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Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease

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World Journal of Gastroenterology 2025年第3期31卷 62-72页

作者： Hao Ding Yuan-Yuan Fang Wen-Jie Fan chen-Yu zhang Shao-Fei Wang Jing Hu Wei Han Qiao Mei Department of Gastroenterology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Radiation Oncology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Gastroenterology Suzhou First People's HospitalSuzhou 234099Anhui ProvinceChina

BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD ***,it poses a significant challenge due to its limited accessibility through conventional endoscopic *** To establish a noninvasive radiomic model based on computed tomography enterography(CTE)for MH assessment in SBCD *** Seventy-three patients diagnosed with SBCD were included and divided into a training cohort(n=55)and a test cohort(n=18).Radiomic features were obtained from CTE images to establish a radiomic *** demographics were analysed to establish a clinical model.A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic *** diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),*** Of the 73 patients enrolled,25 patients achieved *** radiomic-clinical nomogram had an area under the ROC curve of 0.961(95%confidence interval:0.886-1.000)in the training cohort and 0.958(0.877-1.000)in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone,as demonstrated by *** These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients.

关键词： Crohn’s disease Computed tomography enterography Mucosal healing Nomogram Radiomics

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda zhang Weimin Yuan Zhixing Ling Yong chen Nanda Rea Arne Rau Zhiming Cai Huaqing cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing zhang chen zhang Shuang-Nan zhang Yonghe zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian zhang Zipei Zhu Hu Zou Congying Bao Fansheng chen Houlei chen Tianxiang chen Wei chen Yehai chen Yifan chen chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan zhang Mo zhang Wenjie zhang Zhen zhang Zhen zhang Ziliang zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Mechanism of Locust Air Posture Adjustment

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Journal of Bionic Engineering 2015年第3期12卷 418-431页

作者： Diansheng chen Kewei chen Ziqiang zhang Benguang zhang Robotic Institute in School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

Stimulated locusts often tumble during the jumping process. Locusts can also recover their bodies in the air for flight or landing stability. To increase jumping distance and avoid landing collision of bio-inspired jumping robots, the mechanism of air posture adjustment of locusts is examined in this research. This mechanism can be used to improve the stability of robot. The abdomen swings, wing motions, and the variations in body angle are recorded by a high-speed camera when locusts free fall in air with normal or upside-down initial posture. Results indicate that the wings and abdomen are mainly utilized for air posture adjustment. Moreover, abdomen swing and forewing rotation have positive effects on body pitch. However, locusts have dif- ficulty in recovering their bodies from the upside-down posture without wings, although the body pitch caused by unpredictable perturbation in air can be compensated through abdomen swing. Consequently, body roll is attributed to the wing motion, which is related to two factors, namely, the different flapping amplitudes of the wings on both sides, and the different flapping velocities of wings during the upstroke and downstroke periods. This research may provide reference for the design of jumping robots.

关键词： locusts air posture adjustment abdomen swing asymmetric flapping wings

Investigation of a spherical-section ultrasound phased array for hepatic ablation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1237-1245页

作者： zhang chen-xi chen Ya-zhu Institute of Biomedical Instrument Shanghai Jiao Tong University Shanghai 200030 China

A 3D ultrasound thermal model with a 3D finite element representation for modeling the thermal diffusion effects for hepatic ablation induced by spherical-section ultrasound phased array was developed. The model was first validated against available published measured data in rat liver. Using the validated model,effects of blood perfusion and heating schemes on lesion formation were studied for both single focus and split-focus intensity patterns. It was shown that for single focus sonication pattern the short-duration(～2 s) and high-intensity(～1250 W/cm2) heating scheme can completely reduce the cooling effect of the blood perfusion. The lesion shape and size were significantly altered by perfusion for split-focus pattern even with a rapid heating scheme when the focus spacing was larger than 2.4 mm. Underdosed areas might be present between two foci. Prolonging ex-posure time or shortening focus spacing can reduce the cool region between two foci. In addition,the influences of thermal and acoustic parameters were also studied. When the therapy depth is short(<5 cm) ,the lesion size monotonically increases with increasing attenuation coefficient that ranges from 5.4 to 11 Np/(m?MHz) .

关键词： Ultrasound phased-army Blood perfusion Temperature distribution Numerical simulation

Investigation of the Anisotropic Morphology-Induced Effects of the Slippery Zone in Pitchers of Nepenthes alata

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Journal of Bionic Engineering 2015年第1期12卷 79-87页

作者： Pengfei zhang Huawei chen Deyuan zhang School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

Plant of carnivorous genus Nepenthes alata has evolved specific pitchers to prey insects for survival in the barren habitat, especially its slippery zone. The excellent slippery function has received considerable interest because of its potential applica- tion in antifriction surface design. The surface morphologies of intact and de-waxed slippery zones were characterized using scanning electron microscope and scanning white-light interferometer. Hierarchical structures with anisotropic micro- lunate structure and nano- wax crystals were found on the slippery zone. Due to the hierarchical structures, the slippery zone is hy- drophobic. It shows a significant anisotropic wettability with static contact angles 153.3° and 140.1° in the directions perpen- dicular and parallel to the upward direction （toward the peristome）, respectively. The sliding angles are -3° and -10° in the downward and upward directions, respectively. Crawling experiments indicate that the microscopic surface roughness and the brittleness of the wax crystals may reduce insect attachment in different modes according to the insect mass differences. Moreover, artificial slippery surfaces inspired by the slippery zone of Nepenthes alata were fabricated. Traction experiments quantitatively verified that the friction force of replicated lunate structures with Ra-2.54 μm surface roughness was reduced by about 25% as compared to flat surface with Ra-0.56 μm surface roughness for cricket claws.

关键词： biomimetic surface anisotropic wettability antifriction slippery surface Nepenthes alata

Novel TPN control algorithm for exoatmospheric intercept

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1290-1295页

作者： chen Lei zhang Bing Coll. of Aerospace and Material Engineering National Univ. of Defense Technology Changsha 410073 P. R. China

A novel control algorithm with fixed pulse thrust, based on true proportional navigation（TPN）, is proposed for exoatmospheric *** to the TPN guidance law and pulse thrust characteristics, the principle of control command is presented, the control stability and precision are *** the help of the TPN guidance law, the algorithm can automatically modulate the turn-on time and duration of the thrust, which could effectively limit the impact of measure noise of the line-of-sight（LOS） angle and rate on the interception *** last, the number-theoretic method（NTM） is introduced to acquire the relation between control algorithm and miss-distance, even as it simulates the intercept process with initial state *** the reliability of the algorithm is demonstrated with the simulation result.

关键词： exoatmospheric intercept true proportional navigation pulse thrust control algorithm numbertheoretic method.

Fast Fading Channel Estimation for OFDM Systems with Complexity Reduction

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Chinese Journal of Electronics 2021年第6期30卷 1173-1177页

作者： zhang chen LI Dan College of Electronic Science and Technology National University of Defense Technology

Channel estimation plays a significant role in the Inter-carrier interference(ISI) mitigation and symbol detection in Orthogonal frequency division multiplexing(OFDM) systems. As the speed of mobile terminal increases, the channel changes rapidly, causing fast fading which will degrade the system performance. In this paper, a low complexity fast fading channel estimation method suited for scattered pilot OFDM systems is proposed. This method is characterized by estimating channel matrix directly in the frequency domain, which can significantly reduce the channel estimation complexity with good system performance. Simulation results verify its superiority over the existing estimation methods.

关键词： low complexity fast fading channel estimation OFDM modulation existing estimation methods channel estimation OFDM systems mobile terminal increases good system performance symbol detection channel estimation complexity frequency-domain analysis channel changes fading channels complexity reduction channel matrix

A super-high angular resolution principle for coded-mask X-ray imaging beyond the diffraction limit of a single pinhole

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Chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 333-340页

作者： chen zhang Shuang-Nan zhang Department of Engineering Physics ＆ Center for Astrophysics Tsinghua University Beijing 100084 China Key Labora.tory of Particle Astrophysics Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China Department of Physics ＆ Center for Astrophysics Tsinghua University Beijing 100084 China

High angular resolution X-ray imaging is always useful in astrophysics and solar physics. In principle, it can be performed by using coded-mask imaging with a very long mask-detector distance. Previously, the diffraction-interference effect was thought to degrade coded-mask imaging performance dramatically at the low energy end with its very long mask-detector distance. The diffraction-interference effect is described with numerical calculations, and the diffraction-interference cross correlation reconstruction method （DICC） is developed in order to overcome the imaging performance degradation. Based on the DICC, a super-high angular resolution principle （SHARP） for coded-mask X-ray imaging is proposed. The feasibility of coded mask imaging beyond the diffraction limit of a single pinhole is demonstrated with simulations. With the specification that the mask element size is 50 × 50 μm^2 and the mask-detector distance is 50 m, the achieved angular resolution is 0.32arcsec above about 10keV and 0.36arcsec at 1.24keV （λ = 1 nm）, where diffraction cannot be neglected. The on-axis source location accuracy is better than 0.02 arcsec. Potential applications for solar observations and wide-field X-ray monitors are also briefly discussed.

关键词： instrumentation high angular resolution - techniques image processing - telescopes

Development of the super high angular resolution principle for X-ray imaging

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Research in Astronomy and Astrophysics 2011年第1期11卷 119-124页

作者： chen zhang Shuang-Nan zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Physics ＆ Center for Astrophysics Tsinghua University Beijing 100084 China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy ofSciences Beijing 100049 China

Development of the Super High Angular Resolution Principle （SHARP） for coded-mask X-ray imaging is presented. We prove that SHARP can be considered as a generalized coded mask imaging method with a coding pattern comprised of diffraction-interference fringes in the mask pattern. The angular resolution of SHARP can be improved by detecting the fringes more precisely than the mask＇s element size, i.e. by using a detector with a pixel size smaller than the mask＇s element size. The proposed mission SHARP-X for solar X-ray observations is also briefly discussed.

关键词： instrumentation: high angularresolution-- techniques: image processing-- telescopes