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Characteristics and visual outcomes of patients hospitalized for ocular trauma in central China: 2006-2011

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 162-168页

作者： Ying Qi Feng-Yan Zhang guang-Hua Peng Yu Zhu guang-ming wan Wen-Zhan wang Jing Ma Shi-Jie Ren Department of Ophthalmology the First Affiliated Hospital of Zhengzhou University

AIM: To complete the data of ocular trauma in central China, as a well-known tertiary referral center for ocular trauma, we documented the epidemiological characteristics and visual outcomes of patients hospitalized for ocular trauma in this region.METHODS: A retrospective study of patients hospitalized for ocular trauma in central China from 2006 to 2011 was performed.· RESULTS: This study included 5964 eyes of 5799 patients. The average age was 35.5 ±21.8y with a male-to-female ratio of 2.8:1. The most common age was 45-59 y age group. Most patients were farmers and workers(51.9%). The most common injuries were firework related(24.5%), road traffic related(24.2%), and work related(15.0%). Among the most common causative agents were firecrackers(24.5%), followed by metal/knife/scissors(21.4%). Most injuries occurred in January(14.2%),February(27.0%), and August(10.0%). There were 8.5%patients with ocular injuries combined with other injuries.The incidence of open ocular injuries(4585 eyes, 76.9%)was higher than closed ocular injuries(939 eyes, 15.7%).The incidences of chemical and thermal ocular injuries were 1.2% and 0.6%. Ocular trauma score(OTS)predicted final visual acuity at non light perception(NLP), 20/200-20/50 and 20/40 with a sensitivity of 100%,and light perception(LP) /hand motion(HM) and 1/200-19/200 with a specificity of 100%.· CONCLUSION: This study provides recent epidemiological data of patients hospitalized for ocular trauma in central China. Some factors influencing the visual outcome include time interval between injury and visit to the clinic, wound location, open or closed globe injury, initial visual acuity, and OTS.

关键词： ocular trauma score ocular trauma visual acuity

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi YU wan-li wanG Pi-guang QU Yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic performance.In this study,a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD)approach,in which the unsteady,noncompressible Reynolds Averaged Navier‒Stokes(RANS)method is used.The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions.Subsequently,the finite element model is established by considering fluid/structure interactions to study the structural stress,displacement,strain distributions and flow field information of the structure under the uniform wind speed.Finally,the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect.The variation rules of the dynamic response of the one-way and twoway fluid−structure interaction(FSI)models under different wind speeds are analyzed,and the numerical calculation results are compared with those of the centralized mass model.The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine,which in turn affects the aerodynamic performance and structural stability of the blades.The structural dynamic response of the coupled model shows significant similarity,while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model.The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the twoway FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

Palladium single atoms from melting nanoparticles on WO_(3-x) for boosted hydrogen evolution reaction

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Journal of Energy Chemistry 2024年第4期91卷 637-644页

作者： Zhongmiao Gong Zhigang Chen Hao Li guang Yang Min Yuan Zhiyun Li Xueying wan Yi Cui School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026AnhuiChina i-lab Vacuum Interconnected Nanotech WorkstationSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuChina School of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceHefei National Research Center for Physical Sciences at the MicroscaleNational Synchrotron Radiation LaboratorySchool of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

Surface-supported isolated atoms in single-atom catalysts(SACs)grant maximum utilization of metals in heterogeneous catalysis.Herein,we report a feasible pyrolysis strategy to synthesize Pd single atoms by thermally melting Pd nanoparticles on an oxygen-vacancy-rich tungsten-oxide matrix at reduction atmosphere.Near ambient pressure X-ray photoelectron spectroscopy was used to monitor the formation of zero-valence Pd single atoms and the increased metallic feature of WO_(3-x)substrate.Accordingly,the as-obtained zero-valence Pd single-atom catalyst exhibits a markedly boosted HER activity with a low overpotential(η_(10)=70 mV)at the current density of 10 mA/cm2and a small Tafel slope(b=68 mV/dec),nearly 150 mV and a 3,0-fold enhancement than those of Pd nanoparticles(η_(10)=220 mV,b=133 mV/dec)under the same conditions.In addition,quasi in situ XPS results suggest the hydrogen spillover effect is more likely to occur on Pd single atoms during the electrochemical process.Our work may pave an interesting route for the rational design of highly-efficient single-atom catalysts,and the elucidation of corresponding enhanced reaction mechanisms by the utilization of advanced characterization techniques.

关键词： Pd WO_(3-x) Single-atom catalysts NAP-XPS HER

玻璃体切割手术致眼静脉空气栓塞的研究现状及进展

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国际眼科杂志 2022年第9期22卷 1473-1477页

作者：余川万光明郑州大学第一附属医院眼科河南省郑州市450052

眼静脉空气栓塞(OVAE)是玻璃体切割手术中一种罕见的致命并发症。因手术部位靠近心脏且位于心脏上方,OVAE可能是所有手术中引起静脉空气栓塞(VAE)最严重的。随着玻璃体切割手术的发展,免缝合状态的灌注套管可出现向外滑动,使得灌注气体... 详细信息

眼静脉空气栓塞(OVAE)是玻璃体切割手术中一种罕见的致命并发症。因手术部位靠近心脏且位于心脏上方,OVAE可能是所有手术中引起静脉空气栓塞(VAE)最严重的。随着玻璃体切割手术的发展,免缝合状态的灌注套管可出现向外滑动,使得灌注气体进入脉络膜上腔,导致涡静脉撕裂。玻璃体腔气体灌注时,外伤及脉络膜黑色素瘤手术导致的脉络膜血管伤口暴露于气体中,这使得加压气体可能通过撕裂的涡静脉或异常的脉络膜静脉开口进入循环系统导致OVAE。目前OVAE的定义、发病机制、临床表现及防治措施在不断完善,但多数玻璃体视网膜外科医生和麻醉医师仍不了解该医源性并发症。提高对OVAE的认识将有助于早期发现该并发症,进而做出及时处理,同时制定有效的预防策略。通过临床和实验室研究相结合,可不断优化OVAE防治原则。充分认识OVAE的发病机理和临床特点,关注OVAE继发性病变的特征以及重视多学科间的合作有助于OVAE应急处理和预防措施的建立和完善。

关键词：眼静脉空气栓塞玻璃体切割手术气体灌注并发症涡静脉撕裂脉络膜损伤

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei Dong guang-Xi wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well operations.Deep learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis method.However,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational effort.Additionally,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different moments.Thus,there is heterogeneity in field data,which can dramatically impair the diagnostic accuracy.To solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this paper.First,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC data.Subsequently,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data heterogeneity.Finally,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the 4S-TFSM.Experiments on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational cost.To the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Atom-referenced and stabilized soliton microcomb

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 2-8页

作者： Rui Niu Shuai wan Tian-Peng Hua Wei-Qiang wang Zheng-Yu wang Jin Li Zhu-Bo wang ming Li Zhen Shen Yu Robert Sun Shui-ming Hu Brent ELittle Sai Tak Chu Wei Zhao guang-Can Guo Chang-Ling Zou Yun-Feng Xiao Wen-Fu Zhang Chun-Hua Dong State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China University of Chinese Academy of Sciences Beijing 100049China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Physics and Materials Science City University of Hong KongHong Kong 999077China State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

For the applications of the frequency comb in microresonators,it is essential to obtain a fully frequency-stabilized microcomb laser source.In this study,we present a system for generating a fully atom-referenced stabilized soliton microcomb.The pump light around 1560.48 nm is locked to an ultra-low-expansion(ULE)cavity.This pump light is then frequency-doubled and referenced to the atomic transition of87Rb.The repetition rate of the soliton microcomb is injection-locked to an atomic-clockstabilized radio frequency(RF)source,leading to mHz stabilization at 1 s.As a result,all comb lines have been frequencystabilized based on the atomic reference and the ULE cavity,achieving a very high precision of approximately 18 Hz at 1 s,corresponding to the frequency stability of 9.5×10^(-14).Our approach provides a fully stabilized microcomb experiment scheme with no requirement of f-2f technique,which could be easily implemented and generalized to various photonic platforms,thus paving the way towards the ultraprecise optical sources for high precision spectroscopy.

关键词： microcavity frequency comb dissipative Kerr solitons fully stabilized microcomb

Development of a nomogram for predicting liver transplantation prognosis in hepatocellular carcinoma

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World Journal of Gastroenterology 2024年第21期30卷 2763-2776页

作者： Li He wan-Sheng Ji Hai-Long Jin Wen-Jing Lu Yuan-Yuan Zhang Hua-guang wang Yu-Yu Liu Shuang Qiu Meng Xu Zi-Peng Lei Qian Zheng Xiao-Li Yang Qing Zhang Department of Organ Transplantation The Third Medical Centre of Chinese PLA General HospitalBeijing 100039China School of Clinical Medicine Shandong Second Medical UniversityWeifang 261053Shandong ProvinceChina Clinical Research Center The Affiliated Hospital of Shandong Second Medical UniversityWeifang 261053Shandong ProvinceChina Department of Laboratory Medicine The Third Medical Centre of Chinese PLA General HospitalBeijing 100039China Physiatry Department Naval Aviation UniversityYantai 100071Shandong ProvinceChina

BACKGROUND At present,liver transplantation(LT)is one of the best treatments for hepatocellular carcinoma(HCC).Accurately predicting the survival status after LT can significantly improve the survival rate after LT,and ensure the best way to make rational use of liver organs.AIM To develop a model for predicting prognosis after LT in patients with HCC.METHODS Clinical data and follow-up information of 160 patients with HCC who underwent LT were collected and evaluated.The expression levels of alphafetoprotein(AFP),des-gamma-carboxy prothrombin,Golgi protein 73,cytokeratin-18 epitopes M30 and M65 were measured using a fully automated chemiluminescence analyzer.The best cutoff value of biomarkers was determined using the Youden index.Cox regression analysis was used to identify the independent risk factors.A forest model was constructed using the random forest method.We evaluated the accuracy of the nomogram using the area under the curve,using the calibration curve to assess consistency.A decision curve analysis(DCA)was used to evaluate the clinical utility of the nomograms.RESULTS The total tumor diameter(TTD),vascular invasion(VI),AFP,and cytokeratin-18 epitopes M30(CK18-M30)were identified as important risk factors for outcome after LT.The nomogram had a higher predictive accuracy than the Milan,University of California,San Francisco,and Hangzhou criteria.The calibration curve analyses indicated a good fit.The survival and recurrence-free survival(RFS)of high-risk groups were significantly lower than those of low-and middle-risk groups(P<0.001).The DCA shows that the model has better clinical practicability.CONCLUSION The study developed a predictive nomogram based on TTD,VI,AFP,and CK18-M30 that could accurately predict overall survival and RFS after LT.It can screen for patients with better postoperative prognosis,and improve longterm survival for LT patients.

关键词： Hepatocellular carcinoma Liver transplantation Liver cancer Nomogram Prognosis

Projected impacts of climate change on the habitat of Xerophyta species in Africa

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Plant Diversity 2024年第1期46卷 91-100页

作者： Vincent Okelo wanga Boniface KNgarega Millicent Akinyi Oulo Elijah Mbandi Mkala Veronicah Mutele Ngumbau Guy Eric Onjalalaina Wyclif Ochieng Odago Consolata Nanjala Clintone Onyango Ochieng Moses Kirega Gichua Robert Wahiti Gituru guang-wan Hu CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Sino-Africa Joint Research Center Chinese Academy of SciencesWuhan 430074China Centre for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglun 666303China Botany Department Jomo Kenyatta University of Agriculture and TechnologyNairobiKenya East African Herbarium National Museums of KenyaP.O.Box 451660-0100NairobiKenya

Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables that affect their distribution.Therefore,predicting the impact of climate change on speciesappropriate habitats may help mitigate the potential threats to biodiversity distribution.Xerophyta,a monocotyledonous genus of the family Velloziaceae is native to mainland Africa,Madagascar,and the Arabian Peninsula.The key drivers of Xerophyta habitat distribution and preference are unknown.Using 308 species occurrence data and eight environmental variables,the MaxEnt model was used to determine the potential distribution of six Xerophyta species in Africa under past,current and future climate change scenarios.The results showed that the models had a good predictive ability(Area Under the Curve and True Skill Statistics values for all SDMs were more than 0.902),indicating high accuracy in forecasting the potential geographic distribution of Xerophyta species.The main bioclimatic variables that impacted potential distributions of most Xerophyta species were mean temperature of the driest quarter(Bio9)and precipitation of the warmest quarter(Bio18).According to our models,tropical Africa has zones of moderate and high suitability for Xerophyta taxa,which is consistent with the majority of documented species localities.The habitat suitability of the existing range of the Xerophyta species varied based on the climate scenario,with most species experiencing a range loss greater than the range gain regardless of the climate scenario.The projected spatiotemporal patterns of Xerophyta species help guide recommendations for conservation efforts.

关键词： Africa Climate change MaxEnt model Potential suitable distribution Velloziaceae Xerophyta

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汉语惊讶语步结构的多样性及其理据

新疆大学学报（哲学社会科学版） 2024年第2期52卷 150-156页

作者：万光荣刘欣婷湖南师范大学外国语学院湖南长沙410081

现代汉语中,惊讶表达的语步结构主要分为七种:反应型、提问型、评论型、反应-提问型、反应-评论型、提问-评论型、反应-提问-评论型;其中,反应型的使用频率最高,反应-提问-评论型的使用频率最低。根据程度划分的不同惊讶种类倾向采用特... 详细信息

现代汉语中,惊讶表达的语步结构主要分为七种:反应型、提问型、评论型、反应-提问型、反应-评论型、提问-评论型、反应-提问-评论型;其中,反应型的使用频率最高,反应-提问-评论型的使用频率最低。根据程度划分的不同惊讶种类倾向采用特定的语步结构:惊骇多用反应型,惊愕多用提问型或评论型,惊叹多用反应-评论型,惊奇多用提问型。汉语惊讶表达的语步结构是惊讶产生-延续机制的语言显现,并受到汉语言特点、上下文连贯等因素的影响。

关键词：惊讶表达语步结构多样性理据