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Support Vector Machines for Regression: A Succinct Review of Large-Scale and Linear Programming Formulations

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International Journal of Intelligence Science 2013年第1期3卷 5-14页

作者： Pablo Rivas-Perea Juan Cota-Ruiz David Garcia Chaparro Jorge Arturo Perez Venzor Abel Quezada Carreón jose gerardo rosiles Department of Computer Science School of Engineering & Computer Science Baylor University Waco USA Department of Electrical & Computer Engineering Autonomous University of Ciudad Juárez Ciudad Juárez México rosiles Consulting El Paso USA

Support Vector-based learning methods are an important part of Computational Intelligence techniques. Recent efforts have been dealing with the problem of learning from very large datasets. This paper reviews the most commonly used formulations of support vector machines for regression (SVRs) aiming to emphasize its usability on large-scale applications. We review the general concept of support vector machines (SVMs), address the state-of-the-art on training methods SVMs, and explain the fundamental principle of SVRs. The most common learning methods for SVRs are introduced and linear programming-based SVR formulations are explained emphasizing its suitability for large-scale learning. Finally, this paper also discusses some open problems and current trends.

关键词： Support Vector Machines Support Vector Regression Linear Programming Support Vector Regression

Forecasting the Demand of Short-Term Electric Power Load with Large-Scale LP-SVR

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Smart Grid and Renewable Energy 2013年第6期4卷 449-457页

作者： Pablo Rivas-Perea Juan Cota-Ruiz David Garcia Chaparro Abel Quezada Carreón Francisco J. Enríquez Aguilera jose-gerardo rosiles Department of Computer Science School of Engineering and Computer Science Baylor University Waco USA Department of Electrical and Computer Engineering Autonomous University of Ciudad Juárez (UACJ) Ciudad Juárez México Science Applica- tions International Corporation El Paso USA.

This research studies short-term electricity load prediction with a large-scalelinear programming support vector regression (LP-SVR) model. The LP-SVR is compared with other three non-linear regression models: Collobert’s SVR, Feed-Forward Neural Networks (FFNN), and Bagged Regression Trees (BRT). The four models are trained to predict hourly day-ahead loads given temperature predictions, holiday information and historical loads. The models are trained on-hourly data from the New England Power Pool (NEPOOL) region from 2004 to 2007 and tested on out-of-sample data from 2008. Experimental results indicate that the proposed LP-SVR method gives the smallest error when compared against the other approaches. The LP-SVR shows a mean absolute percent error of 1.58% while the FFNN approach has a 1.61%. Similarly, the FFNN method shows a 330 MWh (Megawatts-hour) mean absolute error, whereas the LP-SVR approach gives a 238 MWh mean absolute error. This is a significant difference in terms of the extra power that would need to be produced if FFNN was used. The proposed LP-SVR model can be utilized for predicting power loads to a very low error, and it is comparable to FFNN and over-performs other state of the art methods such as: Bagged Regression Trees, and Large-Scale SVRs.

关键词： Power Load Prediction Linear Programming Support Vector Regression Neural Networks for Regression Bagged Regression Trees

Analysis and Validation for an Inverter-side Current Controller in LCL Grid-connected Power Systems

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 387-398页

作者： jose MSosa Panfilo R.Martinez-Rodriguez gerardo Escobar gerardo Vazquez Andres A.Valdez-Fernandez Juan F.Martinez-Garcia the Tecnologico Nacional de Mexico/ITS de Irapuato(TecNM/ITESI) IrapuatoGTO 36821Mexico the School of Sciences Autonomous University of San Luis Potosi(UASLP)San Luis PotosiSLP 78290Mexico Tecnologico de Monterrey N.L.64849Mexico

Transformerless grid-connected inverters offer greater efficiencies when transferring power from renewable energy sources to the electrical *** the grid-inverter connection is done with an LCL filter,high attenuation of switching harmonics is achieved while preserving a small-size output ***,damping must be included in the controller to assure closed-loop *** paper proposes a reference computation methodology for the inverter-side current feedback in a photovoltaic(PV)generation system connected to the grid through an LCL *** analysis of the closed-loop system stability and of the steady-state performance are presented as well as experimental validation of the closed-loop *** feedback controller includes active damping and relies on a resonant control structure which improves the ability of dealing with grid harmonic *** controller uses a reduced set of measurements,which requires the inverter-side current and grid voltage only,and assures a power factor close to unity.

关键词： LCL filter transformerless inverter grid connection inverter-side current feedback

Model based current mode control design and experimental validation for a 3φ rectifier under unbalanced grid voltage conditions

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Journal of Modern Power Systems and Clean Energy 2018年第4期6卷 777-790页

作者： P.R.MARTíNEZ-RODRIGEZ jose M.SOSA Samuel ITURRIAGA-MEDINA gerardo ESCOBAR gerardo VáZQUEZ-GUZMáN Andres A.VALDEZ-FERNáNDEZ School of Sciencies UASLP Laboratory of Electrical and Power Electronics ITESI School of Engineering Universidad Modelo

This paper addresses the control design and the experimental validation of a current mode control for a three phase voltage source rectifier. The proposed control law is able to fulfill the voltage regulation and the current tracking control objectives despite of unbalanced and distorted grid voltages. The proposed control law consists of two loops, which are referred as inner tracking loop and the outer voltage regulation loop. The inner loop is designed to provide damping to the system, which also includes and adaptive mechanism. The construction of the current reference is based on the positive component detection of thegrid voltage. Therefore, the current produced by the power rectifier is proportional to the fundamental component of the grid voltage, despite of the presence of unbalanced grid voltages. The voltage regulation loop is designed as a proportional-integral controller, which is aimed to regulate the DC output voltage to a desired level. Finally, experimental results are obtained in an experimental prototype of2 kW to evaluate the performance of the proposed controller.

关键词： Pulse-width modulation rectifier Power factor correction Positive-component Current mode control

Cucurbita ficifolia Bouché Regulates the Metabolism of Carbohydrates and Lipids in Liver by Activation of PPARα without Affectation on PPARγ in Vivo and in Vitro

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American Journal of Plant Sciences 2023年第7期14卷 763-781页

作者： Julio Cesar Almanza-Perez Vladimir Hernandez-Rosado Angeles Fortis-Barrera gerardo Blancas-Flores Edgar Alarcon-Villaseñor jose Luis Flores-Saenz Wendoline rosiles-Alanis Francisco Javier Alarcon-Aguilar Pharmacology Laboratory Department of Health Sciences Division of Biological and Health Sciences Metropolitan Autonomous University Mexico City Mexico Adyderma Medical International Institute Mexico City Mexico

Diabetes mellitus control in Mexico is practiced by using antidiabetic agents and, by empirical way using medicinal plants. Cucurbita ficifolia (C. ficifolia) has been attributed with hypoglycemic, hypotriglyceridemic, and anti-inflam- matory effects, and D-chiro-inositol (DCI), 4-hydroxybenzoic acid, and β-sitosterol were proposed as active principles. The last two compounds were suggested as activators of two transcription factors, PPARα and PPARγ, in C2C12 myocytes, which participate in β-oxidation of fatty acids and insulin sensitivity. However, the involvement of the hepatocytic and adipocytic PPARs in the effects of C. ficifolia has not yet been explored. This research aimed to determine the effects of C. ficifolia on PPARα, PPARγ, and inflammatory cytokines in streptozotocin (STZ)-induced diabetes mice, HepG2 hepatocytes and 3T3-L1 adipocytes, implicating two additional cell types associated with metabolism of carbohydrates and lipids. STZ-induced diabetes mice received C. ficifolia (200 mg/kg/day) for 30 days, measuring serum cytokines (TNF-α and IL-6). RNA was extracted from liver. Besides, HepG2 and 3T3-L1 cells were incubated (24 h) with C. ficifolia (0.078 mM DCI), using pioglitazone or fenofibrate as controls. RNA was also extracted from cells and PCR in real-time was performed to determinate PPARα and PPARγ expression. In diabetic animals, C. ficifolia decreased glycemia and body weight, decreasing the expression level of TNF-α and IL-6. In addition, C. ficifolia increased PPARα expression in liver of diabetic animals, in HepG2 and 3T3-L1 cells;PPARγ expression only significantly increased in HepG2 cells. The data suggest that the effects on the glycemia and lipids of C. ficifolia and its anti-inflammatory effects imply, besides skeletal muscle cells, hepatic and adipocytic PPARα activation, without affectation on PPARγ. PPARs regulation by C. ficifolia may improve the metabolic dysfunctions associated with metabolic disease, controlling the intake, ac

关键词： Cucurbita ficifolia Diabetes Mellitus Hypoglycemic Plants Anti-Inflammatory Plants PPARs PPARα

Chromium Differentially Affects Hydrogen Peroxide Distribution in Primary and Adventitious Roots of Arabidopsis thaliana L.

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Phyton-International Journal of Experimental Botany 2020年第1期89卷 35-43页

作者： Aaron Giovanni Munguia-Rodriguez jose Lopez-Bucio gerardo Rangel Sanchez Leon Francisco Ruiz-Herrera Yazmin Carreon-Abud Miguel Martinez-Trujillo Instituto de Investigaciones Quimico-Biológicas Universidad Michoacana de San Nicolas de HidalgoEdificio B3Ciudad UniversitariaC.P58030MoreliaMichoacanMexico Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo.Edificio RCiudad UniversitariaC.P58030 MoreliaMichoacanMexico

The post-embryonic growth of the Arabidopsis thaliana root system can be modified by different types of stress,such as sublethal concentrations of metals,which may induce the production of reactive oxygen species(ROS).In this study,the effects of different concentrations of potassium chromate(K_(2)CrO_(4))on the distribution and relative quantity of hydrogen peroxide(H_(2)O_(2))were determined in primary and adventitious roots in *** HyPer line *** line has a biosensor that specifically reports H_(2)O_(2) levels within tissues as *** root growth was inhibited at 100μM Cr(VI);in contrast,adventitious root formation was induced over the main root growth *** structures proliferated from 100-160μM Cr(VI),and much higher concentrations(180-200μM)of K_(2)CrO_(4) were required to affect their *** H_(2)O_(2) distributions were observed in the columella and lateral root cap of primary roots of plants grown in medium lacking dichromate,but following the development of toxicity symptoms,H_(2)O_(2) changed its distribution to the meristem and differentiation ***,adventitious roots had comparable H_(2)O_(2) distribution patterns in untreated plants and those exposed to Cr(VI)***,differential H_(2)O_(2) distribution correlates with the resistance of adventitious roots,but not primary roots,to dichromate and underlies cell reorganization at the apex to support growth.

关键词： Chromate hydrogen peroxide root growth meristem ion toxicity adaptation

Fibroadhesive scarring of grafted collagen scaffolds interferes with implant–host neural tissue integration and bridging in experimental spinal cord injury

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Regenerative Biomaterials 2019年第2期6卷 75-87页

作者： Haktan Altinova Sebastian Hammes Moniek Palm jose gerardo-Nava Pascal Achenbach Ronald Deumens Emmanuel Hermans Tobias Fuhrmann Arne Boecker Sabien Geraldine Antonia van Neerven Ahmet Bozkurt Joachim Weis Gary Anthony Brook Department of Neurosurgery RWTH Aachen University HospitalAachenGermany Institute of Neuropathology RWTH Aachen University HospitalAachenGermany Police Headquarters Berlin Medical CommissionBerlinGermany Institute of Neuroscience Universite Catholique de LouvainBrusselsBelgium Donnelly Centre for Cellular&Biomolecular Research University of TorontoTorontoCanada Department of Hand- Plastic and Reconstructive SurgeryBurn Centre Trauma CentreBG Trauma Centre LudwigshafenUniversity of HeidelbergLudwigshafenGermany Department of Plastic Reconstructive and Hand SurgeryBurn CentreRWTH Aachen University HospitalAachenGermany Department of Plastic AestheticHand and Burn SurgeryHelios University Hospital WuppertalUniversity Witten/HerdeckeWuppertalGermany

Severe traumatic spinal cord injury(SCI)results in a devastating and permanent loss of function,and is currently an incurable *** is generally accepted that future intervention strategies will require combinational approaches,including bioengineered scaffolds,to support axon growth across tissue scarring and cystic ***,we demonstrated that implantation of a microporous type-I collagen scaffold into an experimental model of SCI was capable of supporting functional recovery in the absence of extensive implant–host neural tissue ***,we demonstrate the reactive host cellular responses that may be detrimental to neural tissue integration after implantation of collagen scaffolds into unilateral resection injuries of the adult rat spinal *** demonstrated scattered fibroblast-like cell infiltration throughout the scaffolds as well as the presence of variable layers of densely packed cells,the fine processes of which extended along the graft–host *** reactive astroglial or regenerating axonal profiles could be seen traversing this *** encapsulation-type behaviour around bioengineered scaffolds impedes the integration of host neural tissues and reduces the intended bridging role of the *** of the cellular and molecular mechanisms underpinning this behaviour will be pivotal in the future design of collagen-based bridging scaffolds intended for regenerative medicine.

关键词： spinal cord injury CNS-scarring type-I collagen scaffold astrogliosis fibrosis encapsulation

Sensitivity,specificity and predictive values of anterior chamber tap in cases of bacterial endophthalmitis

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Eye and Vision 2017年第1期4卷 100-105页

作者： Carl Sjoholm-Gomez de Liano Vidal F.Soberon-Ventura Guillermo Salcedo-Villanueva Abril Santos-Palacios jose Luis Guerrero-Naranjo Jans Fromow-Guerra gerardo García-Aguirre Virgilio Morales-Canton Raul Velez-Montoya Retina Department Asociación para Evitar la Ceguera en MexicoHospital“Dr.Luis Sanchez Bulnes”IAPMexico CityMexico Universidad Popular Autonoma del Estado de Puebla PueblaMexico Ophthalmology Department Macula Retina ConsultantsMexico CityMexico

Background:To assess the sensitivity,specificity,positive predictive value and negative predictive value of anterior chamber tap for the diagnosis of bacterial endophthalmitis on a population with high ***:Retrospective,single centre,case series *** reviewed all medical records with clinical diagnosis of bacterial endophthalmitis in our hospital from January 1st,2000 to December 31st *** each record,we documented general demographic data,best corrected visual acuity and vitreous and aqueous tap microbiological *** cases were further divided according to the endophthalmitis aetiology to perform individual calculations of sensitivity,specificity,positive predictive value,negative predictive value,accuracy and *** used the results of the vitreous tap as the gold standard for diagnosis of bacterial *** excluded those records in which the aqueous and vitreous samples were not taken simultaneously or had an incomplete microbiological *** were assessed with chi squared statistics,with an alpha value of 0.05 for statistical ***:A total of 190 cases fulfilled the inclusion/exclusion *** culture rate from vitreous samples was 64.74%.Positive culture rate from aqueous sample was 32.11%.Bacteria isolated from aqueous samples matched those isolated from vitreous samples 78.68%of the *** overall sensitivity was 38.21%,specificity:75.51%,positive predictive value:79.66%,negative predictive value:32.74%(p=0.08).Subgroup analysis showed that anterior chamber taps in cases of post-surgical endophthalmitis had a moderate to low sensitivity(37.73%),high specificity(93%)and high positive predictive value(95%)(p<0.04).Conclusion:The sensitivity and specificity of anterior chamber tap are low and should not be used for critical therapeutic decisions in patients with suspected bacterial *** cases of post-surgical endophthalmitis,the result of an anterior chamber tap

关键词： Aqueous humour Endophthalmitis Anterior chamber tap Diagnostic test Vitreous tap Aqueous sampling Sensibility Sensitivity

IgA Nephropathy: Are We Doing Enough?

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Open Journal of Nephrology 2023年第2期13卷 116-125页

作者： jose Lucas Daza Yaroslad de la Cruz Luis Puello gerardo Gutierrez Alexander Ariza Antonio Vasquez Orlando Ariza Department of Internal Medicine Nephrology University of Buenos Aires Buenos Aires Argentina Department of Internal Medicine Hematology University of Buenos Aires Buenos Aires Argentina Department of Internal Medicine University of Buenos Aires Buenos Aires Argentina Department of Internal Medicine Cardiology University of Buenos Aires Buenos Aires Argentina

Immunoglobulin A nephropathy (IgAN) was first identified and described as a disease by Berger and Hinglais in 1968. It is the most common primary glomerulopathy worldwide [1], most prevalent in East Asians and Caucasians and rare in black individuals. There are four key elements that contribute to IgAN, which determine the severity, course, and prognosis of the disease: circulating IgA immunocomplexes that favor mesangial deposition, the efficiency of the reticuloendothelial system, mesangial cell affinity and reaction to mesangial accumulation of poorly glycosylated IgA1, and the renal tendency to glomerulosclerosis and interstitial fibrosis. Clinical manifestations among patients with IgAN include hematuria, approximately 40% to 50% of cases present with one or more episodes of hematuria, usually preceded by upper respiratory tract infections. Between 30% and 40% present with hematuria and non-nephrotic range proteinuria that may be associated with arterial hypertension and impaired renal function. The TESTING study reveal a significant decrease in outcomes such as the risk of a 40% decrease in glomerular filtration rate or the need for renal replacement therapy in the group treated with steroids. The decrease in renal function compared to the group treated in the previously mentioned STOP-IgAN trial was 4 times less than in the TESTING study. Are we doing enough? Obviously, more trials are required with the use of adequate nephroprotection measures. We present 3 patients with a diagnosis of IgA nephropathy who attend the follow-up consultation and voluntarily decide to take part in the review.

关键词： Immunoglobulin A Nephropathy (IgAN) Inhibition of the Renin-Angiotensin System (ACEI/ARA II) End-Stage Renal Disease (ESRD)