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Invasive-invaded system of non-Lipschitz porous medium equations with advection

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International Journal of Biomathematics 2021年第7期14卷 299-327页

作者： Jose luis diaz Palencia Escuela Politecnica Superior Universidad Francisco de Vitoria Ctra.Pozuelo-Majadahonda Km 1 80028223Pozuelo de AlarconMadrid

This work provides analytical results towards applications in the field of invasive-invaded systems modeled with nonlinear diffusion and with *** results focus on showing regularity,existence and uniqueness of weak solutions using the condition of a nonlinear slightly positive parabolic operator and the reaction-absorption monotone *** coupling in the reaction-absorption terms,that characterizes the species interaction,impedes the formulation of a global comparison principle that is shown to exist ***,this work provides analytical solutions obtained as selfsimilar minimal and maximal profiles.A propagating diffusive front is shown to exist until the invaded specie notes the existence of the *** the desertion of the invaded st arts,the diffusive front vanishes globally and the nonlinear diffusion concentrates only on the propagating tail which exhibits finite ***,the invaded specie is shown to exhibit an exponential decay along a characteristic *** exponential decay is not trivial in the nonlinear diffusion case and confirms that the invasive continues to feed on the invaded during the desertion.

关键词： Nonlinearity reaction absorption coupled system diffusion porous media

Nonlinear parabolic predator-prey coupled system with convection

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International Journal of Biomathematics 2021年第2期14卷 83-118页

作者： Jose luis diaz Palencia Mariano Fernandez Lopez University Foundation San Pablo CEU Spain

The aim of this work is to provide a formulation of two related nonlinear diffusive convective models in the form of coupled reaction-absorption ***,the postulated models are studied with an analytical *** on,numerical evidences are considered to account for a precise *** problem(P)analyzed is of the form:ut=δΔu+c⋅∇u+v^(n),vt=ϵΔv+c⋅∇v−um,n,m∈(0,1),u_(0)(x),v_(0)(x)>0∈L^(1)_(loc)(RN)∩L^(∞)(R^(N)).(0.1)Afterwards,a related problem P_(T)is studied:ut=δΔu+c⋅∇u−v^(n)(u−d),vt=ϵΔv+c⋅∇v−u^(m)v,n,m∈(0,1),u_(0)(x),v_(0)(x)>0∈L^(1)_(loc)(R^(N))∩L^(∞)(R^(N)).(0.2)The principal aspects for analysis are related to the existence and the derivation of particular solutions to reproduce the dynamic of the interacting *** the problem PT,we make use of the TW approach to study existence of solutions and precise evolution of *** that the term predator is used to refer to an invasive behavior,while the term prey is used for the invaded species.

关键词： Nonlinearity reaction absorption coupled system diffusion,traveling waves

Modulation of immunity and inflammatory gene expression in the gut, in inflammatory diseases of the gut and in the liver by probiotics

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World Journal of Gastroenterology 2014年第42期20卷 15632-15649页

作者： Julio Plaza-diaz Carolina Gomez-Llorente luis Fontana Angel Gil Department of Biochemistry and Molecular Biology Ⅱ School of Pharmacy and Institute of Nutrition and Food Technology "Jose Mataix" Biomedical Research Center University of Granada

The potential for the positive manipulation of the gut microbiome through the introduction of beneficial microbes, as also known as probiotics, is currently an active area of investigation. The FAO/WHO define probiotics as live microorganisms that confer a health benefit to the host when administered in adequate amounts. However, dead bacteria and bacterial molecular components may also exhibit probiotic properties. The results of clinical studies have demonstrated the clinical potential of probiotics in many pathologies, such as allergic diseases, diarrhea, inflammatory bowel disease and viral infection. Several mechanisms have been proposed to explain the beneficial effects of probiotics, most of which involve gene expression regulation in specific tissues, particularly the intestine and liver. Therefore, the modulation of gene expression mediated by probiotics is an important issue that warrants further investigation. In the present paper, we performed a systematic review of the probiotic-mediated modulation of gene expression that is associated with the immune system and inflammation. Between January 1990 to February 2014, PubMed was searched for articles that were published in English using the MeSH terms “probiotics' and 'gene expression' combined with “intestines', 'liver', 'enterocytes', 'antigen-presenting cells', 'dendritic cells', 'immune system', and 'inflammation'. Two hundred and five original articles matching these criteria were initially selected, although only those articles that included specific gene expression results (77) were later considered for this review and separated into three major topics: the regulation of immunity and inflammatory gene expression in the gut, in inflammatory diseases of the gut and in the liver. Particular strains of Bifidobacteria, Lactobacilli, Escherichia coli, Propionibacterium, Bacillus and Saccharomyces influence the gene expression of mucins, Toll-like receptors, caspases, nuclear factor-κ

关键词： Gene expression Immunity Immunotolerance Inflammation Microbiota Probiotics Gut Liver

Redox Regulation of Glycogen Biosynthesis in the Cyanobacterium Synechocystis sp. PCC 6803： Analysis of the AGP and Glycogen Synthases

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Molecular Plant 2014年第1期7卷 87-100页

作者： Sandra diaz-Troya luis Lopez-Maury Ana Maria Sanchez-Riego Miguel Roldan Francisco J. Florencio Instituto de Bioquimica Vegetal y Fotosintesis Universidad de Sevilla-CSIC Americo Vespucio 49 E-41092 Sevilla Spain

Glycogen constitutes the major carbon storage source in cyanobacteria, as starch in algae and higher plants. Glycogen and starch synthesis is linked to active photosynthesis and both of them are degraded to glucose in the dark to maintain cell metabolism. Control of glycogen biosynthesis in cyanobacteria could be mediated by the regulation of the enzymes involved in this process, ADP-glucose pyrophosphorylase （AGP） and glycogen synthase, which were identified as putative thioredoxin targets. We have analyzed whether both enzymes were subjected to redox modification using purified recombinant enzymes or cell extracts in the model cyanobacterium Synechocystis sp. PCC 6803. Our results indicate that both AGP and glycogen synthases are sensitive to copper oxidation. However, only AGP exhibits a decrease in its enzymatic activity, which is recovered after reduction by DTT or reduced thioredoxin （TrxA）, suggesting a redox control of AGP. In order to elucidate the role in redox control of the cysteine residues present on the AGP sequence （C45, C185, C320, and C337）, they were replaced with serine. All AGP mutant proteins remained active when expressed in Synechocystis, although they showed different electrophoretic mobility profiles after copper oxidation, reflecting a complex pattern of cysteines interaction.

关键词： cyanobacteria glycogen Synechocystis thioredoxin redox regulation.

Grain yield losses in yellow-rusted durum wheat estimated using digital and conventional parameters under field conditions

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The Crop Journal 2015年第3期3卷 200-210页

作者： Omar Vergara-diaz Shawn C.Kefauver Abdelhalim Elazab Maria Teresa Nieto-Taladriz Jose luis Araus Unit of Plant Physiology Department of Plant BiologyFaculty of BiologyUniversity of BarcelonaDiagonal 64508028 BarcelonaSpain National Institute for Agricultural and Food Research and Technology(INIA) Ctra de la Coruna 7.528040Madrid Spain

The biotrophic fungus Puccinia striiformis f. sp. tritici is the causal agent of the yellow rust in wheat. Between the years 2010–2013 a new strain of this pathogen(Warrior/Ambition),against which the present cultivated wheat varieties have no resistance, appeared and spread rapidly. It threatens cereal production in most of Europe. The search for sources of resistance to this strain is proposed as the most efficient and safe solution to ensure high grain production. This will be helped by the development of high performance and low cost techniques for field phenotyping. In this study we analyzed vegetation indices in the Red,Green, Blue(RGB) images of crop canopies under field conditions. We evaluated their accuracy in predicting grain yield and assessing disease severity in comparison to other field measurements including the Normalized Difference Vegetation Index(NDVI), leaf chlorophyll content, stomatal conductance, and canopy temperature. We also discuss yield components and agronomic parameters in relation to grain yield and disease ***-based indices proved to be accurate predictors of grain yield and grain yield losses associated with yellow rust(R2= 0.581 and R2= 0.536, respectively), far surpassing the predictive ability of NDVI(R2= 0.118 and R2= 0.128, respectively). In comparison to potential yield, we found the presence of disease to be correlated with reductions in the number of grains per spike, grains per square meter, kernel weight and harvest index. Grain yield losses in the presence of yellow rust were also greater in later heading varieties. The combination of RGB-based indices and days to heading together explained 70.9% of the variability in grain yield and 62.7% of the yield losses.

关键词： Wheat yellow rust Field phenotyping NDVI Phenology,Puccinia striiformis RGB-based indices Triticum durum

Role of robotic-assisted pancreatic surgery:lessons learned from our initial experience

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Hepatobiliary & Pancreatic Diseases International 2017年第6期16卷 652-658页

作者： Emilio Vicente Yolanda Quijano Benedetto Ielpo Hipolito Duran Eduardo diaz Isabel Fabra luis Malave Riccardo Caruso General Surgery Department Sanchinarro University Hospital San Pablo University CEU Madrid Spain

BACKGROUND:Minimally invasive surgery has achieved worldwide acceptance in various fields, however, pancreatic surgery remains one of the most challenging abdominal procedures. In fact, the indication for robotic surgery in pancreatic disease has been controversial. The present study aimed to assess the safety and feasibility of robotic pancreatic ***:We retrospectively reviewed our experience of robotic pancreatic resection done in Sanchinarro University Hospital. Clinicopathologic characteristics, and perioperative and postoperative outcomes were recorded and ***:From October 2010 to April 2016, 50 patients underwent robotic-assisted surgery for different pancreatic pathologies. All procedures were performed using the da Vinci robotic system. Of the 50 patients, 26 were male and 24 female. The average age of all patients was 62 years. Operative time was 370 minutes. Among the procedures performed were 16 pancreaticoduodenectomies(PD), 23 distal pancreatectomies(DP), 11 tumor enucleations(TE). The mean hospital stay was 17.6 days in PD group, 9.0 days in DP group and 8.4 days in TE group. Pancreatic fistula occurred in 10 cases(20%), 2 after PD, 3 after DP, and 5 after TE. Four patients had postoperative transfusion in PD group and one in DP group. Conversion to open laparotomy occurred in four patients(8%). No serious intraoperative complications were observed. CONCLUSIONS:From our early experience, robotic pancreatic surgery is a safe and feasible procedure. Further experience and follow-up are required to confirm the role of robotic approach in pancreatic surgery.

关键词： robotic surgery pancreatic cancer minimal invasive surgery

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

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis luis Armando diaz-Torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),***,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

Visualizing the importance of oxide-metal phase transitions in the production of synthesis gas over Ni catalysts

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Journal of Energy Chemistry 2020年第11期29卷 178-186页

作者： luis Sandoval-diaz Milivoj Plodinec Danail Ivanov Stephane Poitel Adnan Hammud Hannah C.Nerl Robert Schldgl Thomas Lunkenbein Department of Inorganic Chemistry Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4-614195 BerlinGermany Electron Spectrometry and Microscopy Laboratory School of Basic SciencesEcole Polytechnique Federale de Lausanne1015 LausanneSwitzerland Max Planck Institute for Chemical Energy Conversion StiftstraJSe 34-3645470 Miihlheim a.d.RuhrGermany

Synthesis gas, composed of H2 and CO, is an important fuel which serves as feedstock for industrially relevant processes, such as methanol or ammonia synthesis. The efficiency of these reactions depends on the H2: CO ratio, which can be controlled by a careful choice of reactants and catalyst surface ***, using a combination of environmental scanning electron microscopy(ESEM) and online mass spectrometry, direct visualization of the surface chemistry of a Ni catalyst during the production of synthesis gas was achieved for the first time. The insertion of a homebuilt quartz tube reactor in the modified ESEM chamber was key to success of the setup. The nature of chemical dynamics was revealed in the form of reversible oxide-metal phase transitions and surface transformations which occurred on the performing catalyst. The oxide-metal phase transitions were found to control the production of synthesis gas in the temperature regime between 700 and 900 ℃ in an atmosphere relevant for dry reforming of methane(DRM, CO2: CH4=0.75). This was confirmed using high resolution transmission electron microscopy imaging, electron energy loss spectroscopy, thermal analysis, and C18O2 labelled *** dedicated operando approach of simultaneously studying the surface processes of a catalyst and its activity allowed to uncover how phase transitions can steer catalytic reactions.

关键词： Dry reforming of methane Partial oxidation of methane Environmental scanning electron microscopy Synthesis gas Operando