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Anatase phase NOx/S6+–TiO2 (x= 0, 1) film with high solar-driven activity has been successfully prepared via electro-assisted oxidation processes. The morphological and structural properties of the film were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction, while the optical property was detected by UV-vis-NIR absorption spectroscopy. The results showed that the NOx/S6+–TiO2 film was composed of “flower-like” microvoids structure and displayed broad and strong optical absorption at around 544 and 1500 nm. Transient photocurrent response, photoluminescence spectroscopy, and electrochemical impedance spectroscopy indicated that the generation and separation of photogenerated charges were significantly enhanced under simulated solar irradiation. The NOx/S6+–TiO2 film exhibited excellent photoelectrocatalytic activity for the degradation of methyl orange (MO), and the decoloration rate and TOC removal respectively reached 98.97 and 59.44% at 20 min under solar irradiation. The film still had good stability after reusing ten times. Furthermore, a possible mechanism of photoelectrocatalysis was suggested in MO degradation by using NOx/S6+–TiO2 film.
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.
A new band-reject frequency-selective surface (FSS) based on dual-band near-zero refractive index metamaterial (ZIM) design is presented in this paper. Consisting of a planar array of complementary dual-layer symmetry resonant ring, the proposed FSS exhibits a high-selective band-reject filtering response. From the viewpoint of effective medium, the subwavelength FSS is characterized by near-zero effective magnetic permeability and near-zero effective electric permittivity in two different operational bands, respectively. The corresponding resonant behavior and E-field distributions are analyzed in detail. A prototype of the proposed FSS working in X-band is fabricated and measured. The simulation and experiment results verify the effectiveness and correctness of the ZIM-based design method.
Human papillomavirus (HPV) has been identified as etiologic agent of various cancers for both men and women. However, HPV vaccine has not been recommended for men in China by far. To provide more evidences to promote HPV vaccination among males at high-risk of infection, this study investigated genital HPV genotypes among male attendees of sexually transmitted disease (STD) clinic. Male attendees (⩾18 years old) were recruited from STD clinic of Beijing Ditan Hospital. Data on sociodemographic characteristics and self-reported sexual behaviors were collected based on questionnaire. Genital swab specimens were collected for HPV genotypes. Finally, a total of 198 eligible participants were included in the study. Nearly half of them were infected with at least one type of HPV. The prevalence of genital infection among participants with only heterosexual behaviors (50·91%, 56/110) was significantly higher than those with only homosexual behaviors (36·36%, 32/88) (P < 0·001). However, the distribution pattern of the most frequently observed HPV subtypes were found to be similar between these two subgroups. HPV31, HPV18, HPV16 and HPV58 were the most frequently identified high-risk types and HPV11, HPV6, HPV81 and HPV61 were the most frequently observed low-risk types. Our results, although need further verification by larger sample size, suggested that currently available HPV vaccines covered most prevalent HPV types observed in Chinese men. As HPV vaccine has been approved for application in females in China, molecular epidemiological studies and intervention studies among high-risk males should be promoted as well.
We combine radio-echo sounding ice thickness data from the BEDMAP Project database and the PCMEGA (Prince Charles Mountains Expedition of Germany and Australia) dataset to generate a new ice thickness grid for the southern limit region of the Amery Ice Shelf, East Antarctica. We then reassess the mass balance of the central portion of the Lambert-Amery system, incorporating flow information derived from synthetic aperture radar interferometry (InSAR) and a modeled surface mass-balance dataset based on regional atmospheric modeling. Our analysis reveals that Mellor and Fisher Glaciers are approximately in balance to the level of our measurement uncertainty, while Lambert Glacier has a positive imbalance of 4.2 ±2.3 Gta1. The mass budget for the whole Lambert Glacier basin is approximately in balance, and the average basal melt rate in the downstream section of the ice shelf is 5.1 ± 3.0 m a-1. Our results differ substantially from other recent estimates using hydrostatically derived ice thickness data.
Leucine plays an important role in promoting muscle protein synthesis and muscle remodelling. However, what percentage of leucine is appropriate in creep feed and what proteome profile alterations are caused by dietary leucine in the skeletal muscle of piglets remain elusive. In this case, we applied isobaric tags for relative and absolute quantitation to analyse the proteome profile of the longissimus dorsi muscles of weanling piglets fed a normal leucine diet (NL; 1·66 % leucine) and a high-leucine diet (HL; 2·1 % leucine). We identified 157 differentially expressed proteins between these two groups. Bioinformatics analysis of these proteins exhibited the suppression of oxidative phosphorylation and fatty acid β-oxidation, as well as the activation of glycolysis, in the HL group. For further confirmation, we identified that SDHB, ATP5F1, ACADM and HADHB were significantly down-regulated (P<0·01, except ATP5F1, P<0·05), whereas the glycolytic enzyme pyruvate kinase was significantly up-regulated (P<0·05) in the HL group. We also show that enhanced muscle protein synthesis and the transition from slow-to-fast fibres are altered by leucine. Together, these results indicate that leucine may alter energy metabolism and promote slow-to-fast transitions in the skeletal muscle of weanling piglets.
Low-protein diet plus ketoacids (LPD+KA) has been reported to decrease proteinuria in patients with chronic kidney diseases (CKD). However, the mechanisms have not been clarified. As over-activation of intrarenal renin–angiotensin system (RAS) has been shown to play a key role in the progression of CKD, the current study was performed to investigate the direct effects of LPD+KA on intrarenal RAS, independently of renal haemodynamics. In this study, 3/4 subtotal renal ablated rats were fed 18 % normal-protein diet (Nx-NPD), 6 % low-protein diet (Nx-LPD) or 5 % low-protein diet plus 1 % ketoacids (Nx-LPD+KA) for 12 weeks. Sham-operated rats fed NPD served as controls. The level of proteinuria and expression of renin, angiotensin II (AngII) and its type 1 receptors (AT1R) in the renal cortex were markedly higher in Nx-NPD group than in the sham group. LPD+KA significantly decreased the proteinuria and inhibited intrarenal RAS activation. To exclude renal haemodynamic impact on intrarenal RAS, the serum samples derived from the different groups were added to the culture medium of mesangial cells. It showed that the serum from Nx-NPD directly induced higher expression of AngII, AT1R, fibronectin and transforming growth factor-β1 in the mesangial cells than in the control group. Nx-LPD+KA serum significantly inhibited these abnormalities. Then, proteomics and biochemical detection suggested that the mechanisms underlying these beneficial effects of LPD+KA might be amelioration of the nutritional metabolic disorders and oxidative stress. In conclusion, LPD+KA could directly inhibit the intrarenal RAS activation, independently of renal haemodynamics, thus attenuating the proteinuria in CKD rats.
Given the importance of voice in ethical leadership theory, we analyze the relationship of ethical leadership to employee voice and the relationship of voice to exit intentions. Building on the theory of work engagement, we further hypothesize that cognitive engagement mediates these proposed relationships. To test these propositions, we conduct a field study to relate ethical leadership of supervisors, measured at time 1, to employees’ cognitive job engagement, measured at time 2. The analyses show that the relationship between these variables can account for supervisory ethical leadership’s association with employee voice and exit intentions. In a supplementary study using a different sample, we find that supervisory ethical leadership is related to exit intentions through voice. We discuss how these findings contribute to the literature on ethical leadership, employee voice, and exit.
Rapid solidification of Al30Si70 alloy was studied via electromagnetic levitation technique. The solidification kinetics and the morphology of the solidification front of the Si phase were analyzed in situ by using a high-speed video camera and subsequent microstructural analysis of as-solidified samples. It shows that solidification of the sample always starts from one point. After that, nucleation continues to proceed at the interface front during growth. The morphology of primary Si transforms from faceted wafer to nonfaceted equiaxed grain and the grain size decreases with increase of undercooling. At small undercooling, the growth velocity of primary Si decreases with time and the floated Si wafers have a trend to agglomerate, while at large undercooling, the nucleation rate decreases with time, which are explained by the fact that silicon content, undercooling and density at the solid–liquid interface change with time in solidification. Finally, the nucleation rate and growth velocity were discussed in combination of classical theory.
In this work, fluorescent Bacillus subtilis (B. subtilis) cells were developed as probes for imaging applications and to explore behaviorial interaction between B. subtilis and Staphylococcus aureus (S. aureus). A novel biological strategy of coupling intracellular biochemical reactions for controllable biosynthesis of CdSe quantum dots by living B. subtilis cells was demonstrated, through which highly luminant and photostable fluorescent B. subtilis cells were achieved with good uniformity. With the help of the obtained fluorescent B. subtilis cells probes, S. aureus cells responded to co-cultured B. subtilis and to aggregate. The degree of aggregation was calculated and nonlinearly fitted to a polynomial model. Systematic investigations of their interactions implied that B. subtilis cells inhibit the growth of neighboring S. aureus cells, and this inhibition was affected by both the growth stage and the amount of surrounding B. subtilis cells. Compared to traditional methods of studying bacterial interaction between two species, such as solid culture medium colony observation and imaging mass spectrometry detection, the procedures were more simple, vivid, and photostable due to the efficient fluorescence intralabeling with less influence on the cells’ surface, which might provide a new paradigm for future visualization of microbial behavior.
To explore the prevalence and determinants of chronic post-traumatic stress disorder (PTSD) among flood victims.
A cross-sectional survey was carried out in 2014 among individuals who had experienced the 1998 floods and had been diagnosed with PTSD in 1999 in Hunan, China. Cluster sampling was used to select subjects from the areas that had been surveyed in 1999. PTSD was diagnosed according to DSM-IV criteria, social support was measured according to a Social Support Rating Scale, coping style was measured according to a Simplified Coping Style Questionnaire, and personality was measured by use of the revised Eysenck Personality Questionnaire Short Scale for Chinese. Data were collected through face-to-face interviews by use of a structured questionnaire. Multivariate logistic regression analysis was used to reveal the determinants of chronic PTSD.
A total of 123 subjects were interviewed, 17 of whom (14.4%) were diagnosed with chronic PTSD. Chronic PTSD was significantly associated with disaster stressors (odds ratio [OR]: 1.74; 95% confidence interval [CI]: 1.22-2.47), nervousness (OR: 1.09; 95% CI: 1.01-1.17), and social support (OR: 0.85; 95 CI%: 0.74-0.98).
Chronic PTSD in flood victims is significantly associated with disaster stressors, nervousness, and social support. These factors may play important roles in identifying persons at high risk of chronic PTSD. (Disaster Med Public Health Preparedness. 2015;9:504–508)
We investigated the effect of human induced pluripotent stem cell (hiPS) medium on porcine somatic cell nuclear transfer and bovine in vitro fertilized early blastocysts, in comparison with North Carolina State University (NCSU)-37 medium and in vitro culture (IVC)-II medium. After 2 days of culture, the diameter of the portion of the blastocyst that was extruded from the zona pellucid dramatically differed between porcine blastocysts cultured in hiPS medium and those cultured in NCSU-37 medium (221.47 ± 38.94 μm versus 481.87 ± 40.61 μm, P < 0.01). Moreover, the diameter of the portion of the blastocyst significantly differed between bovine blastocysts cultured in hiPS medium and those cultured in IVC-II medium (150.30 ± 29.49 μm versus 195.58 ± 41.59 μm, P < 0.01). Furthermore, the total number of cells per porcine and bovine blastocyst was more than two-fold higher in blastocysts cultured in hiPS medium than in those cultured in NCSU-37 medium (44.33 ± 5.28 and 143.33 ± 16.05, P < 0.01) or IVC-II medium (172.12 ± 45.08 and 604.83 ± 242.64, P < 0.01), respectively. These results indicate that hiPS medium markedly improves the quality of porcine and bovine blastocysts.
Cu and Cu–Al alloys with different stacking fault energies (SFEs) were processed using rolling and the Split Hopkinson pressure bar followed by rolling. The effect of strain rate on the microstructures and mechanical properties of the alloys were investigated using x-ray diffraction analyses, transmission electron microscopy, and tensile tests. Tensile testing results demonstrated that the strength and ductility of the samples increased simultaneously with decreasing SFE. Microstructural observations indicated that the average grain size of the samples decreased with decreasing SFE, but the twin and dislocation densities increased. With decreasing SFE, twinning becomes the dominant deformation mechanism. Our findings indicated that the SFEs significantly affect the strength and ductility of the materials because they play a key role in determining the deformation mechanism. Decreasing the SFE of Cu alloys has proved to be the optimum method to improve the ductility without compromising the strength of the material.
Seed protein content is one of the most important traits controlled by quantitative trait loci (QTLs) in soybean. In this study, a Glycine soja accession (ZYD2738) was crossed with two elite cultivars Jidou 12 and Jidou 9 separately and subsequently the resulting F2:3 populations were used to identify QTLs associated with seed protein content. Protein contents in either population appeared to have a normal distribution with transgressive segregation. A total of five QTLs associated with high protein content were identified and mapped to chromosomes 2, 6, 13, 18 and 20, respectively. Of these QTLs, three (qPRO_2_1, qPRO_13_1 and qPRO_20_1) were identified in the same region in both the populations, whereas the other two (qPRO_6_1 and qPRO_18_1) were mapped in two different regions. qPRO_2_1 appears to be a novel protein QTL. qPRO_6_1, qPRO_18_1 and qPRO_20_1 had additive effects on seed protein content, while qPRO_13_1 had an over-dominant effect on seed protein content. These QTLs and their linked markers could serve as effective tools for marker-assisted selection to increase seed protein content.
Schizophrenia (SCZ) and bipolar disorder (BD) are common psychotic disorders, which show some overlaps in genetic aetiology. Researchers have conducted a number of studies to investigate the relationship between SCZ and the 1354C/T genetic polymorphism of 5-hydroxytryptamine receptor 2A (HTR2A–1354C/T), as well as the associations between BD and the HTR2A–1354C/T polymorphism. However, the results were conflicting. To provide a more robust estimate about the effects of the HTR2A–1354C/T polymorphism on the risk of these two psychotic disorders, we performed this meta-analysis.
We used the pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) to investigate the relationships between SCZ and the 1354C/T polymorphism of HTR2A, as well as the associations between BD and HTR2A–1354C/T. Publication bias was tested by Begg's test and inverted funnel plot, and heterogeneity was checked by Cochran's Q statistic and the inconsistency index (I2).
Eight studies were concerned with SCZ, analysing a cumulative total of 2953 cases and 3153 controls; six papers studied BD, using a total of 923 cases and 928 controls. There was no significant association found between HTR2A–1354C/T and SCZ in the overall population (T allele vs. C allele, OR = 1.035, 95% CI 0.912–1.175, p = 0.596) or in the subgroups Caucasian population and Asian population. Moreover, there was no significant association between the HTR2A–1354C/T polymorphism and BD in the overall population (T allele vs. C allele, OR = 1.038, 95% CI = 0.607–1.772, p = 0.892).
On the basis of these results, the HTR2A–1354C/T polymorphism is unlikely to be a risk factor for SCZ and BD.
We have measured electron drift in amorphous silicon-germanium nip photodiodes using the photocarrier time-of-flight technique. The samples show electron deep-trapping shortly after photogeneration, which is generally attributed to capture by a neutral dangling bond (D0) to form a negatively charged center (D-). An unusual feature is that electron re-emission from the trap is also clearly seen in the transients. Temperature-dependent measurements on the emission yield an activation energy of about 0.8 eV and the remarkably large value of 1015 Hz for the emission prefactor frequency. We also compiled results on electron emission from deep traps in a-Si:H, a-SiGe:H, and a-SiC:H from six previous publications. Collectively, these measurements exhibit "Meyer Neldel" behavior for electron emission over a range of activation energies from 0.2–0.8 eV and a prefactor range extending over nine decades, from 106 to 1015 Hz. The Meyer-Neldel behavior is consistent with the predictions of the multi-excitation entropy model. We extract a ionization entropy of 20kB from the measurements, which is very large compared to crystal silicon. We discuss this result in terms of a bond charge model.
This paper presents a seven-link dynamic walking model that is more close to human beings than other passivity-based dynamic walking models. We add hip actuation, upper body, flat feet, and ankle joints with torsional springs to the model. Walking sequence of flat-feet walkers has several substreams, which forms bipedal walking with dynamic series of phases. We investigate the effects of ankle stiffness on gait selection and evaluate different gaits in walking velocity, efficiency, and stability. Experimental results indicate that ankle stiffness plays different roles in different gaits and the gaits, which are more close to human walking with moderate speed, achieve better motion characteristics.
The N95 respirator is one type that is recommended by the World Health Organization and the Centers for Disease Control and Prevention (CDC) to prevent inhalation of droplets that may act to transmit respiratory pathogens. However, the reliability of this respirator to prevent transmission is dependent on how well it is fitted to the wearer. For ill-fitting respirators, the average penetration by ambient aerosol was found to be 33%, compared with 4% for well-fitting respirators. Such penetration or leakage may be caused by the gap between the respirator and the wearer's face. Therefore, formal fit testing should be carried out prior to the use of N95 respirators. Quantitative fit testing measures “the adequacy of respirator fit by numerically measuring the amount of leakage into the respirator” using an electronic device.
An integrated data acquisition/actuator control system is developed to conduct experiments investigating the fundamental dynamics for different operating conditions in an electrospinning system. The relation between measured variables (fiber current, whipping angle, jet length, and expulsion cone volume) to the resulting fiber diameter distribution is analyzed.
Mixed solvent of ethanol and water using FeSO4⋅7H2O and (NH2)2CS as precursors with polyvinylpyrrolidone as surfactant was used to synthesize cubic FeS2 (pyrite) crystals. Crystalline phase and surface morphologies of the crystals were characterized by X-ray diffraction and scanning electron microscopy, respectively. Volume ratio of solvent, reaction temperature, reaction time, and sulfur source were found to be the key parameters for the formation of pure pyrite crystals. Optimal micron-size pyrite crystals were successfully grown from a mixed solvent of ethanol and water with a volume ratio of 3:2, heated to a reaction temperature of 180 °C, and maintained for 36 h with thiourea as the sulfur source.