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Chiral Current in a Graphene Battery

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Journal of Electromagnetic Analysis and Applications 2012年第10期4卷 426-431页

作者： hector torres-silva Diego torres Cabezas Escuela de Ingeniería Eléctrica Electrónica Universidad de Tarapacá Arica Chile Modernización y Gobierno Electrónico Ministerio Secretaría General de la Presidencia Santiago Chile.

We review the formulation of graphene’s massless Dirac equation, under the chiral electromagnetism approach, hopefully demystifying the material’s unusual chiral, relativistic, effective theory. In Dirac’s theory, many authors replace the speed of light by the Fermi velocity, in this paper we deduce that in graphene the Fermi velocity is obtained from the connection between the electromagnetic chirality and the fine structure constant when the electric wave E is quasi parallel to the magnetic wave H. With this approach we can consider the properties of electric circuits involving graphene or Weyl semimetals. The existence of the induced chiral magnetic current in a graphene subjected to magnetic field causes an interesting and unusual behavior of such circuits. We discuss an explicit example of a circuit involving the current generation in a “chiral battery”. The special properties of this circuit may be utilized for creating “chiral electronic” devices.

关键词： Chiral Dirac Battery Grapheme Weyl Semimetal

Chiral Seismic Attenuation with Acoustic Metamaterials

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Journal of Electromagnetic Analysis and Applications 2013年第1期5卷 10-15页

作者： hector torres-silva Diego torres Cabezas 不详

We study the analogy between the linear elasticity theory equations and classical Maxwell equation with chiral effects and we propose a new method of an earthquake-resistant design to support conventional aseismic designs using acoustic metamaterials. We suggest a simple and practical method to reduce the amplitude of a seismic wave exponentially. Our device is like an attenuator of a chiral seismic wave. Constructing a cylindrical shell-type waveguide that creates a stop-band for the chiral seismic wave, we can convert the wave into an evanescent wave for some frequency range without touching the building we want to protect.

关键词： Chiral Metamaterial Seismic Wave Acoustic Properties

Convective Schrodinger Equation:Insights on the Potential Energy’s Role to Wave Particle Decay

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Journal of Electromagnetic Analysis and Applications 2015年第9期7卷 225-232页

作者： Altair S.de Assis hector torres-silva Goran T.Marklund Universidade Federal Fluminense(IM-GMA) NiteroiBrasil Universidad de Tarapaca AricaChile Kungliga Tekniska Hogskolan—KTH StockholmSweden

In this paper, we coupled the Quantum Mechanics conventional Schrödinger’s equation, for the particles, with the Maxwell’s wave equation, in order to study the potential’s role on the conversion of the electromagnetic field energy to mass and vice versa. We show that the dissipation (“conductivity”) factor and the particle implicit proper frequency are both related to the potential energy. We have also derived a new expression for the Schrödinger’s Equation considering the potential energy into this equation not as an ad hoc term, but also as an operator (Hermitian), which has the scalar potential energy as a natural eigenvalue of this operator.

关键词： Schrodinger’s Equation Klein-Gordon’s Equation Maxwell’s Wave Equation Convection Displacement Current

Tribological performance of iron- and nickel-base self-lubricating claddings containing metal sulfides at high temperature

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Friction 2022年第12期10卷 2069-2085页

作者： hector torres Tugce CAYKARA Jens HARDELL Janne NURMINEN Braham PRAKASH Manel RODRIGUEZ RIPOLL AC2T research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Department of Applied Physics and Mechanical Engineering LuleåUniversity of TechnologyLuleå97187Sweden Castolin Eutectic GmbH Gutenbergstraße 10Kriftel 65830Germany Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Iron-based coatings with the incorporation of solid lubricants have been prepared by means of laser cladding,in an effort to control friction and decrease tool wear at high temperatures during metal forming *** choice of a Fe-based powder has been considered advantageous,as it can lead to decreased costs compared to nickel-based claddings previously studied by the authors,in addition to having a lower environmental *** particular,the incorporation of transition metal dichalcogenides such as MoS_(2) as precursors leads to the encapsulation of silver in Fe-based self-lubricating claddings,resulting in a uniform distribution of the soft metal across the thickness of the *** tribological evaluation of the claddings at high temperatures shows that the addition of lubricious compounds leads to lower friction at room temperature and significantly decreased wear up to 600℃ compared to the unmodified iron-based reference alloy,although higher than similar self-lubricating Ni-based *** order to cast light into these observed differences,the corresponding microstructures,phase composition,and self-lubricating mechanisms have been studied and compared for Fe-and Ni-based claddings having both of them the addition of silver and MoS_(2).The results suggest a key role of the formation of protective tribolayers on the counter body during high temperature sliding *** simulation of the phase evolution during solidification reveals that the formation of different chromium-and nickel-based metal sulfides in Fe-and Ni-claddings during laser cladding by the decomposition of MoS_(2) plays a key role in determining their tribological behaviour at high temperatures.

关键词： high temperature laser cladding self-lubrication metal forming chromium sulphide MoS_(2)

Secreted protein acidic and rich in cysteine(SPARC)induces epithelial-mesenchymal transition,enhancing migration and invasion,and is associated with high Gleason score in prostate cancer

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Asian Journal of Andrology 2019年第6期21卷 557-564页

作者： Fernanda Lopez-Moncada Maria Jose torres Enrique A Castellon hector R Contreras Department of Basic and Clinic Oncology Faculty of Medic泊eUniversity of ChileSantiago 8389100Chile

Secreted protein acidic and rich in cysteine(SPARC)is a matricellular protein highly expressed in bone tissue that acts as achemoattractant factor promoting the arrival of prostate cancer(PCa)cells to the bone ***,the contribution of SPARCduring the early stages of tumor progression remains *** this study,we show that SPARC is highly expressed in PCa tissueswith a higher Gleason *** stable knockdown and overexpression of SPARC in PC3 and LNCaP cells,respectively,here wedem on strate that en doge nous SPARC induces the epithelial-mesenchymal tran sition(EMT),decreasing E-cadheri n and cytokeratin18 and increasing N-cadheri n and vime ***,SPARC in duces the expression of EMT regulatory tran scription factors Snailfamily transcriptional repressor 1(Snail),Snail family transcriptional repressor 2(Slug),and zinc finger E-box binding homeobox 1(Zeb1).In addition,SPARC knockdown in PC3 cells decreases migration and invasion in vitro,without modifying cell *** results indicate that SPARC might facilitate tumor progression by modifying the cellular phenotype in cancer cells.

关键词： epithelial-mesenchymal transition invasion migration prostate cancer secreted protein acidic and rich in cysteine(SPARC)

Interpreting Morphologically Homogeneous(Paleo-)Populations as Ecological Species Enables Comparison of Living and Fossil Organism Groups,Exemplified by Nummulitid Foraminifera

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Journal of Earth Science 2022年第6期33卷 1362-1377页

作者： Johann Hohenegger Ana Ivis torres-silva Wolfgang Eder Institute for Paleontology University of Vienna1090ViennaAustria

Morphologically homogeneous groups,either living populations or fossil paleo-populations,must be regarded as ecological species,independent of their molecular genetic resemblance in living *** is always expressed during development by structure genes initiated from a network of regulator genes acting at different times and intensities,additionally being subjected to epigenetic ***,homogeneous populations influenced by the environment represent species better than the reproduction(biological species)or molecular-genetic approach using ancestral sequences like *** and fossil representatives of nummulitid foraminifera were chosen to demonstrate complete reconstruction of morphology using metrical growth-invariant and growth-independent *** these characters,6 models were established to define ecological species in living and fossil ***,a distinction between evolutionary and environmental effects in fossil forms was possible using discriminant analysis showing characters that are responsible for differentiating between evolutionary and environmental trends.

关键词： ecological species growth-invariant metrical characters morphology homogeneity nummulitids

Experience with the surgical treatment of hepatic hydatidosis: Case series with follow-up

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World Journal of Gastroenterology 2010年第26期16卷 3305-3309页

作者： hector Losada Morales Luis Burgos San Juan Jorge silva Abarca Cesar Muoz Castro Department of Surgery Universidad de La Frontera Hepato Pancreatic and Biliary Surgery Hospital Hernán Henríquez Aravena Department of Surgery Clínica Alemana de Temuco

AIM: To describe patient characteristics and the results of surgical treatment for hepatic hydatidosis (HH) in the Hospital Hernán Henríquez Aravena from December 2001 to March 2005. METHODS: Subjects older than 16 years with suspected HH were included based on the clinical picture and radiological studies. Variables examined included clinical and laboratory aspects, outcome, features of the parasite and surgical aspects. Descriptive statistics were used, calculating central tendency, dispersion and extreme tendency. RESULTS: The series was comprised of 122 patients, with an average age of 44 ± 16.9 years. The most frequently used surgical technique was subtotal cys-tectomy in 90% of the patients, followed by hepatic resection (hepatectomy, segmentectomy and subsegmentectomy) in 5%. In 2%, a combination of subtotal cystectomy and segmentectomy was performed. In addition, 28% of the series presented complications in the postoperative period and mortality was 2%. CONCLUSION: The most frequently used surgical technique for HH was subtotal cystectomy and the morbidity and mortality rates in this Chilean series are comparable to other national and international series.

关键词： Echinococcosis of liver Surgery Cases series Mortality Morbidity

Comparative stability analyses of traditional and selective room-and-pillar mining techniques for sub-horizontal tungsten veins

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 1-8页

作者： Vidal Felix Navarro torres Carlos Dinis da Gama Matilde Costa e silva Paula Falcao Neves Qiang Xie Mining and Geo-resources Engineering Department of IST Technical University of Lisbon 1049-001 Portugal Faculty of Civil Engineering Chongqing University Chongqing 400045 China

The stability and productivity concerning a modification on the traditional room and pillar for a new selective technique at the Portuguese Panasqueira Mine have been *** traditional room-and-pillar stoping uses 5.0-m wide rooms with 3.0 m×3.0 m pillars,while the selective room-and-pillar mining technique consists in stoping with rooms of 4.0 m wide and pillars of 4 m×4 m with a subsequent selective cutting of the quartz veins at the mid pillar of approximately 0.5 m high,to obtain a pillar section with an area of 3.0 m×3.0 *** stability and productivity analyses indicate that the selective technique obtains smaller average pillar safety factor,more rock mass displacement,more extraction and selectivity ratios,and ore grade improvement,compared with the traditional *** results show that the selective technique is also more *** proposed selective room-and-pillar mining technique is applicable to any sub-horizontal narrow quartz veins with wolfram,gold,*** as the famous La Rinconada gold mine in the Peruvian Andes.

关键词： mines and mining tungsten deposits productivity stability stoping

Impact of the adherence to medical treatment on the main urinary metabolic disorders in patients with kidney stones

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Asian Journal of Urology 2021年第3期8卷 275-279页

作者： Braulio Omar Manzo Jose David Cabrera Esteban Emiliani hector Manuel Sanchez Brian Howard Eisner Jose Ernesto torres Urology Department Hospital Regional de Alta Especialidad del BajioBlvd.Milenio#130Col.San Carlos la RonchaLeonGuanajuatoMexico Urology Department Fundacion PuigvertUniversidad Autonoma de BarcelonaBarcelonaSpain Urology Department Massachusetts General HospitalHarvard Medical SchoolBostonUSA

Objective:To assess the effect of the adherence to medical treatment on urinary parameters in the 24-h metabolic study of patients with kidney ***:A retrospective,longitudinal,descriptive,and observational study was carried out by reviewing the hospital electronic medical record from 2014 to *** adherence to drug treatment was measured 6 months after its initiation,and the numerical values of the metabolic studies were *** tests were performed to compare the difference before and after ***:Ninety patients were evaluated,with 73.3% of *** 180-day overall adherence rate was 61.2% in patients treated with a single drug and 85.4% in patients treated with multiple *** is a statistically significant increase in citrate levels in patients with good adherence in comparison with non-adherent patients(p=0.031 vs.p=0.528).Conclusions:Medical treatment and dietary measures in patients with kidney stones have an initial impact at 6 months on the values of the main urinary metabolic alterations that predispose to calculi formation;the most significant is seen in those patients with adherence to medical treatment for hypocitraturia.

关键词： Kidney stones Renal stones Metabolic disorders Medical treatment Citrate Oxalate Lithiasis