The development of electrocatalysts plays a pivotal role in electrocatalytic reactions because the catalyst determines not only the overall reaction efficiency but also the cost. Carbon materials ...with good electrical conductivity and large surface area have been used as efficient electrocatalyst supports for a wide range of electrocatalyses. Recently, it has been realized that carbons themselves are also promising nonmetal electrocatalysts. In this regard, the electrocatalytic activities of carbons can be tailored by surface modification or building in particular dopants/defects. In the accumulation of the profound knowledge of the electrocatalytic nature and the technological advances, there is increasing interest in developing carbon-based catalysts for various applications. In this review, we summarize the recent progress in the rational design and preparation of graphitic carbon-based materials for advanced electrocatalysis including oxygen reduction and evolution reactions, hydrogen evolution reaction, and carbon dioxide reduction, to provide deep insights into the electrocatalysis for advanced energy conversion and storage.
The recent development of carbon-based catalysts for advanced electrocatalysis is summarized and discussed.
Using 2.93 fb −1 of e+e− collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector, we report the first measurements of the absolute branching fractions of 14 hadronic ...D0(+) decays to exclusive final states with an η , e.g., D0 → K−π+η , K0Sπ0η , K+K−η , K0SK0Sη, K−π+π0η , K0Sπ+π−η , K0Sπ0π0η , and π+π−π0η ; D+ → K0Sπ+η,K0SK+η, K−π+π+η, K0Sπ+π0η, π+π+π−η , and π+π0π0η. Among these decays, the D0 → K−π+η and D+→K0Sπ+η decays have the largest branching fractions, which are B (D0 → K−π+η) = ( 1.853 ± 0.02 5 stat ± 0.03 1 syst ) % and B ( D+ → K0Sπ+η ) = ( 1.309 ± 0.03 7 stat ± 0.03 1 syst ) % , respectively. The charge-parity asymmetries for the six decays with highest event yields are determined, and no statistically significant charge-parity violation is found.
Mesoporous anatase (TiO₂) was modified with silver (Ag) nanoparticles using a photoreduction method. Performance of the resulting TiO₂–Ag nanocomposites for water purification was evaluated using ...degradation of Rhodamine B (RhB) and disinfection of Escherichia coli (E. coli) under ultraviolet (UV) irradiation. The composites with different Ag loadings were characterized using physical adsorption of nitrogen, X-ray diffraction, X-ray photoelectron spectroscopy and UV–Visible diffuse reflectance spectroscopic techniques. The results showed that metallic Ag nanoparticles were firmly immobilized on the TiO₂ surface, which improved electron-hole separation by forming the Schottky barrier at the TiO₂–Ag interface. Photocatalytic degradation of RhB and inactivation of E. coli effectively occurred in an analogical trend. The deposited Ag slightly decreased adsorption of target pollutants, but greatly increased adsorption of molecular oxygen with the latter enhancing production of reactive oxygen species (ROSs) with concomitant increase in contaminant photodegradation. The optimal Ag loadings for RhB degradation and E. coli disinfection were 0.25 wt% and 2.0 wt%, respectively. The composite photocatalysts were stable and could be used repeatedly under UV irradiation.
Abnormal proliferation, apoptosis repression and differentiation blockage of hematopoietic stem/progenitor cells have been characterized to be the main reasons leading to acute myeloid leukemia ...(AML). Previous studies showed that miR-29a and miR-29b could function as tumor suppressors in leukemogenesis. However, a comprehensive investigation of the function and mechanism of miR-29 family in AML development and their potentiality in AML therapy still need to be elucidated. Herein, we reported that the family members, miR-29a, -29b and -29c, were commonly downregulated in peripheral blood mononuclear cells and bone marrow (BM) CD34+ cells derived from AML patients as compared with the healthy donors. Overexpression of each miR-29 member in THP1 and NB4 cells markedly inhibited cell proliferation and promoted cell apoptosis. AKT2 and CCND2 mRNAs were demonstrated to be targets of the miR-29 members, and the role of miR-29 family was attributed to the decrease of Akt2 and CCND2, two key signaling molecules. Significantly increased Akt2, CCND2 and c-Myc levels in the AML cases were detected, which were correlated with the decreased miR-29 expression in AML blasts. Furthermore, a feed-back loop comprising of c-Myc, miR-29 family and Akt2 were found in myeloid leukemogenesis. Reintroduction of each miR-29 member partially corrected abnormal cell proliferation and apoptosis repression and myeloid differentiation arrest in AML BM blasts. An intravenous injection of miR-29a, -29b and -29c in the AML model mice relieved leukemic symptoms significantly. Taken together, our finding revealed a pivotal role of miR-29 family in AML development and rescue of miR-29 family expression in AML patients could provide a new therapeutic strategy.
Previous mass screening studies have shown that IgA antibodies against Epstein–Barr Virus (EBV) can facilitate early detection of nasopharyngeal carcinoma (NPC), but the impact of EBV-antibody ...screening for NPC-specific mortality remains unknown.
A prospective, cluster randomized, controlled trial for NPC screening (PRO-NPC-001) was conducted in 3 selected towns of Zhongshan City and 13 selected towns of Sihui City in southern China beginning in 2008. Serum samples of the screening group were tested for two previously selected anti-EBV antibodies. Subjects with serological medium risk were subsequently retested annually for 3 years, and those with serological high risk were referred to otorhinolaryngologists for diagnostic check-up. An interim analysis was carried out to evaluate the primary end points of the NPC-specific mortality and the early diagnostic rate, and the secondary end point of the NPC incidence, through linkage with the database of Zhongshan City.
Among 70 296 total subjects, 29 413 screened participants (41.8% of the total subjects) in the screening group and 50 636 in the control group, 153 (43.3 per 100 000 person-year), 62 (55.3 per 100 000 person-year) and 99 (33.1 per 100 000 person-year) NPC cases were identified. The early diagnostic rates of NPC were significantly higher in the participants (79.0%, P < 0.0001) and the screening group (45.9%, P < 0.0001) compared with the control group (20.6%). Although no differences were found between NPC-specific mortality of the screening group and the control group relative risk (RR)= 0.82, 95% confidence interval (CI) 0.37–1.79, lower NPC-specific mortality was noticed among participants from the screening group versus the control group (RR = 0.22, 95% CI 0.09–0.49).
IgA antibodies against EBV can identify high-risk population and was effective in screening for early asymptomatic NPC. Although the mortality reduction was not significant in the primary end point, we noted encouraging evidence of a mortality reduction in screening participants in this interim analysis.
NCT00941538.
China has implemented a large number of major infrastructure projects (MIPs) over the last three decades. Social responsibility management is crucial for MIPs' sustainable development. What is social ...responsibility of major infrastructure (MIP-SR)? To answer this question, this article proposes the concept and key issues of major infrastructure projects' social responsibility (MIP-SR) and develops a comprehensive conceptual framework for MIP-SR, which covers three dimensions: (i) project life-cycle dynamics; (ii) stakeholder's heterogeneity and (iii) social responsibility interactivity. The three-dimensional framework provides a systematic framework for MIP-SR's academic research and practical implementation, which in turn promotes the sustainable development of MIPs.
•We propose a concept of major infrastructure projects' social responsibility (MIP-SR).•We describe major conflicts in MIP-SR and key issues of MIP-SR.•We develop a three-dimension conceptual framework for MIP-SR.•MIP-SR covers three dimensions: dynamics, heterogeneity, and interactivity.
In this paper, Ag contained in the lead-silver slag was recovered during the melt-vaporization process. The existing Ag state in the soot was analyzed, the influence of the reaction temperature, the ...carbon ratio, and the reaction time on the removal rate of the silver was investigated, and the process conditions were optimized using reaction surface methodology. Silver chloride, silver metal, silver sulfide, silver oxide, and silver sulfate are the main silver phases in lead-silver slag, of which silver chloride and silver sulfide are the main phases. The silver oxide (Ag2O) and the silver chloride (AgCl) in the leadsilver slag volatilize to soot, the silver sulfide (Ag2S) is oxidized by oxygen to silver sulfate (Ag2SO4), and elemental silver volatilizes with Pb and Zn to form alloys. The silver is ultimately present as Ag, AgCl, Ag2O and Ag2SO4 in the soot. The removal rate of the silver gradually increases with increasing reaction temperature and tends to remain stable at 1300?C. With a gradual increase in the carbon content, the removal rate of silver first increases and then decreases. The highest value is 80.12 wt% when the carbon content is 16.30 wt%. As the holding time increases, the silver removal rate gradually increases and then stabilizes at 79.97 wt% even at a holding time of 150 minutes. The optimum process conditions for silver removal are a reaction temperature of 1340?C, a carbon content of 16.10 wt%, and a holding time of 165 minutes. The average removal rate of silver under these conditions is 80.42 wt%. The research in this article provides a theoretical basis for the removal and utilization of silver from lead and silver residues.
Using a sample of about 10(10) J/Psi events collected at a center-of-mass energy root s = 3.097 GeV with the BESIII detector, the electromagnetic Dalitz decays J/Psi -> e(+)e(-) pi(+)pi(-) eta', ...with eta' -> gamma pi(+)pi(-) and eta' -> pi(+)pi(-) eta, have been studied. The decay J/Psi -> e(+)e(-) X(1835) is observed with a significance of 15 sigma, and also an e(+)e(-) invariant-mass dependent transition form factor of J/Psi -> e(+)e(-) X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the pi(+)pi(-) eta' invariant-mass spectrum with significances of 5.3 sigma and 7.3 sigma. The corresponding product branching fractions for J/Psi -> e(+)e(-) X, X -> pi(+) pi(-) eta' X = X(1835), X(2120), and X(2370) are reported.
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