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American Journal of Analytical Chemistry 2012年第11期3卷 755-760页

作者： María Carmen Yebra-Biurrun jesús manuel castro-romero Nieves Carro-Marino Department of Analytical Chemistry Nutrition and BromatologyFaculty of ChemistryUniversity of Santiago de CompostelaSantiago de CompostelaSpain Department of Analytical Chemistry Escuela Universitaria PolitécnicaUniversity of A CorunaA CorunaSpain Technological Institute for the Monitoring of the Maritime Environment of Galicia(INTECMAR) Vilagarcía de ArousaSpain

A flow injection preconcentration system for the flame atomic absorption spectrometric determination of hexavalent chromium has been developed. The method employs on-line preconcentration of Cr(VI) on a minicolumn packed with Cr(VI)-imprinted poly(4-vinyl pyridineco-2-hydroxyethyl methacrylate) placed into a flow injection system. Hexava-lent chromium was eluted with a small volume of diluted hydrochloric acid into the nebulizer-burner system of a flame atomic absorption spectrometer. An enrichment factor of 550 and a 3σ detection limit of 0.04 μg·L-1 along a sampling frequency of 4 h-1 at a sample flow rate of 3.5 mL·min-1. The relative standard deviation is 2.9% for 1 μg·L-1 Cr(VI) (n = 11). The flow injection system proposed has the advantage of being simpler because the use of expensive and sophisticated instruments is avoided. Ease of use, continuous process and selectivity make this method suitable for Cr(VI) determination in different environmental samples such as sea and river waters, soils and sediments.

关键词： Hexavalent Chromium Flame Atomic Absorption spectrometry Preconcentration Flow Injection Environmental samples

Effect of magnetic field orientation on fluidized beds of magnetic particles:Theory and experiment

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Particuology 2014年第1期12卷 54-63页

作者： Miguel ángel sánchez Quintanilla manuel jesús Espin José manuel Valverde Department of Electronics and Electromagnetism University of Seville Department of Applied PhysicsⅡ University of Seville

Geldart-A fluidized beds of fine particles experience a jamming transition between a fluid-like state and a solid-like state at a certain superficial gas velocity, that depends on the relative strength of interparticle attractive forces with respect to particle weight, lnterparticle forces provide the bed with a certain tensile strength in the jammed state. In the work presented here we analyze the behavior of a fluidized bed of magnetic particles subjected to an externally applied magnetic field, which contributes to enhance interparticle forces. The importance of the magnetic contribution to interparticle forces is measured by the changes in the tensile strength and the superficial gas velocity at the jamming transition. The link of the field orientation with the microstructure of the bed is discussed,

关键词： Magneto-fluidization Jamming transition Fluidization Fine powders Cohesion Magnetization

Hepatobiliary manifestations in inflammatory bowel disease: The gut,the drugs and the liver

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World Journal of Gastroenterology 2013年第42期19卷 7327-7340页

作者： María Rojas-Feria manuel castro Emilio suárez Javier Ampuero manuel romero-Gómez Unit for Medical and surgical Management of Digestive Diseases and CIBERehd Valme University HospitalUniversity of SevilleE-41014 SevillaSpain

Abnormal liver biochemical tests are present in up to30%of patients with inflammatory bowel disease(IBD),and therefore become a diagnostic *** and biliary tract diseases are common extraintestinal manifestations for both Crohn’s disease and ulcerative colitis(UC),and typically do not correlate with intestinal *** sclerosing cholangitis(PsC)is the most common hepatobiliary manifestation of IBD,and is more prevalent in *** 5%of patients with UC develop PsC,with the prevalence reaching up to 90%.Cholangiocarcinoma and colon cancer risks are increased in these *** common disorders include autoimmune hepatitis/PsC overlap syndrome,IgG4-associated cholangiopathy,primary biliary cirrhosis,hepatic amyloidosis,granulomatous hepatitis,cholelithiasis,portal vein thrombosis,liver abscess,and non-alcoholic fatty liver *** B reactivation during immunosuppressive therapy is a major concern,with screening and vaccination being recommended in serologically negative cases for patients with *** prophylaxis with entecavir or tenofovir for 6to 12 mo after the end of immunosuppressive therapy is mandatory in patients showing as hepatitis B surface antigen(HBsAg)positive,independently from viral *** negative and anti-HBc positive patients,with or without anti-HBs,should be closely monitored,measuring alanine aminotransferase and hepatitis B virus DNA within 12 mo after the end of therapy,and should be treated if the viral load *** the other hand,immunosuppressive therapy does not seem to promote reactivation of hepatitis C,and hepatitis C antiviral treatment does not influence IBD natural history *** of the drugs used for IBD treatment may induce hepatotoxicity,although the incidence of serious adverse events is *** in liver biochemical tests associated with aminosalicylates are uncommon and are usually not clinically *** hepatotoxicity has been describ

关键词： Inflammatory bowel disease Hepatobiliary disorders Extraintestinal manifestations Primary sclerosing cholangitis Drug-induced liver injury Hepatotoxicity Hepatitis B Hepatitis C

Insulin resistance and hepatitis C

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World Journal of Gastroenterology 2006年第44期12卷 7075-7080页

作者： manuel romero-Gómez Unit for the Clinical Management of Digestive Diseases. Hospital Universitario de Valme. Ctra de Cádiz s/n 41014 Sevilla Spain

Insulin resistance is the major feature of the metabolic syndrome and depends on insulin secretion and insulin sensitivity. In chronic hepatitis C, insulin resistance and type 2 diabetes mellitus are more often seen than in healthy controls or chronic hepatitis B patients. Hepatitis C virus （HCV） infection promotes insulin resistance, mainly by increased TNF production together with enhancement of suppressor of cytokine （sOC-3）; both events block PI3K and Akt phosphorylation. Two types of insulin resistance could be found in chronic hepatitis C patients＇. ＂viral＂ and ＂metabolic＂ insulin resistance. Insulin resistance in chronic hepatitis C is relevant because it promotes steatosis and fibrosis. The mechanisms by which insulin resistance promotes fibrosis progression include：（1） steatosis, （2） hyperleptinemia, （3） increased TNF production, （4） impaired expression of PPARy receptors. Lastly, insulin resistance has been found as a common denominator in patients difficult-to-treat like cirrhotics, overweight, HIV coinfected and Afro-American. Insulin resistance together with fibrosis and genotype has been found to be independently associated with impaired response rate to peginterferon plus ribavirin. Indeed, in genotype 1, the sustained response rate was twice （60%） in patients with HOMA ≤ 2 than patients with HOMA 〉 2. In experiments carried out on Huh-7 cells transfected by full length HCVRNA, interferon alpha blocks HCV replication. However, when insulin （at doses of 128 μU/mL, similar that seen in the hyperinsulinemic state） was added to interferon, the ability to block HCV replication disappeared, and the PKR synthesis was abolished. In summary, hepatitis C promotes insulin resistance and insulin resistance induces interferon resistance, steatosis and fibrosis progression.

关键词： Diabetes mellitus Homeostasis model of assessment Fibrosis steatosis sustained response Peginterferon Ribavirin

Virtual Conductance Based Cascade Voltage Controller for VsCs in Islanded Operation Mode

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Journal of Modern Power systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco jesús Matas-Díaz manuel Barragán-Villarejo Juan Carlos Olives-Camps Juan manuel Mauricio JoséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Clinical characteristics and type of antithrombotic treatment in a spanish cohort of elderly patients with atrial fibrillation according to dependency, frailty and cognitive impairment

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Journal of Geriatric Cardiology 2018年第4期15卷 268-274页

作者： Jose Maria Mostaza manuel jesús romero Jiménez Fernando José Ruiz Laiglesia José Antonio Díaz Peromingo manuel Beltrán Robles Ernesto Guevara sierra Ana santander Bilbao Carmen suárez Hospital Carlos III Madrid Spain Hospital Infanta Elena Huelva Spain Hospital Clínico Universitario Lozano Blesa Zaragoza Spain Complejo Hospitalario Universitario de santiago Santiago de Compostela Spain Hospital Virgen del Camino Sanlucar-Cádiz Spain Centro socio-sanitario Vallparadís Terrassa Spain Hospital de Basurto Bilbao Spain Hospital Universitario de La Princesa Madrid Spain

Background Available data regarding clinical profile and management of elderly patients with atrial fibrillation （AF） according to dependency, fragility and cognitive impairment are scarce. The objective of the study was to analyze the biodemographic data, clinical profile and antithrombotic treatment according to dependency, fragility and cognitive impairment in elderly AF patients. Methods Cross- sectional and multi-center study performed in consecutive AF patients ≥ 75 years treated with oral anticoagulants ≥ 3 months attended in Internal Medicine Departments in spain. Results A total of 837 patients （83.0 ± 5.0 years; CHA2Ds2-VAsc： 5.0 ± 1.4; HAs-BLED： 2.1 ± 0.9） were included. 44.4% of patients had some degree of dependency, 43.3% were fragile, and 32.3% had cognitive impairment. Patients with any of these conditions were older, had a worse clinical profile, with more comorbidities and higher risks of thromboembolic and bleeding events. All these conditions were independently associated among them. Overall, 70.8% of patients were taking vitamin K antagonists, the remaining 29.2% direct oral anticoagulants and 9.7% oral antiplatelets. This distribution was independent of the presence of dependency or fragility, but there was a trend to a higher prescription of vitamin K antagonists in those patients with cognitive impairment （75.2% vs. 68.8%; P = 0.05）. Conclusions Approximately 32%-44% of elderly anticoagulated AF patients attended have some degree of dependency, fragility and/or cognitive impairment. Patients with any of these conditions are older and have a worse clinical profile. Ap？proximately 71% of patients are taking vitamin K antagonists, regardless dependency or frailty, but with a trend to higher prescription in patients with cognitive impairment.

关键词： Atrial fibrillation Cognitive impairment Dependency Fragility Oral anticoagulants

steatosis and insulin resistance in hepatitis C: A way out for the virus?

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World Journal of Gastroenterology 2009年第40期15卷 5014-5019页

作者： José A Del Campo manuel romero-Gómez Unit for The Clinical Management of Digestive Diseases and CIBERehd Hospital Universitario de Valme

The hepatitis C virus (HCV) induces lipid accumulation in vitro and in vivo. The pathogenesis of steatosis is due to both viral and host factors. Viral steatosis is mostly reported in patients with genotype 3a, whereas meta-bolic steatosis is often associated with genotype 1 and metabolic syndrome. several molecular mechanisms responsible for steatosis have been associated with the HCV core protein, which is able to induce gene expres-sion and activity of sterol regulatory element binding protein 1 (sREBP1) and peroxisome proliferator-activat-ed receptor γ (PPARγ), increasing the transcription of genes involved in hepatic fatty acid synthesis. steatosis has been also implicated in viral replication. In infected cells, HCV core protein is targeted to lipid droplets which serve as intracellular storage organelles. These studies have shown that lipid droplets are essential for virus assembly. Thus, HCV promotes steatosis as an eff icient mechanism for stable viral replication. Chronic HCV in-fection can also induce insulin resistance. In patients with HCV, insulin resistance is more strongly associated with viral load than visceral obesity. HCV seems to lead to insulin resistance through interference of intracellular insulin signalling by HCV proteins, mainly, the serine phosphorylation of insulin receptor-1 (IRs-1) and im-pairment of the downstream Akt signalling pathway. The HCV core protein interferes with in vitro insulin signal-ling by genotype-specif ic mechanisms, where the role of suppressor of cytokine signal 7 (sOCs-7) in genotype 3aand mammalian target of rapamycin (mTOR) in geno-type 1 in IRs-1 downregulation play key roles. steatosis and insulin resistance have been associated with f ibrosis progression and a reduced rate of sustained response to peginterferon plus ribavirin.

关键词： steatosis Insulin resistance Hepatitis Cvirus

Modulation of faecal metagenome in Crohn's disease:Role of microRNAs as biomarkers

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World Journal of Gastroenterology 2018年第46期24卷 5223-5233页

作者： María Rojas-Feria Teresa romero-García Jose Angel Fernández Caballero-Rico Helena Pastor Ramírez Marta Avilés-Recio manuel castro-Fernandez Natalia Chueca Porcuna manuel romero-Gomez Federico García Lourdes Grande JoséA Del Campo Department of Digestive Diseases Valme University HospitalUGC Digestive Disease and CIBERehdServicio Andaluz de SaludSeville E-41014Spain Complejo Hospitalario Universitario de Granada MicrobiologyGranada E-18016Spain Institute of Biomedicine of seville Digestive DiseasesHospital Universitario Virgen del Rocío and CIBERehdSeville E-41013Spain Facultad de ciencias de la salud.Universidad Europea Miguel de Cervantes Madrid E-28280Spain

BACKGROUND The gut microbiota plays a key role in the maintenance of intestinal homeostasis and the development and activation of the host immune system. It has been shown that commensal bacterial species can regulate the expression of host genes. 16 s rRNA gene sequencing has shown that the microbiota in inflammatory bowel disease(IBD) is abnormal and characterized by reduced diversity. Micro RNAs(miRNAs) have been explored as biomarkers and therapeutic targets, since they are able to regulate specific genes associated with Crohn's disease(CD). In this work, we aim to investigate the composition of gut microbiota of active treatment-na?ve adult CD patients, with miRNA profile from gut *** To investigate the composition of gut microbiota of active treatment-na?ve adult CD patients, with miRNA profile from gut *** Patients attending the outpatient clinics at Valme University Hospital without relevant co-morbidities were matched according to age and gender. Faecal samples of newonset CD patients, free of treatment, and healthy controls were collected. Faecal samples were homogenized, and DNA was amplified by PCR using primers directed to the 16 s bacterial rRNA gene. Pyrosequencing was performed using Gs-Junior platform. For sequence analysis, MGRAsT server with the database Ribosomal Project was used. MiRNA profile and their relative abundance were analyzed by quantitative *** Microbial community was characterized using 16 s rRNA gene sequencing in 29 samples(n = 13 CD patients, and n = 16 healthy controls). The mean shannon diversity was higher in the healthy control population compared to CD group(5.5 vs 3.7). A reduction in Firmicutes and an increase in Bacteroidetes were found. Clostridia class was also significantly reduced in CD. Principal components analysis showed a grouping pattern, identified in most of the subjects in both groups, showing a marked difference between control and CD groups. A functional metabolic study showe

关键词： Crohn’s disease Dysbiosis microRNAs Firmicutes Bacteroidetes

Influence of oxidation of automatic transmission fluids (ATFs) and sliding distance on friction coefficients of a wet clutch in the running-in stage

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Friction 2021年第2期9卷 401-414页

作者： Leonardo Israel FARFAN-CABRERA Ezequiel Alberto GALLARDO-HERNÁNDEZ manuel VITE-TORREs jesús Gilberto GODÍNEZ-sALCEDO Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501Monterrey 64849México Instituto Politécnico Nacional SEPI-Escuela Superior de Ingeniería Mecánica y EléctricaUnidad ZacatencoGrupo de TribologíaCol.LindavistaCiudad de México 07738México Instituto Politécnico Nacional ESIQIEIPNCol.LindavistaCiudad de México 07738México

In this paper,the influence of oxidation of automatic transmission fluids(ATFs)and sliding distance on the friction coefficients of a wet clutch in approached running-in conditions was *** ATFs were oxidized by a laboratory process approaching oxidation occurred in actual *** was evaluated by means of increase in carbonyl compounds and depletion of zinc dialkyldithiophosphates(ZDDPs)***,the changes in kinematic viscosity and viscosity index were ***-ondisk tests were conducted to replicate the actual sliding contact in a wet *** pin specimens were cut from friction material composite plates and the disks were actual steel separators both from an automotive wet *** coefficient, μ,was measured at progressive sliding velocity,ν,to obtain μ–νcurves at 26 and 100°*** μ–νtests were consecutively run using the same pair of specimens and *** cumulative sliding distance for each μ–νtest generated surface flattening using the *** friction coefficients of the wet clutch increased due to the ATFs oxidation meanwhile the dm/dv values decreased in most *** suggests that ATF oxidation can enhance torque capacity of the wet clutch,but it could reduce anti-shudder *** sliding distance improved the slopes in the μ–νresults using fresh ATFs meanwhile it generated a slope decrease by using aged ATFs.

关键词： wet clutch friction oil oxidation automatic transmission fluid(ATF)

software Vulnerabilities Overview:A Descriptive study

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Tsinghua science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín sánchez Juan manuel Carrillo de Gea José Luis Fernández-Alemán jesús Garcerán Ambrosio Toval the Department of Informatics and systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases