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Attack Vulnerability of Network with Duplication-Divergence Mechanism

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Communications in Theoretical Physics 2007年第4X期48卷 754-758页

作者： WANG Li YAN Jia-Ren LIU zi-Ran zhang jian-Guo Department of Physics Hunan Normal University Changsha 410081 China

We study the attack vulnerability of network with duplication-divergence mechanism. Numerical results have shown that the duplication-divergence network with larger retention probability a is more robust against target attack relatively. Furthermore, duplication-divergence network is broken down more quickly than its counterpart BA network under target attack. Such result is consistent with the fact of WWW and Internet networks under target attack. So duplication-divergence model is a more realistic one for us to investigate the characteristics of the world wide web in future. We also observe that the exponent γ of degree distribution and average degree are important parameters of networks, reflecting the performance of networks under target attack. Our results are helpful to the research on the security of network.

关键词： complex network systems attack vulnerability statistical dynamics

Risk factors for lower limb swelling after primary total knee arthroplasty

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Chinese Medical Journal 2011年第23期124卷 3896-3899页

作者： GAO Fu-qiang LI zi-jian zhang Ke David Huang LIU Zhong-jun Department of Orthopaedics Peking University Third Hospital Beijing 100191 China

Total knee arthroplasty （TKA） is a successful surgical technique for patients with advanced knee osteoarthritis; however, some peri-operative complications can not be predicted or avoided completely. This study aimed to investigate the factors affecting limb swelling after primary total knee arthroplasty, to guide and improve patient rehabilitation. Methods Using a hospital database, we retroactively analyzed the mean changes in limb circumferences of 286 consecutive patients who underwent primary unilateral total knee arthroplasty between October 2007 and August 2009. The lower limb circumference change was calculated and analyzed statistically. The influence of age, gender, body mass index, the presence of deep vein thrombosis, methods of anti-coagulation, operation time, hidden blood loss, and type of prosthesis on post-operative lower limb swelling was studied. Results Swelling was most pronounced from the third to the fifth post-operative day and usually occurred in both lower limbs. Swelling was significantly more pronounced in the operated limb than in the non-operated limb. The swelling above the knee was also significantly greater than that below the knee. The change in limb circumference at 10 cm above the knee was significantly different between the patients with body mass index 〈25 kg/m2 and those with body mass index 〉25 kg/m2. However, the change in limb circumference at 10 cm below the knee was not significantly different between the two groups. There was no statistically significant difference in limb swelling between different age groups （P 〉0.05）. Similarly, gender, methods of anti-coagulation, the presence of deep vein thrombosis, the type of prosthesis, and operation time did not significantly affect post-operative limb swelling. Multivariate linear regression showed that the factors affecting post-operative limb swelling were body mass index and hidden blood loss. Conclusions Lower limb swelling after total knee arthroplasty is related to early

关键词： total knee arthroplasty swelling risk factors

Modulation of d-orbital to realize enriched electronic cobalt sites in cobalt sulfide for enhanced hydrogen evolution in electrocatalytic water/seawater splitting

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Rare Metals 2024年第2期43卷 511-521页

作者： jian-Peng Sun Yu Zheng zi-Sheng zhang Xiang-Chao Meng zi-Zhen Li Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao266100China Shanxi Institute of Energy Taiyuan030600China Department of Chemical and Biological Engineering Faculty of EngineeringUniversity of OttawaOttawaONK1N6 N5Canada

Herein,a novel single-atomic Pt doping and interface-rich CoS/Co(OH)_(2)(Pt-CoS/Co(OH)_(2)/C)electrocatalyst has been successfully *** from precise regulation of d-orbital electronic structure modulation on Co site,Pt-CoS/Co(OH)_(2)/C exhibited remarkable HER activity and high stability for hydrogen evolution in splitting both water(73 mV@10 mA·cm^(−2)) and seawater(87 mV@10 mA·cm^(−2)).Notably,atomic Pt doping was introduced into CoS/Co(OH)_(2),which could produce local unbalanced Coulombic force and significantly increased the number of S vacancies,and then expose abundant Co ***,Co(OH)_(2) in Pt-CoS/Co(OH)_(2)/C could act as the adsorption sites for H_(2)O in hydrogen evolution reaction *** functional theory results also proved that atomic Pt doping,S vacancies and Co(OH)_(2) coupling could result in the formation of enriched electronic Co sites and optimize d_(z2) orbital electronic structure,and then realize the depth upward shift of d-band center and enhance the adsorption of H*on Co sites.

关键词： Electrocatalysts Hydrogen evolution reaction Pt-CoS/Co(OH)_(2) d-band center Electronic structure Water/seawater electrolysis

Photodynamic therapy regulates fate of cancer stem cells through reactive oxygen species

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World Journal of Stem Cells 2020年第7期12卷 562-584页

作者： zi-jian zhang Kun-Peng Wang Jing-Gang Mo Li Xiong Yu Wen Department of General Surgery Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Department of General Surgery Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina

Photodynamic therapy(PDT)is an effective and promising cancer *** directly generates reactive oxygen species(ROS)through photochemical *** oxygen-dependent exogenous ROS has anti-cancer stem cell(CSC)*** addition,PDT may also increase ROS production by altering metabolism,endoplasmic reticulum stress,or potential of mitochondrial *** is known that the half-life of ROS in PDT is short,with high reactivity and limited diffusion ***,the main targeting position of PDT is often the subcellular localization of photosensitizers,which is helpful for us to explain how PDT affects CSC characteristics,including differentiation,selfrenewal,apoptosis,autophagy,and *** speaking,excess ROS will damage the redox system and cause oxidative damage to molecules such as DNA,change mitochondrial permeability,activate unfolded protein response,autophagy,and CSC resting ***,understanding the molecular mechanism by which ROS affect CSCs is beneficial to improve the efficiency of PDT and prevent tumor recurrence and *** this article,we review the effects of two types of photochemical reactions on PDT,the metabolic processes,and the biological effects of ROS in different subcellular locations on CSCs.

关键词： Cancer stem cells Photodynamic therapy Reactive oxygen species Photosensitizer Mitochondrial Endoplasmic reticulum

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： Wen-Jun Cai jian-Guo jiang zi-Dong zhang zi-Xuan Liu Lu-Jiezhang Zhen-Kun Long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)

Shielding of the geomagnetic field reduces hydrogen peroxide production in human neuroblastoma cell and inhibits the activity of CuZn superoxide dismutase

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Protein & Cell 2017年第7期8卷 527-537页

作者： Hai-tao zhang zi-jian zhang Wei-chuan Mo Ping-dong Hu Hai-min Ding Ying Liu Qian Hua Rong-qiao He State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Beijing Chinese Traditional Medicine Beijing University of Chinese Medicine Beijing 100029 China CAS KeY Laboratory of Mental Health Institute of Psychology Beijing 100101 China

Accumulative evidence has shown the adverse effects of a geomagnetic field shielded condition, so called a hypomagnetic field （HMF）, on the metabolic processes and oxidative stress in animals and cells. However, the underlying mechanism remains unclear. In this study, we evaluate the role of HMF on the regulation of cellular reactive oxygen species （ROS） in human neuroblastoma SH-SY5Y cells. We found that HMF exposure led to ROS decrease, and that restoring the decrease by additional H2O2 rescued the HMF-enhanced cell proliferation. The measurements on ROS related indexes, including total anti-oxidant capacity, H2O2 and superoxide anion levels, and superoxide dismutase （SOD） activity and expres- sion, indicated that the HMF reduced H2O2 production and inhibited the activity of CuZn-SOD. Moreover, the HMF accelerated the denaturation of CuZn-SOD as well as enhanced aggregation of CuZn-SOD protein, in vitro. Our findings indicate that CuZn-SOD is able to response to the HMF stress and suggest it a mediator of the HMF effect.

关键词： hypomagnetic field reactive oxygenspecies hydrogen peroxide superoxide dismutase,oxidative stress

Sequence structure controllable polymerization-induced self-assembly

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Science China Chemistry 2024年第1期67卷 390-397页

作者： zi-Xuan Chang Ren-Man Zhu Chun-Yan Hong Wen-jian zhang Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Laboratory of Environment-Friendly Polymeric Materials of Anhui Province Anhui UniversityHefei 230601China

Polymerization-induced self-assembly(PISA)combines synthesis and self-assembly of artificial polymers in one-pot,which brings us one step closer to emulating ***,the reported PISA formulations primarily focus on developing nano-objects with new chemical compositions and rarely on structural regulation of polymers with specific ***,sequence structure controllable polymerization-induced self-assembly(SCPISA)is reported by using 7-(2-methacryloyloxyethoxy)-4-methylcoumarin(CMA)as a *** the copolymerization of 2-hydroxyethyl methacrylate(HEMA)and CMA,controlled incorporation of CMA units into the polymer chains can be realized by programmable light/heat ***-based P(HEMA-co-CMA)copolymers with the same composition but different sequence structures generate a range of ***,the morphologies of the resultant nano-objects can also be controlled by regulating the feed molar ratio of CMA and HEMA,which is similar to the conventional PISA,but the synthesis procedure is obviously simplified in *** versatility of the methodology is further demonstrated by the fabrication of different functional nano-objects with sequence structure-dependent morphologies in SCPISA systems with different functional monomers.

关键词： polymerization-induced self-assembly sequence-controlled polymers PET-RAFT polymerization

Novel perspective in pancreatic cancer therapy:Targeting ferroptosis pathway

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World Journal of Gastrointestinal Oncology 2021年第11期13卷 1668-1679页

作者： Yang Yang zi-jian zhang Yu Wen Li Xiong Yun-Peng Huang Yong-Xiang Wang Kai Liu Department of General Surgery The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

Pancreatic cancer is a highly lethal malignancy with low resection and survival rates and is not sensitive to radiotherapy and *** is a novel form of nonapoptotic regulated cell death characterized by the accumulation of lipid peroxides and reactive oxygen species involved in iron *** has a significant role in the occurrence and development of various *** studies have shown that regulating ferroptosis-induced cell death inhibited tumor growth in pancreatic cancer and was synergistic with other antitumor drugs to improve treatment ***,we discuss the mechanism,inducers,and developments of ferroptosis in pancreatic cancer to provide new strategies for the treatment of the malignancy.

关键词： Pancreatic cancer Ferroptosis Reactive oxygen species Iron metabolism Lipid peroxides

Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities

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Petroleum Science 2024年第3期21卷 1992-2004页

作者： Ji-Yun zhang Chi Peng jian-Hong Fu Quan Cao Yu Su jian-Yun Pang zi-Qiang Yu Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Engineering Technology Research Institute of CNPC Southwest Oil and Gas Field Company Chengdu610017SichuanChina

To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional ***,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the *** address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse *** model investigates the stress distribution of each thread tooth subjected to various tensile forces and external ***,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental *** findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread *** end thread teeth are valuable spots for *** is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth *** external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield *** tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element *** tensile strength of the joint is 3091.9 k ***,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test resul

关键词： Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength