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1Epidemiology and risk factors of colorectal cancer in China显示文摘In China, colorectal cancer(CRC) ranked fourth and fifth in the highest incidence and mortality rates of all malignancies in 2018, respectively. Although these rates are below the world average, China placed first worldwide in the number of new CRC cases and CRC-related deaths because of its comparatively large population. This disease represents a threat to the health of population and incurs a heavy economic burden on the society and individuals. CRC has various risk factors, including age, sex, lifestyle, genetic factors, obesity, diabetes, gut microbiota status, and precancerous lesions. Furthermore, incidence and mortality rates of CRC are closely related to socioeconomic development levels, varying according to regional and population characteristics. Prevention is the main strategy to reduce incidence and mortality rates of CRC. This can be achieved through strategies stimulating lifestyle changes, healthy diet habits, and early screening for high-risk individuals. To reduce the burden of CRC, public health officials should promote prevention and management of modifiable risk factors through national policies. The rising incidence and mortality rates of CRC in China may be timely curbed by clarifying specific epidemiological characteristics, optimizing early screening strategies, and strictly implementing diagnosis and treatment guidelines. Thus, this study aimed to collect and report the current research status on epidemiology and risk factors of CRC in China.Yong Yang Zihan Han Xin Li An Huang Jingyi Shi Jin Gu 2020Chinese Journal of Cancer Research2020,32,6:42
2晚期非小细胞肺癌免疫检查点抑制剂新型生物标志物:血液PD-L1动态检测显示文摘背景免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)具有良好疗效已成为恶性肿瘤治疗领域备受瞩目的翘楚。然而,仅有小部分患者获得长期临床获益。如何选择生物标志物来筛查ICIs治疗优势人群仍是一大热点。方法收集51例晚期恶性肿瘤患者的肿瘤组织和配对血样本,进行PD-L1表达的相关性分析。40例晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)患者接受ICIs治疗,2个月时检测血液PD-L1(bloodPD-L1,bPD-L1)表达的动态变化,包括PD-L1 mRNA、外泌体PD-L1(exosomalPD-L1,exoPD-L1)蛋白和可溶性PD-L1(solublePD-L1,sPD-L1)。应用R软件计算最佳截断值,用于预测最佳客观缓解(best objective response,b OR)、无进展生存期(progression-free survival,PFS)和总生存期(overall survival,OS)。结果51例不同恶性肿瘤患者中,组织PD-L1(tissuePD-L1,tPD-L1)表达阳性患者的PD-L1mRNA表达水平显著升高。40例接受ICIs治疗的晚期NSCLC患者中,bPD-L1 mRNA上调≥2.04的患者b OR、PFS和OS更佳;21例接受ICIs治疗的晚期NSCLC患者中,exoPD-L1上调≥1.86的患者临床获益更大。sPD-L1动态变化与ICIs疗效无显著相关性。PD-L1 mRNA和exoPD-L1联合检测更有利于预测ICIs治疗疗效。结论bPD-L1表达与tPD-L1表达存在正相关;晚期NSCLC患者ICIs治疗初期PD-L1 mRNA和(或)exoPD-L1表达升高,可作为评估临床获益的新型生物标志物。Qiao YANG Mingjing CHEN Jiaoyang GU Kai NIU Xianlan ZHAO Linpeng ZHENG Zihan XU Yongxin YU Feng LI Lingxin MENG Zhengtang CHEN Wenlei ZHUO Luping ZHANG Jianguo SUN 杨峤(译) 孙建国(译) 2021中国肺癌杂志2021,24,12:10
3Cryo-EM structure of human mTOR complex 2显示文摘Xizi Chen Mengjie Liu Yuan Tian Jiabei Li Yilun Qi Dan Zhao Zihan Wu Min Huang Catherine C. L. Wong Hong-Wei Wang Jiawei Wang Huirong Yang Yanhui Xu 2018Cell Research2018,28,5:8
4Clinically relevant factors associated with quantitative optical coherence tomography angiography metrics in deep capillary plexus in patients with diabetes显示文摘Background:To test clinically relevant factors associated with quantitative artifact-free deep capillary plexus(DCP)metrics in patients with diabetes mellitus(DM).Methods:563 eligible eyes(221 with no diabetic retinopathy[DR],135 with mild DR,130 with moderate DR,and 77 with severe DR)from 334 subjects underwent optical coherence tomography-angiography(OCT-A)with a swept-source OCT(Triton DRI-OCT,Topcon,Inc.,Tokyo,Japan).Strict criteria were applied to exclude from analysis those DCP images with artifacts and of poor quality,including projection artifacts,motion artifacts,blurriness,signal loss,B-scan segmentation error,or low-quality score.A customized MATLAB program was then used to quantify DCP morphology from the artifact-free DCP images by calculating three metrics:foveal avascular zone(FAZ),vessel density(VD),and fractal dimension(FD).Results:166(29.5%)eyes were excluded after quality control,leaving in the analysis 397 eyes(170 with no DR,101 with mild DR,90 with moderate DR,36 with severe DR)from 250 subjects.In the multiple regression models,larger FAZ area was associated with more severe DR(β=0.687;p=0.037),shorter axial length(AL)(β=−0.171;p=0.003),thinner subfoveal choroid thickness(β=−0.122;p=0.031),and lower body mass index(BMI)(β=−0.090;p=0.047).Lower VD was associated with more severe DR(β=−0.842;p=0.001),shorter AL(β=0.107;p=0.039),and poorer visual acuity(VA)(β=−0.133;p=0.021).Lower FD was associated with more severe DR(β=−0.891;p<0.001)and with older age(β=−0.142;p=0.004).Conclusions:Quantitative artifact-free DCP metrics are associated with VA,DR severity,AL,subfoveal choroidal thickness,age,and BMI in diabetic patients.The effects of ocular and systemic factors should be considered for meaningful interpretations of DCP changes in DM patients.Fang Yao Tang Erica O.Chan Zihan Sun Raymond Wong Jerry Lok Simon Szeto Jason C.Chan Alexander Lam Clement C.Tham Danny S.Ng Carol Y.Cheung 2020Eye and Vision2020,7,1:7
5Architectural proteins for the formation and maintenance of the 3D genome显示文摘Eukaryotic genomes are densely packaged into hierarchical three-dimensional(3D) structures that contain information about gene regulation and many other biological processes. With the development of imaging and sequencing-based technologies, 3D genome studies have revealed that the high-order chromatin structure is composed of hierarchical levels, including chromosome territories, A/B compartments, topologically associated domains, and chromatin loops. However, how this chromatin architecture is formed and maintained is not completely clear. In this review, we introduce experimental methods to investigate the 3D genome, review major architectural proteins that regulate 3D chromatin organization in mammalian cells, such as CTCF(CCCTC-binding factor), cohesin, lamins, and transcription factors, and discuss relevant mechanisms such as phase separation.Mengfan Li Jingbo Gan Yuao Sun Zihan Xu Junsheng Yang Yujie Sun Cheng Li 2020Science China(Life Sciences)2020,63,6:7
6Trajectory clustering for arrival aircraft via new trajectory representation显示文摘Trajectory clustering can identify the flight patterns of the air traffic,which in turn contributes to the airspace planning,air traffic flow management,and flight time estimation.This paper presents a semantic-based trajectory clustering method for arrival aircraft via new proposed trajectory representation.The proposed method consists of four significant steps:representing the trajectories,grouping the trajectories based on the new representation,measuring the similarities between different trajectories through dynamic time warping(DTW)in each group,and clustering the trajectories based on k-means and densitybased spatial clustering of applications with noise(DBSCAN).We take the inbound trajectories toward Shanghai Pudong International Airport(ZSPD)to carry out the case studies.The corresponding results indicate that the proposed method could not only distinguish the particular flight patterns,but also improve the performance of flight time estimation.GUI Xuhao ZHANG Junfeng PENG Zihan 2021Journal of Systems Engineering and Electronics2021,32,2:5
7Evaluation of Chinese tea by the electronic nose and gas chromatography–mass spectrometry: Correlation with sensory properties and classification according to grade level显示文摘Zihan Qin Xueli Pang Dong Chen Huan Cheng Xiaosong Hu Jihong Wu 2013Food Research International2013,,:5
8Rational design of hierarchically porous Fe-N-doped carbon as efficient electrocatalyst for oxygen reduction reaction and Zn-air batteries显示文摘The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries.Zihan Meng Neng Chen Shichang Cai Jiawei Wu Rui Wang Tian Tian Haolin Tang 2021Nano Research2021,14,12:4
9Uplift mechanism for a shallow-buried structure in liquefi able sand subjected to seismic load: centrifuge model test and DEM modeling显示文摘Based on a centrifuge model test and distinct element method(DEM), this study provides new insights into the uplift response of a shallow-buried structure and the liquefaction mechanism for saturated sand around the structure under seismic action. In the centrifuge test, a high-speed microscopic camera was installed in the structure model, by which the movements of particles around the structure were monitored. Then, a two-dimensional digital image processing technology was used to analyze the microstructure of saturated sand during the shaking event. Herein, a numerical simulation of the centrifuge experiment was conducted using a two-phase(solid and fl uid) fully coupled distinct element code. This code incorporates a particle-fl uid coupling model by means of a 'fi xed coarse-grid' fl uid scheme in PFC3D(Particle Flow Code in Three Dimensions), with the modeling parameters partially calibrated based on earlier studies. The physical and numerical models both indicate the uplifts of the shallow-buried structure and the sharp rise in excess pore pressure. The corresponding micro-scale responses and explanations are provided. Overall, the uplift response of an underground structure and the occurrence of liquefaction in saturated sand are predicted successfully by DEM modeling. However, the dynamic responses during the shaking cannot be modeled accurately due to the restricted computer power.Zhou Jian Wang Zihan Chen Xiaoliang Zhang Jiao 2014Earthquake Engineering and Engineering Vibration2014,13,2:4
10Generation-expansion planning with linearized primary frequency response constraints显示文摘As renewable energy resources increasingly penetrate the electric grid,the inertia capability of power systems has become a developmental bottleneck.Nevertheless,the importance of primary frequency response(PFR)when making generation-expansion plans has been largely ignored.In this paper,we propose an optimal generation-expansion planning framework for wind and thermal power plants that takes PFR into account.The model is based on the frequency equivalent model.It includes investment,startup/shutdown,and typical operating costs for both thermal and renewable generators.The linearization constraints of PFR are derived theoretically.Case studies based on the modified IEEE 39-bus system demonstrate the efficiency and effectiveness of the proposed method.Compared with methods that ignore PFR,the method proposed in this paper can effectively reduce the cost of the entire planning and operation cycle,improving the accommodation rate of renewable energy.Zihan Wang Jianxiao Wang Gengyin Li Ming Zhou 2020Global Energy Interconnection2020,3,4:4
11Searching for the Nano-Hertz Stochastic Gravitational Wave Background with the Chinese Pulsar Timing Array Data ReleaseⅠ显示文摘Observing and timing a group of millisecond pulsars with high rotational stability enables the direct detection of gravitational waves(GWs).The GW signals can be identified from the spatial correlations encoded in the times-of-arrival of widely spaced pulsar-pairs.The Chinese Pulsar Timing Array(CPTA)is a collaboration aiming at the direct GW detection with observations carried out using Chinese radio telescopes.This short article serves as a“table of contents”for a forthcoming series of papers related to the CPTA Data Release 1(CPTA DR1)which uses observations from the Five-hundred-meter Aperture Spherical radio Telescope.Here,after summarizing the time span and accuracy of CPTA DR1,we report the key results of our statistical inference finding a correlated signal with amplitude logA_(c)=-14.4_(-2.8)^(+1.0)for spectral index in the range ofα∈[-1.8,1.5]assuming a GW background(GWB)induced quadrupolar correlation.The search for the Hellings–Downs(HD)correlation curve is also presented,where some evidence for the HD correlation has been found that a 4.6σstatistical significance is achieved using the discrete frequency method around the frequency of 14 n Hz.We expect that the future International Pulsar Timing Array data analysis and the next CPTA data release will be more sensitive to the n Hz GWB,which could verify the current results.Heng Xu Siyuan Chen Yanjun Guo Jinchen Jiang Bojun Wang Jiangwei Xu Zihan Xue RNicolas Caballero Jianping Yuan Yonghua Xu Jingbo Wang Longfei Hao Jingtao Luo Kejia Lee Jinlin Han Peng Jiang Zhiqiang Shen Min Wang Na Wang Renxin Xu Xiangping Wu Richard Manchester Lei Qian Xin Guan Menglin Huang Chun Sun Yan Zhu 2023Research in Astronomy and Astrophysics2023,23,7:3
12Adjusting energy level alignment between HTL and CsPbI_(2)Br to improve solar cell efficiency显示文摘Lead halide perovskites are at the forefront of optoelectronic materials due to their high absorption coefficient,tunable bandgap,long carrier diffusion length,and small exciton binding energy[1−3],yielding high-performance optoelectronic devices.Zihan Zhang Jia Li Zhimin Fang Haipeng Xie Yongbo Yuan Chuantian Zuo Liming Ding Bin Yang 2021Journal of Semiconductors2021,42,3:3
13A polypropylene melt-blown strategy for the facile and efficient membrane separation of oil-water mixtures显示文摘Porous materials with selective wettability and permeability have significant importance in oil-water separation,but complex fabrication processes are typically required to obtain the desired structures with suitable surface chemistry.In this work,an industrial melt-blown strategy that utilized commercially available polypropylene(PP)was used for the large-scale fabrication of superhydrophobic/superoleophilic membranes with staggered fabric structures.These membranes could readily separate different oils including pump oil and crude oil from various aqueous solutions such as strongly acidic,alkaline,and saline media.In addition,the separation efficiencies of these membranes exceeded 99%,and they could remain functional even after exposure to corrosive media.We anticipate that this work will further the design of membranes and enhance their applicability in oil-water separation,and provide researchers and engineers with a more effective tool for performing challenging separations and mitigating pollution.Zhenqiang Zhang Danfeng Yu Xiubin Xu Huayi Li Taoyan Mao Cheng Zheng Jianjia Huang Hui Yang Zihan Niu Xu Wu 2021Chinese Journal of Chemical Engineering2021,34,1:3
14PD-L1:expression regulation显示文摘Programmed death-ligand 1(PD-L1),expressed on the surface of tumor cells,can bind to programmed cell death-1(PD-1)on T cells.The interaction of PD-1 and PD-L1 can inhibit T-cell responses by decreasing T-cell activity and accelerating their apoptosis.Various cancers express high levels of PD-L1 and exploit PD-L1/PD-1 signaling to evade T-cell immunity,and immunotherapies targeting the PD-1/PD-L1 axis have been shown to exert remarkable anti-tumor effects;however,not all tumor patients benefit from these therapies.Therefore,study of the mechanisms regulating PD-L1 expression are imperative.In this review,we explore regulation of PD-L1 expression in the contexts of gene transcription,signaling pathways,histone modification and remodeling,microRNAs,long noncoding RNAs,and post-translational modification.Current developments in studies of agents that block PD-L1 and correlations between immunotherapies targeting PD-1/PD-L1 and PD-L1 expression are also summarized.Our review will assist in understanding of PD-L1 expression regulation and discusses the implications of reported findings in cancer diagnosis and immunotherapy.Yu-Jie Zhou Guoli Li Jiyin Wang Mengyuan Liu Zihan Wang Yu Song Xulong Zhang Xi Wang 2023Blood Science2023,5,2:3
15Large piezoelectric response in a family of metal-free perovskite ferroelectric compounds from first-principles calculations显示文摘Metal-free organic perovskite ferroelectric materials have been shown recently to have a number of attractive properties,including high spontaneous polarization and piezoelectric coefficients.In particular,slow evaporation of solutions containing organic amines,inorganic ammoniums,and dilute hydrohalogen acid has been shown to produce several attractive materials in the MDABCO-NH_(4)-I_(3) family(MDABCO is N-methyl-N’-diazabicyclo[2,2,2]octonium).In the present work,we study by first-principles calculations the origin of polarizaiton,electronic density of state,piezoelectric response,and elastic properties of MDABCO-NH_(4)-X_(3)(X=Cl,Br,I).We find that the dipole moments of the MDABCO and NH_(4) groups are negligible,and the large spontaneous polarization of MDABCONH_(4)-I_(3) mainly results from MDABCO and NH_(4) being off-center relative to I ions.Although the piezoelectric response of organic materials is usually very weak,we observe large piezoelectric strain components,d_(x4) and d_(x5);the calculated d_(x5) is 119 pC/N for MDABCO-NH_(4)-Cl_(3),248 pC/N for MDABCO-NH_(4)-Br_(3) and 178 pC/N for MDABCO-NH_(4)-I_(3).The large value of dx5 is found to be closely related with the large value of elastic compliance tensor,s44.These results show that MDABCO-NH_(4)-X_(3) metal-free organic perovskites have large piezoelectric response with soft elastic properties.Hui Wang Huihui Liu Zeyu Zhang Zihan Liu Zhenlong Lv Tongwei Li Weiwei Ju Haisheng Li Xiaowu Cai Han Han 2019npj Computational Materials2019,,1:3
16A highly active VOx-MnOx/CeO_(2) for selective catalytic reduction of NO:The balance between redox property and surface acidity显示文摘Excellent catalysts with low-temperature activity and relatively wide temperature window for selective catalytic reduction of NO with ammonia(NH_(3)-SCR) are highly demanded in view of the practical treatment of NO.Herein,we have designed a highly active VOx-MnOx/CeO_(2) material based on the intrinsic requirement of SCR reaction for catalyst,namely redox sites and surface acid sites.The vanadium oxide and manganese oxide are highly dispersed over the ceria mesosphere via simple incipient wetness impregnation.The loading of manganese could introduce acid sites and enhance the redox property remarkably,while the loading of vanadium increases acid sites and weakens redox property.Through tentatively controlling the appropriate loading ratio of the two components,the optimal catalyst achieves a balance between redox property and surface acidity.The work shed light on the development of new SCR catalyst with superior low temperature activity,wide work temperature window and good hydrothermal stability.Runnong Yang Zihan Gao Ming Sun Guangying Fu Gao Cheng Wuyuan Liu Xiaobo Yang Xiangyun Zhao Lin Yu 2021Journal of Rare Earths2021,39,11:3
17MARVEL:Multi-Agent Reinforcement Learning for VANET Delay Minimization显示文摘In urban Vehicular Ad hoc Networks(VANETs),high mobility of vehicular environment and frequently changed network topology call for a low delay end-to-end routing algorithm.In this paper,we propose a Multi-Agent Reinforcement Learning(MARL)based decentralized routing scheme,where the inherent similarity between the routing problem in VANET and the MARL problem is exploited.The proposed routing scheme models the interaction between vehicles and the environment as a multi-agent problem in which each vehicle autonomously establishes the communication channel with a neighbor device regardless of the global information.Simulation performed in the 3GPP Manhattan mobility model demonstrates that our proposed decentralized routing algorithm achieves less than 45.8 ms average latency and high stability of 0.05%averaging failure rate with varying vehicle capacities.Chengyue Lu Zihan Wang Wenbo Ding Gang Li Sicong Liu Ling Cheng 2021China Communications2021,18,6:2
18A Two-plume Convective Model for Precipitation Extremes显示文摘In the study of diagnosing climate simulations and understanding the dynamics of precipitation extremes,it is an essential step to adopt a simple model to relate water vapor condensation and precipitation,which occur at cloudmicrophysical and convective scales,to large-scale variables.Several simple models have been proposed;however,improvement is still needed in both their accuracy and/or the physical basis.Here,we propose a two-plume convective model that takes into account the subgrid inhomogeneity of precipitation extremes.The convective model has three components,i.e.,cloud condensation,rain evaporation,and environmental descent,and is built upon the zero-buoyancy approximation and guidance from the high-resolution reanalysis.Evaluated against the CMIP5 climate simulations,the convective model shows large improvements in reproducing precipitation extremes compared to previously proposed models.Thus,the two-plume convective model better captures the main physical processes and serves as a useful diagnostic tool for precipitation extremes.Zihan YIN Panxi DAI Ji NIE 2021Advances in Atmospheric Sciences2021,38,6:2
19AGRICULTURAL GREEN DEVELOPMENT TO ACHIEVE FOOD SECURITY AND CARBON REDUCTION IN THE CONTEXT OF CHINA'S DUAL CARBON GOALS显示文摘The agricultural sector,a major source of greenhouse gas emissions,and emissions from agriculture must be reduced substantially to achieve carbon(C)neutrality.Based on a literature analysis and other research results,this study investigated the effects and prospects of C reduction in agricultural systems under different scenarios(i.e.,methods and approaches)in the context of China's dual C goals,as those working in the agricultural sector have yet to reach a consensus on how to move forward.Different views,standards,and countermeasures were analyzed to provide a reference for agricultural action supporting China's C neutrality goal.Yulong YIN Kai HE Zhong CHEN Yangyang LI Fengling REN Zihan WANG Yingcheng WANG Haiqing GONG Qichao ZHU Jianbo SHEN Xuejun LIU Zhenling CUI 2023Frontiers of Agricultural Science and Engineering2023,10,2:2
20A green method for synthesizing novel nanoparticles and their application in flexible conductive patterns显示文摘A general and unified approach to synthesize Ag,Cu and Au nanoparticles(NPs)is developed at room temperature in air atmosphere under ultrasonication in poly(N-vinylpyrrolidone)(PVP)solutions with ascorbic acid and glucose as the reducing and nucleation agents,respectively.XRD,TEM,and HR-TEM analysis of the Ag,Cu,and Au NPs confirm purity and average diameters of 15.5±2.0 nm,50±3.0 nm,and 10±1.0 nm,respectively.An ultrasonic-assisted mechanism,wherein reduction occurs readily and produces anti-oxidation particles,is proposed and discussed.Fast infrared sintering was used to avoid damaging the substrate of conductive patterns whose resistivity at 10 W(~50℃)sintering power for less than 6 min reached up to 10±0.5 μΩ cm,40±3.0 μΩ cm,and 280±5 μΩ cm for Ag,Cu,and Au patterns,respectively.Paper-based electrodes were produced successfully and exhibited excellent flexibility and good conductivity.The potential of this method for large scale production is discussed.Wei Li Qiongying Cen Wenjiang Li Zihan Zhao Wenlong Yang Yuqian Li Minfang Chen Guang Yang Jinjun Yang 2020Journal of Materiomics2020,6,2:2
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