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Crown-Like Baffle System against Rock Avalanches:Energy Dissipation Mechanism and Numerical Verification

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Journal of Earth Science 2023年第2期34卷 304-315页

作者： Yu Huang Hao Shi Bei Zhang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai 200092China

In mountainous areas,rock avalanches swarm downslope leading to large impact forces on structures.Baffle systems are usually set up in torrent channels to dissipate the flow energy and reduce the destructive effects.In this paper,a crown-like baffle system is proposed to better dissipate the flow energy.The energy dissipation mechanism of this system was investigated based on DEM.The results reveal more than 90%of the kinetic energy of the granular flow was dissipated by particleparticle interaction.Two effects,the impedance effect and the deflection effect,were identified.The influence of these effects leads to the formation and growth of cushions behind the baffles,and these cushions enhance the particle-particle interaction.Two crown-like baffle systems were compared with a conventional baffle system based on the typical avalanche model.The results reveal the cumulative residual kinetic energy of the crown-like baffle system with square baffles decreased by 18.75%with the same concrete consumption as the conventional baffle system.For the crown-like baffle system with triangular baffles,the cumulative residual kinetic energy decreased by 6.22%with 83.94%of the concrete consumption of the conventional baffle system.Hence,the proposed baffle system is more cost-effective compared with the conventional baffle system.

关键词： rock avalanches new baffle system energy dissipation discrete element method engineering geology

Effect of the same mechanical loading on osteogenesis and osteoclastogenesis in vitro

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Chinese Journal of Traumatology 2015年第3期18卷 150-156页

作者： Yong Guo Yang Wang Yinqin Liu Haitao Wang Chun Guo Xizheng zhang Chaoyong bei College ofBioteehnology Guilin Medical University Guilin 541004 China Department of Medicine Luohe Medical College Luohe 462000 China Institute of Medical Equipment Academy of Military Medical Sciences Tianjin 300161 China Department of Orthopedic Affiliated Hospital of Guilin Medical University. Guilin 541000 China

Purpose: To investigate the influence of the same mechanical loading on osteogenesis and osteoclastogenesis in vitro . Methods: Primary osteoblasts, bone marrow-derived mesenchymal stem cells (BMSCs, cultured in osteoinductive medium) and RAW264.7 cells cultured in osteoclast inductive medium were all subjected to a 1000 μstrain (μs) at 1 Hz cyclic mechanical stretch for 30 min (twice a day). Results: After mechanical stimulation, the alkaline phosphatase (ALP) activity, osteocalcin protein level of the osteoblasts and BMSCs were all enhanced, and the mRNA levels of ALP and collagen type I increased. Additionally, extracellular-deposited calcium of both osteoblasts and BMSCs increased. At the same time, the activity of secreted tartrate-resistant acid phosphatase, the number of tartrate-resistant acid phosphatase-positive multinucleated cells, matrix metalloproteinase-9 protein levels of RAW264.7 cells and the extracellular calcium solvency all decreased. Conclusion: The results demonstrated that 1000 μs cyclic mechanical loading enhanced osteoblasts activity, promoted osteoblastic differentiation of BMSCs and restrained osteoclastogenesis of RAW264.7 cells in vitro .

关键词：成骨细胞分化破骨细胞体外培养机械负荷 RAW264.7细胞骨髓间充质干细胞基质金属蛋白酶-9 骨髓基质干细胞

Therapeutic potential of natural compounds from Chinese medicine in acute and subacute phases of ischemic stroke

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Neural Regeneration Research 2020年第3期15卷 416-424页

作者： Bei Zhang Kathryn ESaatman Lei Chen College of Public Health Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina Spinal Cord and Brain Injury Research Center Department of PhysiologyUniversity of KentuckyKYUSA

Stroke is one of the leading causes of death and disability in adults worldwide,resulting in huge social and financial burdens.Extracts from herbs,especially those used in Chinese medicine,have emerged as new pharmaceuticals for stroke treatment.Here we review the evidence from preclinical studies investigating neuroprotective properties of Chinese medicinal compounds through their application in acute and subacute phases of ischemic stroke,and highlight potential mechanisms underlying their therapeutic effects.It is noteworthy that many herbal compounds have been shown to target multiple mechanisms and in combinations may exert synergistic effects on signaling pathways,thereby attenuating multiple aspects of ischemic pathology.We conclude the paper with a general discussion of the prospects for novel natural compound-based regimens against stroke.

关键词： cell death herbal compound immune response ischemic stroke therapy neuroplasticity neuroprotection oxidative damage traditional Chinese medicine

STABILIZED NONCONFORMING MIXED FINITE ELEMENT METHOD FOR LINEAR ELASTICITY ON RECTANGULAR OR CUBIC MESHES

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Journal of Computational Mathematics 2022年第6期40卷 865-881页

作者： Bei Zhang Jikun Zhao Minghao Li Hongru Chen School of Sciences Henan University of TechnologyZhengzhou 450001China School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Based on the primal mixed variational formulation,a stabilized nonconforming mixed finite element method is proposed for the linear elasticity on rectangular and cubic meshes.Two kinds of penalty terms are introduced in the stabilized mixed formulation,which are the jump penalty term for the displacement and the divergence penalty term for the stress.We use the classical nonconforming rectangular and cubic elements for the displacement and the discontinuous piecewise polynomial space for the stress,where the discrete space for stress are carefully chosen to guarantee the well-posedness of discrete formulation.The stabilized mixed method is locking-free.The optimal convergence order is derived in the L^(2)-norm for stress and in the broken H^(1)-norm and L^(2)-norm for displacement.A numerical test is carried out to verify the optimal convergence of the stabilized method.

关键词： Mixed finite element method Nonconforming rectangular or cubic elements Elasticity Locking-free Stabilization

A Mixed Formulation of Stabilized Nonconforming Finite Element Method for Linear Elasticity

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Advances in Applied Mathematics and Mechanics 2020年第1期12卷 278-300页

作者： Bei Zhang Jikun Zhao College of Science Henan University of TechnologyZhengzhouHenan 450001China School of Mathematics and Statistics Zhengzhou UniversityZhengzhouHenan 450001China

Based on the primal mixed variational formulation,a stabilized nonconforming mixed finite element method is proposed for the linear elasticity problem by adding the jump penalty term for the displacement.Here we use the piecewise constant space for stress and the Crouzeix-Raviart element space for displacement.The mixed method is locking-free,i.e.,the convergence does not deteriorate in the nearly incompressible or incompressible case.The optimal convergence order is shown in the L^(2)-norm for stress and in the broken H1-norm and L2-norm for displacement,respectively.Finally,some numerical results are given to demonstrate the optimal convergence and stability of the mixed method.

关键词： Mixed method nonconforming finite element elasticity locking-free stabilization

Migration and fate of polycyclic aromatic hydrocarbons in bioretention systems with different media:experiments and simulations

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 17-33页

作者： Zhaoxin zhang Jiake Li Zhe Liu Yajiao Li Bei Zhang Chunbo Jiang Institute of Land Engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi’an University of TechnologyXi’an 710048China School of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an 710054China College of Landscape Architecture and Art Northwest A&F UniversityYangling 712100China

Polycyclic aromatic hydrocarbons(PAHs)present significant risks to human health owing to their carcinogenic,teratogenic,and mutagenic properties.The contamination of surface water with PAHs via runoff has become a prominent source of water pollution.While the capacity of bioretention systems to remove PAHs from runoff is recognized,the dynamics of PAH migration and degradation in these systems are not well-understood.This study aims to explain the migration and fate of PAHs in bioretention systems through a series of experiments and model simulations.This study constructed bioretention systems with three different media types and found that these systems achieved PAH load reductions exceeding 92%.Notably,naphthalene(NAP),fluoranthene(FLT),and pyrene(PYR)tended to accumulate in the media’s upper layer,at depths of 10 to 40 cm.To further analyze the migration and fate of PAHs during multi-site rainfall events and across prolonged operation,we applied the HYDRUS-1D model under three distinct scenarios.The findings of this study indicated that NAP degraded in 40 d,whereas FLT and PYR showed incomplete degradation after 120 d.During continuous rainfall events,there was no clear pattern of PAH accumulation;however,FLT and PYR persisted in the bioretention systems.The combination of experimental and simulation findings highlights the inevitable accumulation of PAHs during extended use of bioretention systems.This research provides a theoretical basis for improving operational efficiency,advancing PAH degradation in bioretention systems,and reducing their toxicity.

关键词： Bioretention Polycyclic aromatic hydrocarbons HYDRUS-1D Model simulation Migration

Association between homologous recombination deficiency and outcomes with platinum and platinum-free chemotherapy in patients with triple-negative breast cancer

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Cancer Biology & Medicine 2023年第2期20卷 155-168页

作者： Yimeng Chen Xue Wang Feng Du Jian Yue Yiran Si Xiaochen Zhao Lina Cui Bei Zhang Ting bei Binghe Xu Peng Yuan Department of Medical Oncology and Clinical Trial Center National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of VIP Medical Services National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China The Medical Department 3D Medicines Inc.Shanghai 201114China

Objective:The choice of chemotherapeutic regimen for triple-negative breast cancer(TNBC)remains controversial.Homologous recombination deficiency(HRD)has attracted increasing attention in informing chemotherapy treatment.This study was aimed at investigating the feasibility of HRD as a clinically actionable biomarker for platinum-containing and platinum-free therapy.Methods:Chinese patients with TNBC who received chemotherapy between May 1,2008 and March 31,2020 were retrospectively analyzed with a customized 3D-HRD panel.HRD positivity was defined by an HRD score≥30 or deleterious BRCA1/2 mutation.A total of 386 chemotherapy-treated patients with TNBC were screened from a surgical cohort(NCT01150513)and a metastatic cohort,and 189 patients with available clinical and tumor sequencing data were included.Results:In the entire cohort,49.2%(93/189)of patients were identified as HRD positive(40 with deleterious BRCA1/2 mutations and 53 with BRCA1/2 intact with an HRD score of≥30).In the first-line metastatic setting,platinum therapy was associated with longer median progression-free survival(mPFS)than platinum-free therapy[9.1 vs.3.0 months;hazard ratio(HR),0.43;95%confidence interval 0.22–0.84;P=0.01].Among HRD-positive patients,the mPFS was significantly longer in those treated with platinum rather than platinum-free therapy(13.6 vs.2.0 months;HR,0.11;P=0.001).Among patients administered a platinum-free regimen,HRD-negative patients showed a PFS significantly superior to that of HRD-positive patients(P=0.02;treatment-biomarker P-interaction=0.001).Similar results were observed in the BRCA1/2-intact subset.In the adjuvant setting,HRD-positive patients tended to benefit more from platinum chemotherapy than from platinum-free chemotherapy(P=0.05,P-interaction=0.02).Conclusions:HRD characterization may guide decision-making regarding the use of platinum treatment in patients with TNBC in both adjuvant and metastatic settings.

关键词： Homologous recombination deficiency triple-negative breast cancer platinum survival BRCA

Notch signaling mediated by TGF-β/Smad pathway in concanavalin A-induced liver fibrosis in rats

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World Journal of Gastroenterology 2017年第13期23卷 2330-2336页

作者： Yi Wang Ruo-Wu Shen Bing Han Zhen Li Le Xiong Feng-Yu zhang bei-bei Cong Bei Zhang Department of Immunology Medical College of Qingdao University Department of Anatomy Medical College of Qingdao University Department of Hepatobiliary Surgery Affiliated Hospital of Qingdao University

AIM To explore the exact interaction between Notch and transforming growth factor(TGF)-β signaling in liver fibrosis. METHODS We established a rat model of liver fibrosis induced by concanavalin A. Peripheral blood mononuclear cells(PBMCs) were isolated from the modeled rats, and cultured with γ-secretase inhibitor DAPT and TGF-β inhibitor for 24 h. The m RNA levels of Notch and TGF-β signaling were detected by quantitative real-time polymerase chain reaction. Expression of Notch and TGF-β proteins was analyzed by western blotting.RESULTS Compared to control rats, Notch and TGF-β signaling was activated in PBMCs of model rats. Administration of DAPT and TGF-β inhibitor suppressed Notch and TGF-β signal transducer in PBMCs of model rats. DAPT reduced m RNA and protein expression of TGF-β signaling, such as TGF-β1 and Smad3. TGF-β inhibitor also downregulated Notch1, Hes1 and Hes5, and m RNA and protein expression of the Notch signaling pathway.CONCLUSION Notch and TGF-β signaling play a role in liver fibrosis. TGF-β signaling upregulates Notch signaling, which promotes TGF-β signaling.

关键词： Notch Peripheral blood mononuclear cells Concanavalin A Transforming growth factor-β Liver fibrosis

三腔间隙引流(TCC)可降低肛周脓肿术后肛瘘发生率:一项匹配病例对照研究

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Gastroenterology Report 2018年第3期6卷 221-224,I0003页

作者： Heiying Jin Yan Chen Bei Zhang Department of Colorectal Surgery The Second Affiliated Hospital of Nanjing University of Chinese MedicineNanjingChina Graduate School of Nanjing University of Chinese Medicine NanjingChina Department of Colorectal Surgery The Third Affiliated Hospital of Nanjing University of Chinese MedicineNanjingChina

目的:本研究目的旨在评估三腔间隙引流(TCC)治疗肛周脓肿的安全性和有效性。方法:收集2013年6月至2016年3月间在南京中医药大学附属第二和第三医院的肛周脓肿患者的病例资料,其中,46例患者接受了TCC治疗。按照性别、年龄、脓肿部位进行1... 详细信息

目的:本研究目的旨在评估三腔间隙引流(TCC)治疗肛周脓肿的安全性和有效性。方法:收集2013年6月至2016年3月间在南京中医药大学附属第二和第三医院的肛周脓肿患者的病例资料,其中,46例患者接受了TCC治疗。按照性别、年龄、脓肿部位进行1:1:1匹配,选取同期行单纯切开引流术的46例患者和行一期切开引流挂线术(根治性手术)的46例患者进行对比分析。比较三组患者的住院时间、切口愈合时间、肛瘘发生率及肿门失禁情况。结果:TCC组患者术后肛瘘发生率为13.0%,显著低于单纯切开引流组(39.1%,P0.05)。根治性脓肿切开组有2例患者术后出现肛门失禁、腹胀和污粪,其Wexner失禁评分分别为6分和3分;而TCC组和单纯切开引流组无肛门失禁发生。三组患者切口愈合时间和住院时间的差异均无统计学意义(均P>0.05)结论:TCC是一项安全有效的保留括约肌功能的肛周脓肿治疗术式,可降低脓肿引流术后肛瘘发生率。该术式有望在临床实践中推广应用,其临床疗效尚需进一步研究证实。

关键词：三腔间隙引流(TCC) 肛周脓肿肛瘘引流术挂线术