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sliding response of gravity dams including vertical seismic accelerations

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 189-200页

作者： Constantin Christopoulos PierreLéger andré Filiatrault Department of Civil Engineering University of TorontoCanada Assistant Professor Department of Civil Engineering Ecole PolytechniqueMontrealCanada Professor Department of Civil Structural and Environmental EngineeringUniversity at BuffaloUSA Professor

seismic safety assessment of gravity dams has become a major concern in many regions of the world while the effects of vertical seismic accelerations on the response of structures remain poorly *** paper first investigates the effect of including vertical accelerations in the sliding response analysis of gravity dams subjected to a range of historical ground motion records separated in two groups according to their source-to-site *** showed that the incidence of vertical accelerations on the sliding response of gravity dams is significantly higher for near-source records than for far- source *** pseudo-static 30% load combination rule,commonly used in practice to account for the non-simultaneous occurrence of the peak horizontal and vertical accelerations,yielded good approximations of the minimum safety factors against sliding computed from time-history analyses.A method for empirically estimating the vertical response spectra based on horizontal spectra,accounting for the difference in frequency content and amplitudes between the two components is *** from analyses using spectrum compatible horizontal and vertical synthetic records also approximated well the sliding response of a gravity dam subjected to series of simultaneous horizontal and vertical historical earthquake records.

关键词： vertical accelerations sliding gravity dams synthetic accelerograms pseudo-static combinations frequency

self-formation of hexagonal nanotemplates for growth of pyramidal quantum dots by metalorganic vapor phase epitaxy on patterned substrates

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Nano Research 2016年第11期9卷 3279-3290页

作者： Alessandro surrente Romain Carron Pascal gallo Alok Rudra Benjamin Dwir Eli Kapon Laboratory of Physics of Nanostructures Ecole Polytechnique Federale de Lausanne CH- 1015 Lausanne Switzerland

We demonstrate the self-formation of hexagonal nanotemplates on GaAs （111）B substrates patterned with arrays of inverted tetrahedral pyramids during metal-organic vapor phase epitaxy and its role in producing high-symmetry, site-controlled quantum dots （QDs）. By combining atomic force microscopy measurements on progressively thicker GaAs epitaxial layers with kinetic Monte Carlo growth simulations, we demonstrate self-maintained symmetry elevation of the QD formation sites from three-fold to six-fold symmetry. This symmetry elevation stems from adatom fluxes directed towards the high-curvature sites of the template, resulting in the formation of a fully three-dimensional hexagonal template after the deposition of relatively thin GaAs layers. We identified the growth conditions for consistently achieving a hexagonal pyramid bottom, which are useful for producing high-symmetry QDs for efficient generation of entangled photons.

关键词： metalorganic vapor phaseepitax kinetic Monte Carlosimulations epitaxial growth onpatterned substrates symmetry elevation adatom diffusion

Measuring the model risk-adjusted performance of machine learning algorithms in credit default prediction

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Financial Innovation 2022年第1期8卷 1930-1964页

作者： andrés Alonso Robisco JoséManuel CarbóMartínez Banco de España Calle de Alcalá4828014 MadridSpain

Implementing new machine learning(ML)algorithms for credit default prediction is associated with better predictive performance;however,it also generates new model risks,particularly concerning the supervisory validation *** industry surveys often mention that uncertainty about how supervisors might assess these risks could be a barrier to *** this study,we propose a new framework to quantify model risk-adjustments to compare the performance of several ML *** address this challenge,we first harness the internal ratings-based approach to identify up to 13 risk components that we classify into 3 main categories—statistics,technology,and market ***,to evaluate the importance of each risk category,we collect a series of regulatory documents related to three potential use cases—regulatory capital,credit scoring,or provisioning—and we compute the weight of each category according to the intensity of their mentions,using natural language processing and a risk terminology based on expert ***,we test our framework using popular ML models in credit risk,and a publicly available database,to quantify some proxies of a subset of risk factors that we deem *** measure the statistical risk according to the number of hyperparameters and the stability of the *** technological risk is assessed through the transparency of the algorithm and the latency of the ML training method,while the market conduct risk is quantified by the time it takes to run a post hoc technique(sHapley Additive exPlanations)to interpret the output.

关键词： Artificial intelligence Machine learning Credit risk Interpretability Bias Internal ratings based model IRB model Natural language processing NLP

Lipid scrambling in immunology:why it is important

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Cellular & Molecular Immunology 2023年第9期20卷 1081-1083页

作者： Ning Wu andréVeillette The First Affiliated Hospital of Anhui Medical University Clinical Immunology InstituteAnhui Medical UniversityHefeiAnhuiChina Laboratory of Molecular Oncology Institut de recherches cliniques de Montréal(IRCM)MontréalQC H2W1R7Canada Department of Medicine University of MontréalMontréalQC H3T 1J4Canada Department of Medicine McGill UniversityMontréalQC H3G 1Y6Canada

Asymmetric lipid distribution in the plasma membrane(PM)is one of the fundamental features of living *** not only serve as structural components of the biophysical structure of the PM that preserves cell integrity but also participate directly in *** phospholipids(PLs),such as phosphatidylserine(Ps),phosphatidylethanolamine(PE),and phosphoinositol(PI),are preferentially located in the inner layer of the PM,creating electrostatic charges for the docking of membrane-associated and cytoplasmic proteins carrying polybasic stretches of amino ***,there is emerging evidence that reversible changes in the distribution of these lipids take place in the PM and that these changes are critical for normal cell signaling,functions and homeostasis[1–3].They can also be implicated in the genesis of pathologies.

关键词： electrostatic reversible distribution

Gut-liver axis in sepsis-associated liver injury:Epidemiology,challenges and clinical practice

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World Journal of Gastroenterology 2025年第1期31卷 163-166页

作者： Fabiana andréa Moura Aryana Isabelle de Almeida Neves siqueira College of Nutrition Federal University of AlagoasMaceio 57072-970AlagoasBrazil College of Medicine Federal University of AlagoasMaceio 57072-970AlagoasBrazil

Although the liver has a remarkable regenerative capacity,sepsis-associated liver injury(sLI)is a complication often seen in intensive care *** to its role in immune and inflammatory regulation,the liver is particularly vulnerable during severe *** the global prevalence,causes,and management of sLI is essential to improve outcomes and reduce healthcare *** paper aims to explore these factors,with an emphasis on identifying effective strategies for clinical *** et al’s bibliometric analysis of 787 publications(745 original articles and 42 reviews,mostly in animal models)from 2000 to 2023 highlights the growing interest in sLI,focusing on oxidative stress,gut microbiota,and inflammatory *** components such as nuclear factor-kappa B and the NOD-like receptor thermal protein domain associated protein 3 inflammasome pathway,along with their links to gut microbiota imbalance and oxidative stress,are crucial for understanding sLI *** gut-liver axis,particularly the role of intestinal permeability and bacterial translocation in liver inflammation,is *** this context,bacterial translocation is especially relevant for critically ill patients,as it can exacerbate liver *** findings underscore the need for integrated care in intensive care units,prioritizing gut health and careful antibiotic use to prevent *** extensive research,there remains a lack of clinical trials to validate therapeutic *** abundance of experimental studies highlights potential therapeutic targets,stressing the need for high-quality randomized clinical trials to translate these findings into clinical practice.

关键词： Dysbiosis Oxidative stress Inflammation Microbiota sepsis-associated liver injury

Bleeding risk assessment in elderly patients with acute coronary syndrome

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Journal of Geriatric Cardiology 2019年第2期16卷 145-150页

作者： Lucía Riobóo-Lestón sergio Raposeiras-Roubin Emad Abu-Assi andrés I?iguez-Romo Department of Cardiology University Hospital álvaro Cunqueiro

Nowadays,elderly people represent a growing population segment with a well known increased risk of both ischemic and bleeding *** acute coronary syndrome guidelines,strongly recommend dual antiplatelet therapy(DAPT)with few specific references for aged patients due to lack of *** aged>75 years are misrepresented in the classic derivation trials *** to reduce the bleeding risk in this group of patients are urgently needed for the daily clinical *** the specific age related bleeding risk factors and the importance of an integral geriatric assessment remains *** of the available in-hospital and out-hospital bleeding risk scores have shown a lower to moderate predictive ability in older patients and no specific tools are developed in elderly *** importance of an appropriate vascular access choice,type and duration of antiplatelet drugs is crucial to reduce the bleeding *** radial approaches and short DAPT duration leads to reduce *** interesting subgroup of patients is those who need chronic anticoagulation therapy after percutaneous coronary intervention,due to their very high risk of *** alternatives as dual therapy with oral anticoagulation and only one antiplatlet drug should be *** current review,we evaluate the available evidence about bleeding risk in elderly.

关键词： Acute coronary syndrome Bleeding risk Dual antiplatelet treatment Elderly patients

Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás Gloria P.Moreno Francisco J.Aparicio Ángel Barranco andrés Castellanos Gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain Departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle *** remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon ***,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification *** this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D *** approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation *** results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability

Atacama Field Campaign: laboratory and in-situ measurements for remote sensing applications

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International Journal of Digital Earth 2019年第1期12卷 43-61页

作者： Cristian Mattar andrés santamaría-Artigas Flavio Ponzoni Cibele T.Pinto Carolina Barrientos Glynn Hulley Laboratory for Analysis of the Biosphere(LAB) University of ChileSantiagoChile Department of Geographical sciences University of MarylandCollege ParkMDUSA Divisão de sensoriamento Remoto(DsR) Instituto Nacional de Pesquisas Espaciais(INPE)São PauloBrasil Aerial Photogrammetric service(sAF) Chilean Air ForceSantiagoChile Jet Propulsion Laboratory(JPL) California Institute of TechnologyPasadenaCAUSA

This work presents the preliminary results of the first field calibration campaign performed in the Atacama Desert,Chile,between the 18 and 22 August 2014,called the Atacama Field Campaign(ATAFIC 2014).In situ measurements were performed in order to spectrally characterize the surface reflectance spectra between 0.3 and 2.5μm,radiometric temperature(8.0–14.0μm)and atmospheric measurements.A soil sample was collected and analyzed using Fourier Transform Infrared spectroscopy and X-Ray Diffraction techniques to characterize the surface reflectance spectra and mineralogical composition,*** land surface emissivity in addition to GOEs,MODIs and Landsat-8 land surface temperature(LsT)were also *** showed that the spectral features of the Atacama soil and the characteristics of this geographical zone,which is featured as the most hyper-arid and cloudless place in the world,make this area a potential target for surface reflectance *** and night LsT comparison between field and remote sensing data are lower than 2 K and the Root Mean square Error for land surface emissivity is close to 2%.This work opens the possibilities to consider the Atacama Desert as a reference target for calibration and validation activities for earth observation missions’purposes.

关键词： Atacama spectroradiometry emissivity temperature surface reflectance

Developing biophilic intermediate spaces for Arctic housing:Optimizing the thermal,visual,and energy performance

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Building simulation 2024年第6期17卷 857-875页

作者： Tarlan Abazari andréPotvin Louis Gosselin Claude MH Demers GRAP(Groupe de recherche en ambiance physiques) School of ArchitectureLaval UniversityQuébecCanada Department of Mechanical Engineering Faculty of Science and EngineeringLaval UniversityQuébecCanada

Connecting occupants to the outdoor environment and incorporating biophilic design principles are challenging in extreme Arctic climatic *** Arctic housing models do not provide efficient thermal and daylight transitions which are essential for the well-being and cultural needs of their *** address these challenges,this research develops free-running biophilic intermediate spaces,integrated into an existing Arctic housing *** simulation methods are employed to optimize the primary and secondary architectural design variables for 26 case studies of intermediate *** variables include volume,transparency ratio,and *** variables include materials and physical ***,Daylight Factor/Autonomy,and Energy Use are evaluated as performance *** reveal that free-running intermediate spaces with 6 meters depth and a transparency ratio above 50%provide efficient indoor–outdoor transitions regarding thermal,visual,and energy *** architectural configurations contribute to an approximately 5%reduction in energy consumption within the housing unit compared to the *** side windows prevents the risk of overheating during the summer by reducing the average indoor temperature of intermediate spaces by 7°C but increases the overall energy *** a potential alternative to double-glazing,polycarbonate sheets enable efficient thermal performance by increasing the average indoor temperature of intermediate spaces by approximately 15°C during the cold Arctic *** polycarbonate sheets results in a 16.6%reduction in energy consumption compared to using double-glazing material in intermediate space,and a 26%reduction from the *** outcomes contribute to efficient indoor–outdoor connections and energy efficiency in Arctic housing.

关键词： Arctic housing intermediate spaces biophilic design positive thermal transitions daylight availability energy efficiency