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Failure Analysis of Austenitic Stainless Steel Implant Screws and Prospection of Chemical Composition Using Artificial Intelligence

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World Journal of Engineering and Technology 2022年第1期10卷 98-118页

作者： Alfonso Monzamodeth Román-Sedano Bernardo Campillo Fermín Castillo osvaldo flores Facultad de Química Universidad Nacional Autónoma de México Ciudad de México México Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca Morelos México

In this work, austenitic stainless steel screws employed in a locking compression plate for veterinarian use were investigated. These types of implants are widely utilized in bone fractures healing. Two surgical screws were extracted due to the observation of slight superficial red rust colorizing on one of the screw implants, visual evidence of probable screw rusting. From the same implant, another screw was extracted simultaneously without visual evidence of rusting. In order to characterize and analyze the different behavior of both screws, the chemical composition was characterized by atomic absorption and energy dispersive X-ray spectroscopy (EDS) coupled to a scanning electron microscope (SEM). Also, the screws were studied by metallography, optical microscopy (OM), Vickers microhardness tests, and SEM analysis. On the other hand, a prospection for alloy chemical composition limits of these types of implants was performed based on the Schaeffler-Delong diagram and the ASTM F-138 standard. To analyze the effect of the chemical composition, heat treatment, microstructure, pitting resistance equivalent number (PRE) and stacking fault energy (SFE), a genetic algorithm (GA) and an artificial neural network (ANN) were used. In accordance with the elemental analysis, the surgical screws do not fulfill the ranges of the chemical composition established by the ASTM F-138 standard. Furthermore, there were found differences between the microstructures of the screws. In regard to the prospection, the results of GA and ANN support the proposed chemical composition region on the Schaeffler-Delong diagram. The corrosion failure was associated with severe plastic deformation and the presence of precipitates. The proposal can minimize the cause of failures in these types of austenitic stainless steel implants.

关键词： Implant Screw Failure Analysis Genetic Algorithm Artificial Neural Network Austenitic Stainless Steel

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A Study of the Structural, Optical and Electrical Properties of SnS Thin Films Modified by Plasma

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材料科学与工程（中英文B版） 2013年第6期3卷 352-358页

作者： Aar6n Gomez Horacio Martinez Manuela Calixto-Rodriguez David Avellaneda Pedro Guillermo Reyes osvaldo flores Laboratorio de Fisica Avanzada Facultad de Ciencias Universidad Autonoma del Estado de Mexico Estado de Mexico Mexico Laboratorio de Espectroscopia Instituto de Ciencias Fisicas Universidad Nacional Aut6noma de Mdxico Cuernavaca MorelosMdxico Intituto de Energia Renovable Universidad Nacional Aut6noma de Mdxico Cuernavaca Morelos M~xico Facultad de Ingenieria Meconica y Electrica Universidad Autonoma de Nuevo Leon Mexico

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Effect of the Substitution of Sand by Rubber of Waste Tires on the Mechanical Properties of Hydraulic Concrete and Exposure to Gamma Radiation

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Journal of Minerals and Materials Characterization and Engineering 2021年第3期9卷 245-256页

作者： Jesús M. Colín de la Cruz Carmen Gabriela Guzmán Fermín Castillo Mejía Benjamin Leal Acevedo osvaldo flores Cedillo Isabel Gamboa de Buen Arturo Molina Ocampo Horacio Martínez Valencia Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de Morelos Cuernavaca México Laboratorio de Espectroscopia Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca México Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México City México Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM Cuernavaca México

For a long time and until now, rubber is the most used material for the manufacture of tires for motor vehicles. Unfortunately, once the tire meets its life cycle, the remaining rubber cannot be recycled, so the tires are discarded in collection centers and often in clandestine dumps. This represents a serious environmental problem because, in one case, these waste tires become breeding grounds for insects and wildlife that is harmful to humans. In the second case, the tires are burned, releasing highly damaging gases into the atmosphere. On the other hand, concrete is worldwide the construction material par excellence. It is basically composed of cement, gravel and sand. Mixing these three components in different proportions, their mechanical strength in compression can be increased. However, due to its fragile nature, concrete, once a crack is formed, it rapidly advances by fragmenting the material and producing its rapid collapse. In the present work, in order contribute to the care of the environment as well as to modify the fracture mode of the concrete, rubber particles obtained from waste tires were used as sand substitute in hydraulic concrete. In addition, rubber modified samples concrete were lately exposed to 70 kGy of gamma radiation in order to study the effects of this radiation on the mechanical deformation of concrete. The results showed a decrease in the mechanical properties of the concrete with rubber particles with respect to the traditional concrete itself. However, such decreases were offset by the fact that samples with rubber addition do not collapses as fast as the free rubber samples. The acquired data pave the way for research with great benefits, such as the use of recycled tires in concrete for its fracture mode modification in a beneficial way, as well as a possible decrease in the cost of concrete.

关键词： Hydraulic Concrete Scrap Tire Rubber Strength Gamma Radiation Mechanical Properties

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Dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

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Differential response of injured and healthy retinas to syngeneic and allogeneic transplantation of a clonal cell line of immortalized olfactory ensheathing glia:a double-edged sword

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Neural Regeneration Research 2025年第8期20卷 2395-2407页

作者： María Norte-Muñoz María Portela-Lomba Paloma Sobrado-Calvo Diana Simón Johnny Di Pierdomenico Alejandro Gallego-Ortega Mar Pérez JoséMCabrera-Maqueda Javier Sierra Manuel Vidal-Sanz María Teresa Moreno-flores Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la SaludMurciaSpain Experimental Sciences Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain Anatomy Histology and Neuroscience DepartmentMedicine FacultyUniversidad Autónoma de MadridMadridSpain Center of Neuroimmunology Service of NeurologyLaboratory of Advanced Imaging in Neuroimmunological DiseasesHospital Clínic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi i Sunyer(IDIBAPS)and Universitat de BarcelonaBarcelonaSpain Medicine Faculty Universidad Francisco de VitoriaPozuelo de AlarcónMadridSpain

Olfactory ensheathing glia promote axonal regeneration in the mammalian central nervous system,including retinal ganglion cell axonal growth through the injured optic ***,it is unknown whether olfactory ensheathing glia also have neuroprotective *** ensheathing glia express brain-derived neurotrophic factor,one of the best neuroprotectants for axotomized retinal ganglion ***,we aimed to investigate the neuroprotective capacity of olfactory ensheating glia after optic nerve *** ensheathing glia cells from an established rat immortalized clonal cell line,TEG3,were intravitreally injected in intact and axotomized retinas in syngeneic and allogeneic mode with or without microglial inhibition or immunosuppressive *** and gene expression analyses were *** bulb-derived primary olfactory ensheathing glia and TEG3 express major histocompatibility complex classⅡ*** and syngenically transplanted TEG3 cells survived in the vitreous for up to 21 days,forming an *** axotomized retinas,only the allogeneic TEG3 transplant rescued retinal ganglion cells at 7 days but not at 21 *** these retinas,microglial anatomical activation was higher than after optic nerve crush *** intact retinas,both transplants activated microglial cells and caused retinal ganglion cell death at 21 days,a loss that was higher after allotransplantation,triggered by pyroptosis and partially rescued by microglial inhibition or ***,neuroprotection of axotomized retinal ganglion cells did not improve with these *** different neuroprotective properties,different toxic effects,and different responses to microglial inhibitory treatments of olfactory ensheathing glia in the retina depending on the type of transplant highlight the importance of thorough preclinical studies to explore these variables.

关键词： cell therapy immune recognition major histocompatibility complex class II(MHCII) neuroprotection olfactory ensheathing glia retinal ganglion cells

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Ligand effects on the structure and vibrational properties of the thiolated Au18 cluster

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Progress in Natural Science:Materials International 2016年第5期26卷 510-515页

作者： Alfredo Tlahuice-flores CICFIM-Facultad de Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León

Most of the studies devoted to thiolated gold clusters suppose that their core and Au-S framework do not suffer from distortion independently of the protecting ligands（-SR） and it is assumed as correct to simplify the ligand as SCH3. In this work is delivered a systematic study of the structure and vibrational properties（IR and Raman）of the Au18（SR）14cluster. The pursued goal is to understand the dependency of the displayed vibrational properties of the thiolated Au18cluster with the ligands type. A set of six ligands was considered during calculations of the vibrational properties based on density functional theory（DFT） and in its dispersioncorrected approach（DFT-D）.

关键词： Gold cluster Ligand effects Structure Vibration Au18(SR)14 Density functional theory

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Curcuma longa L. extract improves the cortical neural connectivity during the aging process

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Neural Regeneration Research 2017年第6期12卷 875-880页

作者： Gonzalo flores Laboratorio de Neuropsiquiatría Instituto de Fisiología Benemérita Universidad Autónoma de Puebla

Turmeric or Curcuma is a natural product that has anti-inflammatory, antioxidant and anti-apoptotic pharmacological properties. It can be used in the control of the aging process that involves oxidative stress, inflammation, and apoptosis. Aging is a physiological process that affects higher cortical and cognitive functions with a reduction in learning and memory, limited judgment and deficits in emotional control and social behavior. Moreover, aging is a major risk factor for the appearance of several disorders such as cerebrovascular disease, diabetes mellitus, and hypertension. At the brain level, the aging process alters the synaptic intercommunication by a reduction in the dendritic arbor as well as the number of the dendritic spine in the pyramidal neurons of the prefrontal cortex, hippocampus and basolateral amygdala, consequently reducing the size of these regions. The present review discusses the synaptic changes caused by the aging process and the neuroprotective role the Curcuma has through its anti-inflammatory, antioxidant and anti-apoptotic actions.

关键词： Curcuma longa cortical curcumin hippocampus synaptic antioxidant spine connectivity cortex

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A transition from a large open pit into a novel “macroblock variant” block caving geometry at Chuquicamata mine, Codelco Chile

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 549-561页

作者： German flores Alex Catalan Newcrest Mining Ltd. Melbourne3004Australia Codelco Chile Santiago8320000Chile

With a history of more than 100 years, Chuquicamata has become one of the largest open pits in the world. Its current depth of 1100 m, length of 4500 m and width of 3000 m, resulting in haulage distances of over 11,000 m from pit bottom to the processing plant or waste dumps, with waste/ore ratio greater than 4 and much lower grades, are effectively determining its profitable limit by the end of this decade. Currently, there are over 4300 Mt of geological resources containing 0.7% of copper and 340 ppm (1 ppm = 1 g/t) of molybdenum below the final pit shell. The corresponding orebody geometry is 3000 m northsouth, 300-800 m eastwest and the drilling campaign suggested the existence of more than 900 m of mineable ore from the final pit bottom. This is in spite of the fact that the Chuquicamata orebody is still open at depth. The business case to continue with the mining of the Chuquicamata orebody is to change from the current large open pit to a novel macroblock variant block caving geometry. This requires a production rate of 140,000 t/d (50 Mt per annum), with a continuous material handling system to achieve the 7-year ramp-up to full production. The resolution of a number of known technical, operational and logistical challenges outside current industry practises which Chuquicamata will face over its projected 40-year mine life is therefore essential. These challenges include simultaneous operations of open pit and underground macroblocks and from the initial lift to the second lift, rapid ramp-up and optimum sequencing of the planned macroblocks, early dilution from the west fault and late dilution from potential slope failures, and the potential for major operational hazards. An equally important issue to be addressed is cultural given that the mining history in the northern region of Chile, which includes Chuquicamata, is predominantly open pit. This paper presents a synopsis of the main challenges that the Chuquicamata underground project will face in order t

关键词： Macroblock variant Block caving Cave propagation Early and late dilutions Intensive preconditioning Rib pillar West fault Ore buffer

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Role of N-formyl peptide receptor 2 in germinal matrix hemorrhage:an intrinsic review of a hematoma resolving pathway

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Neural Regeneration Research 2024年第2期19卷 350-354页

作者： Jerry flores Jiping Tang Department of Physiology&Pharmacology Loma Linda University School of MedicineLoma LindaCAUSA

Germinal matrix hemorrhage is one of the leading causes of morbidity,mortality,and acquired infantile hydrocephalus in preterm infants in the United States,with little progress made in its clinical *** clots have been shown to elicit secondary brain injury after germinal matrix hemorrhage,by disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage causing post-hemorrhagic hydrocephalus *** evidence suggests that rapid hematoma resolution is necessary to improve neurological outcomes after hemorrhagic *** articles have demonstrated the beneficial effects of stimulating the polarization of microglia cells into the M2 phenotype,as it has been suggested that they play an essential role in the rapid phagocytosis of the blood clot after hemorrhagic models of stroke.N-formyl peptide receptor 2(FPR2),a G-protein-coupled receptor,has been shown to be neuroprotective after ***2 activation has been associated with the upregulation of phagocytic macrophage clearance,yet its mechanism has not been fully *** literature suggests that FPR2 may play a role in the stimulation of scavenger receptor *** receptor CD36 plays a vital role in microglia phagocytic blood clot clearance after germinal matrix ***2 has been shown to phosphorylate extracellular-signal-regulated kinase 1/2(ERK1/2),which then promotes the transcription of the dual-specificity protein phosphatase 1(DUSP1)*** this review,we present an intrinsic outline of the main components involved in FPR2 stimulation and hematoma resolution after germinal matrix hemorrhage.

关键词： AnxA1 FPR2 GMH hematoma resolution hemorrhagic stroke M1 M2 microglia polarization microglia phagocytosis

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Effect of magnesium on the aluminothermic reduction rate of zinc oxide obtained from spent alkaline battery anodes for the preparation of Al–Zn–Mg alloys

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 458-465页

作者： Rocio Ochoa Alfredo flores Jesus Torres Cinvestav-Saltillo

The aluminothermic reduction of zinc oxide（ZnO） from alkaline battery anodes using molten Al may be a good option for the elaboration of secondary 7000-series alloys. This process is affected by the initial content of Mg within molten Al, which decreases the surface tension of the molten metal and conversely increases the wettability of ZnO particles. The effect of initial Mg concentration on the aluminothermic reduction rate of ZnO was analyzed at the following values： 0.90wt%, 1.20wt%, 4.00t%, 4.25wt%, and 4.40wt%. The ZnO particles were incorporated by mechanical agitation using a graphite paddle inside a bath of molten Al maintained at a constant temperature of 1123 K and at a constant agitation speed of 250 r/min, the treatment time was 240 min and the ZnO particle size was 450？500 mesh. The results show an increase in Zn concentration in the prepared alloys up to 5.43wt% for the highest initial concentration of Mg. The reaction products obtained were characterized by scanning electron microscopy and X-ray diffraction, and the efficiency of the reaction was measured on the basis of the different concentrations of Mg studied.

关键词： aluminothermic reduction alkaline batteries zinc oxide waste utilization aluminum zinc magnesium alloys

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