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Acta Mechanica Solida Sinica 2014年第3期27卷 306-314页

作者： Jun Wu Xinhua Yang fan bai Department of Mechanics Huazhong University of Science and Technology

According to the elastic-viscoelastic correspondence principle, an elastic microme- chanical framework taking the inclusion-matrix interface effect into account is extended for predicting viscoelastic properties of asphalt mixture, which is simply treated as elastic coarse aggregate inclusions periodically and isotropically embedded in a viscoelastic asphalt mastic matrix. The Burgers model is adopted for characterizing the matrix mechanical behavior, so that the homogenized relaxation modulus of asphalt mixture in compression creep is derived. After a series of uniaxial compression creep tests are performed on asphalt mastic in different temperature and stress conditions in order to determine the matrix constitutive parameters, the framework presented is validated by comparison with the experiment, and then some predictions of uniaxial compression creep behavior of asphalt mixture in different temperature and stress conditions are given.

关键词： asphalt mixture micromechanics elastic-viscoelastic correspondence principle compression creep

Cancer biology deciphered by single-cell transcriptomic sequencing

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Protein & Cell 2022年第3期13卷 167-179页

作者： Yanmeng Li Jianshi Jin fan bai Biomedical Pioneering Innovation Center(BIOPIC) School of Life SciencesPeking UniversityBeijing 100871China RIKEN Center for Biosystems Dynamics Research(BDR) 6-2-3FuruedaiSuitaOsakaJapan Beijing Advanced Innovation Center for Genomics(ICG) Peking UniversityBeijing 100871China

Tumors are complex ecosystems in which heterogeneous cancer cells interact with their microenvironment composed of diverse immune,endothelial,and stromal *** biology had been studied using bulk genomic and gene expression profiling,which however mask the cellular diversity and average the variability among individual molecular *** advances in single-cell transcriptomic sequencing have enabled a detailed dissection of tumor ecosystems and promoted our understanding of tumorigenesis at single-cell *** the present review,we discuss the main topics of recent cancer studies that have implemented singlecell RNA sequencing(scRNA-seq).To study cancer cells,scRNA-seq has provided novel insights into the cancer stem-cell model,treatment resistance,and cancer *** study the tumor microenvironment,scRNA-seq has portrayed the diverse cell types and complex cellular states of both immune and non-immune cells interacting with cancer cells,with the promise to discover novel targets for future immunotherapy.

关键词： single-cell transcriptomic sequencing tumor microenvironment cancer

Damage Evolution and Crack Propagation in Semicircular Bending Asphalt Mixture Specimens

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Acta Mechanica Solida Sinica 2016年第6期29卷 596-609页

作者： Guowei Zeng Xinhua Yang Long Chen fan bai School of Civil Engineering and Mechanics Huazhong University of Science and Technology School of Science Wuhan University of Science and Technology

The damage and fracture behaviors of semicircular bending （SCB） asphalt mixture specimens with different orientation notches are experimentally and numerically investigated. In the numerical simulations, asphalt mixture is modeled as a two-phase material, namely a mix of coarse aggregates and asphalt mastic, and the mechanical behavior of asphalt mastic is charac- terized with the damage constitutive model and the damage-based fracture criterion. Some SCB experiments are performed on the asphalt mixture specimens with different orientation notches to validate the numerical method. Finally, the effects of notch orientation and aggregate distrib- ution on crack path, damage distribution, and the load vs. displacement relation are numerically evaluated.

关键词： semicircular bending heterogeneous model damage notch orientation

Effect of two biogas residues' application on copper and zinc fractionation and release in different soils

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Journal of Environmental Sciences 2013年第9期25卷 1865-1873页

作者： Miao Chen Yanshan Cui fan bai Jiaojiao Wang College of Resources and Environment University of Chinese Academy of Sciences

Biogas residue （BR） is widely used as a new green fertilizer in agriculture in China. However, it often contains a high concentration of heavy metals so its application should cause our concern. An incubation experiment was conducted to study the risk of pig biogas residue （PBR） and chicken biogas residue （CBR） application on Liuminying soil （LS） and Yixing soil （YS）. The soils were incubated for one, three and six months with 0, 2%, 4% and 6% addition of BRs. According to BCR extraction results, the PBR and CBR applications induced an increase in the concentration of exchangeable fraction of Zn. As for the concentration of exchangeable fraction of Cu, an increase was only observed in the treatments with PBR application. The heavy metal binding intensity also showed a similar trend. With the PBR application, for the LS and YS, the highest concentrations of exchangeable Zn increased 3.6 and 9.5 times, respectively, while the exchangeable Cu was increased by 52.6% and 187.1%. Dissolved organic carbon was the limiting factor for the exchangeable Cu while the exchangeable Zn was controlled by soil pH. PBR presented more agricultural risk than CBR when used as fertilizer. Meanwhile, BRs were more adaptable to LS than YS according to the heavy metal release results.

关键词： biogas residue heavy metal soil incubation metal fractionation metal binding intensity

An Optimal Bit-Rate Allocation Algorithm to Improve Transmission Efficiency of Images in Deep Space Exploration

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China Communications 2020年第7期17卷 94-100页

作者： Yong Xu Jionghui Li Xiangyu Lin fan bai Beijing Institute of Spacecraft System Engineering Beijing100094

As fixed compression ratio is used in traditional deep space exploration image transmission application,the same compression code rate is allocated to each ***,since the information of each image in a space observation mission is nonuniform,the image with more information will inevitably lead to more compression distortion than the image with less ***,it’s not an efficient way to transmit information in terms of data importance or overall ***,we proposed a combinatorial optimal bit rate allocation algorithm to improve the efficiency of image transmission in space *** from traditional method,the rate-distortion model of wavelet coefficients for each image in a transmission task was built,and under the overall maximum transmission rate constraint,an bit-rate optimal allocation was applied for each image to minimize the overall distortion of a batch of *** proposed algorithm can be widely used in image compression algorithm with embedded code stream characteristics,such as JPEG2000 and *** results shows that in the range of 2.6 to 10 compression ratio,the algorithm can reduce image distortion MSB by 40%~64%at the same overall transmission code rate,which equivalent to improvement of PSNR 3 dB to 5.4 dB.

关键词： JPEG2000 Efficiency distortion

Experimental and numerical analyses of the effect of fibre content on the close-in blast performance of a UHPFRC beam

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Defence Technology（防务技术） 2024年第1期31卷 242-261页

作者： Junbo Yan Qiyue Zhang Yan Liu Yingliang Xu Zhenqing Shi fan bai Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)*** paper aims to address this knowledge gap through experimental and mesoscale numerical *** were conducted on ten UHPFRC beams built with varying steel fiber volumetric fractions subjected to close-in explosive ***,this study considered other parameters,such as the longitudinal reinforcement type and *** the case of UHPFRC beams featuring normal-strength longitudinal reinforcement of diametersΦ12,Φ16,andΦ20,a reduction in maximum displacement by magnitudes of19.6%,19.5%,and 17.4%was observed,respectively,as the volumetric fractions of fiber increased from1.0%to 2.5%.In addition,increasing the longitudinal reinforcement ratio and using high-strength steel longitudinal reinforcement both significantly reduced the deformation characteristics and increase the blasting resistances of UHPFRC ***,the effects on the local crushing and spalling damage were not significant.A mesoscale finite element model,which considers the impacts of fiber parameters on UHPFRC beam behaviors,was also established and well correlated with the test ***,parametric analyses were further conducted to examine the impacts of the steel fiber content and length and the hybrid effects of various types of microfibers and steel fibers on the blasting performance of UHPFRC beams.

关键词： Blast performance Close-in blast Fiber content Mesoscale approach UHPFRC beams

A quasi-isentropic model of a cylinder driven by aluminized explosives based on characteristic line analysis

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Defence Technology（防务技术） 2022年第11期18卷 1979-1999页

作者： Hong-fu Wang Yan Liu fan bai Jun-bo Yan Xu Li Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum(Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed,and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction(diffusion and kinetic) between the Al powder and the detonation products;the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.

关键词： Aluminized explosives Cylinder experiments Quasi-isentropic model Characteristic line analysis Reaction degree of Al powder Physical parameters of detonation products

A race to uncover a panoramic view of primary liver cancer

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Cancer Biology & Medicine 2017年第4期14卷 335-340页

作者： Ruidong Xue Jing Li fan bai Xinwei Wang Junfang Ji Yinying Lu Comprehensive Liver Cancer Center Beijing 302 Hospital of PLA Beijing 100039 China Translational Cancer Research Center Peking University First Hospital Beijing 100034 China Biodynamic Optical Imaging Center (BIOPIC) School of Life Sciences Peking University Beijing 100871 China Department of Gastroenterology Peking University People's Hospital Beijing 100044 China Clinical Center of Immune-Mediated Digestive Diseases Peking University People's Hospital Beijing 100044 China Laboratory of Human Carcinogenesis Center for Cancer Research National Cancer Institute Bethesda MD 20892 USA Life Sciences Institute Zhejiang University Hangzhou 310058 China

Introduction Primary liver cancer, the second most common cause of cancer related death worldwide, presents ethnic, etiological, sex, and geographical diversity2 （Figure 1A）. At the histological level, liver cancer includes two major types： hepatocellular carcinoma （HCC, about 80%） and cholangiocarcinoma （CCA, about 15%）. Many etiological factors contribute to HCC development, such as hepatitis B virus （HBV）, hepatitis C virus （HCV）, aflatoxin B1 （AFB1）, alcohol, and metabolic diseases3. By contrast, the major risk factors for CCA are liver flukes （Opisthorchis viverrini and Clonorchis sinensis） and primary sclerosing cholangitis4,

关键词： A race to uncover a panoramic view of primary liver cancer

An improved CRISPRi system in Pichia pastoris

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Synthetic and Systems Biotechnology 2023年第3期8卷 479-485页

作者： Shujing Qiao fan bai Peng Cai Yongjin J.Zhou Lun Yao Division of Biotechnology Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian116023PR China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023PR China Dalian Key Laboratory of Energy Biotechnology Dalian Institute of Chemical PhysicsCAS457 Zhongshan RoadDalian116023PR China University of Chinese Academy of Sciences Beijing100049China

CRISPR interference(CRISPRi)has been developed and widely used for gene repression in various *** we report an improved CRISPRi system in Pichia pastoris by fusing dCas9 with endogenous transcriptional repressor *** CRISPRi system shows strong repression of eGFP,with the highest efficiency of 85%.Repression of native genes is demonstrated by targeting AOX1 ***1 is efficiently repressed and the mutant strains show much slower growth in methanol *** of gRNA expression and processing on CRISPRi efficiency is also *** is found that gRNA processing by HH/HDV ribozymes or Csy4 endoribonuclease generating clean gRNA is critical to achieve strong repression,and Csy4 cleavage shows higher repression ***,gRNA expression using native tRNA transcription and processing systems results in relatively weaker repression of *** expression of two gRNAs targeting promoters of eGFP and AOX1 in an array together with Cys4 recognition sites,both genes can be repressed ***4-mediated gRNA array processing is further applied to repress fatty acyl-CoA synthetase genes(FAA1 and FAA2).Both genes are efficiently repressed,demonstrating that Cys4 endoribonuclease has the ability to cleave gRNAs array and can be can be used for multiplexed gene repression in ***.

关键词： Pichia pastoris CRISPRi HH/HDV Csy4 gRNA array

Total Glucosides of Paeony Regulate Immune Imbalance Mediated by Dermal Mesenchymal Stem Cellsin Psoriasis Mice

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Chinese Journal of Integrative Medicine 2023年第6期29卷 517-525页

作者： LEI Ming-jun bai fan ZHANG Qing-yun YANG Qing-qing TIAN Zan Department of Dermatology Hebei Province Hospital of Chinese MedicineShijazhuang(050011)China

Objective To investigate the therapeutic effects of total glucosides of paeony(TGP)on psoriasis based on the immunomodulatory effect of dermal mesenchymal stem cells(DMSCs).Methods A total of 30 male BALB/c mice were divided into 6 groups(n=5 in each)by a random number table method,including control,psoriasis model(model,5%imiquimod cream 42 mg/d),low-,medium-and high-dose TGP(50,100,and 200 mg/kg,L,M-,and H-TGP,respectively),and positive control group(2.5 mg/kg acitretin).After 14 days of continuous administration,the skin’s histopathological changes,apoptosis,secretion of inflammatory cytokines,and proportion of regulatory T cells(Treg)and T helper cell 17(Th17)were evaluated using hematoxylin-eosin(HE)staining,TdT-mediated dUTP nick end labeling staining,enzyme-linked immunosorbent assay,and flow cytometry,*** were further isolated from the skin tissues of normal and psoriatic mice,and the cell morphology,phenotype,and cycle were ***,TGP was used to treat psoriatic DMSCs to analyze the effects on the DMSCs immune *** TGP alleviated skin pathological injury,reduced epidermis layer thickness,inhibited apoptosis,and regulated the secretion of inflammatory cytokines and the proportion of Treg and Th17 in the skin tissues of psoriatic mice(P0.05),however,more psoriatic DMSCs remained in G0/G1 phase compared with the normal DMSCs(P<0.01).TGP treatment of psoriatic DMSCs significantly increased cell viability,decreased apoptosis,relieved inflammatory response,and inhibited the expression of toll-like receptor 4 and P65(P<0.05 or P<0.01).Conclusion TGP may exert a good therapeutic effect on psoriasis by regulating the immune imbalance of DMSCs.

关键词： total glucosides of paeony psoriasis dermal mesenchymal stem cells inflammatory response immuneimbalance