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Fully Chemical Recyclable Poly(γ-butyrolactone)-based Copolymers with Tunable Structures and Properties

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Chinese Journal of Polymer Science 2022年第5期40卷 456-461页

作者： yi-Huan Liu Xin Yuan Jia-Qi wu Ming-xuan Luo Xin Hu Ning Zhu Kai Guo Collegeof Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjing 211800China Collegeof Materials Science and Engineering Nanjing Tech UniversityNanjing 211800China State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 211800China

The emerging chemical recyclable polymers,such as poly(γ-butyrolactone)(PGBL)and poly((R)-3,4-trans six-membered ring-fused GBL)(P((R)-M)),provide a good solution to the plastic ***,these homopolymers suffer from limited structures and ***,we reported a fully chemical recyclable copolymer P(GBL-co-((R)-M))through ring-opening copolymerization(ROCOP)of GBL and(R)-*** employing organomagnesium as the catalyst and regulating the reaction conditions,the chemical structures of copolymers were wellcontrolled(GBL content=13%-78%,Mn=6560-15600 g/mol,DM=1.08-1.59).The resultant P(GBL-co-((R)-M))exhibited fully chemical recyclability,which rapidly and quantitatively depolymerized into initial GBL and(R)-M monomer through *** varying GBL content,tunable thermal properties were achieved for P(GBL-co-((R)-M)).The onset decomposition temperatures of copolymers varied from 193°C to 234°C.A linear evolution of glass transition temperature(T_(g))of P(GBL-co-((R)-M))versus GBL content was obtained as following equation of Tg=-1.06×GBL mol%×100+*** hope that the reported fully chemical recyclable copolymers with tunable structures and properties would serve as the candidate material for sustainable applications.

关键词： Poly(γ-butyrolactone)-based copolymers Ring-opening copolymerization Chemical recyclability Organomagnesium

Fine-Grained Action Recognition Based on Temporal Pyramid Excitation Network

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Intelligent Automation & Soft Computing 2023年第8期37卷 2103-2116页

作者： xuan Zhou Jianping yi School of Mechanical&Electrical Engineering Xi’an Traffic Engineering InstituteXi’an710300China School of Electronics and Information Xi’an Polytechnic UniversityXi’an710048China

Mining more discriminative temporal features to enrich temporal context representation is considered the key to fine-grained action *** action recognition methods utilize a fixed spatiotemporal window to learn local video ***,these methods failed to capture complex motion patterns due to their limited receptive *** solve the above problems,this paper proposes a lightweight Temporal Pyramid Excitation(TPE)module to capture the short,medium,and long-term temporal *** this method,Temporal Pyramid(TP)module can effectively expand the temporal receptive field of the network by using the multi-temporal kernel decomposition without significantly increasing the computational *** addition,the Multi Excitation module can emphasize temporal importance to enhance the temporal feature representation *** can be integrated into ResNet50,and building a compact video learning *** validation experiments on several challenging benchmark(Something-Something V1,Something-Something V2,UCF-101,and HMDB51)datasets demonstrate that our method achieves a preferable balance between computation and accuracy.

关键词： Fine-grained action recognition temporal pyramid excitation module temporal receptive multi-excitation module

A Three-row Opposed Gripping Mechanism with Bioinspired Spiny Toes for Wall-climbing Robots

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Journal of Bionic Engineering 2019年第6期16卷 994-1006页

作者： Chao Xie xuan wu Xiaojie Wang Institute of Advanced Manufacturing Technology Hefei Institutes of Physical ScienceChinese Academy of SciencesChangzhou 213164China Department of Precision Machineiy and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China

This paper presents a study of a three-row opposed gripping mechanism made of bioinspired spiny *** insect Serica orientalis Motschulsky's tarsal system was first described and studied.A compliant single spiny toe model was established assuming that the contact asperities were *** the single toe contact model,a spiny toe array's contact model was then developed using asperity height's distribution *** studying the cngaging and disengaging process of the single toe,the mechanical behavior of the toe and toe array were *** toes as well as the arrays were manufacturcd via rapid prototyping.A customized apparatus using dis-placement-control method has been carried out to measure the pull-in forces and pull-ofT positions of the single toe and toe array undcr various compression *** on the understanding,a three-row opposed gripping mechanism with radial configuration for wall-climbing robots was designed and fabricated according to the mechanical behaviors of the toe and *** an opposed spoke con figuration with 3 rows of 31 toes on each linkage array,the mechanism designed as a foot of climbing robots can vertically resist at least 1 kg of load on rough inverted surface,while the maximum normal load is as high as 31 *** findings may provide a way in developing a high payload wall-climbing robot system for practical applications.

关键词： bioinspired spiny toe contact mechanical model opposed gripping mechanism wall-climbing robot

Experimental Study of Operation Performance for Hydrocarbon Fuel Pump with Low Specific Speed

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Journal of Thermal Science 2017年第5期26卷 440-447页

作者： wu Xianyu YANG Jun JIN xuan College of Aerospace Science and Engineering National Univ. of Defense Technology ChangSha 410073 China

In this paper, a small flow rate hydrocarbon turbine pump was used to pressurize the fuel supply system of scramjet engine. Some experiments were carried out to investigate the characteristics of turbine pump driven by nitrogen or combustion gas under different operating conditions. A experimental database with regard to the curves of the rotational speed, mass flow rate and net head with regard to centrifugal pump were plotted. These curves were represented as functions of the pressure and temperature at turbine inlet/outlet and the throttle diameter at downstream of centrifugal pump. A sensitivity study has been carried out based on design of experiments. The experimental was employed to analyze net head of centrifugal and throttle characteristics. The research results can accumulate foundations for the close loop control system of turbine pump.

关键词： expansion cycle scram jet hydrocarbon fuel turbo-pump operation performance

Follicular lymphoma with cardiac involvement in a 90-year-old patient:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10208-10213页

作者： yi-xuan Sun Jia Wang Ji-Heng Zhu Wei Yuan Lin wu Department of Geriatrics Zhongshan HospitalFudan UniversityShanghai 200032China Department of Pathology Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND The incidence of cardiac lymphoma is low,and it mainly occurs secondary to nonHodgkin’s lymphoma,particularly diffuse large B-cell ***,we report a case of follicular lymphoma with cardiac involvement and severe heart failure as the sole clinical *** SUMMARY A 90-year-old male patient was first admitted to our hospital due to an accidentally discovered painless mass in the right lower abdomen.A biopsy of the mass revealed a follicular *** emission tomography-computed tomography confirmed mild pericardial effusion,and echocardiography showed no structural abnormalities with normal ejection fraction at the time of *** patient refused our recommendation of chemotherapy and was re-admitted 4 mo later due to heart failure.A series of subsequent echocardiographic examinations showed thickening of the left ventricular walls and increasing pericardial effusion over the following 2 *** heart failure exacerbated despite all symptomatic and supportive *** passed away after an episode of aspiration *** The diagnosis of cardiac lymphoma is difficult as its clinical manifestations are nonspecific,and prognosis is poor.

关键词： Follicular lymphoma Cardiac lymphoma Chemotherapy Heart failure Elderly patient Case report

Etomidate affects the anti-oxidant pathway to protect retinal ganglion cells after optic nerve transection

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Neural Regeneration Research 2019年第11期14卷 2020-2024页

作者： xuan Zhao Fang Kuang yi-Yan You Ming-Mei wu Si-Wei You Department of Neurobiology and Collaborative Innovation Center for Brain Science Air Force Medical UniversityXi'anShaanxi ProvinceChina Department of Histology and Embryology & Shaanxi Key Laboratory of Brain Disorders Xi'an Medical UniversityXi'anShaanxi ProvinceChina Ernest Mario School of Pharmacy Rutgersthe State University of New JerseyPiscatawayNJUSA

Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018.

关键词： nerve regeneration etomidate retinal ganglion cells optic nerve transection anti-oxidative stress nitric oxide malonaldehyde glutathione neural regeneration

Rectangle Attack Against Type-I Generalized Feistel Structures

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Chinese Journal of Electronics 2022年第4期31卷 713-720页

作者： ZHANG yi LIU Guoqiang SHEN xuan LI Chao College of Liberal Arts and Sciences National University of Defense Technology Hunan Engineering Research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences College of Information and Communication National University of Defense Technology

Type-I generalized Feistel networks(GFN) are widely used frameworks in symmetric-key primitive designs such as CAST-256 and Lesamnta. Different from the extensive studies focusing on specific block cipher instances, the analysis against Type-I GFN structures gives generic security evaluation of the basic frameworks and concentrates more on the effect of linear transformation. Currently, works in this field mainly evaluate the security against impossible differential attack,zero-correlation linear attack, meet-in-the-middle attack and yoyo game attack, while its security evaluation against rectangle attack is still missing. In this paper, we filled this gap and gave the first structural analytical results of Type-I GFN against rectangle attack. By exploiting its structural properties, we proved there exists a boomerang switch for Type-I GFN for the first time,which is independent of the round functions. Then we turned the boomerang switch into chosen plaintext setting and proposed a new rectangle attack model. By appending 1 more round in the beginning of the boomerang switch, we constructed a rectangle distinguisher and a key recovery attack could be performed.

关键词： Block cipher structures Rectangle attack Boomerang switch Structural attack Generalized Feistel networks

Vitrectomy with internal limiting membrane peeling versus its flap insertion for macular hole in high myopia: a Meta-analysis

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International Journal of Ophthalmology(English edition) 2020年第1期13卷 141-148页

作者： Ya-Jun wu Jie Rao Kang-Rui wu Na wu yi Cheng Xiao-xuan Xu Li Yan yi Shao Yu Tian Xiao-Rong wu Department of Ophthalmology the First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Ophthalmology the Second Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina

AIM: To compare the anatomic and functional outcomes between vitrectomy with internal limiting membrane(ILM) peeling and internal ILM flap insertion technique for high myopia macular hole(MH).METHODS: Pub Med, Cochrane Library, EMBASE, and CNKI were systematically searched, and all studies involved MH were included. The closure rate of MH and the postoperative best-corrected visual acuity(BCVA) at 6 mo after the initial surgery were the primary measures. All statistical tests were performed in Review Manager ***: Five studies that included 151 eyes of 151 patients were finally included, all of which were retrospectively comparative studies. Between the pars plana vitrectomy(PPV) with ILM peeling surgery and the ILM insertion technique, the latter had significantly better efficacy with respect to the closure rate of MH(OR=21.32, 95%CI=7.25-62.67, P<0.001);However, regarding BCVA at 6 mo after the initial surgery in MH, there was no statistical significance between the groups(OR=-0.04, 95%CI=-0.22-0.14, P=0.66). In addition, regarding the rate of retinal reattachment after the initial surgery, the two different methods were not significantly different(OR=2.22, 95%CI=0.34-14.32, P=0.4).CONCLUSION: Both ILM peeling and ILM insertion technique could significantly improve anatomic outcomes of MH in high myopia with or without retinal detachment(RD), and anatomic outcomes are more effective. However, there is no statistical significance in BCVA at 6 mo after the initial surgery in MH, or in the rate of retinal reattachment after the first surgery, between the two methods.

关键词： macular hole high myopia best-corrected visual acuity retinal attachment Meta-analysis

Identifying candidate genes involved in trichome formation on carrot stems by transcriptome profiling and resequencing

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Journal of Integrative Agriculture 2022年第12期21卷 3589-3599页

作者： wu Zhe YANG xuan ZHAO Yu-xuan JIA Li College of Horticulture Shanxi Agricultural UniversityTaigu 030801P.R.China Key Laboratory of Genetic Improvement and Ecophysiology of Horticultural Crop of Anhui Province Institute of HorticultureAnhui Academy of Agricultural SciencesHefei 230001P.R.China

Trichomes are specialized structures developed from epidermal cells and can protect plants against biotic and abiotic *** cover carrots during the generative ***,the morphology of the carrot trichomes and candidate genes controlling the formation of trichomes are still *** study found that carrot trichomes were nonglandular and unbranched hairs distributed on the stem,leaf,petiole,pedicel,and seed of *** analysis of a trichome mutant with sparse and short trichomes(sst)and a wild type(wt)with long and dense trichomes on carrot stems was conducted.A total of 15396 genes containing nonsynonymous mutations in sst were obtained,including 42 trichomerelated *** also analyzed the transcriptome of the trichomes on secondary branches when these secondary branches were 10 cm long between wt and sst and obtained 6576 differentially expressed genes(DEGs),including 24 trichome-related ***-PCR validation exhibited three significantly up-regulated DEGs,20 significantly downregulated,and one with no *** considered both the resequencing and transcriptome sequencing analyses and found that 12 trichome-related genes that were grouped into five transcription factor families containing nonsynonymous mutations and significantly down-regulated in ***,these genes are potentially promising candidate genes whose nonsynonymous mutations and down-regulation may result in scarce and short trichomes mutation on carrot stems in sst.

关键词： carrot trichome resequencing transcriptome candidate genes