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Little is known about long-term employment outcomes for patients with first-episode schizophrenia-spectrum (FES) disorders who received early intervention services.
We compared the 10-year employment trajectory of patients with FES who received early intervention services with those who received standard care. Factors differentiating the employment trajectories were explored.
Patients with FES (N = 145) who received early intervention services in Hong Kong between 1 July 2001 and 30 June 2002 were matched with those who entered standard care 1 year previously. We used hierarchical clustering analysis to explore the 10-year employment clusters for both groups. We used the mixed model test to compare cluster memberships and piecewise regression analysis to compare the employment trajectories of the two groups.
There were significantly more patients who received the early intervention service in the good employment cluster (early intervention: N = 98 [67.6%]; standard care: N = 76 [52.4%]; P = 0.009). In the poor employment cluster, there was a significant difference in the longitudinal pattern between early intervention and standard care for years 1–5 (P < 0.0001). The number of relapses during the first 3 years, months of full-time employment during the first year and years of education were significant in differentiating the clusters of the early intervention group.
Results suggest there was an overall long-term benefit of early intervention services on employment. However, the benefit was not sustained for all patients. Personalisation of the duration of the early intervention service with a focus on relapse prevention and early vocational reintegration should be considered for service enhancement.
Declaration of interests
No relevant conflicts of interests reported by C.L.M.H., Y.N.S., P.S., H.H.P. and K.K.Y. S.K.W.C., W.C.C. and E.H.M.L. report that they are members of the working group of the Early Assessment Service for Young People with Psychosis (EASY) programme of the Hospital Authority in Hong Kong. E.Y.H.C. is the convener of the working group of the EASY programme of the Hospital Authority in Hong Kong.
The white-backed planthopper, Sogatella furcifera (Horváth) (Hemiptera, Delphacidae), has emerged as a serious rice pest in Asia. In the present study, 12 microsatellite markers were employed to investigate the genetic structure, diversity and migration route of 43 populations sampled from seven Asian countries (Bangladesh, China, Korea, Laos, Nepal, Thailand, and Vietnam). According to the isolation by distance analysis, a significant positive correlation was observed between genetic and geographic distances by the Mantel test (r2 = 0.4585, P = 0.01), indicating the role of geographic isolation in the genetic structure of S. furcifera. A population assignment test using the first-generation migrants detection method (thresholds a = 0.01) revealed southern China and northern Vietnam as the main sources of S. furcifera in Korea. Nepal and Bangladesh might be additional potential sources via interconnection with Vietnam populations. This paper provides useful data for the migration route and origin of S. furcifera in Korea and will contribute to planthopper resistance management.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
This research reports the increased electron energy gain from laser wakefield acceleration in density-modulated plasma with an external magnetic field. Periodic plasma density- modulation can excite higher harmonics of different phase velocities of fundamental wakefield that can assist in improving the self-trapping of pre-accelerated electrons to accelerate them for higher energy. Furthermore, the applied magnetic field assisted self-injection can also contribute in electron energy enhancement during the acceleration. The physical mechanism is described with a theoretical formulation for this scheme. Results of two-dimensional particle-in-cell simulations are reported to understand the proposed idea.
The Slewing Mirror Telescope (SMT) is the UV/optical telescope of UFFO-pathfinder. The
SMT optical system is a Ritchey-Chrétien (RC) telescope of 100 mm diameter pointed by
means of a gimbal-mounted flat mirror in front of the telescope. The RC telescope has a
17 × 17arcmin2 in Field of View and 4.3 arcsec resolution (full width half
maximum of the point spread function) The beam-steering mirror enables the SMT to access a
35 × 35degree region and point and settle within 1 sec. All mirrors were fabricated to
about 0.02 wavelengths RMS in wave front error (WFE) and 84.7% average reflectivity over
200 nm ~ 650 nm. The RC telescope was aligned to 0.05 wavelengths RMS in WFE (test
wavelength 632.8 nm). In this paper, the technical details of the RC telescope and slewing
mirror system assembly, integration, and testing are given shortly, and performance tests
of the full SMT optical system are reported.
Adolescent marijuana use is associated with increased risk for schizophrenia. We previously reported that marijuana misuse in conjunction with specific cannabinoid receptor 1 (CNR1) genetic variants (rs12720071-G-allele carriers) contributed to white-matter (WM) brain volume deficits in schizophrenia patients. In this study, we assessed the influence of another cannabinoid-related gene, mitogen-activated protein kinase 14 (MAPK14), and potential MAPK14–CNR1 gene–gene interactions in conferring brain volume abnormalities among schizophrenia patients with marijuana abuse/dependence. MAPK14 encodes a member of the MAPK family involved in diverse cellular processes, including CNR1-induced apoptosis.
We genotyped 235 schizophrenia patients on nine MAPK14 tag single nucleotide polymorphisms (tSNPs). Approximately one quarter of the sample had marijuana abuse or dependence. Differential effects of MAPK14 tSNPs on brain volumes across patients with versus without marijuana abuse/dependence were examined using ANCOVA.
Of the MAPK14 tSNPs, only rs12199654 had significant genotype effects and genotype × marijuana misuse interaction effects on WM volumes. rs12199654-A homozygotes with marijuana abuse/dependence had significantly smaller total cerebral and lobar WM volumes. The effects of MAPK14 rs12199654 on WM volume deficits remained significant even after controlling for the CNR1 rs12720071 genotype. There were significant main effects of the MAPK14 CNR1 diplotype and diplotype × marijuana interaction on WM brain volumes, with both genetic variants having additive contributions to WM volume deficits only in patients with marijuana misuse.
Given that CNR1-induced apoptosis is preceded by increased MAPK phosphorylation, our study suggests that potential MAPK14–CNR1 gene–gene interactions may mediate brain morphometric features in schizophrenia patients with heavy marijuana use.
The Ultra-Fast Flash Observatory (UFFO) is a space mission to detect the early moments of an explosion from Gamma-ray bursts (GRBs), thus enhancing our understanding of the GRB mechanism. It consists of the UFFO Burst & Trigger telescope (UBAT) for the recognition of GRB positions using hard X-ray from GRBs. It also contains the Slewing Mirror Telescope (SMT) for the fast detection of UV-optical photons from GRBs. It is designed to begin the UV-optical observations in less than a few seconds after the trigger. The UBAT is based on a coded-mask X-ray camera with a wide field of view (FOV) and is composed of the coded mask, a hopper and a detector module. The SMT has a fast rotatable mirror which allows a fast UV-optical detection after the trigger. The telescope is a modified Ritchey-Chrétien telescope with the aperture size of 10 cm diameter, and an image intensifier readout by CCD. The UFFO pathfinder is scheduled to launch into orbit on 2012 June by the Lomonosov spacecraft. It is a scaled-down version of UFFO in order to make the first systematic study of early UV/optical light curves, including the rise phase of GRBs. We expect UBAT to trigger ~44 GRBs/yr and expect SMT to detect ~10 GRBs/yr.
Alloys based on near-equiatomic NiTi are capable of thermoelastic martensite transformations which give rise to shape memory and superelasticity (pseudoplasticity) effects. In particular, at temperatures above Ms and Af but below Md, NiTi alloys can deform by mechanisms of stressinduced martensite transformation and may display large anelastic strains which involve little or no deformation by slip. Under these conditions, the strain-controlled fatigue resistance of NiTi alloys may be exceptionally high . In contrast, fcc metals like copper will, during strain controlled fatigue, eventuate severe plastic strain localization in the form of persistent slip bands (PSBs), whose behavior at free surfaces is intimately associated with fatigue crack initiation . It is well known that fatigue crack initiation in fcc metals can be delayed by modifying surfacebreaking PSB structure or environment [3,4]. However, any attempt to strengthen the surface region in order to impede surface expression of persistent slip bands must contend with the large subsurface strain localizations enforced by the PSBs, which subject the film to strain cycling at roughly the characteristic PSB shear strain amplitude. Thermoelastic nickel-titanium alloys, capable of pseudoplastic straining, may be uniquely suited to the role of surface protection in situations where fatigue crack initiation is associated with PSB interaction with the external environment. In the present work, thin surface microalloys of NiTi, produced by ion sputtering, have been applied to polycrystalline copper fatigue specimens that were subsequently subjected to both monotonic loading, and fatigue under plastic strain control to produce mature PSB structures in the bulk material. Optical and scanning electron microscopy studies are described which assess the effect of the NiTi surface microalloy on the behavior of PSBs in the near surface region, and the attendant effect of the films on surface behavior of persistent slip bands. Although the results are incomplete with respect to the effects of the film on fatigue crack initiation, it has been shown for the first time that martensite transformation can be stress-induced (at temperatures above Ms) in a thin NiTi film on a plastically deforming substrate. This finding augurs well for the potential of such films to effectively suppress slip band penetration during low cycle fatigue.
Titanium silicides were prepared by coevaporation of Ti and Si on Si substrates at intermediate substrate temperatures followed by high temperature annealing. Depending on the deposition conditions, transmission electron diffraction analyses revealed two different halo patterns from the as-deposited samples. Variations in the deposition conditions included substrate temperature, deposition rate, and film thickness. Radial distribution functions were calculated to estimate the short range ordering of the amorphous phases. The interatomic distances of all the titanium silicide compounds were also calculated in order to compare them with the atomic ordering of amorphous phases. Phase transition from these amorphous phases to the first crystalline silicide is discussed in terms of kinetic variations as well as the atomic ordering.
Discrete and coalesced monocrystalline layers of lateral- and pendeo-epitaxially grown GaN and AlxGal−xN layers originating from GaN stripes deposited within windows contained in SiO2 masks or from side walls of GaN seed structures containing SiNx top masks have been grown via organometallic vapor phase deposition on GaN/AlN/6H-SiC(0001) substrates. Multilayer heterostructures of GaN and AlxGal−N were also achieved. Scanning and transmission electron microscopies and atomic force microscopy were used to evaluate the microstructures, the type and distribution of dislocations and the surface roughness of the resulting films. The extent and microstructural characteristics of the laterally overgrown GaN regions were a strong function of stripe orientation and temperature. These regions contained a low density of dislocations. The RMS roughness of the (1120) sidewall plane of the pendeoepitaxial structures was approximately 0.100 nm.
Metal-insulator-semiconductor (MIS) capacitors have been fabricated on n-type GaN (0001) films using thermally grown Ga2O3, remote plasma enhanced chemical vapor deposited (RPECVD) SiO2, and molecular beam epitaxy (MBE) AIN as the gate insulator and Al as the gate electrode. Each GaN epitaxial layer was grown by organometallic chemical vapor deposition (OMCVD) on a 6H-SiC(0001) substrate on which was previously deposited a 1000Å buffer layer of AIN. Nitrogen-free polycrystalline films of Ga2O3 were grown on the GaN. Capacitancevoltage measurements of capacitors fabricated from this oxide showed distinct depletion and accumulation regions with significant leakage. The AIN and SiO2 capacitors demonstrated better electrical characteristics than the Ga2O3 because of lower leakage. The RPECVD SiO2/GaN heterostructures, in particular, showed good agreement with the curves calculated for an ideal oxide and a small amount of hysteresis.
Rapid thermal annealing (RTA) was applied to anneal polycrystalline CdTe thin films evaporated on CdS/ITO substrate and the effects of rapid thermal annealing temperatures and gas environments were studied. X-ray diffractometer (XRD), X-ray photoelectron spectroscopy(XPS), energy dispersive X-ray spectroscopy(EDX), cross-sectional transmission microscopy(TEM), and micro-EDX in TEM were used to characterize physical and chemical properties of rapid thermal annealed CdTe thin films. Complete CdTe/CdS photovoltaic cells were fabricated and I-V characteristics of these cells were measured under the illumination. Results showed that the bulk composition of CdTe remained stoichiometric to 550°C in the air environment and surface composition became Cd-rich. Cross-sectional TEM and micro-EDX showed columnar grains and micro-twins remained even after RTA, however, sulfur content in rapid thermal annealed CdTe caused by sulfur diffusion from CdS during the annealing was much smaller than that by furnace annealing. Among the investigated RTA temperatures and gas environments, the cell made with CdTe annealed at 550°C in the air showed the best solar energy conversion efficiency.
We have deposited thin films of diamond-like-carbon by plasma enhanced chemical vapor deposition, and examined the electron emission characteristics of the optimized DLC-coated field emitters. The bonding spectra and microstractures are controlled by energetic ions depending on deposition parameters which affect the structural, optical, and electrical characteristics. Raman spectra and IR analysis identify that as-deposited DLC contains mixtures of sp2- and sp3-bonding with a wide range of hydrogen, but annealing causes its conversion to graphite structure due to a depletion of hydrogen. From the measurement of field emission characteristics, turn-on gate voltage is lowered to 50 V and anode current is increased for DLC-coated Si field emitter tip arrays.
An asymmetric dual gate poly-Si thin film transistors (TFTs), which is consist a long-gate TFT and a short-gate TFT, were fabricated in order to suppress the kink current and increase the reliability. The long-gate TFT operates in a linear regime and limits the total current flow by its current operation region. The asymmetric dual-gate does not exhibit from the kink current in a high drain bias due to the distribution of lateral electric field. The asymmetric dual-gate structure improves kink-free characteristics compared with conventional single and dual-gate TFTs. The hot-carrier stress reliability is successfully improved due to kink current suppression.
This study was performed to test the hypothesis that there are ‘hotspots’, i.e. geographical heterogeneity, of dengue transmission. Data from two repeat serosurveys in two villages in Vietnam were used to identify incident infections and to relate these to prevalence at baseline and thus assess geographical heterogeneity, i.e. clustering, in dengue transmission. A total of 400 households were surveyed; serological data from 521 children at baseline and from 119 children at follow-up were included in a spatial analysis. Geographical heterogeneity of dengue transmission was explored using a permutation null distribution test. This showed for the first time evidence of clustering of dengue virus transmission at the household level in asymptomatic children. Risk areas could be identified by seroprevalence surveys combined with mapping. Control of dengue virus transmission could be supported by identification and control of hotspots.
The structure and composition of Cr-nitrides formed on an electroplated hard Cr layer during an ion-nitriding process were analyzed, and its growth kinetics was examined as a function of the ion-nitriding temperature and time to establish a computer simulation model for the prediction of growth behavior of the Cr-nitride layer. The Cr-nitrides formed during the ion-nitriding at 550–770 °C were composed of outer CrN and inner Cr2N layers. A nitrogen diffusion model in the multilayer, based on fixed-grid finite difference method, was applied to simulate the growth kinetics of Cr-nitride layers. By measuring the thickness of Cr-nitride layers as a function of ion-nitriding temperature and time, the activation energy (Q) and nitrogen diffusion constant (Do) were determined for growth of CrN and Cr2N; the result was applied to simulate the growth kinetics of Cr-nitride layers, and reasonable good agreement was obtained with the experimental results.
Polycrystalline samples of HgBa2(Ca0.86Sr0.14)2Cu3O8+δ (denoted as Hg-1223) were prepared by a precursor route, which involves the reaction between HgO and two precursors: Ba2CuO3+x and Ca0.14CuO2. X-ray powder diffraction analysis revealed that the Hg-1223 is isostructural with pristine HgBa2Ca2Cu3O8−δ and TlBa2Ca2Cu3O9−δ. The Hg-1223 has tetragonal symmetry with space group P4/mmm, and lattice parameters a = 3.8648(2) Å and c = 16.0319(2) Å. The as-synthesized Hg-1223 sample has a Tc of about 126 K. After annealing in an oxygen atmosphere at 280 °C for 10 h, the Tc increased to 132 K. Using this precursor pathway, Hg-1223 samples can be reproducibly synthesized.
Thin films of LiNbO3 were fabricated on sapphire(012), MgO(OOl), and Si(111) substrates by the sol-gel process. Under optimized conditions, films deposited onto sapphire(012) were epitaxially grown. Preferred orientations, however, were not observed in the films on MgO(001) and Si(111) by x-ray diffraction measurements. Morphology of the epitaxial films on sapphire(012) was examined by scanning electron microscopy, which indicated that the films were smooth and had a pore-free surface. Electrical and optical measurements on the epitaxial films revealed that the properties of the films were very similar to those of the single crystalline LiNbO3, while films deposited onto Si(111) did not show any orientational behaviors. The highest quality films with epitaxy were obtained only on sapphire(012). The remaining substrates appeared to be not suitable for growing epitaxial LiNbO3 films by the sol-gel method.
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