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Generic singularities for 2d pressureless flows

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Science China Mathematics 2024年

作者： alberto Bressan Geng Chen Shoujun Huang department of Mathematics Penn State University University Park department of Mathematics University of Kansas College of Mathematical Medicine Zhejiang Normal University

In this paper, we consider the Cauchy problem for pressureless gases in two space dimensions with the generic smooth initial data(density and velocity). These equations give rise to singular curves, where the mass has a positive density with respect to the 1-dimensional Hausdorff measure. We observe that the system of equations describing these singular curves is not hyperbolic. For analytic data, local solutions are constructed by using a version of the Cauchy-Kovalevskaya theorem. We then study the interaction of two singular curves in the generic position. Finally, for a generic initial velocity field, we investigate the asymptotic structure of the smooth solution up to the first time when a singularity is formed.

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Perturbed initial orbit determination

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Astrodynamics 2024年第3期8卷 401-416页

作者： alberto Fossà Matteo Losacco Roberto Armellin Institut Supérieur de l’Aéronautique et de l’Espace Toulouse31400France Te PūnahaĀtea-Space Institute The University of AucklandAuckland1010New Zealand

An algorithm for robust initial orbit determination (IOd) under perturbed orbital dynamics is presented. By leveraging map inversion techniques defined in the algebra of Taylor polynomials, this tool returns a highly accurate solution to the IOd problem and estimates a range centered on the aforementioned solution in which the true orbit should lie. To meet the specified accuracy requirements, automatic domain splitting is used to wrap the IOd routines and ensure that the local truncation error, introduced by a polynomial representation of the state estimate, remains below a predefined threshold. The algorithm is presented for three types of ground-based sensors, namely range radars, doppler-only radars, and optical telescopes, by considering their different constraints in terms of available measurements and sensor noise. Finally, the improvement in performance with respect to a Keplerian-based IOd solution is demonstrated using large-scale numerical simulations over a subset of tracked objects in low Earth orbit.

关键词： initial orbit determination(IOd) range radar doppler radar optical telescope differential algebra(dA)

Molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

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BIOCELL 2024年第6期48卷 897-904页

作者： CARLOS alberto-SILVA BRENdA RUFINO dA SILVA Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-d-aspartate(NMdA)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the Muscarinic acetylcholine receptor subtype M1(mAChR-M1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Identification and functional characterization of fish IL‑17 receptors suggest important roles in the response to nodavirus infection

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Marine Life Science & Technology 2024年第2期6卷 252-265页

作者： Carmen González‑Fernández Miguel A.García‑Álvarez alberto Cuesta department of Cell Biology and Histology Faculty of BiologyUniversity of Murcia30100 MurciaSpain Laboratoire d’écotoxicologie Centre de Lyon-VilleurbanneINRAEUR RiverLy69625 VilleurbanneFrance

Th17 is a lymphocyte T helper(Th)subpopulation relevant in the control and regulation of the immune response characterized by the production of interleukin(IL)-*** crucial cytokine family acts through their binding to the IL-17 receptors(IL-17R),having up to six *** the biology of fish Th17 is well-recognized,the molecular and functional characterization of IL-17 and IL-17R has been ***,our aim was to identify and characterize the IL-17R repertory and regulation in the two main Mediterranean cultured fish species,the gilthead seabream(Sparus aurata)and the European sea bass(dicentrarchus labrax).Our in silico results showed the clear identification of six members in each fish species,from IL-17RA to IL-17RE-like,with well-conserved gene structure and protein domains with their human *** of them showed wide and constitutive transcription in naïve tissues but with highest levels in mucosal tissues,namely skin,gill or *** leucocytes,T mitogens showed the strongest up-regulation in most of the il17 receptors though il17ra resulted in inhibition by most ***,in vivo nodavirus infection resulted in alterations on the transcription of il17 *** nodavirus infection led to some increments in the il17ra,il17rb,il17rc and il17rd transcripts in the susceptible European sea bass,many down-regulations were observed in the resistant gilthead *** data identify the presence and conservation of six coding IL-17R in gilthead seabream and European sea bass as well as their differential regulation in vitro and upon nodavirus infection.

关键词： Th17 cells IL-17 receptors Immunity Teleost fish Nodavirus(NNV) Aquaculture

Advances in two-dimensional molybdenum ditelluride(MoTe2):A comprehensive review of properties,preparation methods,and applications

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SusMat 2024年第5期4卷 31-69页

作者： Pratik V.Shinde Muzammil Hussain Elisa Moretti alberto Vomiero department of Molecular Sciences and Nanosystems Ca’Foscari University of VeniceVeneziaItaly department of Industrial Engineering University of PadovaPadovaItaly department of Engineering Sciences and Mathematics Lulea University of TechnologyLuleaSweden

In the past decade,molybdenum ditelluride(MoTe2)has received significant attention from the scientific community due to its structural features and unique properties originate from *** the current review,the properties,various preparation approaches,and versatile applications of MoTe2 are *** review provides a brief update on the state of our fundamental understanding of MoTe2 material and also discusses the issues that need to be *** introduce MoTe2,we briefly summarize its structural,optoelectronic,magnetic,and mechanical properties in the ***,different preparation meth-ods of MoTe2,such as exfoliation,laser treatment,deposition,hydrothermal,microwave,and molecular beam epitaxy,are *** excellent electri-cal conductivity,strong optical activity,tunable bandgap,high sensitivity,and impressive stability make it an ideal contender for different applications,includ-ing energy storage,catalysis,sensors,solar cells,photodetectors,and *** performance of MoTe2 in these applications is systematically introduced along with mechanistic *** the end of the article,the challenges and possible future directions are highlighted to further modify MoTe2 material for the numerous ***,the availability of different phases and layer structures implies a potential for MoTe2 to lead an era of two-dimensional materials that began from the exfoliation of graphene.

关键词： 2d materials MoTe2 (opto)electronic devices phase structure and bandgap tuning

Coke behavior with H_(2)O in a hydrogen-enriched blast furnace:A review

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 959-976页

作者： Feng Zhou daosheng Peng Kejiang Li alberto N.Conejo Haotian Liao Zixin Xiong dongtao Li Jianliang Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering The University of QueenslandSt LuciaQLD 4072Australia Baosteel Central Research Institute(R&d Center of Wuhan Iron&Steel Co. Ltd.)Wuhan 430080China Shougang Research Institute of Technology Shougang Group Corporation Ltd.Beijing 100043China Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology Beijing 100043China

Hydrogen-enriched blast furnace ironmaking has become an essential route to reduce CO_(2)emissions in the ironmaking ***,hydrogen-enriched reduction produces large amounts of H_(2)O,which places new demands on coke quality in a blast *** a hydrogen-rich blast furnace,the presence of H_(2)O promotes the solution loss *** result improves the reactivity of coke,which is 20%-30%higher in a pure H_(2)O atmosphere than in a pure CO_(2)*** activation energy range is 110-300 kJ/mol between coke and CO_(2)and 80-170 kJ/mol between coke and H_(2)***_(2)and H_(2)O are shown to have different effects on coke degradation *** review provides a comprehensive overview of the effect of H_(2)O on the structure and properties of *** exploring the interactions between H_(2)O and coke,several unresolved issues in the field requiring further research were *** review aims to provide valuable insights into coke behavior in hydrogen-rich environments and promote the further development of hydrogen-rich blast furnace ironmaking processes.

关键词： hydrogen ironmaking coke behavior blast furnace gasification microstructure kinetics

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BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-López M.Pérez-Labra J.A.romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.dávila-Pulido Academic Area of Earth Sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRd） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 doping Europium Gadolinium Rare earths Synthesis

Advancing Wound Filling Extraction on 3d Faces:An Auto-Segmentation and Wound Face Regeneration Approach

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2197-2214页

作者： duong Q.Nguyen Thinh d.Le Phuong d.Nguyen Nga T.K.Le H.Nguyen-Xuan department of Mathematics and Statistics Quy Nhon UniversityQuy Nhon City55100Viet Nam Applied Research Institute for Science and Technology Quy Nhon UniversityQuy Nhon City55100Viet Nam CIRTECH Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical *** this paper,we propose an efficient approach for automating 3d facial wound segmentation using a two-stream graph convolutional *** method leverages the Cir3d-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss *** achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the *** selectedmodel demonstrates exceptional segmentation performance for complex 3d facial ***,based on the segmentation model,we propose an improved approach for extracting 3d facial wound fillers and compare it to the results of the previous *** method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous *** this result,we use 3d printing technology to illustrate the shape of the wound *** outcomes of this study have significant implications for physicians involved in preoperative planning and intervention *** automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient ***,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3d bioprinting for printing skin tissue *** source code is available at https://***/SIMOGroup/WoundFilling3d.

关键词： 3d printing technology face reconstruction 3d segmentation 3d printed model

A Tutorial on Federated Learning from Theory to Practice:Foundations,Software Frameworks,Exemplary Use Cases,and Selected Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 824-850页

作者： M.Victoria Luzón Nuria Rodríguez-Barroso alberto Argente-Garrido daniel Jiménez-López Jose M.Moyano Javier del Ser Weiping ding Francisco Herrera department of Software Engineering Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain department of Computer Science and Artificial Intelligence Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain department of Communications Engineering University of the Basque Country(UPV/EHU)and also with TECNALIABasque Research&Technology Alliance(BRTA)Spain School of Information Science and Technology Nantong UniversityNantong 226019China

When data privacy is imposed as a necessity,Federated learning(FL)emerges as a relevant artificial intelligence field for developing machine learning(ML)models in a distributed and decentralized *** allows ML models to be trained on local devices without any need for centralized data transfer,thereby reducing both the exposure of sensitive data and the possibility of data interception by malicious third *** paradigm has gained momentum in the last few years,spurred by the plethora of real-world applications that have leveraged its ability to improve the efficiency of distributed learning and to accommodate numerous participants with their data *** virtue of FL,models can be learned from all such distributed data sources while preserving data *** aim of this paper is to provide a practical tutorial on FL,including a short methodology and a systematic analysis of existing software ***,our tutorial provides exemplary cases of study from three complementary perspectives:i)Foundations of FL,describing the main components of FL,from key elements to FL categories;ii)Implementation guidelines and exemplary cases of study,by systematically examining the functionalities provided by existing software frameworks for FL deployment,devising a methodology to design a FL scenario,and providing exemplary cases of study with source code for different ML approaches;and iii)Trends,shortly reviewing a non-exhaustive list of research directions that are under active investigation in the current FL *** ultimate purpose of this work is to establish itself as a referential work for researchers,developers,and data scientists willing to explore the capabilities of FL in practical applications.

关键词： data privacy distributed machine learning federated learning software frameworks

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