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Efficient GW calculations in two dimensional materials through a stochastic integration of the screened potential

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npj Computational Materials 2023年第1期9卷 1912-1919页

作者： Alberto Guandalini Pino D’Amico andrea Ferretti Daniele Varsano S3 Centre Istituto NanoscienzeCNRVia Campi 213/aModenaItaly Present address:Dipartimento di Fisica Universitàdi Roma La SapienzaPiazzale Aldo Moro 5I-00185 RomaItaly

Many-body perturbation theory methods,such as the G0W0 approximation,are able to accurately predict quasiparticle(QP)properties of several classes of ***,the calculation of the QP band structure of two-dimensional(2D)semiconductors is known to require a very dense BZ sampling,due to the sharp q-dependence of the dielectric matrix in the long-wavelength limit(q→0).In this work,we show how the convergence of the QP corrections of 2D semiconductors with respect to the BZ sampling can be drastically improved,by combining a Monte Carlo integration with an interpolation scheme able to represent the screened potential between the calculated grid *** method has been validated by computing the band gap of three different prototype monolayer materials:a transition metal dichalcogenide(MoS2),a wide band gap insulator(hBN)and an anisotropic semiconductor(phosphorene).The proposed scheme shows that the convergence of the gap for these three materials up to 50meV is achieved by using k-point grids comparable to those needed by DFT calculations,while keeping the grid uniform.

关键词： materials integration potential

Molecular phylogenetic analysis of Leibnitzia Cass.(Asteraceae:Mutisieae:Gerbera-complex),an Asian-North American disjunct genus

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Journal of Systematics and Evolution 2010年第3期48卷 161-174页

作者： Kristen E.BAIRD Vicki A.FUNK andrea WEEKS Department of Environmental Science and Policy George Mason University US National Herbarium Smithsonian InstitutionMRC 166P.O.Box 371012WashingtonDC 20013-7012USA

Leibnitzia comprises six species of perennial herbs that are adapted to high elevation conditions and is one of only two Asteraceae genera known to have an exclusively disjunct distribution spanning central to eastern Asia and North *** phylogenetic analysis of Leibnitzia and other Gerbera-complex members indicates that Leibnitzia is monophyletic,which is in contrast with our expectation that the American Leibnitzia species L. lyrata and *** would be more closely related to another American member of the Gerbera-complex,namely *** area reconstructions show that the historical biogeography of the Gerbera-complex mirrors that of the entire Asteraceae,with early diverging lineages located in South America that were followed by transfers to Africa and Eurasia and,most recently,to North *** transfer of Leibnitzia appears to have been directed from Asia to North *** calibrations of nuclear(ribosomal DNA internal transcribed spacer region)and chloroplast(trnL-rpl32 intron)DNA sequence data using relaxed clock methods and either mean rate or fossil-based priors unanimously support Miocene and younger divergence times for Gerbera-complex *** ages are not consistent with most Gondwanan vicariance episodes and,thus,the global distribution of Gerbera-complex members must be explained in large part by long-distance *** species of Leibnitzia are estimated to have diverged from their Asian ancestor during the Quaternary(ca.2 mya)and either migrated overland to North America via Beringia and retreated southwards along high elevation corridors to their present location in southwestern North America or were dispersed long distance.

关键词： Beringia biogeography Gerbera-complex Mutisieae.

Diagenetic signatures in the deltaic and fluvial-estuarine Messinian sandstone reservoirs in the Nile Delta as a tool for high-resolution stratigraphic correlations

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International Journal of Sediment Research 2023年第5期38卷 754-768页

作者： Mahmoud Leila andrea Moscariello Dustin Sweet Branimir ?egvi? Geology Department Faculty of Science Mansoura University Department of Earth Sciences University of Geneva Department of Geosciences Texas Tech University

The current study utilizes a range of diagenetic fingerprints to differentiate between sandstone facies deposited in the Nile Delta before and during the Messinian salinity crisis(MSC), which is normally a challenging task considering the complex bio-and lithostratigraphic subdivisions of Messinian rock units. Subaerial exposure of the pre-MSC(Qawasim deltaic sandstone), during drawdown of the Mediterranean Sea at the time of the MSC, triggered pervasive dissolution of unstable rock fragments, kaolinization of feldspar, and meteoric dolomitization of carbonate. This was followed by mesogenetic calcite cementation and kaolinite transformation into dickite in deeply buried Qawasim sandstone. Comparatively, the Abu Madi estuarine facies, deposited during transgression after drawdown related to the MSC,is characterized by eogenetic iron(Fe)-calcite, glauconite, and pyrite(averages of 14.5%, 6%, and 2%,respectively). This facies transition is marked by abundance of mature glauconite(with potassium oxide(K2O) at about 8%) whose content abates upward from the transgression surface. Moreover, the compositional variability of the Abu Madi sandstone gave rise to multiple diagenetic trajectories that resulted in chlorite formation presumably following smectite and kaolinite. Listed diagenetic variations in the studied Messinian sandstone resulted from a complex interplay between rocks’ compositional,depositional, and burial attributes, ultimately serving as a basis for high-resolution stratigraphic correlation in continental and marginal marine settings with poor biostratigraphic controls.

关键词： Messinian Nile Delta Diagenesis Deltaic sedimentation Fluvial-estuarine Stratigraphic correlation

Unscrambling light-automatically undoing strong mixing between modes

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Light(Science & Applications) 2017年第1期6卷 342-351页

作者： andrea Annoni Emanuele Guglielmi Marco Carminati Giorgio Ferrari Marco Sampietro David AB Miller andrea Melloni Francesco Morichetti Dipartimento di Elettronica Informazione e BioingegneriaPolitecnico di MilanoMilano 20133Italy Ginzton Laboratory Stanford UniversitySpilker BuildingStanfordCA 94305USA

Propagation of light beams through scattering or multimode systems may lead to the randomization of the spatial coherence of the *** information is not lost,its recovery requires a coherent interferometric reconstruction of the original signals,which have been scrambled into the modes of the scattering *** we show that we can automatically unscramble optical beams that have been arbitrarily mixed in a multimode waveguide,undoing the scattering and mixing between the spatial modes through a mesh of silicon photonics tuneable beam *** light detectors integrated in a photonic chip are used to directly monitor the evolution of each mode along the mesh,allowing sequential tuning and adaptive individual feedback control of each beam *** entire mesh self-configures automatically through a progressive tuning algorithm and resets itself after significantly perturbing the mixing,without turning off the *** demonstrate information recovery by the simultaneous unscrambling,sorting and tracking of four mixed modes,with residual cross-talk of−20 dB between the *** partitioning assisted by transparent detectors enables scalability to meshes with a higher port count and to a higher number of modes without a proportionate increase in the control *** principle of self-configuring and self-resetting in optical systems should be applicable in a wide range of optical applications.

关键词： optical processing photonic integrated circuits silicon photonics tuneable photonic devices

Extracorporeal veno-venous ultrafiltration in congestive heart failure:What’s the state of the art?A mini-review

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World Journal of Cardiology 2023年第5期15卷 205-216页

作者： andrea Urbani Filippo Pensotti andrea Provera andrea Galassi Marco Guazzi Diego Castini Cardiology Unit Department of Health SciencesSan Paolo HospitalUniversity of MilanMilan 20142Italy Nephrology Unit Department of Health SciencesSan Paolo HospitalUniversity of MilanMilan 20142Italy

Hospitalizations for heart failure exceed 1 million per year in both the United States and Europe and more than 90%are due to symptoms and signs of fluid *** of rehospitalizations or emergency department visit at 60 days are remarkable regardless of whether loop diuretics were administered at low vs high doses or by bolus injection vs continuous ***(UF)has been considered a promising alternative to stepped diuretic therapy and it consists in the mechanical,adjustable removal of iso-tonic plasma water across a semipermeable membrane with the application of hydrostatic pressure gradient generated by a *** removal with ultrafiltration presents several advantages such as elimination of higher amount of sodium with less neurohormonal ***,the conflicting results from UF studies highlight that patient selection and fluid removal targets are not completely *** best way to assess fluid status and therefore establish the fluid removal target is also still a matter of ***,we provide an up-to-date systematic review about the role of ultrafiltration among patients with fluid overload and its gaps in daily practice.

关键词： Fluid overload Ultrafiltration Diuretics Heart failure

Marine propellers performance and flow-field prediction by a free-wake panel method

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Journal of Hydrodynamics 2014年第5期26卷 780-795页

作者： GRECO Luca MUSCARI Roberto TESTA Claudio DI MASCIO andrea CNR-INSEAN Italian Ship Model BasinRomeItaly CNR-IAC Istituto per le Applicazioni del Calcolo "M. Picone"RomeItaly

A Boundary Element Method （BEM） hydrodynamics combined with a flow-alignment technique to evaluate blades shed vorticity is presented and applied to a marine propeller in open water. Potentialities and drawbacks of this approach in capturing propeller performance, slipstream velocities, blade pressure distribution and pressure disturbance in the flow-field are highlighted by comparisons with available experiments and RANSE results. In particular, correlations between the shape of the convected vortex- sheet and the accuracy of BEM results are discussed throughout the paper. To this aim, the analysis of propeller thrust and torque is the starting point towards a detailed discussion on the capability of a 3-D free-wake BEM hydrodynamic approach to describe the local features of the flow-field behind the propeller disk, in view of applications to propulsive configurations where the shed wake plays a dominant role.

关键词： BEM hydrodynamics free-wake analysis BEM-RANSE comparison

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Metasurfaces for next-generation wireless communication systems

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National Science Review 2023年第8期10卷 17-19页

作者： Younes Ra'di Nikita Nefedkin Petar Popovski andrea Alù Department of Electrical Engineering and Computer Science Syracuse University Photonics Initiative Advanced Science Research Center City University of New York Department of Electronic Systems Aalborg University Physics Program Graduate Center City University of New York

The pace of development in the world of 5G communication systems has proven to be much more demanding than previous generations, with 5G-Advanced seemingly around the corner [1]. Extensive research is already underway to structure the next generation of wireless systems(i.e. 6G), which may potentially enable an unprecedented level of human–machine interaction [2].

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Analysis of 3.4 Ah lithium-sulfur pouch cells by electrochemical impedance spectroscopy

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Journal of Energy Chemistry 2022年第9期31卷 318-325,I0009页

作者： Dominika Capkova Vaclav Knap andrea Strakova Fedorkova Daniel-Ioan Stroe Department of Physical Chemistry Pavol Jozef Safarik University in KosiceKosice 04154Slovak Republic Faculty of Electrical Engineering Czech Technical University in PraguePrague 16627Czech Republic Department of Energy Technology Aalborg UniversityAalborg East 9220Denmark

Despite great progress in lithium-sulfur(Li-S) batteries, the electrochemical reactions in the cell are not yet fully understood. Electrode processes, complex interfaces and internal resistance may be characterized by electrochemical impedance spectroscopy(EIS). EIS is a non-destructive technique and easy to apply, though there are challenges in ensuring the reproducibility of measurements and the interpretation of impedance data. Here, we present the impedance behavior of a 3.4 Ah Li-S pouch cell characterized by EIS. The impedance changes were analyzed over the entire depth-of-discharge, depth-of-charge,and at various temperatures. Based on the formation of intermediates during(dis)charging, the changes of resistances are observed. Overall, the increase in temperature causes a decrease in electrolyte viscosity,lowering the surface energy which can improve the penetration of the electrolyte into the electrode pores. Moreover, the effect of superimposed AC current during EIS measurement was analyzed, and the results show the dependence of the charge transfer resistance on superimposed AC current which was lower compared to steady-state conditions and consents with theory.

关键词： Lithium-sulfur battery Impedance Equivalent circuit Temperature dependencies Charging/discharging differences Dynamic electrochemical impedance spectroscopy

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Multimodal treatment of hepatocellular carcinoma on cirrhosis: An update

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World Journal of Gastroenterology 2013年第42期19卷 7316-7326页

作者： Marco Vivarelli Roberto Montalti andrea Risaliti Hepatobiliary and Abdominal Transplantation Surgery Department of Gastroenterology and TransplantationPolytechnic University of Marche60129 AnconaItaly Department of Surgery and Transplantation University of Udine33100 UdineItaly

Hepatocellular carcinoma(HCC)is the most frequent primary liver tumor,and overall,it is one of the most frequent *** association of HCC with chronic liver disease,and cirrhosis in particular,is well known,making treatment complex and *** treatment of HCC must take into account the presence and stage of chronic liver disease,with the aim of preserving hepatic function that is often already impaired,the stage of HCC and the clinical condition of the *** different treatment options include surgical resection,transplantation,local ablation,chemoembolization,radioembolization and molecular targeted therapies;these treatments can be combined in various ways to achieve different ***,liver transplantation is best treatment for early stage HCC on cirrhosis because it removes both the tumor and the chronic disease that produced it;however,the application of this powerful tool is limited by the scarcity of *** and bridging are different strategies for the management of HCC patients who will undergo liver *** professionals,including gastroenterologists,radiologists and surgeons,are involved in the choice of the most appropriate treatment for a single case,and a multidisciplinary approach is necessary to optimize the *** purpose of this review is to provide a comprehensive description of the current treatment options for patients with HCC by analyzing the advantages,disadvantages and rationale for their use.

关键词： Hepatocellular carcinoma Multimodal treatment Locoregional treatments Molecular targeted therapies Liver resection Liver transplantation