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1β受体阻滞剂在中国高危冠心病患者中的应用现状调查显示文摘目的:了解国内高危冠心病(CHD)患者β受体阻滞剂的使用现状,分析与用药相关的影响因素。方法:借助一项国际多中心大规模临床试验在中国实施之际,分别于2007年及2009年在14个城市的51家医院进行调查,对符合条件的CHD患者,利用电子问卷采集临床资料,对经临床试验证实且明确推荐用于二级预防的几种药物的使用情况进行统计描述和分析。本文将重点分析其中的β受体阻滞剂使用情况。结果:本调查共纳入13 078例CHD患者,均有服用β受体阻滞剂的适应证,但服用β受体阻滞剂的比例仅为60%,心肌梗死后患者服用β受体阻滞剂的比例也仅为61.9%。曾接受冠状动脉血管重建术的患者及伴有高血压的患者β受体阻滞剂用药比例较高。各种β受体阻滞剂中,美托洛尔和比索洛尔使用最为广泛。结论:国内CHD患者目前β受体阻滞剂的使用状况与指南要求存在差距,如何将循证医学证据与临床实践有机结合,让尽可能多的患者从中受益,仍是临床工作者及卫生决策部门面临的重大问题。张海波 张丹 李静 李希 冯芳 刘佳敏 高岩 乌汉毕力格 葛蕾 庞鑫 CHEN Yiping CHEN Zhengming LANDRAY Martin ARMITAGEJane CHEN Fang 蒋立新 2011临床心血管病杂志2011,27,6:25
2Multimorbidity patterns and association with mortality in 0.5 million Chinese adults显示文摘Background:Few studies have assessed the relationship between multimorbidity patterns and mortality risk in the Chinese population.We aimed to identify multimorbidity patterns and examined the associations of multimorbidity patterns and the number of chronic diseases with the risk of mortality among Chinese middle-aged and older adults.Methods:We used data from the China Kadoorie Biobank and included 512,723 participants aged 30 to 79 years.Multimorbidity was defined as the presence of two or more of the 15 chronic diseases collected by self-report or physical examination at baseline.Multimorbidity patterns were identified using hierarchical cluster analysis.Cox regression was used to estimate the associations of multimorbidity patterns and the number of chronic diseases with all-cause and cause-specific mortality.Results:Overall,15.8%of participants had multimorbidity.The prevalence of multimorbidity increased with age and was higher in urban than rural participants.Four multimorbidity patterns were identified,including cardiometabolic multimorbidity(diabetes,coronary heart disease,stroke,and hypertension),respiratory multimorbidity(tuberculosis,asthma,and chronic obstructive pulmonary disease),gastrointestinal and hepatorenal multimorbidity(gallstone disease,chronic kidney disease,cirrhosis,peptic ulcer,and cancer),and mental and arthritis multimorbidity(neurasthenia,psychiatric disorder,and rheumatoid arthritis).During a median of 10.8 years of follow-up,49,371 deaths occurred.Compared with participants without multimorbidity,cardiometabolic multimorbidity(hazard ratios[HR]=2.20,95%confidence intervals[CI]:2.14-2.26)and respiratory multimorbidity(HR=2.13,95%CI:1.97-2.31)demonstrated relatively higher risks of mortality,followed by gastrointestinal and hepatorenal multimorbidity(HR=1.33,95%CI:1.22-1.46).The mortality risk increased by 36%(HR=1.36,95%CI:1.35-1.37)with every additional disease.Conclusion:Cardiometabolic multimorbidity and respiratory multimorbidity posed the highest threat on mortality risk and deserved particular attention in Chinese adults.Junning Fan Zhijia Sun Canqing Yu Yu Guo Pei Pei Ling Yang Yiping Chen Huaidong Du Dianjianyi Sun Yuanjie Pang Jun Zhang Simon Gilbert Daniel Avery Junshi Chen Zhengming Chen Jun Lyu Liming Li On Behalf of the China Kadoorie Biobank Collaborative Group 2022Chinese Medical Journal2022,,6:17
3Velocity and pressure distributions in discharge tunnel of rotary-obstruction composite inner energy dissipation显示文摘On the basis of model test and theoretical analysis of velocity and pressure distributions,an hypothesis is presented that the distribution of tangential velocity in radial direction seems to be a combinational distribution of a quasi-free vortex and a quasi-forced vortex for the discharge tunnel of rotary-obstruction composite inner energy dissipation.The variations of corresponding parameters about the hypothesis are obtained under test conditions in this paper.The formula of pressure distribution in radial direction is deduced theoretically,and the theoretical values of pressure distribution computed by the formula are well consistent with the measured ones,showing that the formula is correct and can be applied to the computation and analysis of pressure distribution of this discharge tunnel.CAO ShuangLi 1,NIU ZhengMing 1,YANG Jian 2 & LU HongBo 1 1 Xi’an University of Technology,Xi’an 710048,China 2 China Water Resources Pearl River Planning,Surveying & Designing Co.Ltd,Guangzhou 510610,China 2011Science China(Technological Sciences)2011,54,S1:10
4Preparation and arc erosion properties of Ag/Ti_2SnC composites under electric arc discharging显示文摘New Ag/Ti_2 SnC(Ag/TSC) composites with uniform microstructure were prepared by powder metallurgy. The superior wettability between Ag and Ti_2 SnC was confirmed with a contact angle of 14°. Arc erosion properties of Ag/10 wt%Ti_2 SnC(Ag/10 TSC) and Ag/20 wt%Ti_2 SnC(Ag/20 TSC) contacts were investigated under 400 V/100 A/AC-3 and compared with Ag/CdO contact.The Ag/10 TSC contact exhibited comparable arc erosion property to Ag/CdO contact. The fine arc erosion resistance was attributed to the good wettability between Ti_2 SnC and Ag,the good heat-conducting property of Ag/10 TSC, and the slight decomposition of Ti_2 SnC that absorbed part of electric arc energy. The excessive Ti_2 SnC significantly decreased the thermal conducting property of the Ag/20 TSC composite, resulting in the severe heat accumulation that decomposed Ti_2 SnC and deteriorated arc erosion property. The oxidation behavior of Ti_2 SnC under high electric arc temperature was also studied and then an arc erosion mechanism was proposed to get a comprehensive understanding on the arc erosion property of Ag/TSC composites.Jianxiang DING Wubian TIAN Peigen ZHANG Min ZHANG Jian CHEN Yamei ZHANG Zhengming SUN 2019Journal of Advanced Ceramics2019,8,1:9
5Microsatellite polymorphisms of Sichuan golden monkeys显示文摘Previous study using protein electrophoresis shows no polymorphism in 44 nuclear loci of Sichuan golden monkey (Rhinopithecus roxellana), which limits our understandings of its population genetic patterns in the nuclear genome. In order to obtain sufficient information, we scanned 14 microsatellite loci in a sample of 32 individuals from its three major habitats (Minshan, Qinling and Shen-nongjia). A considerable amount of polymorphisms were detected. The average heterozygosities in the local populations were all above 0.5. The differentiations among local populations were significant. There was evidence of geneflow among subpopulations, but geneflow between Qinling and Shennongjia local populations was the weakest. Minshan and Qinling populations might have gone through recent bottlenecks. The estimation of the ratio of the effective population sizes among local populations was close to that from census sizes. Comparisons to available mitochondria data suggested that R. roxellana’s social structures played an important role in shaping its population genetic patterns. Our study showed that the polymorphism level of R. roxellana was no higher than other endangered species; therefore, measures should be taken to preserve genetic diversity of this species.PAN Deng LI Ying HU Hongxing MENG Shijie MEN Zhengming FU Yunxin ZHANG Yaping 2005Chinese Science Bulletin2005,50,24:7
6Effects of rotational speed and fill level on particle mixing in a stirred tank with different impellers显示文摘The particle mixing was studied in a cylindrical stirred tank with elliptical dished bottom by experiments and simulations.The impeller types used were double helical ribbon(HR) + bottom HR,pitched blade ribbon + bottom HR,inner and outer HR + bottom HR,and pitched blade ribbon + Pfaudler + bottom HR labeled as impellers Ⅰ to Ⅳ,respectively.The quantitative correlations among the rotational speed,fill level and power consumption for impeller Ⅰ and impeller Ⅱ were obtained by experiments to validate the discrete element method(DEM) simulations.The particle mixing at different operating conditions was simulated via DEM simulations to calculate the mixing index using the Lacey method,which is a statistical method to provide a mathematical understanding of the mixing state in a binary mixture.The simulation results reveal that as the rotational speed increases,the final mixing index increases,and as the fill level increases,the final mixing index decreases.At the same operating conditions,impeller Ⅲ is the optimal combination,which provides the highest mixing index at the same revolutions.Yuyun Bao Yu Lu Ziqi Cai Zhengming Gao 2018Chinese Journal of Chemical Engineering2018,26,6:7
7Quadrature-based moment methods for the population balance equation: An algorithm review显示文摘The dispersed phase in multiphase flows can be modeled by the population balance model(PBM). A typical population balance equation(PBE) contains terms for spatial transport, loss/growth and breakage/coalescence source terms. The equation is therefore quite complex and difficult to solve analytically or numerically. The quadrature-based moment methods(QBMMs) are a class of methods that solve the PBE by converting the transport equation of the number density function(NDF) into moment transport equations. The unknown source terms are closed by numerical quadrature. Over the years, many QBMMs have been developed for different problems, such as the quadrature method of moments(QMOM), direct quadrature method of moments(DQMOM),extended quadrature method of moments(EQMOM), conditional quadrature method of moments(CQMOM),extended conditional quadrature method of moments(ECQMOM) and hyperbolic quadrature method of moments(Hy QMOM). In this paper, we present a comprehensive algorithm review of these QBMMs. The mathematical equations for spatially homogeneous systems with first-order point processes and second-order point processes are derived in detail. The algorithms are further extended to the inhomogeneous system for multiphase flows, in which the computational fluid dynamics(CFD) can be coupled with the PBE. The physical limitations and the challenging numerical problems of these QBMMs are discussed. Possible solutions are also summarized.Dongyue Li Zhipeng Li Zhengming Gao 2019Chinese Journal of Chemical Engineering2019,27,3:7
8Changes in T lymphocyte subsets after severe traumatic brain injury显示文摘BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16–62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14–15 points), including 18 males and 12 females, aging 15–58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury. Informed consents were obtained from all the patients or their relatives. METHODS: ① The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at 1, 3, 7 and 14 days after injury in both groups. ② The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1–14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. ① Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77–3.26, P < 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06–2.24, P < 0.05), and generally recovered to the normal levels at 14 days (P > 0.05). ② Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, χ2=37.29, P < 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections.Yulu Miao Mingxia Zhang Yulin Nie Wan Zhao Bin Huang Zhengming Jiang Shaoxiong Yu Zhibin Huang Hongjin Fu 2007Neural Regeneration Research2007,2,2:7
9Discrete element method study of effects of the impeller configuration and operating conditions on particle mixing in a cylindrical mixer显示文摘We employed the discrete element method to study the effects of the impeller configuration(i.e.,blade diameter,inclination angle,and blade number),rotational speed,and fill level on the flow and mixing of particles in a cylindrical mixer equipped with flat and inclined blades.The coefficient of rolling friction,coefficient of static friction,and coefficient of restitution were experimentally determined before the simulation,and simulation results of the torque and surface particle distribution were validated in experiments,particularly when using a true Young's modulus in the discrete element method.The performance of the mixer was assessed using the Lacey mixing index.The input work per unit volume was used to represent the mixing efficiency.The circumferential velocity and axial diffusion coefficient of the particles were quantitatively analyzed to reveal the effect of particle flow on the mixing.It was found that the mixing performance and efficiency of a three-blade mixer are better than those of two-and four-blade mixers.For pitched blades,a three-fiat-blade mixer has better mixing performance than a three-45°-blade own-pumping or a three-45°-blade up-pumping mixer,but the mixing efficiency of the three-45°-blade up-pumping mixer is the best among these three mixers.As the rotational speed increases,the mixing performance improves but the mixing efficiency hardly changes.When the fill level is 0.4 times the cylinder diameter,the 160D two-flat-blade mixer has good mixing performance with high mixing efficiency.The circumferential velocity has the greatest effect on mixing performance for side-by-side initial loading.Yuyun Bao Tianchi Li Dengfei Wang Ziqi Cai Zhengming Gao 2020Particuology2020,18,2:6
10Slip casting and pressureless sintering of Ti3AlC2显示文摘Slip casting and subsequent pressureless sintering(PLS)allow the preparation of complex-shaped and large-sized Ti3AlC2 components for many potential applications.The behaviors of the suspensions,green compacts,and sintered samples of Ti3AlC2 were studied in this paper.The optimized condition of 1 wt%of arabic gum as dispersant at pH=10 results in a Ti3AlC2 suspension for slip casting Ti3AlC2 green compacts without macro defects or cracks.The sintering temperature and Al4C3 embedding powder are found to dominate the properties of the sintered Ti3AlC2 samples.The Ti3AlC2 sample sintered at 1450℃for 1.5 h with Al4C3 embedding powder reaches the best properties,namely 95.3%relative density,hardness of 4.18 GPa,thermal conductivity of 29.11W·m-1·K-1,and electrical resistivity of 0.39μΩ·m.The findings in this work may pave the way for the application of MAX phases with large size and complex shape.Yimin GONG Wubian TIAN Peigen ZHANG Jian CHEN Yamei ZHANG Zhengming SUN 2019Journal of Advanced Ceramics2019,8,3:6
11中国成人糖尿病、血糖与结直肠癌发病率:针对50万人的前瞻性研究显示文摘背景糖尿病可致结直肠癌(CRC)的发病风险升高。糖尿病病程和非糖尿病患者的血糖与CRC发病风险之间的相关性仍不清楚。方法2004至2008年前瞻性中国Kadoofe Biobank研究从10个不同地区纳入了512 713名受试者。在10年随访期间,在基线无癌症史的510 136名受试者中共记录有3 024例新发CRC病例(1 745例结肠癌,1 716例直肠癌)。应用Cox回归分析对糖尿病(入组前诊断或筛查发现的)或无糖尿病病史者随机血糖(RPG)水平与CRC发病相关性的校正风险比(HR)进行估计。结果基线时,共有5.8%的受试者患有糖尿病。糖尿病患者发生CRC的校正HR为1.18(95%可信区间1.04~1.33),且发生结肠癌与直肠癌的风险相当[1.19(1.01~1.39)比1.14(0.96~1135)]。这些患者发生CRC的HR随糖尿病病程的延长而下降(趋势P值为0.03)。在入组前无糖尿病的受试者中,其RPG水平与CRC发病呈正相关,基线RPG每升高1 mmol/L其发生CRC的校正HR为1.04(1.02~1.05),且发生结肠癌与直肠癌的风险亦相当[1.03(1.01~1.05)比1.04(1.02~1.06)]。在男性中,糖尿病和RPG与CRC发病风险的相关性高于女性,但其差异无统计学意义(异质性检验的P值分别为0.3和0.2)。讨论在中国成年人中,未诊断糖尿病者其糖尿病和升高的血糖水平与CRC发病风险升高相关。Yuanjie Pang Christiana Kartsonak yu Guo Yiping Chen Ling Yang Zheng Bian Fiona Bragg Iona Y Millwood Leijia Shen Songgen Zhou Jiben Liu Junshi Chen Liming Li Michael V Holmes Zhengming Ghen 霍永丰(译) 2019英国医学杂志中文版2019,22,1:6
12Settling behavior of non-spherical particles in power-law fluids:Experimental study and model development显示文摘Solid-particle settling occurs in many natural and industrial processes, such as in the transportation of drilling cuttings and fracturing proppant. Knowledge of the drag coefficient and settling velocity of cuttings and proppant is of significance to hydraulics design, wellbore cleanout, and fracture optimization. We conducted 553 tests to investigate the settling characteristics of spherical and non-spherical particles in power-law fluids. Three major particle shapes (spherical, cubic, and cylindrical) and eight different particle sphericities were used to simulate cuttings and proppant, and power-law fluids were applied to simulate drilling and fracturing fluids. Based on the data analysis, a new drag coefficient-particle Reynolds number correlation was developed to determine the drag coefficient in a power-law fluid for spherical and non-spherical particles. The drag coefficient increases as the sphericity decreases for the same particle Reynolds number. For a specific particle shape, the drag coefficient decreases as the particle Reynolds number increases, but the decreasing trend is reduced at high particle Reynolds number conditions. An explicit settling-velocity equation was proposed to calculate the settling velocity of spherical and non-spherical particles in power-law fluids by considering the effect of sphericity. A suitable range for the proposed model is 0.0001 < Re <200, 0.471 <φ< 1, and 0.505 < n < 1. An illustrative example is presented to show how to calculate the drag coefficient and settling velocity in power-law fluids with given particle and fluid properties.Zhengming Xu Xianzhi Song Gensheng Li Zhaoyu Pang Zhaopeng Zhu 2019Particuology2019,17,5:6
13Detection of infrared photons with a superconductor显示文摘A superconductor single photon detector based on NbN nanowire was fabricated using electron beam lithography (EBL) and reactive ion etching (RIE) for infrared photon detection. When biased well below its critical current at 4.2 K, NbN nanowire is very sensitive to the incident photons. Typical telecommunication photons with a wavelength of 1550 nm were detected by this detector. Data analysis indicates the repeating rate of the device with 200 nm NbN nanowire may be up to 100 MHz, and the quantum efficiency is about 0.01% when biased at 0.95Ic.ZHANG LaBao ZHONG YangYin KANG Lin CHEN Jian JI ZhengMing XU WeiWei CAO ChunHai 2009Chinese Science Bulletin2009,54,12:6
14Hydrodynamic Behavior of a Single Bubble Rising in Viscous Liquids显示文摘The rising behavior of single bubbles has been investigated in six systems with different viscosity and Morton number(Mo) from 3.21×10-11 to 163. Bubbles with maximum equivalent diameter of up to 16 mm were investigated. The bubble Reynolds number(Re) ranged from 0.02 to 1200 covering 3 regimes in which two func-tions are obtained relating the drag coefficient,CD,with Re and Mo. It has been found that in the high Reynolds number regime the drag coefficient increases until the Reynolds number of about 1200. The classic expression of Jamialahmadi(1994) is improved and extended to high viscosity liquids. A new relationship for the aspect ratio of deformed bubbles in terms of Re,the Etvs number and Mo,applicable to a wide range of system properties,espe-cially in high viscosity liquids,is also suggested.CAI Ziqi BAO Yuyun GAO Zhengming 2010Chinese Journal of Chemical Engineering2010,18,6:6
15Design System of the Two-step Gear Reducer on Case-based Reasoning显示文摘The design of the two-step gear reducer is a tedious and time-consuming process.For the purpose of improving the efficiency and intelligence of design process,case-based reasoning(CBR) technology was applied to the design of the two-step gear reducer.Firstly,the current design method for the two-step gear reducer was analyzed and the principle of CBR was described.Secondly,according to the characteristics of the reducer,three key technologies of CBR were studied and the corresponding methods were provided,which are as follows:(a) an object-oriented knowledge representation method,(b) a retrieval method combining the nearest neighbor with the induction indexing,and(c) a case adaptation algorithm combining the revision based on rule with artificial revision.Also,for the purpose of improving the credibility of case retrieval,a new method for determining the weights of characteristics and a similarity formula were presented,which is a combinatorial weighting method with the analytic hierarchy process(AHP) and roughness set theory.Lastly,according to the above analytic results,a design system of the two-step gear reducer on CBR was developed by VC++,UG and Access 2003.A new method for the design of the two-step gear reducer is provided in this study.If the foregoing developed system is applied to design the two-step gear reducer,design efficiency is improved,which enables the designer to release from the tedious design process of the gear reducer so as to put more efforts on innovative design.The study result fully reflects the feasibility and validity of CBR technology in the process of the design of the mechanical parts.JI Aimin HUANG Quansheng XU Huanmin CHEN Zhengming 2009Chinese Journal of Mechanical Engineering2009,22,5:6
16Synthesis,biological activities and 3D-QSAR studies of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety显示文摘A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development.Jingbo Liu Fengyun Li Yuanhong Wang Haoxuan Zhang Jingyue Dong Pengwei Sun Yuxin Li Zhengming Li 2019Chinese Chemical Letters2019,30,3:5
17Mass transfer in gas–liquid stirred reactor with various triple-impeller combinations显示文摘The gassed power demand and volumetric mass transfer coefficient(kLa) were investigated in a fully baffled,dished-base stirred vessel with a diameter of 0.30 m agitated by five triple-impeller combinations. Six types of impellers(six-half-elliptical-blade disk turbine(HEDT), four-wide-blade hydrofoil impeller(WH) pumping down(D) and pumping up(U), parabolic-blade disk turbine(PDT), and CBY narrow blade(N) and wide blade(W)) were used to form five combinations identified by PDT + 2CBYN, PDT + 2CBYW, PDT + 2WHD,HEDT + 2WHDand HEDT + 2WHU, respectively. The results show that the relative power demand of HEDT + 2WHUis higher than that of other four impeller combinations under all operating conditions. At low superficial gas velocity(uG), kLa differences among impeller combinations are not obvious. However,when uG is high, PDT + 2WHDshows the best mass transfer performance and HEDT + 2WHUshows the worst mass transfer performance under all operating conditions. At high uGand a given power input, the impeller combinations with high agitation speed and big projection cross-sectional area lead to relatively high values of kLa. Based on the experimental data, the regressed correlations of gassed power number with Froude number and gas flow number, and kLa with power consumption and superficial gas velocity are obtained for five different impeller combinations, which could be used as guidance for industrial design.Jinjin Zhang Zhengming Gao Yating Cai Ziqi Cai Jie Yang Yuyun Bao 2016Chinese Journal of Chemical Engineering2016,24,6:5
18DJ-1 is involved in the multidrug resistance of SGC7901 gastric cancer cells through PTEN/PI3K/Akt/Nrf2 pathway显示文摘Gastric cancer is a common malignancy worldwide.The occurrence of multidrug resistance(MDR)is the major obstacle for effective gastric cancer chemotherapy.In this study,the in-depth molec-ular mechanism of the DJ-1-induced MDR in SGC7901 gastric cancer cells was investigated.The results showed that DJ-1 expression level was higher in MDR variant SGC7901NCR cells than that in its parental SGC7901 cells.Moreover,DJ-1 overexpression conferred the MDR phenotype to SGC7901 cells,while DJ-1 knockdown in SGC7901NCR cells induced re-sensitization to adriamycin,vincristine,cisplatin,and 5-fluorouracil.These results suggested that DJ-1 mediated the develop-ment of MDR in SGC7901 gastric cancer cells.Importantly,further data revealed that the activation of PI3k/Akt and Nrf2 signaling pathway were required for the DJ-1-induced MDR phenotype in SGC7901 gastric cancer cells.Meanwhile,we found that Pl3k/Akt pathway was activated probably through DJ-1 directly binding to and negatively regulating PTEN,consequently resulting in Nrf2 phosphorylation and activation,and thereby inducing Nrf2-dependent P-glycoprotein(P-gp)and Bcl-2 expressions in the DJ-1-mediated MDR of SGC7901 gastric cancer cells.Overall,these results revealed that activating PTEN/PI3K/Akt/Nrf2 pathway and subsequently upregulating P-gp and Bcl-2 expression could be a critical mechanism by which DJ-1 mediates the development of MDR in SGC7901 gastric cancer cells.The new findings may be helpful for understanding the mechanisms of MDR in gastric cancer cells,prompting its further investigation as a molecular target to overcome MDR.Lejia Qiu Zhaoxia Ma Xiaoran Li Yizhang Deng Guangling Duan Le Zhao Xingwang Xu Lin Xiao Haoyue Liu Zhengming Zhu Heping Chen 2020Acta Biochimica et Biophysica Sinica2020,52,11:5
19Spontaneous Growth of Metal Whiskers on Surfaces of Solids:A Review显示文摘Spontaneous metal whisker growth phenomenon has been studied for^70 years,but still resists interpretations,which has haunted the electronics-rich systems from the birth of the industry since whiskers may lead to short circuits and hence other disasters.In addition to reliability problems,threat of Pb whiskers to human health is also significant due to the toxicity of the element and its geometry as well as its nanometer size.This issue becomes more attention drawing and urgent due to the restrictions on Pb use in EU,Japan etc.,which phases out the Pb-addition practice to mitigate Sn whiskers.This paper reviews the origin of the whiskering phenomenon and whisker-induced problems,ranging from early in the World War Ⅱ to the present;details the development of this issue in the electronics-rich systems including the phenomenon,problems and remedies;pictures the long history of the developments of the growth mechanisms and models which are full of hardship and contradictions.New aspects on the spontaneous whisker growth in some different substrates,such as in brasses and MAX phase materials are reviewed in more details.The latter was found to be a promising system to understand the whisker growth phenomenon,with new growth models proposed that may shed new light to the intricate battle field of the metal whisker research in general.Peigen Zhang Yamei Zhang Zhengming Sun 2015Journal of Materials Science & Technology2015,31,7:5
20Outage Probability Minimization for Low-Altitude UAV-Enabled Full-Duplex Mobile Relaying Systems显示文摘In this paper, a novel unmanned aerial vehicle(UAV)-enabled full duplex decode-and-forward(DF) technique is used in mobile relaying system. Compared with conventional static relaying, mobile relaying provides more degree of freedom for experiencing better channel conditions and further improving the system reliable performance. The source and relay transmit power as well as relay trajectory are jointly optimized for sum outage probability minimization in mobile relaying system. Due to the non-convex nature of the original problem, block coordinate decent optimization techniques are employed to decompose it into two sub-problems, which leads to an efficient iterative algorithm. Specifically, for the pre-determined relay trajectory, the optimal transmit power of source and relay are obtained by solving Karush-Kuhn-Tucker(KKT) conditions. For the given source/relay power allocation, the optimal UAV trajectory is obtained by solving dual problem. Based on the two steps, an iterative algorithm is proposed to jointly optimize source/relay power allocation and UAV trajectory alternately. Numerical results show the performance gain of our proposed scheme.Meng Hua Yi Wang Zhengming Zhang Chunguo Li Yongming Huang Luxi Yang 2018China Communications2018,15,5:5
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