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The hierarchical Au-loaded SnO2 nanoflowers were synthesized using a new developed self-reductive hydrothermal method, of which the gas-sensing properties were enhanced significantly. The SnO2 hierarchical nanoflowers were composed of well-defined nanosheets with a specific surface area of around 84 m2/g. Gas sensors made of pure and Au-doped SnO2 were fabricated, and their gas-sensing properties were characterized. The 1.0 at.% Au-loaded SnO2 sensor prepared by the new developed self-reductive method showed much more excellent selectivity toward ethanol at 200 °C than the one prepared with the conventional hydrothermal method. Its response to ethanol was around 3 times higher than that of the pure SnO2 sensor. A very wide detection range of 1–500 ppm for ethanol, good repeatability, and long-term stability were also approved.
The BioCD is a spinning biochip that uses quadrature laser interferometry to detect captured protein on the disc surface. We describe the detection limits of protein binding on this optical biosensor. The fundamental metrology limit is 1 picometer for a single 100-micron diameter spot. Under assay conditions for prostate specific antigen, we can detect 25 pg/ml at 10 assays per disc.
Molecular interferometric imaging (MI2) is a label-free optical biosensor that combines common-path interferometry with shot-noise limited characteristics of a CCD array detector to detect protein binding to surfaces. In the metrology limit, it has achieved roughness-limited surface height resolution of 15 pm per 0.4 micron pixel, corresponding to a scaling mass sensitivity of 7 fg/mm, and a molecular resolution of about 15 IgG molecules per pixel. We have applied MI2 to detect cytokine interleukin-5 at a concentration detection limit of 50 pg/mL with a sandwich immunoassay. Real-time binding assays with MI2 enable the study of reaction kinetics, with a scaling mass sensitivity of 2 pg/mm under 7x magnification. Real-time MI2 measurements of anti-rabbit IgG against rabbit IgG were compared with results from surface plasmon resonance, with identical association rate constants at 5x103 M-1sec-1.
Radiocarbon (14C) has become a unique and powerful tracer in source apportionment of atmospheric carbonaceous particles. In this study, the Asia Pacific Economic Cooperation summit (APEC) held in Beijing in 2014 was used as a demonstration to research the source apportionment of atmosphere PM2.5. We used a 200 kV single stage accelerator mass spectrometer recently completed at China Institute of Atomic Energy (CIAE). The PM2.5 samples related to above case were collected, and the characteristics of radiocarbon in organic carbon (OC) and elemental carbon (EC) in samples were analyzed using the AMS. The results show that the Before-APEC pollution emission mode is different from the During-APEC and After-APEC pollution emission modes. For Before-APEC, During-APEC and After-APEC, the average values of fossil carbon fraction of OC are 0.463, 0.431 and 0.615, respectively, and those of EC are 0.644, 0.561 and 0.687. The fossil source contributions of traffic activities using fossil fuels to OC and EC are 15.8 % and 21.9 %, respectively. The fossil source contributions of industrial activities to OC and EC are 38.0 % and 8.2 %, respectively. It is about 7–10 days that is needed to take to regenerate the PM2.5 pollution caused by human activities.
Many components in diet have regulated oxidative stress, inflammatory reaction and even balance estrogen levels. Because these factors are closely associated with depressive symptoms in postmenopausal women, it is considered that dietary factors are able to prevent and control depressive symptoms. On the other hand, dietary pattern that considers the correlations and synergies between foods and nutrients, is expected to have a greater impact on disease risk. The aim of this study is to evaluate whether dietary patterns are associated with depressive symptoms in Chinese postmenopausal women.
A cross-sectional study of 2051 postmenopausal women (mean age: 58.8±7.4 years) was conducted in Tianjin, China. Dietary consumption was assessed by a valid self-administered food frequency questionnaire. Principal component analysis was used to derive three major dietary patterns: “healthy”, “sweets” and “Traditional Tianjin” from 88 food items. Depressive symptoms were assessed using the Zung Self-Rating Depression Scale, and cut-off point of 48 indicating serious depressive symptoms. The associations between quartile of dietary patterns and depressive symptoms were assessed by using multiple logistic regression analysis.
The multivariable-adjusted odds ratios (95% confidence intervals) of having depressive symptoms for increasing quartile of dietary patterns were as follows: “healthy”, 1.00, 0.79(0.49–1.28), 0.62(0.37–1.04), and 0.57(0.33–0.97); “sweets”,1.00, 0.75(0.42–1.3), 1.08(0.64–1.81) and 1.66(1.03–2.71); “Traditional Tianjin”, 1.00, 1.02(0.58–1.79), 0.96 (0.54–1.71) and 2.53(1.58–4.16), respectively.
The present study demonstrated that a healthy dietary pattern was inversely associated with depressive symptoms. On the contrary, greater adherence to sweets and Traditional Tianjin dietary patterns were associated with a higher prevalence of depressive symptoms.
We assessed inheritance of resistance to sugarcane brown rust (Puccinia melanocephala) in selfing F1 populations of wild sugarcane germplasm Erianthus rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’. We tested parent and selfing F1 individuals for the brown rust resistance gene, Bru1, that has been shown to confer resistance to brown rust in sugarcane. The Bru1 gene was not detected in E. rockii ‘Yundian 95-19’, E. rockii ‘Yundian 95-20’ or their selfing F1 individuals, and we found there was segregation of resistance in the two selfing F1 populations (segregation ratio: 3:1). The results confirmed resistance in E. rockii ‘Yundian 95-19’ and E. rockii ‘Yundian 95-20’ to sugarcane brown rust is controlled by a novel, single dominant gene.
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
Geochronological, major and trace element, and Sr–Nd–Hf isotopic data are reported for the monzonitic rocks of the Fushan pluton in the Taihang Mountains, central North China Craton, in order to investigate their sources, petrogenesis and tectonic implications. Zircon U–Pb dating results reveal that the Fushan pluton was emplaced during the Early Cretaceous (∼126–124 Ma). The monzonites and quartz monzonites are mainly characterized by calc-alkaline and magnesian features and display light rare earth element (LREE) enrichment and flat heavy REE (HREE) patterns with slightly positive Eu anomalies. They have similar whole-rock initial 87Sr/86Sr ratios (0.70653–0.70819), εNd(t) values (−13.6 to −18.6) and zircon εHf(t) values (−21.8 to −17.3). The primary magma of the Fushan pluton was derived from the partial melting of a spinel-facies amphibole-bearing ancient enriched lithospheric mantle. The monzonitic rocks also have high Ba–Sr and low Y and Yb contents, with high Sr/Y and La/Yb ratios. These geochemical features of monzonitic rocks are not only inherited from the magma source but also significantly enhanced by crystal fractionation during magmatic evolution; e.g. hornblende fractionation increased the Ba–Sr concentrations and Sr/Y ratios. During the Early Cretaceous, the slab sinking and roll-back of the Palaeo-Pacific Plate could have created an ancient big mantle wedge beneath East Asia and induced a lithospheric extensional process in the central North China Craton within an intracontinental setting.
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.
The second home-made single stage accelerator mass spectrometer (SSAMS) system dedicated to radiocarbon (14C) measurements was built after the first SSAMS system was moved to Guangxi Normal University. With some improvements to the second SSAMS system, the performance has been improved. With the conditions of total ion energy of 200KeV, ions charge states of 1+ and helium as stripper gas, 14C measurements with precision of 0.5% and a background level of 0.5 pMC were achieved. Details of the system and the experimental performance are given here.
In this paper, based on a novel multimode stub-loaded resonator, a second-order quad-band bandpass filter (BPF) with mixed electric and magnetic coupling is presented. The electric coupling and magnetic coupling are realized by arranging the parallel coupled lines and the grounded stub, respectively. Eight controllable resonant modes can be simultaneously excited and easily tuned. Eight transmission zeros are created, enhancing the passband selectivity. In addition, the bandwidths can be controlled independently by adjusting the coupling strength. A quad-band BPF centering at 0.67, 1.51, 2.84, 3.58 GHz with respective 3 dB fractional bandwidths of 13.4, 15.6, 9.2, 11.5% is designed, fabricated, and measured. The filter is compact with overall size 0.058λg × 0.13λg. The measured results show a good consistence with the simulated ones.
Cellulitis is a common infection of the skin and soft tissue. Susceptibility to cellulitis is related to microorganism virulence, the host immunity status and environmental factors. This retrospective study from 2001 to 2013 investigated relationships between the monthly incidence rate of cellulitis and meteorological factors using data from the Taiwanese Health Insurance Dataset and the Taiwanese Central Weather Bureau. Meteorological data included temperature, hours of sunshine, relative humidity, total rainfall and total number of rainy days. In otal, 195 841 patients were diagnosed with cellulitis and the incidence rate was strongly correlated with temperature (γS = 0.84, P < 0.001), total sunshine hours (γS = 0.65, P < 0.001) and total rainfall (γS = 0.53, P < 0.001). The incidence rate of cellulitis increased by 3.47/100 000 cases for every 1° elevation in environmental temperature. Our results may assist clinicians in educating the public of the increased risk of cellulitis during warm seasons and possible predisposing environmental factors for infection.
Whether borderline personality disorder (BPD) and bipolar disorder are the same or different disorders lacks consistency.
To detect whether grey matter volume (GMV) and grey matter density (GMD) alterations show any similarities or differences between BPD and bipolar disorder.
Web-based publication databases were searched to conduct a meta-analysis of all voxel-based studies that compared BPD or bipolar disorder with healthy controls. We included 13 BPD studies (395 patients with BPD and 415 healthy controls) and 47 bipolar disorder studies (2111 patients with bipolar disorder and 3261 healthy controls). Peak coordinates from clusters with significant group differences were extracted. Effect-size signed differential mapping meta-analysis was performed to analyse peak coordinates of clusters and thresholds (P < 0.005, uncorrected). Conjunction analyses identified regions in which disorders showed common patterns of volumetric alteration. Correlation analyses were also performed.
Patients with BPD showed decreased GMV and GMD in the bilateral medial prefrontal cortex network (mPFC), bilateral amygdala and right parahippocampal gyrus; patients with bipolar disorder showed decreased GMV and GMD in the bilateral medial orbital frontal cortex (mOFC), right insula and right thalamus, and increased GMV and GMD in the right putamen. Multi-modal analysis indicated smaller volumes in both disorders in clusters in the right medial orbital frontal cortex. Decreased bilateral mPFC in BPD was partly mediated by patient age. Increased GMV and GMD of the right putamen was positively correlated with Young Mania Rating Scale scores in bipolar disorder.
Our results show different patterns of GMV and GMD alteration and do not support the hypothesis that bipolar disorder and BPD are on the same affective spectrum.
Limited information is available on the prevalence and effect of hypertriglyceridaemic–waist (HTGW) phenotype on the risk of type 2 diabetes mellitus (T2DM) in rural populations.
In the present cross-sectional study, we investigated the prevalence of the HTGW phenotype and T2DM and the strength of their association among rural adults in China.
HTGW was defined as TAG >1·7 mmol/l and waist circumference (WC) ≥90 cm for males and ≥80 cm for females. Logistic regression analysis yielded adjusted odds ratios (aOR) relating risk of T2DM with HTGW.
Adults (n 12 345) aged 22·83–92·58 years were recruited from July to August of 2013 and July to August of 2014 from a rural area of Henan Province in China.
The prevalence of HTGW and T2DM was 23·71 % (males: 15·35 %; females: 28·88 %) and 11·79 % (males: 11·15 %; females: 12·18 %), respectively. After adjustment for sex, age, smoking, alcohol drinking, blood pressure, physical activity and diabetic family history, the risk of T2DM (aOR; 95 % CI) was increased with HTGW (v. normal TAG and WC: 3·23; CI 2·53, 4·13; males: 3·37; 2·30, 4·92; females: 3·41; 2·39, 4·85). The risk of T2DM with BMI≥28·0 kg/m2, simple enlarged WC and simple disorders of lipid metabolism showed an increasing tendency (aOR=1·31, 1·75 and 2·32).
The prevalence of HTGW and T2DM has reached an alarming level among rural Chinese people, and HTGW is a significant risk factor for T2DM.
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.
Student engagement is a relatively new construct that describes concepts as varied as classroom behaviors, emotional reactions, motivational beliefs, self-regulatory processes, metacognitive strategies, school belonging and interactions with instructional materials. This chapter reviews a variety of methods to measure student engagement including self-report surveys, teacher ratings, interviews, administrative data, observations, experience sampling methods, and real-time measures. The authors outline the strengths and limitations of each method. Next, we present two examples from our own research on approaches to measuring engagement. The goal of these cases is to illustrate how we have addressed some of the challenges with measurement, as well as showing the importance of choosing a measurement technique that aligns with the research questions. First, we describe the results of a qualitative study to develop a new subject-specific measure of engagement. Next, information on the predictive validity of an observational measure to assess engagement at the class-level is presented. The chapter concludes with a discussion of measurement limitations, future directions, and implications for policy and practice.
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.
Direct numerical simulation is conducted to uncover the response of a supersonic turbulent boundary layer to streamwise concave curvature and the related physical mechanisms at a Mach number of 2.95. Streamwise variations of mean flow properties, turbulence statistics and turbulent structures are analysed. A method to define the boundary layer thickness based on the principal strain rate is proposed, which is applicable for boundary layers subjected to wall-normal pressure and velocity gradients. While the wall friction grows with the wall turning, the friction velocity decreases. A logarithmic region with constant slope exists in the concave boundary layer. However, with smaller slope, it is located lower than that of the flat boundary layer. Streamwise varying trends of the velocity and the principal strain rate within different wall-normal regions are different. The turbulence level is promoted by the concave curvature. Due to the increased turbulence generation in the outer layer, secondary bumps are noted in the profiles of streamwise and spanwise turbulence intensity. Peak positions in profiles of wall-normal turbulence intensity and Reynolds shear stress are pushed outward because of the same reason. Attributed to the Görtler instability, the streamwise extended vortices within the hairpin packets are intensified and more vortices are generated. Through accumulations of these vortices with a similar sense of rotation, large-scale streamwise roll cells are formed. Originated from the very large-scale motions and by promoting the ejection, sweep and spanwise events, the formation of large-scale streamwise roll cells is the physical cause of the alterations of the mean properties and turbulence statistics. The roll cells further give rise to the vortex generation. The large number of hairpin vortices formed in the near-wall region lead to the improved wall-normal correlation of turbulence in the concave boundary layer.
This paper presents new LA-ICP-MS zircon U–Pb chronology, whole-rock geochemical and zircon Hf isotopic data for the felsic lavas of the Huili Group from the southwestern Yangtze Block. LA-ICP-MS zircon U–Pb dating shows that these rocks were emplaced in Late Mesoproterozoic time (∼1028 to 1019 Ma). Relative to typical I-type and S-type granitoids, all the samples are characterized by low Sr and Eu, and high high-field-strength element contents, high TFeO/MgO, enriched rare earth element compositions and negative Eu anomalies, indicating that they share the geochemical signatures of A-type granitoid. They can be further divided into two groups: Group I and Group II. Group I are A1-type felsic rocks and were produced by fractional crystallization of alkaline basaltic magmas. The Group II felsic lavas belong to the A2-type and were derived by partial melting of a crustal source with mixing of mantle-derived magmas. Both Group I and Group II felsic lavas may erupt in a continental back-arc setting. The coexistence of A1- and A2-type rocks in the southwestern Yangtze Block suggests that they can occur in the same tectonic setting.