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Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 921-935页

作者： a.colaço P.Alves Costa C.Ferreira C.Parente J.Fernandez-Ruiz CoNSTRUCT-FEUP University of PortoRua Dr.Roberto Frias4200-465 PortoPortugal University of La Coruña Department of Civil EngineeringCampus de Elviña 15071La CoruñaSpain

Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the ground.Impact pile driving is an interesting and viable solution from economic and technical points of view.However,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately met.For this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear methodology.Given the complexity of the problem,an experimental test site was developed and fully characterized.The experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile driving.The comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile driving.The experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models.

关键词： pile driving ground-borne vibrations numerical modeling experimental validation

Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes Virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEoSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and breccias.This particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore minerals.Electron probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and pyrite.Fluid inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 m.This particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

3D Monte-Carlo model to study the transport of hot electrons in the context of inertial confinement fusion. Part Ⅱ

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Matter and Radiation at Extremes 2022年第6期7卷 64-75页

作者： A.Tentori a.colaïtis D.Batani Centre Lasers Intenses et Applications CELIAUniversitéBordeaux CEA-CNRSUMR 5107F-33405 TalenceFrance

We describe two numerical investigations performed using a 3D plasma Monte-Carlo code,developed to study hot-electron transport in the context of inertial confinement fusion.The code simulates the propagation of hot electrons in ionized targets,using appropriate scattering differential cross sections with free plasma electrons and ionized or partially ionized atoms.In this paper,we show that a target in the plasma state stops and diffuses electrons more effectively than a cold target(i.e.,a target under standard conditions in which ionization is absent).This is related to the fact that in a plasma,the nuclear potential of plasma nuclei has a greater range than in the cold case,where the screening distance is determined by the electronic structure of atoms.However,in the ablation zone created by laser interaction,electrons undergo less severe scattering,counterbalancing the enhanced diffusion that occurs in the bulk.We also show that hard collisions,i.e.,collisions with large polar scattering angle,play a primary role in electron beam diffusion and should not be neglected.An application of the plasma MonteCarlo model to typical shock ignition implosions suggests that hot electrons will not give rise to any preheating concerns if their Maxwellian temperature is lower than 25–30 keV,although the presence of populations at higher temperatures must be suppressed.This result does not depend strongly on the initial angular divergence of the electron beam set in the simulations.

关键词： electrons diffusion neglected

Rethinking phonons:The issue of disorder

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npj Computational Materials 2017年第1期3卷 44-51页

作者： Hamid Reza Seyf Luke Yates Thomas L.Bougher Samuel Graham Baratunde a.cola Theeradetch Detchprohm Mi-Hee Ji Jeomoh Kim Russell Dupuis Wei Lv Asegun Henry George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGAUSA Heat Lab Georgia Institute of TechnologyAtlantaGAUSA School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGAUSA School of Electrical Engineering and Computer Science Georgia Institute of TechnologyAtlantaGAUSA

Current understanding of phonons treats them as plane waves/quasi-particles of atomic vibration that propagate and scatter.The problem is that conceptually,when any level of disorder is introduced,whether compositional or structural,the character of vibrational modes in solids changes,yet nearly all theoretical treatments continue to assume phonons are still waves.For example,the phonon contributions to alloy thermal conductivity(TC)rely on this assumption and are most often computed from the virtual crystal approximation(VCA).Good agreement is obtained in some cases,but there are many instances where it fails—both quantitatively and qualitatively.Here,we show that the conventional theory and understanding of phonons requires revision,because the critical assumption that all phonons/normal modes resemble plane waves with well-defined velocities is no longer valid when disorder is introduced.Here we show,surprisingly,that the character of phonons changes dramatically within the first few percent of impurity concentration,beyond which phonons more closely resemble the modes found in amorphous materials.We then utilize a different theory that can treat modes with any character and experimentally confirm its new insights.

关键词： alloy character utilize

Application of light detection and ranging and ultrasonic sensors to high-throughput phenotyping and precision horticulture: current status and challenges

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Horticulture Research 2018年第1期5卷 480-490页

作者： AndréF.colaço JoséP.Molin Joan R.Rosell-Polo Alexandre Escolà Biosystems Engineering Department “Luiz de Queiroz”College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba-SP13418-900Brazil Research Group on AgroICT and Precision Agriculture Department of Agricultural and Forest EngineeringSchool of Agrifood and Forestry Science and EngineeringUniversity of Lleida–Agrotecnio CenterAv.Rovira Roure19125198LleidaCataloniaSpain CSIRo Waite CampusLocked Bag 2Glen OsmondSA5064Australia

Ultrasonic and light detection and ranging(LiDAR)sensors have been some of the most deeply investigated sensing technologies within the scope of digital horticulture.They can accurately estimate geometrical and structural parameters of the tree canopies providing input information for high-throughput phenotyping and precision horticulture.A review was conducted in order to describe how these technologies evolved and identify the main investigated topics,applications,and key points for future investigations in horticulture science.Most research efforts have been focused on the development of data acquisition systems,data processing,and high-resolution 3D modeling to derive structural tree parameters such as canopy volume and leaf area.Reported applications of such sensors for precision horticulture were restricted to real-time variable-rate solutions where ultrasonic or LiDAR sensors were tested to adjust plant protection product or fertilizer dose rates according to the tree volume variability.More studies exploring other applications in site-specific management are encouraged;some that integrates canopy sensing data with other sources of information collected at the within-grove scale(e.g.,digital elevation models,soil type maps,historical yield maps,etc.).Highly accurate 3D tree models derived from LiDAR scanning demonstrate their great potential for tree phenotyping.However,the technology has not been widely adopted by researchers to evaluate the performance of new plant varieties or the outcomes from different management practices.Commercial solutions for tree scanning of whole groves,orchards,and nurseries would promote such adoption and facilitate more applied research in plant phenotyping and precision horticulture.

关键词： culture LiDAR maps

Review on the management of cardiovascular risk factors in the elderly

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Journal of Geriatric Cardiology 2022年第11期19卷 894-927页

作者： Magali González-colaço Harmand María del Mar García-Sanz Antònia Agustí Pablo César Prada-Arrondo Alberto Domínguez-Rodríguez Beatriz Grandal-Leirós David Peña-otero Natalia Negrín-Mena Jesús Javier López-Hernández Pablo Díez-Villanueva Department of Internal Medicine-Geriatric Medicine Hospital Universitario Nuestra Señora de CandelariaSanta Cruz de TenerifeSpain Universidad Europea de Canarias Faculty of Health SciencesLa OrotavaSpain Clinical Pharmacology Department Hospital Universitario Marqués de ValdecillaSantanderSpain Clinical Pharmacology Department.Hospital Vall d'Hebron BarcelonaSpain Cardiac Surgery Department Hospital Universitario de CanariasLa LagunaTenerifeSpain Cardiology Department Hospital Universitario de CanariasLa LagunaTenerifeSpain ortogeriatric Department.Hospital Universitario de Canarias La LagunaTenerifeSpain Subdepartment of Health Care Hospital Universitario Marqués de ValdecillaServicio Cántabro de SaludSantanderSpain Instituto de Investigación Sanitaria Gregorio Marañón(liSGM)y Valdecilla(IDIVAL) Spain Hospital Universitario de Canarias Sistema Canario de SaludTenerifeSpain Primary Care Management Servicio Cántabro de SaludSpain Cardiology Department Hospital de la PrincesaMadridSpain

Cardiovascular risk factors(CVRF)are very prevalent in the elderly population and in addition to predisposing to cardiovascular disease they are related to functional decline,which limits the quality of life in this population.The objective of this work is to offer a review of the current evidence in the management of CVRF in the elderly population.The search strategy was executed in PubMed,*** and Embase,to search for clinical trials,observational cohort or cross-sectional studies,reviews,and clinical practice guidelines focused or including elderly population.The results provided were refined after reading the title and abstract,as well as elimination of duplicates,and were finally identified and assessed following the GRADE methodology.A total of 136 studies were obtained for all predefined risk factors,such as sedentary lifestyle,smoking,obesity and metabolic syndrome,hypertension,diabetes mellitus,dyslipidemia and alcohol.We described the results of the studies identified and assessed according to their methodological quality in different recommendation sections:diagnostic and prevention,intervention,or treatment in the elderly population.As the main limitation to the results of this review,there is the lack of quality studies whose target population is elderly patients.This issue limits the recommendations that can be made in this population.Due to this reason,comprehensive geriatric assessment seems the best tool currently available to implement the most appropriate treatment plans based on the baseline situation and comorbidity of each elderly patient.

关键词： prevention elderly finally

Different risk factors influence peptic ulcer disease development in a Brazilian population

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World Journal of Gastroenterology 2012年第38期18卷 5404-5411页

作者： Rodrigo Buzinaro Suzuki Rodrigo Faria.cola Larissa Tranquilino Bardela.cola Camila Garcia Ferrari Fred Ellinger Altino Luiz Therezo Luis Carlos da Silva André Eterovic Márcia Aparecida Sperana Department of Genotyping Hemocenter Marilia Medical School Marilia 17519-030 So Paulo Brazil Center for Natural and Human Sciences Universidade Federal do ABC Santo André 09210-170 So Paulo Brazil Department of Molecular Biology Marilia Medical School Marilia 17519-030 So Paulo Brazil Department of Pathology Marilia Medical School Marilia 17519-030 So Paulo Brazil

AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic patients.tients submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA ) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients. RESULTS: of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall c 2 = 2.1, P = 0.3423). Sex [odds ratios (oR) = 1.8631, P = 0.0058] but not age (oR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall c 2 = 30.5, P opathological results showed a significant contribution of ageing for both atrophy (oR = 1.0297, P oR = 1.0520, P of H. pylori was significantly associated with decreasing age (oR = 0.9827, P of DU (oR = 3.6077, P of m1 in DU was statistically significant (oR = 2.3563, P = 0.0018) but not in CG (oR = 2.678, P = 0.0863) and GU (oR = 1.520, P = 0.2863). CoNCLUSIoN: In our p

关键词：消化性溃疡人口发展溃疡病风险因素 Logistic回归分析巴西幽门螺旋杆菌幽门螺杆菌

Evolving role of FDG-PET/CT in prognostic evaluation of resectable gastric cancer

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World Journal of Gastroenterology 2017年第38期23卷 6923-6926页

作者： Emilio De Raffele Mariateresa Mirarchi Dajana Cuicchi Ferdinando Lecce Bruno cola Unità operativa di Chirurgia Generale Dipartimento dell’Apparato Digerente Azienda Ospedaliero-Universitaria di Bologna U.o. di Chirurgia Generale Dipartimento Strutturale Chirurgico Ospedale 'SS Antonio e Margherita'

Gastric cancer(GC) remains a leading cause of cancer death worldwide. Radical gastrectomy is the only potentially curative treatment, and perioperative adjuvant therapies may improve the prognosis after curative resection. Prognosis largely depends on the tumour stage and histology, but the host systemic inflammatory response(SIR) to GC may contribute as well, as has been determined for other malignancies. In GC patients, the potential utility of positron emission tomography/computed tomography(PET/CT) with the imaging radiopharmaceutical 18F-fluorodeoxyglucose(FDG) is still debated, due to its lower sensitivity in diagnosing and staging GC compared to other imaging modalities. There is, however, growing evidence that FDG uptake in the primary tumour and regional lymph nodes may be efficient for predicting prognosis of resected patients and for monitoring tumour response to perioperative treatments, having prognostic value in that it can change therapeutic strategies. Moreover, FDG uptake in bone marrow seems to be significantly associated with SIR to GC and to represent an efficient prognostic factor after curative surgery. In conclusion, PET/CT technology is efficient in GC patients, since it is useful to integrate other imaging modalities in staging tumours and may have prognostic value that can change therapeutic strategies. With ongoing improvements, PET/CT imaging may gain further importance in the management of GC patients.

关键词：胃的癌症预后 18 F-fluorodeoxyglucose 正电子排放计算断层摄影术的断层摄影术骨头髓

SMART CoMMUNICATIoNS AND NETWoRKING FoR FUTURE DEEP-SPACE EXPLoRATIoN

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China Communications 2020年第7期17卷 I0001-I0004页

作者： Qinyu Zhang Zhili Sun Tomaso de cola Kanglian Zhao the EIE School the Institute for Communication Systems(ICS) Department of Electrical and Electronic EngineeringFaculty of Engineering and Physical SciencesUniversity of Surrey the German Aerospace Center(DLR) the Satellite and Space Communications(SSC)technical committee within ComSoc the Space-Internetworking Services(SIS)within the CCSDS standardization body the SatCom working group within the ETP Networld2020 platform School of Electronic Science and Engineering Nanjing University Institute of Space-Terrestrial Intelligent Networks Nanjing University

Since the first space probe flew to the Moon in 1959,over 200 deep-space exploration missions have already been carried out on the eight planets,various asteroids and comets in the solar system.Amount of deepspace sci... 详细信息

关键词： SPACE planet NETWoRK