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Journal of Coal Science & Engineering(China) 2012年第4期18卷 379-384页

作者： BI Yuan-zhi ZHANG da-lin HU jin-hua School of Environment and Civil Engineering Jiangnan UniversityWuxi 214122China Shanghai datun Energy Resources Co. Ltd.Xuzhou 221600China

The an thors developed a new composite cement base material by mixing the high tenacity polypropylene （coarse） fiber in plain cement base for the cement-layer-spray technology. By studying the key parameters of the fiber dosage, the spray layer thickness, and the fiber reinforced concrete injection time, etc. It is found that the ideal volume ratio of polypropylene （crude） fiber is 0.8% （V/V）, and the secondary lining fiber concrete spraying should start when the shrinkage rate is lower than 0.5 mm/d, and the optimal thickness of shotcrete is 120 mm. The supporting effects and the economic benefits were studied using a real project practice, and the result obtained can be a good reference for practical applications of this new supporting material in the future.

关键词： deep mine roadway modified polypropylene (crude) fiber supporting structure mine stress

Hepatic perfusion disorders: Etiopathogenesis and related diseases

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World Journal of Gastroenterology 2006年第20期12卷 3265-3270页

作者： jin-lin Tian jin-Shan Zhang Department of Radiology Chinese PLA General Hospital Beijing 100853 China

In this article, we have reviewed the hepatic perfusion disorder （HPD）, etiopathogenesis of HPD and corresponding diseases. Review of the literature was based on computer searches （PubMed, Index Medicus） and personal experiences. We considered HPD reflects perfusion differences due to redistribution of arterial blood flow among segments, subsegments and lobes of the liver. The plain CT scan findings of HPD manifests as triangular or wedge-shaped areas of low attenuation. On contrast-enhanced CT scan, HPD manifests multiple （or single） transient wedge-shaped, rotundloid or irregular appearance, homogeneous hyperattenuation （in less cases, hypoattenuation） during the hepatic arterial phase （HAP） and isoattenuated or slightly hyperattenuated areas during the portal arterial phase. Dynamic enhanced magnetic resonance （MR） features are similar to enhanced CT scan. Angiographic findings include non-opacification of portal vein on portograms or wedge-shaped segmental staining in arterial and parenchymal phases on hepatic angiograms. The causes of HPD are arterioportal shunts （APS）, intrahepatic vascular compressions and portal vein occlusion, steal phenomenon by hypervascular tumors, vascular variations and any other unknown reasons. It is very important for radiologists to be familiar with the various appearances of HPD to avoid false-positive diagnosis of pseudolesions and not to overestimate the extent of the disease.

关键词： Etiopathogenesis Hepatic perfusion disorders Diseases

Effects of domain unfolding and catch-like dissociation on the collective behavior of integrin-fibronectin bond clusters

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Acta Mechanica Sinica 2021年第2期37卷 229-243页

作者： Ji lin Yanzhong Wang jin Qian Department of Engineering Mechanics Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang UniversityHangzhou 310027China

To gain more understanding of cell-matrix adhesion,we consider an idealized theoretical model of a cluster of integrin-fibronectin bonds at the cell-matrix interface subjected to a dynamic *** distributions of bond traction and interfacial deformation are assumed to obey classical elastic equations,whereas the dissociation/association of individual bonds as well as unfolding/refolding of fibronectin domains are described by stochastic *** stochastic-elasticity coupling,we perform Monte Carlo simulations to investigate how the collective behavior and adhesion performance of the integrin-fibronectin-mediated interface are influenced by two characteristics newly incorporated in the modeling,i.e.,catchlike dissociation between integrin and fibronectin,and unfolding of repeated domains in *** probable unfolding of fibronectin domains is found to have profound effects on the resultant adhesion energy of the integrin-fibronectin-mediated interface,and governs the failure model transiting between uniform decay and catastrophic crack-like rupture.

关键词： Integrin-fibronectin complex Cell-matrix adhesion Domain unfolding Catch bond Rate dependence Modulus effect

On the Martensitic Transformation Temperatures and Mechanical Properties of NiTi Alloy Manufactured by Selective Laser Melting: Effect of Remelting

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Acta Metallurgica Sinica(English Letters) 2021年第9期34卷 1223-1233页

作者： Jian-Bin Zhan Yan-jin Lu jin-Xin lin College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

In this study, the infl uence of laser remelting on the relative density, martensitic transformation temperatures(MTTs), and mechanical properties of a NiTi alloy fabricated by selective laser melting(SLM) at a laser power between 15 and 75 W were investigated. A relative alloy density of approximately 99% was achieved in the power range of 45–60 W corresponding to the forming energy density range of 65.45–87.27 J/mm3. The MTTs increased with the increase in the energy density;thus, the initial contents of the B2 and B19′ phases of the SLM-produced NiTi alloy can be tailored by the utilized technique. However, the number of defects such as metallurgical pores and microcracks considerably increased at higher energy densities(> 87.27 J/mm3). Interestingly, the concentration of these defects was reduced by remelting in the energy density range of 21.82–65.45 J/mm3, while the alloy relative density increased to 99.7% ± 0.1% at a remelting energy density of 65.45 J/mm3. The results of tensile testing revealed that when the remelting energy was 75% or 100% of the forming energy input, the ultimate tensile strength and elongation of the alloy significantly increased. Therefore, the remelting strategy represents a promising route for manufacturing NiTi alloys with desired MTT ranges and mechanical properties.

关键词： Selective laser melting NiTi alloy Laser remelting Martensitic transformation temperature

Resolution Enhancement in Ultrasonic TOFD Imaging by Combining Sparse Deconvolution and Synthetic Aperture Focusing Technique(Sparse-SAFT)

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 141-149页

作者： Xu Sun Li lin Shijie jin School of Materials Science and Engineering Dalian University of TechnologyDalianChina

The shallow subsurface defects are difficult to be identified and quantified by ultrasonic time-of-flight diffraction(TOFD)due to the low resolution induced by pulse width and beam *** this paper,Sparse-SAFT is proposed to improve the time resolution and lateral resolution in TOFD imaging by combining sparse deconvolution and synthetic aperture focusing technique(SAFT).The mathematical model in the frequency domain is established based on the l1 and l2 norm constraints,and the optimization problem is solved for enhancing time *** this basis,SAFT is employed to improve lateral resolution by delay-and-sum *** simulated and experimental results indicate that the lateral wave and tip-diffracted waves can be decoupled with *** shallow subsurface defects with a height of 3.0 mm at the depth of 3.0 mm were detected quantitatively,and the relative measurement errors of flaw heights and depths were no more than 10.3%.Compared to conventional SAFT,the time resolution and lateral resolution are enhanced by 72.5 and 56%with Sparse-SAFT,***,the proposed method is also suitable for improving resolution to detect the defects beyond dead zone.

关键词： Time resolution Lateral resolution Time-of-flight diffraction(TOFD) Sparse deconvolution Synthetic aperture focusing technique(SAFT) Sparse-SAFT

PSA time to nadir as a prognostic factor of first-line docetaxel treatment in castration-resistant prostate cancer： evidence from patients in Northwestern China

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Asian Journal of Andrology 2018年第2期20卷 173-177页

作者： Kai-Jie Wu Xin-Qi Pei Ge Tian da-Peng Wu jin-Hai Fan Yu-Mei Jiang da-lin He Department of Urology The First Affiliated Hospital of Xi'an Jiaotong University Xi'an 710061 China

Docetaxel-based chemotherapy remains the first-line treatment for patients with metastatic castration-resistant prostate cancer （mCRPC） in China; however, the prognostic factors associated with effects in these patients are still controversial. In this study, we retrospectively reviewed the data from 71 eligible Chinese patients who received docetaxel chemotherapy from 2009 to 2016 in our hospital and experienced a reduction of prostate-specific antigen （PSA） level 〉50% during the treatment and investigated the potential role of time to nadir （TTN） of PSA. TTN was defined as the time from start of chemotherapy to the nadir of PSA level during the treatment. Multivariable Cox regression models and Kaplan-Meier analysis were used to predict overall survival （OS）. In these patients, the median of TTN was 17 weeks. Patients with TTN ≥17 weeks had a longer response time to chemotherapy compared to TTN 〈17 weeks （42.83 vs 21.50 weeks, P 〈 0.001）. The time to PSA progression in patients with TTN ：〉17 weeks was 11.44 weeks compared to 5.63 weeks when TTN was 〈17 weeks. We found several factors to be associated with OS, including TTN （hazard ratio [HR]. 3.937, 95% confidence interval [CI]： 1.502-10.309, P = 0.005）, PSA level at the diagnosis of cancer （HR： 4,337, 95% CI： 1.616-11.645, P= 0.004）, duration of initial androgen deprivation therapy （HR： 2.982, 95% CI： 1.104-8.045, P= 0.031）, neutrophil-to-lymphocyte ratio （HR： 3.963, 95% CI： 1.380-11.384, P = 0.011）, and total PSA response （Class 1 [〈0 response] compared to Class 2 [0-50% response], HR： 3.978, 95% CI： 1.278-12.387, P = 0.017）. In conclusion, TTN of PSA remains an important prognostic marker in predicting therapeutic outcome in Chinese population who receive chemotherapy for mCRPC and have 〉50% PSA remission.

关键词： castration-resistant prostate cancer chemotherapy docetaxel prostate-specific antigen survival time to nadir

A learning-based synthesis approach to decentralized supervisory control of discrete event systems with unknown plants

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Control Theory and Technology 2014年第3期12卷 218-233页

作者： jin daI Hai lin Department of Electrical Engineering University of Notre DameNotre Dame IN 46556 U.S.A.

In this paper, we consider the problem of automatic synthesis of decentralized supervisor for uncertain discrete event systems. In particular, we study the case when the uncontrolled plant is unknown a priori. To deal with the unknown plants, we first characterize the conormality of prefix-closed regular languages and propose formulas for computing the supremal conormal sublanguages; then sufficient conditions for the existence of decentralized supervisors are given in terms of language controllability and conormality and a learning-based algorithm to synthesize the supervisor automatically is proposed. Moreover, the paper also studies the on-line decentralized supervisory control of concurrent discrete event systems that are composed of multiple interacting unknown modules. We use the concept of modular controllability to characterize the necessary and sufficient conditions for the existence of the local supervisors, which consist of a set of local supervisor modules, one for each plant module and which determines its control actions based on the locally observed behaviors, and an on-line learning-based local synthesis algorithm is also presented. The correctness and convergence of the proposed algorithms are proved, and their implementation are illustrated through examples.

关键词： Discrete-event systems Supervisor synthesis Regular language learning Controllability Decentralized control

Increased Maleness at Flowering Stage and Femaleness at Fruiting Stage with Size in an Andromonoecious Perennial, Veratrum nigrum

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Journal of Integrative Plant Biology 2008年第8期50卷 1024-1030页

作者： Wan-jin Liao da-Yong Zhang Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering & Institute of Ecology Beijing Normal University Beijing 100875 China

Theory predicts that cosexual plants should adjust their resource investment in male and female functions according to their size if female and male fitness are differentially affected by size. However, few empirical studies have been carried out at both the flowering and fruiting stages to adequately address size-dependent sex allocation in cosexual plants. In this paper, we investigated resource investment between female and male reproduction, and their size-dependence in a perennial andromonoecious herb, Veratrum nigrum L. We sampled 192 flowering plants, estimated their standardized phenotypic gender, and assessed the resource investment in male and female functions in terms of absolute dry biomass. At the flowering stage, male investment increased with plant size more rapidly than female investment, and the standardized phenotypic femaleness （ranging from 0.267 to 0.776） was negatively correlated with plant size. By contrast, female biased allocation was found at the fruiting stage, although both flower biomass and fruit biomass were positively correlated with plant size. We propose that increased maleness with plant size at the flowering stage may represent an adaptive strategy for andromonoecious plants, because male flowers promote both male and female fertility by increasing pollinator attraction without aggravating pollen discounting.

关键词： andromonoecy phenotypic gender size-dependent sex allocation Veratrum nigrum

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He Chang Yang YuYue jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

Non-catalytic roles for TET1 protein negatively regulating neuronal differentiation through srGAP3 in neuroblastoma cells

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Protein & Cell 2016年第5期7卷 351-361页

作者： Jie Gao Yue Ma Hua-lin Fu Qian Luo ZhenWang Yu-Huan Xiao Hao Yang da-Xiang Cui Wei-lin jin School of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China institute of Nano Biomedicine and Engineering Department of Instrument Science and Engineering School of Electronic Information and Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China National Center for Translational Medicine Shanghai Jiao Tong University Shanghai 200240 China Department of Experimental Surgery Tangdu Hospital Fourth Military Medical University Xi'an 710038 China Clinical Stem Cell Research Center Renji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200127 China

The methylcytosine dioxygenases TET proteins （TET1, TET2, and TET3） play important regulatory roles in neural function. In this study, we investigated the role of TET proteins in neuronal differentiation using Neuro2a cells as a model. We observed that knockdown of TET1, TET2 or TET3 promoted neuronal differentiation of Neuro2a cells, and their overexpression inhibited VPA （valproic acid）-induced neuronal differentiation, suggesting all three TET proteins negatively regulate neu- ronal differentiation of Neuro2a cells. Interestingly, the inducing activity of TET protein is independent of its enzymatic activity. Our previous studies have demon- strated that srGAP3 can negatively regulate neuronal differentiation of Neuro2a cells. Furthermore, we revealed that TET1 could positively regulate srGAP3 expression independent of its catalytic activity, and srGAP3 is required for TET-mediated neuronal differentiation of Neuro2a cells. The results presented here may facilitate better understanding of the role of TET proteins in neuronal differentiation, and provide a possible therapy target for neuroblastoma.

关键词： methylcytosine dioxygenase TET1,srGAP3 neuronal differentiation neuroblastoma cells