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Explicit Stationary Distribution of the(L,1)-reflecting Random Walk on the Half Line

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Acta Mathematica Sinica,English Series 2014年第3期30卷 371-388页

作者： Wen Ming HONG Ke ZHOU yi qiang q.zhao School of Mathematical Sciences & Laboratory of Mathematics and Complex Systems Beijing Normal University School of Mathematics and Statistics Carleton University

In this paper,we consider the（L,1） state-dependent reflecting random walk（RW） on the half line,which is an RW allowing jumps to the left at a maximal size L.For this model,we provide an explicit criterion for（positive） recurrence and an explicit expression for the stationary distribution.As an application,we prove the geometric tail asymptotic behavior of the stationary distribution under certain conditions.The main tool employed in the paper is the intrinsic branching structure within the（L,1）-random walk.

关键词： Random walk multi-type branching process recurrence positive recurrence stationarydistribution tail asymptotic

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-qiang Zhang qing-Lin Cheng Wei Sun yi zhao Zhi-Min Li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

Deformable Catalytic Material Derived from Mechanical Flexibility for Hydrogen Evolution Reaction

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Nano-Micro Letters 2024年第2期16卷 287-311页

作者： Fengshun Wang Lingbin Xie Ning Sun Ting Zhi Mengyang Zhang Yang Liu Zhongzhong Luo Lanhua yi qiang zhao Longlu Wang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts&Telecommunications(NJUPT)9 WenyuanNanjing 210023People’s Republic of China Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education School of ChemistryXiangtan UniversityXiangtan 411105People’s Republic of China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)&Institute of Flexible Electronics(Future Technology)Nanjing University of Posts&Telecommunications9 WenyuanNanjing 210023People’s Republic of China

Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.

关键词： Deformable catalytic material Micro-nanostructures evolution Mechanical flexibility Hydrogen evolution reaction

Performance of the walking trail making test in older adults with white matter hyperintensities

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World Journal of Psychiatry 2024年第1期14卷 102-110页

作者： Hong-yi zhao Zhi-qiang Zhang Yong-Hua Huang Hong Li Fang-Yuan Wei Department of Neurology No.984 Hospital of PLABeijing 100094China Department of Neurology The Seventh Medical Center of PLA General HospitalBeijing 100700China Mental Health Institute of Inner Mongolia Autonomous Region The Third Hospital of Inner Mongolia Autonomous RegionHohhot 010010Inner Mongolia Autonomous RegionChina Department of Neurosurgery No.984 Hospital of PLABeijing 100094China Department of Hand and Foot Surgery Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Engineering Research Center of Chinese Orthopaedic and Sports Rehabilitation Artificial Intelligent Ministry of EducationBeijing 100029China

BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053

关键词： White matter hyperintensities Cognitive dysfunction Motor deficits Gait analysis Trail making test Small vessel disease

Automatic detection of small bowel lesions with different bleeding risks based on deep learning models

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World Journal of Gastroenterology 2024年第2期30卷 170-183页

作者： Rui-Ya Zhang Peng-Peng qiang Ling-Jun Cai Tao Li Yan qin Yu Zhang yi-qing zhao Jun-Ping Wang Department of Gastroenterology The Fifth Clinical Medical College of Shanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina School of Computer and Information Technology Shanxi UniversityTaiyuan 030006Shanxi ProvinceChina School of Life Sciences and Technology Mudanjiang Normal UniversityMudanjiang 157011Heilongjiang ProvinceChina

BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.

关键词： Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk

The infection kinetics and transmission potential of two Guaico Culex viruses in Culex quinquefasciatus mosquitoes

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Virologica Sinica 2024年第2期39卷 228-234页

作者： Ru-yi Chen Teng zhao Jing-Jing Guo Feng Zhu Na-Na Zhang Xiao-Feng Li Hai-Tao Liu Fei Wang Yong-qiang Deng Cheng-Feng qin College of Bioscience and Bioengineering Jiangxi Agricultural UniversityNanchang330045China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMSBeijing100071China School of Life Sciences Southwest Forestry UniversityKunming650224China

Guaico Culex virus(GCXV)is a newly identified segmented Jingmenvirus from Culex spp.mosquitoes in Central and South America.The genome of GCXV is composed of four or five single-stranded positive RNA segments.However,the infection kinetics and transmission capability of GCXV in mosquitoes remain unknown.In this study,we used reverse genetics to rescue two GCXVs(4S and 5S)that contained four and five RNA segments,respectively,in C6/36 cells.Further in vitro characterization revealed that the two GCXVs exhibited comparable replication kinetics,protein expression and viral titers.Importantly,GCXV RNAs were detected in the bodies,salivary glands,midguts and ovaries of Culex quinquefasciatus at 4–10 days after oral infection.In addition,two GCXVs can colonize Cx.quinquefasciatus eggs,resulting in positive rates of 15%–35%for the second gonotrophic cycle.In conclusion,our results demonstrated that GCXVs with four or five RNA segments can be detected in Cx.quinquefasciatus eggs during the first and second gonotrophic cycles after oral infection.

关键词： Guaico Culex virus(GCXV) Jingmenvirus Culex quinquefasciatus Vertical transmission

Protein neddylation and its role in health and diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1869-1904页

作者： Shizhen Zhang qing Yu Zhijian Li Yongchao zhao yi Sun Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Institute of Translational Medicine Zhejiang University School of MedicineHangzhou 310029China Department of Thyroid Surgery Zhejiang Cancer HospitalInstitute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhou 310022China Key Laboratory of Head&Neck Cancer Translational Research of Zhejiang Province Hangzhou 310022China Department of Hepatobiliary and Pancreatic Surgery Zhejiang University School of MedicineHangzhou 310029China Zhejiang Provincial Key Laboratory of Pancreatic Disease The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Zhejiang University Cancer Center Hangzhou 310029China Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Hangzhou 310024China Research Center for Life Science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China

NEDD8(Neural precursor cell expressed developmentally downregulated protein 8)is an ubiquitin-like protein that is covalently attached to a lysine residue of a protein substrate through a process known as neddylation,catalyzed by the enzyme cascade,namely NEDD8 activating enzyme(E1),NEDD8 conjugating enzyme(E2),and NEDD8 ligase(E3).The substrates of neddylation are categorized into cullins and non-cullin proteins.Neddylation of cullins activates CRLs(cullin RING ligases),the largest family of E3 ligases,whereas neddylation of non-cullin substrates alters their stability and activity,as well as subcellular localization.Significantly,the neddylation pathway and/or many neddylation substrates are abnormally activated or over-expressed in various human diseases,such as metabolic disorders,liver dysfunction,neurodegenerative disorders,and cancers,among others.Thus,targeting neddylation becomes an attractive strategy for the treatment of these diseases.In this review,we first provide a general introduction on the neddylation cascade,its biochemical process and regulation,and the crystal structures of neddylation enzymes in complex with cullin substrates;then discuss how neddylation governs various key biological processes via the modification of cullins and non-cullin substrates.We further review the literature data on dysregulated neddylation in several human diseases,particularly cancer,followed by an outline of current efforts in the discovery of small molecule inhibitors of neddylation as a promising therapeutic approach.Finally,few perspectives were proposed for extensive future investigations.

关键词： NEDD8 attached attractive

Rapid development of double-hit mRNA antibody cocktail against orthopoxviruses

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1768-1776页

作者： Hang Chi Suo-qun zhao Ru-yi Chen Xing-Xing Suo Rong-Rong Zhang Wen-Hui Yang Dong-Sheng Zhou Min Fang Bo ying Yong-qiang Deng Cheng-Feng qin State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMS100071BeijingChina College of Life Sciences Inner Mongolia Agricultural UniversityHohhot010018Inner MongoliaChina School of Life Sciences Henan UniversityKaifeng475004HenanChina Suzhou Abogen Biosciences Co. LtdSuzhou215123JiangsuChina Research Unit of Discovery and Tracing of Natural Focus Diseases Chinese Academy of Medical Sciences100071BeijingChina

The Orthopoxvirus genus,especially variola virus(VARV),monkeypox virus(MPXV),remains a significant public health threat worldwide.The development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing processes.mRNA-encoded antibodies have emerged as a powerful and universal platform for rapid antibody production.Herein,by using the established lipid nanoparticle(LNP)-encapsulated mRNA platform,we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against orthopoxviruses.In vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing antibodies.More importantly,mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus(VACV)lethal challenge mouse model,and a unique mRNA antibody cocktail,Mix2a,exhibited superior in vivo protection by targeting both intracellular mature virus(IMV)-form and extracellular enveloped virus(EEV)-form viruses.In summary,our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform,highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as otheremerging viruses.

关键词： proof universal neutral

Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 20 MeV on the Back-n at CSNS

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Nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： Jie-Ming Xue Song Feng Yong-Hao Chen Han yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu yi-Wei Yang Zi-Jie Han Da-Jun zhao Hao-qiang Wang Bao-qian Li Ji-Rong zhao Lei-Xun Tang Wen Luo Bo Zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron Source.Neutron energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission measurements.The on-beam background was determined using Co,In,Ag,and Cd filters.The excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling program.The present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation curve.Good agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding region.This measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy range.This provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline