Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production

The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.

网络媒介演进中“人”的进化与异化:技术与社会的互动分析

网络媒介的迭代实现了对“人”的赋权与赋能,使其从接受者、消费者进化为生产者与传播者。然而,媒介兼具技术与社会双重逻辑,复杂的政治经济历程与媒介技术演变具有互动关系。技术神话一旦进入资本、政府、市场等多方博弈的生态体系中,也难逃被工具化的厄运。本文将网络媒介的演进置于批判的政治经济与技术哲学的框架中,认为网络媒介演进的政治经济历程包括三个阶段:新自由主义与反文化助力互联网商业化;民主假象、资本逻辑与技术神话的合法耦合;从边界扩张到规则改写下的反垄断浪潮。三个阶段并非孤立,而是互有重叠,呈现出演变的总方向。与之呼应,“人”在技术流变中经历了从理想化的网络公民、参与性的社交用户(进化)与商品化的数字臣民(异化)的角色转变。

Reducing voltage hysteresis of metal oxide anodes to achieve high energy efficiency for Li-ion batteries

In the past two decades,a lot of high-capacity conversion-type metal oxides have been intensively studied as alternative anode materials for Li-ion batteries with higher energy density.Unfortunately,their large voltage hysteresis(0.8-1.2 V) within reversed conversion reactions results in huge round-trip inefficiencies and thus lower energy efficiency(50%-75%) in full cells than those with graphite anodes.This remains a long-term open question and has been the most serious drawback toward application of metal oxide anodes.Here we clarify the origins of voltage hysteresis in the typical SnO2anode and propose a universal strategy to minimize it.With the established in situ phosphating to generate metal phosphates during reversed conversion reactions in synergy with boosted reaction kinetics by the added P and Mo,the huge voltage hysteresis of 0.9 V in SnO_(2),SnO_(2)-Mo,and 0.6 V in SnO2-P anodes is minimized to 0.3 V in a ternary SnO_(2)-Mo-P(SOMP) composite,along with stable high capacity of 936 mA h g^(-1)after 800 cycles.The small voltage hysteresis can remain stable even the SOMP anode operated at high current rate of10 A g^(-1)and wide-range temperatures from 60 to 30℃,resulting in a high energy efficiency of88.5% in full cells.This effective strategy to minimize voltage hysteresis has also been demonstrated in Fe2O3,Co3O4-basded conversion-type anodes.This work provides important guidance to advance the high-capacity metal oxide anodes from laboratory to industrialization.

Effect of Mitochondrial Function of Ovarian Granulosa Cells on In Vitro Fertilization and Embryo Transfer Outcomes in Obese Polycystic Ovary Syndrome Patients

Objective:To investigate the effect of abnormal ovarian granulosa cell metabolism on in vitro fertilization and embryo transfer(IVF-ET)outcomes in obese polycystic ovary syndrome(PCOS)patients.Methods:Patients with PCOS who met the study criteria were screened according to the inclusion criteria.A total of 32 patients with obese PCOS were recruited into the study group,and 39 patients with non-obese PCOS were recruited into the control group.The general data(age,body mass index,and years of infertility),insulin resistance index(HOMA-IR),follicle-stimulating hormone(FSH),luteinizing hormone(LH),granulosa cell mitochondrial function,and IVF-ET outcome of patients in the study group and control group were retrospectively analyzed.Results:The differences in age and years of infertility between the study group and the control group were insignificant(P>0.05),and the body mass index(BMI)of the study group and control group was 30.5±1.24 kg/m2 and 22.3±1.12 kg/m2,respectively,in which the difference was statistically significant(P<0.05);the HOMA-IR of the study group was significantly higher than that of the control group(P<0.05);the reactive oxygen species(ROS)in the study group was significantly higher than that in the control group(P<0.05),and the ATP content in the study group was significantly lower than that in the control group(P<0.05);comparing the FSH and LH levels between the two groups,the difference was not statistically significant(P>0.05);the rate of IVF-ET failure was significantly higher in the study group than in the control group.Conclusion:PCOS is a complex endocrine disorder,and obesity is one of the independent risk factors for the development of PCOS.

Epidemiological Survey on Vitamin A,D,E Levels of Pregnant Women in Baoding

Objective:To understand the vitamin levels in pregnant women and its influencing factors and provide a basis for formulating scientific and reasonable vitamin supplement plans for pregnant women.Methods:Pregnant women with a pregnancy period of 12 weeks to 36 weeks in Baoding area were selected as the research subjects using the random sampling method.The sample size is estimated to be 5,000 people,and the diversity of the research subjects,such as age,education level,pregnancy,etc.,were recorded through a survey.The content of the survey included the personal information of the research subjects,pregnancy conditions,eating habits,vitamin supplements taken,etc.At the same time,blood tests were carried out on the research subjects to detect indicators such as vitamin levels.Results:The results of serum measurement showed that the vitamin A level of pregnant women was 0.38±0.12 mg/L,the vitamin E level was 13.51±3.17 mg/L,and the vitamin D level was 17.82±4.18 ng/L;the level of vitamin A of pregnant women in the first trimester was significantly lower than those in the second and third trimesters,and the level of vitamin E of pregnant women in second trimester was significantly higher than those in the first and third trimesters,with statistically significant differences(P<0.05).The rate of vitamin A deficiency in the early stage was significantly higher than that in the middle and late stages of pregnancy,(P<0.05);vitamin D deficiency existed in all pregnant women.Conclusion:Pregnant women should maintain a reasonable diet and eat more vitamin-rich foods,such as vegetables,fruits,etc.;besides,pregnant women should take vitamin supplements under the guidance of doctors or professionals according to their own conditions;moreover,the publicity and education for pregnant women should be improved with more emphasis on vitamin supplementation.

垂体促甲状腺激素腺瘤中SSTR表达谱及全数字切片自动图像分析的探索性研究

目的:探索垂体促甲状腺激素(thyroid stimulating hormone,TSH)腺瘤中生长抑素受体(somatostatin receptor,SSTR)的表达以及全数字切片自动图像分析技术的应用。方法:分析2013年1月至2019年12月北京协和医院的37例垂体TSH腺瘤的石蜡包埋组织标本及临床病理资料,利用各型SSTR1-SSTR5抗体进行免疫组织化学染色,分别进行人工判读和全数字切片自动图像分析,比较各型SSTR表达与性别、年龄、肿瘤大小、Ki-67指数以及侵袭的相关性,并对比人工判读和软件自动分析的一致性。结果:垂体TSH腺瘤中SSTR1、SSTR2、SSTR4和SSTR5多为2分和3分表达,其中3分占比均超过50.0%(4型SSTR占比依次分别为59.5%、78.4%、64.9%和56.8%)。SSTR1表达与侵袭呈明显负相关(人工r=-0.417,P=0.010;软件r=-0.406,P=0.013),并与SSTR2表达具有显著相关性(人工r=0.420,P=0.010;软件r=0.338,P=0.040)。各型SSTR表达的人工判读与图像自动分析结果均显示了较好的一致性。结论:垂体TSH腺瘤肿瘤组织中SSTR1、SSTR2、SSTR4和SSTR5均有较高水平的表达,利用基于数字化全切片的图像自动分析技术可获得与病理医师人工判读相近的评估效果。

Modeling rock specimens through 3D printing: Tentative experiments and prospects

Current developments in 3D printing （3DP） technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows： （1） compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and （2） com- pressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in produc- ing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample （such as a natural rock joint）. These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the sim- ulation of similar material modeling experiments.

Oxidative stress induces gastric submucosal arteriolar dysfunction in the elderly

AIM:To evaluate human gastric submucosal vascular dysfunction and its mechanism during the aging process.METHODS:Twenty male patients undergoing subtotal gastrectomy were enrolled in this study.Young and elderly patient groups aged 25-40 years and 60-85 years,respectively,were included.Inclusion criteria were:no clinical evidence of cardiovascular,renal or diabetic diseases.Conventional clinical examinations were carried out.After surgery,gastric submucosal arteries were immediately dissected free of fat and connective tissue.Vascular responses to acetylcholine(ACh)and sodium nitroprusside(SNP)were measured by isolated vascular perfusion.Morphological changes in the gastric mucosal vessels were observed by hematoxylin and eosin(HE)staining and Verhoeff van Gieson(EVG)staining.The expression of xanthine oxidase(XO)and manganese-superoxide dismutase(Mn-SOD)was assessed by Western blotting analysis.The malondialdehyde(MDA)and hydrogen peroxide(H2O2)content and the activities of superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)were determined according to commercial kits.RESULTS:The overall structure of vessel walls was shown by HE and EVG staining,respectively.Disruption of the internal elastic lamina or neointimal layers was not observed in vessels from young or elderly patients;however,cell layer number in the vessel wall increased significantly in the elderly group.Compared with submucosal arteries in young patients,the amount of vascular collagen fibers,lumen diameter and media cross-sectional area were significantly increased in elderly patients.Ach-and SNP-induced vasodilatation in elderly arterioles was significantly decreased compared with that of gastric submucosal arterioles from young patients.Compared with the young group,the expression of XO and the contents of MDA and H2O2in gastric submucosal arterioles were increased in the elderly group.In addition,the expression of Mn-SOD and the activities of SOD and GSH-Px in the elderly group decreased significantly compared with those in the young group.CONCLUSION:Gastric vascular dysfunction and senescence may be associated with increased oxidative stress and decreased antioxidative defense in the aging process.

养猪场户如何做好非洲猪瘟的防控

非洲猪瘟是一种急性、热性、高度接触性传染病[1],近两年来给我国养猪业带来了灾难性的影响。因此,在当前阶段做好现有养猪场户的防控工作尤为重要。文章结合我国养猪特点和防控形势,从养猪从业者角度介绍了非洲猪瘟的特点、传播方式、综合防控措施及防疫职责,以期为广大生猪养殖者做好非洲猪瘟防控提供参考。

Comprehensive optimized GM(1,1) model and application for short term forecasting of Chinese energy consumption and production

In order to improve prediction accuracy of the grey prediction model and forecast China energy consumption and production in a short term, this paper proposes a novel com- prehensively optimized GM（1,1） model, also named COGM（1,1）, based on the grey modeling mechanism. First, the relationship of the background value formula and its whitenization equation is analyzed and a new method optimizing background values is proposed to eliminate systemic errors in the modeling process. Second, the solving process of the new model is derived. For parameter estimation, a set of auxiliary parameters are used to change grey equation＇s form. Then, original parameters are re- stored by an equations system. After solving the whitenization equation, initial value in time response function is established by least errors criteria. Finally, a numerical case and comparison with other grey prediction models are made to testify the new model＇s effectiveness, and the computational results show that the COGM（1,1） model has a better property and achieves higher precision. The new model is used to forecast China energy con- sumption and production, and the ability of energy self-sufficiency is further analyzed. Results indicate that gaps between consump- tion and production in future are predicted to decline.

Prognostic value of MET, cyclin D1 and MET gene copy number in non-small cell lung cancer

The aim of this study was to analyze the correlation of the expression of MET and cyclin D1 and MET gene copy number in non-small cell lung cancer （NSCLC） tissues and patient clinicopathologic characteristics and sur- vival. Sixty-one NSCLC tissue specimens were included in the study. The expression of MET and cyclin D1 was evaluated by immunohistochemistry and MET gene copy number was assessed by quantitative real-time polymer- ase chain reaction （Q-PCR）. Positive expression of MET and cyclin D1 protein and increased MET gene copy number occurred in 59.0%, 59.0% and 18.0% of 61 NSCLC tissues, respectively. MET-positivity correlated with poor differentiation （P = 0.009）. Increased MET gene copy number was significantly associated with lymph node metastasis （P = 0.004） and advanced tumor stage （P = 0.048）, while the expression of cyclin D1 was not associ- ated with any clinicopathologic parameters. There was a significant correlation between the expression of MET and MET gene copy number （P = 0.002）. Additionally, the expression of cyclin D1 had a significant association with the expression of MET as well as MET gene copy number （P = 0.002 and P = 0.017, respectively）. MET- positivity and increased MET gene copy number were significantly associated with poor overall survival （P = 0.003 and P 〈 0.001, respectively） in univariate analysis. Multivariate Cox proportional hazard analysis confirmed that the expression of MET and MET gene copy number were prognostic indicators of NSCLC （P = 0.003 and P = 0.001, respectively）. The overexpression of MET and the increased MET gene copy number might be adverse prognostic factors for NSCLC patients. The activation of the MET/cyclin D1 signaling pathway may contribute to carcino- genesis and the development of NSCLC, and may represent a target for therapy.

High concentration of calcium ions in Golgi apparatus

The interphase NIH3T3 cells were vitally fluorescentstained with calcium indicator fluo-3 and Glogi probe C6NBD-ceramide, and then the single cells were examined by laser scanning confocal microscopy (LSCFM) for subcellular distributions of Ca2+ and the location of Golgi apparatus. In these cells, the intracellular Ca2+ were found to be highly concentrated in the Golgi apparatus. The changes of distribution of cytosolic high Ca2+ region and the Golgi apparatus coincided with the cell cycle phase.In calcium free medium, when the plasma membrane of the cells which had been loaded with fluo-3/AM were permeated by digitonin, the fluorescence of the Golgi region decreased far less than that of the cytosol. Our results indicated that the Glogi lumen retained significantly high concentration of free calcium.

NOTUM inhibition increases endocortical bone formation and bone strength

The disability,mortality and costs caused by non-vertebral osteoporotic fractures are enormous.Existing osteoporosis therapies are highly effective at reducing vertebral but not non-vertebral fractures.Cortical bone is a major determinant of non-vertebral bone strength.To identify novel osteoporosis drug targets,we phenotyped cortical bone of 3 366 viable mouse strains with global knockouts of druggable genes.Cortical bone thickness was substantially elevated in Notum?/?mice.NOTUM is a secreted WNT lipase and we observed high NOTUM expression in cortical bone and osteoblasts but not osteoclasts.Three orally active small molecules and a neutralizing antibody inhibiting NOTUM lipase activity were developed.They increased cortical bone thickness and strength at multiple skeletal sites in both gonadal intact and ovariectomized rodents by stimulating endocortical bone formation.Thus,inhibition of NOTUM activity is a potential novel anabolic therapy for strengthening cortical bone and preventing non-vertebral fractures.

H_2S对缺血再灌注引发胃黏膜损伤的作用研究

目的研究H_2S对大鼠胃缺血再灌注(gastric ischemia-reperfusion,GI-R)引发氧化应激的影响及可能机制.方法实验采用夹闭腹主动脉30 min再灌注1 h的方法建立大鼠GI-R损伤模型.在此基础上,提前给予大鼠不同浓度NaHS腹腔注射14 d预处理后,Image J分析胃黏膜损伤大体面积,采用HE染色测定胃黏膜损伤深度.分别通过试剂盒和Western blot方法检测胃黏膜组织中氧化应激相关指标.结果不同浓度的NaHS对GI-R后胃黏膜损伤的影响不同,其中10μmol/L NaHS预处理尽管不影响大鼠血浆中H_2S浓度,但显著减少GI-R诱发的胃黏膜面积和损伤深度.与GI-R组相比,NaHS预处理组中丙二醛,H_2O_2水平以及XOD,gp91^(phox),p67^(phox)表达明显降低,同时,还原性谷胱甘肽水平和SOD活性显著增加.结论外源性H_2S通过减少GI-R引起的氧化应激,对胃黏膜起保护作用.

Zr-Ti-Ni-Cu Amorphous Brazing Fillers Applied to Brazing Titanium TA2 and Q235 Steel

Ti-Zr-Cu-Ni amorphous filler with good performance is suitable for joining TC and TB titanium alloy, but its melting temperature is higher than 882.5°C, the α→β phase transition temperature of TA2, which makes the ductility of TA2 fall and the microstructure of the joint coarse. In this paper, Ti-Zr-Cu-Ni amorphous filler was redesigned and optimized by using orthogonal experiment to obtain three easy-to-use Zr-Ti-Ni-Cu amorphous fillers with low melting points and good plasticity. The fast cooling equipment was used to fabricate the brazing filler foils to implement the braze welding of TA2 and Q235 with high frequency inductance. The results indicate that all the brazing foils are amorphous structure with lower melting temperature, for example, Zr52Ti22Ni18Cu8 filler’s is 538°C. The technical parameters in brazing welding are: welding temperature T = 800°C;heating electric current I =25 A;heating time t = 15 s and holding time t = 15 s, in the case of these conditions, the jointing head shear strength of TA2/Zr52Ti24Ni13Cu11/Q235 is 139 MPa. Fracture is mainly located in the brazing seam. The white brittle intermetallic TiFe, TiFe2 and enhancement TiC spread in the center zone of brazing seam.

基于环境激励单层柱面网壳结构的模态分析

网壳结构因其杆件众多,其动力学参数频率和振型比较密集,采用力锤激振方法因其能量过小不易获取其模态参数。环境激励法不需要特别的激振设备,仅仅依赖于地脉动,信号覆盖的频带较宽,因而能够有效地识别出了复杂结构模态参数。本文基于环境激励法进行单层柱面网壳结构模型的模态分析并与有限元模态分析结构比较,验证了基于环境激励模态分析的有效性。

Revealing the structure design of alloyed based electrodes for alkali metal ion batteries with in situ TEM

Alloyed based anode materials with high theoretical specific capacity and low reaction potential are considered to be highly potential high-energy density anode materials for alkali metal ion batteries(AMIBs).Thus,the design of alloyed based materials with high electrochemical performance has attracted great attention.Among the numerous characterization methods for guiding electrode materials design,in situ transmission electron microscopy(TEM)gradually plays an irreplaceable role due to its high temporal and spatial resolution in directly observing the change of morphology,crystal structure and element evolutions.Herein,we reviewed the two current research hotspots and mainly focused on the structure design of alloyed based electrode material under the guidance of in situ TEM.Specifically,various nanostructure designs of alloyed based electrode materials with guidance of in situ TEM were employed to solve the key scientific issues of the violent volume change during alloying/dealloying processes for enhanced electrochemical performances.Mainly through introducing buffer space in the electrode material to reduce volume change to improve structural stability,including porous structure(0 D),nanotube structure(1 D),simple hollow structure,yolk-shell structure and some hybrid hollow structures(3 D).Furthermore,the direct guidance of in situ TEM is expected for creating new opportunities to nextgeneration electrode material design for AMIBs.

针尖增强拉曼活性探针的快速制备与判定

探针的质量是实现高信号增益以及高分辨针尖增强拉曼实验的关键.本文报道了一种通过在原子尺度上改变探针尖端形貌来可控制备针尖增强拉曼活性探针的方法,并提出了两个重要的准则来原位判断用于针尖增强拉曼实验探针的针尖增强拉曼活性.一个判据是利用第一镜像势峰位向低能量的移动来监测远场入射激光与近场等离激元之间的耦合,另一个判据是根据与探针尖端原子级突起相关的低波数拉曼峰的出现来判断从近场到远场辐射的耦合效率.该研究为在目标分子和其他材料上进行真正的针尖增强拉曼实验之前快速制备和判断针尖增强拉曼活性探针提供了一种有效的方法,有望为针尖增强拉曼等探针增强光谱技术的发展提供帮助.

Laser cooling of CH molecule: Insights from ab initio study

The feasibility of laser cooling a CH molecule is investigated theoretically by employing the ab initio method. The potential energy curves for the five ∧-S states and eight Ω states of CH are determined by the multi-reference configuration interaction with the Davidson corrections（MRCI＋Q） level of theory. The results agree well with the available experimental data and other theoretical values. Also, the permanent dipole moments and transition dipole moments of the CH molecule are calculated at the multi-reference configuration interaction（MRCI） level. We find highly diagonally distributed FranckCondon factors（f00 = 0.9950 and 0.9998） and branching ratios（R00 = 0.983 and 0.993） for the A^2△→ X2Π and C^2∑^＋→X^2Π transitions. Moreover, the values of suitable radiative lifetime τ of the A2 A and C^2∑^＋ states are evaluated to be9.64×10^-7 s and 2.02×10^-7 s, respectively, for rapid laser cooling. A scheme for laser cooling the CH molecule is designed. In the proposed cooling scheme, three wavelengths for A^2△→X^2Π and C^2∑^＋→X^2Π transitions are used, and the main pump lasers are λ00=430.86 nm and 313.45 nm, respectively. The feasibility of laser cooling the CH molecules is demonstrated for each of these schemes, and this study offers a theoretical basis for experimental research into preparation of cold CH molecules.

B7-H1在膀胱癌患者外周血树突状细胞中的表达及其临床意义(英文)

Objective:The aim of this study was to study the expression and the clinical significance of B7-H1 on dendritic cells (DCs) in peripheral blood from patients with bladder cancer. Methods:Peripheral blood mononuclear cell were disparted from 30 bladder cancer patients and 7 healthy controls by density gradient centrifugation and then co-cultured. The expression of B7-H1 on DCs were analyzed by flow cytometry. Results:Expression of B7-H1 on DCs in bladder cancer was higher than healthy controls (P<0.01). And the expression were strongly associated with the pathological grade and clinical stage of bladder cancer (P<0.05). Conclusion:The up-regulation of B7-H1 on DCs was strongly associated with neoplastic progression of bladder cancer. B7-H1/programmed death (PD)-1 signal pathway may also play an important role in immune escape of bladder cancer during initial phase of T cell immune response.