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Radicals and Kothe’s Conjecture for Skew PBW Extensions

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Communications in Mathematics and Statistics 2021年第2期9卷 119-138页

作者： armando reyes Hector Suarez Departamento de Matematicas Universidad Nacional de ColombiaSede BogotaColombia Escuela de Matemáticas y Estadística Universidad Pedagogica y Tecnológica de ColombiaSede TunjaColombia

The aim of this paper is to investigate different radicals(Wedderburn radical,lower nil radical,Levitzky radical,upper nil radical,the set of all nilpotent elements,the sum of all nil left ideals)of the noncommutative rings known as skew Poincare–Birkhoff–Witt *** characterize minimal prime ideals of these rings and prove that the Kothe’s conjecture holds for these ***,we establish the transfer of several ring-theoretical properties(reduced,symmetric,reversible,2-primal)from the coefficients ring of a skew PBW extension to the extension itself.

关键词： Armendariz rings Kothe’s conjecture Skew PBW extensions

Whole lesion histogram analysis of apparent diffusion coefficient predicts therapy response in locally advanced rectal cancer

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World Journal of Gastroenterology 2022年第23期28卷 2609-2624页

作者： Mayra Evelia Jiménez de los Santos Juan armando reyes-Pérez Victor Domínguez Osorio Yolanda Villaseñor-Navarro Liliana Moreno-Astudillo Itzel Vela-Sarmiento Isabel Sollozo-Dupont Department of Radiology National Cancer InstituteMexico 14080Mexico Department of Gastrointestinal Surgery National Cancer InstituteMexico 14080Mexico

BACKGROUND Whole-tumor apparent diffusion coefficient(ADC)histogram analysis is relevant to predicting the neoadjuvant chemoradiation therapy(nCRT)response in patients with locally advanced rectal cancer(LARC).AIM To evaluate the performance of ADC histogram-derived parameters for predicting the outcomes of patients with *** This is a single-center,retrospective study,which included 48 patients with *** patients underwent a pre-treatment magnetic resonance imaging(MRI)scan for primary tumor staging and a second restaging MRI for response *** sample was distributed as follows:18 responder patients(R)and 30 non-responders(non-R).Eight parameters derived from the whole-lesion histogram analysis(ADCmean,skewness,kurtosis,and ADC10^(th),25^(th),50^(th),75^(th),90^(th) percentiles),as well as the ADCmean from the hot spot region of interest(ROI),were calculated for each patient before and after *** all data were compared between R and non-R using the Mann-Whitney U *** measures of diagnostic accuracy were applied:the receiver operating characteristic curve and the diagnostic odds ratio(DOR).We also reported intra-and interobserver variability by calculating the intraclass correlation coefficient(ICC).RESULTS Post-nCRT kurtosis,as well as post-nCRT skewness,were significantly lower in R than in non-R(both P<0.001,respectively).We also found that,after treatment,R had a larger loss of both kurtosis and skewness than non-R(Δ%kurtosis and Δ skewness,P<0.001).Other parameters that demonstrated changes between groups were post-nCRT ADC10^(th),Δ%ADC10^(th),Δ%ADCmean,and ROIΔ%***,the best diagnostic performance was achieved byΔ%kurtosis at a threshold of 11.85%(Area under the receiver operating characteristic curve[AUC]=0.991,DOR=376),followed by post-nCRT kurtosis=0.78×10^(-3)mm^(2)/s(AUC=0.985,DOR=375.3),Δskewness=0.16(AUC=0.885,DOR=192.2)and post-nCRT skewness=1.59×10^(-3)mm^(2)/s(AUC=0.815,DOR=168.6).Finally,intraclass corr

关键词： Apparent diffusion coefficient Diffusion-weighted imaging Histogram analysis Magnetic resonance imaging Locally advanced rectal cancer

Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents

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Neural Regeneration Research 2024年第4期19卷 846-854页

作者： Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-reyes Facultad de Ciencias Naturales-Exactas y de la Educación Departamento de Biología.Universidad del Cauca Departamento de Estudios Psicológicos Universidad Icesi

Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older *** factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to *** pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental *** are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%*** contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its ***,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic ***,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in *** recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s *** epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective *** we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes.

关键词： Alzheimer’s disease epigenetics genes methylation natural products

Breaking paradigms: Long non-coding RNAs forming gene fusions with potential implications in cancer

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Genes & Diseases 2024年第3期11卷 311-323页

作者： David Sanchez-Marin Macrina Beatriz Silva-Cazares Fany Iris Porras-reyes Rebeca Garcia-Roman Alma D.Campos-Parra Posgrado en Ciencias Biologicas Facultad de MedicinaUniversidad Nacional Autonoma de MexicoCiudad de MexicoC.P.04360Mexico Unidad Academica Multidisciplinaria Region Altiplano Universidad Autonoma de San Luis Potost(UASLP)Carretera a Cedral Km 5+600Ejido San Jose de la TrojesMatehualaSan Luis PotosiC.P.78760Mexico Servicio de Anatomia Patologica Instituto Nacional de Cancerologia(INCan)Nino JesuisTlalpanCiudaddeMexicoC.P.14080Mexico Instituto de Salud Publica Universidad Veracruzana(UV)Av.Dr LuisDr.Castelazo Ayala s/nCol.Industrial AnimasXalapaVeracruzC.P.91190Mexico

Long non-coding RNAs(lncRNAs)are non-coding RNAs longer than 200 nucleotides with dynamic regulatory *** interact with a wide range of molecules such as DNA,RNA,and proteins to modulate diverse cellular functions through several mechanisms and,if deregulated,they can lead to cancer development and ***,it has been described that IncRNAs are susceptible to form gene fusions with mRNAs or other IncRNAs,breaking the paradigm of gene fusions consisting mainly of protein-coding ***,their biological significance in the tumor phenotype is still ***,their recent identification opens a new line of research to study their biological role in tumor-igenesis,and their potential as biomarkers with clinical relevance or as therapeutic *** present study aimed to review the IncRNA fusions identified so far and to know which of them have been associated with a potential *** address the current challenges to deepen their study as well as the reasons why they represent a future therapeutic window incancer.

关键词： Cancer Genefusions IncRNAs ncRNAs Therapy

Unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neuropathology and behavioral deficits in parkinsonian rats withα-synucleinopathy

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Neural Regeneration Research 2024年第9期19卷 2057-2067页

作者： Bismark Gatica-Garcia Michael J.Bannon Irma Alicia Martínez-Dávila Luis O.Soto-Rojas David reyes-Corona Lourdes Escobedo Minerva Maldonado-Berny ME Gutierrez-Castillo armando J.Espadas-Alvarez Manuel A.Fernandez-Parrilla Juan U.Mascotte-Cruz CP Rodríguez-Oviedo Irais E.Valenzuela-Arzeta Claudia Luna-Herrera Francisco E.Lopez-Salas Jaime Santoyo-Salazar Daniel Martinez-Fong Departamento de Fisiología Biofísica y NeurocienciasCentro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Department of Pharmacology Wayne State University School of MedicineDetroitMIUSA Laboratorio de Patogénesis Molecular Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Red de Medicina para la Educación y Desarrollo y la Investigación Científica de Iztacala(Red MEDICI) Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Nanoparticle Therapy Institute AguascalientesMéxico Departamento de Biociencias e Ingeniería Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y DesarrolloInstituto Politécnico NacionalCiudad de MéxicoMéxico Escuela Nacional de Medicina y Homeopatía Instituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Fisiología Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico Departamento de Biología Molecular y Biotecnología Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico Departamento de Física Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Programa de Nanociencias y Nanotecnología Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico

Parkinsonism by unilateral,intranigralβ-sitosterolβ-D-glucoside administration in rats is distinguished in that theα-synuclein insult begins unilaterally but spreads bilaterally and increases in severity over time,thus replicating several clinical features of Parkinson’s disease,a typicalα-*** Nurr1 repressesα-synuclein,we evaluated whether unilateral transfected of rNurr1-V5 transgene via neurotensin-polyplex to the substantia nigra on day 30 after unilateralβ-sitosterolβ-D-glucoside lesion could affect bilateral neuropathology and sensorimotor deficits on day 30 *** study found that rNurr1-V5 expression but not that of the green fluorescent protein(the negative control)reducedβ-sitosterolβ-D-glucoside-induced ***,a bilateral increase in tyrosine hydroxylase-positive cells and arborization occurred in the substantia nigra and increased tyrosine hydroxylase-positive ramifications in the *** addition,tyrosine hydroxylase-positive cells displayed less senescence markerβ-galactosidase and more neuron-cytoskeleton markerβIII-tubulin and brain-derived neurotrophic factor.A significant decrease in activated microglia(positive to ionized calcium-binding adaptor molecule 1)and neurotoxic astrocytes(positive to glial fibrillary acidic protein and complement component 3)and increased neurotrophic astrocytes(positive to glial fibrillary acidic protein and S100 calcium-binding protein A10)also occurred in the substantia *** effects followed the bilateral reduction inα-synuclein aggregates in the nigrostriatal system,improving sensorimotor *** results show that unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neurodegeneration(senescence and loss of neuron-cytoskeleton and tyrosine hydroxylase-positive cells),neuroinflammation(activated microglia,neurotoxic astrocytes),α-synuclein aggregation,and sensorimotor *** neurotrophic astrocytes and

关键词： A1 astrocytes A2 astrocytes gene therapy microglia motor deficits nanoparticles neurodegeneration neuroinflammation senescence α-synuclein aggregates

La modernización con caracteristicas chinas

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今日中国（西文版） 2024年第3期 40-41页

作者： MILTON reyes HERRERA 不详

Effect of the Density of Molten Metal on the Raining Phenomenon in Horizontal Centrifugal Casting

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Open Journal of Applied Sciences 2024年第7期14卷 1918-1926页

作者： Miguel A. Barron Joan reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

In this work the influence of the density of the molten metal on the emergence of the raining phenomenon in the horizontal centrifugal casting process is numerically studied. Transient 2D numerical simulations were carried out using Computational Fluid Dynamics software. Three molten metals with different density, namely aluminum, iron and lead, and three angular frequencies, namely 50, 66 and 77 rad/s were considered. It is found that the density of the molten metal significantly affects the emergence, transient or permanent, of the rain phenomenon. However, the magnitude and duration of the rain phenomenon depend on the angular frequency of the rotating mold. Likewise, since gravitational forces affect the metal according to its density, the value of the critical rotation speed of the mold is also affected.

关键词： Angular Frequency Centrifugal Force Computational Fluid Dynamics Critical Rotation Speed G Factor Horizontal Centrifugal Casting Molten Metal Density

Non-Darcy Flow in Molding Sands

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Open Journal of Applied Sciences 2024年第4期14卷 976-982页

作者： Miguel A. Barron-Meza Joan reyes-Miranda Daniel Flores-Sanchez Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

Darcy’s law is widely used to describe the flow in porous media in which there is a linear relationship between fluid velocity and pressure gradient. However, it has been found that for high numbers of Reynolds this law ceases to be valid. In this work, the Ergun equation is employed to consider the non-linearity of air velocity with the pressure gradient in casting sands. The contribution of non-linearity to the total flow in terms of a variable defined as a non-Darcy flow fraction is numerically quantified. In addition, the influence of the shape factor of the sand grains on the non-linear flow fraction is analyzed. It is found that for values of the Reynolds number less or equal than 1, the contribution of non-linearity for spherical particles is around 1.15%.

关键词： Darcy’s Law Molding Sands Non-Darcy Flow Reynolds Number Shape Factor

Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula

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Journal of Environmental Protection 2024年第7期15卷 796-826页

作者： Juan A. Vazquez-Morales Eliane R. Rodrigues Hortensia J. reyes-Cervantes Facultad de Ciencias Fsico-Matemticas Benemrita Universidad Autnoma de Puebla Puebla Mexico Instituto de Matemticas Universidad Nacional Autnoma de Mxico Mexico City Mexico

In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metropolitan area. In order to obtain the joint distributions a copula will be considered. Since we are analyzing the monthly maxima, the extreme value distributions of Weibull and Fréchet are taken into account. Using these two distributions as marginal distributions in the copula a Bayesian inference was made in order to estimate the parameters of both distributions and also the association parameters appearing in the copula model. The pollutants taken into account are ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, and particulate matter with diameters smaller than 10 and 2.5 microns obtained from the Mexico City monitoring network. The estimation was performed by taking samples of the parameters generated through a Markov chain Monte Carlo algorithm implemented using the software OpenBugs. Once the algorithm is implemented it is applied to the pairs of pollutants where one of the coordinates of the pair is ozone and the other varies on the set of the remaining pollutants. Depending on the pollutant and the region where they were collected, different results were obtained. Hence, in some cases we have that the best model is that where we have a Fréchet distribution as the marginal distribution for the measurements of both pollutants and in others the most suitable model is the one assuming a Fréchet for ozone and a Weibull for the other pollutant. Results show that, in the present case, the estimated association parameter is a good representation to the correlation parameters between the pair of pollutants analyzed. Additionally, it is a straightforward task to obtain these correlation parameters from the corresponding association parameters.

关键词： Copula Extreme Value Distribution Bayesian Inference Air Pollution Mexico City