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Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan Xiu-Fang li Meng-Ya guo Mei Chen Ming Lv Rui li Zhi-ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

Impacts of climate change on ecosystem in Priority Areas of Biodiversity Conservation in China

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Chinese Science Bulletin 2014年第34期59卷 4668-4680页

作者： Xiaopu Wu Xin lin Yuan Zhang Junjing Gao li guo Junsheng li State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Academy of Environmental Sciences College of Water Sciences Beijing Normal University Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University

Priority Areas of Biodiversity Conservation(PABCs) are the key areas for future biodiversity conservation in China. In this study, we used 5 dynamic global vegetation models(DGVMs) to simulate the ecosystem function changes under future climate change scenario in the 32 terrestrial PABCs. We selected vegetation coverage,vegetation productivity, and ecosystem carbon balance as the indicators to describe the ecosystem function *** results indicate that woody vegetation coverage will greatly increase in the Loess Plateau Region, the North China Plain, and the Lower Hilly Region of South *** future climate change will have great impact on the original vegetation in alpine meadow and arid and semiarid regions. The vegetation productivity of most PABCs will enhance in the coming 100 years. The largest increment will take place in the southwestern regions with high elevation. The PABCs in the Desert Region of InnerMongolia-Xinjiang Plateau are with fastest productivity climbing, and these areas are also with more carbon sink accumulation in the future. DGVM will be a new efficient tool for evaluating ecosystem function changes in future in large scale. This study is expected to provide technical support for the future ecosystem management and biodiversity conservation under climate change.

关键词：生物多样性保护生态系统功能未来气候变化中国北方植被生产力黄土高原区植被覆盖率半干旱地区

Cytochrome P450 family 17 subfamily A member 1 mutation causes severe pseudohermaphroditism: A case report

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World Journal of Clinical Cases 2022年第11期10卷 3553-3560页

作者： Yu Gong Fang qin Wen-Jia li Le-Yu li Ping He Xing-Jian Zhou Department of Endocrine and Metabolism Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND 17α-Hydroxylase deficiency(17-OHD)is a rare form of congenital adrenal hyperplasia,characterized by hypertension,hypokalemia,and gonadal ***,due to the lack of a comprehensive understanding of this disease,it is prone to misdiagnosis and missed diagnosis,and there is no complete *** SUMMARY We report a female patient with *** patient was admitted to the Department of Neurology of our hospital due to limb *** treatment,it was found that the patient’s condition was difficult to correct except for hypokalemia,and her blood pressure was difficult to control with various antihypertensive *** was then transferred to our department for further *** physical examination,the patient's gonadal development was found to be abnormal,and chromosome analysis demonstrated karyotype 46,*** the possibility of 17-OHD,the cytochrome P450 family 17 subfamily A member 1(CYP17A1)test was performed to confirm the *** The clinical manifestations of 17-OHD are *** determination,imaging examination,chromosome determination and CYP17A1 gene test are helpful for early diagnosis.

关键词： Congenital adrenal cortex hyperplasia Cytochrome P450 family 17 subfamily A member 1 17α-Hydroxylase deficiency Pseudohermaphroditism Case report

Progress in corrosion-resistant coatings on surface of low alloy steel

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Journal of Iron and Steel Research International 2023年第2期30卷 193-215页

作者： Bao-sheng liu Jia-li li Wen-jie guo Peng-fei Xu Shao-hua Zhang Yue-zhong Zhang College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina

Low alloy steels are widely used in bridges,construction,chemical and various equipment and metal components due to their low cost and excellent mechanical *** in the literature related to the preparation,advantages and disadvantages,and applications along with research progress of various types of protective coatings suitable for low-alloy steel surfaces is reviewed,while a conclusive and comparative analysis is also afforded to the numerous factors influencing the protective ability of *** characteristics of coatings drawn from the latest published literature are discussed and suggest that the modification of traditional metal coatings and the development of new organic coatings under the consideration of environmental protection,low cost,simplicity and large-scale industrial application are simultaneously proceeding,which holds promise for improving the understanding of corrosion protection in related fields and helps to address some of the limitations identified with more conventional coating techniques.

关键词： Low alloy steel Corrosion-resistant coating Metal coating Composite coating Diffusion coating Organic coating

Influence of the ZSM-5 Support Acidity on the Catalytic Performance of Pd/ZSM-5 in Lean Methane Oxidation

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Chemical Research in Chinese Universities 2022年第1期38卷 229-236页

作者： LUO li WANG Sen WU Zhiwei qin Zhangfeng DONG Mei WANG Jianguo FAN Weibin State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001P.R.China University of the Chinese Academy of Sciences Beijing 100049P.R.China

Although zeolites are characterized by their special acidic properties, there is still no clear consensus on the effect of zeolite support acidity on the catalytic activity of supported Pd catalyst in methane oxidation. Herein, a series of Pd/H-ZSM-5 and Pd/Silicalite-1 catalysts was prepared by the deposition-precipitation method and used in lean methane oxidation. The effect of ZSM-5 support acidity on the catalytic performance of Pd/ZSM-5 was investigated. The results indicate that with the decrease of Si/Al ratio(x), viz., the increase of acid sites in H-ZSM-5(x), the catalytic activity of Pd/H-ZSM-5(x) increases substantially;the activity of various catalysts in the lean methane oxidation decreases in the order of Pd/H-ZSM-5(28)>Pd/H-ZSM-5(48)>Pd/H-ZSM-5(88)>Pd/H-ZSM-5(204)>Pd/Silicalite-1. Furthermore, various characterization measures reveal that the catalytic activity of Pd/H-ZSM-5(x) in lean methane oxidation is mainly related to the Lewis acid sites in the H-ZSM-5 support, whereas less relevant to the Brønsted acid sites. The abundant Lewis acid sites in H-ZSM-5 are capable to enhance the interaction between the Pd species and H-ZSM-5 support, which can inhibit the agglomeration of Pd particles and improve the dispersion of Pd species, and thus boost the catalytic activity of Pd/H-ZSM-5 in methane oxidation.

关键词： Lean methane Catalytic oxidation Pd/H-ZSM-5 Brønsted acid Lewis acid Pd dispersion

Ergochaeglobosins A—E, Unprecedented Heterodimers of Cytochalasan and Ergosterol from Chaeglobosin globosum P2-2-2

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Chinese Journal of Chemistry 2022年第16期40卷 1909-1916页

作者： Xiaogang Peng Junjun liu Chunlun qin Qian Wu Wanpeng li Fatemeh Mohammadipanah Hanli Ruan School of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyHubei Key Laboratory of Natural Medicinal Chemistry and Resource EvaluationWuhanHubei430030 China Pharmaceutical Biotechnology Lab School of Biology and Center of Excellence in Phylogeny of Living OrganismsCollege of ScienceUniversity of Tehran14155-6455TehranIran

Five novel heterodimers of cytochalasan and ergosterol,ergochaeglobosins A—E,were isolated from an endophytic fungus Chaetomium globosum *** A(1) possesses an unprecedented 5/6/13/6/5/6/6/6 fused octacyclic ring system,and ergochaeglobosins B(2) and C(3) form a unique 5/6/13/6/6/6/6/5 fused octacyclic ring system,whereas ergochaeglobosins D(4) and F(5) are the first cytochalasan heterodimers formed via a N-1′/C-3′′single *** structures with absolute configurations were established by extensive spectroscopic analyses,single-crystal X-ray diffraction,and ECD *** plausible biogenetic pathway of 1—5 was *** 1 exhibited inhibitory effects against ConA-induced T cells and LPS-induced B cells proliferation with IC50 values of 19.2 and 14.1μmol/L,***-treatment of 3(20μmol/L)with TRAIL(150 ng/mL)could significantly decrease the cell viability of A549 by 24.9%comparing with monotherapy of 3(20μmol/L).

关键词： Cytochalasan heterodimers Natural products Biological activity Chaeglobosin globosum P2-2-2 Structure elucidation

Regression analysis and its application to oil and gas exploration:A case study of hydrocarbon loss recovery and porosity prediction,China

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 240-252页

作者： Yang li Xiaoguang li Mingyu guo Chang Chen Pengbo Ni Zijian Huang liaohe Oilfield CNPCPanjinLiaoning124010China Tianjin Company of China National Offshore Oil Corporation Tianjin300452China China-France Bohai Geoservices Co. Ltd.Tianjin300450China Panjin Zhonglu Oil and Gas Technology Service Co. Ltd.PanjinLiaoning124000China

In oil and gas exploration,elucidating the complex interdependencies among geological variables is *** study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical *** a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological *** linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct *** Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of *** Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and *** the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative *** Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk *** Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend *** analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring it

关键词： Regression analysis Oil and gas exploration Multiple linear regression model Nonlinear regression model Hydrocarbon loss recovery Porosity prediction

Co_(78)Si_(8)B_(14)metallic glass:A highly efficient and ultra-sustainable Fenton-like catalyst in degrading wastewater under universal pH conditions

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Journal of Materials Science & Technology 2022年第18期113卷 105-116页

作者： Xindong qin Jiliang Xu Zhengwang Zhu Zhengkun li Dawei Fang Huameng Fu Shiming Zhang Haifeng Zhang Institute of Rare and Scattered Elements College of ChemistryLiaoning UniversityShenyang 110036China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao 266232China

Overcoming the pH limitation and increasing the catalyst reusability remain pressing demands for metal-lic glass(MG)in wastewater ***,Co_(78)Si_(8)B_(14)MG ribbons are used to degrade dye wastew-ater by activating hydrogen peroxide(H_(2)O_(2))as Fenton-like *** Co-based MG catalysts exhibit high degradation efficiency under both acidic and alkaline conditions,and the kinetic reaction rate at pH 10(0.176 min^(−1)) and pH 4(0.089 min^(−1)) is 5.9 and 1.2 times higher than that of the extensively studied Fe-based MG catalysts,***,the Co-based MG catalysts can be reused up to 20-60 times at universal pH conditions,demonstrating fairly good *** newly discovered Co-based MG catalysts do not follow the classical Fenton reactions with H_(2)O^(2) the way Fe-based MGs *** an acid environment,hydroxyl radicals play a dominant role in the degradation,while in an alkaline environ-ment,the effect of hydroxyl radicals is weakened,and Co^(3+) ions exert a relatively major function on the *** excellent performance in catalytic activity and reusability at universal pH conditions of the Co-based MGs will inspire the development of MGs in wastewater treatment.

关键词： Metallic glass Wastewater degradation Catalytic applications

Balancing resilience and efficiency in supply chains: Roles of disruptive technologies under Industry 4.0

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Frontiers of Engineering Management 2023年第1期10卷 171-176页

作者： Jing XUE guo li School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China

In the Industry 4.0 era,disruptive technologies such as big data analytics,blockchain,Internet-of-Things,and additive manufacturing have become major forces driving supply chain *** such circumstances,particular attention should be attached to balancing resilience and efficiency of the supply chain,especially in the presence of more *** this study,we first summarize the conflicts between supply chain efficiency and supply chain resilience regarding practices and ***,we discuss the positive effects of disruptive technologies in improving resilience and ***,we propose a research agenda that covers both the influence mechanism and trade-off mechanism of these technologies in terms of resilience and efficiency.

关键词： disruptive technologies supply chain resilience efficiency paradox balance