples were drawn within 10 minutes of each other for 205 (96%) of the 214 patients for whom data on timing were available. Pearson’s product–moment correlation coefficients between arterial and venous values were as follows: pH, 0.913; PCO2, 0.921; and HCO3, 0.953. The mean differences (and 95% CIs) between arterial and venous samples were as follows: pH, 0.036 (0.030–0.042); PCO2, 6.0 (5.0–7.0) mm Hg; and HCO3, 1.5 (1.3–1.7) mEq/L. The mean differences (± 2 standard deviations) were greater than the minimum clinically important differences identified in the survey.
Arterial and venous blood gas samples were strongly correlated, and there were only small differences between them. A survey of emergency physicians suggested that the differences are too large to allow for interchangeability of results; however, venous values may be valid if used in conjunction with a correction factor or for trending purposes.