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International Journal of Smart and Nano Materials 2014年第1期5卷 59-74页

作者： Sara Filippi giovanni Polacco Department of Civil and Industrial Engineering University of PisaLargo Lucio Lazzarino156126 PisaItaly

Ethylene copolymers with different polar comonomers,such as vinyl acetate,methyl acrylate,glycidyl methacrylate,and maleic anhydride,were used for the preparation of polymer/clay nanocomposites by statically annealing their mechanical mixtures with different commercial or home-made organically modified montmorillonites containing only one long alkyl *** nanostructure of the products was monitored by X-ray diffraction,and the dispersion of the silicate particles within the polymer matrix was qualitatively evaluated through microscopic *** effect of the preparation conditions on the structure and the morphology of the composites was also addressed through the characterization of selected samples with similar composition prepared by melt *** agreement with the findings reported in a previous paper for the composites filled with two-tailed organoclays,intercalation of the copolymer chains within the tighter galleries of the one-tailed clays occurs easily,independent of the application of a mechanical ***,the shear-driven break-up of the intercalated clay particles into smaller platelets(exfoliation)seems more hindered.A collapse of the organoclay interlayer spacing was only observed clearly for a commercial one-tailed organoclay-Cloisite®30B–whereas the same effect was almost negligible for a home-made organoclay with similar structure.

关键词： ethylene copolymers one-tailed organoclays annealing X-ray diffraction

Central Schemes and Second Order Boundary Conditions for 1D Interface and Piston Problems in Lagrangian Coordinates

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Communications in Computational Physics 2010年第9期8卷 797-822页

作者： Riccardo Fazio giovanni Russo Department of Mathematics University of MessinaSalita Sperone 3198166 MessinaItaly Department of Mathematics and Computer Science University of CataniaViale Andrea Doria 695125 CataniaItaly

We study high-resolution central schemes in Lagrangian coordinates for the one-dimensional system of conservation laws describing the evolution of two gases in slab geometry separated by an *** using Lagrangian coordinates,the interface is transformed to a fixed coordinate in the computational domain and,as a consequence,the movement of the interface is obtained as a byproduct of the numerical *** main contribution is the derivation of a special equation of state to be imposed at the interface in order to avoid non-physical *** boundary conditions at the piston that guarantee second order convergence are *** compare the solution of the piston problem to other results available in the literature and to a reference solution obtained within the adiabatic approximation.A shock-interface interaction problem is also *** results on these tests are in good agreement with those obtained by other methods.

关键词： Lagrangian central schemes Euler equations interface conditions boundary conditions

Endoscopic papillectomy: Indications, techniques, and results

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World Journal of Gastroenterology 2014年第6期20卷 1537-1543页

作者： giovanni D De Palma Center of Excellence for Technical Innovation in Surgery Department of Clinical Medicine and Surgery University of Naples Federico Ⅱ School of Medicine

Endoscopic papillectomy (EP) is currently accepted as a viable alternative therapy to surgery in sporadic ampullary adenoma and has been reported to have high success and low recurrence rates. At present, the indications for EP are not yet fully established. The accepted criteria for EP include size (up to 5 cm), no evidence of intraductal growth, and no evidence of malignancy on endoscopic findings (ulceration, friability, and spontaneous bleeding). Endoscopic ultrasound (EUS) is the imaging modality of choice for local T staging in ampullary neoplasms. Data reported in the literature have revealed that linear EUS is superior to helical computed tomography in the preoperative assessment of tumor size, detection of regional nodal metastases and detection of major vascular invasion. Endoscopic ampullectomy is performed using a standard duodenoscope in a similar manner to snare polypectomy of a mucosal lesion. There is no standardization of the equipment or technique and broad EP methods are described. Endoscopic ampullectomy is considered a ‘‘high-risk’’ procedure due to complications. Complications of endoscopic papillectomy can be classified as early (pancreatitis, bleeding, perforation, and cholangitis) and late (papillary stenosis) complications. The appropriate use of stenting after ampullectomy may prevent post-procedural pancreatitis and papillary stenosis. Tumor recurrence of benign lesions occurs in up to 20% of patients and depends on tumor size, final histology, presence of intraductal tumor, coexisting familial adenomatous polyposis (FAP), and the expertise of the endoscopist. Recurrent lesions are usually benign and most can be retreated endoscopically.

关键词： Endoscopic papillectomy Papillary neoplasms Major duodenal papilla Endoscopic retrograde cholangiopancreatography Endoscopic sphincterotomy

Down-regulation of DPH2L gene during cellular differentiation/apoptosis:Use of mRNA differential display

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Chinese Science Bulletin 1999年第6期44卷 496-503页

作者： Nicoletta Ferrari giovanni Levi Laboratory of Molecular Biology National Institute for Cancer ResearchLaboratory of Molecular Biology National Institute for Cancer Research Genova Italy Genova Italy

To characterize the genes associated with differentiation/apoptosis induced by all-trans retinoic acid (ATRA) in human lung cancer cells, mRNA differential display was employed. Six cDNA fragments have been isolated, and one of them corresponds to a sequence-known gene DPH2L with unknown function, which was first isolated from the critical region of deletion on chromosome 17p13.3 in human ovarian carcinoma, and regarded as a candidate tumor suppressor gene. Results show that DPH2L is a wide expressed gene, and has another major transcript besides the previously reported 2.3 kb transcript. It is proved that the DPH2L gene is dawn-regulated during differentiation or apoptosis in several kinds of cancer cells induced by all-trans retinoic acid and N-(4-hydroxyphenyl) retinamide (4HPR). This may suggest that DPH2L does not play a role as a tumor suppressor gene, on the contrary, its down-regulation may be functionally involved in the transition from cell growth to differentiation or apoptosis.

关键词： mRNA differential display retinoic acids cell differentiation apoptosis tumor suppressor gene.

NPV risk simulation of an open pit gold mine project under the O'Hara cost model by using Gas

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International Journal of Mining Science and Technology 2017年第3期27卷 557-565页

作者： Franco-Sepulveda giovanni Campuzano Carlos Pineda Cindy Department of Materials and Minerals National University of Colombia Medellin 050036 Colombia

This paper analyzes an open pit gold mine project based on the O'Hara cost model. Hypothetical data is proposed based on different authors that have studied open pit gold projects, and variations are proposed according to the probability distributions associated to key variables affecting the NPV, like production level, ore grade, price of ore, and others, so as to see what if, in a gold open pit mine project of 3000 metric tons per day of ore. Two case scenarios were analyzed to simulate the NPV, one where there is low certainty data available, and the other where the information available is of high certainty. Results based on genetic algorithm metaheuristic simulations, which combine basically Montecarlo simulations provided by the Palisade Risk software, the O'Hara cost model, net smelter return and financial analysis tools offered by Excel are reported, in order to determine to which variables of the project is more sensitive the NPV.

关键词： Genetic algorithms(GAs) O’Hara cost model Montecarlo simulation Open pit gold mine NPV risk analysis

3D Identification of Face and Flank in Micro-mills for Automatic Measurement of Rake Angle

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Nanomanufacturing and Metrology 2020年第2期3卷 151-163页

作者： Stefano Petro giovanni Moroni Department of Mechanical Engineering Politecnico di MilanoVia Giuseppe la Masa 120156 MilanItaly

In an Industry 4.0 context,to each object a"digital twin"is associated,which is a virtual counterpart of the object *** the case of a tool,this includes,together with its material and manufacturing information,its solid *** geometry knowledge is fundamental to enable effective tool management,manufacturing verification,and tooling *** for tool management the conventional 2D presetting is sufficient,tooling simulation and tool manufacturing verification require a complete 3D *** is particularly true in the case of the microtools:the process of micro-chip formation is still a research *** the 3D geometry of a tool is well established in the ISO 3002 series of standard,only recently 3D measurement of tools has been made possible by new measuring ***,tool geometry verification requires a lot of human *** paper aims at setting the base for the automatic analysis of point meshes scanned on the whole surface of tools,and in particular *** first step for doing this is the identification of the active surfaces of the tool,that is the face and the flank plus the cutting *** identification of these geometric features is in general possible thanks to their specific characteristics:in particular,the cutting edge is characterized by a high curvature,and it separates the face from the *** paper considers cylindrical micro end-mills as a first example of an approach that can be extended to in principle any kind of *** cylindrical helix characterizing the cutting edge is the key geometry to be considered in the development of the specific *** the tool features(face,flank,and cutting edge)have been separated,of the tool angles,for instance,can be *** first angle to study,the rake angle has been *** approach will be validated on simulated data and on real scans of micro-tools.

关键词： Tool metrology 3D measurement Partitioning Tool angles

Together We Stand-Analyzing Schooling Behavior in Naive Newborn Guppies through Biorobotic Predators

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Journal of Bionic Engineering 2020年第1期17卷 174-184页

作者： Donato Romano Hadeel Elayan giovanni Benelli Cesare Stefanini The BioRobotics Institute Sant'Anna School of Advanced StudiesPontederaPisa 56025Italy Healthcare Engineering Innovation Center(HEIC) Khalifa UniversityAbu DhabiPO Box 127788United Arab Emirates Department of Excellence in Robotics&A.I. Sant'Anna School of Advanced StudiesPisa 56127Italy Department of Electrical and Computer Engineering University of TorontoON M5SCanada Department of Agriculture Food and EnvironmentUniversity of PisaPisa 56124Italy

A major advantage of animal aggregations concerns cooperative antipredator *** behavior emerges earlier in many fish species,especially in those cannibalizing their *** is fundamental for developing schooling ***,the cognitive ability of naive newborn fish to aggregate remains ***,Poecilia reticulata,was selected as model organism to investigate how combinations of biomimetic robotic agents and adult conspecific olfactory cues affect collective responses in *** role of white and brown backgrounds in evoking aggregations was also *** cues were sufficient for triggering aggregations in *** newborns,although robotic agents had a higher influence on the group *** combination of robotic agents and olfactory cues increased schooling behavior ***,schooling was longer in the escape compartment when robotic agents were presented,except for the combination of the male-mimicking robotic fish plus adult guppy olfactory cues,with longer schooling behavior in the exploring *** of the tested cues,newborn fish aggregated preferentially on the brown areas of the ***,this research provides novel insights on the early collective cognitive ability of newborn fish,paving the way to the use of biomimetic robots in behavioral ecology experiments,as substitutes for real predators.

关键词： animal-robot interaction technology bio-hybrid intelligent systems antipredator strategy group behavior Poecilia reticulata

Second Order Multigrid Methods for Elliptic Problems with Discontinuous Coefficients on an Arbitrary Interface, I: One Dimensional Problems

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Numerical Mathematics(Theory,Methods and Applications) 2012年第1期5卷 19-42页

作者： Armando Coco giovanni Russo Dipartimento di Matematica e Informatica Universitàdi CataniaViale Andrea Doria695125CataniaItaly

In this paper we present a one dimensional second order accurate method to solve Elliptic equations with discontinuous coefficients on an arbitrary *** order accuracy for the first derivative is obtained as *** method is based on the Ghost Fluid Method,making use of ghost points on which the value is defined by suitable interface *** multi-domain formulation is adopted,where the problem is split in two sub-problems and interface conditions will be enforced to close the *** conditions are relaxed together with the internal equations(following the approach proposed in[10]in the case of smooth coefficients),leading to an iterative method on all the set of grid values(inside points and ghost points).A multigrid approach with a suitable definition of the restriction operator is *** restriction of the defect is performed separately for both sub-problems,providing a convergence factor close to the one measured in the case of smooth coefficient and independent on the magnitude of the jump in the *** tests will confirm the second order *** the method is proposed in one dimension,the extension in higher dimension is currently underway[12]and it will be carried out by combining the discretization of[10]with the multigrid approach of[11]for Elliptic problems with non-eliminated boundary conditions in arbitrary domain.

关键词： Elliptic equation discontinuous coefficient second order accuracy multigrid arbitrary interface jump conditions

Could metabolic syndrome lead to hepatocarcinoma via non-alcoholic fatty liver disease?

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World Journal of Gastroenterology 2014年第28期20卷 9217-9228页

作者： Antonella Scalerar giovanni Tarantino Department of Clinical Medicine and Surgery Federico Ⅱ University Medical School of Naples National Cancer Institute "Pascale Foundation"IRCS

It was estimated that from 2002 to 2008 the risk of developing cancer increased a quarter-fold in men and two-fold in women due to excessive BMI. Obesity, metabolic syndrome and type 2 diabetes mellitus are strictly related and are key pathogenetic factors of non-alcoholic fatty liver disease (NAFLD), the most frequent liver disease worldwide. The most important consequence of the “metabolic epidemics” is the probable rise in the incidence of hepatocarcinoma (HCC), and NAFLD is the major causative factor. Adipose tissue is not merely a storage organ where lipids are preserved as an energy source. It is an active organ with important endocrine, paracrine, and autocrine actions in addition to immune functions. Adipocytes produce a wide range of hormones, cytokines, and growth factors that can act locally in the adipose tissue microenvironment and systemically. In this article, the main roles of insulin growth factor (IGF)-1 and IGF-2 are discussed. The role of IGF-2 is not only confined to HCC, but it may also act in early hepato-carcinogenesis, as pre-neoplastic lesions express IGF-2 mRNA. IGF-1 and IGF-2 interact with specific receptors (IGF-1R and IGF-2R). IGF-1R is over-expressed in in vitro and in animal models of HCC and it was demonstrated that IGF ligands exerted their effects on HCC cells through IGF-1R and that it was involved in the degeneration of pre-neoplastic lesions via an increase in their mitotic activity. Both IGF-2R and TGF β, a growth inhibitor, levels are reduced in human HCC compared with adjacent normal liver tissues. Another key mechanism involves peroxisome proliferator-activated receptor (PPAR)γ. In in vitro studies, PPARγ inhibited various carcinomas including HCC, most probably by regulating apoptosis via the p21, p53 and p27 pathways. Finally, as a clinical consequence, to improve survival, efforts to achieve a “healthier diet” should be promoted by physicians and politicians.

关键词： Hepatocarcinoma Non-alcoholic fatty liver disease Insulin growth factor Peroxisome proliferatoractivated receptor γ Adipokines

Locally-advanced prostate cancer in the elderly： should we revisit our treatment paradigms？

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Asian Journal of Andrology 2015年第5期17卷 769-770页

作者： giovanni Lughezzani Nicolo Maria Buffi Department of Urology Istituto Clinico HumanitasRozzano Italy

Prostate cancer （PCa） represents the most common malignancy in adult males with an estimated number of 280 000 newly diagnosed cases only in the United States in 2015. Due to the introduction of PSA in clinical practice, the majority of the patients are currently diagnosed with organ-confined and sometimes indolent disease. However, a nonnegligible proportion of individuals are still diagnosed with locally-advanced tumors. In their recently published article, Bekelman et al. focused on elderly patients with locally-advanced PCa in the attempt to determine the best treatment approach in this patient category, and concluded that, even in these individuals, androgen deprivation therapy （ADT） plus radiotherapy （RT） may confer a survival benefit relative to ADT alone. The importance of the current article resides in the fact that it focuses on a patient population that has not been, or has been only scarcely, included in previous studies on the same topic.

关键词： patient Prostate determine