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Infectious Disease Modelling 2022年第1期7卷 199-211页

作者： david Nino-torres Andres Ríos-Gutierrez Viswanathan Arunachalam Comfort Ohajunwa Padmanabhan Seshaiyer Department of Statistics Universidad Nacional de ColombiaBogotaColombia George Mason University FairfaxVAUSA

In this paper,a stochastic epidemiological model is presented as an extension of a compartmental SEIR model with random perturbations to analyze the dynamics of the COVID-19 pandemic in the city of Bogota D.C.,*** model incorporates thespread of COVID-19 impacted by social behaviors in the population and allows for projecting the number of infected,recovered,and deceased individuals considering the mitigation measures,namely confinement and partial relaxed ***,the role of randomness using the concept of Brownian motion is emphasized to explain the behavior of the *** experiments for the stochastic model with random perturbations were performed,and the model is validated through numerical simulations for actual data from Bogota D.C.

关键词： Epidemic spread SARS-CoV-2 Compartmental modeling Stochastic perturbations Parameter estimation

Two mitochondrial haplotypes in Pterochloroides persicae （Hemiptera： Aphididae： Lachninae） associated with different feeding sites

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Insect Science 2013年第5期20卷 637-642页

作者： Mdellel Lassaad david Martinez-torres Ben Halima Kamel Monia Hight Institute of Agronomy Chott Mariem 4042 Sousse Tunisia Institut Cavanilles de Biodiversitat i Biologia Evolutiva Universitat de Valencia Apdo. Correos 22085 46071 Valencia Spain

Pterochloroides persicae （Cholodkovsky） is an aphid species belonging to the subfamily Lachninae that uses different members of Rosaceae （specially Prunus spp.） as hosts. Partial sequences from the mitochondrial cytochrome c oxidase 1 （COI） and the nuclear long-wave opsin genes were obtained for approximately 100 P. persicae aphid individuals sampled from 34 colonies collected mainly in Tunisia and other Mediterranean locations. The variability found at the mitochondrial locus revealed the presence of two maternal haplotypes in the studied area that differed in a single nucleotide. The nuclear gene analyzed, however, failed to reveal any variability in this species. The variability found at the COI locus was related to the season of aphid sampling and with the site of feeding, with haplotype I mostly detected in samples collected in spring and summer on trunks and branches and haplotype II only detected in aphids collected in autumn on roots. The observed pattern of molecular variation suggests the presence of two clonal races of P. persicae coexisting in the studied area differentially adapted to conditions prevalent in the alternative seasons and/or to different feeding sites.

关键词： aphids COI Lachninae life cycle Pterochloroides variability

Algorithms for Computing Some Invariants for Discrete Knots

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Applied Mathematics 2013年第11期4卷 1526-1530页

作者： Gabriela Hinojosa david torres Rogelio Valdez Facultad de Ciencias Universidad Autónoma del Estado de Morelos Cuernavaca México

Given a cubic knot K, there exists a projection? of the Euclidean space R3?onto a suitable plane ?such that p(K) is a knot diagram and it can be described in a discrete way as a cycle permutation. Using this fact, we develop an algorithm for computing some invariants for K: its fundamental group, the genus of its Seifert surface and its Jones polynomial.

关键词： Cubic Knots Discrete Knots Algorithms

Melatonin in the seasonal response of the aphid Acyrthosiphon pisum

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Insect Science 2020年第2期27卷 224-238页

作者： Miquel Barbera Laura Escriva Jorge Mariano Collantes-Alegre Giuseppe Meca Ezio Rosato david Martinez-torres Institut de Biologia Integrativa de Sistemes&Institut Cavanilles de Biodiversitati Biologia Evolutiva Parc Cientific Universitat de ValenciaC/Catedmtico Jose Beltran n°246980PaternaValenciaSpain Laboratory of Food Chemistry and Toxicology Faculty of PharmacyUniversitat de ValenciaBurjassotSpain Department of Genetics University of LeicesterLeicesterLE17RHUK

Aphids display life cycles largely determined by the *** the warm long-day *** aphid species reproduce by viviparous *** shortening of the photoperiod in autumn induces a switch to sexual *** and sexual females mate to produce overwintering resistant *** addition to this full life cycle(holocycle),there are anholocyelic lineages that do not respond to changes in photoperiod and reproduce continuously by *** molecular or hormonal events that trigger the scasonal response(i.c,induction of the sexual phenotypes)are still *** circadian synthesis of melatonin is known to play a key role in vertebrate photoperiodism,the involvement of the circadian clock and/or of the hor-mone melatonin in insect seasonal responses is not so well *** we show that melatonin levels in the aphid Acyrthosiphon pisum are significantly higher in holocyclice aphids reared under short days than under long days,while no differences were found between anholoeyelic aphids under the same *** also found that melatonin is localized in the aphid suboesophageal ganglion(SOG)and in the thoracic ganglionic mass(TGM).In analogy to vertcbrates,insect-type arylalkxylamine N-acetyltransferases(i-AANATs)are thought to play a key role in melatonin *** measured the expression of four I-AANAT genes identified in *** and localized two of them in situ in the insect central nervous systems(CNS).Levels of expression of these genes were compatible with the quantities of melatonin ***,like melatonin,expression of these genes was found in the SOG and the TGM.

关键词： AANAT aphid in situ hybridization melatonin photoperiodism quantification

Long-term effects of gestational diabetes mellitus on the pancreas of female mouse offspring

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World Journal of Diabetes 2024年第4期15卷 758-768页

作者： Enriqueta Muñoz-Islas Edgar david Santiago-SanMartin Eduardo Mendoza-Sánchez Héctor Fabián torres-Rodríguez Laura Yanneth Ramírez-Quintanilla Christopher Michael Peters Juan Miguel Jiménez-Andrade Unidad Académica Multidisciplinaria Reynosa-Aztlán Universidad Autónoma de TamaulipasReynosa 88740TamaulipasMexico Department of Anesthesiology Wake Forest University School of MedicineWinston SalemNC 27101United States

BACKGROUND Prolonged fetal exposure to hyperglycemia may increase the risk of developing abnormal glucose metabolism and type-2 diabetes during childhood,adolescence,and adulthood;however,the mechanisms by which gestational diabetes mellitus(GDM)predisposes offspring to metabolic disorders remain *** To quantify the nerve axons,macrophages,and vasculature in the pancreas from adult offspring born from mouse dams with *** GDM was induced by *** of streptozotocin(STZ)in ICR mouse *** 12 wk old,fasting blood glucose levels were determined in *** 15 wk old,female offspring born from dams with and without GDM were sacrificed and pancreata were processed for *** quantified the density of sensory[calcitonin gene-related peptide(CGRP)]and tyrosine hydroxylase(TH)axons,blood vessels(endomucin),and macro-phages(CD68)in the splenic pancreas using confocal *** Offspring mice born from STZ-treated dams had similar body weight and blood glucose values compared to offspring born from vehicle-treated ***,the density of CGRP+and TH+axons,endomucin+blood vessels,and CD68+macrophages in the exocrine pancreas was significantly greater in offspring from mothers with GDM vs control ***,the microvasculature in the islets was significantly greater,but not the number of macrophages within the islets of offspring born from dams with GDM compared to control *** GDM induces neuronal,vascular,and inflammatory changes in the pancreas of adult progeny,which may partially explain the higher propensity for offspring of mothers with GDM to develop metabolic diseases.

关键词： Gestational diabetes mellitus Immunohistochemistry Confocal microscopy Pancreas Offspring

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四足机器人仿生腿结构特性及其控制系统研究

机械设计与制造 2018年第A1期 150-153页

作者：黄林考谭跃刚 david Nicolas torres Barrera 赵东升武汉理工大学机电工程学院湖北武汉430000

针对四足机器人整机对单个支撑腿的要求,对机械腿结构特性和控制系统展开研究。基于对四足动物腿部生理结构分析,提出具有两个主动关节和一个被动关节的四足机器人仿生腿结构,并完成运动学特性分析。通过分析仿生四足机器人控制系统功... 详细信息

针对四足机器人整机对单个支撑腿的要求,对机械腿结构特性和控制系统展开研究。基于对四足动物腿部生理结构分析,提出具有两个主动关节和一个被动关节的四足机器人仿生腿结构,并完成运动学特性分析。通过分析仿生四足机器人控制系统功能与性能要求,提出具有开放性、模块化和结构紧凑特点的仿生四足机器人控制系统方案,基于DSP设计并实现仿生腿控制系统。实验证明仿生腿结构合理,控制系统稳定可靠且具有良好的扩展性,仿生腿系统可作为下层模块集成到仿生四足机器人系统。

关键词：四足机器人仿生腿控制系统结构特性

Forecast of the Luminescent Phenomena of Silicon Rich Oxide Films off Stoichiometry by Means of the Global Reaction Model

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Journal of Modern Physics 2015年第11期6卷 1679-1694页

作者： Néstor david Espinosa-torres José álvaro david Hernández de la Luz José Francisco Javier Flores-Gracia José Alberto Luna-López Javier Martínez-Juárez Gregorio Flores-Carrasco IC-CIDS Benemérita Universidad Autónoma de Puebla Puebla México Ex Graduate Research Trainee at Plasma Processing Laboratory Chemical Engineering Department McGill University Montreal Canada Department of Materials Science and Engineering and Chemical Engineering University Carlos III of Madrid and IAAB Madrid Spain

The Global Reaction Model describes a set of chemical reactions that can potentially occur during the process of obtaining silicon rich oxide (SRO) films, regardless of the technique used to grow such films which are an outside stoichiometry material. Particularly, chemical reactions that occur during the process of growing of SRO films by LPCVD technique are highlighted in this model. We suggest and evaluate either some types of molecules or resulting nanostructures and we predict theoretically, by applying the density functional theory, the contribution that they may have to the phenomenon of luminescence which is measured in SRO films. Also, we have calculated the opto-electronic properties of SRO films. The suggested model provides enough information required to identify the molecular structures resulting from the presence of defects in SRO films and also those corresponding to charged structures. It is also possible to detect the molecular structures which are modified due to the effect of heat treatment, and identify the presence of different oxidation states inclusive the formation of siloxanes.

关键词： Global Reactions Model Silicon Rich-Oxide Defects LPCVD Luminescence

<i>Ab Initio</i>Molecular Orbital Calculation for Optical and Electronic Properties Evaluation of Small and Medium Size Silicon Nano-Clusters Found in Silicon Rich Oxide Films

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Journal of Modern Physics 2013年第11期4卷 1-26页

作者： Néstor david Espinosa torres José Francisco Javier Flores Gracia José Alberto Luna López Juan Carlos Ramírez García Alfredo Morales Sánchez José Luis Sosa Sánchez david Hernández de la Luz Francisco Morales Morales Research Center for Advanced Materials S.C. Unit Monterrey-PIIT Apodaca México Research Center for Semiconductor Devices CIDS-ICUAP-BUAP Puebla México The Faculty of Chemical Sciences BUAP Puebla México

In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the Density Functional Theory with a functional B3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.

关键词： Nano-Crystals Silicon Clusters Silicon-Rich Oxide Luminescence Magic-Number

Chronic urticaria associated with lung adenocarcinoma—a paraneoplastic manifestation:A case report and literature review

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World Journal of Clinical Cases 2022年第21期10卷 7553-7564页

作者： Luisa Fernanda Jiménez Evis Adriana Castellón Juan david Marenco JoséMaria Mejía Camilo Andrés Rojas Franklin torres Jiménez Linda Coronell Estefanie Osorio-Llanes Evelyn Mendoza-torres Faculty of Health Sciences Universidad Libre de ColombiaSeccional BarranquillaBarranquilla 08000Colombia Faculty of Exact and Natural Sciences Universidad Libre de ColombiaSeccional BarranquillaBarranquilla 08000Colombia lty of Health Sciences Universidad Libre De ColombiaSeccional BarranquillaBarranquilla 08000AtlánticoColombia

BACKGROUND Urticaria is one of the most common causes of emergency room *** is defined as an acute inflammatory dermatosis,characterized by localized degranulation of mast cells,with consequent dermal microvascular and formation of edematous and pruritic plaques called *** affects the skin and tissues of the superficial *** it is accompanied by angioedema,which is characterized by deeper edema of the dermis and subcutaneous cellular tissue known as the urticarial-angioedema *** 15%-25%of the general population has suffered at least one type of urticaria at some point during their lifetime and hyperpermeability estimated at 7.6%-16%and has experienced acute urticaria that is usually self-limited and spontaneously resolves without requiring medical *** SUMMARY We present the case of a young male patient who was referred to our department with a clinical picture of 4 mo of pruritus associated with hives of variable sizes,irregular borders,with interlesional confluence,that were non-painful,without involvement of the palms and soles of the feet but with a tendency to progression in a generalized *** had multiple emergency room visits and poor response to antihistamines and systemic *** studies demonstrated nodules in the lower lingula segment,at the level of the greater fissure and in the anterior contour of the left anterior basal segment associated with parahiliar adenopathies in the absence of findings suggestive of infectious or autoimmune *** lobectomy was performed by thoracoscopy with resection of a lung nodule in the lingula and biopsy of the para-aortic mediastinal *** histopathological report showed the presence of poorly differentiated invasive adenocarcinoma with a solid morphological and acinar pattern with immunohistochemical description of lung tissue that expresses strong positive and diffuse reaction for thyroid transcription factor 1(TTF-1)with negati

关键词： Urticaria Lung adenocarcinoma Undifferentiated carcinoma Paraneoplastic syndromes Thyroid nuclear factor 1 Case report

Embryo and Endosperm Phytochemicals from Polyembryonic Maize Kernels and Their Relationship with Seed Germination

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Phyton-International Journal of Experimental Botany 2022年第5期91卷 929-941页

作者： J.david García-Ortíz Rebeca González-Centeno María Alejandra torres-Tapia J.A.Ascacio-Valdés JoséEspinoza-Velázquez Raúl Rodríguez-Herrera Food Research Department School of ChemistryAutonomous University of CoahuilaSaltillo25280México Plant Breeding Department Universidad Autonoma Agraria Antonio Narro(UAAAN)Saltillo25315México

Because of the growing worldwide demand for maize grain,new alternatives have been sought for breeding of this cereal,e.g.,development of polyembryonic varieties,which agronomic performance could positively impact the grain yield per unit area,and nutritional *** objectives of this study were to(1)determine the phytochemicals present in the embryo and endosperm of grain from maize families with high,low,and null polyembryony frequency,which were planted at different locations,and(2)state the relationship between these compounds and seed *** extracted phytochemicals from corn were identified by *** results showed that the genotype with the highest presence of phytochemicals was the brachytic population with high polyembryony called“BAP”,which also required less water during the germination *** number of phytochemicals in both embryo and endosperm tissues was not related to the sowing location where they came from or the type of *** number of different phytochemicals depended on the grain tissue from where they were *** chemical compounds found in the different maize tissues were related to the development of the plant,either in roots or nibs because these are mainly associated with the lignin synthesis.

关键词： Zea mays L HPLC-MS locations kernels phytochemicals