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A PREDICTOR MODIFICATION TO THE EBDF METHOD FOR STIFF SYSTEMS

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Journal of Computational Mathematics 2011年第2期29卷 199-214页

作者： Elisabete Alberdi juan jose Anza Lea Artibai Ikastetxea Xemein Avenue 19 48270 Markina-Xemein (Vizcaya) Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pais Vasco Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the EBDF method using the NDFs as predictors instead of BDFs. This modification, that we call ENDF, implies the local truncation error being smaller than in the EBDF method without losing too much stability. We will also introduce two more changes, called ENBDF and EBNDF methods. In the first one, the NDF method is used as the first predictor and the BDF as the second predictor. In the EBNDF, the BDF is the first predictor and the NDF is the second one. In both modifications the local truncation error is smaller than in the EBDF. Moreover, the EBNDF method has a larger stability region than the EBDF.

关键词： Backward differentiation formula (BDF) EBDF Predictor Stability Stiff Systems.

Phenotypic plasticity in Drosophila cactophilic species the effect of competition, density, and breeding sites

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Insect Science 2017年第4期24卷 675-683页

作者： juan jose Fanara Victoria Werenkraut Departamento de Ecologia Genetica y Evolucion Instituto de Ecologia GeneUca y Evolucion de Buenos Aires (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Ciudad Universitaria Pabellon II Universidad de Buenos Aires Buenos Aires Laboratorio Ecotono Centro Regional Universitario Bariloche Universidad Nacional del ComahuelINIBIOMA-CONICET Quintral 1250 Bariloche Rio Negro Argentina

Changes in the environmental conditions experienced by naturally occurring populations are frequently accompanied by changes in adaptive traits allowing the organ- ism to cope with environmental unpredictability. Phenotypic plasticity is a major aspect of adaptation and it has been involved in population dynamics of interacting species. In this study, phenotypic plasticity （i,e., environmental sensitivity） of morphological adap- tive traits were analyzed in the cactophilic species Drosophila buzzatii and Drosophila koepferae （Diptera： Drosophilidae） considering the effect of crowding conditions （low and high density）, type of competition （intraspecific and interspecific competition） and cacti hosts （Opuntia and Columnar cacti）. All traits （wing length, wing width, thorax length, wing loading and wing aspect） showed significant variation for each environmental factor considered in both Drosophila species. The phenotypic plasticity pattern observed for each trait was different within and between these cactopbilic Drosophila species depending on the environmental factor analyzed suggesting that body size-related traits respond almost independently to environmental heterogeneity. The effects of ecological factors analyzed in this study are discussed in order to elucidate the causal factors investigated （type of com- petition, crowding conditions and alternative host） affecting the election of the breeding site and/or the range of distribution of these cactophilic species.

关键词： adaptation body size colonization Drosophila cactophilic species wingaspect wing loading

THE INTEGRATION OF STIFF SYSTEMS OF ODEs USING NDFs AND MEBDFs

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Journal of Computational Mathematics 2013年第2期31卷 175-189页

作者： Elisabete Alberdi Celaya juan jose Anza Department of Applied Mathematics EUIT de Minas y Obras P(tblicas Universidad del Pals Vasco UPV/EHU Colina de Beurko s/n 48902 Barakaldo Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pals Vasco UPV/EHU Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the MEBDF method using the NDFs as predictors instead of the BDFs. We have done it in three different ways： changing both predictors of the MEBDF, changing only the first predictor and changing only the second one. We have called the new methods MENDF, MENBDF and MEBNDF respectively. The new methods are A-stable up to order 4 and the stability properties of the new methods are better than the MEBDF method.

关键词： BDF NDF MEBDF Stiff ODEs Stability.

A neural network to predict reactor core behaviors

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Nuclear Science and Techniques 2014年第1期25卷 75-80页

作者： juan jose Ortiz-Servin David A.Pelta jose Alejro Castillo Instituto Nacional de Investigaciones Nucleares Carretera Mexico Toluca S/NLa Marquesa OcoyoacacEstado de Mexico ETS Ingenieria Informatica y Telecomunicaciones Universidad de GranadaC/Daniel Saucedo Aranda

The global fuel management problem in BWRs(Boiling Water Reactors) can be understood as a very complex optimization problem,where the variables represent design decisions and the quality assessment of each solution is done through a complex and computational expensive *** last aspect is the major impediment to perform an extensive exploration of the design space,mainly due to the time lost evaluating non promising *** this work,we show how we can train a Multi-Layer Perceptron(MLP) to predict the reactor behavior for a given *** trained MLP is able to evaluate the configurations immediately,thus allowing performing an exhaustive evaluation of the possible configurations derived from a stock of fuel lattices,fuel reload patterns and control rods *** our particular problem,the number of configurations is approximately 7.7×10^(10);the evaluation with the core simulator would need above 200 years,while only 100hours were required with our approach to discern between bad and good *** later were then evaluated by the simulator and we confirm the MLP *** good core configurations reached the energy requirements,satisfied the safety parameter constrains and they could reduce uranium enrichment costs.

关键词：神经网络预测行为质量评估堆芯沸水反应堆多层感知器 MLP 优化问题

Fecal incontinence in men:Causes and clinical and manometric features

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World Journal of Gastroenterology 2014年第24期20卷 7933-7940页

作者： Teresa Munoz-Yagüe Pablo solis-Munoz Constanza Ciriza de los Rios Francisco Muoz-Garrido Jesus Vara jose Antonio solis-Herruzo Department of Gastroenterology the University Hospital "12 de Octubre"28041-MadridSpain Institute of Liver Studies King’s College HospitalLondon SE5 9RSUnited Kingdom Pelvic Floor Unit the University Hospital "12 de Octubre"28041-MadridSpain Research Center University Hospital "12 de Octubre"Complutense University28041-MadridSpain

AIM:To determine the causes and characteristics of fecal incontinence in men and to compare these features with those presented by a group of women with the same ***:We analyzed the medical history,clinical and manometric data from 119 men with fecal incontinence studied in our unit and compared these data with those obtained from 645 women studied for the same *** to treatment was evaluated after 6 mo of ***:Fifteen percent of patients studied in our unit for fecal incontinence were *** took longer than women before asking for medical *** surgery was the most common risk factor for men related to fecal *** diarrhea was present in more than 40%of patients in both *** resting and external anal sphincter pressures were more frequent in *** significant differences existed between the sexes regarding rectal sensitivity and recto-anal inhibitory *** 17.8%of men,all presenting soiling,manometric findings did not justify fecal *** to treatment was good in both groups,as 80.4%of patients improved and fecal incontinence disappeared in 13.2%of ***:In our series,it was common that men waited longer in seeking medical help for fecal ***-rectal surgery was the major cause of this *** diarrhea was a predisposing factor in both *** differences between groups were limited to an increased frequency of hypotony of the external anal sphincter in *** incontinence was controllable in most patients.

关键词： Fecal Incontinence Gender Ano-rectal surgery Ano-rectal manometry Treatment Biofeedback

QUALITATIVE ANALYSIS OF SUSTAINABLE VERTICAL DWELLING IN NUEVO LEON, MEXICO

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Journal of Green Building 2011年第1期6卷 58-72页

作者： Pedro Morales juan P.solis Andres Trillo Salvador Garcia Civil Engineering Department.ITESM Monterrey Campus ITESM Monterrey Campus GGP

Climate change has become a big concern nowadays since the effects of fluctuation in the weather are more notable every *** Mexico construction industry generates around 33%of the countries CO_(2) emissions,and 7.64%amount for housing *** Vertical Dwelling was considered as a suitable solution to cover the housing shortage and lower the impact to the *** assessment of awareness of sustainability was carried out in the housing sector including government,developers and *** interviews were designed one for each kind of *** with the outcome of the interviews,guidelines to address sustainability in the housing sector were *** ongoing project was selected and a qualitative comparison analysis was established,making green improvements and discussing the impact of such *** an outcome we observed that sustainability is getting attention from the government and *** Housing Found has launched the Green Mortgage to promote green housing for the low income families,this program could be expanded to higher income classes and for vertical *** is not a proper regulatory framework for the condominium regimen neither for the construction of green dwellings,thus,problems arise for the condominium *** developers are implementing some green features on their projects,but not as a mean to address sustainability,but as a marketing ***,vertical dwelling represents a greener way to build by the fact that it requires less land space,vacant lands within urban areas can be recovered,thus the use of existing infrastructure and services make the projects efficient and less expensive.

关键词： sustainability vertical dwelling condominium

Selective intestinal decontamination for the prevention of early bacterial infections after liver transplantation

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World Journal of Gastroenterology 2016年第26期22卷 5950-5957页

作者： Elena Resino Rafael San-juan jose Maria Aguado Unit of Infectious Diseases 12 de Octubre University Hospital

Bacterial infection in the first month after liver transplantation is a frequent complication that poses a serious risk for liver transplant recipients as contributes substantially to increased length of hospitalization and hospital costs being a leading cause of death in this period. Most of these infections are caused by gramnegative bacilli, although gram-positive infections, especially Enterococcus sp. constitute an emerging infectious problem. This high rate of early postoperative infections after liver transplant has generated interest in exploring various prophylactic approaches to surmount this problem. One of these approaches is selective intestinal decontamination(SID). SID is a prophylactic strategy that consists of the administration of antimicrobials with limited anaerobicidal activity in order to reduce the burden of aerobic gram-negative bacteria and/or yeast in the intestinal tract and so prevent infections caused by these organisms. The majority of studies carried out to date have found SID to be effective in the reduction of gram-negative infection, but the effect on overall infection is limited due to a higher number of infection episodes by pathogenic enterococci and coagulase-negative staphylococci. However, difficulties in general extrapolation of the favorable results obtained in specific studies together with the potential risk of selection of multirresistant microorganisms has conditioned controversy about the routinely application of these strategies in liver transplant recipients.

关键词： Selective intestinal decontamination Liver transplant Infection Gram-negative bacterial infection Gram-positive bacterial infection Multirresistant

Effect of genistein supplementation of thawing medium on characteristics of frozen human spermatozoa

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Asian Journal of Andrology 2010年第3期12卷 431-441,I0012页

作者： juan Carlos Martinez-Soto juan de DiosHourcade Alfonso Gutierrez-Adan jose Lorenzo Landeras Joaquin Gadea Department of Physiology School of Veterinary Murcia University Murcia 30100 Spain IVI- MURCIA Murcia 30007 Spain Department of Animal Reproduction INIA Madrid 28040 Spain

In this study, we evaluated the effects of genistein supplementation of the thawing extender on frozen-thawed human semen parameters. We analyzed the effect of supplementation on sperm motility, capacitation （membrane lipid disorder）, reactive oxygen species （ROS） generation, chromatin condensation and DNA damage. Using this preliminary information, it maybe possible to improve the cryopreservation process and reduce the cellular damage. We have confirmed that the isoflavone genistein （10 μmol L-1） has antioxidant properties on the frozen-thawed spermatozoa. This results in a decreased ROS production that shows a slight improvement in the sperm motility, and decreases the membrane lipid disorder and DNA damage caused by cryopreservation. These results suggest an effect of genistein on sperm functionality that could be of interest for assisted reproduction treatments using frozen- thawed human spermatozoa, but further studies will be necessary to confirm our findings and to evaluate the possible clinical applications.

关键词： antioxidants cryopreservation DNA damage genistein isoflavones sperm motility

Brent *** Texas Intermediate in the US petro derivatives price formation

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Petroleum Science 2024年第1期21卷 729-739页

作者： Alejandro Almeida Antonio A.Golpe juan Manuel Martín-Alvarez jose Carlos Vides Universidad Internacional de La Rioja Department of Quantitative Methods for Economics and BusinessLa RiojaSpain University of Huelva Department of Economics and Centro de Estudios Avanzados en FisicaMatematicas y Computacion and ICEIHuelvaSpain Complutense University of Madrid Department of Applied and Structural Economics and History and ICEIMadridSpain

In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over *** the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant ***,results suggest our results show that both WTI and Brent display very similar behaviour with the refined ***,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample ***,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate ***,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined *** results possess important considerations to policymakers and the market participants and the price formation.

关键词： Crude oil prices Spatial panel model Refined products Price formation