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Friction 2019年第3期7卷 282-288页

作者： Rubén GONZáLEZ Diego RAMOS David BLANCO alfonso fernández-GONZáLEZ Jose L.VIESCA Mark HADFIELD Antolin HERNández BATTEZ Department of Marine Science and Technology University of OviedoAsturias 33203Spain Department of Construction and Manufacturing Engineering University of OviedoAsturias 33203Spain Department of Physical and Analytical Chemistry University of OviedoAsturias 33006Spain Department of Design and Engineering Bournemouth UniversityPoole BH12 5BBUK

The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing *** tests were completed for 90 minutes at room temperature and 100 °C in a reciprocating configuration at loads of 30 and 70 N,10 Hz-frequency,and 4 mm stroke *** volume was measured by confocal microscopy and the surface-IL interaction determined by *** main findings were that neat IL showed the best tribological behavior;the IL-containing mixture behaved similar to the base oil regarding friction,however outperformed the antiwear behavior of the base oil under higher temperature;surface-IL chemical interaction was found mainly at 100 °C.

关键词： ionic liquid additive friction wear polar oil

Inventory and Geometrical Changes in Small Glaciers Covering Three Northern Patagonian Summits Using Remote Sensing and GIS Techniques

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Journal of Mountain Science 2010年第1期7卷 26-35页

作者： alfonso fernández José Araos Jorge Marín Department of Geography Faculty of Architecture Urbanism and Geography Universidad de Concepción Centro de Estudios Avanzados en Zonas áridas (Ceaza)

In the last few decades, a large quantity of research has been performed to elucidate the current behavior of glaciers in southern Chile, especially with respect to the volumetric changes in the outlets of the Northern and Southern Patagonian Icefields （NPI and SPI, respectively）. Calculations have shown a generalized thinning and withdrawal, which greatly contributes to the increase in sea level attributed to the ice melt from non-polar glaciers. However, these icefields are surrounded by many small icecaps, which have＇yet to be studied in detail. A precise estimation of the volume of ice located in these mountain chains could provide new information with respect to this area＇s exact contribution to the increase in sea level. Thus, this study presents an inventory of relatively small Northern Patagonian glaciers in the surrounding of the three summits： Mount Queulat, and the Maca and Hudson volcanoes. The study used remote sensing techniques in a GIS environment to determine the margins, surface areas, thickness changes and hypsometry for the glaciated zones. Landsat images from different dates were analyzed using standard band ratio and screen delineation techniques. Additionally, digital elevation models from different dates were compared using map algebra, calculating thickness changes. Based on the results, we propose that there are important volumetric changes in the glaciers studied, whichcould be explained by precipitation trends in a general context, and an influence of the glaciers＇ sizes in some local response. Therefore, we suggest the exact contribution of the Patagonia to the increase in sea level corresponds to a regional pattern rather than just the behavior of a single ice field.

关键词： Glacier inventory thickness change digital elevation model morphometric measurement

Pre-fire aboveground biomass, estimated from LiDAR, spectral and field inventory data, as a major driver of burn severity in maritime pine (Pinus pinaster) ecosystems

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Forest Ecosystems 2022年第2期9卷 234-246页

作者： Jose Manuel fernandez-Guisuraga Susana Suarez-Seoane Paulo Mfernandes Victor fernandez-Garcia alfonso fernandez-Manso Carmen Quintano Leonor Calvo Area of Ecology Department of Biodiversity and Environmental ManagementFaculty of Biological and Environmental SciencesUniversity of Leon24071LeonSpain Centro de Investigacao e de Tecnologias Agroambientais e Biologicas Universidade de Tras-os-Montes e Alto Douro5000-801Vila RealPortugal Department of Organisms and Systems Biology(Ecology Unit)and Research Unit of Biodiversity(IMIB UO-CSIC-PA)University of OviedoOviedoMieresSpain Agrarian Science and Engineering Department School of Agricultural and Forestry EngineeringUniversity of Leon24400PonferradaSpain Electronic Technology Department School of Industrial EngineeringUniversity of Valladolid47011ValladolidSpain Sustainable Forest Management Research Institute University of Valladolid-Spanish National Institute for Agriculture and Food Research and Technology(INIA)34004PalenciaSpain

Background:The characterization of surface and canopy fuel loadings in fire-prone pine ecosystems is critical for understanding fire behavior and anticipating the most harmful ecological effects of ***,the joint consideration of both overstory and understory strata in burn severity assessments is often *** aim of this work was to assess the role of total,overstory and understory pre-fire aboveground biomass(AGB),estimated by means of airborne Light Detection and Ranging(LiDAR)and Landsat data,as drivers of burn severity in a megafire occurred in a pine ecosystem dominated by Pinus pinaster *** the western Mediterranean ***:Total and overstory AGB were more accurately estimated(R^(2) equal to 0.72 and 0.68,respectively)from LiDAR and spectral data than understory AGB(R^(2)=0.26).Density and height percentile LiDAR metrics for several strata were found to be important predictors of *** severity responded markedly and non-linearly to total(R^(2)=0.60)and overstory(R ^(2)=0.53)AGB,whereas the relationship with understory AGB was weaker(R ^(2)=0.21).Nevertheless,the overstory plus understory AGB contribution led to the highest ability to predict burn severity(RMSE=122.46 in dNBR scale),instead of the joint consideration as total AGB(RMSE=158.41).Conclusions:This study novelty evaluated the potential of pre-fire AGB,as a vegetation biophysical property derived from LiDAR,spectral and field plot inventory data,for predicting burn severity,separating the contri-bution of the fuel loads in the understory and overstory strata in Pinus pinaster *** evidenced relationships between burn severity and pre-fire AGB distribution in Pinus pinaster stands would allow the implementation of threshold criteria to support decision making in fuel treatments designed to minimize crown fire hazard.

关键词： Aboveground biomass Burn severity Landsat LiDAR Pinus pinaster

Communication between bone marrow mesenchymal stem cells and multiple myeloma cells:Impact on disease progression

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World Journal of Stem Cells 2023年第5期15卷 421-437页

作者： Daniel García-Sánchez Alberto González-González Ana alfonso-fernández Mónica Del Dujo-Gutiérrez Flor M Pérez-Campo Department of Molecular Biology_IDIVAL Faculty of MedicineUniversity of CantabriaSantander 39011CantabriaSpain Servicio de Traumatología y Cirugía Ortopédica Hospital Universitario Marqués de ValdecillaInstituto de Investigación Sanitaria Valdecilla(IDIVAL)Facultad de MedicinaUniversidad de CantabriaSantander 39008CantabriaSpain

Multiple myeloma(MM)is a hematological malignancy characterized by the accumulation of immunoglobulin-secreting clonal plasma cells at the bone marrow(BM).The interaction between MM cells and the BM microenvironment,and specifically BM mesenchymal stem cells(BM-MSCs),has a key role in the pathophysiology of this *** data support the idea that BM-MSCs not only enhance the proliferation and survival of MM cells but are also involved in the resistance of MM cells to certain drugs,aiding the progression of this hematological *** relation of MM cells with the resident BM-MSCs is a two-way *** modulate the behavior of BM-MSCs altering their expression profile,proliferation rate,osteogenic potential,and expression of senescence *** turn,modified BM-MSCs can produce a set of cytokines that would modulate the BM microenvironment to favor disease *** interaction between MM cells and BM-MSCs can be mediated by the secretion of a variety of soluble factors and extracellular vesicles carrying microRNAs,long non-coding RNAs or other ***,the communication between these two types of cells could also involve a direct physical interaction through adhesion molecules or tunneling ***,understanding the way this communication works and developing strategies to interfere in the process,would preclude the expansion of the MM cells and might offer alternative treatments for this incurable disease.

关键词： Multiple myeloma Mesenchymal stem cells Bone marrow microenvironment Soluble factors Extra-cellular vesicles Cells adhesion molecules Tunnellingnanotubes

Step-by-Step Building of a Four Dimensional Fatigue Compatible Regression Model including Frequencies

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Open Journal of Statistics 2021年第6期11卷 1072-1096页

作者： Enrique Castillo alfonso fernández-Canteli Sergio Blasón Golta Khatibi Bernhard Czerny Mohammad Zareghomsheh Spanish Royal Academy of Engineering Madrid Spain Spanish Royal Academy of Sciences Madrid Spain Department of Construction and Engineering Manufacturing Polytechnic School of Gijón University of Oviedo Campus de Viesques Asturias Spain Bundesanstalt für Materialforschung und Prüfung (BAM) Berlin Germany Department 9-Component Safety Division 9.4 Weld Mechanics Berlin Germany Christian Doppler Laboratory for Lifetime and Reliability of Interfaces in Complex Multi-Material Electronics Chemical Technologies and Analytics Vienna Austria

The purpose of this research is to develop a model, with emphasis on compatibility conditions and model building, valid for high cycle fatigue design components such as wind turbines, automobiles, high speed railways and aeronautical material. In this work, we have added the frequency as one more variable to an existing fatigue model that already includes maximum stress, stress ratio and lifetime. As a result, a model and estimation method has been proposed and a random variable V has been identified, which, allows the accumulated damage and the probability of failure to be assessed for any load history in terms of stress levels, stress ranges and frequencies. Finally, the model is validated using a large set of real experimental data.

关键词： Compatibility Conditions Cumulative Damage Frequency Effect Functional Equations Regression Model

Using fused filament fabrication to improve the tribocorrosion behaviour of 17-4 PH SS in comparison to other metal forming techniques

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Friction 2024年第10期12卷 2325-2343页

作者： Cristina GARCÍA-CABEZÓN Juan alfonso NARANJO Celia GARCÍA-HERNÁndez Cristina BERGES Gemma HERRANZ fernando MARTÍN-PEDROSA Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain INEI-Escuela Técnica Superior de Ingeniería Industrial(ETSII) Universidad de Castilla La ManchaCastilla-La Mancha 13071Spain

Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and *** technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and ***,both technologies provide near-dense *** work presents an in-depth study of the processing method’s *** porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)*** samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM ***,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure.

关键词： 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour

An innovative heterogeneous transfer learning framework to enhance the scalability of deep reinforcement learning controllers in buildings with integrated energy systems

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Building Simulation 2024年第5期17卷 739-770页

作者： Davide Coraci Silvio Brandi Tianzhen Hong alfonso Capozzoli Politecnico di Torino Department of EnergyTEBE research groupBAEDA Lab.Corso Duca degli Abruzzi 24Torino10129Italy Building Technology and Urban Systems Division Lawrence Berkeley National LaboratoryOne Cyclotron RoadBerkeleyCA 94720USA

Deep Reinforcement Learning(DRL)-based control shows enhanced performance in the management of integrated energy systems when compared with Rule-Based Controllers(RBCs),but it still lacks scalability and generalisation due to the necessity of using tailored models for the training *** Learning(TL)is a potential solution to address this ***,existing TL applications in building control have been mostly tested among buildings with similar features,not addressing the need to scale up advanced control in real-world scenarios with diverse energy *** paper assesses the performance of an online heterogeneous TL strategy,comparing it with RBC and offline and online DRL controllers in a simulation setup using EnergyPlus and *** study tests the transfer in both transductive and inductive settings of a DRL policy designed to manage a chiller coupled with a Thermal Energy Storage(TES).The control policy is pre-trained on a source building and transferred to various target buildings characterised by an integrated energy system including photovoltaic and battery energy storage systems,different building envelope features,occupancy schedule and boundary conditions(e.g.,weather and price signal).The TL approach incorporates model slicing,imitation learning and fine-tuning to handle diverse state spaces and reward functions between source and target *** show that the proposed methodology leads to a reduction of 10% in electricity cost and between 10% and 40% in the mean value of the daily average temperature violation rate compared to RBC and online DRL ***,online TL maximises self-sufficiency and self-consumption by 9% and 11% with respect to ***,online TL achieves worse performance compared to offline DRL in either transductive or inductive ***,offline Deep Reinforcement Learning(DRL)agents should be trained at least for 15 episodes to reach the same level of performance as the online

关键词： transfer learning reinforcement learning building control building energy management

Autonomous Vehicle Platoons In Urban Road Networks:A Joint Distributed Reinforcement Learning and Model Predictive Control Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 141-156页

作者： Luigi D’alfonso Francesco Giannini Giuseppe Franzè Giuseppe Fedele Francesco Pupo Giancarlo Fortino IEEE the Department of Computer Engineering ModelingElectronics and SystemsUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy the Department of Mechanical Engineering Energy Engineering and ManagementUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy

In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framework:the deep reinforcement learning output(action) is translated into a set-point to be tracked by the model predictive controller;conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decisionmaking purposes;on the other hand, time-varying hard constraints are always satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps(links,junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed with the a

关键词： Distributed model predictive control distributed reinforcement learning routing decisions urban road networks

A new oxidative pathway of nitric oxide production from oximes in plants

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Molecular Plant 2024年第1期17卷 178-198页

作者： Pedro Lopez-Gomez Javier Buezo Marina Urra alfonso Cornejo Raquel Esteban Jorge fernandez de los Reyes Estibaliz Urarte Estefania Rodriguez-Dobreva Alejandro Chamizo-Ampudia Alejandro Eguaras Sebastian Wolf Daniel Marino Victor Martinez-Merino Jose F.Moran Institute for Multidisciplinary Research in Applied Biology(IMAB) Department of SciencesPublic University of Navarre(UPNA)Avda.de Pamplona 12331192 MutilvaSpain Institute for Advanced Materials and Mathematics(INAMAT2) Department of SciencesPublic University of Navarre(UPNA)Campus de Arosadia31006 PamplonaSpain Department of Plant Biology and Ecology University of the Basque Country(UPV/EHU)Sarriena s/nApdo.64448080 BilbaoSpain Center for Plant Molecular Biology(ZMBP) University of TubingenGeschwister-Scholl-Platz72074 TubingenGermany Institute of Natural Resources and Agrobiology of Salamanca(IRNASA) Department of Plant-Microorganism InteractionsSpanish National Research Council(CSIC)Cordel de Merinas40-5237008SalamancaSpain Department of Biochemistry Area of Molecular BiologyVeterinary FacultyUniversity of LeonCampus de Vegazanas/n.24071 LeonSpain

Nitric oxide(NO)is an essential reactive oxygen species and a signal molecule in *** several studies have proposed the occurrence of oxidative NO production,only reductive routes for NO production,such as the nitrate(NO_(3)^(-))-upper-reductase pathway,have been evidenced to date in land ***,plants grown axenically with ammonium as the sole source of nitrogen exhibit contents of nitrite and NO3−,evidencing the existence of a metabolic pathway for oxidative production of *** hypothesized that oximes,such as indole-3-acetaldoxime(IAOx),a precursor to indole-3-acetic acid,are intermediate oxidation products in NO *** detected the production of NO from IAOx and other oximes catalyzed by peroxidase(POD)enzyme using both 4-amino-5-methylamino-2′,7′-difluorescein fluorescence and *** stimulated the reaction,while superoxide dismutase inhibited ***,mouse NO synthase can also use IAOx to produce NO at a lower rate than *** provided a full mechanism for POD-dependent NO production from IAOx consistent with the experimental data and supported by density functional theory *** showed that the addition of IAOx to extracts from Medicago truncatula increased the in vitro production of NO,while in vivo supplementation of IAOx and other oximes increased the number of lateral roots,as shown for NO donors,and a more than 10-fold increase in IAOx dehydratase ***,we found that in vivo supplementation of IAOx increased NO production in Arabidopsis thaliana wild-type plants,while prx33-34 mutant plants,defective in POD33-34,had reduced *** data show that the release of NO by IAOx,as well as its auxinic effect,explain the superroot ***,our study reveals that plants produce NO utilizing diverse molecules such as oximes,POD,and flavins,which are widely distributed in the plant kingdom,thus introducing a long-awaited oxidative pathway to NO production in plants.T

关键词： ammonium oxidation auxin nitric oxide oxime peroxidase root phenotype

Polyoxidovanadates a new therapeutic alternative for neurodegenerative and aging diseases

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Neural Regeneration Research 2024年第3期19卷 571-577页

作者： Sonia Irais Gonzalez-Cano Gonzalo Flores Jorge Guevara Julio Cesar Morales-Medina Samuel Treviño alfonso Diaz Faculty of Chemical Sciences Benemerita Autonomous University of PueblaPueblaMexico Institute of Physiology Benemerita Autonomous University of PueblaPueblaMexico Department of Biochemistry Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Animal Reproduction Research Center CINVESTAV-Autonomous University of TlaxcalaTlaxcalaMexico

Aging is a natural phenomenon characterized by a progressive decline in physiological integrity,leading to a deterioration of cognitive function and increasing the risk of suffering from chronic-degenerative diseases,including cardiovascular diseases,osteoporosis,cancer,diabetes,and *** is considered the major risk factor for Parkinson’s and Alzheimer’s disease ***,diabetes and insulin resistance constitute additional risk factors for developing neurodegenerative ***,no treatment can effectively reverse these neurodegenerative ***,some antidiabetic drugs have opened the possibility of being used against neurodegenerative *** the previous framework,Vanadium species have demonstrated a notable antidiabetic *** research group evaluated polyoxidovanadates such as decavanadate and metforminium-decavanadate with preventive and corrective activity on neurodegeneration in brain-specific areas from rats with metabolic *** results suggest that these polyoxidovanadates induce neuronal and cognitive restoration *** review aims to describe the therapeutic potential of polyoxidovanadates as insulin-enhancer agents in the brain,constituting a therapeutic alternative for aging and neurodegenerative diseases.

关键词： Alzheimer’s disease antidiabetic brain cognition diabetes insulin neurodegeneration neuroinflammation oxidative stress Vanadium species