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A Semi-Lagrangian Spectral Method for the Vlasov-Poisson System Based on Fourier, Legendre and Hermite Polynomials

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Communications on Applied Mathematics and Computation 2019年第3期1卷 333-360页

作者： Lorella Fatone daniele Funaro Gianmarco Manzini Dipartimento di Matematica University degli Studi di CamerinoCamerinoItaly Dipartimento di Scienze Chimiche e Geologiche Universita degli Studi di Modena e Reggio EmiliaModenaItaly Group T-5 Applied Mathematics and Plasma PhysicsTheoretical DivisionLos Alamos National LaboratoryLos AlamosNMUSA

In this work, we apply a semi-Lagrangian spectral method for the Vlasov-Poisson system, previously designed for periodic Fourier discretizations, by implementing Legendre polynomials and Hermite functions in the approximation of the distribution function with respect to the velocity variable. We discuss second-order accurate-in-time schemes, obtained by coupling spectral techniques in the space-velocity domain with a BDF timestepping scheme. The resulting method possesses good conservation properties, which have been assessed by a series of numerical tests conducted on some standard benchmark problems including the two-stream instability and the Landau damping test cases. In the Hermite case, we also investigate the numerical behavior in dependence of a scaling parameter in the Gaussian weight. Confirming previous results from the literature, our experiments for different representative values of this parameter, indicate that a proper choice may significantly impact on accuracy, thus suggesting that suitable strategies should be developed to automatically update the parameter during the time-advancing procedure.

关键词： Spectral methods Semi-Lagrangian methods High-order Hermite functions Vlasov-Poisson equations Mass conservation

On the origin of plasticity-induced microstructure change under sliding contacts

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Friction 2023年第3期11卷 473-488页

作者： Yilun XU Daniel S.BALINT Christian GREINER daniele DINI Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Materials Imperial College LondonLondon SW72AZUK Karlsruhe Institute of Technology(KIT) Institue for Applied Materials(IAM)Kaisertrasse 12Karlsruhe 76131Germany KITIAM-CMS MicroTribology Center(μTC) Strasse am Forum 5Karlsruhe 76131Germany

Discrete dislocation plasticity(DDP)calculations are carried out to investigate the response of a single crystal contacted by a rigid sinusoidal asperity under sliding loading conditions to look for causes of microstructure change in the dislocation *** mechanistic driver is identified as the development of lattice rotations and stored energy in the subsurface,which can be quantitatively correlated to recent tribological experimental *** of surface slip initiation and substrate permanent deformation obtained from DDP calculations for varying contact size and normal load suggest ways of optimally tailoring the interface and microstructural material properties for various frictional loads.

关键词： discrete dislocation plasticity sliding size effect microstructure change

Enhancer-promoter communication:unraveling enhancer strength and positioning within a given topologically associating domain(TAD)

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Signal Transduction and Targeted Therapy 2022年第9期7卷 3161-3162页

作者： Benedetto daniele Giaimo Tilman Borggrefe Institute of Biochemistry Justus-Liebig-University GiessenFriedrichstrasse 2435392 GiessenGermany

In a recent study published in Nature,Zuin et *** the molecular mechanisms of how enhancer positioning and strength affect gene expression levels.'Cell-type-specific transcription factors(TFs)and ubiquitously expressed cofactors regulate the complex network of eukar-yotic gene transcription in an exquisitely specific and sensitive *** DNA elements bound by TFs are called enhancers and can be located close to the transcription start site(TSS)or far away.

关键词： al. strength topological

Bjorken Flow Revisited:Analytic and Numerical Solutions in Flat Space-Time Coordinates

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Communications in Computational Physics 2023年第1期33卷 174-188页

作者： daniele Simeoni Alessandro Gabbana Sauro Succi Universit`a di Ferrara and INFN-Ferrara I-44122 FerraraItaly Bergische UniversitatWuppertal D-42119WuppertalGermany University of Cyprus Physics departmentCY-1678 NicosiaCyprus Eindhoven University of Technology 5600MB EindhovenThe Netherlands Center for Life Nano Science@La Sapienza Italian Institute of TechnologyViale Regina Elena 295I-00161 RomaItaly Istituto Applicazioni del Calcolo National Research Council of ItalyVia dei Taurini 19I-00185 RomaItaly

In this work we provide analytic and numerical solutions for the Bjorken flow,a standard benchmark in relativistic hydrodynamics providing a simple model for the bulk evolution of matter created in collisions between heavy *** consider relativistic gases of both massive and massless particles,working in a(2+1)and(3+1)Minkowski space-time coordinate *** numerical results from a recently developed lattice kinetic scheme show excellent agreement with the analytic solutions.

关键词： Relativistic hydrodynamics heavy-ion collisions Bjorken flow lattice kinetic solvers

Measuring and understanding global human settlements patterns and processes:innovation,progress and application

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International Journal of Digital Earth 2020年第1期13卷 2-8页

作者： Ehrlich daniele Balk Deborah Richard Sliuzas 不详

Human settlements–the places where people live and work–are rapidly *** of the processes driving the physical changes in human settlements are population and economic growth,rural-urban migration,and in-situ urban transformation that also includes the envelopment of small settlements by larger ones and land-expansive *** some parts of the world,particularly the global South,urbanization occurs at rates that generate unprecedented city sizes(WUP 2018).

关键词： settlement development sizes

Shape Controllable Preparation of Submicronic Cadmium Tetrazole-Based Metal-Organic Frameworks via Solvothermal or Microwave-Assisted Methods and Their Photocatalytic Studies

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Chinese Journal of Chemistry 2017年第2期35卷 209-216页

作者： Arti Chouhan Guillaume Pilet Stephane daniele Ashutosh Pandey Department of Chemistry MNNIT Allahabad Allahabad 211004 India LMI UMR CNRS 5615 University Claude Bernard-Lyon 1 69622 Villeurbanne cedex France IRCELYON UMR CNRS 5256 University Claude Bernard-Lyon 1 69626 Villeurbanne cedex France

The paper describes the experiments conducted to create shape controllable preparations of submicronic cad- mium tetrazole-based MOFs. In order to prepare the submicron sized blocks and tubes of bis[5-（2-pyridyltetrazo- lato）]diaquacadmium（II） [（2-PTZ）2Cd（H20）2] MOFs both solvothermal and microwave augmented reaction proce- dures have been followed. Cadmium nitrate tetrahydrate, cyanopyridine and sodium azide were used as reactants in both the conditions without any surfactants or modulators. Subsequently, IR spectroscopy and single-crystal X-ray crystallographic studies were performed on the prepared MOFs. Examinations using scanning electron microscopy and X-ray powder diffraction of the products made by the microwave method showed formation of bundles of reg- ular submicrotubes, as opposed to the submicron-sized irregular blocks of the Cd-MOF obtained through the sol- vothermal method. The fluorescence peak of the sub-microtube MOF was found at 460 nm while the irregu- lar-blocks emitted at 442 nm indicating a red shift for the former. In addition, the relative intensity of the peak at 460 nm was higher in the former, indicating a decrease in the crystallite size. Band gaps of the MOFs calculated by using the Tauc plots were 2.87 and 2.73 eV, respectively. Their photocatalytic performances using methylene blue under UV-vis irradiation have been investigated.

关键词： cadmium microwave synthesis solvothermal synthesis submicrotube photocatalysis

New challenges of geriatric cardiology： from clinical to preclinical research

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Journal of Geriatric Cardiology 2017年第4期14卷 223-232页

作者： Marco Malavolta daniele Caraceni Fabiola Olivieri Roberto Antonicelli Advanced Technology Center for Aging Research Scientific Technological Area IRCCS-INRCA Ancona Italy Department of Clinical and Molecular Sciences DISCLIMO Universit~ Politecnica delle Marche Ancona Italy Center of Clinical Pathology and Innovative Therapy INRCA Ancona Italy Department of Cardiology INRCA-IRCCS National Institute Ancona Italy

The field of geriatric cardiology reflects the evolving medical approaches tailored to address the needs of the growing population of oldest old with cardiovascular diseases （CVD）. The burden of CVD is expected to increase particularly for the most common types of chronic heart disease of the elderly including coronary artery disease, heart failure and atrial fibrillation. In this context of dramatic demographic changes, geriatric cardiologists are facing important challenges. In this review, we outline the basic concepts of geriatric cardiology and describe these challenges as well as the unmet needs around this discipline with also a focus on the translation from basic research.

关键词： Aging Cardiovascular Diseases Geriatric Cardiology Senescence

Assessing and Improving Flood and Landslide Community Social Awareness and Engagement via a Web Platform:The Case of Italy

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International Journal of Disaster Risk Science 2018年第4期9卷 530-540页

作者： daniele F.Bignami Alessio Dragoni Giovanni Menduni Project Development Department Fondazione Politecnico di Milano20133 MilanItaly SciamLab S.r.l 00193 RomeItaly Civil and Environmental Engineering Department Politecnico di Milano20133 MilanItaly

Italy is significantly affected by ever-present flood and landslide risks and has experienced many disasters. Local social awareness and engagement, however,differ and need to be increased by decision makers and citizens through improvements in risk preparedness. With this aim, the #italiasicura web platform was developed by Fondazione Politecnico di Milano and released in 2015 to show country to local level hazard maps and risk reduction projects in Italy. Any stage of the user experience with the platform can be shared via social media. Using this tool, an awareness-oriented web analytics process was structured to develop a set of indicators for the increase of knowledge linked to flood and landslide hazards. In so doing, it is possible to measure community disaster awareness actions and competence in the area of hazard knowledge. This article presents the results obtained by using data from the platform.

关键词： Community disaster risk awareness Disaster risk reduction Hazard knowledge indicators Italy Risk reduction Web platform

A geologically-based approach to map arsenic risk in crystalline aquifers:Analysis of the Tampere region, Finland

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Geoscience Frontiers 2019年第5期10卷 1731-1741页

作者： daniele Pedretti Samrit Luoma Timo Ruskeeniemi Birgitta Backman Geological Survey of Finland (GTK) EspooFinland Dipartimento di Scienze della Terra “A. Desio” Università degli Studi di MilanoMilanItaly

The study illustrates the critical role of accurate geological structural mapping to delineate crystalline aquifer zones more prone to high health risk due to elevated dissolved As in drinking *** analysis revisits the results from more than 1200 groundwater samples collected over ten years from domestic wells across the Tampere region (Finland).It is demonstrated that the highest dissolved As concentrations in the region (up to 2230 mg/L) are exclusively found near major faults and deformation zones (FDZs) detected via geophysical and geological surveys,and that a clear correlation exists between dissolved concentrations and the distance from the FDZs (r).Almost all values exceeding the drinking water limit (10 mg/L) occur at r < 8 km,while concentrations above 100 mg/L occur at r < 4 *** As concentrations in bedrock show less dependency on FDZ than aqueous *** behavior is explained considering different mechanisms,which include enhanced sulfide oxidation and fracture connectivity,promoting preferential transport of dissolved As to FDZs and mixing of waters from different redox zones,mobilizing preferentially As(III) or As(V).Fe hydro-oxides may also precipitate/ dissolve preferentially because of FDZs,while residence time may influence the contact time between water and As-bearing *** is concluded that the accurate mapping of FDZs,and in general of structural geology,provides an important preliminary information to identify where localized,sitespecific characterization of hydrogeology and geochemistry is more urgent to reduce As-related health risk from groundwater intake.

关键词： Arsenic risk Crystalline bedrock Fractured aquifers Heterogeneity Finland