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Wear protection assessment of ultralow viscosity lubricants in high-power-density engines:A novel wear prediction algorithm

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Friction 2024年第8期12卷 1785-1800页

作者： Javier BlANCO-RODRÍGUEZ Jacobo PORTEIRO joséA.lÓpez-CAMPOS MartíCORTADA-GARCÍA Silvia fernÁndez-CASTEJÓN CINTECX Universidade de VigoLagoas-Marcosende s/nVigo 36310Spain Repsol SA MadridSpain

Durability and reliability have been studied for decades through intensive trial-error ***,there are numerous fields of application where the costs associated with this approach are not *** lubricated machines with severe dynamic loads,such as high-power-density engines,simulation tools offer clear advantages over intensive *** and multiple scenarios can be cost-effectively simulated to assess different lubricants and engine *** work presented here details the study of wear based on a validated elastohydrodynamic(EHD)simulation model of the connecting rod journal *** model accounts for elastic deformation through a connecting rod finite element model(FEM).In addition,multiple lubricant rheological and tribological dependences,determined by specific experimental tests,are applied in the model through their interaction with the simulation ***,a novel wear algorithm is proposed to predict wear depth over time evolution along a proposed wear cycle based on the typical working ranges of high-performance engines.A final assessment is presented to compare 4 different ultralow-viscosity lubricants in their protective performance under severe *** results show the evolution of the wear load and wear depth over the wear *** evaluation is key to describing a lubricant selection procedure for high-power-density engines.

关键词： wear modelling finite element modelling mixed lubrication elastohydrodynamic(EHD) internal combustion engines bearings

Neuroprotective effects of meloxicam on transient brain ischemia in rats:the two faces of anti-inflammatory treatments

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Neural Regeneration Research 2023年第9期18卷 1961-1967页

作者： Irene fernández Ugidos Paloma González-Rodríguez María Santos-Galdiano Enrique Font-Belmonte Berta Anuncibay-Soto Diego Pérez-Rodríguez joséManuel Gonzalo-Orden Arsenio fernández-lópez Área de Biología Celular Instituto de BiomedicinaCampus de Vegazana s/nUniversidad de LeónLeónSpain Neural Therapies Sl.Edif.Institutos de Investigación.Planta baja.local B43.Campus de Vegazana s/n.león.Spain Department of Medicina Cirugía y Anatomía VeterinariaUniversity of LeónLeónSpain Department of Pharmacology Tulane University School of MedicineNew OrleansLAUSA Department of Neurology David Geffen School of Medicine at University of California(UCLA)Los AngelesCAUSA Department of life Sciences Imperial College London(ICL)LondonUK Department of Clinical and Movement Neurosciences UCL Queen Square Institute of NeurologyLondonUK

The inflammato ry response plays an important role in neuroprotection and regeneration after ischemic *** use of non-ste roidal anti-inflammatory drugs has been a matter of debate as to whether they have beneficial or detrimental *** this context,the effects of the anti-inflammatory agent meloxicam have been scarcely documented after stro ke,but its ability to inhibit both cyclooxygenase isoforms(1 and 2) could be a promising strategy to modulate postischemic *** study analyzed the effect of meloxicam in a transient focal cerebral ischemia model in rats,measuring its neuroprotective effect after 48 hours and 7 days of reperfusion and the effects of the treatment on the glial scar and regenerative events such as the generation of new progenitors in the subventricular zone and axonal sprouting at the edge of the damaged *** show that meloxicam’s neuroprotective effects remained after 7 days of reperfusion even if its administration was restricted to the two first days after ***,meloxicam treatment modulated glial scar reactivity,which matched with an increase in axonal ***,this treatment decreased the formation of neuronal progenitor *** study discusses the dual role of anti-inflammatory treatments after stro ke and encourages the careful analysis of both the neuroprotective and the regenerative effects in preclinical studies.

关键词： anti-inflammatories astrocyte axonal sprouting cylinder test doublecortin focal brain ischemia glial scar inflammation neuroprotection new neuron generation transient stroke

Can DNA fragmentation of neat or swim-up spermatozoa be used to predict pregnancy following ICSI of fertile oocyte donors？

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Asian Journal of Andrology 2013年第6期15卷 812-818,I0010页

作者： Jaime Gosálvez Pedro Caballero Carmen lópez-fernández leonor Ortega josé Andrés Guijarro josé luís fernAndez Stephen D Johnston Rocio Nufiez-Calonge Faculty of Biology Autonomous University of Madrid Cantoblanco Madrid 28049 Spain CIfnica Tambre Madrid 28002 Spain GINIBIC-Complejo Hospitalario Universitario A CoruRa A Corufna15006 Spain School of Agriculture and Food Science The University of Queensland Gatton 4343 Australia

This study compared the potential of assessing sperm DNA fragmentation （SDF） from neat semen and the subsequent swim-up （SU） procedure to predict pregnancy when conducting ICSI of fertile donor oocytes. Infertile females （n=81） were transferred embryos resulting from intracytoplasmic sperm injection （ICSI） of their partner＇s spermatozoa and proven donor oocytes. This model normalized the impact of female factor in putative sperm DNA repair. Semen was blindly assessed for SDF using Halosperm immediately following ejaculation （NS） and after swim-up at the time of ICSI fertilisation. There was a decrease in SDF values of the ejaculated semen sample following the swim-up protocol （P=0.000）. Interestingly, pregnancy could be equally predicted from SDF values derived from either neat or swim-up semen samples. Receiver operator curves and the derived Youden＇s indices determined SDF cutoff values for NS and SU of 24.8% and 17.5%, respectively. Prediction of pregnancy from NS SDF had a sensitivity of 75% and a specificity of 69%, whereas for SU SDF was 78% and 73%, respectively. While increased levels of SDF negatively impact reproductive outcome, we have shown that a reduction in SDF following sperm selection using ICSI with proven donor oocytes is not mandatory for achieving pregnancy. This suggests that a certain level of DNA damage that is not detectable using current technologies could be impacting on the relative success of assisted reproductive technology （ART） procedures. Consequently, we propose a modification of the so called ＇iceberg model＇ as a possible rationale for understanding the role of SDF in reproductive outcome.

关键词： assisted reproductive technology egg donation male factor sperm DNA fragmentation

Acute-on-chronic liver failure:Pathogenesis,prognostic factors and management

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World Journal of Gastroenterology 2015年第42期21卷 12125-12140页

作者： Sara Blasco-Algora josé Masegosa-Ataz María luisa Gutiérrez-García Sonia Alonso-lópez Conrado M fernández-Rodríguez Service of Gastroenterology Hospital Universitario Fundación

Acute-on-chronic liver failure(AClF) is increasingly recognized as a complex syndrome that is reversiblein many cases. It is characterized by an acute deterioration of liver function in the background of a pre-existing chronic liver disease often associated with a high short-term mortality rate. Organ failure(OF) is always associated, and plays a key role in determining the course, and the outcome of the disease. The definition of AClF remains controversial due to its overall ambiguity, with several disparate criteria among various associations dedicated to the study of liver diseases. Although the precise pathogenesis needs to be clarified, it appears that an altered host response to injury might be a contributing factor caused by immune dysfunction, ultimately leading to a pro-inflammatory status, and eventually to OF. The PIRO concept(Predisposition, Insult, Response and Organ Failure) has been proposed to better approach the underlying mechanisms. It is accepted that AClF is a different and specific form of liver failure, where a precipitating event is always involved, even though it cannot always be ascertained. According to several studies, infections and active alcoholism often trigger AClF. Viral hepatitis, gastrointestinal haemorrhage, or drug induced liver injury, which can also provoke the syndrome. This review mainly focuses on the physiopathology and prognostic aspects. We believe these features are essential to further understanding and providing the rationale for improveddisease management strategies.

关键词： Acute on-chronic liver failure Immune dysfunction

Estimation of visceral fat is useful for the diagnosis of significant fibrosis in patients with non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2020年第42期26卷 6658-6668页

作者： Marta Hernández-Conde Elba llop Carlos fernández Carrillo Beatriz Tormo Javier Abad luis Rodriguez Christie Perelló Marta lópez Gomez joséluis Martínez-Porras Natalia fernández Puga Maria Trapero-Marugan Enrique Fraga Carlos Ferre Aracil joséluis Calleja Panero Gastroenterology and Hepatology Department IDIPHISAHospital Universitario Puerta de Hierro-MajadahondaMadrid 28222Spain Centro de Investigación Biomédica en Red en elÁrea temática de Enfermedades Hepáticas Instituto de Salud Carlos IIIMadrid 28029Spain

BACKGROUND Obesity is a risk factor for non-alcoholic fatty liver disease(NAFlD),although obese patients with NAFlD do not always develop significant *** distribution of body fat could predict the risk of NAFlD *** To investigate the role of bioelectrical impedance-estimated visceral fat(VF)in assessing NAFlD *** In this cross-sectional study,patients with biopsy-proven NAFlD were prospectively *** patients underwent anthropometric evaluation,blood tests and bioelectrical impedance *** Between 2017 and 2020,119 patients were included[66.4%male,56 years(SD 10.7),62.2%obese,61.3%with metabolic syndrome].Sixty of them(50.4%)showed significant fibrosis(≥F2)in liver ***,VF and metabolic syndrome were associated with significant fibrosis(61 years vs 52 years,16.4 vs 13.1,73.3%vs 49.2%,respectively;Pll).In the multivariate analysis,VF and age were independently associated with significant fibrosis(VF,OR:1.11,95%CI:1.02-1.22,P=0.02;age,OR:1.08,95%CI:1.03-1.12,Pl including these variables showed and area under the receiver operating characteristic curve(AUROC)of 0.75,which was not inferior to transient elastography or NAFlD fibrosis score *** developed a nomogram including age and VF for assessing significant fibrosis in routine *** VF is a surrogate marker of liver fibrosis in patients with *** impedance analysis is an inexpensive and simple method that can be combined with age to guide patient referral when other resources may be unavailable.

关键词： Non-alcoholic fatty liver disease Visceral fat liver fibrosis Bioimpedanciometry Metabolic syndrome Obesity

Policy Iteration Algorithms for Zero-Sum Stochastic Differential Games with long-Run Average Payoff Criteria

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Journal of the Operations Research Society of China 2014年第4期2卷 395-421页

作者： joséDaniel lópez-Barrientos Faculty of Actuarial Sciences Universidad Ana´huacMe´xico NorteHuixquilucanMexico

This paper studies the policy iteration algorithm(PIA)for zero-sum stochastic differential games with the basic long-run average criterion,as well as with its more selective version,the so-called bias *** system is assumed to be a nondegenerate *** use lyapunov-like stability conditions that ensure the existence and boundedness of the solution to certain Poisson *** also ensure the convergence of a sequence of such solutions,of the corresponding sequence of policies,and,ultimately,of the PIA.

关键词： Ergodic payoff criterion Zero-sum stochastic differential games Policy iteration algorithm Nondegenerate diffusions Poisson equation Schäl convergence Bias game

p21 is necessary for the beneficial effects of fasting during chemotherapy

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Cancer Communications 2023年第1期43卷 164-168页

作者： Adrián Plaza Andrés Pastor-fernández josél.lópez-Aceituno Marta Barradas Cristina Pantoja Pablo J.fernandez-Marcos Metabolic Syndrome Group(BIOPROMET) Madrid Institute for Advanced Studies(IMDEA)FoodCEI UAM+CSICMadrid E28049Spain

Dear Editor,Short-term fasting(up to 48 hours)activates strong physiological and molecular responses[1].We and others showed a p53-independent transcriptional activation of the cell cycle inhibitor p21 upon fasting,most strongly in the liver,muscles,and many other tissues[2,3].Studies with mice[4,5]and human patients[6]have shown the beneficial effects of short-term fasting during anti-cancer chemotherapy treatments.

关键词： fasting chemotherapy p21

Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2019-2038页

作者： Benjamín Millán-Ramos Daniela Morquecho-Marín Phaedra Silva-Bermudez David Ramírez-Ortega Osmary Depablos-Rivera Julieta García-lópez Mariana fernández-lizárraga joséVictoria-Hernández Dietmar letzig Argelia Almaguer-Flores Sandra E.Rodil Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado en Ciencia e Ingeniería de Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina RegenerativaInstituto Nacional de Rehabilitación Luis Guillermo IbarraCDMX 14389Mexico Posgrado en Ciencias Médicas Odontológicas y de la SaludUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico Instituto de Ciencias Aplicadas y Tecnologia Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCDMX 11340Mexico Institute of Material and Process Design Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Magnesium Innovation Centre MagIC Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany laboratorio de Biointerfases Facultad de OdontologíaDivisión de Estudios de Posgrado e InvestigaciónUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico

Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be ***_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and *** this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was ***-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss *** results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the *** ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare ***,the ZrO_(2)coating prevents the adhesion and biofilm formation of ***.

关键词： Zirconium dioxide Magnetron sputtering Short-term degradation H_(2)evolution

Population structure and range expansion:the case of the invasive gastropod Cyclope neritea in northwest Iberian Peninsula

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Integrative Zoology 2012年第3期7卷 286-298页

作者： lucía COUCEIRO lúa lÓpez joséMiguel RUIZ Rodolfo BARREIRO Department of Ecology College of ScienceUniversity of A CoruñaA CoruñaSpain

Biotic invasions have a reputation for unpredictable ***,we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the *** neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic:the northwest Iberian Peninsula(NWIP)and the French Atlantic coast(FAC).Shellfish seabed farming is intense in both areas but focuses on different commercial *** mitochondrial gene sequences,the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the *** FAC,genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of *** at each site rather than with geographical *** this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave,a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent *** jump dispersal pattern of *** in the NWIP,together with the observation that populations established in the same year are genetically undifferentiated,point to human transport as the most plausible explanation for the current range *** evidence for human-mediated dispersal,*** managed to develop a seemingly non-random genetic pattern in the *** is suggested that caution must be exerted when interpreting genetic patterns in invaders.

关键词： alien species Cyclope neritea cytochrome oxidase I genetic geographic pattern population structure