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To solve the poor cyclability of faradic supercapacitors (SCs), the authors reported a unique porous carbon (PC) coating with “gap shell” structure on carbon fiber cloth (CFC)/NiS2 materials. This gap shell PC coating was fabricated by combining atomic layer deposition (ALD) Al2O3 and molecular layer deposition alucone, followed by carbonization and etching. The as-prepared CFC/NiS2/PC composites were directly used as binder-free electrodes for SCs. Benefited from its novel nanostructure, the CFC/NiS2/PC electrode shows a large specific capacitance of 1034.6 F/g at 1 A/g and considerable rate capability of 67% capacitance, retaining ratio within 1–20 A/g. The cyclability of the CFC/NiS2/PC electrode is enhanced by 50% relative to the mere CFC/NiS2 after 2000 cycles, which is attributed to the gap and electrically conductive PC coating. Hence, this work provides a promising approach to design gap shell layer for improved cyclability of faradic SCs and other practical applications in energy storage electronics.
The static data obtained from user research are not sufficient to accurately reflect the change of the user's needs and capabilities in different contexts. Not paying enough attention to the economic feasibility of design solutions makes inclusive design face challenges in commercialization. In this paper, the user's demand is regarded as a function of the dynamic interaction between the user's characteristics and the environment. The inclusion problem is defined from an economic perspective. By distinguishing the stages before and after the delivery of a product, different economic properties of the product are defined. Then the two stages are analysed from the perspective of investment and consumption respectively, and the competition criterion of inclusivity distribution and the reasons for exclusion are deduced. According to the causes of different problems in the two stages, the research direction of inclusive solutions is pointed out, and the economical sustainability of inclusive design is analysed. This paper emphasizes that the goal of inclusive design lies not only in the partial and temporary elimination of exclusion, but also in how to distribute the freedom of choice.
Late watergrass [Echinochloa phyllopogon (Stapf) Koso-Pol.] is one of the most persistent weeds in rice fields and shows resistance to some acetolactate synthase (ALS)-inhibiting herbicides, such as penoxsulam. Previous studies of E. phyllopogon’s herbicide resistance have focused on non–target site resistance mechanisms. In this study, E. phyllopogon populations from Heilong Jiang Province, China, that were possibly resistant to penoxsulam were used to identify the target site–based mechanisms of resistance. Population HSRH-520 showed a 25.4-fold higher resistance to penoxsulam than the sensitive population, HSRH-538. HSRH-520 was resistant to other ALS inhibitors, with resistance indexes ranging from 17.1 to 166. Target-gene sequence analysis revealed two different ALS genes in E. phyllopogon; a Pro-197-Ser substitution occurred in the ALS-2 gene of HSRH-520. In vitro activity assays revealed that the penoxsulam concentrations required to inhibit 50% of the ALS activity were 13.7 times higher in HSRH-520 than in HSRH-538. Molecular-docking tests showed that the Pro-197-Ser mutation reduced the binding affinity between ALS and ALS inhibitors belonging to the triazolopyrimidine, sulfonylaminocarbonyltriazolinone, and sulfonylurea families, and there were almost no effects on binding affinity when the ALS inhibitors were of the pyrimidinylthiobenzoate and imidazolinone families. Overall, the results indicated and verified that the Pro-197-Ser mutation leads to increased ALS activity by reducing the binding affinity of the inhibitor and ALS. This is the first report on the Pro-197-Ser mutation in the complete ALS gene of E. phyllopogon and will aid future research of target site–based resistance mechanisms of E. phyllopogon to ALS inhibitors.
Novel NiMoO4-integrated electrode materials were successfully prepared by solvothermal method using Na2MoO4·2H2O and NiSO4·6H2O as main raw materials, water, and ethanol as solvents. The morphology, phase, and structure of the as-prepared materials were characterized by SEM, XRD, Raman, and FT-IR. The electrochemical properties of the materials in supercapacitors were investigated by cyclic voltammetry, constant current charge–discharge, and electrochemical impedance spectroscopy techniques. The effects of volume ratio of water to ethanol (W/E) in solvent on the properties of the product were studied. The results show that the pure phase monoclinic crystal NiMoO4 product can be obtained when the W/E is 2:1. The diameter and length are 0.1–0.3 µm and approximately 3 µm, respectively. As an active material for supercapacitor, the NiMoO4 nanorods material delivered a discharge specific capacitance of 672, 498, and 396 F/g at a current density of 4, 7, and 10 A/g, respectively. The discharge specific capacitance slightly decreased from 815 to 588 F/g with a retention of 72% after 1000 cycles at a current density of 1 A/g. With these superior capacitance properties, the novel NiMoO4 integrated electrode materials could be considered as promising material for supercapacitors.
Toxigenic Clostridium difficile (C. difficile) carriers represent an important source in the transmission of C. difficile infection (CDI) during hospitalisation, but its prevalence and mode in patients with hepatic cirrhosis are not well established. We investigated longitudinal changes in carriage rates and strain types of toxigenic C. difficile from admission to discharge among hepatic cirrhosis patients. Toxigenic C. difficile was detected in 104 (19.8%) of 526 hepatic cirrhosis patients on admission, and the carriage status changed in a portion of patients during hospitalisation. Approximately 56% (58/104) of patients lost the colonisation during their hospital stay. Among the remaining 48 patients who remained positive for toxigenic C. difficile, the numbers of patients who were positive at one, two, three and four isolations were 10 (55.6%), three (16.7%), two (11.1%) and three (16.7%), respectively. Twenty-eight patients retained a particular monophyletic strain at multiple isolations. The genotype most frequently identified was the same as that frequently identified in symptomatic CDI patients. A total of 25% (26/104) of patients were diagnosed with CDI during their hospital stay. Conclusions: Colonisation with toxigenic C. difficile strains occurs frequently in cirrhosis patients and is a risk factor for CDI.
Barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] is acknowledged to be the most troublesome weed in rice fields in Anhui and Jiangsu provinces of China. It cannot be effectively controlled using certain acetolactate synthase (ALS)-inhibiting herbicides, including penoxsulam. Echinochloa crus-galli samples with suspected resistance to penoxsulam were collected to identify the target site–based mechanism underlying this resistance. Populations AXXZ-2 and JNRG-2 showed 33- and 7.3-fold resistance to penoxsulam, respectively, compared with the susceptible JLGY-3 population. Cross-resistance to other ALS inhibitors was reported in AXXZ-2 but not in JNRG-2, and occasionally showed higher sensitivity than JLGY-3. In vitro ALS activity assays revealed that penoxsulam concentrations required to inhibit 50% of ALS activity were 11 and 5.2 times greater in AXXZ-2 and JNRG-2, respectively, than in JLGY-3. DNA and predicted amino acid sequence analyses of ALS revealed Ala-205-Val and Ala-122-Gly substitutions in AXXZ-2 and JNRG-2, respectively. Our results indicate that these substitutions in ALS are at least partially responsible for resistance to penoxsulam.
Although the streaked optical pyrometer (SOP) system has been widely adopted in shock temperature measurements, its reliability has always been of concern. Here, two calibrated Planckian radiators with different color temperatures were used to calibrate and verify the SOP system by comparing the two calibration standards using both multi-channel and single-channel methods. A high-color-temperature standard lamp and a multi-channel filter were specifically designed for the measurement system. To verify the reliability of the SOP system, the relative deviation between the measured data and the standard value of less than 5% was calibrated out, which demonstrates the reliability of the SOP system. Furthermore, a method to analyze the uncertainty and sensitivity of the SOP system is proposed. A series of laser-induced shock experiments were conducted at the ‘Shenguang-II’ laser facility to verify the reliability of the SOP system for temperature measurements at tens of thousands of kelvin. The measured temperature of the quartz in our experiments agreed fairly well with previous works, which serves as evidence for the reliability of the SOP system.
Fatigue properties of Mo/W multilayers with individual layer thickness (λ) of 5, 20, 50 and 100 nm on flexible polyimide substrates were investigated. The experimental results show that the fatigue resistance increases with decreasing λ from 100 nm to 20 nm, and reaches the maximum at λ=20 nm, and then decreases when further decreasing λ. Fatigue cracks of Mo/W multilayers with different λ were found to propagate along columnar grain boundary in the out-of-plane direction and along the boundary of cluster structures. The enhanced fatigue resistance is attributed to the larger cluster inclination angles and the more tortuous in-plane cracking paths.
Graphitic carbon nitride (g-C3N4) microspheres (CNMS) were fabricated via a solvothermal method by using dicyandiamide and cyanuric chloride as precursors. The morphology, band structure, and defects can be simultaneously regulated by merely adjusting the concentration of precursors. Structural characterization results indicate that all the prepared samples possess spherical morphology, while the band gap decreased as the precursor concentration increased from 8 mmol (CNMS-1) to 24 mmol (CNMS-3). Besides, ultraviolet photoelectron spectroscopy results suggested that the valence band of CNMS-2 (16 mmol) was much higher than that of CNMS-1 and CNMS-3. Additionally, organic elemental analysis, X-ray photoelectron spectroscopy, and electron paramagnetic resonance results unveil the formation of nitrogen defects on the surface of prepared samples. Besides, CNMS-2 exhibits an enhanced apparent reaction rate constant of RhB degradation than that of CNMS-1 and CNMS-3. The improved apparent reaction rate constant may be due to the lowered valence band as well as the formation of nitrogen defects. This work might guide the regulation of the morphology and band structure of g-C3N4-based materials prepared via the one-pot hydrothermal method.
Two phases of diabase-sill-forming magmatism are recorded within the Badu anticline where magmas were emplaced into upper Palaeozoic carbonates and clastic rocks of the Youjiang fold-and-thrust belt in the SW South China Block, China. Zircons from these diabase units yield weighted mean U–Pb ages of 249.2±2.0 Ma and 187.1±3.3 Ma, and magmatic oxygen fugacity values from ‒20 to ‒6 (average of ‒12, equating to FMQ +5) and ‒20 to ‒10 (average of ‒15, equating to FMQ +2), respectively. These data indicate that the sills were emplaced during Early Triassic and Early Jurassic times. The discovery of c. 250 Ma mafic magmatism in this area was probably related to post-flood-basalt extension associated with the Emeishan mantle plume or rollback of the subducting Palaeo-Tethys slab. The c. 190 Ma diabase sills indicate that the southwestern South China Block records Early Jurassic mafic magmatism and lithospheric extension that was likely associated with a transition from post-collisional to within-plate tectonic regimes. The emplacement of diabase intrusions at depth may have driven hydrothermal systems, enabling the mobilization of elements from sedimentary rocks and causing the formation of a giant epigenetic metallogenic domain. The results indicate that high-oxygen-fugacity materials within basement rocks caused crustal contamination of the magmas, contributing to the wide range of oxygen fugacity conditions recorded by the Au-bearing Badu diabase. In addition, data from inherited xenocrystic zircons within the Badu diabase and detrital zircons from basement rocks suggest that the Neoproterozoic Jiangshao suture extends to the south of the Badu anticline.
Inkjet technology is a commendable tool in many applications including graphics printing, bioengineering and micro-electromechanical systems (MEMS). Droplet stability is a key factor influencing inkjet performance. The stability can be analysed using dimensionless numbers that usually combine thermophysical properties and system dimensions. In this paper, a drop-on-demand (DOD) inkjet experimental system is established. A numerical model is developed to investigate the influence of the operating conditions on droplet stability, including nozzle dimensions, driving parameters (the pulse amplitude and width used to drive droplet formation) and fluid properties. The results indicate that the stability can be improved by decreasing the pulse amplitude and width, decreasing the fluid density and viscosity or increasing the nozzle diameter and fluid surface tension. Based on case analysis and modelling, a dimensionless number (
), the reciprocal of the Ohnesorge number, is numerically determined for a stable droplet to lie in a range between 4 and 8. To explicitly combine the driving parameters, a new stability criterion,
, is further proposed. A general rule taking into account both
is proposed for choosing appropriate driving parameters to eject stable droplets for a known nozzle and fluid, which is further validated by experiments.
A facile synthesis procedure of nitrogen-self-doped porous carbon (NPC) derived from abundant natural biological materials has been presented. The pyrolysis temperature and the weight ratio of Co3O4 to carbon play a key role in determining microscopic structure and electrochemical performances of the final materials. The ordered mesostructures with nanopores in the channel walls provided support for immobilization of well-dispersed Co3O4 nanoparticles. They also served as a highly conductive substrate for effectively alleviating severe particle aggregation during the charge/discharge processes, which prevented capacity fading from deteriorated electric contact between the components. Taking advantage of the interconnected porous structures and high specific surface area (1799 m2/g) of carbon substrate, the Co3O4/NPC composite as anode in lithium-ion battery delivers a stable reversible capacity of 903 mA h/g after 400 cycles. It is expected that by loading other electrode active materials on such carbon material, the manufacture of the promising anode materials with excellent cycle stability is highly possible.
An epigenetic mechanism has been suggested to explain the effects of the maternal diet on the development of disease in offspring. The present study aimed to observe the effects of a maternal high-lipid, high-energy (HLE) diet on the DNA methylation pattern of male offspring in mice. Female C57BL/6J mice were fed an HLE diet during gestation and lactation. The genomic DNA methylations at promoter sites of genes in the liver, mRNA and protein levels of selected genes related to lipid and glucose metabolism were measured by microarray, real-time PCR and Western blot. The results indicated that the percentage of methylated DNA in offspring from dams that were fed an HLE diet was significantly higher than that from dams that were fed a chow diet, and most of these genes were hypermethylated in promoter regions. The nuclear protein content and mRNA levels of hypermethylated genes, such as PPARγ and liver X receptor α (LXRα), were decreased significantly in offspring in the HLE group. The results suggested that the DNA methylation profile in adult offspring livers was changed by the maternal HLE diet during gestation and lactation.
It has not been established which specific measures of obesity might be most appropriate for predicting CVD risk in Asians. The objectives of the present study were to determine the associations of BMI, waist circumference (WC) and waist:height ratio (WHtR) with CVD risk factors and to evaluate the optimal cut-off values to define overweight or obesity in Chinese adults. Data collected from seven nationwide health examination centres during 2008 and 2009 were analysed. The BMI, WC and WHtR of 244 266 Chinese adults aged ≥ 20 years included in the study were measured. Logistic regression models were fit to evaluate the OR of each CVD risk factor according to various anthropometric indices. Receiver operating characteristic (ROC) analyses were conducted to assess the optimal cut-off values to predict the risk of diabetes, hypertension, dyslipidaemia and the metabolic syndrome. WHtR had the largest areas under the ROC curve for all CVD risk factors in both sexes, followed by WC and BMI. The optimal cut-off values were approximately 24·0 and 23·0 kg/m2 for BMI, 85·0 and 75·0 cm for WC, and 0·50 and 0·48 for WHtR for men and women, respectively. According to well-established cut-off values, BMI was found to be a more sensitive indicator of hypertension in both men and women, while WC and WHtR were found to be better indicators of diabetes and dyslipidaemia. A combination of BMI and central obesity measures was found to be associated with greater OR of CVD risk factors than either of them alone in both sexes. The present study demonstrated that WHtR and WC may be better indicators of CVD risk factors for Chinese people than BMI.
This paper studies the influence of inert gas additions He, Ar, Kr and Xe on breakdown voltage within dielectric barrier discharge reactor with oxygen feed gas. The density-normalized effective ionization coefficients αeff/N are calculated for inert gas/O2 mixtures, the critical reduced field E/Ncr is obtained where the electron ionization exactly balances the attachment. Adding inert gases would lead to the decreasing critical reduced field strength E/Ncr due to the enhancement of effective ionization coefficient. In addition, inert gas additions have shown to reduce the breakdown voltage. Moreover the numerical breakdown voltage values and the experimental data are plotted for the sake of comparison and results show that calculated results are in agreement with the experimental values. Parametric study offers substantial insight in plasma physics, as well as in ozone generation applications.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.