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Groups Whose Proper Subgroups of Infinite Rank Have Polycyclic Conjugacy Classes

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Algebra Colloquium 2015年第2期22卷 181-188页

作者： francesco de giovanni Marco Trombetti Dipartimento di Matematica e Applicazioni Universita di Napoli Federico II Complesso Universitario Monte S. Angelo Via Cintia I- 80126 Napoli Italy

A group G is called a PC-group if the factor group G/CG（〈X）^G） is polycyclic for each element x of G. It is proved here that if G is a group of infinite rank whose proper subgroups of infinite rank have the property PC, then G itself is a PC-group, provided that G has an abelian non-trivial homomorphic image. Moreover, under the same assumption, a complete classification of minimal non-PC groups is obtained.

关键词： PC-group minimal non-PC group group of infinite rank

A new three-dimensional finite-volume non-hydrostatic shock-capturing model for free surface flow

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Journal of Hydrodynamics 2017年第4期29卷 552-566页

作者： francesco Gallerano giovanni Cannata francesco Lasaponara Chiara Petrelli department of Civil Constructional and Environmental Engineering Sapienza University of Rome

In this paper a new finite-volume non-hydrostatic and shock-capturing three-dimensional model for the simulation of wave-structure interaction and hydrodynamic phenomena（wave refraction, diffraction, shoaling and breaking） is proposed. The model is based on an integral formulation of the Navier-Stokes equations which are solved on a time dependent coordinate system： a coordinate transformation maps the varying coordinates in the physical domain to a uniform transformed space. The equations of motion are discretized by means of a finite-volume shock-capturing numerical procedure based on high order WENO reconstructions. The solution procedure for the equations of motion uses a third order accurate Runge-Kutta（SSPRK） fractional-step method and applies a pressure corrector formulation in order to obtain a divergence-free velocity field at each stage. The proposed model is validated against several benchmark test cases.

关键词： Three-dimensional simulation non-hydrostatic wave-structure interaction flow-structure interaction shock-capturing

Involvement of interleukin-15 and interleukin-21, two γ-chain-related cytokines, in celiac disease

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World Journal of Gastroenterology 2009年第37期15卷 4609-4614页

作者： Daniela de Nitto Ivan Monteleone Eleonora Franzè francesco Pallone giovanni Monteleone department of Internal Medicine University of Rome "Tor Vergata" 00133 Rome Italy

Celiac disease (CD), an enteropathy caused by dietary gluten in genetically susceptible individuals, is histologically characterized by villous atrophy, crypt cell hyperplasia, and increased number of intra-epithelial lymphocytes. The nature of CD pathogenesis remains unclear, but recent evidence indicates that both innate and adaptive immune responses are necessary for the phenotypic expression and pathologic changes characteristic of CD. Extensive studies of molecules produced by immune cells in the gut of CD patients have led to identification of two cytokines, namely interleukin (IL)-15 and IL-21, which are thought to play a major role in orchestrating the mucosal inflammatory response in CD. Here we review the current knowledge of the expression and function of IL-15 and IL-21 in CD.

关键词： Interleukin-21 Interleukin-15 Celiac disease

Irritable bowel syndrome and food interaction

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World Journal of Gastroenterology 2014年第27期20卷 8837-8845页

作者： Rosario Cuomo Paolo reozzi francesco Paolo Zito Valentina Passananti giovanni de Carlo giovanni Sarnelli department Of Clinical Medicine and Surgery Federico Ⅱ University Hospital School of Medicine

Irritable bowel syndrome(IBS) is one of the most common gastrointestinal disorders in Western countries. despite the high prevalence of this disorders, the therapeutic management of these patients is often unsatisfactory. A number of factors have been suggested to be involved in the pathogenesis of IBS, including impaired motility and sensitivity, increased permeability, changes in the gut microbiome and alterations in the brain-gut axis. Also food seems to play a critical role: the most of IBS patients report the onset or the exacerbation of their symptoms after the meals. Recently, an increasing attention has been paid to the role of food in IBS. In this review we summarize the most recent evidences about the role of diet on IBS symptoms. A diet restricted in fermentable, poorly absorbed carbohydrates and sugar alcohols has beneficial effects on IBS symptoms. More studies are needed to improve our knowledge about the relationship between food and IBS. However, in the foreseeable future, dietary strategies will represent one of the key tools in the therapeutic management of patients with IBS.

关键词： Irritable bowel syndrome Fermentable,poorly absorbed carbohydrates and sugar alcohols Gut microbiota Food intolerance Gluten

Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： giovanni Ricci Anna Sommazzi francesco Masi Alessandra Forni CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and *** some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction *** the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar *** behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

designs andmethodologies to recreate in vitro human gutmicrobiota models

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Bio-design and Manufacturing 2023年第3期6卷 298-318页

作者： francesco Biagini Costanza Daddi Marco Calvigioni Carmelo de Maria Yu Shrike Zhang Emilia Ghelardi giovanni Vozzi Research Center(E.Piaggio) University of PisaPisaItaly department of Information Engineering University of PisaPisaItaly department of Translational Research and New Technologies in Medicine and Surgery University of PisaPisaItaly Division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMAUSA

The human gut microbiota is widely considered to be a metabolic organ hidden within our bodies,playing a crucial role in the host’s *** factors affect its composition,so a wide variety of microbes residing in the gut are present in the world *** excessive imbalances in microbial composition are often associated with human disorders and pathologies,and new investigative strategies to gain insight into these pathologies and define pharmaceutical therapies for their treatment are *** vitro models of the human gut microbiota are commonly used to study microbial fermentation patterns,community composition,and host-microbe *** and microfluidic devices have been designed to culture microorganisms from the human gut microbiota in a dynamic environment in the presence or absence of eukaryotic cells to interact *** this review,we will describe the overall elements required to create a functioning,reproducible,and accurate in vitro culture of the human gut *** addition,we will analyze some of the devices currently used to study fermentation processes and relationships between the human gut microbiota and host eukaryotic cells.

关键词： Gut microbiota In vitro models Bioreactors Host-microbiome Fermentation

Modulation of the magnetic properties of gold-spinel ferrite heterostructured nanocrystals

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Nano Research 2020年第3期13卷 785-794页

作者： Elvira Fantechi Claudia Innocenti giovanni Bertoni Claudio Sangregorio francesco Pineider INSTM and dept of Chemistry and Industrial ChemistryUniversity of PisaPisa 56124Italy ICCOM-CNR Institute for the Chemistry of OrganoMetallic CompoundsSesto Fiorentino 50019Italy INSTM and dept of Chemistry aU.Schiffnt University of FlorenceSesto Fiorentino 50019Italy IMEM-CNR Institute of Materials for Electronics and MagnetismParma 43124Italy CNR-Istituto Nanoscienze Modena 41125Italy

The rational design of complex nanostructures is of paramount importance to gain control over their chemical and physical ***,magnetic-plasmonic heterostructured nanocrystals have been recognized as key players in nanomedicine as multifunctional therapeutic-diagnostic tools and in *** we show how the properties of gold-iron oxide heterostructured nanocrystals can be tuned by chemical doping of the magnetic *** divalent cations in the iron oxide were substituted with cobalt and manganese to obtain a general formula Au-MFe2O4(M=Fe,Co,Mn).Magnetic properties of the heterostructures could be tuned,while maintaining well-defined plasmon resonance signatures,confirming the dual magnetic-plasmonic functional capability of these nanostructures.

关键词： heterostructured nanocrystals seeded-growth spinel ferrites magnetic-plasmonic nanoparticles

Isoxazolone Reactivity Explained by Computed Electronic Structure Analysis

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Chinese Journal of Chemistry 2020年第2期38卷 163-168页

作者： giovanni Bella Antonio Santoro Massimiliano Cordaro francesco Nicolò Giuseppe Bruno department of Chemical BiologicalPharmaceutical and Environmental SciencesUniversity of MessinaViale F.Stagno d'Alcontres 3198166 MessinaItaly

Summary of main observation and conclusion lsoxazol(2H)-5-one was chosen as a model molecule to study the structural features(a,p angles and carbonyl bond length)regarding lactone moiety in the isoxazolone species by computational *** method with B3LYP 6-311++G(2df,2p)basis set was used to carry out the optimization on a series(A and B families)of isoxazolones suitably substituted on double bond.

关键词： calculation. moiety substituted

The onset of the tetrabonded structure in liquid water

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 51-59页

作者： Carla Andreani Carmelo Corsaro Domenico Mallamace giovanni Romanelli Roberto Senesi francesco Mallamace Dipartimento di Fisica and NAST Center Universita degli Studi di Roma Tor VergataRome 00133Italy CNR-IPCF Istituto peri Processi Chimico-Fisici del CNR di MessinaMessina 98158Italy Dipartimento MIFT Universita di MessinaMessina 98166Italy ISIS Facility Rutherford Appleton LaboratoryChiltonDidcotOxfordshire OX11 0QXUK Istituto dei Sistemi Complessi(ISC)-CNR Rome 00185Italy Center for Polymer Studies and department of Physics Boston UniversityBoston 02215USA

Water properties are dominated by the hydrogen bond interaction that gives rise in the stable liquid phase to the formation of a dynamical *** latter drives the water thermodynamics and is at the origin of its well known *** HB structural geometry and its changes remain uncertain and still are challenging research subjects.A key question is the role and effects of the HB tetrahedral structure on the local arrangement of neighboring molecules in *** the hydrogen dynamics in bulk water is studied through the combined use of Neutron Compton Scattering and NMR *** are discussed in the framework of previous studies performed in a wide temperature range,in the liquid,solid,and amorphous *** the first time this combined studies provide an experimental evidence of the onset of the water tetrahedral network at T^315 K,originally proposed in previous studies of transport coefficients and thermodynamical data;below this temperature the local order in water changes and the lifetime of local hydrogen bond network becomes long enough to gradually develop the characteristic tetrahedral network of water.

关键词： water neutron compton scattering NMR