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alcohol drinking and mammary cancer: pathogenesis and potential dietary pre.e.tive alternatives

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World Journal of Clinical Oncology 2014年第4期5卷 713-729页

作者： Gerardo Daniel castro José A castro Centro de Investigaciones Toxicológicas CITEDEF B1603ALO Villa Martelli province of Buenos Aires Argentina Instituto de Investigación e Ingeniería Ambiental Universidad Nacional de General San Martín B1650ANQ San Martín province of Buenos Aires Argentina

Alcohol consumption is associated with an increased risk of breast cancer, increasing linearly even with a moderate consumption and irrespectively of the type of alcoholic beverage. It shows no dependency from other risk factors like menopausal status, oral contraceptives, hormone replacement therapy, or genetic history of breast cancer. The precise mechanism for the effect of drinking alcohol in mammary cancer promotion is still far from being established. Studies by our laboratory suggest that acetaldehyde produced in situ and accumulated in mammary tissue because of poor detoxicating mechanisms might play a role in mutational and promotional events. Additional studies indicated the production of reactive oxygen species accompanied of decreases in vitamin e and GSH contents and of glutathione transferase activity. The resulting oxidative stress might also play a re.e.ant role in several stages of the carcinogenic process. There are reported in literature studies showing that plasmatic levels ofestrogens significantly increased after alcohol drinking and that the breast cancer risk is higher in re.e.tor eRpositive individuals. estrogens are known that they may produce breast cancer by actions on eR and also as chemical carcinogens, as a consequence of their oxidation leading to reactive metabolites. In this review we introduce our working hypothesis integrating the acetaldehyde and the oxidative stress effects with those involving increased estrogen levels. We also analyze potential pre.e.tive actions that might be accessible. There remains the fact that alcohol drinking is just one of the avoidable causes of breast cancer and that, at pre.e.t, the suggested acceptable dose for pre.e.tion of this risk is of one drink per day.

关键词： Alcohol ethanol Acetaldehyde Free radicals Mammary cancer Oxidative stress estrogens Polyphenols

Tree Age Affects Postharvest Attributes and Mineral Content in Amrapali Mango(Mangifera indica) Fruits

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Horticultural Plant Journal 2018年第2期4卷 55-61页

作者： MeeNA Nirmal Kumar ASreY ram Division of Food Science and Postharvest Technology ICAR-Indian Agriculture Research Institute

The study was carried out to investigate the effect of tree age on postharvest attributes and mineral content of Amrapali mango fruits. effect of 3 different tree ages(6, 18 and 30 years) on functional components, including the antioxidant activity(AOX), total phenols, total carotenoids,ascorbic acid and minerals like Ca, K, Mg, Fe, Zn, Cu, Mn and B along with total sugars, total soluble solids(TSS) and titratable acidity(TA),respiration rate, polygalacturonase(PG) and pectin methylesterase(PMe) activities in Amrapali cultivar were studied. With tree ageing total phenols, ascorbic acid and antioxidant activity decreased whereas total carotenoids increased. Ca diminished and K elevated with the tree age progression while, B, Fe, Cu, Zn, and Mn showed an indefinite pattern. Total soluble solids and total sugars were recorded higher in 18 year old tree fruits. Fruit respiration rate, polygalacturonase and pectin methylesterase activities showed an upward trend with tree ageing. The study indicates that fruit produced from middle age group mango orchard(18 year old) suits to the require.e.t of consumers as well as industry.

关键词： mango(Mangifera indica) tree age functional parameter mineral

Quick Line Outage Identification in Urban Distribution Grids via Smart Meters

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CSee Journal of Power and energy Systems 2022年第4期8卷 1074-1086页

作者： Yizheng Liao Yang Weng Cin-Woo Tan ram Rajagopal Department of Civil and environmental engineering Stanford UniversityStanfordCA94305USA School of electrical Computingand Energy EngineeringArizona State UniversityTempeAZ85287USA

The growing integration of distributed energy resources(DeRs)in distribution grids raises various reliability issues due to DeR's uncertain and complex *** large-scale DeR penetration in distribution grids,traditional outage detection methods,which rely on customers report and smart meters'“last gasp”signals,will have poor performance,because re.e.able generators and storage and the mesh structure in urban distribution grids can continue supplying power after line *** address these challenges,we propose a datadriven outage monitoring approach based on the stochastic time series analysis with a theoretical ***,we prove via power flow analysis that dependency of time-series voltage measure.e.ts exhibits significant statistical changes after line *** makes the theory on optimal change-point detection suitable to identify line ***,existing change point detection methods require post-outage voltage distribution,which are unknown in distribution ***,we design a maximum likelihood estimator to directly learn distribution parameters from voltage *** prove the estimated parameters-based detection also achieves optimal performance,making it extre.e.y useful for fast distribution grid outage ***,since smart meters have been widely installed in distribution grids and advanced infrastructure.e.g,PMU)has not widely been available,our approach only requires voltage magnitude for quick outage *** results show highly accurate outage identification in eight distribution grids with 17 configurations with and without DeRs using smart meter data.

关键词： Power distribution network outage detection outage identification voltage measure.e.t change point detection graphical model

electron Paramagnetic resonance and Optical Absorption of VO2＋ Doped Bis （glycinato） Mg （II） Monohydrate Single Crystals

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Chinese Physics Letters 2010年第1期27卷 238-241页

作者： Prashant Dwivedi ram Kripal Santwana Shukla Department of Physics Kali Charan Nigam Institute of Technology Banda (U.P.) 210001 India ePR Laboratory Department of Physics University of Allabad Allahabad 211002 India

We investigate the electron paramagnetic resonance （ePR） of VO2＋ ions in bis （glycinato） Mg （II） monohydrate single crystals at room temperature. Detailed ePR analysis indicates the pre.e.ce of only one VO2＋ site. The vanadyl complexes are found to take up the substitutional position. The angular variation of the ePR spectra in three planes a＊b, bc and ca＊ are used to determine principal g and A tensors. The values of spin Hamiltonian parameters are gx= 2.1447× 10-4, gy= 1.9974×10-4, gz= 1.9131×10-4, Ax= 49×10-4, Ay= 60×10-4, Az= 82×10-4 cm-1. The optical absorption study is also carried out at room temperature and absorption bands are assigned to various transitions. The theoretical band positions are obtained using energy expressions and a good agreement is found with the experimental data. By correlating ePR and optical data, different molecular orbital coefficients are.e.aluated and the nature of bonding in the crystal is discussed.

关键词： Temperature Data Uses Absorption Timing Time

Geomorphic indices and relative tectonic uplift in the Guerrero sector of the Mexican forearc

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Geoscience Frontiers 2017年第4期8卷 885-902页

作者： Krzysztof Gaidzik María Teresa ramírez-Herrera Laboratorio Universitario de Geofísica Ambiental & Instituto de Geografía Universidad Nacional Autónoma de MéxicoCiudad Universitaria Berkeley Seismological Laboratory Department of Earth and Planetary ScienceUniversity of California Berkeley

Tectonically active areas,such as forearc regions,commonly show contrasting relief,differential tectonic uplift,variations in erosion rates,in river incision,and in channel gradient produced by ongoing tectonic ***,information on the tectonic activity of a defined area could be derived via landscape *** study uses topography and geomorphic indices to extract signals of ongoing tectonic deformation along the Mexican subduction forearc within the Guerrero *** this purpose,we use field data,topographical data,knickpoints,the ratio of volume to area（Rva）.the stream-length gradient index（St）,and the normalized channel steepness index（k_（sn））.The results of the applied landscape analysis re.e.l considerable variations in relief,topography and geomorphic indices values along the Guerrero sector of the Mexican subduction *** argue that the reported differences are indicative of tectonic deformation and of variations in relative tectonic uplift along the studied forearc.A significant drop from central and eastern parts of the study area towards the west in values of R_（VA）（from ~500 to^300）,St（from ~500 to ca.400）,maximum St（from ~1500-2500 to ~ 1000） and k_（sn）（from ~150 to ~100） denotes a decrease in relative tectonic uplift in the same *** suggest that applied geomorphic indices values and forearc topography are independent of climate and *** mechanisms responsible for the observed variations and inferred changes in relative forearc tectonic uplift call for further studies that explain the physical processes that control the forearc along strike uplift variations and that determine the rates of *** proposed methodology and results obtained through this study could prove useful to scientists who study the geomorphology of forearc regions and active subduction zones.

关键词： relative tectonic uplift Forearc Active tectonics Geomorphic index Drainage network Mexican subduction zone

effect of sintering temperature on phase evolution of Al86Ni6Y4.5Co2La1.5 bulk amorphous composites synthesized via mechanical alloying and spark plasma sintering

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Progress in Natural Science:Materials International 2019年第1期29卷 32-40页

作者： Ashutosh Sahu ram Sajeevan Maurya Tapas Laha Department of Metallurgical and Materials engineering Indian Institute of Technology Department of Metallurgical and Materials engineering National Institute of Technology

Al86Ni6Y4.5Co2La1.5amorphous powders were synthesized by mechanical alloying for 200 h. Subsequent consolidation was performed via spark plasma sintering in the temperature range of 250 ℃ to 500 ℃ at the pressure of 500 MPa. The role of viscous flow on densification was investigated by studying the viscosity change of the amorphous phase at different consolidation temperatures. The decrease in viscosity at higher sintering temperatures resulted in better particle bonding and densification of consolidated samples. The formation of only FCC Al was observed in the consolidated samples at sintering temperatures ≤ 300 ℃ and the intermetallic phases formed at temperatures ≥ 400 ℃. The mechanical properties of the bulk samples were measured by Vickers microhardness and nanoindentation tests. The testing results showed that the average values of microhardness, nanohardness and elastic modulus of the sample consolidated at 500 ℃ were 3.06 ± 0.14 GPa,4.85 ± 1.14 GPa and 89.53 ± 9.25 GPa, respectively. The increase in hardness and elastic modulus of the higher temperature consolidated samples is attributed to the improvement in particle bonding, densification and distribution of various hard intermetallic phases in the amorphous matrix.

关键词： Al based glassy alloy Mechanical alloying Spark plasma sintering Intermetallic phase Viscosity

Displacement Field due to Nonuniform Slip along a Long Dip-Slip Fault in Two Welded Half-Spaces

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Journal of earth Science 2012年第6期23卷 864-872页

作者： Sunita Rani Neeru Bala ram Chander Verma Department of Mathematics Guru Jambheshwar University of Science and TechnologyHisar 125001India

The solution of static deformation of two homogeneous, isotropic, and perfectly elastic half-spaces in welded contact due to a long dip-slip fault with uniform slip is well known. The aim of the pre.e.t article is to obtain the static deformation of two homogeneous, isotropic, and perfectly elastic half-spaces in welded contact due to nonuniform slip along a long dip-slip fault. The fault is vertical and lies entirely in the lower half-space, extending up to the interface. Four slip profiles are considered： lin- ear, parabolic, elliptic, and cubic. Closed-form expressions for the elastic residual field have been ob- tained for the different slip profiles. The displacement field due to four nonuniform slip profiles is com- pared with the displacement field due to uniform slip. For comparison, we have assumed the source potency for different slip profiles to be the same, which is achieved by taking the fault slip at the inter- face constant and varying the fault width. It is found that the displacement field varies significantly at the fault width rather than at the interface. Moreover, uniform slip along the fault makes the edges singular. This singularity at the lower edge is not pre.e.t in the case of nonuniform slip along a long dip-slip fault.

关键词： nonuniform slip two welded half-spaces dip-slip fault displacement field.

Comparative study of travelling-wave and numerical solutions for the coupled short pulse (CSP) equation

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Chinese Physics B 2013年第5期22卷 60-66页

作者： Vikas Kumar R. K. Gupta ram Jiwari School of Mathematics and Computer Applications Thapar University

The Lie symmetry analysis is performed for the coupled short plus （CSP） equation. We derive the infinitesimals that admit the classical symmetry group. Five types arise depending on the nature of the Lie symmetry generator. In all types, we find reductions in terms of system of ordinary differential equations, and exact solutions of the CSP equation are derived, which are compared with numerical solutions using the classical fourth-order Runge-Kutta scheme.

关键词： coupled short pulse (CSP) equation Lie symmetric analysis Runge-Kutta scheme exact solutions

resveratrol as an inductor of autophagy: is there a unique pathway of activation?

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Neural re.e.eration re.e.rch 2021年第1期16卷 101-103页

作者： Narayana Pineda-ramírez Penélope Aguilera Laboratorio de Patología Vascular Cerebral.Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez Ciudad de MéxicoMéxico

Autophagy is a process of cellular degradation for the removal of damaged components and eventual recycling of the resulting molecules that help to the maintenance of cellular *** this pathway,proteins with relatively long half-life and whole organelles(e.g.,mitochondria,peroxisomes,and ribosomes)are degraded in the cytoplasm for the continuous turnover of cellular structures to facilitate their ***,the beneficial effect of autophagy goes beyond cellular“cleaning”and resides to a large extent on its ability to recycle cell components back into the ***,autophagy is a fundamental mechanism to regulate cellular functions,including DNA repair,proliferation,differentiation,embryonic development,and the immune response.

关键词： homeostasis activation autophagy