Amine-functionalized hierarchically porous carbon supported Pd nanocatalysts for highly efficient H2 generation from formic acid with fast-diffusion channels

Formic acid(FA)has come to be considered a potential candidate for hydrogen storage,and the development of efficient catalysts for H2releasing is crucial for realizing the sustainable process from FA.Herein,we have developed the ultrafine Pd nanoparticle(NPs)with amine-functionalized carbon as a support,which was found to show an excellent catalytic activity in H_(2)generation from FA dehydrogenation.The synergetic mechanism between amine-group and Pd active site was demonstrated to facilitate H2generation byβ-hydride elimination.Moreover,the texture of support for Pd NPs also plays an important role in determining the reactivity of FA,since the diffusion of gaseous products makes the kinetics of diffusion as a challenge in this high performance Pd catalysts.As a result,the as-prepared Pd/NH_(2)-TPC catalyst with the small sized Pd nanoparticles and the hierarchically porous structures shows a turnover of frequency(TOF)value of 4312 h^(-1)for the additive-free FA dehydrogenation at room temperature,which is comparable to the most promising heterogeneous catalysts.Our results demonstrated that the intrinsic catalytic activities of active site as well as the porous structure of support are both important factors in determining catalytic performances in H2generation from FA dehydrogenation,which is also helpful to develop high-activity catalysts for other advanced gas-liquid-solid reactions systems.

推进“精准资助”:义务教育学生资助管理绩效评估研究——基于第三方教育评估机构的数据分析

学生资助工作是国家"精准扶贫"、"消灭贫困县"的有机组成部分,也是保证学生受教育权利和基本人权的重要体现,对义务教育学生资助管理绩效评估则是政府部门推进"精准资助"的有效措施。本文依据第三方教育评估机构获得的实证评估数据,针对全国34个省级单位2014年度义务教育资助管理绩效情况,深入分析了我国义务教育学生资助管理的成绩与问题。评估结果显示:在资助管理成效方面,义务教育资助政策体系逐步完善,学生资助的项目范围不断增加,学生资助的覆盖面和数量不断扩大,各级部门资助资金落实效果明显,有力保证了义务教育阶段学生受教育的机会和权利;在资助管理问题方面,部分地方资金配套指标完成不足,省级管理机构监督检查力度不到位,学生资助政策宣传的落实环节存在缺失,信息管理工作重视程度不够等,这些问题在今后进一步推进义务教育"精准资助"工作中亟待改进。

超声引导下空芯针和针吸活检对乳腺癌内乳淋巴结诊断价值的比较

目的:评估超声引导下空芯针活检(core needle biopsy,CNB)和针吸活检(fine needle aspiration,FNA)对乳腺癌内乳淋巴结(internal mammary node,IMN)转移的诊断价值。方法:回顾性分析2012年5月至2020年10月河北医科大学第四医院496例行超声引导下IMN穿刺的乳腺癌患者临床资料,其中CNB组374例、FNA组122例,采用一致性Kappa检验分析CNB、FNA的诊断效能,计算诊断的敏感度、特异度等指标。亚组分析不同大小及类型IMN的CNB、FNA诊断效能及影响标本满意度的因素。结果:CNB组和FNA组穿刺标本不满意度分别为5.6%(21/374)和3.3%(4/122),差异无统计学意义(P>0.05)。剔除不满意标本后比较CNB、FNA的诊断效能,其Kappa值分别为0.817、0.907。亚组分析显示IMN厚径<0.5 cm组和0.5~0.9 cm组中,CNB、FNA的Kappa值分别为0.877、1.000和0.772、0.783(均P<0.01);IMN厚径≥1.0 cm组中,CNB组的假阴性率为3.4%(1/29),FNA组无假阴性。结论:对于IMN定性诊断,FNA诊断效能更高,由于IMN一般较小且位置特殊,FNA也是更安全的穿刺方法。

基于流动化学平台的3-(2-羟基苯基)-1-(吡啶-3-基)丙-2-烯-1-酮合成实验改进

流动化学技术相较于传统间歇式反应,具有高传热与传质效率、高反应安全性、短反应时间以及可精准控制反应参数等优点,从而成为有机合成中最具潜力的技术之一。国外多所高校已经开设流动化学相关课程实验,而我国相关课程实验仍处于起步阶段。本实验将传统有机实验中Claisen-Schmidt反应合成查尔酮衍生物进行改进,通过搭建液相-液相流动化学反应平台进行流动化学合成,并通过紫外-可见光谱仪对反应过程进行监测。该实验在实现相同教学目的下,具有反应时间短、现象明显、碱用量少等显著优势。

高校大学生创业行业特点及差异分析——基于第二、三产业的比较视角

本文基于2018年全国21个省级行政区域抽样调查数据,以第二、三产业比较视角,从创业企业现状和发展前景两个维度对高校大学生创业行业特点、差异进行统计分析。研究发现:高校大学生创业类型主要是信息技术服务企业,规模整体属于中型或小型企业,虽然与互联网等新兴技术紧密结合,但高新技术企业占比较低;企业所在行业存在着激烈的竞争,产品或技术却并无明显竞争优势,整体盈利状况并不理想;第二、三产业的创业企业分别在创业时长、启动资金来源、企业规模、行业竞争和融资阶段存在显著差异,近3年内,大学生更倾向选择第三产业创业,所处的行业竞争程度高于第二产业,盈利情况低于第二产业。为提升大学生创业成功率,政府应加强大学生创业项目行业选择引导,落实大学生创业优惠政策;高校应明确创业教育的价值定位,结合经济社会转型升级改革创业教育模式;创业大学生应接受系统的创业教育,做好创业前期行业调查研究。

Sinomenine reduces iNOS expressionvia inhibiting the T-bet IFN-γ pathway in experimental autoimmune encephalomyelitis in rats

Sinomenine is a bioactive alkaloid isolated from the Chinese medicinal plant Sinomenium acutum. It is widely used as an immunosuppressive drug for treating rheumatic and arthritic diseases. In our previous studies, we found that sinomenine reduced cellular infiltration within the spinal cord and alleviated experimental autoimmune encephalomyelitis （EAE） in rats. In this study, we further investigated the mechanisms of sinomenine treatment in EAE rats. In EAE rats, treatment with sinomenine exerted an anti-inducible NO synthase （anti-iNOS） effect, which is related to the reductions of Thl cytokine interferon-y （IFN-7） and its transcription factor, T-bet, in spinal cords. Moreover, sinomenine treatment of splenocytes stimulated with anti-CD3 antibody and recombinant rat in- terleukin 12 reduced the expression of T-bet and IFN-y in vitro and also reduced the capability of supernatants of splenocyte culture to induce iNOS expression by primary astrocytes. However, sinomenine had no direct inhibito- ry effect on iNOS produced by astrocytes cultured with IFN-y and tumor necrosis factor α in vitro. In conclusion, the anti-iNOS effect of sinomenine on EAE is mediated via the suppression of T-bet/IFN-y pathway.

Increased serum IL-10 in lupus patients promotes apoptosis of T cell subsets via the caspase 8 pathway initiated by Fas signaling

We sought to investigate the expression of Fas and FasL on T cell surface and caspase 8 involvement in T cell apoptosis promoted by serum IL-10 in systemic lupus erythematosus （SLE） patients. Cells and sera were obtained from 35 SLE patients. Apoptosis of T cells in patients with SLE was increased and associated with the SLE disease activity index （SLEDAI）. Elevated expression of Fas and FasL on T cell surface contributed to increased apoptosis of T cells. Increased IL-10 in the sera of SLE patients was capable of inducing Fas and FasL expression on CD4^＋T cell surface, promoting apoptosis of this cell subset. Decreased IL-10 serum levels and low expression of Fas were found in 5 patients of the first follow-up group after 2-month treatment. In another group with one-year treatment, the SLEDAI declined to inactive scores. Serum IL-10 was decreased significantly, and expression of Fas and FasL on T cells was also reduced. Declined apoptosis was predominant only in CD4^＋T cell subset. When sera with high level of IL-10 were used to culture PBMCs from healthy controls, activated caspase 8 was elevated in CD3^＋T, CD4^＋T and CD8^＋T cells. The study showed that serum IL-10 induced apoptosis of T cell subsets via the caspase 8 pathway initiated by Fas signaling. Increased apoptosis of T cells contributes to autoantigen burden, which is pathogenic in the development of SLE.

Serum IL-10 from systemic lupus erythematosus patients suppresses the differentiation and function of monocyte-derived dendritic cells

The role played by cytokines, other than interferon （IFN）-a, in the differentiation and function of dendritic cells （DCs） in systemic lupus erythematosus （SLE）, remains unclear. Serum interleukin-10 （IL-10） levels are generally elevated in SLE patients, which might modulate the differentiation of DCs. In this study, DCs were induced from monocytes either by transendothelial trafficking or by culture with granulocyte-macrophage colony-stimulating factor （GM-CSF） ＋ IL-4 ＋ tumor necrosis factor （TNF）-a. Both systems were used to investigate the effects of elevated serum IL-10 level on DC differentiation in SLE patients. The results showed that monocyte-derived DCs induced by either SLE serum or exogenous IL-10 reduced the expression of human leukocyte antigen （HLA）-DR and CD80, decreased IL-12p40 level, and increased IL-10 level, and exhibited an impaired capacity to stimulate allogenic T-cell proliferation. These results indicate that serum IL-10 may be involved in the pathogenesis of SLE by modulating the differentiation and function of DCs.

XRCC1 Arg399Gln and Arg194Trp polymorphisms regulate XRCC1 expression and chemoresistance of non-small cell lung cancer cells

X-ray repair cross-complementing protein 1(XRCC1)could repair cisplatin-induced DNA damage.XRCC1 Arg399Gln and Arg194Trp variants alter XRCC1 expression and function,leading to changes in cancer sensitivity to cisplatin treatment.This study aimed to investigate the effects of XRCC1 Arg399Gln and Arg194Trp polymorphisms on cell viability,apoptosis and XRCC1 expression in cisplatin-sensitive A549 and cisplatin-resistant A549/DDP non-small cell lung cancer(NSCLC)cells.Plasmids carrying XRCC1 Arg399Gln and Arg194Trp were constructed and transfected into A549 and A549/DDP cells.RT-PCR,Western blot,MTT assay,and flow cytometry analysis were performed to assess cell viability,apoptosis,and XRCC1 expression.Compared to control cells,the viability of A549 and A549/DDP cells transfected with XRCC1 Arg399Gln and Arg194Trp was higher and the apoptosis rate was lower,and XRCC1 mRNA and protein expression levels were significantly higher.In conclusion,our results suggest that XRCC1 Arg399Gln and Arg194Trp polymorphisms change XRCC1 expression in NSCLC cells and alter the sensitivity of NSCLC to cisplatin-based chemotherapy.

Pathological significance and regulatory mechanism of lymphotoxin β receptor overexpression in T cells of patients with systemic lupus erythematosus

Systemic lupus erythematosus（SLE） is a typical autoimmune disease. Lymphotoxin β receptor（LTβR） signaling plays an important role in autoimmune inflammations. LTβR-Ig fusion protein, LTβR blocking agent, has been used to treat SLE, while its mechanism remains to be fully elucidated. In this study, to investigate the expression of LTβR in the T cells of SLE patients and its roles in the pathogenesis of SLE, we isolated the peripheral blood T cells of SLE patients and normal controls to detect expression of LTβR by flow cytometry and RNA assay. T cells were also stimulated with LIGHT, a ligand of LTβR, and then detected for their LTβR expressions and apoptosis by flow cytometry. Also, their expressions of inflammatory factors and receptors were determined by RNA assay. The results showed that LTβR positive cells were 22.75%±6.98% in CD3~＋ cells of SLE patients, while there were almost no LTβR positive cells in CD3~＋ cells of normal persons. Moreover, LTβR expression was remarkably higher in CD3,CD4 and CD8 positive T cells of active SLE patients than non/low active patients（all P〈0.05）, and positively correlated with increased Ig level, decreased complement level and renal damage. Moreover, the stimulation of SLE T cells with LIGHT promoted higher expression of LTβR, IL-23 R and IL-17 A, and apoptosis of T cells. In conclusion,we demonstrated a high expression of LTβR in the T cells of SLE patients which may be associated with pathogenesis of SLE.

Lactobacillus isolates from healthy volunteers exert immunomodulatory effects on activated peripheral blood mononuclear cells

As probiotics in the gut, Lactobacilli are believed to play important roles in the development and maintenance of both the mucosal and systemic immune system of the host. This study was aimed to investigate the immunomodulatory function of candiate lactobacilli on T cells. Lactobacilli were isolated from healthy human feces and the microbiological characteristics were identified by API 50 CHL and randomly amplified polymorphic DNA （RAPD） assays. Anti-CD3 antibody activated peripheral blood mononuclear cells （PBMCs） were treated by viable, heat-killed lactobacilli and genomic DNA of lactobacilli, and cytokine profiles were tested by ELISA. Isolated lactobacilli C44 and C48 were identified as L. acidophilus and L. paracacei, which have properties of acid and bile tolerance and inhibitor effects on pathogens. Viable and heat-killed C44 and C48 induced low levels of proinflammatory cytokines （TNF-a, IL-6 and IL-8） and high levels of IFN-y and IL-12p70 in PBMCs. In anti- CD3 antibody activated PBMCs, viable and heat-killed C44 increased Th2 cytokine levels （IL-5, IL-6 and IL-10）, and simultaneously enhanced Thl responses by inducing IFN-y and IL-12p70 production. Different from that of lactabacillus strains, their genomic DNA induced low levels of IL-12p70, IFN-y and proinflammatory cytokines in PBMCs with or without anti-CD3 antibody activation. These results provided in vitro evidence that the genomic DNA of strains of C44 and C48, especially C44, induced weaker inflammation, and may be potentially applied for treating allergic diseases.

城市低空无人机飞行计划协同推演与优化调配方法

针对复杂城市环境下无人机集群飞行面临的多机耦合制约、冲突风险频发和运行效率低下等难题,提出了城市低空无人机飞行计划协同推演与最优调配方法。首先,面向无人机“个体”,考虑无人机与城市静态环境目标之间的冲突问题,构建了基于概率风险地图的无人机三维路径规划方法,实现了无人机飞行计划“初始生成”;然后,面向无人机“群体”,考虑无人机与无人机之间的冲突问题,构建了无人机飞行计划多类型冲突协同推演模型,设计并度量了冲突发生率、冲突风险等级和栅格占用比例等冲突特征指标;最后,设计了调整飞行路径、飞行速度、飞行时间等多元化调配策略,建立了基于多元策略自适应配置的无人机飞行计划优化调配模型,验证了所提方法的优化性能和参数敏感性,实现了不同交通密度场景下城市低空无人机飞行计划的优化调配。实验表明,所提方法可在有效控制风险成本和时间成本的基础上,将飞行计划冲突降低96.2%,对于40架以内的无人机运行场景,可得到完全无冲突的飞行计划,而100架以内的无人机最低飞行冲突解脱率可控制在95%以上。所提方法是科学有效的,可为复杂城市低空无人机飞行活动安全和高效管理提供理论基础和方法指导。

Effect of Interferon-alpha in systemic lupus erthematosus (SLE) serum on the differentiation and maturation of dendritic cells derived from CD34^+ hematopoietic precursor cells

Objective： To study the effect of interferon-alpha IFN-α in the serum of SLE patients on the differentiation and maturation of dendritic cells （DCs） derived from CD34^＋ hematopoietic precursor cells （HPCs）. Methods： Serum samples from SLE patients and normal controls were collected and the concentration of IFN-α detected by ELISA. CD34^＋HPCs were purified from cord blood by a magnetic cell sorting system （MACS）, and cultured to differentiate to DCs. Normal serum, normal serum with exogenous IFN-α, SLE serum with raised levels of IFN-α, or SLE serum with anfi-IFN-α neutralizing antibody was added to the culture medium. The phenotype of DCs was analyzed by flow cytometry （FCM） and the capacity of DCs to stimulate allogenic T lymphocyte proliferation was evaluated in a mixed lymphocyte reaction by the Cell Counting Kit-8. Cytokine production was assessed by ELISA. Results： Serum levels of IFN-α were significantly higher in SLE patients than in normal controls and this correlated positively with disease activity. Cultured in SLE serum with raised levels of IFN-α, CD34^＋ HPCs could differentiate into DCs that expressed higher levels of HLA-DR, CD80 and CD86, and showed an enhanced allogenic T-cell stimulatory capacity, while producing lower levels of IL-12 and higher amounts of IL-10 compared with those DCs cultured in normal serum. Conclusion： Increased levels of IFN-α in SLE serum promotes the differentiation and maturation of DCs derived from CD34^＋ HPCs and could contribute to the pathogenesis of SLE.

Research progress on electrolytes for fast-charging lithium-ion batteries

Fast-charging is considered to be a key factor in the successful expansion and use of electric vehicles.Current lithium-ion batteries(LIBs)exhibit high energy density,enabling them to be used in electric vehicles(EVs)over long distances,but they take too long to charge.In addition to modifying the electrode and battery structure,the composition of the electrolyte also affects the fast-charging capability of LIBs.This review provides a comprehensive and in-depth overview of the research progress,basic mechanism,scientific challenges and design strategies of the new fast-charging solution system,focusing on the influences that the compositions of liquid and solid electrolytes have on the fast-charging performance of LIBs.Finally,new insights,promising directions and potential solutions for the electrolytes of fast-charging systems are proposed to stimulate further research on revolutionary next-generation fastcharging LIB chemistry.

Effectiveness of COVID-19 Vaccination Against SARS-CoV-2 Omicron Variant Infection and Symptoms—China,December 2022–February 2023

Summary What is already known about this topic?A considerable percentage of the population has received both primary and booster vaccinations,which could potentially provide protection against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron infections and related symptoms.What is added by this report?The self-reported infection rate,as determined from an online survey,reached its peak(15.5%)between December 19 and 21,2022,with an estimated 82.4%of individuals in China being infected as of February 7,2023.During the epidemic,the effectiveness of booster vaccinations against SARS-CoV-2 Omicron infection was found to be 49.0%within three months of vaccination and 37.9%between 3 and 6 months following vaccination.Furthermore,the vaccine effectiveness of the booster vaccination in relation to symptom prevention varied from 48.7%to 83.2%within three months and from 25.9%to 69.0%between 3 and 6 months post-booster vaccination.