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Pancreas-preserving segmental duodenectomy for gastrointestinal stromal tumor of the duodenum and splenectomy for splenic angiosarcoma

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Hepatobiliary & Pancreatic Diseases International 2012年第3期11卷 325-329页

作者： mirko muroni Matteo Ravaioli Massimo Del Gaudio Giuseppe Nigri Francesco D'Angelo Stefania Uccini Giovanni Ramacciato Division of Hepato-Biliary-Pancreatic Surgery Department of General Surgery La Sapienza University of Rome Second School of Medicine St. Andrea Hospital Division of Hepato-Biliary-Pancreatic Surgery Department of General Surgery and Department of Clinical and Molecular Medicine La Sapienza University of Rome Second School of Medicine St. Andrea Hospital

BACKGROUND: Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract and occur rarely in the duodenum. Splenic angiosarcoma is an aggressive neoplasm with an extremely poor prognosis. METHODS: We report a case of a 70-year-old man hospitalized for abdominal pain in the upper quadrants, dyspepsia and nausea, previously treated for Hodgkin lymphoma 30 years ago. Abdominal CT showed a solid nodular lesion in the third portion of the duodenum, the presence of retropancreatic, aortic and caval lymph nodes, and four nodular splenic masses. 111 In-octreotide scintigraphy revealed pathological tissue accumulation in the duodenal region, and in the retropancreatic, retroduodenal, aortic and caval lymph nodes, suggesting a nonfunctioning neuroendocrine peripancreatic tumor. RESULTS: At exploratory laparotomy, an exophytic soft tumor was found originating from the third portion of the duodenum. Pancreas-preserving duodenectomy with duodenojejunostomy, splenectomy and lymphnodectomy of retropancreatic aortic and caval lymph nodes were performed. Pathological evaluation and immunohistochemical studies showed the presence of a duodenal gastrointestinal stromal tumor with low mitotic activity and a well-differentiated angiosarcoma localized to the spleen and invading lymph ***: We speculated that the angiosarcoma and duodenal gastrointestinal stromal tumors of this patient were due to the treatment of Hodgkin lymphoma with radiotherapy 30 years ago. Pancreas-preserving segmental duodenectomy can be used to treat non-malignant neoplasms of the duodenum and avoid extensive surgery. Splenectomy is the treatment of choice for localized angiosarcomas but a strict follow-up is mandatory because of the possibility of recurrence.

关键词： duodenal neoplasms gastrointestinal stromal tumors hemangiosarcoma splenectomy splenic neoplasms pancreaticoduodenectomy

Immunity of electronic and transport properties of phosphorene nanoribbons to edge defects

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Nano Research 2016年第6期9卷 1723-1734页

作者： mirko Poljak Tomislav Suligoj Micro and Nano Electronics Laboratory Faculty of Electrical Engineering and Computing University of Zagreb Unska 3 HR-10000Zagreb Croatia

We present an extensive study of the electronic properties and carrier transport in phosphorene nanoribbons （PNRs） with edge defects by using rigorous atomistic quantum transport simulations. This study reports on the size- and defect-dependent scaling laws governing the transport gap, and the mean free path and carrier mobility in the PNRs of interest for future nanoelectronics applications. Our results indicate that PNRs with armchair edges （aPNRs） are more immune to defects than zig-zag PNRs （zPNRs）, while both PNR types exhibit superior immunity to defects relative to graphene nanoribbons （GNRs）. An investigation of the mean free path demonstrated that even in the case of a low defect density the transport in PNRs is diffusive, and the carrier mobility remains a meaningful transport parameter even in ultra-small PNRs. We found that the electron-hole mobility asymmetry （present in large-area phosphorene） is retained only in zPNRs for W 〉 4 nrn, while in other cases the asymmetry is smoothed out by edge defect scattering. Furthermore, we showed that aPNRs outperform both zPNRs and GNRs in terms of carrier mobility, and that PNRs generally offer a superior mobility-bandgap trade-off, relative to GNRs and monolayer MoS2. This work identifies PNRs as a promising material for the extremely scaled transistor channels in future posbsilicon electronic technology, and presents a persuasive argument for experimental work on nanostructured phosphorene.

关键词： phosphorene nanoribbons atomistic quantumtransport simulation edge defects transport gap mean free path electron and hole mobility

Long time data series and data stewardship reference model

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Big Earth Data 2020年第4期4卷 353-366页

作者： mirko Albani Iolanda Maggio European Space Agency Frascati RomaItaly Rhea Group WavreBelgium

The need for accessing historical Earth Observation(EO)data series strongly increased in the last ten years,particularly for long-term science and environmental monitoring *** trend is likely to increase even more in the future,in particular regarding the growing interest on global change monitoring which is driving users to request time-series of data spanning 20 years and more,and also due to the need to support the United Nations Framework Convention on Climate Change(UNFCCC).While much of the satellite observations are accessible from different data centers,the solution for analyzing measurements collected from various instruments for time series analysis is both difficult and *** research is a big data problem that involves high data volume of measurements,methods for on-the-fly extraction and reduction to keep up with the speed and data volume,and the ability to address uncertainties from data collections,processing,and *** content of EO data archives is extending from a few years to decades and therefore,their value as a scientific time-series is continuously *** there is a strong need to preserve the EO space data without time constraints and to keep them accessible and *** preservation of EO space data can also be considered as responsibility of the Space Agencies or data owners as they constitute a humankind *** publication aims at describing the activities supported by the European Space Agency relating to the Long Time Series generation with all relevant best practices and models needed to organise and measure the preservation and stewardship *** Data Stewardship Reference Model has been defined to give an overview and a way to help the data owners and space agencies in order to preserve and curate the space datasets to be ready for long time data series composition and analysis.

关键词： Heritage Data Programme long time data series fundamental climate data record long-term data preservation

Nonlinear analysis of r.c. framed buildings retrofitted with elastomeric and friction bearings under near-fault earthquakes

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Earthquake Science 2015年第5期28卷 365-377页

作者： mirko Mazza Dipartimento di Ingegneria Civile Universita della CalabriaPonte Bucci

Reinforced concrete （r.c.） framed buildings designed in compliance with inadequate seismic classifi- cations and code provisions present in many cases a high vulnerability and need to be retrofitted. To this end, the insertion of a base isolation system allows a considerable reduction of the seismic loads transmitted to the super- structure. However, strong near-fault ground motions, which are characterised by long-duration horizontal pulses, may amplify the inelastic response of the superstructure and induce a failure of the isolation system. The above considerations point out the importance of checking the effectiveness of different isolation systems for retrofitting a r.c. framed structure. For this purpose, a numerical inves- tigation is carried out with reference to a six-storey r.c. framed building, which, primarily designed （as to be a fixed-base one） in compliance with the previous Italian code （DM96） for a medium-risk seismic zone, has to be retrofitted by insertion of an isolation system at the base for attaining performance levels imposed by the current Italian code （NTC08） in a high-risk seismic zone. Besides the （fixed-base） original structure, three cases of base isolation are studied： elastomeric bearings acting alone （e.g. HDLRBs）; in-parallel combination of elastomeric and friction bearings （e.g. high-damping-laminated-rubber beatings, HDLRBs and steel-PTFE sliding bearings, SBs）; friction bearings acting alone （e.g. friction pendulum bearings, FPBs）. The nonlinear analysis of the fixed-base and base-isolated structures subjected to horizontal com- ponents of near-fault ground motions is performed for checking plastic conditions at the potential critical （end） sections of the girders and columns as well as critical conditions of the isolation systems. Unexpected high val- ues of ductility demand are highlighted at the lower floors of all base-isolated structures, while re-centring problems of the base isolation systems under near-fault earthquakes a

关键词： R.c. base-isolated structures Elastomericbearings Friction bearings Nonlinear dynamic analysis

Effects of near-fault ground motions on the nonlinear behaviour of reinforced concrete framed buildings

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Earthquake Science 2015年第4期28卷 285-302页

作者： mirko Mazza Dipartimento di Ingegneria Civile Università della CalabriaArcavacata di Rende

The design provisions of current seismic codes are generally not very accurate for assessing effects of near-fault ground motions on reinforced concrete （r.c.） spatial frames, because only far-fault ground motions are considered in the seismic codes. Strong near-fault earth- quakes are characterized by long-duration （horizontal） pulses and high values of the ratio ~PGA of the peak value of the vertical acceleration, PGAv, to the analogous value of the horizontal acceleration, PGAH, which can become critical for girders and columns. In this work, six- and twelve-storey r.c. spatial frames are designed according to the provisions of the Italian seismic code, considering the horizontal seismic loads acting （besides the gravity loads） alone or in combination with the vertical ones. The non- linear seismic analysis of the test structures is performed using a step-by-step procedure based on a two-parameter implicit integration scheme and an initial stress-like itera- tive procedure. A lumped plasticity model based on the Haar-K^n~m principle is adopted to model the inelastic behaviour of the frame members. For the numerical investigation, five near-fault ground motions with high values of the acceleration ratio C^p6A are considered. Moreover, following recent seismological studies, which allow the extraction of the largest （horizontal） pulse from a near-fault ground motion, five pulse-type （horizontal） ground motions are selected by comparing the original ground motion with the residual motion after the pulse has been extracted. The results of the nonlinear dynamic analysis carried out on the test structures highlighted thathorizontal and vertical components of near-fault ground motions may require additional consideration in the seis- mic codes.

关键词： Near-fault ground motions Nonlineardynamic analysis r.c. spatial frames

Fluorine-containing oxidizers for metal fuels in energetic formulations

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Defence Technology（防务技术） 2019年第1期15卷 1-22页

作者： Siva Kumar Valluri mirko Schoenitz Edward Dreizin New Jersey Institute of Technology Tomsk State University

Fluorine containing oxidizers, primarily polymers, are extensively used in pyrotechnic *** oxidizers are less explored for metalized propellants and explosives despite a potential advantage of substantial heat release combined with gaseous combustion products. This review summarizes different types of fluorinated oxidizers used in energetic formulations or of potential interest for such systems, including gases, polymers, and inorganic compounds. Types of energetic formulations employing metals and fluoropolymers are discussed in more detail, including methods used to prepare composites and resulting salient features of the obtained materials. Laboratory experiments characterizing such materials, in particular, electron microscopy and thermal analysis, are discussed, showing characteristic morphologies and reaction sequences observed in different metal-fluorinated oxidizer composites. Striking similarities are noted in reaction sequences for diverse compositions hinting at possible similarities in the respective reaction mechanisms. Experiments probing ignition and combustion of metal-fluorinated oxidizer composites in laboratory conditions are also reviewed, including impact, flash heating and shock ignition. Finally, some practical performance tests for energetic formulations are described following by a brief discussion of the reaction mechanisms expected to govern ignition and combustion in various metal-fluorinated oxidizer composites. The conclusions are combined with recommendation for future research in the area of reactive metal-fluorinated oxidizer composites.

关键词： Reactive materials Composites Redox reactions Pyrotechnics Propellants Explosives

Vapor-phase decomposition of dimethyl methylphosphonate (DMMP),a sarin surrogate,in presence of metal oxides

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Defence Technology（防务技术） 2021年第4期17卷 1095-1114页

作者： Shomik Mukhopadhyay mirko Schoenitz Edward L.Dreizin New Jersey Institute of Technology NewarkNJUSA

Chemical warfare agents(CWA)are stockpiled in large quantities across the *** stored in inaccessible facilities need to be destroyed rapidly without dispersing the compounds to surrounding ***-based energetic formulations are used in such prompt defeat applications to rapidly decompose the CWA by generating a high temperature *** alternate,and possibly a more effective decomposition pathway could be provided by chemicidal action of aerosolized condensed combustion products,which typically consist of metal *** fumes that escape the high temperature blast zone can be neutralized by smoke generated during combustion,depending on the particle size,surface characteristics,chemical properties,and concentration of this *** review considers relevant experimental and modeling studies quantifying decomposition of CWA comprising organophosphorus compounds and their surrogates on the surface of various metal *** methylphosphonate(DMMP),a sarine surrogate,was used most commonly for such *** reported efforts focused on the mechanisms of adsorption of DMMP to various metal oxides and initial reaction steps cleaving various bonds from the chemisorbed *** selected oxides,these experiments were supported by quantum-mechanical *** other studies,the capacity of oxide surfaces to adsorb and decompose DMMP was *** most cases,porous catalysts were used although limited experimental data are available for aerosolized nonporous oxide *** reported experimental data applicable to scenarios involving prompt decomposition of CWA are *** is noted that information is lacking describing respective heterogeneous reaction *** estimates of aerosolized smoke particle concentrations required to destroy CWA are made considering gas phase diffusion rates and reported values of the oxide capacity to decompose CWA or their surrogates.

关键词： Chemical weapon agents Prompt defeat Metal combustion Heterogeneous reactions

A review on membrane distillation in process engineering: design and exergy equations, materials and wetting problems

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Frontiers of Chemical Science and Engineering 2022年第5期16卷 592-613页

作者： Stefano Capizzano mirko Frappa Francesca Macedonio Enrico Drioli Institute of Membrane Technology National Research Council of ItalyRende 87036Italy Department of Environmental Engineering University of CalabriaRendeItaly Nanjing Tech University College of Chemical EngineeringNanjing 211816China

One of the problems that most afflicts humanity is the lack of clean *** stress,which is the pressure on the quantity and quality of water resources,exists in many places throughout the *** represents a valid solution to the scarcity of fresh water and several technologies are already well applied and successful(such as reverse osmosis),producing about 100 million m^(3)·d^(-1) of fresh *** advances in the field of desalination can be provided by innovative processes such as membrane *** latter is of particular interest for the treatment of waste currents from conventional desalination processes(for example the retentate of reverse osmosis)as it allows to desalt highly concentrated currents as it is not limited by concentration polarization *** perspectives have enhanced research activities and allowed a deeper understanding of mass and heat transport phenomena,membrane wetting,polarization phenomena and have encouraged the use of materials particularly suitable for membrane distillation *** work summarizes recent developments in the field of membrane distillation,studies for module length optimization,commercial membrane modules developed,recent patents and advancement of membrane material.

关键词： membrane distillation recent developments heat and mass transfer wetting membrane material

Ray tracing particle image velocimetry-Challenges in the application to a packed bed

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Particuology 2024年第1期84卷 194-208页

作者： Christin Velten mirko Ebert Christian Lessig Katharina Zahringer Lehrstuhl für Strömungsmechanik und Strömungstechnik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany Institut für Simulation und Graphik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany

Ray tracing Particle Image Velocimetry(RT-PIV)is an optical technique for high resolution velocity measurements in challenging optical systems,such as transparent packed beds,that uses ray tracing to correct for distortions introduced by transparent geometries in the light *** ray tracing based correction is a post processing step applied to the raw PIV particle images before classical PIV *** this study,RT-PIV is performed in the top layer of a body centred cubic(bcc)sphere packing with gaseous flow,where optical access is obtained by the use of transparent N-BK7 glass balls with a diameter of d=40 ***-PIV introduces new experimental and numerical challenges,for example a limited field of view,illumination difficulties,a very large required depth of field and high sensitivity to geometric parameters used in the ray tracing *** challenges and their implications are the main scope and discussed in the present ***,the validation of the ray tracing reconstruction step is presented and examples for the obtained corrected vector fields in a packed bed are *** results show the strength of the method in reconstructing velocity fields behind transparent spheres that would not have been accessible by optical measurement techniques without the ray tracing correction.

关键词： Ray tracing particle image velocimetry(RT-PIV) Transparent spherical particles Packed bed Distortion correction Gas flow