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ProNet Adaptive Retinal Vessel Segmentation Algorithm Based on Improved UperNet Network

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Computers, Materials & Continua 2024年第1期78卷 283-302页

作者： Sijia Zhu Pinxiu Wang ke shen CW Chu College Jiangsu Normal UniversityXuzhou221000China Biomedical Engineering College Southern Medical UniversityGuangzhou510080China

This paper proposes a new network structure,namely the ProNet *** medical image segmentation can help clinical diagnosis of related eye diseases and is essential for subsequent rational *** baseline model of the ProNet network is UperNet(Unified perceptual parsing Network),and the backbone network is ConvNext(Convolutional Network).A network structure based on depth-separable convolution and 1×1 convolution is used,which has good performance and *** further optimise ProNet mainly in two *** is data enhancement using increased noise and slight angle rotation,which can significantly increase the diversity of data and help the model better learn the patterns and features of the data and improve the model’s ***,it can effectively expand the training data set,reduce the influence of noise and abnormal data in the data set on the model,and improve the accuracy and reliability of the *** is the loss function aspect,and we finally use the focal loss *** focal loss function is well suited for complex tasks such as object *** function will penalise the loss carried by samples that the model misclassifies,thus enabling better training of the model to avoid these errors while solving the category imbalance problem as a way to improve image segmentation density and segmentation *** the experimental results,the evaluation metrics mIoU(mean Intersection over Union)enhanced by 4.47%,and mDice enhanced by 2.92% compared to the baseline *** generalization effects and more accurate image segmentation are achieved.

关键词： Retinal segmentation multifaceted optimization cross-fusion data enhancement focal loss

Decreasing intraocular pressure significantly improves retinal vessel density,cytoarchitecture and visual function in rodent oxygen induced retinopathy

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Science China(Life Sciences) 2020年第2期63卷 290-300页

作者： Rui Du Xu Wang ke shen Shigang He School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China Bio-X Institute Shanghai Jiao Tong UniversityShanghai 200240China

We attempted to explore a noninvasive,easily applicable and economically affordable therapy for retinopathy of prematurity(ROP).Rat pups were raised in 80%oxygen from postnatal day 7 to P12,and returned to room *** eye drops were administered twice a day for 7 days,to reduce intraocular pressure(IOP)by about 20%.Immunohistochemical staining was performed to visualize vessel endothelial cells,to analyze retinal neurons and *** experiments were carried out to test visual acuity and contrast *** the end of the 7-day treatment,the number of vessels extending to the vitreous body was significantly reduced and retinal vessel density *** improvement was maintained to the end of the12 th *** the central retina of the model group,the horizontal cells were completely wiped out,the outer plexiform layer was undetectable,and the rod bipolar cell dendrites sprouted into the outer nuclear *** treatment partially reverted these architectural *** importantly,behavioral experiments revealed significantly improved visual acuity and contrast sensitivity in the treated ***,reducing IOP could potentially serve as a safe and economical measure to treat ROP.

关键词： oxygen induced retinopathy vessel plasticity visual acuity contrast sensitivity rat

Buckling of composite cylindrical shells with ovality and thickness variation subjected to hydrostatic pressure

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Defence Technology（防务技术） 2022年第5期18卷 862-875页

作者： Zhun Li ke-chun shen Xin-hu Zhang Guang Pan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an710072China key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi'an710072China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China

The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic *** this study,ovality and thickness variations as two representative types of the geometric imperfections are *** measuring the geometric imperfections,a typical carbon fiber reinforced polymers(CFRP)cylindrical shell is tested to obtain the buckling *** buckling behaviors of the shell sample are analyzed in combination with the strain *** using the nonlinear numerical analysis,the buckling shapes of the CFRP cylinder shells with different combinations of ovality and thickness variation are firstly *** rules of influence of such imperfections on the buckling pressure are then obtained by nonlinear regression ***,an empirical formula is proposed to predict the buckling pressure of the composite cylinder shells,and the calculated results from the formula are in good agreement with the numerical results.

关键词： Composite Cylindrical shell Buckling Hydrostatic pressure Imperfections

Long-lasting impairments in rodent oxygen-induced retinopathy measured by retinal vessel density and visual function

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Science China(Life Sciences) 2019年第5期62卷 681-690页

作者： Xu Wang ke shen Fang Lu Shigang He School of Biomedical Engineering Institute of Natural Sciences and Bio-X Institute Shanghai Jiao Tong University Department of Ophthalmology West China Hospital Sichuan University

In mild or moderate retinopathy of prematurity(ROP), retinal vessels undergo obliteration, proliferation, and regression. Despite complete regression of vessel abnormalities, a variety of visual impairments have been reported. Rodent oxygen-induced retinopathy(OIR) is widely used as a model to study ROP. However, the long-term changes of OIR model remain unclear. The aim of this study is to examine long term changes of retinal vessel and visual function in a rodent OIR model resembling human mild or moderate ROP. In this study, after subjecting the animals to 80% oxygen(O_2) for 5–7 d, the retinal vessel density at postnatal day 12(P12) was approximately 30% lower than that in the age-matched control, but this difference was not significant between the groups. Vessel abnormalities, such as vessel tortuosity, neovascular tufts, and the number of vessels protruding into the vitreous, peaked between P17 and P20. Despite the regression of many abnormalities, vessel density in the OIR group was 36% and 32% lower than that in the control animals at 6 weeks and 4 months, respectively. The visual acuity and contrast sensitivity were impaired in the OIR group when measured at 2, 3 and 4 months. Therefore, the rodent OIR model exhibited long-lasting reduction in retinal vessel density and visual impairments, similar to those observed in mild or moderate human ROP. This study suggests that the rodent OIR model can be used to explore possible interventions for mild and moderate human ROP.

关键词： oxygen-induced retinopathy vessel plasticity visual acuity contrast sensitivity rat

Controlling Chaotic Behavior in a Bose-Einstein Condensate with Linear Feedback

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Communications in Theoretical Physics 2008年第7期50卷 215-219页

作者： WANG Zhi-Xiu ZHANG Xi-He shen ke Department of Physics Changchun University of Science and Technology Changchun 130022 China Aviation University of Air Force Changchun 130022 China

The spatial structure of a Bose-Einstein condensate （BEC） loaded into an optical lattice potential is investigated and the spatially chaotic distributions of the condensates are revealed. A method of chaos control with linear feedback is presented in this paper. By using the method, we propose a scheme of controlling chaotic behavior in a BEC with atomic mirrors. The results of the computer simulation show that controlling the chaos into the stable states could be realized by adjusting the coefficient of feedback only if the maximum Lyapunov exponent of the system is negative.

关键词： controlling chaos BEC linear feedback Lyapunov exponent

A Reflection on the 2017 Nobel Prize for Physiology and Chinese Medicine

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Chinese Journal of Integrative Medicine 2020年第11期26卷 867-872页

作者： XING Meng QU ke-shen HUANG Yu XING Yu-rui Department of Dermatology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai(200437)China Department of Chinese Medicine Surgery Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai(200032)China Shaanxi University of Chinese Medicine Xi'an(712046)China

Research on the molecular mechanisms controlling circadian rhythm in Western medicine is comparable to the study of a day-night rhythm in Chinese medicine(CM),as also focus on the same life *** comparing the two,this paper elaborates on the differences between them in their respective issues of consciousness,ways of thinking,research methods and research *** speaking,Nobel Prize research has a stronger sense of the problems and concerns about the essence of“what”,while CM focuses on“how a thing functions”.The former mainly adopts experimental and mathematical methods,while the latter primarily depends on observation and *** natural philosophy and natural science eventually lead to the results and the inevitable,quantitative and qualitative *** on the life rhythm in CM should be proposed,scientific problems should be fully grasped,and research should be carried out with the aid of multidisciplinary new knowledge and new achievements through cross-disciplinary *** the basis of clinical epidemiological research and experimental research,a systematic review should be made of the human physiology of CM and the pathological rhythm model to explore the regulatory mechanism of time rhythm and create a new theory of time medicine.

关键词： Nobel Prize Chinese medicine contrast between Chinese medicine and Western medicine

Ecosystem service of green infrastructure for adaptation to urban growth:function and configuration

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Ecosystem Health and Sustainability 2018年第5期4卷 20-31页

作者： Yun-Cai Wang Jia-ke shen Wei-Ning Xiang Department of Landscape Architecture Center for Ecophronetic Practice ResearchCollege of Architecture and Urban PlanningTongji UniversityShanghaiChina Department of Geography and Earth Sciences the University of North Carolina at CharlotteCharlotteNCUSA

Objectives:(1)to explore what kind of green infrastructure(GI)meets the demand for urban ecological security of rapid urbanization areas;(2)to figure out how to determine the specific function and configuration of GI from ecosystem service requirements of urban ecological ***:(1)Through the literature review,this article summarizes the function and structure evolution of GI in order to adapt to urban growth.(2)Standing on the imperfect ecological functions and unreasonable spatial configurations,this article builds up a conceptual model for the optimization of green infrastructure ecosystem services to meet the demand for the green infrastructure pattern needed by urban ***:The optimization framework consists of four central function modules and its regulating and controlling mechanisms,incuding:(1)Balancing supply and demand of GI's ecosystem service;(2)Measuring and evaluating GI's ecosystem services;(3)Elevating and optimizing GI's ecosystem service;(4)Building urban ecological security patterm with high efficiency of GI's ecosystem ***,this framework provides guidance for the planning and design of GI and the urban ecological security pattern building in rapid urbanization areas based on ba lancing supply and demand of GI's ecosystem ***:The conceptual model of Gl's ecosystem service optimization based on balan-cing supply and demand shows a new path to meet the needs of urban growth and build a city's ecological security pattern through upgrading and optimizing GI.

关键词： Green infrastructure ecosystem service urban growth balancing supply and demand optimization framework

The Calcineurin B-Like Ca2＋ Sensors CBL1 and CBL9 Function in Pollen Germination and Pollen Tube Growth in Arabidopsis

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Molecular Plant 2013年第4期6卷 1149-1162页

作者： Anette Maihs Leonie Steinhorst Jian-Pu Han Li-ke shen Yi Wang Jorg Kudla Institut for Biologie und Biotechnologie der Pflanzen Universitat MOnster Schlossplatz 4 48149 MOnster Germany State key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences National Plant Gene Research Center (Beijing) China Agricultural University Beijing 100193 China

Ca2＋ has been established as an important second messenger regulating pollen germination and tube growth. However, to date, only a few signaling components have been identified to decode and relay Ca2＋ signals in growing pollen tubes. Here, we report a function for the calcineurin B-like （CBL） Ca2＋ sensor proteins CBL1 and CBL9 from Arabidopsis in pollen germination and tube growth. Both proteins are expressed in mature pollen and pollen tubes and impair pollen tube growth and morphology if transiently overexpressed in tobacco pollen. The induction of these phenotypes requires efficient plasma membrane targeting of CBL1 and is independent of Ca2＋ binding to the fourth EF-hand of CBL1. Overexpression of CBL1 or its closest homolog CBL9 in Arabidopsis renders pollen germination and tube growth hypersensitive towards high external K＋ concentrations while disruption of CBL1 and CBL9 reduces pollen tube growth under low K~ conditions. Together, our data identify a crucial function for CBL1 and CBL9 in pollen germination and tube growth and suggest a model in which both proteins act at the plasma membrane through regulation of K＋ homeostasis.

关键词： calcium CBL pollen tube growth potassium

Enhancing Dehydration Performance of Isopropanol by Introducing Intermediate Layer into Sodium Alginate Nanofibrous Composite Pervaporation Membrane

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Advanced Fiber Materials 2019年第2期1卷 137-151页

作者： Peiyun Li Cheng Cheng ke shen Tonghui Zhang Xuefen Wang Benjamin S.Hsiao State key Lab for Modification of Chemical Fibers and Polymer Materials Donghua UniversityShanghai 201620People’s Republic of China Department of Chemistry Stony Brook UniversityStony BrookNY 11794USA

A novel three-tier composite membrane based on highly porous nanofibrous substrate was demonstrated for efficient iso-propanol dehydration by ***,polyethyleneimine(PEI)modified graphene oxide(GO)sheets were vacuum-assistant assembled onto porous electrospun polyacrylonitrile(PAN)nanofibrous substrate to achieve a smooth,hydrophilic and compact PEI-GO intermediate *** introduction of PEI chains endowed GO interlayer with sufficient interaction for bonding adjacent GO nanosheets to enhance stability in water/isopropanol mixture and also with the ascended inter-lamellar space to improve the water-sorption ability due to the abundant active amino *** from PEI-GO layer,a defect-free sodium alginate(SA)skin layer could be facilely manufactured with elaborately controlled thickness as thin as possible in order to reduce mass transfer resistant and enhance permeability ***,the interlayer would also contribute to enhance interfacial adhesion to promote the structure integrity of three-tier thin-film nanofibrous composite(TFNC)membrane in pervaporation dehydration *** fine-tuning of membrane preparation process,the SA/PEI(75)-GO-60/PAN TFNC membrane exhibited competitive pervaporation performance with the permeate flux of 2009 g/m2 h and the separation factor of 1276 operated at 70°C for dehydration of 90 wt%isopropanol *** unique three-tier composite membrane structure suggested an effective and facile approach to design novel membrane structure for further improvement of pervaporation performance.

关键词： Polyethyleneimine modified graphene oxide Intermediate layer Thin-film nanofibrous composite membrane Pervaporation membrane