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Helicobacter pylori and 17β-estradiol induce human intrahepatic biliary epithelial cell abnormal proliferation and oxidative DNA damage

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Hepatobiliary & Pancreatic Diseases International 2017年第5期16卷 519-527页

作者： Fei ma Yong Yang Jian-Dong Wang zhi-Wei Quan Di zhou Department of Oncology Xinhua Hospital Shanghai Jiaotong University School of Medicine Department of General Surgery Shanghai Jiaotong University School of Medicine

BACKGROUND: Biliary cancers are more common in females, and previous studies have suggested that Helicobacter pylori (H. pylori) exists in the biliary system. However, the effects of H. pylori infection and estrogen on the biological behaviors of human biliary epithelium mucosa remain unknown. The present study aimed to clarify their effects on the proliferation, apoptosis, migration and oxidative DNA damage of a human intrahepatic biliary epithelial cell (HIBEC) line in vitro. METHODS: HIBECs were co -cultured with 17 beta-estradiol (at 10(-9) mol/L, 10(-7) mol/L, and 10(-5) mol/L) and H. pylori (at MOI=0.5:1, 1:1, and 2:1) and continuously passaged until the 15th generation (approximately 45 days). Then, the following assays were performed. HIBEC proliferation was measured using the CCK-8 assay, plate clone-formation assay and by determining Ki-67 expression with immunocytochemistry; cell apoptosis and migration were investigated using Annexin-V/PI and transwell assays, respectively; and reactive oxygen species (ROS) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) production were detected by flow cytometry and immunofluorescence staining combined with confocal laser scanning microscopy, respectively. The results were the basis for evaluating the level of oxidative stress and the related DNA damage in HIBECs. RESULTS: HIBECs maintained a normal morphology and vitality when treated with 17 beta-estradiol (at 10(-9) mol/L) and H. pylori (at MOI=0.5:1 and 1:1). 17 beta-estradiol at 10(-7) mol/L and 10(-5) mol/L and H. pylori at MOI=2:1, by contrast, caused cell death. Compared with controls, HIBECs treated with 17 beta-estradiol (10(-9) mol/L) and H. pylori (MOI=1:1) had a higher up-regulation of proliferation, Ki-67 expression, clone formation, migration activity and the expression of ROS and 8-OHdG and exhibited a down-regulation of apoptosis. The above effects were further increased when 17 beta-estradiol and H. pylori were combined (P<0.05). CONCLUSIONS: H. pylori and 17

关键词： H. pylori 17 beta-estradiol binary tract proliferation

Lattice Boltzmann simulation of solute transport in a single rough fracture

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Water Science and Engineering 2014年第3期7卷 277-287页

作者： zhi DOU zhi-fang zhou School of Earth Sciences and Engineering Hohai University

In this study, the lattice Boltzmann method （LBM） was used to simulate the solute transport in a single rough fracture. The self-affine rough fracture wall was generated with the successive random addition method. The ability of the developed LBM to simulate the solute transport was validated by Taylor dispersion. The effect of fluid velocity on the solute transport in a single rough fracture was investigated using the LBM. The breakthrough curves （BTCs） for continuous injection sources in rough fractures were analyzed and discussed with different Reynolds numbers （Re）. The results show that the rough frac~＇e wall leads to a large fluid velocity gradient across the aperture. Consequently, there is a broad distribution of the immobile region along the rough fracture wall. This distribution of the immobile region is very sensitive to the Re and fracture geometry, and the immobile region is enlarged with the increase of Re and roughness. The concentration of the solute front in the mobile region increases with the Re. Furthermore, the Re and roughness have significant effects on BTCs, and the slow solute molecule exchange between the mobile and immobile regions results in a long breakthrough tail for the rough fracture. This study also demonstrates that the developed LBM can be effective in studying the solute transport in a rough fracture.

关键词： solute transport single rough fracture Lattice Boltzmann method, self-affinity breakthrough curve

Rehearsal:learning from prediction to decision

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Frontiers of Computer Science 2022年第4期16卷 1-3页

作者： zhi-Hua zhou National Key Laboratory for Novel Software Technology Nanjing UniversityNanjing210023China

machine learning[1]studies focus mostly on prediction,where a model is built from a set of observational data formaking correct predictions on unseen *** has beenaddressed very well by modem techniques such as deeplea... 详细信息

关键词： such has see

A brief introduction to weakly supervised learning

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National Science Review 2018年第1期5卷 44-53页

作者： zhi-Hua zhou National Key Laboratory for Novel Software Technology Nanjing University

Supervised learning techniques construct predictive models by learning from a large number of training examples, where each training example has a label indicating its ground-truth output. Though current techniques have achieved great success; it is noteworthy that in many tasks it is difficult to get strong supervision information like fully ground-truth labels due to the high cost of the data-labeling process. Thus,it is desirable for machine-learning techniques to work with weak supervision. This article reviews some research progress of weakly supervised learning, focusing on three typical types of weak supervision:incomplete supervision, where only a subset of training data is given with labels; inexact supervision, where the training data are given with only coarse-grained labels; and inaccurate supervision, where the given labels are not always ground-truth.

关键词： machine learning weakly supervised learning supervised learning

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阿片类药物诱导瘙痒的机制研究进展

中国药理学通报 2025年第1期41卷 29-34页

作者：马芳周培岚苏瑞斌军事医学研究院国家安全特需药品全国重点实验室北京100850 南京中医药大学药学院江苏南京210046

瘙痒是临床使用阿片类药物镇痛的患者普遍存在的严重不良反应之一。大量研究已经阐明阿片类药物的镇痛机制,但阿片类药物诱导瘙痒的机制尚不明确,瘙痒与镇痛之间的关系也模糊不清。目前的研究发现,阿片类药物作用于μ、κ及δ阿片受体后... 详细信息

瘙痒是临床使用阿片类药物镇痛的患者普遍存在的严重不良反应之一。大量研究已经阐明阿片类药物的镇痛机制,但阿片类药物诱导瘙痒的机制尚不明确,瘙痒与镇痛之间的关系也模糊不清。目前的研究发现,阿片类药物作用于μ、κ及δ阿片受体后,直接或间接影响瘙痒关键受体——胃泌素释放肽受体的功能,进而影响瘙痒信息传递。神经介素B、神经肽Y、B型利钠肽等神经肽,以及其他受体如瞬时受体电位香草素1受体、N-甲基-D-天冬氨酸受体、5-羟色胺受体等,在吗啡诱导的瘙痒中也具有重要作用。此外,阿片类药物所致瘙痒的预防和治疗也是围手术期吗啡镇痛的难点和热点之一。因此,明确瘙痒的具体发生机制,对寻找新的研究思路及预防和治疗阿片类药物诱导的瘙痒具有重要意义。

关键词：阿片类诱导的瘙痒瘙痒与镇痛瘙痒机制阿片受体胃泌素释放肽受体瘙痒治疗

Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting

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Journal of Energy Chemistry 2025年第1期100卷 26-38页

作者： Xiaodong Yang Haochen Shen Xiaoming Xiao zhichao Li Qi zhou Wei Yang Bin Jiang Yongli Sun Luhong Zhang Zhenhua Yan School of Chemical Engineering and Technology Tianjin University Key Laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University

This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides （M/SLDH） through spontaneous redox and sulfurization *** developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction （OER） and hydrogen evolution reaction （HER） performance,achieving low overpotentials of 212 and 35 mV at 10 ma cm-2in 1 M KOH,*** both anode and cathode in water splitting,they required only 1.47 V to reach 10 ma cm-2and exhibited high structural robustness,maintaining stability at 1000 ma cm-2for 300 ***-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water ***,ultraviolet photoelectron spectroscopy （UPS） and density functional theory （DFT） analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER *** study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.

关键词： Ultraviolet photoelectron spectroscopy

Thermal–moisture dynamics and thermal stability of active layer in response to wet/dry conditions in the central region of the Qinghai–Tibet Plateau,China

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Research in Cold and Arid Regions 2023年第1期15卷 27-38页

作者： MingLi Zhang zhiXiong zhou zhi Wen FengXi zhou Zhao ma BingBing Lei College of Civil Engineering Lanzhou University of TechnologyLanzhouGansu 730050China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Geological Hazards Prevention Institute Gansu Academy of SciencesLanzhouGansu 730000China College of Civil Engineering Lanzhou Jiaotong UniversityLanzhouGansu 730070China

The amount of rainfall varies unevenly in different regions of the Qinghai-Tibet Plateau, with some regions becoming wetter and others drier. Precipitation has an important impact on the process of surface energy balance and the energy-water transfer within soils. To clarify the thermal-moisture dynamics and thermal stability of the active layer in permafrost regions under wet/dry conditions, the verified water-vapour-heat coupling model was used. Changes in the surface energy balance, energy-water transfer within the soil, and thickness of the active layer were quantitatively analyzed. The results demonstrate that rainfall changes significantly affect the Bowen ratio, which in turn affects surface energy exchange. Under wet/dry conditions, there is a positive correlation between rainfall and liquid water flux under the hydraulic gradient;water vapour migration is the main form under the temperature gradient, which indicates that the influence of water vapour migration on thermalmoisture dynamics of the active layer cannot be neglected. Concurrently, regardless of wet or dry conditions,disturbance of the heat transport by conduction caused by rainfall is stronger than that of convection by liquid water. In addition, when rainfall decreases by 1.5 times(212 mm) and increases by 1.5 times(477 mm), the thickness of the active layer increases by 0.12 m and decreases by 0.21 m, respectively. The results show that dry conditions are not conducive to the preservation of frozen soil;however, wet conditions are conducive to the preservation of frozen soil, although there is a threshold value. When this threshold value is exceeded, rainfall is unfavourable for the development of frozen soil.

关键词： Active layer Wet/dry conditions Qinghai-Tibet Plateau(QTP) Thermal-moisture dynamics Permafrost thermal stability Numerical modelling

Modeling,Characterization,and Application of Soft Bellows-Type Pneumatic Actuators for Bionic Locomotion

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Acta Mechanica Solida Sinica 2023年第1期36卷 1-12页

作者： Huichen ma Junjie zhou School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Advanced Technology Beijing Institute of TechnologyJinan 250101China

Soft bellows-type pneumatic actuators(SBPAs),which consist of two cavities with small chambers embedded in elastomeric structures,are an essential embranchment in the field of soft ***,more analytical modeling and analysis of SBPAs need to be *** this article,we first present the structure design,fabrication method,and material property test of the ***,based on the plate bending theory,an analytical model and the corresponding design approach for SBPAs are established,which consider both geometric complexity and material *** verification results indicate that the predicted analytical results coincide well with the physical experimental measurement and simulation *** decision coefficient is R^(2)=*** impacts of geometric dimensions and silicone material characteristics on the bending deformation of SBPAs are also *** further demonstrate the bionic utility of *** an approach can be used as a tool for the design optimization of bellows-type actuators and save the designer lots of finite element analysis with its low computational *** work provides a detailed investigation of the performance of SBPAs,which can be a basic module for various types of soft robots such as soft snake robots,crawling robots,and robotic arms in the future.

关键词： Plate bendingtheory Soft actuator Modeling Bionic application

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Deep forest

National Science Review 2019年第1期6卷 74-86页

作者： zhi-Hua zhou Ji Feng National Key Laboratory for Novel Software Technology Nanjing University

Current deep-learning models are mostly built upon neural networks, i.e. multiple layers of parameterized differentiable non-linear modules that can be trained by backpropagation. In this paper, we explore the possibility of building deep models based on non-differentiable modules such as decision trees. After a discussion about the mystery behind deep neural networks, particularly by contrasting them with shallow neural networks and traditional machine-learning techniques such as decision trees and boosting machines,we conjecture that the success of deep neural networks owes much to three characteristics, ***-by-layer processing, in-model feature transformation and sufficient model complexity. On one hand,our conjecture may offer inspiration for theoretical understanding of deep learning; on the other hand, to verify the conjecture, we propose an approach that generates deep forest holding these characteristics. This is a decision-tree ensemble approach, with fewer hyper-parameters than deep neural networks, and its model complexity can be automatically determined in a data-dependent way. Experiments show that its performance is quite robust to hyper-parameter settings, such that in most cases, even across different data from different domains, it is able to achieve excellent performance by using the same default setting. This study opens the door to deep learning based on non-differentiable modules without gradient-based adjustment, and exhibits the possibility of constructing deep models without backpropagation.

关键词： deep forest deep learning machine learning ensemble methods decision trees