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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 subject of the production within Diatoms of spores, en docysts, &c., has been worked at by several observers, principally Castracane in recent years, and before him O'Meara and Rabenhorst. Some of these observers have noted ciliated, spore-like bodies, probably parasitic or casual intrusive organisms; others, notably Castracane, have recorded oval and other cysts winch have not been figured and the characters of which are difficult to realise. Miquel has made an experimental examination of the subject without being able to confirm Castracane's results. Castracane has also recorded the presence, as he thinks, of “gonids or embryonal forms” within a fossil Diatom (Coscinodiscus punctatus) in a marine deposit of miocene age. During March of this year I tow-netted near the Bell Rock a large quantity of Coscinodiscus concinnus — with many dead valves separated at the girdle. These frequently contained not only other and smaller individuals of the same species, but other species of diatoms and casual objects as well, and the observation makes one cautious about accepting evidence of the character brought forward by Castracane as to his fossil form.
Lauder, in describing forms of Bacteriastrum and Chœtoceros, observed the formation of endocysts. “At certain times, or under certain circumstances, the endochrome does not divide after the lengthening of the frustule, but secretes a siliceous envelope and becomes a gonidium or sporangium, consisting of a cell with two rounded ends, and a connecting hoop, one end being smaller than the other ….
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.
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.
The possibility of using air-coupled ultrasound to find delaminations between layers in paintings was investigated. Simulations of modern paintings were constructed with hardboard as the support layer, and a layer of gesso, an animal hide glue and chalk, as the upper layer. Delaminations were introduced between the two layers. Scanning the samples using air-coupled ultrasound clearly showed these flaws. A transmitting transducer, which was 25 mm in diameter and had a focal length of 51 mm, was placed 11 mm from the back surface of the sample and an identical receiving transducer was placed 51 mm from the front surface. The transducers were operated in a tone burst mode at a center frequency of 475 kHz. Signal enhancement techniques were used to improve the contrast of the data.
We have successfully grown undoped GaAs of very high resistivity on Si by MOCVD. The back and side edges of the Si substrate were coated with a Si3N4/SiO2 stacked layer to suppress Si incorporation Into GaAs by the gas phase transport mechanism during MOCVD growth. A 3- μm-thick GaAs layer was grown on this Si substrate at 750 °C in an atmospheric MOCVD reactor using the two-step growth technique. The electron concentration measured by a Polaron C-V profiler is 3xl0l4 cm−3, as low as that of GaAs grown on GaAs substrate, up to the depth of 1.5 μm from the surface.
Ionomers have been defined as copolymers that have a certain proportion of ionic groups. The ionic groups have a significant effect on the mechanical properties of the copolymers. This is generally due to aggregation of ions in a low dielectric medium. The primary result is to restrict chain motion and raise the glass transition temperature. These attributes have relevance to molecular imprinting, since restricted chain motion should help preserve the integrity of the binding site. The connection between ionomers and molecular imprinting has come from the production of metal ion imprinted resins. Metal ions are used in the production of molecularly imprinted polymer ion exchange resins and ionically permeable membranes. The polymers have applications as separations media, sequestering media and as ion selective sensors. Metal ions are also being used to form imprinted polymers based on metal mediated imprint binding. We have prepared ion exchange resins, selectively permeable polymer membranes, ion selective electrodes and ion selective optical sensors using a modified version of the molecular imprinting technique. The modification is a reduction in the amount of covalent crosslinking used to form the polymers. This reduction may be justified by the presence of residual metal ion crosslinking in the immediate region of the imprinted binding site. The effects of metal ions on the thermal and mechanical properties of the polymers, as well their impact on binding selectivity are critical variables.
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. 
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.
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.