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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 275-284页

作者： L.M.Liu Y.X.Lai c.L.Wu Z.Zhang J.H.chen center for High-Resolution Electron Microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China

This study investigates the microstructure and local corrosion behavior of an Al-Mg-Si-cu alloy,which has been subjected to cold-rolling with different deformation strain ratios(DSRs)and followed by artificial *** corrosion tests show that peak-aged samples with a small DSR(5-10%)are sensitive to inter-granular corrosion(IGc)along both the normal and rolling *** the DSR increases to medium strength(20-40%),IGc sensitivity decreases along both directions and corrosion propagates *** the DSR is 60-80%,IGc sensitivity along the normal direction continues to decrease,but increases along the rolling direction,indicating pronounced corrosion *** characterization reveals the decreased IGc sensitivity is mainly attributed to a reduction in element segregation at high-angle grain boundaries and the kinked and discontinuous grain boundary corrosion *** increased IGc sensitivity along the rolling direction could be related to the significantly flattened grains.

关键词： Al alloys Local corrosion Anisotropy Transmission electron microscopy(TEM) Electron backscattering diffraction(EBSD)

Sailing Through the Storm: A Strategic Review of cNOOc’s Unocal Acquisition

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Petroleum Science 2006年第4期3卷 10-14页

作者： chang Philip c. Wang Zhen University of calgary Canada china University of Petroleum Beijing 102249 China

cNOOc＇s 2005 attempt to take over Unocal was dubbed by some chinese media as ＂Acquisition of the century＂, as the $18.5 billion bid was the largest-ever overseas acquisition by a chinese company. cNOOc eventually withdrew its offer after chevron joined the bidding war and political sentiment in the U.S. congress became hostile. This paper analyzes the competitive bidding process and provides a strategic review. cNOOc＇s advantages in the acquisition included its international expertise, financing capability, access to the growing chinese market, and its willingness to retain Unocal staff after the merger. The main challenges were corporate governance, especially the understanding of the role of the board and the management of political risk in the U.S. In hindsight a pledge to divest Unocal＇s U.S. assets and not to give any impression of using subsidized loans could have helped deflect some political criticisms. Eventually, the U.S. government published the required energy security study in 2006 and it provided no support to the political concerns of the congress.

关键词： Strategy political risk cNOOc Unocal chevron

Base excision repair accessory factors in senescence avoidance and resistance to treatments

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cancer Drug Resistance 2022年第3期5卷 703-720页

作者： Elise Vickridge camila c.F.Faraco Alain Nepveu Goodman cancer Institute McGill University1160 Pine avenue WestMontrealQuebec H3A 1A3Canada Departments of Biochemistry McGill University1160 Pine avenue WestMontrealQuebec H3A 1A3Canada Medicine McGill University1160 Pine avenue WestMontrealQuébec H3A 1A3Canada Oncology McGill University1160 Pine avenue WestMontrealQuébec H3A 1A3Canada

cancer cells,in which the RAS and PI3K pathways are activated,produce high levels of reactive oxygen species(ROS),which cause oxidative DNA damage and ultimately cellular *** process has been documented in tissue culture,mouse models,and human pre-cancerous *** this context,cellular senescence functions as a tumour suppressor *** rare cancer cells,however,manage to adapt to avoid senescence and continue to *** well-documented mode of adaptation involves increased production of antioxidants often associated with inactivation of the KEAP1 tumour suppressor gene and the resulting upregulation of the NRF2 transcription *** this review,we detail an alternative mode of adaptation to oxidative DNA damage induced by ROS:the increased activity of the base excision repair(BER)pathway,achieved through the enhanced expression of BER enzymes and DNA repair accessory *** proteins,exemplified here by the cUT domain proteins cUX1,cUX2,and SATB1,stimulate the activity of BER *** ensued accelerated repair of oxidative DNA damage enables cancer cells to avoid senescence despite high ROS *** a by-product of this adaptation,these cancer cells exhibit increased resistance to genotoxic treatments including ionizing radiation,temozolomide,and ***,considering the intrinsic error rate associated with DNA repair and translesion synthesis,the elevated number of oxidative DNA lesions caused by high ROS leads to the accumulation of mutations in the cancer cell population,thereby contributing to tumour heterogeneity and eventually to the acquisition of resistance,a major obstacle to clinical treatment.

关键词： Base excision repair reactive oxygen species DNA repair accessory factor oxidative DNA damage resistance to treatment tumour heterogeneity acquisition of resistance

Energy coupling mechanism of FO in a rotary ATP synthase:a model update

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Biophysics Reports 2019年第2期5卷 61-64页

作者： Xuejun c.Zhang Min Liu National Laboratory of Biomacromolecules CAS Center for Excellence in Biomacromolecules Institute of Biophysics Chinese Academy of Sciences college of Life Science University of Chinese Academy of Sciences

INTRODUcTION In nearly all living cells, rotary ATP synthases of the F1 FOfamily are essential to inter-conversing of energy between the transmembrane electrochemical potential and the ATP form（Boyer 1997）. During ATP synthesis,the FOsector of the ATP synthase machinery converts the electrochemical energy of either protons or sodium ions into mechanical energy of a rotor; in turn, this energy is converted into chemical energy of ATP by the F1sector（Gruber et al. 2014; Nakamoto et al. 2008）.

关键词： Energy coupling Mechanism Proton Wire Unidirectional Rotation Half channel Proton Load

Physico-mechanical characterization of polyurethane foam dressings containing natural polyols

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Asian Journal of Pharmaceutical Sciences 2016年第1期11卷 114-115页

作者： Nantaporn Namviriyachote Kitipun Manosittisak Garnpimol c.Ritthidej Department of Pharmaceutics and Industrial Pharmacy Faculty of Pharmaceutical SciencesChulalongkorn UniversityBangkok 10330Thailand Bangkok Botanica co. Ltd.Bangkok 10600Thailand

Advanced wound dressings are replaced traditional dressings in order to provide appropriate environment for healing and also to promote cell migration[1].The key characteristics of wound dressings are non-toxic,highly absorbed,air permeable,biocompatible and have good mechanical properties[2].Due to providing moist environment and also protecting maceration at the wound edge area,foam dressings are used in various clinical applications[3].They are mostly prepared from polyurethane between polyols and isocyanate polymerization.

关键词： Polyurethane foam Natural polyols Starch Physico-mechanical properties

HAMILTONIANS WITH TWO DEGREes OF FREEDOM ADMITTING A SINGLEVALUED GENERAL SOLUTION

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Analysis in Theory and Applications 2005年第2期21卷 188-200页

作者： R.conte M.Musette c.Verhoeven cEA-Saclay Vrije UniversiteitVrije Universiteit FranceBelgiumBelgium

Following the basic principles stated by Painlevé, we first revisit the process of selecting the admissible time-independent Hamiltonians H = （p1^2 ＋ p2^2）/2 ＋ V（q1, q2） whose some integer power qj^nj （t） of the general solution is a singlevalued function of the complez time t. In addition to the well known rational potentials V of Hénon-Heiles, this selects possible cases with a trigonometric dependence of V on qj. Then, by establishing the relevant confluences, we restrict the question of the explicit integration of the seven （three “cubic” plus four “quartic”） rational Hénon-Heiles cases to the quartic cases. Finally, we perform the explicit integration of the quartic cases, thus proving that the seven rational cases have a meromorphic general solution explicitly given by a genus two hyperelliptic function.

关键词： two degree of freedom Hamiltonians Painlevé test Painlevé property Hdnon-Heiles Hamiltonian hyperelliptic

Steady State creep Rate Equation of Inconel 718 Superalloy

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Journal of Materials Science & Technology 1989年第2期5卷 79-84页

作者：韩雅芳 M.c.chaturvedi Institute of Aeronautical Materials Beijing China. Department of Mechanical Engineering University of Manitoba Canada.

The steady state creep rate equdtion of a nickel base superalloy Inconel 718, strengthened by coherent ordered disc-shaped bct γ^(11) phase and coherent spherical fcc γ~1 phase precipitates, has been established in the stress and temperature ranges of 620-840 MN m^(-2) and 853-943K, respecti- vely. constant stress tensile creep tests were used to medsure the values of steady state creep rate, ε_s, and the consecutive stress reduction method was used to measure the back stress during creep deformation. The values of effective stress exponent, n_e, were detemined from the slopes of the lgε_s vs. lg(σ_a-σ_0)/G plots. The effect of grain size, d, on steady state creep rdte has been also studied in this investigation, and the grain size sensitive exponents m were detemined from the slopes of lgε_s vs. lg(b/d) plots. The creep rate equations of Inconel 718, in the above stress and temperature ranges, have been proposed to be ε_s=1.6×10^(-5)(D_1Gb/KT) (b/d )^(0.19)[(σ_a-σ_0)/G]^(1.35) in diffusional creep region, and ε_s =75(D_1Gb/KT) (b/d)^(-0.42)[(σ_a-σ_0)/G]^(5.5) in dislocation power law creep region.

关键词： Inconel 718 steady state creep creep rate equation

Antifungal effects of Ocimum Kilimandscharicum oil on Aspergillus flavus Infecting Maize after Harvest

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Studies in Fungi 2021年第1期6卷 288-298页

作者： Kaguchia SM Birgen JK Lang’at-Thoruwa c Akwa TE Department of Plant Sciences Kenyatta UniversityNairobiKenya Department of chemistry Kenyatta UniversityNairobiKenya Department of Biochemistry Microbiology and Biotechnology Kenyatta UniversityNairobiKenya

Maize is consumed throughout the year in *** facilities of Maize vary with the economic status of the *** resource producers are likely to have unsuitable storage facilities whose conditions may predispose stored maize to post-harvest fungal *** most frequently encountered fungus in stored maize is Aspergillus flavus which produces aflatoxins that causes teratogenic,carcinogenic,mutagenic and hepatotoxic *** are used to control post-harvest fungi,but these have health *** an alternative safe method is the use of plant-based products which have anti-fungal *** study was therefore designed to evaluate growth inhibitory effects of Ocimum kilimandscharicum oil on Aspergillus *** leaves were collected from the plants growing naturally in Ruiru in Kiambu county,and the leaves were air dried in a shed,and oil was extracted through hydro-distillation.A total of 80 kg of threshed stored maize collected from randomly selected farms in Murang’a county were used to isolate Aspergillus *** growth experiments were done on PDA amended with different concentrations of the ***(pccurred at oil concentration of 3.33 ul/***,concentrations above 6.67ul/ml totally inhibited the growth of the ***,significantly(parge zones of inhibition were observed in the highest concentration of 400 ul/*** the results,it can be concluded that *** oil acts against Aspergillus flavus and is a potential source for developing an antifungal *** is recommended that the efficacy of this oil needs to be tested on other post-harvest fungi.

关键词： Aflatoxins Kenya Mycelia inhibition post harvest fungi storage conditions

Long-term stabilization of metastatic melanoma with sodium dichloroacetate

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World Journal of clinical Oncology 2017年第4期8卷 371-377页

作者： Akbar Khan Doug Andrews Jill Shainhouse Anneke c Blackburn Medicor cancer centres Inc Insight Naturopathic clinic the John curtin School of Medical Research the Australian National University

Sodium dichloroacetate(DcA) has been studied as a metabolic cancer therapy since 2007, based on a publication from Bonnet et al demonstrating that DcA can induce apoptosis(programmed cell death) in human breast, lung and brain cancer cells. classically, the response of cancer to a medical therapy in human research is measured by Response Evaluation criterial for Solid Tumours definitions, which define "response" by the degree of tumour reduction, or tumour disappearance on imaging, however disease stabilization is also a beneficial clinical outcome. It has been shown that DcA can function as a cytostatic agent in vitro and in vivo, without causing apoptosis. A case of a 32-year-old male is presented in which DcA therapy, with no concurrent conventional therapy, resulted in regression and stabilization of recurrent metastatic melanoma for over 4 years' duration, with trivial side effects. This case demonstrates that DcA can be used to reduce disease volume and maintain longterm stability in patients with advanced melanoma.

关键词： Dichloroacetate cancer BRAF Melanoma cytostatic

Studies on the seasonal variations in the proximate composition of ascidians from the Palk Bay,Southeast coast of India

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Asian Pacific Journal of Tropical Biomedicine 2012年第10期2卷 793-797页

作者： Ananthan G Karthikeyan MM Selva Prabhu A Raghunathan c centre of Advanced Study in Marine Biology Faculty of Marine SciencesAnnamalai University Zoological Survey of India Andaman and NicobarRegional Station.1Horticulture RoadHaddoPort Blair744102

Objective:To investigate the seasonal fluctuations of the proximate composition of the ascidians ***:The moisture content was estimated by drying 1 g of fresh tissue at a constant temperature at 105(?)for 24 *** loss of weight was taken as moisture *** total protein was estimated using the Biuret *** total carbohydrate in dried sample was estimated spectrophotometrically following the phenol-sulphuric acid *** lipid in the dried sample tissue was gravimetrically estimated following the chloroform-methanol mixture *** content was determined gravimetrically by incinerating 1 g dried sample in muffle furnace at about 550℃for 6 h and results are expressed in ***:It was found very difficult to compare the monthly variations,as all the ten species,exhibited wide fluctuations in their proximate *** the sake of convenience,average seasonal values were calculated by summing the monthly ***:The proximate composition of the 10 commonly available ascidians showed high nutritive value and hence these groups especially solitary ascidians can be recommended for human consumption in terms of pickles,soup,curry and others after ensuring the safety of consumers.

关键词： Ascidians Biochemical composition Seasonal variations proximate composition