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A review of medical ocular image segmentation

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虚拟现实与智能硬件（中英文） 2024年第3期6卷 181-202页

作者： Lai WEI Menghan HU Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 200241China

Deep learning has been extensively applied to medical image segmentation,resulting in significant advancements in the field of deep neural networks for medical image segmentation since the notable success of U Net in 2015.However,the application of deep learning models to ocular medical image segmentation poses unique challenges,especially compared to other body parts,due to the complexity,small size,and blurriness of such images,coupled with the scarcity of data.This article aims to provide a comprehensive review of medical image segmentation from two perspectives:the development of deep network structures and the application of segmentation in ocular imaging.Initially,the article introduces an overview of medical imaging,data processing,and performance evaluation metrics.Subsequently,it analyzes recent developments in U-Net-based network structures.Finally,for the segmentation of ocular medical images,the application of deep learning is reviewed and categorized by the type of ocular tissue.

关键词： Medical image segmentation orbit Tumor U-Net Transformer

SCIENCE AND TECHNOLOGY

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China Today 2024年第5期73卷 69-69页

China's Queqiao-2 Relay Satellite Enters Lunar orbit China's Queqiao-2 relay satellite has successfully performed a near-moon braking procedure and entered its circumlunar orbit,according to the China National Space Administration(CNSA).At 12.46 a.m.(Beijing Time)on March 25,after approximately 112 flight hours,the satellite began near-moon braking at a distance of approximately 440 kilometers from the lunar surface and entered its circumlunar orbit 19 minutes later,the CNSA said.

关键词： braking lunar orbit

Clinical characteristics and prognosis of orbital solitary fibrous tumor in patients from a Chinese tertiary eye hospital

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World Journal of Clinical Cases 2022年第27期10卷 9670-9679页

作者： Ming-Yu Ren Jing Li Yi-Xiang Wu Rui-Miao Li Chi Zhang Li-Min Liu Jing-Jing Wang Yu Gao Department of orbital Disease and Ocular Tumor Hebei Eye HospitalXingtai 054001Hebei ProvinceChina Intensive Care Unit Xingtai Third HospitalXingtai 054001Hebei ProvinceChina Department of Medical Imaging Hebei Eye HospitalXingtai 054001Hebei ProvinceChina

BACKGROUND Solitary fibrous tumor(SFT) is predominant within the pleura but very rare in the orbit,which is why the diagnosis of orbital SFT poses challenges in clinical practice.Accordingly,an integrated approach that incorporates specific clinical features,histological,histopathological,and immunohistochemical(IHC) examinations,and molecular analyses is warranted.AIM To retrospectively explore the clinical and imaging characteristics,treatment,outcomes of a series of patients with orbital SFT.METHODS We conducted a retrospective review of a series of patients diagnosed with a histopathologic orbital SFT treated at a single institution.All data on demographics,clinical characteristics,imaging,treatment,postoperative histopathological and IHC examinations,and prognosis were collected.RESULTS In total,13 patients were enrolled,7(53.8%) of whom had the tumor located in the superomedial quadrant of the orbit.Computed tomography revealed a solitary ovoid lesion in 10(76.9%) patients and irregular lesion in 3(23.1%) patients.Magnetic resonance imaging results were as follows:On T1 weighted images,3(23.1%) patients had hypointense mixed signals,whereas 10(76.9%) patients showed isointense mixed signals;on T2 weighted images(T2 WI),3(23.1%),4 (30.8%),and 6(46.2%) patients exhibited hypointense mixed,isointense mixed,and hyperintense signals,respectively.Notably,12(92.3%) patients showed significant enhancement,whereas there were patchy slightly enhanced areas in the tumor.All patients were treated by surgery.IHC analysis demonstrated that the tumor cells were immunoreactive for CD34,CD99,STAT-6,and vimentin in all patients.The lesions showed Ki-67 positivity 10% in 2(15.4%).Two(15.4%) patients exhibited tumor recurrence.CONCLUSION The clinical manifestations and radiologic characteristics of orbital SFT are diverse and not specific.Accurate diagnosis and treatment require detailed radiological and histopathological/IHC evaluation.

关键词： orbit Solitary fibrous tumor Diagnostic imaging Immunohistochemistry Surgical therapy

Tandem Co–O dual sites on halloysite with promoted reaction kinetics for sulfur reduction

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Journal of Energy Chemistry 2022年第12期75卷 486-493,I0013页

作者： Qiang Zhang Yinyin Qian Ji-Jun Zou Ruijie Gao Huaming Yang Engineering Research Center of Nano-Geomaterials of Ministry of Education China University of GeosciencesWuhan 430074HubeiChina Hunan Key Laboratory of Mineral Materials and Application School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083HunanChina Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074HubeiChina Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Key Laboratory of Functional Geomaterials in China Nonmetallic Minerals Industry China University of GeosciencesWuhan 430074HubeiChina

Facilitating sulfur reduction reaction(SRR)is a promising pathway to tackle the polysulfide shuttle effect and enhance the electrochemical performance of lithium-sulfur(Li-S)batteries.Catalysts with a solo active site can reduce a reaction barrier of a certain transition-intermediate,but the linear scaling relationship between multi-intermediates still obstructs overall SRR.Herein,we construct tandem Co–O dual sites with accelerating SRR kinetics by loading highly dispersed cobalt sulfide clusters on halloysite.This catalyst features Co with upshifted d-orbital and O with downshifted p-orbital,which cooperatively adsorb long-chain polysulfide and dissociate an S–S bond,thus achieving both optimal adsorption–desorption strength and reduced conversion energy barrier of multi-intermediates in SRR.The Li-S coin batteries using the electrocatalyst endows a high specific capacity of 1224.3 m Ah g^(-1)at 0.2 C after 200cycles,and enhances cycling stability with a low-capacity decay rate of 0.03%per cycle at 1 C after1000 cycles.Moreover,the strategy of the tandem Co–O dual sites is further verified in a practical Li-S pouch battery that realizes 1014.1 m Ah g^(-1)for 100 cycles,which opens up a novel avenue for designing electrocatalysts to accelerate multi-step reactions.

关键词： Sulfur reduction reaction Dual catalytic site orbit Li-S battery

Clinical Characteristics and Endoscopic Endonasal Removal of Foreign Bodies within Sinuses, orbit, and Skull Base

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Chinese Medical Journal 2017年第15期130卷 1816-1823页

作者： Yi-Hui Wen Wei-Jian Hou Wen-Bin Lei Feng-Hong Chen Xiao-Lin Zhu Zhang-Feng Wang Ren-Qiang Ma Wei-Ping Wen Department of Otolaryngology The First Affiliated Hospital Otolaryngology Institute Sun Yat-sen University Guangzhou Guangdong 510080 China Department of Otolaryngology Head and Neck Surgery Kiang Wu Hospital Macao 999078 China

Background：Foreign bodies within the sinuses,orbit,and skull base （FBSOS） are rare;hence,diagnosis and management guidelines are lacking.Endoscopic sinus surgery （ESS） removal is preferred because of the less invasiveness and minimal morbidity.This study was designed to summarize clinical experience with ESS management of FBSOS.Methods：We retrospectively reviewed clinical manifestations,imaging findings,treatment,and outcomes in consecutive patients with ESS removal of FBSOS between 2004 and 2015 at a tertiary academic medical center.The Chi-square test was performed to compare the infection rate between wooden and nonwooden FBSOS.Results：There were 23 male and five female patients,with median age of 11 years.FBSOS were located within the sinuses （86%）,orbit （75%）,and skull base/intracranial region （46%）.Wooden FBSOS had a significantly higher risk of infection （78%） compared with nonwooden FBSOS （5%,P 〈 0.05）.Contrast-enhanced computed tomography （CT） plus three-dimensional reconstruction was sensitive in all cases.Twenty-seven （96%） FBSOS were removed by ESS alone,while 1 （4%） FBSOS was removed using the combined ESS and lateral cervical approach.Four of the nine intracranial penetrating FBSOS patients had intraoperative cerebrospinal fluid （CSF） leak and received endoscopic CSF leak repair.Twelve （43%） patients suffered complications （meningitis,diplopia,and vision loss）.Conclusions：ESS is a minimally invasive,safe,and promising surgical approach for FBSOS removal.Contrast-enhanced CT is effective in preoperative diagnosis and intraoperative guidance.Wooden FBSOS had higher risk of infection,thus antibiotics are recommended.

关键词： Foreign Body orbit Paranasal Sinuses Skull Base

orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2,3,4,HU XiaoGong2,4,LIU Li1,WU XiaoLi1,HUANG Yong2,4 & HE Feng1 1 Beijing Global Information Application and Development Center,Beijing 100094,China 2 Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China 3 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 4 Space Navigation and Positioning Technology,Laboratory of Shanghai Municipal,Shanghai 200030,China Beijing Global Information Application and Development Center Beijing China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing China Space Navigation and Positioning Technology Laboratory of Shanghai Municipal Shanghai China

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation system.Simulation experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging data.This strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time available.With the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction parameters.The error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging data.Using data collected for a Chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is achievable.The root-mean-square(RMS) of the post-fit C-band ranging data is about 0.203 m,and the RMS of the post-fit pseudorange is 0.408 m.Radial component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 m.The SLR evaluation also suggests that for 2-h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 ns.Even for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.280 m and the 2-h predicted radial error of 0.888 m.Clock synchronization between the GEO and tracking statio

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

orbit design for the Laser Interferometer Space Antenna (LISA)

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 179-186页

作者： Gerhard HEINZEL Albrecht RDIGER Max Planck Institute for Gravitational Physics

The Laser Interferometer Space Antenna (LISA) is a joint ESA-NASA mission for detecting low-frequency gravitational waves in the frequency range from 0.1 mHz to 1 Hz, by using accurate laser interferometry between three spacecrafts, which will be launched around 2018 and one year later reach their operational orbits around the Sun. In order to operate successfully, it is crucial for the constellation of the three spacecrafts to have extremely high stability. Based on the study of operational orbits for a 2015 launch, we design the operational orbits of beginning epoch on 2019-03-01, and introduce the method of orbit design and optimization. We design the orbits of the transfer from Earth to the operational orbits, including launch phase and separation phase; furthermore, the relationship between energy requirement and flight time of these two orbit phases is investigated. Finally, an example of the whole orbit design is presented.

关键词： co-orbital restricted problem orbit design orbit optimization launch energy

orbit Design Elements of Chang’e 5 Mission

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Space(Science & Technology) 2021年第1期2021卷 28-49页

作者： Zhong-Sheng Wang Zhanfeng Meng Shan Gao Jing Peng Beijing Institute of Spacecraft System Engineering Beijing 100094China

The three key orbit design technologies employed in the Chang’e 5 mission are identified and discussed in this paper:orbit design for lunar orbit rendezvous and docking,orbit design for precision lunar landing and inclination optimization,and orbit design for Moon-to-Earth transfer.First,an overview of the Chang’e 5 mission profile is presented,which is followed by detailed discussions of the three key orbit design technologies,including an introduction of the tracking-based orbit design methodology.Flight data are provided to demonstrate the correctness of the designs.

关键词： discussions orbit Earth

Natural killer T-cell lymphoma originating from the orbit

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Chinese Medical Journal 2012年第9期125卷 1677-1680页

作者： DAI Wei ZHONG Ming SHEN Wei ZOU Ke BAI Chen-guang Department of Ophthalmology Changhai Hospital Shanghai 200433 China Department of Ophthalmology People＇s Hospital of Linshui Guang＇an Sichuan 638500 China Department of Pathology Changhai Hospital Shanghai 200433 China

Natural killer T-cell lymphoma （NKTL） is a malignant neoplasm which usually involves the nasal cavity or paranasal sinuses, while an orbit origin is extremely rare. Here we report the clinical, radiological and histopathologic features of a patient with NKTL originating from the orbit. We analyzed the clinical and radiologic records in the whole course of the disease. We also reviewed the morphology and immunohistochemistry of the neoplasm biopsy, including the presence of CD56, CD3 and cytotoxic molecules. This case demonstrated that nasal-type NKTL with a poor prognosis can originate from the orbit.

关键词： lymphoma natural killer T-cell orbit CD56