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Robust Space-Time Adaptive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum

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Journal of Beijing Institute of Technology 2024年第1期33卷 65-74页

作者： Xiaojing Su da xu Dongsheng Zhu Zhixun Ma Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak ***,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the *** this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and *** simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities.

关键词： space-time adaptive detection track before detect robustness persymmetric property symmetric spectrum AMF test RAO test

Local search yields a PTAS for fixed-dimensional k-means problem with penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 351-362页

作者： Fan Yuan da-Chuan xu Dong-Lei Du Dong-Mei Zhang Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Management University of New BrunswickFrederictonNB E3B 9Y2Canada School of Computer Science and Technology Shandong Jianzhu UniversityJinan 250101ShandongChina

We study a problem called the k-means problem with penalties(k-MPWP),which is a natural generalization of the typical k-means *** this problem,we have a set D of client points in R^(d),a set F of possible centers in R^(d),and a penalty cost Pj>O for each point j∈*** are also given an integer k which is the size of the center point *** want to find a center point set S■F with size k,choose a penalized subset of clients P■D,and assign every client in D\P to its open *** goal is to minimize the sum of the squared distances between every point in D\P to its assigned centre point and the sum of the penalty costs for all clients in *** using the multi-swap local search technique and under the fixed-dimensional Euclidean space setting,we present a polynomial-time approximation scheme(PTAS)for the k-MPWP.

关键词： Approximation algorithm k-means Local search Penalty

From Acupoints to Mylohyoid: Revealing the Neural Circuitry Basis of Electroacupuncture for Dysphagia

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Neuroscience Bulletin 2024年第1期40卷 139-142页

作者： Xiaoli da xuhong Jiang Lihong Li Cenglin xu Zhong Chen Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhou 310053China Department of Neurology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310003China Department of Acupuncture the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310000China

Acupuncturea representative and historical treatment in traditional Chinese medicine(TCM),has been used to cure diseases for Chinese people in the past *** the late 1990s,acupuncture has been further accepted *** World Health Organization(WHO)proposed Clinical Research Specification for acupuncture in 1995 and the US Food and Drug Administration(Fda)approved acupuncture as a complementary and alternative therapy for various kinds of diseases in 1996,with clinical advantages such as convenience and effectiveness[1].Cumulative evidence has proved that acupuncture could produce different degrees of efficacy for treating various kinds of diseases(such as neuropathic pain,migraine,Parkinson's disease et al.)and alleviate symptoms[2-4].However,unlike its evidence-based efficacies.

关键词： medicine(TCM) acupuncture Acupuncture

Hydrodynamic resistance of pore–throat structures and its effect on shale oil apparent permeability

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International Journal of Coal Science & Technology 2024年第2期11卷 101-110页

作者： Wendong Wang Qian Zhang Jilong xu da Zheng Lifeng Liu Yuliang Su Key Laboratory of Unconventional Oil and Gas Development Ministry of EducationQingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Oil Gas and New Energies CompanyBeijing 100083China Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China

Oil transport is greatly affected by heterogeneous pore–throat structures present in *** is therefore very important to accurately characterize pore–throat ***,it remains unclear how pore–throat structures affect oil transport *** this paper,using finite element(FE)simulation and mathematical modeling,we calculated the hydrodynamic resistance for four pore–throat *** addition,the influence of pore throat structure on shale oil permeability is *** to the results,the hydrodynamic resistance of different pore throat structures can vary by 300%.The contribution of additional resistance caused by streamline bending is also in excess of 40%,even without slip ***-thermore,Pore–throat structures can affect apparent permeability by more than 60%on the REV scale,and this influence increases with heterogeneity of pore size distribution,organic matter content,and organic matter ***,modeling shale oil flow requires consideration of porous–throat structure and additional resistance,otherwise oil recovery and flow capacity may be overestimated.

关键词： Pore–throat structure Hydrodynamic resistance Apparent permeability REV-scale Shale oil

Satellite glial cells in sensory ganglia play a wider role in chronic pain via multiple mechanisms

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Neural Regeneration Research 2024年第5期19卷 1056-1063页

作者： Xiaoyun Qiu Yuanzhi Yang Xiaoli da Yi Wang Zhong Chen Cenglin xu Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina

Satellite glial cells are unique glial cells that surround the cell body of primary sensory *** increasing body of evidence suggests that in the presence of inflammation and nerve damage,a significant number of satellite glial cells become activated,thus triggering a series of functional *** suggests that satellite glial cells are closely related to the occurrence of chronic *** this review,we first summarize the morphological structure,molecular markers,and physiological functions of satellite glial ***,we clarify the multiple key roles of satellite glial cells in chronic pain,including gap junction hemichannel Cx43,membrane channel Pannexin1,K channel subunit 4.1,ATP,purinergic P2 receptors,and a series of additional factors and their receptors,including tumor necrosis factor,glutamate,endothelin,and ***,we propose that future research should focus on the specific sorting of satellite glial cells,and identify genomic differences between physiological and pathological *** review provides an important perspective for clarifying mechanisms underlying the peripheral regulation of chronic pain and will facilitate the formulation of new treatment plans for chronic pain.

关键词： chronic pain primary sensory neurons satellite glial cells sensory ganglia

Cancer organoids:A platform in basic and translational research

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Genes & Diseases 2024年第2期11卷 614-632页

作者： Xin Ma Qin Wang Guozheng Li Hui Li Shouping xu da Pang Department of Breast Surgery Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Sino-Russian Medical Research Center Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Heilongjiang Academy of Medical Sciences HarbinHeilongjiang 150086China Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China) College of Pharmacy of Harbin Medical UniversityHarbinHeilongjiang 150086China

An accumulation of previous work has established organoids as good preclinical models of human tumors,facilitating translation from basic research to clinical *** are changing the paradigm of preclinical cancer research because they can recapitulate the heterogeneity and pathophysiology of human cancers and more closely approximate the complex tissue environment and structure found in clinical tumors than in vitro cell lines and animal ***,the potential applications of cancer organoids remain to be comprehensively *** the review,we firstly describe what is currently known about cancer organoid culture and then discuss in depth the basic mechanisms,including tumorigenesis and tumor metastasis,and describe recent advances in patient-derived tumor organoids(PDOs)for drug screening and immunological ***,the present challenges faced by organoid technology in clinical practice and its prospects are *** review highlights that organoids may offer a novel therapeutic strategy for cancer research.

关键词： Drug assays Immunotherapy Mechanism research Organoids Precision medicine

Multiple damage zones around hydraulic fractures generated by high-frequency pulsating hydraulic fracturing

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Petroleum Science 2024年第4期21卷 2688-2702页

作者： Yan Peng Sheng-Jie Wei Guang-Qing Zhang da-Wei Zhou Chuang-chao xu School of Petroleum Engineering China University of Petroleum PetroChina changqing Oilfield Company

Pulsating hydraulic fracturing(PHF) is a promising fracturing method and can generate a dynamic periodic pressure. The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture. If the frequency of periodic pressure exceeds 10 Hz, the distribution of pressure along the main fracture will be heterogeneous, which is much different from the one induced by the common fracturing method. In this study, the impact of this special spatial feature of pressure on hydraulic fracture is mainly investigated. A coupled numerical simulation model is first proposed and verified through experimental and theoretical solutions. The mechanism of secondary fracture initiation around the main fracture is then discovered. In addition, sensitivity studies are conducted to find out the application potential of this new method. The results show that(1) this coupled numerical simulation model is accurate. Through comparison with experimental and theoretical data, the average error of this coupled model is less than 1.01%.(2) Even if a reservoir has no natural fracture, this heterogeneous distribution pressure can also cause many secondary fractures around the main fracture.(3) The mechanism of secondary fracture initiation is that this heterogeneous distribution pressure causes tensile stress at many locations along the main fracture.(4) Through adjusting the stimulation parameters, the stimulation efficiency can be improved. The average and amplitude of pressure can increase possibility of secondary fracture initiation. The frequency of this periodic pressure can increase number of secondary fractures. Even 6 secondary fractures along a 100 m-length main fracture can be generated.(5) The influence magnitudes of stimulation parameters are larger than ones of geomechanical properties, therefore, this new fracturing method has a wide application potential.

关键词： Tight reservoir Reservoir stimulation Numerical simulation Secondary fracture Fracture initiation

Sulfation of chondroitin and bile acids converges to antagonize Wnt/β-catenin signaling and inhibit APC deficiency-induced gut tumorigenesis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1241-1256页

作者： Pengfei xu Yue Xi Jong-Won Kim Junjie Zhu Min Zhang Meishu xu Songrong Ren da Yang Xiaochao Ma Wen Xie Center for Pharmacogenetics and Department of Pharmaceutical Sciences University of PittsburghPittsburghPA 15261USA Department of Hepatobiliary and Pancreatic Surgery Zhongnan Hospital of Wuhan UniversitySchool of Pharmaceutical SciencesWuhan UniversityWuhan 430071China Department of Pharmacology&Chemical Biology University of PittsburghPittsburghPA 15261USA

Sulfation is a crucial and prevalent conjugation reaction involved in cellular processes and mammalian physiology.3’-Phosphoadenosine 5’-phosphosulfate(PAPS)synthase 2(PAPSS2)is the primary enzyme to generate the universal sulfonate donor *** involvement of PAPSS2-mediated sulfation in adenomatous polyposis coli(APC)mutation-promoted colonic carcinogenesis has not been ***,we showed that the expression of PAPSS2 was decreased in human colon tumors along with cancer stages,and the lower expression of PAPSS2 was correlated with poor prognosis in advanced colon *** epithelial-specific heterozygous Apc deficient and Papss2-knockout(Apc^(Δgut-Het)Papss2^(Δgut))mice were created,and the phenotypes were compared to the spontaneous intestinal tumorigenesis of Apc^(Δgut-Het)***^(Δgut-Het)Papss2^(Δgutmice) were more sensitive to gut tumorigenesis,which was mechanistically accounted for by the activation of Wnt/β-catenin signaling pathway due to the suppression of chondroitin sulfation and inhibition of the farnesoid X receptor(FXR)-transducin-like enhancer of split 3(TLE3)gene regulatory *** sulfate supplementation in Apc^(Δgut-Het)Papss2^(Δgutmice) alleviated intestinal *** summary,we have uncovered the protective role of PAPSS2-mediated chondroitin sulfation and bile acids-FXR-TLE3 activation in the prevention of gut carcinogenesis via the antagonization of Wnt/β-catenin *** sulfate may be explored as a therapeutic agent for Papss2 deficiency-associated colonic carcinogenesis.

关键词： Colon cancer APC Wnt/b-catenin PAPSS2 Chondroitin sulfate Sulfation Bile acids FXR

Hierarchical Voronoi Structure Inspired by Cat Paw Pads Substantially Enhances Landing Impact Energy Dissipation

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Journal of Bionic Engineering 2024年第4期21卷 1847-1861页

作者： da Lu Baoqing Pei Yangyang xu Mengyuan Hu Shijia Zhang Le Zhang Xin Huang Yangwei Wang xueqing Wu Beijing Key Laboratory for Design and Evaluation Technology of Advanced Implantable&Interventional Medical Devices Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang University100083BeijingChina National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology100081BeijingChina Shenzhen Institute of Beihang University 518000ShenzhenChina

When a human lands from a high drop,there is a high risk of serious injury to the lower *** the other hand,cats can withstand jumps and falls from heights without being fatally wounded,largely due to their impact-resistant paw *** aim of the present study was to investigate the biomechanism of impact resistance in cat paw pads,propose an optimal hierarchical Voronoi structure inspired by the paw pads,and apply the structure to bionic cushioning shoes to reduce the impact force of landing for *** microstructure of cat paw pads was observed via tissue section staining,and a simulation model was reconstructed based on CT to verify and optimize the structural cushioning *** distribution pattern,wall thickness of compartments,thickness ratio of epidermis and dermis,and number of compartments in the model were changed and simulated to achieve an optimal composed structure.A bionic sole was 3D-printed,and its performance was evaluated via compression test and a jumping-landing *** results show that cat paw pads are a spherical cap structure,divided from the outside to the inside into the epidermis,dermis,and compartments,each with different cushioning capacities.A finite element simulation of different cushioning structures was conducted in a cylinder with a diameter of 20 mm and a height of 10 mm,featuring a three-layer *** optimal configuration of the three layers should have a uniform distribution with 0.3–0.5 mm wall thickness,a 1:1–2 thickness ratio of epidermis and dermis,and 100–150 compartments.A bionic sole with an optimized structure can reduce the peak impact force and delay the peak arrival *** energy absorption rate is about 4 times that of standard *** jumping 80,100,and 120 cm,the normalized ground reaction force is also reduced by 8.7%,12.6%and 15.1%compared with standard *** study provides theoretical and technical support for effective protection against human lower limb landing injuries.

关键词： Cat paw pads Hierarchical Voronoi structure Landing impact Energy dissipation Bionic sole