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Schizophrenia is a complex mental disorder with high heritability and polygenic inheritance. Multimodal neuroimaging studies have also indicated that abnormalities of brain structure and function are a plausible neurobiological characterisation of schizophrenia. However, the polygenic effects of schizophrenia on these imaging endophenotypes have not yet been fully elucidated.
To investigate the effects of polygenic risk for schizophrenia on the brain grey matter volume and functional connectivity, which are disrupted in schizophrenia.
Genomic and neuroimaging data from a large sample of Han Chinese patients with schizophrenia (N = 509) and healthy controls (N = 502) were included in this study. We examined grey matter volume and functional connectivity via structural and functional magnetic resonance imaging, respectively. Using the data from a recent meta-analysis of a genome-wide association study that comprised a large number of Chinese people, we calculated a polygenic risk score (PGRS) for each participant.
The imaging genetic analysis revealed that the individual PGRS showed a significantly negative correlation with the hippocampal grey matter volume and hippocampus–medial prefrontal cortex functional connectivity, both of which were lower in the people with schizophrenia than in the controls. We also found that the observed neuroimaging measures showed weak but similar changes in unaffected first-degree relatives of patients with schizophrenia.
These findings suggested that genetically influenced brain grey matter volume and functional connectivity may provide important clues for understanding the pathological mechanisms of schizophrenia and for the early diagnosis of schizophrenia.
Although it is crucial to improve the treatment status of people with severe mental illness (SMI), it is still unknown whether and how socioeconomic development influences their treatment status.
To explore the change in treatment status in people with SMI from 1994 to 2015 in rural China and to examine the factors influencing treatment status in those with SMI.
Two mental health surveys using identical methods and ICD-10 were conducted in 1994 and 2015 (population ≥15 years old, n = 152 776) in the same six townships of Xinjin County, Chengdu, China.
Compared with 1994, individuals with SMI in 2015 had significantly higher rates of poor family economic status, fewer family caregivers, longer duration of illness, later age at first onset and poor mental status. Participants in 2015 had significantly higher rates of never being treated, taking antipsychotic drugs and ever being admitted to hospital, and lower rates of using traditional Chinese medicine or being treated by traditional/spiritual healers. The factors strongly associated with never being treated included worse mental status (symptoms/social functioning), older age, having no family caregivers and poor family economic status.
Socioeconomic development influences the treatment status of people with SMI in contemporary rural China. Relative poverty, having no family caregivers and older age are important factors associated with a worse treatment status. Culture-specific, community-based interventions and targeted poverty-alleviation programmes should be developed to improve the early identification, treatment and recovery of individuals with SMI in rural China.
Population-based colorectal cancer (CRC) screening programs that use a fecal immunochemical test (FIT) are often faced with a noncompliance issue and its subsequent waiting time (WT) for those FIT positives complying with confirmatory diagnosis. We aimed to identify factors associated with both of the correlated problems in the same model.
A total of 294,469 subjects, either with positive FIT test results or having a family history, collected from 2004 to 2013 were enrolled for analysis. We applied a hurdle Poisson regression model to accommodate the hurdle of compliance and also its related WT for undergoing colonoscopy while assessing factors responsible for the mixture of the two outcomes.
The effect on compliance and WT varied with contextual factors, such as geographic areas, type of screening units, and level of urbanization. The hurdle score, representing the risk score in association with noncompliance, and the WT score, reflecting the rate of taking colonoscopy, were used to classify subjects into each of three groups representing the degree of compliance and the level of health awareness.
Our model was not only successfully applied to evaluating factors associated with the compliance and the WT distribution, but also developed into a useful assessment model for stratifying the risk and predicting whether and when screenees comply with the procedure of receiving confirmatory diagnosis given contextual factors and individual characteristics.
Seed reserves play vital roles in seed germination and seedling growth and their variation may be related to various environment factors, plant traits and phylogenetic history. Here, the evolutionary correlation associated with seed mass and altitude and carbon (C), nitrogen (N) and phosphorus (P) allocation of seeds among 253 alpine herbaceous plants was tested. In this study, phylogeny had strong limitations on nutrient allocation of seeds across species, and species from younger phylogenetic groups tended to have higher N and P contents, which might be considered as the evolutionary selection of seed plants. Higher seed N and P content would help seedlings to gain more survival chance and stronger competitive capacity, and their progeny would be more likely to be preserved. When phylogeny was considered, altitude only had a significant positive effect on P content, but the negative effects on seed mass were all expressed. The independent effects of altitude and seed mass suggest that the nutrient allocation of seeds might be affected by both environment and plant traits. In addition, altitude and seed mass displayed partial overlapping effects on nutrient allocation of seeds. The negative effects of seed mass were affected slightly by altitude, whereas altitude only had a significant positive effect on P content when seed mass was controlled. Above all, seed P content showed obvious and general correlations with seed mass, altitude and age of clade, which indicated that higher seed P content might be an adaptive selection of species associated with growth and survival of progeny.
Owing to lack of a definitive correlation between carbon supports and catalytic activity of single-atom Fe-active sites, rational design and preparation of single-atom Fe catalysts have so far been elusive. Herein we designed and prepared one-dimensional core–shell nanostructured single-atom Fe catalysts, in which carbon nanofibers and carbon nanotubes with different crystallinities and electrical conductivities were used as supports to host single-atom Fe-active sites. It was found that the carbon supports with higher electrical conductivity accelerate charge transfer and enhance the oxygen reduction reaction (ORR) activity of single-atom Fe-active sites as well as the ORR durability of the final catalyst.
We report the utility of whole-genome sequencing (WGS) conducted in a clinically relevant time frame (ie, sufficient for guiding management decision), in managing a Streptococcus pyogenes outbreak, and present a comparison of its performance with emm typing.
A 2,000-bed tertiary-care psychiatric hospital.
Active surveillance was conducted to identify new cases of S. pyogenes. WGS guided targeted epidemiological investigations, and infection control measures were implemented. Single-nucleotide polymorphism (SNP)–based genome phylogeny, emm typing, and multilocus sequence typing (MLST) were performed. We compared the ability of WGS and emm typing to correctly identify person-to-person transmission and to guide the management of the outbreak.
The study included 204 patients and 152 staff. We identified 35 patients and 2 staff members with S. pyogenes. WGS revealed polyclonal S. pyogenes infections with 3 genetically distinct phylogenetic clusters (C1–C3). Cluster C1 isolates were all emm type 4, sequence type 915 and had pairwise SNP differences of 0–5, which suggested recent person-to-person transmissions. Epidemiological investigation revealed that cluster C1 was mediated by dermal colonization and transmission of S. pyogenes in a male residential ward. Clusters C2 and C3 were genomically diverse, with pairwise SNP differences of 21–45 and 26–58, and emm 11 and mostly emm120, respectively. Clusters C2 and C3, which may have been considered person-to-person transmissions by emm typing, were shown by WGS to be unlikely by integrating pairwise SNP differences with epidemiology.
WGS had higher resolution than emm typing in identifying clusters with recent and ongoing person-to-person transmissions, which allowed implementation of targeted intervention to control the outbreak.
The high rate of chronic hepatitis C (CHC) was one of the key issues of global public health concern. Interferon (IFN)-λ relevant genes were in the antiviral treatment pathway, not only influenced hepatitis C virus (HCV) spontaneous clearance, but also affected the IFN-mediated viral clearance. The aim of this study was to identify the association of interleukin 28B (IL28B), myxovirus resistance A (MxA) gene polymorphisms with HCV spontaneous clearance and therapeutic response in Chinese CHC patients. IL28B and MxA gene genotypes were detected among 231 CHC carriers, 428 subjects with HCV spontaneous clearance and 662 CHC patients with pegylated IFN-α and ribavirin (pegIFN-α/RBV) treatment. Patients with MxA rs2071430 TT genotype were more likely to develop HCV infection chronicity (additive model: odds ratio (OR) 1.22, 95% confidence interval (CI) 1.01–1.48, P = 0.042). IL28B rs1298075 variant genotypes (additive model: OR 0.58, 95% CI 0.34–0.98, P = 0.040) and MxA rs17000900 variant genotypes (additive model: OR 0.54, 95% CI 0.30–0.99, P = 0.048) were less likely to achieve a sustained virological response. The life table indicated that patients with IL28B rs1298075 AG genotype were slower to achieve a viral load <500 copies/ml (P = 0.018). During the treatment, the downward trend in viral load was different among each IL28B rs1298075 genotype, especially in subgroup with a baseline HCV-RNA >106 copies/ml (all P < 0.05). This study illustrated that the carriage of IL28B rs12980275 AA had a positive effect on treatment response to pegIFN-α/RBV among Chinese CHC patients.
High-quality carbon nanotubes (CNTs) and graphene synthesized by chemical vapor deposition (CVD) have unique one- and two-dimensional structures made up of sp2-hybridized carbon atoms and excellent physical and chemical properties. They have shown potential for use in electronics, optoelectronics, energy-storage devices, composites, and sensors. In this article, we review important milestones in these uses of CNTs and graphene produced by CVD, with special emphasis on the latest advances and remaining challenges. The key characteristics and advantages of CNTs and graphene synthesized by CVD for different applications are compared, and future trends in the use of these nanocarbons are discussed.
In this paper, field effect transistors (FET) based on different kinds of non-graphene materials are introduced, which are MoS2, WSe2 and black phosphorus (BP). Those devices have their unique features in fabrication process compared with conventional FETs. Among them, MoS2 FET shows better electrical characteristics by applying a SiO2 protective layer; WSe2 FET is fabricated based on a new low pressure chemical vapor deposition (LPCVD) method; BP FET acquires high on/off ratio and high hole mobility by using a simple dry transfer method. Those novel non-graphene materials inspire new design and fabrication process of basic logic device.
Researches have suggested Mediterranean diet might lower the risk of chronic diseases, but data on skeletal muscle mass (SMM) are limited. This community-based cross-sectional study examined the association between the alternate Mediterranean diet score (aMDS) and SMM in 2230 females and 1059 males aged 40–75 years in Guangzhou, China. General information and habitual dietary information were assessed in face-to-face interviews conducted during 2008–2010 and 3 years later. The aMDS was calculated by summing the dichotomous points for the items of higher intakes of whole grain, vegetables, fruits, legumes, nuts, fish and ratio of MUFA:SFA, lower red meat and moderate ethanol consumption. The SMM of the whole body, limbs, arms and legs were measured using dual-energy X-ray absorptiometry during 2011–2013. After adjusting for potential covariates, higher aMDS was positively associated with skeletal muscle mass index (SMI, SMM/height2, kg/m2) at all of the studied sites in males (all Ptrend<0·05). The multiple covariate-adjusted SMI means were 2·70 % (whole body), 2·65 % (limbs), 2·50 % (arms) and 2·70 % (legs) higher in the high (v. low) category aMDS in males (all P<0·05). In females, the corresponding values were 1·35 % (Ptrend=0·03), 1·05, 0·52 and 1·20 %, (Ptrend>0·05). Age-stratified analyses showed that the favourable associations tended to be more pronounced in the younger subjects aged less than the medians of 59·2 and 62·2 years in females and males (Pinteraction>0·10). In conclusion, the aMDS shows protective associations with SMM in Chinese adults, particularly in male and younger subjects.
I deficiency is a worldwide public health problem. Median urinary I concentration in school-aged children has been used globally as a proxy for all populations. This study aims to determine whether median urinary I concentration of school-aged children is an appropriate indicator of I nutritional status in different adult populations. This is a secondary data analysis of two national I Deficiency Disorder surveys (2011, 2014) and two regional surveys (in coastal areas, 2009, and in high-risk areas, 2009–2014). Population groups included in these surveys were school-aged children (8–10 years), pregnant women, lactating women, women of childbearing age and adults (men and women, 18–45 years). All participants were self-reported healthy without history of thyroid diseases or were not using thyroid medicines. The median urinary I concentration of school-aged children was matched with that of the other population at the county level. The matched populations had similar iodised salt supply, food and water I, food composition and I content in salt. Weak or moderate correlation of median urinary I concentrations was observed between school-aged children and pregnant women and between children and lactating women. However, the agreement was stronger between children and women of childbearing age and between children and adult men and women. The results could be affected by cut-off values, data aggregation level and sample size. Using median urinary I concentration of school-aged children tends to overestimate that of pregnant women and lactating women. Median urinary I concentration of school-aged children can be used for assessing I nutrition in the adult population.
To describe pulsar spin-down, a simple combined torque model, that takes into account both the standard magnetic dipole radiation and the electromagnetic radiation from the 3P2 superfluid vortex neutrons inside neutron star, is presented. Using an ordinary exponential model for the magnetic field decay, we investigate pulsar evolution tracks on the diagram, which is quite different from that of the standard magnetic dipole radiation model, especially when the superfluid torque or field decay become dominate.
Homogeneous equilibrium model (HEM) has been widely used in cavitating flow simulations. The major feature of this model is that a single equation of state (EOS) is proposed to describe the thermal behavior of bubbly liquid, where both kinematic and thermal equilibrium is assumed between two phases. In this paper, the HEM was coupled with multi-relaxation-time lattice Boltzmann model (MRT-LBM) and the acoustic behavior was simulated. Two approaches were applied alternatively: adjusting speed of sound (Buick, J. Phys. A, 2006, 39:13807-13815) and setting real gas EOS. Both approaches result in high accuracy in acoustic speed predictions for different void (gas) volume of fractions. It is demonstrated that LBM could be successfully applied as a Navier-Stokes equation solver for industrial applications. However, further dissipation and dispersion analysis shows that Shan-Chen type approaches of LBM are deficient, especially in large wave-number region.
High-resolution SIMS U–Pb dating of metamorphic zircons of the TTG gneisses, gneissic granitoid and amphibolites of the Lushan terrane, Taihua metamorphic complex, suggests that the metamorphism had taken place at least as early as ~1.96–1.86 Ga. These new dates, along with reference data, demonstrate that the southern and middle terranes of the Trans-North China Orogen had been involved in the continent–continent collision between the Western Block and the Eastern Block of the North China Craton. This orogenic process started as early as 1.96 Ga and lasted as late as 1.80 Ga.
Oocyte-specific linker histone, H1foo, is localized on the oocyte chromosomes during the process of meiotic maturation, and is essential for mouse oocyte maturation. Bovine H1foo has been identified, and its expression profile throughout oocyte maturation and early embryo development has been established. However, it has not been confirmed if H1foo is indispensable during bovine oocyte maturation. Effective siRNAs against H1foo were screened in HeLa cells, and then siRNA was microinjected into bovine oocytes to down-regulate H1foo expression. H1foo overexpression was achieved via mRNA injection. Reverse transcription polymerase chain reaction (RT-PCR) results indicated that H1foo was up-regulated by 200% and down-regulated by 70%. Based on the first polar body extrusion (PB1E) rate, H1foo overexpression apparently promoted meiotic progression. The knockdown of H1foo significantly impaired bovine oocyte maturation compared with H1foo overexpression and control groups (H1foo overexpression = 88.7%, H1foo siRNA = 41.2%, control = 71.2%; P < 0.05). This decrease can be rescued by co-injection of a modified H1foo mRNA that has escaped from the siRNA target. However, the H1e (somatic linker histone) overexpression had no effect on PB1E rate when compared with the control group. Therefore we concluded that H1foo is essential for bovine oocyte maturation and its overexpression stimulates the process.
Proper dry cow management is critical not only for subsequent milk production and fertility but also for mastitis control. A phenomenon of immunosuppression was commonly observed in transition cows, an example being the high susceptibility of the mammary gland during early the dry period to new infectious agents. Polymorphonuclear neutrophils (PMN) play important defence roles in the mammary gland of newly dried cows. One of the bactericidal mechanisms of PMN is through producing reactive oxygen species (ROS), which can be efficiently quantified by chemiluminescence (CL) assay. In the current study, the potential of intramammary application of a commercial Enterococcus faecium SF68 (SF68) product to enhance the local innate immunity of newly dried mammary glands was evaluated based on the CL assay. The preliminary experiments in vitro indicated virtual dose-responsiveness of ROS generation from three different cell preparations, bovine blood PMN, bovine blood PMN pre-conditioned with cow milk, and the post-diapedesis model somatic cells from cow milk, on their exposure to phorbol 12-myristate 13-acetate (PMA), viable SF68, and ultrasonicated SF68, but not dry-heated SF68. Because ultrasonication treatment was found to profoundly enhance the immunogenicity of SF68 in vitro, in the following animal trial, single infusion of either 5 or 10×107 original cfu of ultrasonicated SF68 was randomly applied to the front quarters and phosphate-bufferedsaline (PBS) applied to the rear quarters of each of the four experimental cows on the first day of milk stasis. The results showed that within the first post-infusion week, ultrasonicated SF68 induced a faster and greater (P<0·05) recruitment of PMN into mammary lumen with no apparent local or systemic inflammatory sign. Meanwhile, ultrasonicated SF68 also induced a greater (P<0·05) ROS production in response to PMA challenge by in situ somatic cells of mammary secretion. Taken together, ultrasonicated SF68 modulated ROS generation of bovine neutrophils, and would be a potential enhancer of udder innate immunity in drying-off dairy cows. More thorough work is warranted.
In this paper, low-cost rectifier based on an organic diode for use in organic radio frequency identification (RFID) tags is proposed. Pentacene is the electroactive layer, with 7,7,8,8-tetracyanoquinodimethane (TCNQ) modified low-cost copper (Cu) and aluminum (Al) as the Ohmic and Schottky contacts, respectively. Hole injection barrier between Cu and pentacene can be decreased by forming the self-assembled layers of Cu-TCNQ. The diode shows a high rectification ratio of approximately 2×106 at 5V and the organic diode based rectifier circuit generated a dc output voltage of approximately 2V at 13.56MHz, using an input ac signal with zero-to-peak voltage amplitude of 5 V. The results indicate that chemical modification of the low-cost electrodes could be an efficient way toward low-cost high performance organic electronics devices.
A statistical-thermodynamic model was derived which allows to describe thermodynamic activities in intermetallic compounds with L12-structure as a function of composition and temperature. The energies of formation of the four types of point defects (anti-structure atoms and vacancies on both sublattices) were used as adjustable parameters. The model was applied to the three compounds Ni3Al, Ni3Ga, and Pt3Ga, and it permitted to estimate for the first time the defect formation energies for Ni3Ga and to provide initial estimates for Pt3Ga.
AlGaN/InGaN heterostructure field effect transistors were grown on sapphire by metalorganic chemical vapor deposition. Transmission electron microscopy shows that there are no additional dislocations induced by inserting the InGaN channel while a variation of strain field across the channel is observed. The transistors exhibit good pinch-off characteristics with a threshold voltage of about −2.9 V and a saturation current density of 0.55 A/mm. At room temperature, a peak transconductance of 132 (mS/mm) was obtained for a 1.0 μm-device. Current gain cutoff frequency fT of 9.4 GHz and maximum oscillation frequency fmax of 28.2 GHz were measured for the 1.0 μm-device. As the temperature is increased to 300 °C, the transconductance decreases to 50 mS/mm accompanied by a reduction of saturation current density of 0.24 A/mm due to the enhanced carrier scattering, gate leakage, and drain-source resistance.