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Cosmological parameter estimation from large-scale structure deep learning

Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 36-50页

作者： ShuYang Pan MiaoXin Liu Jaime Forero-Romero cristiano g.sabiu Zhigang Li HaiTao Miao Xiao-Dong Li School of Physics and Astronomy Sun Yat-Sen UniversityGuangzhou 510297China Departamento de Física Universidad de los AndesBogotáCP 111711Colombia Department of Astronomy Yonsei UniversitySeoul 03722Korea College of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

We propose a light-weight deep convolutional neural network(CNN)to estimate the cosmological parameters from simulated 3-dimensional dark matter distributions with high *** training set is based on 465 realizations of a cubic box with a side length of 256 h-1 Mpc,sampled with 1283 particles interpolated over a cubic grid of 1283 *** volumes have cosmological parameters varying within the flatΛCDM parameter space of 0.16≤?m≤0.46 and 2.0≤109 As≤*** neural network takes as an input cubes with 32^3 oxels and has three convolution layers,three dense layers,together with some batch normalization and pooling *** the final predictions from the network we find a 2.5%bias on the primordial amplitudeσ8 that cannot easily be resolved by continued *** correct this bias to obtain unprecedented accuracy in the cosmological parameter estimation with statistical uncertainties ofδ?m=0.0015 andδσ8=0.0029,which are several times better than the results of previous CNN *** with a 2-point analysis method using the clustering region of 0-130 and 10-130 h-1 Mpc,the CNN constraints are several times and an order of magnitude more precise,***,we conduct preliminary checks of the error-tolerance abilities of the neural network,and find that it exhibits robustness against smoothing,masking,random noise,global variation,rotation,reflection,and simulation *** effects are well understood in typical clustering analysis,but had not been tested before for the CNN *** work shows that CNN can be more promising than people expected in deriving tight cosmological constraints from the cosmic large scale structure.

关键词： large-scale structure of Universe cosmological parameters dark energy machine learning

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Cardiovascular risk burden and disability:findings from the International Mobility in Aging Study(IMIAS)

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Journal of geriatric Cardiology 2024年第3期21卷 331-339页

作者： Juan-David Martinez-Aristizábal Carmen-Lucia Curcio Juliana Fernandes Afshin Vafael cristiano dos Santos gomes Fernando gomez Internal Medicine Critical Care DepartmentPablo Tobón Uribe HospitalMedellínColombia Research group in geriatrics and gerontology Faculty of Health SciencesUniversidad de CaldasManizalesColombia Laboratory of Physical Therapy and Collective Health Physical Therapy DepartmentFederal University of PernambucoJornalista Aníbal Fernandes Avenue RecifeBrazil Department of Public Health Sciences Queen’s UniversityKingstonONCanada Department of Physiotherapy University of PernambucoBR 203KmBrazil

BACKgROUND The association of cardiovascular risk burden with disability is *** examined the association between trajectories of the Framingham general cardiovascular disease risk score(FgCRS)with the trajectories of limitations of physical function in older *** A total of 1219 participants with no disabilities from the International Mobility in Aging Study(IMIAS)study who had up to three repeated measures of FgCRS between 2012–2016 and without a history of stroke or coronary heart disease at baseline and follow-up were *** at baseline was assessed and categorized into *** function was evaluated with the Short Physical Performance Battery(SPPB).The data were analyzed using linear mixed-effects *** At baseline,FgCRS ranged between 3–94(mean score:24±15.8),participants were 32(2.6%),502(41.2%)and 685(56.2%)in lowest,middle,and highest tertiles,*** the trajectories of limitations of physical function,the lowest FgCRS had no differences,while the middle and highest had a decrease in physical performance between 2012–2014(P=0.0001).Age,being female,living in Andes Mountains,having middle and highest FgCRS,higher alcohol consumption,being obese,lack of exercise and cognitive impairment increase the probability of disability(Pg in more developed regions and having a higher educational level reduced the probability of disability during the follow-up time(Pgher cardiovascular risk burden is associated with decreased physical performance,especially in *** suggest SPPB may provide a measure of cardiovascular health in older adults.

关键词： finding Battery burden

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Determining the effective elastic thickness through cross-correlation between isostatic disturbances

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geodesy and geodynamics 2024年第3期15卷 241-251页

作者： Nelson Ribeiro-Filho cristiano Mendel Martins Raissa Moraes Baldez Ivaldevingles Rodrigues de Souza Júnior Franck Eitel Kemgang ghomsi Instituto Federal do Pará(IFPA) AltamiraParáBrazil Universidade Federal do Pará(UFPA) BelemParáBrazil Nansen-Tutu Center for Marine Environmental Research Department of OceanographyUniversity of Cape TownSouth Africa geodesy Research Laboratory National Institute of CartographyYaoundeCameroon

The elastic thickness parameter was estimated using the mobile correlation technique between the observed isostatic disturbance and the gravity disturbance calculated through direct gravimetric modeling. We computed the vertical flexure value of the crust for a specific elastic thickness using a given topographic dataset. The gravity disturbance due to the topography was determined after the calculation. A grid of values for the elastic thickness parameter was generated. Then, a moving correlation was performed between the observed gravity data(representing actual surface data) and the calculated data from the forward modeling. The optimum elastic thickness of the particular point corresponded to the highest correlation coefficient. The methodology was tested on synthetic data and showed that the synthetic depth closely matched the original depth, including the elastic thickness value. To validate the results, the described procedure was applied to a real dataset from the Barreirinhas Basin, situated in the northeastern region of Brazil. The results show that the obtained crustal depth is highly correlated with the depth from known models. Additionally, we noted that the elastic thickness behaves as expected, decreasing from the continent towards the ocean. Based on the results, this method has the potential to be employed as a direct estimate of crustal depth and elastic thickness for any region.

关键词： Isostasy Elastic thickness Isostatic disturbance Moho depth Cross-correlation

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Assessment of slow deformations and landslide modelling in the urban area through a multi-methodological approach

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Journal of Earth Science 2024年

作者： Fabio Ietto Massimo Conforti cristiano Tolomei Federico Cella giuseppe Cianflone Università degli Studi della Calabria， Dipartimento di Biologia， Ecologia e Scienze della Terra (DiBEST)， Via P.Bucci， Cubo 15B， 87036 Consiglio Nazionale Ricerche (CNR)， Istituto di Ricerca per la Protezione Idrogeologica (IRPI)， Via Cavour INgV-Istituto Nazionale di geofisica e Vulcanologia， Via di Vigna Murata 605 Università di Camerino， Scuola di Scienze e Tecnologia， Sez.geologia， Via gentile III da Varano 27

Slow-moving landslides are widespread in the Mediterranean area， causing damage to the exposed facilities and economic losses in many countries. The recognition of slow-moving landslides in urban areas is always a difficult task to deal with because the presence of buildings， infrastructures， and human activities usually conceals the morphological signs of these landslide activities. So， in the last decades， numerous researchers have shown new methodologies to deepen the studies of similar instability phenomena. The present research is based on an integrated approach to investigate the landslide boundaries， type of movement， failure surface depth， and vulnerability state of buildings in Rota greca village (Calabria region， southern Italy) affected by a slow-moving landslide. For this purpose， multi-source data were acquired through geological and geomorphological surveys， recognition of landslide-induced damage on the built environment， subsurface investigations (e.g.， continuous drill boreholes， Standard Penetration Test， Rock Quality Designation index and inclinometer monitoring)， laboratory tests (direct shear tests on undisturbed samples)， geophysical survey， and InSAR-derived map of deformation rates. The complete integration of multi-source data allowed for the construction of reliable landslide modelling with relative geotechnical properties. In addition， the cross-comparison between surface deformation data by SAR images and severity damage level collected on the exposed buildings enabled to obtain the vulnerability map of the built area. In particular， the achieved goals highlighted two failure surfaces at about -13 and -25 m depth， causing a high vulnerability value for the buildings allocated in the central portion of the Rota greca village. The knowledge acquired by the multi-approach can be used to manage and implement appropriate landslide risk mitigation strategies， providing helpful advice and best practices to state-run organisations and stakeholder

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巴西油气勘探开发历程:从陆上到超深水

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石油勘探与开发 2024年第4期51卷 796-806页

作者： ANJOS Sylvia M C SOMBRA cristiano L SPADINI Adali R 巴西国家石油公司里约热内卢20231-030巴西

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变... 详细信息

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变、重大突破和关键理论技术。巴西国家石油公司(简称巴西国油)自1953年成立以后的15年间,在陆上古生界克拉通盆地和断陷盆地进行了勘探,并于断块和三角洲砂体圈闭获得了一些中小型油气发现。20世纪70年代,应用重力流沉积模式和高质量三维地震等勘探新技术,在坎波斯盆地浅水中发现Namorado和Enchova等油田,随后深水盐上勘探获得突破,成功发现Marlim、Roncador等大型油田。21世纪初,通过盐下含油气系统、碳酸盐岩成储成藏模式和核磁共振测井等理论技术攻关,推动桑托斯盆地下白垩统湖相碳酸盐岩陆续获得Tupi(Lula)、Buzios、Mero等世界级超深水盐下大油田的系列重大发现。在复杂的深水作业环境下,油气开发工程面临巨大挑战,巴西国油通过启动深水研发计划(PROCAP),开发并实施窄压力窗口控压钻井、加压钻井液帽钻井、多段智能完井、水下采油及浮式生产平台开发和流动保障等关键技术,显著提升了钻完井、油气田开发和输运的效率及安全性。此外,在浮式采储卸油系统建产规模受限的情况下,推进全球最大规模的CO_(2)捕集、驱油利用与埋存工程(CCUS-EOR),有效减少温室气体排放并提高了原油采收率。上述理论技术的发展和应用,也为全球深水油气勘探开发提供了宝贵经验。未来巴西油气勘探将继续聚焦深水盐下碳酸盐岩和盐上浊积岩,并在古生界天然气等勘探领域持续寻求新的发现,同时通过技术创新和战略合作,促进巴西石油天然气行业的可持续发展。

关键词：巴西深水盐下勘探坎波斯盆地桑托斯盆地浊积岩湖相碳酸盐岩深水开发流动保障

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Tribologically induced nanostructural evolution of carbon materials: A new perspective

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Friction 2024年第1期12卷 144-163页

作者： guilherme Oliveira NEVES Nicolás ARAYA Diego Berti SALVARO Thiago de Souza LAMIM Renan Oss gIACOMELLI cristiano BINDER Aloisio Nelmo KLEIN JoséDaniel Biasoli de MELLO Laboratório de Materiais Universidade Federal de Santa CatarinaSanta Catarina 88040-900Brazil Departamento de Ingeniería Mecánica Facultad de IngenieríaUniversidad del Bío-BíoConcepcion 4070-386Chile Universidad de Concepción Concepcion 4070-386Chile SENAI Innovation Institute for Laser Processing Santa Catarina 89218-153Brazil Universidade Federal de Uberlândia Minas Gerais 38408-100Brazil

Carbon-based solid lubricants are excellent options to reduce friction and wear,especially with the carbon capability to adopt different allotropes *** the macroscale,these materials are sheared on the contact along with debris and contaminants to form tribolayers that govern the tribosystem *** a recently developed advanced Raman analysis on the tribolayers,it was possible to quantify the contactinduced defects in the crystalline structure of a wide range of allotropes of carbon-based solid lubricants,from graphite and carbide-derived carbon particles to multi-layer graphene and carbon *** addition,these materials were tested under various dry sliding conditions,with different geometries,topographies,and solid-lubricant application *** of the initial tribosystem conditions and allotrope level of atomic ordering,there is a remarkable trend of increasing the point and line defects density until a specific saturation limit in the same order of magnitude for all the materials tested.

关键词： carbon nanostructures tribology Raman spectroscopy defects quantification tribolayer solid lubrication

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Device-assisted enteroscopy: Are we ready to dismiss the spiral?

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World Journal of gastroenterology 2024年第26期30卷 3185-3192页

作者： Alessandro Mussetto Elettra Merola Cesare Casadei Daniele Salvi Fabiola Fornaroli Silvia Cocca Margherita Trebbi Armando gabbrielli cristiano Spada Andrea Michielan Department of gastroenterology S Maria della Croci HospRavenna 48121Italy Department of gastroenterology Unit G.B.Grassi Hospital(ASL Roma 3)Roma 00122Italy Section of Digestive Endoscopy and gastroenterology Fondazione PoliambulanzaBrescia 25124Italy gastroenterology and Endoscopy Unit Department of Medicine and SurgeryUniversity of ParmaParma 43125Italy gastroenterology and Endoscopy Unit Azienda Ospedaliero Universitaria Policlinico di ModenaModena 41121Italy Center for Medical Sciences(CISMed) University of TrentoTrento 38122Italy gastroenterology and Digestive Endoscopy Unit Santa Chiara HospitalAzienda Provinciale per i Servizi SanitariTrento 38122Italy Digestive Endoscopy Unit Fondazione Policlinico Universitario A.Gemelli IRCSSRoma 00168Italy

Motorized spiral enteroscopy(MSE)is the latest advance in device-assisted *** events related to MSE were discussed in a recent large systematic review and meta-analysis and were directly compared with those of balloon enteroscopy in a case-matched study and a randomized controlled *** the real-life application of MSE,an unexpected safety issue emerged regarding esophageal injury and the technique has been withdrawn from the global market,despite encouraging results in terms of diagnostic and therapeutic *** conducted an Italian multicenter real-life prospective study,which was prematurely terminated after the withdrawal of MSE from the *** primary goals were the evaluation of MSE performance(both diagnostic and therapeutic)and its safety in routine endoscopic practice,particularly in the early phase of introduction in the endoscopic unit.A subanalysis,which involved patients who underwent MSE after unsuccessful balloon enteroscopy,demonstrated,for the first time,the promising performance of MSE as a rescue *** its remarkable performance in clinical practice and its potential role as a backup technique following a previously failed enteroscopy,it may be more appropriate to refine and enhance MSE in the future rather than completely abandoning it.

关键词： Motorized spiral enteroscopy Rescue enteroscopy Diagnostic yield Adverse events AgREE classification

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Corrigendum to ‘A novel STK11 gene mutation (c.388dupg,***130glyfs∗33) in a Peutz-Jeghers family and evidence of higher gastric cancer susceptibility associated with alterations in STK11 region aa 107–170’ [gene Dis (9) (2022) 288–291]

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genes & Diseases 2024年第2期11卷 1082-1083页

作者： giovanna Forte Filomena Cariola Katia De Marco Andrea Manghisi Filomena Anna guglielmi Raffaele Armentano giuseppe Lippolis Pietro giorgio cristiano Simone Vittoria Disciglio Medical genetics National Institute of Gastroenterology “S. de Bellis” Research Hospital Castellana Grotte Bari 70013 Italy Histopathology Unit National Institute of Gastroenterology “S. de Bellis” Research Hospital Castellana Grotte Bari 70013 Italy Department of general Surgery National Institute of Gastroenterology “S. de Bellis” Research Hospital Castellana Grotte Bari 70013 Italy gastroenterology and Digestive Endoscopy Unit National Institute of Gastroenterology “S. de Bellis” Research Hospital Castellana Grotte Bari 70013 Italy Department of Biomedical Sciences and Human Oncology (DIMO) Medical Genetics University of Bari Aldo Moro Piazza Umberto I Bari 70124 Italy

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Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

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Effects of frothers on bubbles size and flotation performance of hydrophobic minerals

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Journal of Central South University 2024年第7期31卷 2280-2299页

作者： gülşah gÜVEN Berivan TUNÇ ŞBeste AYDIN gülay BULUT Mineral Processing Engineering Department Faculty of MinesIstanbul Technical UniversityMaslak 34469IstanbulTurkey Research Center Metso OutotecKuparitie 1028101 PoriFinland

Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable *** collision probability of the bubbles and particles substantially increases by decreasing bubble *** the same volume system,fewer bubbles result from a distribution of large-sized bubbles,and more bubbles result from a distribution of small-sized *** this research,fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation *** this purpose,the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol(MIBC),isooctanol(2 ethyl hexanol),pine oil,and Dowfroth *** on the results of single frothers,isooctanol at the lowest critical coalescence concentration(CCC)value of 6×10^(−6) achieved the smallest bubbles with Sauter mean diameter of 0.80 *** blending Dowfroth 250 and pine oil,the bubbles size decreased significantly,reaching 0.45 *** the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system,and such a relationship was not found for talc flotation.

关键词： flotation frother blends bubble size coal and talc flotation

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