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The aim of this study is to assess prevalence of major depressive disorder (MDD), generalized anxiety disorder (GAD), and posttraumatic stress disorder (PTSD) in students of Keyano College 18 months after a wildfire and to determine the predictors of likely MDD, GAD, and PTSD in the respondents.
A quantitative cross-sectional survey was used to collect data through self-administered, paper-based questionnaires to determine likely MDD, GAD, and PTSD using the PHQ 9, GAD-7, and the PTSD Checklist for DSM 5, Part 3, respectively. Data were analyzed with SPSS version 20 (IBM Corp, Armonk, NY) using univariate analysis with chi-square tests.
Eighteen months after the wildfire, the 1-month prevalence rates for MDD, GAD, and PTSD among the college students were 23.4%, 18.7%, and 11.0%, respectively. There were statistically significant associations between multiple sociodemographic variables and the likelihood respondents presented with MDD, GAD, and PTSD 18 months after the wildfire. There were also associations between the likely MDD, GAD, and PTSD and abuse/dependence on alcohol and substances in respondents at 18 months.
Our study has established prevalence rates for MDD, GAD, and PTDS among college students 18 months after the Fort McMurray wildfires. Further studies are needed to explore the impact of college-based mental health interventions on the long-term mental health effects of the wildfires.
The aim of the present study was to investigate the effects of dietary Zn level on growth performance, Zn bioaccumulation, antioxidant capacity and innate immunity in juvenile mud crabs (Scylla paramamosain). Six semi-purified diets were formulated to contain dietary Zn levels of 44·5, 56·9, 68·5, 97·3, 155·6 or 254·7 mg/kg. Dietary Zn level significantly influenced percentage weight gain (PWG), with the highest observed in crabs fed the diet containing 97·3 mg/kg Zn. Tissue Zn concentrations significantly increased as dietary Zn levels increased from 44·5 to 254·7 mg/kg. Retention of Zn in hepatopancreas increased with dietary Zn levels up to 68·5 mg/kg and then significantly decreased. Moreover, inadequate dietary Zn (44·5 and 56·9 mg/kg) reduced antioxidation markers including total superoxide dismutase (SOD) and Cu/Zn SOD activities and total antioxidant level. Crabs fed the diet with 44·5 mg/kg Zn also showed significantly lower expression of genes involved in antioxidant status, such as Cu/Zn SOD, glutathione peroxidase, catalase and thioredoxin than those fed diets containing 68·5 and 97·3 mg/kg Zn. The highest activities of phenoloxidase and alkaline phosphatase were recorded in crabs fed the diets containing 68·5 and 97·3 mg/kg Zn. Expression levels of prophenoloxidase and toll-like receptor 2 were higher in crabs fed the 97·3 mg/kg Zn diet compared with crabs fed the other diets. Based on PWG alone, the optimal dietary Zn level was estimated to be 82·9 mg/kg, with 68·5 to 97·3 mg/kg recommended for maintaining optimal Zn bioaccumulation, oxidation resistance and innate immune response of juvenile mud crabs.
The aim of the present study was to explore the influence of tea consumption on diabetes mellitus in the Chinese population. This multi-centre, cross-sectional study was conducted in eight sites from south, east, north, west and middle regions in China by enrolling 12 017 subjects aged 20–70 years. Socio-demographic and general information was collected by a standardised questionnaire. A standard procedure was used to measure anthropometric characteristics and to obtain blood samples. The diagnosis of diabetes was determined using a standard 75-g oral glucose tolerance test. In the final analysis, 10 825 participants were included and multiple logistic models and interaction effect analysis were applied for assessing the association between tea drinking with diabetes. Compared with non-tea drinkers, the multivariable-adjusted OR for newly diagnosed diabetes were 0·80 (95 % CI 0·67, 0·97), 0·88 (95 % CI 0·71, 1·09) and 0·86 (95 % CI 0·67, 1·11) for daily tea drinkers, occasional tea drinkers and seldom tea drinkers, respectively. Furthermore, drinking tea daily was related to decreased risk of diabetes in females by 32 %, elderly (>45 years) by 24 % and obese (BMI > 30 kg/m2) by 34 %. Moreover, drinking dark tea was associated with reduced risk of diabetes by 45 % (OR 0·55; 95 % CI 0·42, 0·72; P < 0·01). The results imply that drinking tea daily was negatively related to risk of diabetes in female, elderly and obese people. In addition, drinking dark tea was associated with decreased risk of type 2 diabetes mellitus.
Systematic error is one of the major factors that affect positioning accuracy owing to the changeable and complex nature of seawater environments. Based on a Global Navigation Satellite System-acoustic intelligent buoys system, whose acoustic array consists of a series of surface buoys, a single-difference method for underwater dynamic positioning is proposed to eliminate systematic error. Positioning configuration optimisation was addressed using dilution of precision (DOP). A simulation of DOP proved that for the single-difference method, a radiation network with a centre-difference reference point was superior to a regular polygon network. The positioning experiment showed that the novel method could effectively eliminate systematic error, improving vertical positioning accuracy from a metre- to a decimetre scale.
In this work, we studied an atomic layer deposition (ALD) process of ZrO2 with the precursors of tetrakis(dimethylamido)zirconium(IV) and water. We investigated the growth characteristics and mechanism of the ALD ZrO2 in the temperature range of 50–275 °C. Furthermore, the evolutions of film thickness and morphology were studied and discussed. It was found that the growth rate of ZrO2 decreased almost linearly with the increasing temperature from ∼1.81 Å/cycle at 50 °C to ∼0.8 Å/cycle at 225 °C. Interestingly, it was revealed that the growth of ZrO2 films ceased after a certain number of ALD cycles at a temperature higher than 250 °C. We also verified that the crystallinity of ZrO2 evolved with deposition temperature from amorphous to crystalline phase. In addition, the wettability of ZrO2 films was studied, showing a hydrophobic nature.
The microbiota–gut–brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients.
We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD.
The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890.
The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.
Bismuth (Bi)-based photocatalytic materials are widely used in the field of photocatalytic degradation of wastewater. In this study, β-Bi2O3/BiOBr heterojunction photocatalysts were prepared by an in situ chemical transformation method. BiOBr molecules are arrayed to cross each other to form a pore around β-Bi2O3. The prepared photocatalyst had a large specific surface area and excellent adsorption and photocatalytic properties. The β-Bi2O3/BiOBr with a molecular ratio of 11.1% had the highest catalytic activity. The result of a degradation experiment, performed with Rhodamine B (RhB) as the target pollutant, revealed that the degradation rate reached 99.85% after 25 min under visible light irradiation. The pore structure can adsorb contaminants and the heterojunction facilitates the separation of photogenerated electron–hole pairs to enhance the photocatalytic properties. The high adsorption performance and heterojunction achieved higher photocatalytic efficiency. This semiconductor photocatalyst with high adsorption performance provides a new approach to control water pollution.
Severe phase coarsening and separation in Sn–Bi alloys have brought increasing reliability concern in microelectronic packages. In this study, a phase field model is developed to simulate the microstructural evolution and evaluate the change in macroscopic physical properties of the flip chip Cu/Sn58Bi/Cu joint under the conditions of isothermal aging, as well as the coupled loads of elastic stress and electric current stressing. Results show that large-sized Bi-rich phase particles grow up at the expense of small-sized ones. Under the coupled loads, Bi atoms migrate along the electron flow direction, consequently Bi-rich phase segregates to form a Bi-rich phase layer at the anode. The current crowding ratio in the solder decreases rapidly first and then fluctuates slightly with time. Current density and von Mises stress exhibit inhomogeneous distribution, and both of them are higher in the Sn-rich phase than in the Bi-rich phase. Electric current transfers through the Sn-rich phase and detours the Bi-rich phase. As time proceeds, the resistance of the solder joint increases, and the average von Mises stress of the solder joint decreases. The Bi-rich phase coarsens much faster under the coupled loads than under the conditions of isothermal aging.
Carbon nanotubes (CNTs) were added to carbon nanofibers (CNFs) as additives to improve their electrochemical properties. In the present work, CNFs were prepared by using pressurized gyration with polyacrylonitrile as the precursor. The microstructure and electrochemical properties of samples were investigated by scanning electron microscopy and electrochemical workstation, respectively. The results showed that the network structure formed in the fiber, and the fiber diameter decreased with the increase of working pressure. The integral area of cyclic voltammetry curve reached the maximum and the charge/discharge time of constant current charge/discharge curve reached the longest in the case of the CNT concentration is 0.50 wt% and working pressure is 0.2 MPa. At the same time, it exhibited the best electrochemical performance with a specific capacitance of 79 F/g at a current density of 100 mA/g. Compared with the specific capacitance of pure CNFs, the specific capacitance of CNFs with the concentration of CNTs 0.50 wt% increased by about 40%.
Fingerprint-based indoor localisation suffers from influences such as fingerprint pre-collection, environment changes and expending a lot of manpower and time to update the radio map. To solve the problem, we propose an efficient radio map updating algorithm based on K-Means and Gaussian Process Regression (KMGPR). The algorithm builds a Gaussian Process Regression (GPR) predictive model based on a Gaussian mean function and realises the update of the radio map using K-Means. We have conducted experiments to evaluate the performance of the proposed algorithm and results show that GPR using the Gaussian mean function improves localisation accuracy by about 13·76% compared with other functions and KMGPR can reduce the computational complexity by about 7% to 20% with no obvious effects on accuracy.
Previous neuroimaging studies demonstrated that retinal detachment (RD) subjects were associated with abnormal spontaneous brain activities; however, whether the altered interhemispheric functional connectivity (FC) occurred in RD patients remains unknown. The current study tried to explore the alternations of interhemispheric FC of the whole brain in unilateral RD patients using the voxel-mirrored homotopic connectivity (VMHC) method and their connections to clinical features. Methods: We recruited 30 patients with RD (16 males and 14 females) and 30 healthy controls (HCs) (16 males and 14 females) whose age and sex were closely matched. All subjects underwent the rs-fMRI scans. The VMHC method was applied to directly assess the hemispheres’ functional interaction. The VMHC in these brain areas, which could be used as biomarkers to differentiate RD from HC, was identified by the receiver operating characteristic (ROC) curve analyses. The relations between these patients’ clinical features and their mean VMHC signal values in multiple brain regions were calculated by Pearson correlation analysis. Results: RD patients had significantly lower VMHC values than HCs in the bilateral occipital lobe (Brodmann areas, BA 18), bilateral superior temporal gyrus (BA 39), and bilateral cuneus (BA 19). Moreover, the mean VMHC signal values of the bilateral cuneus were in positive correlation with the duration of the RD (r = 0.446, P = 0.013). Conclusion: Our results provided an evidence of disturbed interhemispheric FC in the visual area occurred in RD patients, which might provide some useful information to understand the neural mechanism of RD patients with acute vision loss. Furthermore, the VMHC values might indicate the progress of the RD.
A new plasmonic photocatalyst Ag/Bi7Ta3O18 was fabricated by photodeposition-hydrothermal method. The phase composition, microstructure, surface areas, average pore size, UV-vis diffuse reflection spectra, and photocatalytic activities of composite photocatalysts were investigated in detail. The results of the measurements indicated that the Ag0 nanoparticle successfully loads on the surface of Bi7Ta3O18, and the 0.06 Ag/Bi7Ta3O18 photocatalysts exhibited the best photocatalytic activity for the degradation of Rhodamine B (RhB). The improved photocatalytic activity could be contributed to the localized surface plasmon resonance caused by the collective oscillation of the surface electrons of Ag nanoparticles. Additionally, the photocatalytic reaction mechanism was studied by photoluminescence photocurrent, and electron spin resonance analysis. As a result, the Ag nanoparticles onto the Bi7Ta3O18 surface enlarged the electron–hole separation, and the (˙OH) was the dominated active species of degradation RhB in the photocatalytic process.
Kinetic theory and acoustic measurements have proven that the bulk viscosity associated with the expansion or compression effect cannot be ignored in compressible fluids except for monatomic gases. A new theoretical formula for the bulk viscosity coefficient (BVC)
is derived by the continuum medium methodology, which provides a further understanding of the bulk viscosity, i.e.
is equal to the product of the bulk modulus
and the relaxation time
). The continuum and kinetic theories present consistent results from macro- and microperspectives respectively, only differing in terms of a coefficient. The theoretical predictions of the BVC in diatomic molecules, such as
and CO, show good agreement with the experimental data over a wide range of temperature. In addition, the vibrational contributions to
are controlled by a rapid exponential decrease at high temperatures, while at low temperatures a slow linear increase proceeds for the rotational cases. The relaxation time
, collision number
and ratio of bulk-to-shear viscosities
in the vibrational mode are found to be several orders of magnitude larger than those in the rotational mode.
We demonstrate the combined use of large area depth-profiling dislocation imaging and quantitative composition and strain measurement for a strained Si/SiGe/Si sample based on nondestructive techniques of electron beam-induced current (EBIC) and X-ray diffraction reciprocal space mapping (XRD RSM). Depth and improved spatial resolution is achieved for dislocation imaging in EBIC by using different electron beam energies at a low temperature of ~7 K. Images recorded clearly show dislocations distributed in three regions of the sample: deep dislocation networks concentrated in the “strained” SiGe region, shallow misfit dislocations at the top Si/SiGe interface, and threading dislocations connecting the two regions. Dislocation densities at the top of the sample can be measured directly from the EBIC results. XRD RSM reveals separated peaks, allowing a quantitative measurement of composition and strain corresponding to different layers of different composition ratios. High-resolution scanning transmission electron microscopy cross-section analysis clearly shows the individual composition layers and the dislocation lines in the layers, which supports the EBIC and XRD RSM results.
Worldwide, the number of individuals with dementia is growing in an epidemic manner, with an estimated 35.6 million people affected in 2010 (Prince et al., 2013). With the population aging in Asia, dementia care will become a major public health challenge in this region in the coming decades. Over half of the patients with dementia in the world will live in Asia by 2030. In China alone, a recent review of dementia studies showed that there were 9.2 million dementia patients in 2010 (Chan et al., 2013). These figures are staggering. In many Asian countries, dementia is regarded as a shameful illness, and the local terms for dementia are derogatory. Dementia carries a stigma that may lead to patients’ reluctance in seeking treatment and delay in diagnosis. In addition, local names for dementia frequently conjure up pictures of severe stage of dementia, and may lead to therapeutic nihilism, discouraging mental health professionals from working with elderly patients with dementia. As Asia faces the challenges of a rapidly aging population and provisions of care for growing number of dementia patients, change in local names for dementia has become an issue of attention.
Fine-sized powders of BaSi3Al3O4N5:Eu2+ phosphors with high stability and improved photoluminescence properties were successfully synthesized by the traditional solid-state reaction method under a reductive atmosphere using BaF2-fluxing additives in the raw powder mixture. The produced phosphors had strong blue emission under excitation in ultraviolet (UV) and vacuum ultraviolet (VUV) light, due to the 4f 5d–4f7 transition of Eu2+ ions. X-ray diffraction, scanning electron microscopy, XANES, and the photoluminescence (PL) spectra under UV and VUV were used to characterize the as-received samples. The experimental results showed that the addition of BaF2 flux improved the crystalline regime and the PL properties of the produced phosphors. Most significantly, it allowed control of the particle size and particle size distribution in the final powders but did not jeopardize the high thermal and chemical stability of the phosphors produced. With the modification of the BaF2 flux, the blue-emitting BaSi3Al3O4N5:Eu2+ phosphors will show excellent packing and coating properties and could be a good candidate for the light-emitting diodes and plasma display panels.
Human milk (HM) is rich in oligosaccharides (HMO) that exert prebiotic and anti-infective activities. HM feeding reduces the incidence of rotavirus (RV) infection in infants. Herein, the anti-RV activity of oligosaccharides was tested in an established in vitro system for assessing cellular binding and viral infectivity/replication, and also tested in a newly developed, acute RV infection, in situ piglet model. For the in vitro work, crude HMO isolated from pooled HM, neutral HMO (lacto-N-neotetraose, LNnT; 2′-fucosyllactose) and acidic HMO (aHMO, 3′-sialyllactose, 3′-SL; 6′-sialyllactose, 6′-SL) were tested against the porcine OSU strain and human RV Wa strain. The RV Wa strain was not inhibited by any oligosaccharides. However, the RV OSU strain infectivity was dose-dependently inhibited by sialic acid (SA)-containing HMO. 3′-SL and 6′-SL concordantly inhibited 125I-radiolabelled RV cellular binding and infectivity/replication. For the in situ study, a midline laparotomy was performed on 21-d-old formula-fed piglets and six 10 cm loops of ileum were isolated in situ. Briefly, 2 mg/ml of LNnT, aHMO mixture (40 % 6′-SL/10 % 3′-SL/50 % SA) or media with or without the RV OSU strain (1 × 107 focus-forming units) were injected into the loops and maintained for 6 h. The loops treated with HMO treatments+RV had lower RV replication, as assessed by non-structural protein-4 (NSP4) mRNA expression, than RV-treated loops alone. In conclusion, SA-containing HMO inhibited RV infectivity in vitro; however, both neutral HMO and SA with aHMO decreased NSP4 replication during acute RV infection in situ.
Cu–In–Ga precursor thin films were deposited onto soda lime glass by magnetron cosputtering CuIn and CuGa alloy targets. After that, Cu(In,Ga)Se2(CIGSe) absorbers were formed by selenizing those alloy precursors with Se vapor at 550 °C. The influence of the precursor temperature on the properties of CIGSe thin film was investigated. The results show that a lot of pinholes existed in the CIGSe thin film produced by selenizing the Cu–In–Ga alloy precursor, which was sputtering deposited at ambient temperature. After sputtering substrate temperature of 250 °C was applied, pinholes were avoided. The surface roughness of Cu–In–Ga precursor increased with the increase of sputtering substrate temperature. Due to the volume expansion of selenization process, even the precursor with high surface roughness could be converted to smooth and compact CIGSe thin film.
Energetic electron beam generation from a thin foil target by the ponderomotive force of an ultra-intense circularly polarized laser pulse is investigated. Two-dimensional particle-in-cell (PIC) simulations show that laser pulses with intensity of 1022–1023 Wcm−2 generate about 1–10 GeV electron beams, in agreement with the prediction of one-dimensional theory. When the laser intensity is at 1024–1025 Wcm−2, the beam energy obtained from PIC simulations is lower than the values predicted by the theory. The radiation damping effect is considered, which is found to become important for the laser intensity higher than 1025 Wcm−2. The effect of laser focus positions is also discussed.