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j.urnal of Magnesium and Alloys 2023年第2期11卷 706-719页

作者： G.Garces j.Medina P.perez A.Stark N.Schell P.Adeva Department of Physical Metallurgy CSICAvenida Gregorio del Amo 8Madrid E-28040Spain Institute of Materials Physics Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany

The load partitioning between the magnesium and titanium phases in an extruded Mg-15%Ti(vol.%) composite from room temperature up to 300 ℃ using synchrotron radiation diffraction during in-situ compression tests. During compression, the magnesium matrix composite deforms mainly by the activation of the extension twinning system up to 200 ℃. The volume fraction of twins increases with the plastic strain but decrease with the compression temperature. Hard titanium particles bear an additional load transferred by the soft magnesium matrix from room temperature up to 300 ℃. This effect is amplified after yield stress during plastic deformation. Additionally, twins within magnesium grains behaves as an additional reinforcement at low temperature(below 200 ℃) inducing an increase in the work hardening of the composite.

关键词： Magnesium alloys In-situ synchrotron radiationdiffraction Plasticity Precipitation Dislocationslip Twinning

Effect of inductively coupled plasma surface treatment on silica gel and mesoporous MCM-41 particles

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Plasma Science and Technology 2018年第6期20卷 104-113页

作者： j.A j.AREZ-MORENO U CHACON-ARGAEZ j.BARRON-ZAMBRANO C CARRERA-FIGUEIRAS P QUINTANA-OWEN W TALAVERA-PECH Y perez-PADILLA A AVILA-ORTEGA facultad de ingeniería química-uady periférico norte kilómetro 33.5col.chuburna de hidalgo inn C.P. 97203 Mérida Yucatan México centro de investigación y de estudios avanzados del ipn-unidad mérida km.6 antigua carretera a progreso apdo. Postal 73 Cordemex 97310 Méfida Yucatán México

Silica gel and MCM-41 synthesized mesoporous materials were treated with either oxygen（O_2）,hexamethyldisiloxane（HMDSO） and organic vapors like ethanol（Et OH）,and acrylonitrile（AN）inductive *** radiofrequency power for the modification was fixed to 120 W and30 min,assuring a high degree of organic ionization energy in the *** surface properties were studied by infrared spectroscopy（FTIR）,scanning electron microscopy,x-ray photoelectron spectroscopy and dynamic light scattering technique was used for characterizing size *** the silica and MCM-41 particles were modified by AN and HMDSO plasma gases,the surface morphology of the particles was changed,presenting another color,size or *** contrast,the treatments of oxygen and Et OH did not affect the surface morphology of both particles,but increased the oxygen content at the surface bigger than the AN and HMDSO plasma *** this study,we investigated the influence of different plasma treatments on changes in morphology and the chemical composition of the modified particles which render them a possible new adsorbent for utilization in sorptive extraction techniques for polar compounds.

关键词： silica MCM-41 nanoparticles plasma treatment

Bile-acid-induced cell inj.ry and protection

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World j.urnal of Gastroenterology 2009年第14期15卷 1677-1689页

作者： Maria j.perez Oscar Briz Research Unit University Hospital of Salamanca Laboratory of Experimental Hepatology and Drug Targeting CIBERehd University of Salamanca E.D. 129 37007 Salamanca Spain

Several studies have characterized the cellular and molecular mechanisms of hepatocyte inj.ry caused by the retention of hydrophobic bile acids （BAs） in cholestatic diseases. BAs may disrupt cell membranes through their detergent action on lipid components and can promote the generation of reactive oxygen species that, in turn, oxidatively modify lipids, proteins, and nucleic acids, and eventually cause hepatocyte necrosis and apoptosis. Several pathways are involved in triggering hepatocyte apoptosis. Toxic BAs can activate hepatocyte death receptors directly and induce oxidative damage, thereby causing mitochondrial dysfunction, and induce endoplasmic reticulum stress. When these compounds are taken up and accumulate inside biliary cells, they can also cause apoptosis. Regarding extrahepatic tissues, the accumulation of BAs in the systemic circulation may contribute to endothelial inj.ry in the kidney and lungs. In gastrointestinal cells, BAs may behave as cancer promoters through an indirect mechanism involving oxidative stress and DNA damage, as well as acting as selection agents for apoptosis-resistant cells. The accumulation of BAs may have also deleterious effects on placental and fetal cells. However, other BAs, such as ursodeoxycholic acid, have been shown to modulate BA-induced inj.ry in hepatocytes. The maj.r beneficial effects of treatment with ursodeoxycholic acid are protection against cytotoxicity due to more toxic BAs; the stimulation of hepatobiliary secretion; antioxidant activity, due in part to an enhancement in glutathione levels; and the inhibition of liver cell apoptosis. Other natural BAs or their derivatives, such as cholyI-N- methylglycine or pharmacological properties. cholylsarcosine, interest owing have also aroused to their protective

关键词： Apoptosis Cholestasis Liver Necrosis Oxidative stress Ursodeoxycholic acid

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一种带混合进化机制的膜聚类算法

软件学报 2015年第5期26卷 1001-1012页

作者：彭宏蒋洋王军 Mario j.perez-j.MENEZ 西华大学无线电管理技术研究中心四川成都610039 西华大学电气信息学院四川成都610039 Research Group of Natural Computing University of Seville Sevilla Spain

膜计算(也称为P系统或膜系统)是一种新颖的分布式、并行计算模型.为了处理数据聚类问题,提出了一种采用混合进化机制的膜聚类算法.它使用了一个由3个细胞组成的组织P系统,为一个待聚类的数据集发现最优的簇中心.其对象表示候选的簇中心... 详细信息

膜计算(也称为P系统或膜系统)是一种新颖的分布式、并行计算模型.为了处理数据聚类问题,提出了一种采用混合进化机制的膜聚类算法.它使用了一个由3个细胞组成的组织P系统,为一个待聚类的数据集发现最优的簇中心.其对象表示候选的簇中心,并且这3个细胞分别使用了3种不同的进化机制:遗传算子、速度-位移模型和差分进化机制.然而,所使用的速度-位移模型和差分进化机制是结合了这个特殊膜结构和转运机制所提出的改进版本.这种混合进化机制能够增强系统中对象的多样性和改善收敛性能.在混合进化机制和转运机制控制下,这种膜聚类算法能够确定一个数据集的良好划分.所提出的膜聚类算法在3个人工数据集和5个真实数据集上被评估,并与k-means和几种进化聚类算法进行比较.统计显著性测试建立了所提出的膜聚类算法的优势.

关键词：膜计算 P系统组织P系统数据聚类膜聚类算法混合进化机制

Experimental and Data Fitting Guidelines for the Determination of Polymer Crystallization Kinetics

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Chinese j.urnal of Polymer Science 2022年第6期40卷 658-691页

作者： Ricardo Arpad perez-Camargo Guo-Ming Liu Du-j.n Wang Alej.ndro j.Muller Beij.ng National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China POLYMAT and Department of Polymers and Advanced Materials:Physics Chemistry and TechnologyFaculty of ChemistryUniversity of the Basque Country UPV/EHUDonostia-San Sebastián 20018Spain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain

The crystallization kinetics of semicrystalline polymers is often studied with isothermal experiments and analyzed by fitting the data with analytical expressions of the Avrami and Lauritzen and Hoffman(LH)*** correctly carry out the analysis,precautions in both experiments and data fitting should be ***,we systematically discussed the factors that influence the validity of the crystallization kinetics *** basic concepts and fundamentals of the Avrami and LH theories were introduced at ***,experimental protocols were discussed in *** clarify the impact of various experimental parameters,selected common polymers,i.e.,polypropylene and polylactide,were studied using various experimental techniques(i.e.,differential scanning calorimetry and polarized light optical microscopy).Common mistakes were simulated under conditions when non-ideal experimental parameters were ***,from a practical point of view,we show how to fit the experimental data to the Avrami and the LH theories,using an Origin■App developed by us.

关键词： Isothermal crystallization Avrami equation Lauritzen and Hoffman theory Thermal analysis Step-crystallization

rAL Effectors Drive Transcription Bidirectionally in Plants

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Molecular Plant 2017年第2期10卷 285-296页

作者： Li Wang Fabio C. Rinaldi Pallavi Singh Erin L. Doyle Zoe E. Dubrow Tuan Tu Tran Alvaro L. perez-Quintero Boris Szurek Adam j. Bogdanove Plant Pathology and Plant-Microbe Biology Section School of Integrative Plant Science Cornell University 334 Plant Science Building Ithaca NY 14853 USA Department of Biology Doane University 1014 Boswell Avenue Crete NE 68333 USA UMR Interactions-Plantes-Microorganismes-Environnement IRD-Cirad-Universite Montpellier Montpellier France

TAL effectors delivered by phytopathogenic Xanthomonas species are DNA-sequence-specific transcrip- tional activators of host susceptibility genes and sometimes resistance genes. The modularity of DNA recognition by TAL effectors makes them important also as tools for gene targeting and genome editing. Effector binding elements （EBEs） recognized by native TAL effectors in plants have been identified only on the forward strand of target promoters. Here, we demonstrate that TAL effectors can drive plant tran- scription from EBEs on either strand and in both directions. Furthermore, we show that a native TAL effector from Xanthomonas oryzae pv. oryzicola drives expression of a target with an EBE on each strand of its promoter. By inserting that promoter and derivatives between two reporter genes oriented head to head, we show that the TAL effector drives expression from either EBE in the respective orientations, and that activity at the reverse-strand EBE also potentiates forward transcription driven by activity at the forward-strand EBE. Our results reveal new modes of action for TAL effectors, suggesting the possibility of yet unrecognized targets important in plant disease, expanding the search space for off-targets of custom TAL effectors, and highlighting the potential of TAL effectors for probing fundamental aspects of plant transcription.

关键词： xanthomonas transcription activator-like effector bidirectional reporter enhancer element off-target

Lj.trasensitive H2S gas sensors based on p-type WS2 hybrid materials

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Nano Research 2018年第8期11卷 4215-4224页

作者： Georgies Alene Asrest j.se j. Baldovi Aron Dombovari Topias j.rvinen Gabriela Simone Lorite Melinda Mohl Andrey Shchukarev Alej.ndro perez Paz Lede Xian j.ri-Pekka Mikkola Anita Lloyd Spetz Heli j.ntunen Angel Rubio Krisztian Kordas Microelectronics Research Unit Faculty of Information Technology and Electrical Engineering University of Oulu P.O. Box 4S00FI-90014 Oulu Finland Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 149 22761 Hamburg Germany Nano-Bio Spectroscopy Group European Theoretical Spectroscopy Facifity (ETSF) Universidad del Pals Vasco CFM SCIC-UPV/EHU-MPC DIPC A venida Tolosa 72 20018 San Sebastian Spain Technical Chemistry Department of Chemistry Chemical-Biological Centre Umea University SE-90187 Umea Sweden School of Chemical Sciences and Engineering School of Physics and Nanotechnology Yachay Tech University Urcuquf Ecuador Industrial Chemistry & Reaction Engineering Department of Chemical Engineering Johan Gadolin Process Chemistry Centre AboAkademi University FI-20500 Abo-Turku Finland Sensor and Actuator Systems Department of Physics Chemistry and Biology Link~ping University SE-58183 LinkOping Sweden

Owing to their higher intrinsic electrical conductivity and chemical stability with respect to their oxide counterparts, nanostructured metal sulfides are expected to revive materials for resistive chemical sensor applications. Herein, we explore the gas sensing behavior of WS2 nanowire-nanoflake hybrid materials and demonstrate their excellent sensitivity （0.043 ppm-1） as well as high selectivity towards H2S relative to CO, NH~, H2, and NO （with corresponding sensitivities of 0.002, 0.0074, 0.0002, and 0.0046 pprn-1, respectively）. Gas response measurements, complemented with the results of X-ray photoelectron spectroscopy analysis and first-principles calculations based on density functional theory, suggest that the intrinsic electronic properties of pristine WS2 alone are not sufficient to explain the observed high sensitivity towards H2S. A maj.r role in this behavior is also played by O doping in the S sites of the WS2 lattice. The results of the present study open up new avenues for the use of transition metal disulfide nanomaterials as effective alternatives to metal oxides in future applications for industrial process control, security, and health and environmental safety.

关键词： ws nanowire nanoflake gas sensor H2S,O doping

Raman-IR vibrational and XRD characterization of ancient and modern mineralogy from volcanic eruption in Tenerife Island： Implication for Mars

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Geoscience Frontiers 2016年第4期7卷 673-681页

作者： E.A.Lalla G.Lopez-Reyes A.Sansano A.Sanz-Arranz j.Martinez-Frias j.Medina F.Rull-perez department of physics faculty of science university of la laguna san cristobal de la laguna santa cruz de tenerifeCP 38206 spain Unidad Asociada al Centro de Astrobiologfa CSIC-INTA Associated to the NASA Astrobiology Center-Instituto Nacional de Tecnica Aeroespacial Torrejon de ArdozCP 28850MadridSpain Department of Earth Dynamics and Observation lnstituto de Ceociencias IGEO-(CSIC-UCM)Facultad de Ciencias Geologicas.Ciudad UniversitariaCP 28040MadridSpain

A detailed vibrational Raman-lR spectroscopic and diffractional analyses have been performed on basalts from two locations from Tenerife Island：（1） the Arenas Negras volcano which belongs to the historical eruption not showing visible alteration and （2） Pillow Lavas zone from Anaga Massif which shows a clearly fluid-rock interaction caused by submarine alteration. These places have been extensively studied due to its similarity with the surface of Mars. The analysis is based on the mineral detection of selected samples by a Micro-Raman study of the materials. The complementary techniques have confirmed the mineralogy detected by the Raman measurement. The results show a volcanic environment behavior with primary phases like olivine, pyroxene, and feldsparj.lagioclase. Moreover, the presence of accessory minerals or secondary mineralization like phosphate, iron oxides, zeolite or carbonates shows the alteration processes on each outcrop. The variation in the crystallinity and amorphous phases is related to fluid-rock interaction caused by hydrothermal episodes and external weathering processes, which shows several analogies with the ancient volcanic activity from Mars.

关键词： Mars Volcanoes Terrestrial analog Raman spectroscopy Tenerife Island Mineralogy

Phonon imaging in 3D with a fibre probe

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Light(Science & Applications) 2021年第6期10卷 1007-1019页

作者： Salvatore La Cavera III Fernando perez-Cota Richard j.mith Matt Clark Optics and Photonics Group Faculty of EngineeringUniversity of NottinghamUniversity ParkNottingham NG72RDUK

We show for the first time that a single ultrasonic imaging fibre is capable of simultaneously accessing 3D spatial information and mechanical properties from microscopic *** novel measurement system consists of two ultrafast lasers that excite and detect high-frequency ultrasound from a nano-transducer that was fabricated onto the tip of a single-mode optical fibre.A signal processing technique was also developed to extract nanometric in-depth spatial measurements from GHz frequency acoustic waves,while still allowing Brillouin spectroscopy in the frequency ***-free and non-contact imaging performance was demonstrated on various polymer *** singular device is equipped with optical lateral resolution,2.5μm,and a depth-profiling precision of 45 nm provided by *** endoscopic potential for this device is exhibited by extrapolating the single fibre to tens of thousands of fibres in an imaging *** a device catalyses future phonon endomicroscopy technology that brings the prospect of label-free in vivo histology within reach.

关键词： fibre equipped acoustics

Effects of bixin in high-fat diet-fed-induced fatty liver in C57BL/6j.mice

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Asian Pacific j.urnal of Tropical Biomedicine 2016年第12期6卷 1015-1021页

作者： Rosa Martha perez Gutierrez Rita Valadez Romero Research Laboratory of Natural Products School of Chemical Engineering and Extractive IndustriesNational Polytechnic InstituteAv.Instituto Politecnico Nacional S/NUnidad Profesional Adolfo Lopez Mateos

Obj.ctive:To evaluate the anti-obesity activity of bixin(BIX) on C57BL/6j.mice which were fed a high-fat diet(HFD) and to determine the mechanism of this ***:C57BL/6j.mice were separately fed a high-calorie diet or a normal diet for 8weeks,then they were treated with BIX for another 13 *** administration for 13 weeks,the animals were *** adiposity,serum lipid level,and insulin resistance were *** addition,a histological assay of pancreas and liver,an evaluation of the inhibitory properties on pancreatic lipase,and a-amylase were ***:Administration of BIX significantly decreased the body weight gain,adipocyte size,fat pad weights,hepatic lipid levels in HFD-induced obese *** addition,reduced liver weight exhibited decreased serum leptin levels,malic enzyme,glucose-6-phosphate dehydrogenase,hepatic fatty acid synthase,aspartate aminotransferase,alanine aminotransferase and hepatic phosphatidate phosphohydrolase ***,superoxide dismutase,catalase,glutathione peroxidase,and glutathione levels were increased in hepatic *** also decreased lipid and carbohydrates absorption due to inhibition of pancreatic lipase and *** term supplementation of BIX significantly decreased hyperlipidemia,insulin resistance and glucose *** levels of hepatic steatosis and the islets of Langerhans appeared less shrunken in HFD-fed ***:The antiobesity effect of BIX appears to be associated at least in part,to its inhibitory effect on lipids and carbohydrate digestion enzymes such as pancreatic lipase,a-glucosidase,and *** results suggested that BIX also act as an antioxidant and may treat visceral obesity normalizing glucose levels,improving insulin resistance and increasing energy ***,achiote which has a main component,the carotenoid BIX,could be a viable food for the treatment of obesity and diabetes.

关键词： Bixa orellana Bixin Obesity Enzymes Metabolic disturbances Diabetic