Structural tuning and catalysis of tungsten carbides for the regioselective cleavage of C-O bonds

Tungsten carbides exhibit excellent performance in many heterogeneous processes because of their distinctive catalytic properties. Preparation of tungsten carbides with controllable phase composition relevant to their catalytic behavior is essential yet challenging. In this study, tungsten carbides embedded in carbon spheres (WxC@CS) were fabricated through carburization of organic–inorganic hybrid precursors. W1.25C@CS with rational structure-tuning properties exhibits promising regioselectivity (reaching 91.5%) toward aryl CO bond cleavage, specifically during hydrogenolysis of guaiacol to phenol. A structure reconstruction strategy was adopted to elucidate structure–performance relationship by transforming commercially available bulk WC from inert phase to composition-dependent active catalysts. Combined catalytic and characteristic analyses illustrate that the catalyst performance is dependent on the C-defect structure. The intimate connection between the phenol space time yield and the C/W atomic ratio on the exterior interface of the catalyst was verified. The C/W atomic ratio of 7.2 leads to the optimal catalytic performance. Density functional theory calculations were performed to define the catalytic mechanism at the atomic level. The theoretical analysis suggests an appropriate configuration of surface W and C atoms for activation of hydrogen and guaiacol molecules, rendering the intrinsic active sites for phenol production. This work provides insights into controlling the surface compositions of tungsten carbides to develop efficient CO bond cleavage catalysts, which verifies the importance of hydrogenolysis catalysis in lignin-derived compounds involving complex O-containing guaiacols and phenolics

Novel Mechano-Luminescent Sensors Based on Piezoelectric/Electroluminescent Composites

A high-sensitivity mechano-luminescent sensor was fabricated on the basis of piezoelectric/electroluminescent composites. The working principle of this mechano-luminescent sensor was elucidated by analyzing the relationship between the piezoelectric-induced charges and the electroluminescent effects. When a stress is applied on the piezoelectric layer, electrical charges will be induced at both the top and bottom sides of the piezoelectric layer. The induced electrical charges will lead to a light output from the electroluminescent layer, thus producing a mechano-luminescence effect. By increasing the vibration strength or frequency applied, the mechano-luminescence output can be obviously enhanced. Mechano-luminescence sensors have potential in smart stress-to-light devices, such as foot-stress-distribution-diagnosis systems and dynamic-load-monitors for bridge hanging cables

Human adenovirus type 7 subunit vaccine induces dendritic cell maturation through the TLR4/NF-κB pathway is highly immunogenic

IntroductionHuman adenovirus type 7 (HAdv-7) infection is the main cause of upper respiratory tract infection, bronchitis and pneumonia in children. At present, there are no anti- adenovirus drugs or preventive vaccines in the market. Therefore, it is necessary to develop a safe and effective anti-adenovirus type 7 vaccine.MethodsIn this study, In this study, we used the baculovirus-insect cell expression system to design a recombinant subunit vaccine expressing adenovirus type 7 hexon protein (rBV-hexon) to induce high-level humoral and cellular immune responses. To evaluate the effectiveness of the vaccine, we first detected the expression of molecular markers on the surface of antigen presenting cells and the secretion of proinflammatory cytokines in vitro. We then measured the levels of neutralizing antibodies and T cell activation in vivo.ResultsThe results showed that the rBV-hexon recombinant subunit vaccine could promote DC maturation and improve its antigen uptake capability, including the TLR4/NF-κB pathway which upregulated the expression of MHCI, CD80, CD86 and cytokines. The vaccine also triggered a strong neutralizing antibody and cellular immune response, and activated T lymphocytes.DiscussionTherefore, the recombinant subunit vaccine rBV-hexon promoted promotes humoral and cellular immune responses, thereby has the potential to become a vaccine against HAdv-7

The functional and structural alterations of the striatum in chronic spontaneous urticaria

The brain has long been known to be the regulation center of itch, but the neuropathology of chronic itch, such as chronic spontaneous urticaria (CSU), remains unclear. Thus, we aimed to explore the brain areas involved in the pathophysiology of CSU in hopes that our results may provide valuable insights into the treatment of chronic itch conditions. 40 CSU patients and 40 healthy controls (HCs) were recruited. Urticaria activity scores 7 (UAS7) were collected to evaluate patient’s clinical symptoms. Amplitude of low frequency fluctuations (ALFF), voxel-based morphometry (VBM), and seed-based resting-state functional connectivity (rs-FC) analysis were used to assess brain activity and related plasticity. Compared with HCs, CSU patients exhibited 1) higher ALFF values in the right ventral striatum / putamen, which were positively associated with clinical symptoms as measured by UAS7; 2) gray matter volume (GMV) increase in the right ventral striatum and putamen; and 3) decreased rs-FC between the right ventral striatum and the right occipital cortex and between the right putamen and the left precentral gyrus. Using multiple-modality brain imaging tools, we demonstrated the dysfunction of the striatum in CSU. Our results may provide valuable insights into the neuropathology and development of chronic itch

Effect of Regional vs General Anesthesia on Incidence of Postoperative Delirium in Older Patients Undergoing Hip Fracture Surgery: The RAGA Randomized Trial

Importance: In adults undergoing hip fracture surgery, regional anesthesia may reduce postoperative delirium, but there is uncertainty about its effectiveness. Objective: To investigate, in older adults undergoing surgical repair for hip fracture, the effects of regional anesthesia on the incidence of postoperative delirium compared with general anesthesia. Design, Setting, and Participants: A randomized, allocation-concealed, open-label, multicenter clinical trial of 950 patients, aged 65 years and older, with or without preexisting dementia, and a fragility hip fracture requiring surgical repair from 9 university teaching hospitals in Southeastern China. Participants were enrolled between October 2014 and September 2018; 30-day follow-up ended November 2018. Interventions: Patients were randomized to receive either regional anesthesia (spinal, epidural, or both techniques combined with no sedation; n = 476) or general anesthesia (intravenous, inhalational, or combined anesthetic agents; n = 474). Main Outcomes and Measures: Primary outcome was incidence of delirium during the first 7 postoperative days. Secondary outcomes analyzed in this article include delirium severity, duration, and subtype; postoperative pain score; length of hospitalization; 30-day all-cause mortality; and complications. Results: Among 950 randomized patients (mean age, 76.5 years; 247 [26.8%] male), 941 were evaluable for the primary outcome (6 canceled surgery and 3 withdrew consent). Postoperative delirium occurred in 29 (6.2%) in the regional anesthesia group vs 24 (5.1%) in the general anesthesia group (unadjusted risk difference [RD], 1.1%; 95% CI, -1.7% to 3.8%; P =.48; unadjusted relative risk [RR], 1.2 [95% CI, 0.7 to 2.0]; P =.57]). Mean severity score of delirium was 23.0 vs 24.1, respectively (unadjusted difference, -1.1; 95% CI, -4.6 to 3.1). A single delirium episode occurred in 16 (3.4%) vs 10 (2.1%) (unadjusted RD, 1.1%; 95% CI, -1.7% to 3.9%; RR, 1.6 [95% CI, 0.7 to 3.5]). Hypoactive subtype in 11 (37.9%) vs 5 (20.8%) (RD, 11.5; 95% CI, -11.0% to 35.7%; RR, 2.2 [95% CI, 0.8 to 6.3]). Median worst pain score was 0 (IQR, 0 to 20) vs 0 (IQR, 0 to 10) (difference 0; 95% CI, 0 to 0). Median length of hospitalization was 7 days (IQR, 5 to 10) vs 7 days (IQR, 6 to 10) (difference 0; 95% CI, 0 to 0). Death occurred in 8 (1.7%) vs 4 (0.9%) (unadjusted RD, -0.8%; 95% CI, -2.2% to 0.7%; RR, 2.0 [95% CI, 0.6 to 6.5]). Adverse events were reported in 106 episodes in the regional anesthesia group and 102 in the general anesthesia group; the most frequently reported adverse events were nausea and vomiting (47 [44.3%] vs 34 [33.3%]) and postoperative hypotension (13 [12.3%] vs 10 [9.8%]). Conclusions and Relevance: In patients aged 65 years and older undergoing hip fracture surgery, regional anesthesia without sedation did not significantly reduce the incidence of postoperative delirium compared with general anesthesia. Trial Registration: ClinicalTrials.gov Identifier: NCT02213380

An Empirical Study on the Influence of School Choice on Junior Middle School Students’ Academic Performance

Using data from 17,424 junior middle school student responses in the Chinese Education Panel Survey 2014 (CEPS 2014), this study analyzes the influence of school choice on the academic performance of primary to junior students. The results show that students whose families have a higher socioeconomic status and urban students are more likely to choose their school, and that the student’s choice of school does not make an impact on their Chinese, mathematics, foreign language or total academic scores. This indicates that choosing schools does not improve students’ academic performance. School choice increases the unequal distribution of high-quality education opportunities and reduces the efficiency of educational resources. Therefore, the government should take measures to allocate quality resources more equitably, to increase the supply of quality education resources and to guide parents and students to choose schools rationally

How Does Family Labor Promote the Ability Development of Junior High School Students?

Strengthening labor education is an indispensable part of the comprehensive development of students. However, the family, as an important field of student labor education, is failed to realize the effect. Recently, a study published in Journal of Educational Science of Hunan Normal University, on the basis of the baseline data of the China Education Panel Survey, analyzing the junior high school student’s family labor situation in China by constructing a multi-layer linear model, and then explored the relationship between family labor and the development of junior high school student's ability

Supplementary Tutoring for Compulsory Education Students in China: Status and Trends

Purpose The purpose of this paper is to explore the current status of, and developmental trends affecting, the participation in supplementary tutoring by compulsory education students in China. Design/Approach/Methods Based on the data from the China Family Panel Study (CFPS) conducted by the Peking University Institute of Social Science Survey in 2010, 2012, 2014, and 2016, the paper uses the method of multilevel linear model to comprehensively analyze problems involving a multilevel data structure. Findings The paper finds that the proportion of compulsory education students participating in supplementary tutoring (and the expenditure on such tutoring) increased annually before declining in 2016. Students with higher socioeconomic status, higher school quality, and better academic performance have a higher tutoring participation rate and also spend more on tutoring. Students in China's three northeastern provinces and eastern coastal areas have higher participation rates in tutoring and higher tutoring expenditures. Originality/Value Supplementary tutoring in China already has its own developmental patterns and trends; however, few scholars have empirically studied the developmental patterns and trends of supplementary tutoring in compulsory education based on longitudinal survey data

The Impact of High School Entrance Examination Competition on Students’ Participation in Extracurricular Tutoring in the Compulsory Education Period: An Empirical Analysis Based on the Data of China Family Panel Studies

We used the Hierarchical Linear Bernoulli Model based on China Family Panel Studies (CFPS) 2016 data and provincial high school acceptance rate data. We explored the relationship between provincial high school entrance examination competition and students’ extracurricular tutoring participation during compulsory education. The study found that the high school acceptance rate and occupational high school acceptance rate have no significant effect on the participation rate of students’ extracurricular tutoring in the compulsory education stage. However, the high school acceptance rate has a significant positive impact on the participation rate of students’ extracurricular tutoring, and there is a heterogeneous effect on the participation rate of students’ extracurricular tutoring from families of different social classes. The higher the high school acceptance rate, the greater the probability of students from families with higher social strata participating in extracurricular tutoring. The demonstration high school acceptance rate has a significant negative impact on students’ extracurricular tutoring participation rate. It has a heterogeneous influence on students’ extracurricular tutoring participation in different school stages and social class families. The education administration department should actively expand high-quality, high school educational resources and increase the demonstration high school acceptance rate. And to increase the number of admissions for the demonstration high school to disadvantaged families with lower social strata to alleviate the pressure of families and students from the high school entrance examination competition. This can not only reduce the participation rate of students’ extracurricular tutoring during the compulsory education stage, but also promote the equalization of high-quality high school entrance opportunities for children of different classes of families