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A disruption database characterizing the current quench of disruptions with ITER-like tungsten divertor has been developed on EAST. It provides a large number of plasma parameters describing the predisruptive plasma, current quench time, eddy current, and mitigation by massive impurity injection, which shows that the current quench time strongly depends on magnetic energy and post-disruption electron temperature. Further, the energy balance and magnetic energy dissipation during the current quench phase has been well analysed. Magnetic energy is also demonstrated to be dissipated mainly by ohmic reheating and inductive coupling, and both of the two channels have great effects on current quench time. Also, massive gas injection is an efficient method to speed up the current quench and increase the fraction of impurity radiation.
Preoperative nutritional status plays an important role in predicting postoperative outcomes. Prognostic Nutritional Index (PNI) and Controlling Nutritional Status (CONUT) are good tools to assess patients’ nutritional status. They have been used in predicting outcomes in various malignancies, but few studies have focused on pancreatic adenocarcinoma (PDAC) patients. Totally, 306 PDAC patients were enrolled. The propensity score matching (PSM) method was introduced to eliminate the baseline inequivalence. Patients with different PNI (or CONUT) scores showed inequivalence baseline characteristics, and patients with compromised nutritional status were related with a more advanced tumour stage. After PSM, the baseline characteristics were well balanced. Both low PNI (≤45) and high CONUT (≥3) were independent risk factors for poor overall survival (P < 0·05), and the result remained the same after PSM. Survival analysis demonstrated both patients with low PNI and high CONUT score were associated with poorer survival, and the result remained the same after PSM. The results of AUC indicated that CONUT might have a higher sensitivity and specificity in predicting complications and survival. Preoperative low PNI (≤45) and high CONUT (≥3) scores might be reliable predictors of prognosis and surgical complications in PDAC patients. Compared with PNI, CONUT might be more effective.
Human milk fat is specially tailored to supply the developing infant with adequate and balanced nutrients. The present study aimed to quantify the composition of fatty acids, tocopherols and carotenoids in human milk, with special emphasis on the lactational changes. Colostrum, transitional and mature milk samples were collected longitudinally from the same forty-two healthy, well-nourished Chinese mothers. Fatty acids were quantified by GC with carotenoids (carotenes and xanthophylls) and tocopherols (α-, γ-tocopherol) determined by HPLC. Total fatty acid (TFA) content increased from 15·09 g/l in colostrum to 32·57 g/l in mature milk with the percentages of DHA and arachidonic acid (ARA) decreased. The ratio of n-6:n-3 PUFA and ARA:DHA remained constant during lactation at about 11:1 and 1·3:1, respectively. Both α-tocopherol and γ-tocopherol decreased over lactation with the ratio of α-:γ-tocopherol declined significantly from 7·21:1 to 4·21:1 (P < 0·001). Carotenoids all dropped from colostrum to mature milk as the less polar carotenes dropped by 88·67 %, while xanthophylls only dropped by 35·92 %. Lutein was predominated in both transitional and mature milk carotenoids (51·64–52·49 %), while colostrum carotenoids were mainly composed of lycopene (32·83 %) and β-carotene (30·78 %). The concentrations of tocopherols and xanthophylls but not carotenes were positively associated with TFA content in milk. These results suggested that colostrum and mature milk contained divergent lipid profiles and selective transfer mechanisms related to polarity might be involved. The present outcomes provide new insights for future breast-feeding studies, which also add in scientific evidences for the design of both initial and follow-on infant formulas.
The factors associated with suicidal ideation among adolescents have been extensively characterised, but the mechanisms underlying the complexities of the relationship between experiences of childhood trauma and suicidal ideation have been less studied. This study examined the direct effect of childhood trauma on suicidal ideation on the one hand and whether school bullying victimisation and Internet addiction mediate the association between childhood trauma and suicidal ideation on the other hand.
This school-based mental health survey was carried out in Qinghai Province in Northwest China in December 2019. We employed standardised questionnaires to collect sociodemographic and target mental health outcomes. Hierarchical multiple logistic regression and structural equation modelling were performed for the data analyses.
This study included 5864 university students. The prevalence of lifetime suicidal ideation and Internet addiction were 34.7% and 21.4%, respectively. Overall, 16.4% and 11.4% of participants reported experiences of childhood trauma and school bullying victimisation, respectively. There were direct effects of childhood trauma, school bullying victimisation and Internet addiction on suicidal ideation. The total effect of childhood trauma on suicidal ideation was 0.201 (p < 0.001). School bullying victimisation and Internet addiction mediated the relationship between childhood trauma and suicidal ideation. Internet addiction played a mediating role between school bullying and suicidal ideation.
Childhood trauma had both direct and indirect effects on suicidal ideation; these effects were mediated by school bullying victimisation and Internet addiction in Chinese university students. Elucidating these relationships will therefore be useful in developing and implementing more targeted interventions and strategies to improve the mental well-being of Chinese university students.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
The transition metal compound catalysts have been taken a great part in renewable energy conversion and storage systems. Herein, we report the uniform CoFe2O4 nanoparticles with abundant oxygen vacancies and specific active surface exposed through the simple hydrothermal reaction for improving the electrocatalytic performance and stability. They show good electrocatalytic performance for hydrogen evolution reaction in 0.5 M H2SO4 with an onset potential of 20 mV, the overpotential of 45 mV (at j = 10 mA/cm2), and remarkable long-term stability more than 100 h at different current densities and better oxygen reduction reaction activity with lower overpotential in 0.1 M KOH. Moreover, the home-made primary Zn–air batteries, using CoFe2O4 nanoparticles as an air–cathode display the high open-circuit voltage of 1.47 V and the maximum power density of 142 mW/cm2. The two-series-connected batteries fabricated by CoFe2O4 nanoparticles can support a light-emitting diode to work for more than 48 h.
We propose a hybrid spectral element method for fractional two-point boundary value problem (FBVPs) involving both Caputo and Riemann-Liouville (RL) fractional derivatives. We first formulate these FBVPs as a second kind Volterra integral equation (VIEs) with weakly singular kernel, following a similar procedure in . We then design a hybrid spectral element method with generalized Jacobi functions and Legendre polynomials as basis functions. The use of generalized Jacobi functions allow us to deal with the usual singularity of solutions at t = 0. We establish the existence and uniqueness of the numerical solution, and derive a hptype error estimates under L2(I)-norm for the transformed VIEs. Numerical results are provided to show the effectiveness of the proposed methods.
Why do authoritarian regimes try to improve the quality of their governance? In the absence of democratic institutions to monitor, reward and punish their performance, authoritarian politicians are normally expected to seek their self-interest through corruption and rewards to cronies, rather than providing for the public welfare. However, the Chinese state has actively promoted improved governance in recent years, with greater attention to quality of life issues to balance the primary focus on sustaining rapid economic growth. This paper analyses intra-national variation in the provision of public goods in urban China and the impact of public goods on regime support. Does better governance lead to higher levels of public support for the regime, even in the absence of democratic elections? Our evidence suggests that it does, with a greater impact for the local level than for the centre.
Current evidence of the relationship between diets and Fe status is mostly derived from studies in developed countries with Western diets, which may not be translatable to Chinese with a predominantly plant-based diet. We extracted data that were nationally sampled from the 2009 wave of China Health and Nutrition Survey; dietary information was collected using 24-h recalls combined with a food inventory for 3 consecutive days. Blood samples were collected to quantify Fe status, and log-ferritin, transferrin receptor and Hb were used as Fe status indicators. In total, 2905 (1360 males and 1545 females) adults aged 18–50 years were included for multiple linear regression and stratified analyses. The rates of Fe deficiency and Fe-deficiency anaemia were 1·6 and 0·7 % for males and 28·4 and 10·7 % for females, respectively. As red meat and haem Fe consumption differed about fifteen to twenty times throughout the five groups, divided by quintiles of animal protein intake per 4·2 MJ/d, only Fe status as indicated by log-ferritin (P=0·019) and transferrin receptor (P=0·024) concentrations in males was shown to be higher as intakes of animal foods increased. Log-ferritin was positively associated with intakes of red meat (B=0·3 %, P=0·01) and haem Fe (B=12·3 %, P=0·010) in males and with intake of non-haem Fe in females (B=2·2 %, P=0·024). We conclude that diet has a very limited association with Fe status in Chinese adults consuming a traditional Chinese diet, and a predominantly plant-based diet may not be necessarily responsible for poor Fe status.
In this study, hematite nanoparticles (α-Fe2O3 NPs) were synthesized by hydrothermal method, with morphologies (e.g., nanorhombohedra, nanobars, and nanospheres) facilely tuned by changing the concentrations of glycol in the hydrothermal solution. Then a low-cost and scalable electrophoretic deposition method was used to fabricate nanostructured α-Fe2O3 films as photoanodes for solar hydrogen generation. It was found that the film of α-Fe2O3 nanobars showed the highest photoelectrochemical (PEC) performance compared to those films of α-Fe2O3 nanorhombohedra and nanospheres, with photocurrent density reaching 0.7 mA/cm2 at 0.6 V versus Ag/AgCl. This PEC improvement may be related to the smaller diameters of nanobars shortening the carrier migration distance, reducing the recombination rate of photo-generated carriers. Moreover, all the α-Fe2O3 films showed much higher PEC performances with surface modified by Sn4+, mainly due to the reduced surface charge recombination, as the Sn4+ doped overlayer passivated surface defects. For the film of α-Fe2O3 nanobars, the photocurrent density was increased by 100%, reaching 1.4 mA/cm2 at 0.6 V versus Ag/AgCl.
The Qiangtang Metamorphic Belt (QMB) was considered to have either formed in situ by amalgmation of the North and South Qiangtang blocks or been underthrust from the Jinsha suture and exhumed in the interior of a single ‘Qiangtang Block’. A new Sphaeroschwagerina fusuline fauna discovered in the Raggyorcaka Lake area supports the interpretation that the North and South Qiangtang blocks were separated by a wide ocean during Asselian (Early Permian) time, indicating that the QMB was formed by the suturing of the Palaeotethys Ocean along the Longmu Co-Shuanghu suture.
The influence of environmental factors on germination and emergence of aryloxyphenoxy propanoate herbicide-resistant (AR) and -susceptible (AS) Asia Minor bluegrass were studied in laboratory and greenhouse experiments. Seeds were collected from AR and AS plants cultivated in separate greenhouses under the same environmental conditions. The results revealed that optimum temperatures for the germination of AS biotype were 10 to 25 C or alternating temperature of 15/5 to 30/20 C and light was not necessary. However, maximum germination occurred at 10 C or 15/5 C, and no germination occurred above 15 C or 25/15 C for the AR biotype. The AS Asia Minor bluegrass was consistently more tolerant to environmental stress, as evidenced by their greater germination at same pH value, osmotic potential, and NaCl concentration at 15/5 C compared to the AR biotype. Higher emergence rates were obtained when seeds were sown on the surface of soil for both biotypes. Emergence percentage of the AR biotype was below 14% when buried, whereas the AS biotype had 20% emergence at 2.5 cm burial depth. It is concluded that several environmental factors affect the germination of Asia Minor bluegrass, and the AS biotype showed higher germination percentage and a wider adaptive range under same treatments compared with the AR biotype. Due to the reduced emergence at depth, deep tillage could be an effective management to reduce AR Asia Minor bluegrass infestation in the following crop.
We consider in this paper numerical approximation of the linear Fluid-Structure Interaction (FSI). We construct a new class of pressure-correction schemes for the linear FSI problem with a fixed interface, and prove rigorously that they are unconditionally stable. These schemes are computationally very efficient, as they lead to, at each time step, a coupled linear elliptic system for the velocity and displacement in the whole region and a discrete Poisson equation in the fluid region.
Toxoplasma gondii is a major cause of congenital brain disease; however, the underlying mechanism of neuropathogenesis in brain toxoplasmosis remains elusive. To explore the role of T. gondii in the development of neural stem cells (NSCs), NSCs were isolated from GD14 embryos of ICR mice and were co-cultured with tachyzoites of T. gondii RH strain. We found that apoptosis levels of the NSCs co-cultured with 1×106 RH tachyzoites for 24 and 48 h significantly increased in a dose-dependent manner, as compared with the control. Western blotting analysis displayed that the protein level of C/EBP homologous protein (CHOP) was up-regulated, and caspase-12 and c-Jun N-terminal kinase (JNK) were activated in the NSCs co-cultured with the parasites. Pretreatment with endoplasmic reticulum stress (ERS) inhibitor (TUDCA) and caspase-12 inhibitor (Z-ATAD-FMK) inhibited the expression or activation of the key molecules involved in the ERS-mediated apoptotic pathway, and subsequently decreased the apoptosis levels of the NSCs induced by the T. gondii. The findings here highlight that T. gondii induced apoptosis of the NSCs through the ERS signal pathway via activation of CHOP, caspase-12 and JNK, which may constitute a potential molecular mechanism responsible for the cognitive disturbance in neurological disorders of T. gondii.
A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.
A spectral-element method is developed to solve the scattering problem for time-harmonic sound waves due to an obstacle in an homogeneous compressible fluid. The method is based on a boundary perturbation technique coupled with an efficient spectral-element solver. Extensive numerical results are presented, in order to show the accuracy and stability of the method.
High rate of charge carrier recombination is a critical factor limiting the photocatalytic activity of g-C3N4. In this contribution, we demonstrate that this issue can be alleviated by constructing a plasmonic photocatalyst with tailored plasmonic-metal nanostructures, i.e., core–shell-typed Ag@SiO2 nanoparticles. Compared with pure g-C3N4, the photocatalytic hydrogen production activity was enhanced by 63% for Ag@SiO2/g-C3N4. As analysis from the photoluminescence results, the enhancement could be attributed to that plasmonic nanostructures favored the separation of electron–hole pairs in the semiconductor due to localized surface plasmons resonance effect. It was found that the silica shell between the Ag nanoparticles and g-C3N4 was essential for the better photocatalytic activity of Ag@SiO2/g-C3N4 than that of Ag/g-C3N4 by limiting the energy-loss Förster energy transfer process.
We develop in this paper efficient and robust numerical methods for solving anisotropic Cahn-Hilliard systems. We construct energy stable schemes for the time discretization of the highly nonlinear anisotropic Cahn-Hilliard systems by using a stabilization technique. At each time step, these schemes lead to a sequence of linear coupled elliptic equations with constant coefficients that can be efficiently solved by using a spectral-Galerkin method. We present numerical results that are consistent with earlier work on this topic, and also carry out various simulations, such as the linear bi-Laplacian regularization and the nonlinear Willmore regularization, to demonstrate the efficiency and robustness of the new schemes.