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Effectiveness of a home-environmental intervention package and an early child development intervention on child health and development in high-altitude rural communities in the Peruvian Andes: a cluster-randomised controlled trial

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Infectious Diseases of Poverty 2022年第3期11卷 95-96页

作者： Néstor nuño Daniel Mäusezahl Jan Hattendorf hector Verastegui Mariela ortiz Stella M.Hartinger Department of Public Health and Epidemiology Swiss Tropical and Public Health InstituteKreuzstrasse 2CH-4123AllschwilSwitzerland 不详

Background: Unsafe drinking water,poor sanitation and hygiene,exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low-and middle-income *** implemented an integrated home-environmental intervention package(IHIP),comprising a kitchen sink,hygiene education and a certified improved biomass cookstove,and an early child development(ECD)programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of ***: We conducted a one-year cluster-randomised controlled trial among 317 childrenonths divided into 4 arms(IHIP+ECD,IHIP,ECD,and Control)and 40 clusters(10 clusters per arm).ECD status(socio-emotional,fine and gross motor,communication,cognitive skills,and an overall performance)measured with the Peruvian Infant Development Scale and the occurrence of self-reported child diarrhoea from caretakers were primary *** outcomes included the occurrence of acute respiratory infections and the presence of thermo-tolerant faecal bacteria in drinking *** trial was powered to compare each intervention against its control arm but it did not allow pairwise comparisons among the four *** analysis followed the intention-to-treat *** the statistical analysis,we employed generalised estimating equation models with robust standard errors and an independent correlation ***: We obtained ECD information from 101 children who received the ECD intervention(individually and combined with IHIP)and 102 *** who received the ECD intervention performed better in all the domains compared to *** found differences in the overall performance(64 vs.39%,odd ratio(oR):2.8;95%confidence interval(CI):1.6–4.9)and the cognitive domain(62 vs 46%,oR:1.9;95%CI:1.1–3.5).Data analysis of child morbidity included 154 children who received the IHIP intervention(individually and combined with ECD)and 156 ***

关键词： Child development Clinical trial Diarrhoea Improved biomass cookstoves Peru WASH

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)

Chiral Dirac Equation Derived From Quaternionic Maxwell’s Systems

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Journal of Electromagnetic Analysis and Applications 2013年第3期5卷 103-108页

作者： hector torres-Silva University School of Electrical and Electronic Engineering Arica Chile.

In the present article we propose a simple equality involving the Dirac operator and the Maxwell operators under chiral approach. This equality establishes a direct connection between solutions of the two systems and moreover, we show that it is valid when the natural relation between the frequency of the electromagnetic wave and the energy of the Dirac particle is fulfilled if the electric field E is parallel to the magnetic field H. our analysis is based on the quaternionic form of the Dirac equation and on the quaternionic form of the Maxwell equations. In both cases these reformulations are completely equivalent to the traditional form of the Dirac and Maxwell systems. This theory is a new quantum mechanics (QM) interpretation. The below research proves that the QM represents the electrodynamics of the curvilinear closed chiral waves. It is entirely according to the modern interpretation and explains the particularities and the results of the quantum field theory. Also this work may help to clarify the controversial relation between Maxwell and Dirac equations while presenting an original way to derive the Dirac equation from the chiral electrodynamics, leading, perhaps, to novel conception in interactions between matter and electromagnetic fields. This approach may give a reinterpretation of Majorana equation, neutrino mass, violation of Heinsenberg’s measurement-disturbation relationship and mass generation in systems like graphene devices.

关键词： Quaternion Dirac Equation Maxwell System

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 Modernizacion y Gobierno Electronico Ministerio Secretaria General de la Presidencia Escuela de Ingenieria Electrica Electronica Universidad de Tarapaca

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

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

Locomotor recovery after spinal cord injury:intimate dependence between axonal regeneration and re-connection

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Neural Regeneration Research 2022年第3期17卷 553-554页

作者： hector Ramiro Quintá Consejo Nacional de Investigaciones Científicas y Técnicas CONICET Laboratorio de Medicina Experimental“Dr.Jorge E.Toblli” Hospital AlemánBuenos AiresArgentina

Traumatic spinal cord injuries(SCI) are characterized by damage in the integrity of the spinal cord,which results in either temporary or permanent alterations in the locomotor,sensory and/or autonomic functions(Yezierski,2009).The traumatic event leads to impairments in voluntary control of movement below the injury by affecting the connection between the brain and the neurons localized in the spinal cord.

关键词： injuries alterations damage

Beam design for voice coil motors used for energy harvesting purpose with low frequency vibrations:A finite element analysis

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 1-17页

作者： hector A.Tinoco Department of Mechanics and Production Universidad Autonoma de Manizales(UAM)Grupo de Diseno Mecanico y Desarrollo Industrial Antigua Estaci´on del Ferrocarril Edificio Sacatin C.P.170001 Manizales-Caldas Colombia

In this study,a numerical approach is established to design a beam coupled to a Voice Coil Motor(VCM)with the aim to maximize the displacement in the inductive transducer.A finite element model is developed to simulate a VCM with different beams applying a harmonic *** VCM is extracted from a recycled hard disk drive(HDD)and a parametric modal analysis is performed to identify the material parameters of the HDD and the *** parameters are obtained comparing the real vibration modes and natural frequencies(VCM-beam)with those determined from the finite element model.A numerical-experimental case study is carried out to demonstrate that if a beam is designed for a specific low frequency vibration between 0 and 10 Hz,the displacements are maximized in the *** this purpose,real acceleration measurements taken from three individuals are used to provide the vibration signals in the numerical model.A beam is designed for one of the individuals using the natural frequency values determined from the measured *** show that the displacements are maximized in the model which coincides with the natural frequency of the chosen *** main purpose of this research is to establish a design tool for energy harvesting purposes with VCM based on low frequency vibration sources as for example gait motions.

关键词： Hard disk drive HDD energy harvesting finite element analysis Wiimote voice coil motor VCM modal analysis

Inference for a truncated positive normal distribution

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 163-176页

作者： hector J.Gomez Neveka M.olmos hector Varela Heleno Bolfarine Departamento de Ciencias Matematicas y Ffsicas Facultad de IngenierlaUniversidad Catolica de TemucoTemucoChile Departamento de Matematicas Facultad de Ciencias BasicasUniversidad de AntofagastaAntofagastaChile Departamento de Estatfstica IMEUniversidade de Sao PauloSao PauloBrazil

The main object of this paper is to study an extension of the half normal distribution defined by adding a positive truncation to it. The new model is more flexible than the half-normal distribution and contains the half normal distribution as a special case. Properties of this distribution, such as moments, hazard function and entropy are studied and parameters estimation is dealt with by using inoinents and inaxiinuin likelihood. A real data application indicates good fit performance of the new model when compared to other competitors in litera- tures.

关键词： half-normal distribution maximum likelihood truncation