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砷对核苷酸切除修复的抑制

科学通报 2012年第2期57卷 3208-3208页

作者：沈胜文王川 Michael Weinfeld 乐晓春 department of Laboratory medicine and Pathology Cross Cancer Institute University of Alberta

砷对DNA修复的抑制被认为是其产生共致突变作用/共致癌作用的一种途径.本文综述了有关砷化合物影响核苷酸切除修复（NER）的报道.对于核苷酸切除修复是如何被砷抑制的,目前已有好几种推测机制.

关键词：核苷酸切除修复砷化合物致突变作用 DNA修复致癌作用

Surface plasmon resonance and electrical properties of RF: magnetron sputtered carbon–nickel composite films at different annealing temperatures

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Rare Metals 2016年第11期35卷 863-869页

作者： Vali Dalouji S.Mohammad Elahi Sirvan Naderi department of Physics Malayer University Plasma Physics Research Center Science and Research BranchIslamic Azad University department of Physics Kermanshah BranchIslamic Azad University

In this work, the optical absorption spectra of carbon-nickel films annealed at different temperatures（300-1000 ℃） with a special emphasis on the surface plasmon resonance（SPR） were investigated. The films were grown on quartz substrates by radio-frequency（RF）magnetron co-sputtering at room temperature with a deposition time of 600 s. The optical absorption peaks due to the SPR of Ni particle are observed in the wavelength range of 300-330 nm. With annealing temperature increasing up to 500 ℃ due to the increase in Ni particle size, the intensity of the SPR peaks increases, but weakens with annealing temperature increasing over 500 ℃. The Ni nanoparticle size, the dielectric function of carbon matrix（ε_m） and the plasma frequency of the free electrons（ω_p） at500 ℃have the maximum values of 21.63 nm, 0.471 and5.26 9 10^（15）s^（-1）, respectively. The absorption peak shows a redshift trend up to 500 ℃and then turn to blueshift with annealing temperature increasing over 500 ℃ These observations are in a good agreement with the electrical measurements in temperature range of 15-520 K and the Maxwell-Garnett（M-G） effective medium theory（EMT）.

关键词： Surface plasmon resonance Carbon-nickelfilms Ni content Annealing temperatures Electricalresistivity

Analytical Solutions of Cracks Emanating from an Elliptic Hole in an Infinite Plate under Tension

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Chinese Journal of Mechanical Engineering 2014年第5期27卷 1057-1063页

作者： LIU Shuhong DUAN Shijie department of Engineering Mechanics Shijiazhuang Tiedao University The Key Laboratory for Health Monitoring and Control of Large Structures of Hebei Province department of Adult Education Shijiazhuang Tiedao University

It is a common phenomenon that the cracks originating from a hole can cause structural damage in ***,the fracture mechanics studies of hole edge crack problems are not *** problem of an elliptical hole with two collinear edge cracks of unequal length in an infinite plate under uniform tension at infinity is *** on the complex variable method,the analytical solutions of stress functions and stress intensity factors are *** stress distribution along the axes and the edge of the elliptical hole is given *** numerical results show that there is obvious stress concentration near the hole and cracks,and the stresses tend to applied loads at distances far from the defect,which conform to Saint-Venant’s ***,the stress functions are proved to be *** special conditions,the present configuration becomes the Griffith crack,two symmetrical cracks emanating from an elliptical hole,two cracks of unequal length emanating from a circular hole,a crack at the edge of a circular hole,or a crack emanating from an elliptical *** with available results,stress intensity factors for these special shapes of ellipses and cracks show good *** stress intensity factor for two cracks of unequal length at the edge of an elliptical hole increases with the crack length and the major-to-minor axis ratio of the elliptical *** stress distribution in an infinite plate containing an elliptic hole with unsymmetrical cracks is given for the first time.

关键词： hole crack stress distribution stress intensity factor

Coordinated RES and ESS Planning Framework Considering Financial Incentives Within Centralized Electricity Market

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 539-547页

作者： Kunpeng Tian Weiqing Sun Wei Liu He Song department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China department of Electrical Engineering University of Shanghai for Science and TechnologyShanghai 200093China

Coordinated investment and operations within renewable portfolio standards is one of the key technologies to meet the renewable energy target and realize the economic operations of the power *** paper proposes a unified framework of coordinated planning and financial *** investment in renewable energy and energy storage and joint optimization of energy and ancillary services are integrated into a unified *** factors are taken into consideration by the social planner in the centralized electricity market,such as the sitting and sizing of renewable energy and energy storage,charge and discharge efficiency of the energy storage,transmission network constraints,reserve capacity,and financial *** framework provides a tool for the social planner to determine the optimal planning scheme of renewable energy and energy *** conclusion derived is that the sum of market revenue and financial subsidies of renewable energy and energy storage is exactly equal to their investment cost which is obtained by the Karush-Kuhn-Tucker(KKT)condition of maximizing social welfare problems.A numerical result based on the modified IEEE-39 bus test system demonstrates the effectiveness of the unified *** impact of financial incentives,reserve capacity,and production costs on capital investment are studied.

关键词： Coordinated planning centralized electricity market financial incentives Karush-Kuhn-Tucker maximize social welfare

Lightweight Key Management Scheme Using Fuzzy Extractor for Wireless Mobile Sensor Network

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Computers, Materials & Continua 2022年第4期71卷 1695-1712页

作者： Eid Rehman Ibrahima Kalil Toure Kashif Sultan Muhammad Asif Muhammad Habib Najam Ul Hasan Oh-Young Song Aaqif Afzaal Abbasi department of Software Engineering Foundation UniversityIslamabad44000Pakistan Centre Informatique Universite Gamal Abdel Nasser deConakryGuinea department of Software Engineering Bahria University Islamabad CampusIslamabadPakistan GDC Ahmad Karak Higher Education DepartmentKhyber PakhtunkhwaPakistan department of Electrical and Computer Engineering Dhofar UniversitySalalahOman department of Software Sejong UniversitySeoul05006Korea

The mature design of wireless mobile sensor network makes it to be used in vast verities of applications including from home used to the security *** such types of applications based on wireless mobile sensor network are generally using real time data,most of them are interested in real time communication directly from cluster head of cluster instead of a base station in cluster *** would be possible if an external user allows to directly access real time data from the cluster head in cluster wireless mobile sensor network instead of accessing data from base *** this leads to a serious security breach and degrades the performance of any security protocol available in this *** existing schemes for authentication and cluster key management for external users,exchange a number of messages between cluster head and base station to allow external to access real time data from the base station instead of cluster *** increase communication cost and delay in such real time access *** handle this critical issue in cluster wireless mobile sensor network,we propose a lightweight authentication and key management scheme using a fuzzy *** this scheme,any external user can access data directly from the cluster head of any cluster without the involvement of the base *** proposed scheme only uses the one-way hash functions and bitwise XOR operations,apart from the fuzzy extractor method for the user biometric verification at the login *** presented scheme supports scalability for an increasing number of nodes using *** proposed scheme increases the life-time of the network by decreasing the key pool size.

关键词： Fuzzy extractor user authentication key management cluster session key wireless mobile sensor network

Gastroenterostoma after Billroth antrectomy as a premalignant condition

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World Journal of Gastroenterology 2012年第25期18卷 3201-3206页

作者： Robert Sitarz Ryszard Maciejewski Wojciech P Polkowski G Johan A Offerhaus department of Pathology University Medical CentreUtrecht3584 CX UtrechtThe Netherlands department of Human Anatomy Medical University of Lublin20-950 LublinPoland department of Surgical Oncology Medical University of Lublin20-081 LublinPoland department of Pathology Academic Medical Centre 1105 AZ Amsterdam The Netherlands

Gastric stump carcinoma （GSC） following remote gastric surgery is widely recognized as a separate entity within the group of various types of gastric cancer. Gastrecto- my is a well established risk factor for the development of GSC at a long time after the initial surgery. Both exo- as well as endogenous factors appear to be involved in the etiopathogenesis of GSC, such as achlorhydria, hypergastrinemia and biliary reflux, Epstein-Barr virus and Helicobacter pylori infection, atrophic gastritis, and also some polymorphisms in interleukin-l~ and maybe cyclo-oxygenase-2. This review summarizes the litera- ture of GSC, with special reference to reliable early di- agnostics. In particular, dysplasia can be considered as a dependable morphological marker. Therefore, close endoscopic surveillance with multiple biopsies of the gastroenterostomy is recommended. Screening start- ing at 15 years after the initial ulcer surgery can detect tumors at a curable stage. This approach can be ofspecial interest in Eastern European countries, where surgery for benign gastroduodenal ulcers has remained a practice for a much longer time than in Western Eu- rope, and therefore GSC is found with higher frequency.

关键词： Gastric stump cancer Gastrectomy Riskfactors Endoscopic surveillance

Isolation of marine benzo[a]pyrene-degrading Ochrobactrum sp. BAP5 and proteins characterization

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Journal of Environmental Sciences 2009年第10期21卷 1446-1451页

作者： WU Yirui HE Tengteng ZHONG Mingqi ZHANG Yueling LI Enmin HUANG Tongwang HU Zhong department of Biology Science College Shantou University Shantou 515063 China. department of Biochemistry and Molecular Biology Medical College Shantou University Shantou 515063 China

A bacterial strain BAP5 with a relatively high degradation ability of benzo[a]pyrene （BaP） was isolated from marine sediments of Xiamen Western Sea, China and identified as Ochrobactrum sp. according to 16S rRNA gene sequence as well as Biolog microbial identification system. Strain BAP5 could grow in mineral salt medium with 50 mg/L of BaP and degrade about 20% BaP after 30 d of incubation. Ochrobactrum sp. BAP5 was able to utilize other polycyclic aromatic hydrocarbons （PAHs）（such as phenanthrene, pyrene and fluoranthene） as the sole carbon source and energy source, suggesting its potential application in PAHs bioremediation. The profile of total soluble protein from Ochrobactrum sp. BAP5 was also investigated. Some over- and special-expressed proteins of strain BAP5 when incubated with the presence of BaP were detected by two-dimensional polyacrylamide gel electrophoresis, and found to be related with PAHs metabolism, DNA translation, and energy production based on peptide fingerprint analysis through matrix-assisted laser desorption/ionization-time of flight mass spectrometry.

关键词： benzo[a]pyrene biodegradation Ochrobactrum sp. BAP5 proteins

Magneto-rheological elastomer (MRE) based composite structures for micro-vibration control

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 345-356页

作者： YQ Ni ZG Ying ZH Chen department of Civil and Structural Engineering The Hong Kong Polytechnic University Hung Horn Kowloon Hong Kong China department of Mechanics Zhejiang University Hangzhou 310027 China

Magneto-rheological elastomers （MILEs） are used to construct composite structures for micro-vibration control of equipment under stochastic support-motion excitations. The dynamic behavior of MREs as a smart viscoelastic material is characterized by a complex modulus dependent on vibration frequency and controllable by external magnetic fields. Frequency-domain solution methods for stochastic micro-vibration response analysis of the MRE-based structural systems are developed to derive the system frequency-response function matrices and the expressions of the velocity response spectrum. With these equations, the root-mean-square （RMS） velocity responses in terms of the one-third octave frequency band spectrum can be calculated. Further, the optimization problem of the complex moduli of the MRE cores is defined by minimizing the velocity response spectra and the RMS velocity responses through altering the applied magnetic fields. Simulation results illustrate the influences of MRE parameters on the RMS velocity responses and the high response reduction capacities of the MRE-based structures. In addition, the developed frequency-domain analysis methods are applicable to sandwich beam structures with arbitrary cores characterized by complex shear moduli under stochastic excitations described by power spectral density functions, and are valid for a wide frequency range.

关键词： magneto-rheological elastomer (MRE) micro-vibration control equipment composite structure sandwich beam stochastic excitation

Digitalization of mine operations:Scenarios to benefit in real-time truck dispatching

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International Journal of Mining Science and Technology 2017年第2期27卷 229-236页

作者： Patarawan Chaowasakoo Heikki Seppala Heikki Koivo Quan Zhou department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland department of Mathematics and Systems Analysis School of SdenceAalto UniversityEspooFinland

One of the key factors in a profitable open-pit mine is the efficiency of the waste disposal system. Using GPS-technology, the truck-dispatching decisions can be made in real-time but the chosen strategy has a crucial role. Therefore, finding the optimal dispatching strategy for truck-shovel operations is extremely important. Dispatching strategies have been reported in the literature, but the comparison of these strategies is still missing. This paper illustrates the differences between the strategies by conducting a stochastic simulation study based on the data gathered from an actual mine. The findings underline the importance of the global vision in dispatching decisions.

关键词： Discrete event simulation GPS Truck dispatching Cycle time Fleet management