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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.
High-entropy ceramic (HEC) films refer to the carbide, boride, oxide, or nitride films of the high-entropy alloy, which have potential applications under high temperatures. In this study, we fabricated the HEC NbTiAlSiZrNx films using magnetron sputtering under various deposition atmospheres. The phase structure evolution and the mechanical properties of three HEC films under high temperatures were investigated. The HEC films demonstrated good thermal stability as well as high hardness. After annealing for 24 h at 700 °C, the films remained in an amorphous phase without obvious crystallization, and the hardness of the films declined. Nanocrystallizations occurred in films deposited at a nitrogen flow rate of 4 sccm and 8 sccm after annealing for 30 min at 900 °C and exhibited an face-centered cubic structure. HEC NbTiAlSiZrNx films have potential applications as protective coatings under high temperatures.
To assess the association of fish consumption with risk of dementia and its dose–response relationship, and investigate variations in the association among low-, middle- and high-income countries.
A new community-based cross-sectional study and a systematic literature review.
Urban and rural communities in China; population-based studies systematically searched from worldwide literature.
Chinese adults aged ≥60 years in six provinces (n 6981) took part in a household health survey of dementia prevalence and risk factors. In addition, 33 964 participants from eleven published and eligible studies were included in the systematic review and meta-analysis.
In the new study in China, 326 participants were diagnosed with dementia (4·7 %); those who consumed any amount of fish in the past two years v. those who consumed no fish had reduced risk of dementia (adjusted OR=0·73, 95 % CI 0·64, 0·99), but the dose–response relationship was not statistically significant. The meta-analysis of available data from the literature and the new study showed relative risk (RR) of dementia of 0·80 (95 % CI 0·74, 0·87) for people with fish consumption; the impact was similar among countries with different levels of income. Pooled dose–response data revealed RR (95 % CI) of 0·84 (0·72, 0·98), 0·78 (0·68, 0·90) and 0·77 (0·61, 0·98) in people with low, middle and high consumption of fish, respectively. Corresponding figures for Alzheimer’s disease were 0·88 (0·74, 1·04), 0·79 (0·65, 0·96) and 0·67 (0·58, 0·78), respectively.
Greater consumption of fish is associated with a lower risk of dementia. Increasing fish consumption may help prevent dementia worldwide regardless of income level.
A previous study showed that flesh quality of large yellow croaker (LYC) was improved by feeding dietary hydroxyproline (Hyp, 0·69 %). The aim of the present study was to explore the underlying mechanisms using transcriptomics and metabolomics analysis. The metabolomics analysis showed that muscle metabolite profiles could be clearly separated between the basal diet and Hyp supplementation diet. Metabolites including betaine, Hyp, lactate, glucose-6-phosphate, trimethylamine N-oxide, taurine, creatine, inosine monophosphate, histamine and serine made significant contribution to the separation. Compared with the control diet, the transcriptomics analysis identified a total of 334 different expressed genes, of which 298 genes were up-regulated and thirty-six genes were down-regulated in the Hyp supplementation group. The altered genes of the Hyp supplementation group were involved in collagen metabolism, lipid metabolism and energy metabolism. The integrated results revealed that the increased muscle collagen content in the Hyp supplementation diet was partly because of its enhancement of biosynthesis and the reduction of degradation. The improvement of muscle quality by dietary Hyp supplementation could also be related to a good utilisation of glucose through enhancement of glycolysis. It was concluded that dietary Hyp supplementation could improve flesh quality because of comprehensive metabolism changes including elevated collagen content, glycolysis, lipid metabolism and flesh flavour of LYC. The present study provided a novel strategy to understand the underlying molecular mechanism of flesh quality of LYC fed diet with Hyp supplementation.
In this systematic review and meta-analysis of observational studies, we aimed to estimate the associations between prenatal vitamin D status and offspring growth, adiposity and metabolic health. We searched the literature in human studies on prenatal vitamin D status and offspring growth in PubMed, up to July 2017. Studies were selected according to their methodological quality and outcomes of interest (anthropometry, fat mass and diabetes in offspring). The inverse variance method was used to calculate the pooled mean difference (MD) with 95 % CI for continuous outcomes, and the Mantel–Haenszel method was used to calculate the pooled OR with 95 % CI for dichotomous outcomes. In all, thirty observational studies involving 35 032 mother–offspring pairs were included. Vitamin D status was evaluated by circulating 25-hydroxyvitamin D (25(OH)D) level. Low vitamin D status was based on each study’s cut-off for low 25(OH)D levels. Low prenatal vitamin D levels were associated with lower birth weight (g) (MD −100·69; 95 % CI −162·25, −39·13), increased risk of small-for-gestational-age (OR 1·55; 95 % CI 1·16, 2·07) and an elevated weight (g) in infant at the age of 9 months (g) (MD 119·75; 95 % CI 32·97, 206·52). No associations were observed between prenatal vitamin D status and other growth parameters at birth, age 1 year, 4–6 years or 9 years, nor with diabetes type 1. Prenatal vitamin D may play a role in infant adiposity and accelerated postnatal growth. The effects of prenatal vitamin D on long-term metabolic health outcomes in children warrant future studies.
In this paper, we introduce a lower extremity exoskeleton CUHK-EXO that is developed to help paraplegic patients, who have lost the motor and sensory functions of their lower limbs to perform basic daily life motions. Since the sit-to-stand and stand-to-sit (STS) motion is the first step for paraplegic patients toward walking, analysis of the exoskeleton's applicability to the STS motion assistance is performed. First, the human-exoskeleton system (HES) is modeled as a five-link model during the STS motion, and the center of pressure (COP) on the ground and center of gravity of the whole system are calculated. Then, a description of the CUHK-EXO hardware design is presented, including the mechatronics design and actuator selection. The COP position is an important factor indicating system balance and wearer's comfort. Based on the COP position, a trajectory online modification algorithm (TOMA) is proposed for CUHK-EXO to counteract disturbances, stabilize system balance, and improve the wearer's comfort in the STS motion. The results of STS motion tests conducted with a paraplegic patient demonstrate that CUHK-EXO can provide a normal reference pattern and proper assistive torque to support the patient's STS motion. In addition, a pilot study is conducted with a healthy subject to verify the effectiveness of the proposed TOMA under external disturbances before future clinical trials. The testing results verify that CUHK-EXO can counteract disturbances, and help the wearer perform the STS motion safely and comfortably.
The continental regions of China are extensively covered by snow during winter. In this paper, the seasonal snow cover in the Tien Shan and Altay mountains is observed and analyzed, based on the characteristics of the dry-cold snow cover accumulating under the continental climatic conditions in northwest China. Compared with the humid-warm snow cover, the dry-cold snow cover is characterized mainly by small density, low water content, large temperature gradient, thick depth hoar, etc., and its metamorphism is dominated by the thermal exchange and the pressure of the overlying snow layers. According to the observed data, the solar radiation flux on the snow surface is dominated by a negative balance in the arid areas in China during the snow season; the albedo on the new-fallen-snow surface is up to 96%, and the transmission depth of shortwave radiation in dry-cold snow cover is 28 cm. During the snowmelt season in spring, the thickness of the depth hoar can occupy 80% of the whole snow cover.
Toxoplasmosis is a serious zoonoses disease and opportunistic, and can be life-threatening. Dexamethasone (DEX) is widely used in the clinic for treatment of inflammatory and autoimmune diseases. However, long-term use of DEX is often easy to lead to acute toxoplasmosis in patients, and the potential molecular mechanism is still not very clear. The aims of this study were to investigate the effect of DEX on proliferation of Toxoplasma and its molecular mechanisms, and to establish the corresponding control measures. All the results showed that dexamethasone could enhance the proliferation of Toxoplasma gondii tachyzoites. After 72 h of DEX treatment, 566 (±7) tachyzoites were found in 100 host cells, while only 86 (±8) tachyzoites were counted from the non-treated control cells (P < 0·01). Gas chromatography (GC) analysis showed changes in level and composition of fatty acids in DEX-treated host cells, and T. gondii. Fish oil was added as a modulator of lipid metabolism in experimental mice. It was found that mice fed with fish oil did not develop the disease after infection with T. gondii, and the structure of fatty acids in plasma changed significantly. The metabolism of fatty acid in the parasites was limited, and the desaturase gene expression was downregulated. These results indicate that the molecular mechanism of dexamethasone to promote the proliferation of T. gondii may be that dexamethasone induces the change of fatty acids composition of tachyzoites and host cells. Therefore, we recommend supplementation of fatty acid in immunosuppressive and immunocompromised patients in order to inhibit toxoplasmosis.
Spark plasma sintering (SPS) is adopted to fabricate transparent AlON ceramics at 1350–1500 °C under 40 MPa, using a bimodal γ-AlON powder synthesized by the carbothermal reduction and nitridation method. After holding 10 min, high density samples are obtained, and their optical transmittance is investigated over the wavelength range of 1330–6000 nm. Despite the samples SPS-processed at 1350 °C indicate the presence of three-phases: γ-AlON, α-Al2O3, and h-AlN, they show high infrared transparency, i.e., the maximum transmittance for 1.2 mm thick specimens is up to 77.3% at ∼3900 nm. Also, the processed samples exhibit high hardness of 17.81 GPa. The high infrared transmittance should be mainly attributed to high density and rationally controlled grain size distribution, and the high hardness is apparently caused by a small grain size.
The discovery of the ancient city of Loulan in Xinjiang, China, at the beginning of the 20th century was of great significance for understanding the evolution of culture and civilization in Inner Asia. However, due to the lack of systematic chronological studies, the history of this ancient city remains unclear, particularly the date of its construction and abandonment. Here, we present the results of the first systematic radiocarbon (14C) dating carried out on artifacts from ancient Loulan. Our results show that human activity began as early as 350 cal BC, flourished during the interval from the 1st to 4th centuries AD, and completely disappeared around 600 AD. Most of the buildings in the city were constructed during the Eastern Han Dynasty rather than in Wei/Jin Dynasty, as previously indicated by excavated documents and letters (Hedin 1898; Xiao 2006). The development and flourishing of Loulan coincided with the interval of high ice accumulation and meltwater supply from surrounding mountains. The city began to decline and was finally abandoned following an abrupt decrease in ice accumulation and meltwater supply (Yao et al. 1996; Lauterbach et al. 2014), suggesting that natural climate change was the major factor responsible for the abandonment of Loulan.
Previous studies have thoroughly investigated the prevalence and risk factors for completed suicide. In marked contrast is the lack of a better understanding of attempted suicide in the elderly. The aim of this study was to estimate the prevalence of attempted suicide in the elderly and examine the associated factors.
Using a multi-stage cluster sampling approach, a cross-sectional survey of 8,399 elderly house-dwelling residents was conducted in Shanghai, China.
The two-week prevalence of attempted suicide in the elderly was 0.75%. In the bivariate analysis, having no caregivers, depressive, anxiety, sad, fear, obsessive-compulsive and anger symptom, and lower scores on the Barthel Index of Activities of Daily Living and the Lawton Instrumental Activities of Daily Living Scale were significantly associated with an increased risk of attempted suicide in the elderly. In the multivariate analysis, sad and fear symptoms were significantly and independently associated with a higher risk of attempted suicide in the elderly.
The two-week prevalence of attempted suicide in the elderly is relatively high when compared with the annualized or lifetime prevalence reported in China and foreign settings. Elderly individuals with certain mental symptoms should be targeted for suicide prevention and provided with timely mental health support.
Gauged river flow records from China generally span only a few decades, which hampers the detection of long-term, decadal- to centennial-scale cycles and trends in streamflow variability. New and updated tree-ring chronologies help reconstructed the water-year (October–September) streamflow for the Aksu River, which is an important river at the edge of the Taklimakan Desert that drains into the Tarim Basin. The reconstruction dates back to 1692 and has an adjusted r2 of 0.61 (1957–2006). Based on frequency, intensity and duration of droughts and pluvial events, the lowest streamflows occurred in the 1920s. Since then streamflow has continuously increased, and was exceptionally rapidly after the 1960s, until today. The start and end of the 20th century to the present were the highest streamflow periods. The mid-20th century was the longest and driest period over the past 300 yr. The reconstructed streamflow series has a strong positive correlation with the North Atlantic Oscillation Index. Changes in mid-latitude circulation patterns influencing precipitation may have indirectly resulted in streamflow variations along the Aksu River over the past 300 yr. The rapid increase and the exceptional streamflows of the 1960s are likely linked with global warming and mid-latitude atmospheric circulation changes.
The microstructure evolution of a typical nickel-based superalloy was studied in the temperature range of 960–1160 °C with the strain rate of 0.001 s−1 by using electron backscattered diffraction technique. Based on the grain orientation spread method, the dynamic recrystallization (DRX) grains were distinguished from the deformed grains. The results revealed that the volume fraction and the size of DRX grains increased with the increasing deformation temperatures. Most of the original Σ3 boundaries lost their twin characteristics due to crystal rotations during hot deformation. Meanwhile, lots of new Σ3 boundaries were formed in the DRX grains mainly by growth accidents. Moreover, the deformation temperature had a similar effect on the fraction of Σ3 boundary and the Σ3 boundary density in the DRX domains, which increased firstly and then decreased with the increasing deformation temperature. The Σ3 boundary density was analyzed as a function of grain size, and the critical grain size below which no twin forms was calculated to be 2.06 µm. In addition, the coherent Σ3 boundaries were easier to form at the higher deformation temperature due to their lower boundary energy.
Most long QT syndrome patients are associated with genetic mutations. We aimed to investigate the clinical and biochemical characteristics and look for genotype-based preventive implications in Chinese long QT syndrome patients.
Methods and results
We identified two missense mutations of the KCNQ1 gene in two independent Chinese families, including a previously reported mutation R380S in the C-terminus and a novel mutation W305L in the P-loop domain of the Kv7.1 channel, respectively. The proband with R380S was an 11-year-old girl who suffered a prolonged corrected QT interval of 660 ms, recurrent syncope, and sudden cardiac death, whose father was an asymptomatic carrier. The mutation W305L was detected in a 36-year-old woman with long QT syndrome and her immediate family members including the proband’s younger sister with an unexplained syncope, her son, and her elder daughter without symptoms. Metoprolol appeared to be effective in preventing arrhythmias and syncope in long QT syndrome patients with mutation W305L. Both R380S and W305L mutations led to “loss-of-function” of the Kv7.1 channel accounting for the clinical phenotypes.
We first show two missense KCNQ1 mutations – R380S and W305L – in Chinese long QT syndrome patients, resulting in the loss of protein function. Mutation W305L in the P-loop domain of the Kv7.1 may derive a pronounced benefit from β-blocker therapy in symptomatic long QT syndrome patients, whereas mutation R380S located in the C-terminus may be associated with a high risk of sudden cardiac death.
Novel composite materials with wide pores were synthesized by an in situ technique using kaolin, palygorskite and pseudoboehmite as raw materials. The characterization results indicated that the synthesis components and conditions influenced the micro-, meso- and macro-porosity of the composite materials. The composites contained 53.5% zeolite Y and had much larger specific surface areas and pore volumes as well as significant hydrothermal stability. Fluid catalytic cracking (FCC) catalysts were prepared based on the composite materials. The results indicated that the as-prepared catalysts possessed a unique pore structure which assisted in diffusion-controlled reactions. In addition, the attrition resistance, activity and hydrothermal stability of the catalyst studied were superior to those of a reference catalyst. The catalyst studied also exhibited excellent nickel and vanadium passivation performance, strong ‘bottoms upgrading’ selectivity and better gasoline and coke selectivity.
Thermal stress can induce birefringence in a laser medium, which can cause depolarization of the laser. The depolarization effect will be very severe in a high-average-power laser. Because the depolarization will make the frequency doubling efficiency decline, it should be compensated. In this paper, the thermal characteristics of two kinds of materials are analyzed in respect of temperature, thermal deformation and thermal stress. The depolarization result from thermal stress was simulated. Depolarization on non-uniform pumping was also simulated, and the compensation method is discussed.
August–July precipitation has been reconstructed back to AD 1724 for the Mohe region in the northern Greater Higgnan Mountains, China, using Pinus sylvestris var. mongolica tree-ring width. The reconstruction explains 39% of the variance in the precipitation observed from AD 1960–2008. Some droughts noted in historical documents are precisely captured in our reconstruction. Wet periods occurred during the periods of AD 1734–1785, AD 1805–1830, AD 1863–1880, AD 1922–1961, and AD 1983–1998; while the periods of AD 1786–1804, AD 1831–1862, AD 1881–1921, and AD 1962–1982 were relatively dry. Power spectral and wavelet analyses demonstrated the existence of significant 24-yr, 12-yr, and 2-yr cycles of variability. The results of the spatial correlations suggest that our reconstruction contains climatic signals for the southern Stanovoy Range and the northern Greater Higgnan Mountains. The positive correlations between the new reconstructed precipitation series and two precipitation reconstructions indicate that our precipitation reconstruction captures broad-scale regional climatic variations. A comparison between the weakening tendency of summer monsoon and the dry period of our reconstruction reveals that the annual precipitation in the Mohe region is partly influenced by the East Asian Summer Monsoon.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.