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Global patterns of breast cancer incidence and mortality:A population-based cancer registry data analysis from 2000 to 2020 被引量:99
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作者 Shaoyuan Lei Rongshou Zheng +6 位作者 Siwei Zhang Shaoming Wang Ru Chen Kexin Sun Hongmei Zeng jiachen Zhou Wenqiang Wei 《Cancer Communications》 SCIE 2021年第11期1183-1194,共12页
Background:Breast cancer is the most commonly diagnosed cancer and leading cause of cancer death among women worldwide but has patterns and trends which vary in different countries.This study aimed to evaluate the glo... Background:Breast cancer is the most commonly diagnosed cancer and leading cause of cancer death among women worldwide but has patterns and trends which vary in different countries.This study aimed to evaluate the global patterns of breast cancer incidence and mortality and analyze its temporal trends for breast cancer prevention and control.Methods:Breast cancer incidence and mortality data in 2020 were obtained from the GLOBOCAN online database.Continued data from the Cancer Incidence in Five Continents Time Trends,the International Agency for Research on cancer mortality and China National Central Cancer Registry were used to analyze the time trends from 2000 to 2015 through Joinpoint regression,and annual average percent changes of breast cancer incidence and mortality were calculated.Association between Human Development Index and breast cancer incidence and mortality were estimated by linear regression.Results:There were approximately 2.3 million new breast cancer cases and 685,000 breast cancer deaths worldwide in 2020.Its incidence and mortality varied among countries,with the age-standardized incidence ranging from the highest of 112.3 per 100,000 population in Belgium to the lowest of 35.8 per 100,000 population in Iran,and the age-standardized mortality from the highest of 41.0 per 100,000 population in Fiji to the lowest of 6.4 per 100,000 population in South Korea.The peak age of breast cancer in some Asian and African countries were over 10 years earlier than in European or American countries.As for the trends of breast cancer,the age-standardized incidence rates significantly increased in China and South Korea but decreased in the United States of America(USA)during 2000-2012.Meanwhile,the age-standardized mortality rates significantly increased in China and South Korea but decreased in the United Kingdom,the USA,and Australia during 2000 and 2015.Conclusions:The global burden of breast cancer is rising fast and varies greatly among countries.The incidence and mortality rates of breast cancer incre 展开更多
关键词 Breast cancer MORTALITY PATTERNS INCIDENCE time trends cancer registry cancer trends
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Characteristics and applications of gas desorption with excavation disturbances in coal mining 被引量:31
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作者 jiachen Wang 《International Journal of Coal Science & Technology》 EI 2015年第1期30-37,共8页
According to the deficiency of experiment system for gas adsorption and desorption in coal mass, a large scale experiment system is developed independently by researchers. This experiment system is composed of primary... According to the deficiency of experiment system for gas adsorption and desorption in coal mass, a large scale experiment system is developed independently by researchers. This experiment system is composed of primary and auxiliary boxes, power transmission system, mining system, loading system, gas charging system, data monitoring and intelligent acquisition system. The maximum experiment coal consumption is 1200 kg, the mining system is developed to conduct experiment for gas desorption under excavating disturbance, and the plane-charging cribriform ventilation device is developed to realize uniform ventilation for experiment coal sample, which is accord with the actual gas source situation of coal bed. The desorption characteristics of gas in coal are experimentally studied under the conditions of nature and mining using the experiment system. The results show that, compare with nature condition, the permeability of coal and the velocity of gas desorption could significantly increase under the influence of coal pressure relief and destruction caused by mining, and the degree of gas desorption could somewhat increase too. Finally, pressure relief gas extraction of current seam and adjacent seams after mining in a certain coal mine of Yangquan mining area are introduced, and the gas desorption experiment results is verified by analyzing the effect of gas extraction. 展开更多
关键词 Gas adsorption and desorption experimental system MINING Gas desorption ~ Simultaneous extraction of coal and gas
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Initial identification of heavy metals contamination in Taihu Lake, a eutrophic lake in China 被引量:27
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作者 Xia Jiang Wenwen Wang +2 位作者 Shuhang Wang Bo Zhang jiachen Hu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第9期1539-1548,共10页
A detailed investigation of seven heavy metals (Cu, Cd, Cr, As, Pb, Zn, Ni) in the water column, interstitial water and surface sediment was conducted to quantify the extent of their contamination in Taihu Lake. Res... A detailed investigation of seven heavy metals (Cu, Cd, Cr, As, Pb, Zn, Ni) in the water column, interstitial water and surface sediment was conducted to quantify the extent of their contamination in Taihu Lake. Results showed the average total concentrations ranged from 0.93μg/L for Cd to 47.03 μg/L for Zn. The dissolved concentrations in the overlying water ranged from 0.06μg/L for Cd to 15.86 μg/L for Zn. The metals in the Taihu Lake surface water were primarily in the particulate phase, especially for Cd, whose particulate concentration represented 94.3% of the total. In the surface sediment, the mean concentrations for Cr, Ni, Cu, Zn, As, Cd and Pb were 41.50, 28.72, 27.82, 65.46, 5.94, 0.82 and 41.17 mg/kg, respectively. The metals in the water column and sediments of Taihu Lake displayed significant spatial variations, and the higher metal concentrations mainly occurred in the north and west of Taihu Lake, especially in Zhushan Bay and West Taihu Lake. A quality assessment indicated that most of the metals in the surface water of Taihu Lake had no or low adverse health effects on organisms, except for Pb and Cu, which may cause chronic toxicity. Compared with the "Consensus-Based Sediment Quality Guidelines", the polluting metals were Cr, Ni and Cd, and the polluted regions were confined to Zhnshan Bay, Meiliang Bay and the west of Taihu Lake, especially for north of Zhushan Bay. The polluted areas for Cr, Ni and Cd were 14.36, 34.70 and 13.24 km2, respectively. We suggest that Cr, Ni, and Cd in the polluted areas should be addressed and that tissue chemistry and sediment toxicity assessments be performed as soon as possible. 展开更多
关键词 Taihu Lake water SEDIMENT heavy metal ASSESSMENT
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Enhancement of human ACAT1 gene expression to promote the macrophage-derived foam cell formation by dexamethasone 被引量:25
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作者 LiYANG JinBoYANG +8 位作者 jiachen GuangYaoYU PeiZHOU LeiLEI ZhenZhenWANG CatherineCYCHANG XinYingYANG TaYuanCHANG BoLiangLI 《Cell Research》 SCIE CAS CSCD 2004年第4期315-323,共9页
In macrophages, the accumulation of cholesteryl esters synthesized by the activated acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT1) results in the foam cell formation, a hallmark of early atherosclerotic lesions... In macrophages, the accumulation of cholesteryl esters synthesized by the activated acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT1) results in the foam cell formation, a hallmark of early atherosclerotic lesions. In this study, with the treatment of a glucocorticoid hormone dexamethasone (Dex), lipid staining results clearly showed the large accumulation of lipid droplets containing cholesteryl esters in THP-1-derived macrophages exposed to lower concentration of the oxidized low-density lipoprotein (ox-LDL). More notably, when treated together with specific anti-ACAT inhibitors, the abundant cholesteryl ester accumulation was markedly diminished in THP-1-derived macrophages, confirming that ACAT is the key enzyme responsible for intracellular cholesteryl ester synthesis. RT-PCR and Western blot results indicated that Dex caused up-regulation of human ACAT1 expression at both the mRNA and protein levels in THP-1 and THP-1-derived macrophages. The luciferase activity assay demonstrated that Dex could enhance the activity of human ACAT1 gene P1 promoter, a major factor leading to the ACAT1 activation, in a cell-specific manner. Further experimental evidences showed that a glucocorticoid response element (GRE) located within human ACAT1 gene P1 promoter to response to the elevation of human ACAT1 gene expression by Dex could be functionally bound with glucocorticoid receptor (GR) proteins. These data supported the hypothesis that the clinical treatment with Dex, which increased the incidence of atherosclerosis, may in part due to enhancing the ACAT1 expression to promote the accumulation of cholesteryl esters during the macrophage-derived foam cell formation, an early stage of atherosclerosis. 展开更多
关键词 ACAT DEXAMETHASONE MACROPHAGE cholesteryl ester gene promoter.
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High porosity and low thermal conductivity high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2C 被引量:25
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作者 Heng Chen Huimin Xiang +4 位作者 Fu-Zhi Dai jiachen Liu Yiming Lei Jie Zhang Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第8期1700-1705,共6页
Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densificat... Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densification of porous structure at high temperatures.In order to overcome these obstacles,herein,porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C was prepared by a simple method combing in-situ reaction and partial sintering.Porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C possesses homogeneous microstructure with grain size in the range of 100–500 nm and pore size in the range of 0.2–1μm,which exhibits high porosity of 80.99%,high compressive strength of 3.45 MPa,low room temperature thermal conductivity of 0.39 W·m^-1K^-1,low thermal diffusivity of 0.74 mm^2·s^-1and good high temperature stability.The combination of these properties renders porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))Cpromising as light-weight ultrahigh temperature thermal insulation materials. 展开更多
关键词 Ultrahigh temperature CERAMICS (UHTCs) HIGH ENTROPY CERAMICS (Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C Thermal CONDUCTIVITY POROSITY
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Insulating materials for realising carbon neutrality:Opportunities,remaining issues and challenges 被引量:22
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作者 Chuanyang Li Yang Yang +25 位作者 Guoqiang Xu Yao Zhou Mengshuo Jia Shaolong Zhong Yu Gao Chanyeop Park Qiang Liu Yalin Wang Shakeel Akram Xiaoliang Zeng Yi Li Fangwei Liang Bin Cui Junpeng Fang Lingling Tang Yulin Zeng Xingtao Hu jiachen Gao Giovanni Mazzanti Jinliang He Jianxiao Wang Davide Fabiani Gilbert Teyssedre Yang Cao Feipeng Wang Yunlong Zi 《High Voltage》 SCIE EI 2022年第4期610-632,共23页
The 2050 carbon-neutral vision spawns a novel energy structure revolution,and the construction of the future energy structure is based on equipment innovation.Insulating material,as the core of electrical power equipm... The 2050 carbon-neutral vision spawns a novel energy structure revolution,and the construction of the future energy structure is based on equipment innovation.Insulating material,as the core of electrical power equipment and electrified transportation asset,faces unprecedented challenges and opportunities.The goal of carbon neutral and the urgent need for innovation in electric power equipment and electrification assets are first discussed.The engineering challenges constrained by the insulation system in future electric power equipment/devices and electrified transportation assets are investigated.Insulating materials,including intelligent insulating material,high thermal conductivity insulating material,high energy storage density insulating material,extreme environment resistant insulating material,and environmental-friendly insulating material,are cat-egorised with their scientific issues,opportunities and challenges under the goal of carbon neutrality being discussed.In the context of carbon neutrality,not only improves the understanding of the insulation problems from a macro level,that is,electrical power equipment and electrified transportation asset,but also offers opportunities,remaining issues and challenges from the insulating material level.It is hoped that this paper en-visions the challenges regarding design and reliability of insulations in electrical equipment and electric vehicles in the context of policies towards carbon neutrality rules.The authors also hope that this paper can be helpful in future development and research of novel insulating materials,which promote the realisation of the carbon-neutral vision. 展开更多
关键词 NEUTRAL INSULATION EXTREME
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High entropy(Yb0.25Y0.25Lu0.25Er0.25)2SiO5 with strong anisotropy in thermal expansion 被引量:21
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作者 Heng Chen Huimin Xiang +2 位作者 Fu-Zhi Dai jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第1期134-139,共6页
A novel high entropy(HE) rare earth monosilicate(Yb0.25Y0.25Lu0.25Er0.252 SiO5 was synthesized by solid-state reaction method.X-ray diffraction and scanning electron microscopy analysis indicate that a single solid so... A novel high entropy(HE) rare earth monosilicate(Yb0.25Y0.25Lu0.25Er0.252 SiO5 was synthesized by solid-state reaction method.X-ray diffraction and scanning electron microscopy analysis indicate that a single solid solution is formed with homogeneous distribution of rare-earth elements.HE(Yb0.25Y0.25Lu0.255 Er0.252 SiO5 exhibits excellent phase stability and anisotropy in thermal expansion.The coefficients of thermal expansion(CTEs) in three crystallographic directions are:αa=(2.57±0.07)×10^-6 K^-1,αb=(8.07±0.13)×10^-6 K^-1,αc=(9.98±0.10)×10^-6 K^-1.The strong anisotropy in thermal expansion is favorable in minimizing the coating/substrate mismatch if preferred orientation of HE(Yb0.25Y0.25Lu0.25Er0.252 SiO5 is controlled on either metal or ceramic substrate. 展开更多
关键词 HIGH ENTROPY ceramics RARE earth monosilicates SOLID-STATE reaction Thermal expansion ANISOTROPY
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High entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12:A novel high temperature stable thermal barrier material 被引量:21
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作者 Heng Chen Zifan Zhao +5 位作者 Huimin Xiang Fu-Zhi Dai Wei Xu Kuang Sun jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第13期57-62,共6页
Ytterbium aluminum garnet(Yb3Al5O12)is considered as a promising thermal barrier material.However,the main limitations of Yb3Al5O12 for thermal barrier applications are relative low thermal expansion coefficient and h... Ytterbium aluminum garnet(Yb3Al5O12)is considered as a promising thermal barrier material.However,the main limitations of Yb3Al5O12 for thermal barrier applications are relative low thermal expansion coefficient and high thermal conductivity.In order to overcome these obstacles,herein,a new high entropy(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic was designed,and then powders and bulk were prepared through solid-state reaction method and spark plasma sintering(SPS),respectively.The thermal expansion coefficient of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 is(8.54±0.29)×10^-6 K^-1 at 673 K–1273 K,which is about 9%higher than that of Yb3Al5O12.The thermal conductivity of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 ceramic is 3.81 W·m^-1 K^-1 at 300 K,which is about 18%lower than that of Yb3Al5O12.Moreover,there is no reaction between HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 and thermally grown(TG)Al2O3 even at 1600℃.After annealing at 1590℃for 18 h,the average grain size of HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 increases only from 1.56μm to 2.27μm.Close thermal expansion coefficient to TG Al2O3,low thermal conductivity,good phase stability,excellent chemical compatibility with TG Al2O3 and slow grain growth rate make HE(Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 promising for thermal barrier applications. 展开更多
关键词 High entropy ceramics (Y0.2Yb0.2Lu0.2Eu0.2Er0.2)3Al5O12 Thermal barrier coatings Thermal conductivity GARNET
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Porous high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2: A novel strategy towards making ultrahigh temperature ceramics thermal insulating 被引量:21
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作者 Heng Chen Huimin Xiang +2 位作者 Fu-Zhi Dai jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第10期2404-2408,共5页
Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity a... Transition metal diborides based ultrahigh temperature ceramics(UHTCs) are characterized by high melting point, high strength and hardness, and high electrical and thermal conductivity. The high thermal conductivity arises from both electronic and phonon contributions. Thus electronic and phonon contributions must be controlled simultaneously in reducing the thermal conductivity of transition metal diborides. In high entropy(HE) materials, both electrons and phonons are scattered such that the thermal conductivity can significantly be reduced, which opens a new window to design novel insulating materials. Inspired by the high entropy effect, porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is designed in this work as a new thermal insulting ultrahigh temperature material and is synthesized by an in-situ thermal borocarbon reduction/partial sintering process. The porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 possesses high porosity of 75.67%, pore size of 0.3–1.2 μm, homogeneous microstructure with small grain size of 400–800 nm, which results in low room temperature thermal diffusivity and thermal conductivity of 0.74 mm2 s^-1 and 0.51 W m^-1K^-1, respectively. In addition, it exhibits high compressive strength of3.93 MPa. The combination of these properties indicates that exploring porous high entropy ceramics such as porous HE(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 is a novel strategy in making UHTCs thermal insulating. 展开更多
关键词 High entropy ceramics (Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)B2 Transition metal diborides Porous materials Thermal insulating In-situ reaction/partial sintering
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Colorectal cancer burden and trends:Comparison between China and major burden countries in the world 被引量:21
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作者 jiachen Zhou Rongshou Zheng +8 位作者 Siwei Zhang Hongmei Zeng Shaoming Wang Ru Chen Kexin Sun Minjuan Li Jianhua Gu Guihua Zhuang Wenqiang Wei 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第1期1-10,共10页
Objective:To summarize the colorectal cancer(CRC)burden and trend in the world,and compare the difference of CRC burden between other countries and China.Methods:Incidence and mortality data were extracted from the GL... Objective:To summarize the colorectal cancer(CRC)burden and trend in the world,and compare the difference of CRC burden between other countries and China.Methods:Incidence and mortality data were extracted from the GLOBOCAN2018 and Cancer Incidence in Five Continents.Age-specific incidence trend was conducted by Joinpoint analysis and average annual percent changes were calculated.Results:About 1.85 million new cases and 0.88 million deaths were expected in 2018 worldwide,including 0.52 million(28.20%)new cases and 0.25 million(28.11%)deaths in China.Hungary had the highest age-standardized incidence and mortality rates in the world,while for China,the incidence and mortality rates were only half of that.CRC incidence and mortality were highly correlated with human development index(HDI).Unlike the rapid increase in Republic of Korea and the downward trend in Canada and Australia,the age-standardized incidence rates by world standard population in China and Norway were rising gradually.The age-specific incidence rate in the age group of 50-59 years in China was increasing rapidly,while in Republic of Korea and Canada,the fastest growing age group was 30-39 years.Conclusions:The variations of CRC burden reflect the difference of risk factors,as well as levels of HDI and screening(early detection activities).The burden of CRC in China is high,and the incidence of CRC continues to increase,which may lead to a sustained increase in the burden of CRC in China in the future.Screening should be expanded to control CRC,and focused on young people in China. 展开更多
关键词 Colorectal cancer BURDEN China TREND
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Single-shot lensless imaging with fresnel zone aperture and incoherent illumination 被引量:17
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作者 jiachen Wu Hua Zhang +3 位作者 Wenhui Zhang Guofan Jin Liangcai Cao George Barbastathis 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期1509-1519,共11页
Lensless imaging eliminates the need for geometric isomorphism between a scene and an image while allowing the construction of compact,lightweight imaging systems.However,a challenging inverse problem remains due to t... Lensless imaging eliminates the need for geometric isomorphism between a scene and an image while allowing the construction of compact,lightweight imaging systems.However,a challenging inverse problem remains due to the low reconstructed signal-to-noise ratio.Current implementations require multiple masks or multiple shots to denoise the reconstruction.We propose single-shot lensless imaging with a Fresnel zone aperture and incoherent illumination.By using the Fresnel zone aperture to encode the incoherent rays in wavefront-like form,the captured pattern has the same form as the inline hologram.Since conventional backpropagation reconstruction is troubled by the twin-image problem,we show that the compressive sensing algorithm is effective in removing this twin-image artifact due to the sparsity in natural scenes.The reconstruction with a significantly improved signal-to-noise ratio from a single-shot image promotes a camera architecture that is flat and reliable in its structure and free of the need for strict calibration. 展开更多
关键词 ILLUMINATION FRESNEL removing
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Achieving strong microwave absorption capability and wide absorption bandwidth through a combination of high entropy rare earth silicide carbides/rare earth oxides 被引量:17
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作者 Heng Chen Biao Zhao +4 位作者 Zifan Zhao Huimin Xiang Fu-Zhi Dai jiachen Liu Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第12期216-222,共7页
Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applica... Developing electromagnetic(EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applications of common EM absorbing materials are encumbered by poor high-temperature stability, poor oxidation resistance, narrow absorption bandwidth or high density. Herein, the strong EM absorption capability and wide efficient absorption bandwidth of high entropy ceramics are reported for the first time, which are designed by a combination of the novel high entropy(HE) rare earth silicide carbides/rare earth oxides(RE3 Si2 C2/RE2 O3). Three HE powders, i.e., HERSC-1(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2),HERSC-2 HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3) and HERSC-3(HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)3 Si2 C2/HE(Tm0.2 Y0.2 Dy0.2 Gd0.2 Tb0.2)2 O3), are synthesized. Although HERSC-1 exhibits a limited absorption effect(the minimum reflection loss(RLmin) is-11.6 d B at 3.4 mm) and a relatively narrow effective absorption bandwidth(EAB) of 1.7 GHz, the optimal absorption RLminvalue and EAB of HERSC-2 and HERSC-3 are-40.7 d B(at 2.9 mm), 3.4 GHz and-50.9 d B(at 2.0 mm), 4.5 GHz,respectively, demonstrating strong microwave absorption capability and wide absorption bandwidth.Considering the better stability, low density and strong EM absorption effect, HE ceramics are promising as a new type of EM absorbing materials. 展开更多
关键词 High entropy ceramics Rare earth silicide carbides Absorption materials Reflection loss Interfacial polarization
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4K-DMDNet:diffraction model-driven network for 4K computer-generated holography 被引量:13
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作者 Kexuan Liu jiachen Wu +1 位作者 Zehao He Liangcai Cao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第5期17-29,共13页
Deep learning offers a novel opportunity to achieve both high-quality and high-speed computer-generated holography(CGH).Current data-driven deep learning algorithms face the challenge that the labeled training dataset... Deep learning offers a novel opportunity to achieve both high-quality and high-speed computer-generated holography(CGH).Current data-driven deep learning algorithms face the challenge that the labeled training datasets limit the training performance and generalization.The model-driven deep learning introduces the diffraction model into the neural network.It eliminates the need for the labeled training dataset and has been extensively applied to hologram generation.However,the existing model-driven deep learning algorithms face the problem of insufficient constraints.In this study,we propose a model-driven neural network capable of high-fidelity 4K computer-generated hologram generation,called 4K Diffraction Model-driven Network(4K-DMDNet).The constraint of the reconstructed images in the frequency domain is strengthened.And a network structure that combines the residual method and sub-pixel convolution method is built,which effectively enhances the fitting ability of the network for inverse problems.The generalization of the 4K-DMDNet is demonstrated with binary,grayscale and 3D images.High-quality full-color optical reconstructions of the 4K holograms have been achieved at the wavelengths of 450 nm,520 nm,and 638 nm. 展开更多
关键词 computer-generated holography deep learning model-driven neural network sub-pixel convolution OVERSAMPLING
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Quantitative phase imaging through an ultra-thin lensless fiber endoscope 被引量:13
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作者 Jiawei Sun jiachen Wu +6 位作者 Song Wu Ruchi Goswami Salvatore Girardo Liangcai Cao Jochen Guck Nektarios Koukourakis Juergen W.Czarske 《Light(Science & Applications)》 SCIE EI CAS CSCD 2022年第8期1843-1852,共10页
Quantitative phase imaging(QPI)is a label-free technique providing both morphology and quantitative biophysical information in biomedicine.However,applying such a powerful technique to in vivo pathological diagnosis r... Quantitative phase imaging(QPI)is a label-free technique providing both morphology and quantitative biophysical information in biomedicine.However,applying such a powerful technique to in vivo pathological diagnosis remains challenging.Multi-core fiber bundles(MCFs)enable ultra-thin probes for in vivo imaging,but current MCF imaging techniques are limited to amplitude imaging modalities.We demonstrate a computational lensless microendoscope that uses an ultra-thin bare MCF to perform quantitative phase imaging with microscale lateral resolution and nanoscale axial sensitivity of the optical path length.The incident complex light field at the measurement side is precisely reconstructed from the far-field speckle pattern at the detection side,enabling digital refocusing in a multi-layer sample without any mechanical movement.The accuracy of the quantitative phase reconstruction is validated by imaging the phase target and hydrogel beads through the MCF.With the proposed imaging modality,three-dimensional imaging of human cancer cells is achieved through the ultra-thin fiber endoscope,promising widespread clinical applications. 展开更多
关键词 FIBER phase THIN
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Three-dimensional experimental study of loose top-coal drawing law for longwall top-coal caving mining technology 被引量:13
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作者 jiachen Wang Jinwang Zhang +1 位作者 Zhengyang Song Zhaolong Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第3期318-326,共9页
Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-c... Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-coal drawing test with shields and the controlled test without shields are performed in the condition without any boundary effect. Test results show that shields will cause reduction in drawing volume of coal in the LTCC mining. The deflection phenomenon of drawing body is also observed in the controlled test, which is verified that the deflection of drawing body is caused by shield. It is found that the deflection angle decreases with increasing caving height, with the maximum value of atailand the minimum value of 0. In addition, the formula to calculate the drawing volume is proposed subsequently.The deflection of drawing body is numerically simulated using particle flow code PFC3 Dand the proposed formula to calculate drawing volume in LTCC is also verified. 展开更多
关键词 Longwall top-coal caving(LTCC) Caving shield Three-dimensional(3D) physical model test Deflection of drawing body PFC3D
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Synthesis and catalytic performance of macroporous La1-xCexCoO3 perovskite oxide catalysts with high oxygen mobility for catalytic combustion of soot 被引量:13
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作者 jiachen Sun Zhen Zhao +5 位作者 Yazhao Li Xuehua Yu Linlin Zhao Jianmei Li Yuechang Wei Jian Liu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第6期584-593,共10页
The disordered macroporous-mesoporous La1-xCexCoO3 catalysts were prepared by complexcombustion method with ethylene glycol as complexing agent at relatively low calcination temperature.The samples were characterized ... The disordered macroporous-mesoporous La1-xCexCoO3 catalysts were prepared by complexcombustion method with ethylene glycol as complexing agent at relatively low calcination temperature.The samples were characterized by means of X-ray diffraction,N2 adsorption-ndash;desorption,Xray photoelectron spectroscopy,transmission electron microscopy,hydrogen temperature-programmed reduction and soot temperature-programmed reduction,and so on.The results show that the use of complexing agent and relatively low calcination temperature increase the specific surface area of the catalyst and have abundant pore structure.The Ce ions introduced into lattice of LaCoO3 mainly exist in the form of tetravalent.At the same time,Ce ions enhance the redox performance of the catalyst and the mobility of active oxygen species,which enhances the catalytic activity of the catalyst for soot combustion.The results of activity test show that La0.9Ce0.1CoO3 catalyst exhibits the highest activity in the absence of NO and NO2,and its T10,T50 and T90 are 371,444,and 497℃,respectively.At the same time,a possible reaction mechanism is proposed in this study based on the turnover frequency(TOF) calculated by isothermal anaerobic titrations,XPS and XRD results. 展开更多
关键词 Macroporous structure La1-xCexCoO3 perovskite oxide Reaction mechanism Soot combustion Rare earths
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Ribosomal proteins and human diseases:molecular mechanisms and targeted therapy 被引量:10
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作者 Jian Kang Natalie Brajanovski +3 位作者 Keefe T.Chan jiachen Xuan Richard B.Pearson Elaine Sanij 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第9期2748-2769,共22页
Ribosome biogenesis and protein synthesis are fundamental rate-limiting steps for cell growth and proliferation.The ribosomal proteins(RPs),comprising the structural parts of the ribosome,are essential for ribosome as... Ribosome biogenesis and protein synthesis are fundamental rate-limiting steps for cell growth and proliferation.The ribosomal proteins(RPs),comprising the structural parts of the ribosome,are essential for ribosome assembly and function.In addition to their canonical ribosomal functions,multiple RPs have extra-ribosomal functions including activation of p53-dependent or p53-independent pathways in response to stress,resulting in cell cycle arrest and apoptosis.Defects in ribosome biogenesis,translation,and the functions of individual RPs,including mutations in RPs have been linked to a diverse range of human congenital disorders termed ribosomopathies.Ribosomopathies are characterized by tissue-specific phenotypic abnormalities and higher cancer risk later in life.Recent discoveries of somatic mutations in RPs in multiple tumor types reinforce the connections between ribosomal defects and cancer.In this article,we review the most recent advances in understanding the molecular consequences of RP mutations and ribosomal defects in ribosomopathies and cancer.We particularly discuss the molecular basis of the transition from hypo-to hyper-proliferation in ribosomopathies with elevated cancer risk,a paradox termed"Dameshek's riddle."Furthermore,we review the current treatments for ribosomopathies and prospective therapies targeting ribosomal defects.We also highlight recent advances in ribosome stress-based cancer therapeutics.Importantly,insights into the mechanisms of resistance to therapies targeting ribosome biogenesis bring new perspectives into the molecular basis of cancer susceptibility in ribosomopathies and new clinical implications for cancer therapy. 展开更多
关键词 ELEVATED MECHANISMS consequences
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Signatures within esophageal microbiota with progression of esophageal squamous cell carcinoma 被引量:9
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作者 Minjuan Li Dantong Shao +4 位作者 jiachen Zhou Jianhua Gu Junjie Qin Wen Chen Wenqiang Wei 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第6期755-767,共13页
Objective: Esophageal squamous cell carcinoma(ESCC) is one of the dominant malignances worldwide, but currently there is less focus on the microbiota with ESCC and its precancerous lesions.Methods: Paired esophageal b... Objective: Esophageal squamous cell carcinoma(ESCC) is one of the dominant malignances worldwide, but currently there is less focus on the microbiota with ESCC and its precancerous lesions.Methods: Paired esophageal biopsy and swab specimens were obtained from 236 participants in Linzhou, China.Data from 16 S ribosomal RNA gene sequencing were processed using quantitative insights into microbial ecology(QIIME2) and R Studio to evaluate differences. The Wilcoxon rank sum test and Kruskal-Wallis rank sum test were used to compare diversity and characteristic genera by specimens and participant groups. Ordinal logistic regression model was used to build microbiol prediction model.Results: Microbial diversity was similar between biopsy and swab specimens, including operational taxonomic unit(OTU) numbers and Shannon index. There were variations and similarities of esophageal microbiota among different pathological characteristics of ESCC. Top 10 relative abundance genera in all groups include Streptococcus, Prevotella, Veillonella, Actinobacillus, Haemophilus, Neisseria, Alloprevotella, Rothia, Gemella and Porphyromonas. Genus Streptococcus, Haemophilus, Neisseria and Porphyromonas showed significantly difference in disease groups when compared to normal control, whereas Streptococcus showed an increasing tendency with the progression of ESCC and others showed a decreasing tendency. About models based on all combinations of characteristic genera, only taken Streptococcus and Neisseria into model, the prediction performance was the ideal one, of which the area under the curve(AUC) was 0.738.Conclusions: Esophageal biopsy and swab specimens could yield similar microbial characterization. The combination of Streptococcus and Neisseria has the potential to predict the progression of ESCC, which is needed to confirm by large-scale, prospective cohort studies. 展开更多
关键词 Esophageal squamous cell carcinoma precancerous lesions 16S rRNA STREPTOCOCCUS Neisseria
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Nanoscale multi-beam lithography of photonic crystals with ultrafast laser 被引量:8
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作者 Jiaqun Li Jianfeng Yan +3 位作者 Lan Jiang jiachen Yu Heng Guo Liangti Qu 《Light(Science & Applications)》 SCIE EI CSCD 2023年第8期1604-1615,共12页
Photonic crystals are utilized in many noteworthy applications like optical communications,light flow control,and quantum optics.Photonic crystal with nanoscale structure is important for the manipulation of light pro... Photonic crystals are utilized in many noteworthy applications like optical communications,light flow control,and quantum optics.Photonic crystal with nanoscale structure is important for the manipulation of light propagation in visible and near-infrared range.Herein,we propose a novel multi beam lithography method to fabricate photonic crystal with nanoscale structure without cracking.Using multi-beam ultrafast laser processing and etching,parallel channels with subwavelength gap are obtained in yttrium aluminum garnet crystal.Combining optical simulation based on Debye diffraction,we experimentally show the gap width of parallel channels can be controlled at nanoscale by changing phase holograms.With the superimposed phase hologram designing,functional structures of complicated channel arrays distribution can be created in crystal.Optical gratings of different periods are fabricated,which can diffract incident light in particular ways.This approach can efficiently manufacture nanostructures with controllable gap,and offer an alternative to the fabrication of complex photonic crystal for integrated photonics applications. 展开更多
关键词 LITHOGRAPHY BEAM OPTICS
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A Data-driven Method for Transient Stability Margin Prediction Based on Security Region 被引量:9
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作者 Jun An jiachen Yu +2 位作者 Zonghan Li Yibo Zhou Gang Mu 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2020年第6期1060-1069,共10页
Transient stability assessment(TSA)based on security region is of great significance to the security of power systems.In this paper,we propose a novel methodology for the assessment of online transient stability margi... Transient stability assessment(TSA)based on security region is of great significance to the security of power systems.In this paper,we propose a novel methodology for the assessment of online transient stability margin.Combined with a geographic information system(GIS)and transformation rules,the topology information and pre-fault power flow characteristics can be extracted by 2 D computer-vision-based power flow images(CVPFIs).Then,a convolutional neural network(CNN)-based comprehensive network is constructed to map the relationship between the steady-state power flow and the generator stability indices under the anticipated contingency set.The network consists of two components:the classification network classifies the input samples into the credibly stable/unstable and uncertain categories,and the prediction network is utilized to further predict the generator stability indices of the categorized samples,which improves the network ability to distinguish between the samples with similar characteristics.The proposed methodology can be used to quickly and quantitatively evaluate the transient stability margin of a power system,and the simulation results validate the effectiveness of the method. 展开更多
关键词 Security region computer-vision-based power flow image(CVPFI) transient stability margin convolutional neural network(CNN) comprehensive network
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