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Effects of Time Delays in a Dynamical Heart Model

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Journal of Chemistry and Chemical Engineering 2014年第3期8卷 320-323页

作者： Ricardo Paez-Hernfindez Maribel Zamora-Gomez pedro portillo-diaz Delfino Ladino-Luna Ruben Luevano-Enriquez Basic Sciences Department Metropolitan Autonomous University Campus Azcapotzalco Federal District 02200 M~xico Hospital General "Dr Gaudencio Gonzlez Garza" La Raza IMSS Federal District 02290 Mdxico

In this work, a dynamical model of the heartbeat is studied using nonlinear dynamics and considering the time delays inherent in the system. Two fixed points are associated to sustained oscillations which might be interpreted as the diastole and systole These parameters are associated with blood flow in human body called arterial pressure and are very important in the cardio-vascular diagnostic.

关键词：动力学模型心脏时滞非线性动力学时间延迟动脉血压持续振荡固定点

Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-Velázquez Alexander J. Jaramillo-Cañas Shania N. Aponte-Paris Gabriela V. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding

Benchmarking of two three-dimensional numerical models in time/space domain to predict railway-induced ground vibrations

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 245-256页

作者： Jesus Fernandez-Ruiz Luis E.Medina Rodriguez pedro Alves Costa Margarita Martinez-diaz University of La Coruna Department of Civil EngineeringCampus de ElvinaLa Coruna 15071Spain University of Porto Faculty of EngineeringRua Dr.Roberto Friass/n Porto4200-465Portugal University of La Coruna Department of Naval and Industrial EngineeringCampus de ElvinaLa Coruna 15071Spain

In the last 30 years,the scientific community has developed and proposed different models and numerical approaches for the study of vibrations induced by railway *** of them are formulated in the frequency/wave number domain and with a 2.5D ***-dimensional numerical models formulated in the time/space domain are less frequently used,mainly due to their high computational ***,these models present very attractive characteristics,such as the possibility of considering nonlinear behaviors or the modelling of excess pore pressure and non-homogeneous and non-periodic geometries in the longitudinal direction of the *** this study,two 3D numerical approaches formulated in the time/space domain are compared and experimentally *** first one consists of a finite element approach and the second one of a finite difference *** experimental validation in an actual case situated in Carregado(Portugal)shows an acceptable fitting between the numerical results and the actual measurements for both ***,there are some differences among *** study therefore includes some recommendations for their use in practical soil dynamics and geotechnical engineering.

关键词： railway vibrations time/space domain 3D numerical model finite difference method implicit finite element method

Pyridine Nucleotide Cycling and Control of Intracellular Redox State in Relation to Poly （ADP-Ribose） Polymerase Activity and Nuclear Localization of Glutathione during Exponential Growth of Arabidopsis Cells in Culture

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Molecular Plant 2009年第3期2卷 442-456页

作者： Till K. Pellny Vittoria Locato pedro diaz Vivancos Jelena Markovic Laura De Gara Federico V. Pallardo Christine H. Foyer Plant Sciences Rothamsted Research Harpenden Hefts AL5 2 JQ UK CIR UniversitA Campus Bio-Medico V. A. Del Portillo 21 00128 Roma Italy School of Agriculture Food and Rural Development Newcastle University Newcastle upon Tyne NE1 7RU UK Depto. de Fisiologia Av. Blasco Ibanez 15 46010 Valencia Spain Dipartimento di Biologia e Patologia Vegetale M E. Orabona 4 70125 Bari Italy

Pyridine nucleotides, ascorbate and glutathione are major redox metabolites in plant cells, with specific roles in cellular redox homeostasis and the regulation of the cell cycle. However, the regulation of these metabolite pools during exponential growth and their precise functions in the cell cycle remain to be characterized. The present analysis of the abundance of ascorbate, glutathione, and pyridine nucleotides during exponential growth of Arabidopsis cells in culture provides evidence for the differential regulation of each of these redox pools. Ascorbate was most abundant early in the growth cycle, but glutathione was low at this point. The cellular ascorbate to dehydroascorbate and reduced glutathione （GSH） to glutathione disulphide ratios were high and constant but the pyridine nucleotide pools were largely oxidized over the period of exponential growth and only became more reduced once growth had ceased. The glutathione pool increased in parallel with poly （ADP-ribose） polymerase （PARP） activities and with increases in the abundance of PARP1 and PARP2 mRNAs at a time of high cell cycle activity as indicated by transcriptome information. Marked changes in the intracellular partitioning of GSH between the cytoplasm and nucleus were observed. Extension of the exponential growth phase by dilution or changing the media led to increases in the glutathione and nicotinamide adenine dinucleotide, oxidized form （NAD）-plus-nicotinamide adenine dinucleotide, reduced form （NADH） pools and to higher NAD/NADH ratios but the nicotinamide adenine dinucleotide phosphate, oxidized form （NADP）-plus-nicotinamide adenine dinucleotide phosphate, reduced form （NADPH） pool sizes, and NAPD/NADPH ratios were much less affected. The ascorbate, glutathione, and pyridine nucleotide pools and PARP activity decreased before the exponential growth phase ended. We conclude that there are marked changes in intracellular redox state during the growth cycle but that redox homeostasis is maint

关键词： glutathione ascorbate Redox control cell cycle cell signaling cell redox state.

Alginate modifies the physiological impact of CeO2nanoparticles in corn seedlings cultivated in soil

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Journal of Environmental Sciences 2014年第2期26卷 382-389页

作者： Lijuan Zhao Jose R.Peralta-Videa Bo Peng Susmita Bandyopadhyay Baltazar Corral-diaz pedro Osuna-Avila Milka O.Montes Arturo A.Keller Jorge L.Gardea-Torresdey Chemistry Department The University of Texas at El Paso 500 West University Avenue University of California Center for Environmental Implications of Nanotechnology The University of Texas at El Paso 500 West University Avenue Environmental Science and Engineering PhD program The University of Texas at El Paso 500 West University Avenue Department of Biological Sciences The University of Texas at El Paso 500 West University Avenue Universidad Aut'onoma De Ciudad Ju'arez Plutarco Elias Calles # 1210 Fovissste Chamizal. Ciudad Juarez Chihuahua 32310 Mexico Chemistry Department University of Texas of the Permian Basin Odessa Bren School of Environmental Sciences and Management 3420 Bren Hall University of California

Alginates are naturally occurring components of organic matter in natural soil whose effects on nanoparticle （NP） toxicity to plants is not well understood. In the present study, corn plants were grown for one month in soil spiked with 400 mg/kg CeO2 NPs with various alginate concentrations. After one month of growth in the NPs impacted soil, plants were harvested and analyzed for Ce and mineral element concentrations. Chlorophyll concentration and heat shock protein 70, used as biomarkers for oxidative stress, were also evaluated. Results showed that, compared to CeO2 NPs treatment, alginate at 10, 50, and 100 mg/kg increased Ce concentration in roots by approximately 46%, 38%, and 29% and by 115%, 45%, and 56% in shoots, respectively. CeO 2 NPs without alginate increased Mn accumulation in roots by 34% compared to control. CeO2 NPs with low and medium alginate increased Mn by ca. 92% respect to NPs without alginate and by ca. 155% respect to control. CeO2 NPs without/with alginate significantly increased accumulation of Fe and Al in roots. In addition, alginate at 50 mg/kg increased Zn accumulation in roots by 52% compared to control. In shoots, K increased at all NP treatments but the accumulation of other elements was not affected. Alginate enlarged the impact of CeO2 NPs to corn plants by reducing chlorophyll a content and triggering overexpression of heat shock protein 70.

关键词： CeO2 NPs alginate nutrient uptake chlorophyll heat shock protein

Optimization of Resource in the Industry of Construction

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Journal of Civil Engineering and Architecture 2014年第9期8卷 1145-1150页

作者： Francisco Javier Gutierrez Garcia pedro Perez diaz pedro Sanchez Luis Department of Construction Engineering University of La Laguna Tenerife 38204 Spain

Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project and its cost. We show a model of linear entire mixed programming to solve the considered problem. The aim is to minimize the project total time, by means of the assignment of equipments of work to the different production lines of the activities to realizing. The fundamental beginning is to support the same production （rate of production in meters/day of the activity in view of the equipment of work） for tbe different equipments to achieve the maximum efficiency in each period of time. With the limited availability of resources, the work must be continuous and the period of time between operations and final must be kept. However, this paper also presents the bibliographical study on methodologies of the optimization of construction processes in response to the two objectives： time and cost. This will consider the use of recta-heuristic techniques, such as population based algorithms.

关键词： Optimization construction process heuristics mathematical programming.

The use of high resolution anterior segment optical coherence tomography for the characterization of conjunctival lymphoma, conjunctival amyloidosis and benign reactive lymphoid hyperplasia

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Eye and Vision 2019年第1期6卷 123-130页

作者： Nandini Venkateswaran Carolina Mercado Ann Q.Tran Armando Garcia pedro Francisco Monsalve diaz Sander R.Dubovy Anat Galor Carol L.Karp Bascom Palmer Eye Institute University of Miami Miller School of Medicine900 NW 17th StreetMiamiFL 33136USA Department of Ophthalmology Miami Veterans Administration Medical CenterMiamiFLUSA

Background:Conjunctival lymphoma,conjunctival amyloidosis and benign reactive lymphoid hyperplasia(BRLH)are conditions that often have a similar appearance on the ocular *** use of high resolution anterior segment optical coherence tomography(HR-OCT)enables clinicians to evaluate distinctive differences in tissue morphology and cellular patterns in various ocular surface *** this study,we characterize the morphological differences seen in conjunctival lymphoma,conjunctival amyloidosis and BRLH on HR-OCT ***:A retrospective chart review was performed of patients with biopsy proven conjunctival lymphoma,conjunctival amyloidosis and BRLH between 2012 and 2019 at the Bascom Palmer Eye *** were excluded if HR-OCT imaging was not performed on initial ***:Thirty-four total eyes of 27 patients were *** eyes had conjunctival lymphoma(16 patients),8 eyes had conjunctival amyloidosis(6 patients)and 6 eyes had BRLH(5 patients).All conditions appeared clinically as pink,red or yellow subepithelial lesions but had different features on *** lymphoma,HR-OCT images typically showed homogenous,dark subepithelial lesions with smooth borders,containing monomorphic dot-like ***-OCT images of amyloidosis typically showed heterogeneous,dark lesions with irregular borders,often containing hyperreflective linear ***-OCT images of BRLH showed variable infiltration of the subepithelial tissue,at times with homogenous lesions containing dot-like infiltrates like lymphoma and other times with more hyperreflective,subepithelial *** cytometry and gene rearrangement was needed for final differentiation between BRLH and lymphoma ***:Distinctive features on HR-OCT of conjunctival lymphoma,conjunctival amyloidosis and BRLH can help characterize these lesions beyond what is apparent with the clinical *** studies can further validate this technology’s use with m

关键词： High resolution anterior segment optical coherence tomography Ocular surface imaging Ocular surface lesions Conjunctival lymphoma Conjunctival amyloidosis Benign reactive lymphoid hyperplasia

Local Stability of Curzon-Ahlborn Cycle with Non-Linear Heat Transfer for Maximum Power Output Regime

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Journal of Modern Physics 2013年第7期4卷 22-27页

作者： Delfino Ladino-Luna pedro portillo-Díaz Ricardo T. Páez-Hernández Universidad Autónoma Metropolitana-Atzcapotzalco Física de Procesos Irreversibles Cd. México México

The study of local stability of thermal engines modeled as an endoreversible Curzon and Ahlborn cycle is shown. It is assumed a non-linear heat transfer for heat fluxes in the system (engine + environments). A semisum of two expressions of the efficiency found in the literature of finite time thermodynamics for the maximum power output regime is considered in order to make the analysis. Expression of variables for local stability and power output is found even graphic results for important parameters in the analysis of stability, and a phase plane portrait is shown.

关键词： Local Stability Thermal Engines Non-Linear Heat Transfer

On the Efficiency for Non-Endoreversible Stirling and Ericsson Cycles

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Journal of Modern Physics 2013年第12期4卷 1-7页

作者： Delfino Ladino-Luna pedro portillo-Díaz Ricardo T. Páez-Hernández Universidad Autónoma Metropolitana-Azcapotzalco Física de Procesos Irreversibles México D.F. México

An analysis of the Stirling and Ericsson cycles from the point of view of the finite time thermodynamics is made by assuming the existence of internal irreversibilities in an engine modeled by these cycles, and the ideal gas as working substance is considered. Expressions of efficiency in both regimes maximum power output and maximum ecological function are also shown. Appropriate variables are introduced so that the objective functions, namely power output, ecological function and efficiency can be functions of the reservoirs temperatures ratio and certain “measurable” parameters as a thermal conductance, the general constant of gases and the compression ratio of the cycle. Several results from the finite time thermodynamics literature are used, so that the developed methodology leads directly to appropriate expressions of the objective functions in order to simplify the optimization process.

关键词： Thermal Cycles Efficiency Power Output Ecological Function