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Summary of Italian marine stages of the Quaternary

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Episodes 2008年第2期31卷 251-254页

作者： Maria Bianca Cita Universita di Milano Dipartimento di Scienze della Terra ＂Ardito Desio＂via Mangiagalli 34 20133 Milano Italy.

Eight marine stages for the Quaternary have been defined in Italy starting from 1872 （Sicilian of Doderlein） to 1979 （Selinuntian of Ruggieri and Sprovieri）. The definition of all these stages was based essentially on invertebrate paleontology, initially from the study of pelecypods and gastropods, but also of corals, ostracods, benthic foraminifers and, more recently, on planktonic foraminifers and calcareous nannofossils. The 1948 International Geological Congress held in London decided to search for a locality in Italy to define the Neogene/Quaternary boundary in correspondence with the first appearance of the ＂northern guests＂ in the Mediterranean. The Vrica section of Calabria was selected for defining the GSSP of the Pleistocene in 1984.

关键词：地球第四纪地质时代意大利航海业

Synthesis of Fine Chemicals by the Conjugate Addition of Nitroalkanes to Electrophilic Alkenes

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复旦学报（自然科学版） 2005年第5期44卷 629-630页

作者： R. Ballini G. Bosica D. Fiorini A. Palmieri dipartimento di scienze Chimiche dell'Università di Camerino Via S. Agostino 1 62032 Camerino ItalyDipartimento di Scienze Chimiche dell'Università di CamerinoVia S. Agostino 1 62032 Camerino ItalyDipartimento di Scienze Chimiche dell'Università di CamerinoVia S. Agostino 1 62032 Camerino ItalyDipartimento di Scienze Chimiche dell'Università di CamerinoVia S. Agostino 1 62032 Camerino Italy

It is well known the ability of primary and secondary nitroalkanes to generate carbanions (under basic conditions) strongly stabilized by the electron-withdrawing effect of the nitro group[1-4]. Thus, the main use of nitroalkanes is devoted to the generation of new carbon-carbon bonds through two principal approaches (Scheme 1): (i) reaction with carbonyl derivatives (nitroaldol-Henry-reaction), and (ii) Michael addition to electron poor alkenes.

关键词：化学变化合成工艺有机物亲电子稀烃

Petrography of Middle Jurassic to Early Cretaceous sandstones in the Kutch Basin,western India:Implications on provenance and basin evolution

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Journal of Palaeogeography 2018年第3期7卷 239-252页

作者： Angana Chaudhuri Santanu Banerjee Emilia Le Pera Department of Earth Sciences Indian Institute of Technology Bombay dipartimento di Biologia Ecologia e Scienze della Terra University della

This paper investigates the provenance of Middle Jurassic to Early Cretaceous sediments in the Kutch Basin, western India, on the basis of mineralogical investigations of sandstones composition （Quartz-Feldspar-Lithic （QFL） fragment）, Zircon-Tourmaline-Rutile （ZTR） index, and mineral chemistry of heavy detrital minerals of the framework. The study also examines the compositional variation of the sandstone in relation to the evolution of the Kutch Basin, which originated as a rift basin during the Late Triassic and evolved into a passive margin basin by the end Cretaceous. This study analyzes sandstone samples of Jhumara, Jhuran and Bhuj Formations of Middle Jurassic, Upper Jurassic and Lower Cretaceous, respectively, in the Kutch Mainland. Sandstones record a compositional evolution from arkosic to subarkosic as the feldspar content decreases from 68% in the Jhumara Formation to 27% in the Bhuj Formation with intermediate values in the Jhuran Formation. The QFL modal composition indicates basement uplifted and transitional continental settings at source. Heavy mineral content of these sandstones reveals the occurrence of zircon, tourmaline, rutile, garnet, apatite, monazite and opaque minerals. Sub-rounded to well-rounded zircon grains indicate a polycyclic origin. ZTR indices for samples in Jhumara, Jhuran and Bhuj Formations are 25%, 30% and 50% respectively. Chemistry of opaque minerals reveals the occurrence of detrital varieties such as ilmenite, rutile, hematite/magnetite and pyrite, in a decreasing order of abundances. Chemistry of ilmenites in the Jhumara Formation reveals its derivation from dual felsic igneous and metabasic source, while those in Jhuran and Bhuj Formations indicate a metabasic derivation. Chemistry of garnet reveals predominantly Fe-rich （almandine） variety of metabasic origin. X-ray microscopic study provides the percentage of heavy minerals ranging from 3% to 5.260. QFL detrital modes reflect the evolution of the basin from an active rif

关键词： Siliciclastic provenance Tectonic setting Heavy minerals Mineral chemistry X-ray microscopy Mesozoic,Kutch Basin

Connected Graphs Arising from Products of Veronese Varieties

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Algebra Colloquium 2016年第2期23卷 281-292页

作者： Gioia Failla Rosanna Utano Universita Mediterranea di Reggio Calabria DIIESVia Graziella Loc. Feo di Vito Reggio Calabria Italy Universita di Messina Dipartimento di Scienze Matematiehe e Informatiche Scienze Fisiche e Seienze della Terra ViMe Ferdinando Stagno D'Aleontres 31 98166 Messina Italy

Given a Segre squarefree Veronese configuration, following Bernd Sturmfels, we improve the study of the graphs associated to the configuration. We determine two special families of toric ideals and a finite set of moves for each of them, which still guarantee simultaneously the connection of all graphs arising from each family of moves.

关键词： graded algebras toric ideals semigroup rings graphs

Risk for gastric neoplasias in patients with chronic atrophic gastritis:A critical reappraisal

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World Journal of Gastroenterology 2012年第12期18卷 1279-1285页

作者： Lucy Vannella Edith Lahner Bruno Annibale dipartimento Medico-Chirurgico di scienze Cliniche Tecnobiomediche e Medicina TraslazionaleSant'Andrea HospitalSchool of MedicineUniversity Sapienza

Chronic atrophic gastritis （CAG） is an inflammatory condition characterized by the loss of gastric glandular structures which are replaced by connective tissue （non-metaplastic atrophy） or by glandular structures inappropriate for location （metaplastic atrophy）. Epidemiological data suggest that CAG is associated with two different types of tumors： Intestinal-type gastric cancer （GC） and type I gastric carcinoid （T I GC）. The pathophysiological mechanisms which lead to the development of these gastric tumors are different, It is accepted that a multistep process initiating from Helico- bacterpylori-related chronic inflammation of the gastric mucosa progresses to CAG, intestinal metaplasia, dysplasia and, finally, leads to the development of GC. The T I GC is a gastrin-dependent tumor and the chronic elevation of gastrin, which is associated with CAG, stimulates the growth of enterochromaffin-like cells with their hyperplasia leading to the development of T I GC. Thus, several events occur in the gastric mucosa before the development of intestinatype GC and/ or T I GC and these take several years. Knowledge ofCAG incidence from superficial gastritis, its prevalence in different clinical settings and possible risk factors as- sociated with the progression of this condition to gastric neoplasias are important issues. This editorial intends to provide a brief review of the main studies regarding incidence and prevalence of CAG and risk factors for the development of gastric neoplasias.

关键词： Chronic atrophic gastritis Gastric neoplasia Intestinal-type gastric cancer Type I gastric carcinoid Prevalence Incidence Risk factors

Calabrian and Ionian： A proposal for the definition of Mediterranean stages for the Lower and Middle Pleistocene

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Episodes 2006年第2期29卷 107-114页

作者： Maria Bianca Cita Luca Capraro Neri Ciaranfi Enrico di Stefano Maria Marino Domenico Rio Rodolfo Sprovieri Gian Battista Vai Universita di Milano Dipartimento di Scienze della Terra ‘Ardito Desio＇ via Mangiagalli 34. 20133 Milano Italy Universita di Padova Dipartimento di Geologia Paleontologia e Geofisica via Giottol 35137 Padova Italy Universita di Bari Dipartimento di Geologia e Geofisica via Orabona 4 70125 Bari Italy Universita di Palermo Dipartimento di Geologia e Geodesia corso Tukory 131 90134 Palermo Italy Universita di Bologna Dipartimento di Scienze della Terra e Geologico-Ambientali Piazza di Porta San Donato 140126 Bologna Italy

The need to standardise stratigraphical subdivisions of continuous marine sedimentary successions that outcrop for hundreds metres, using clearly defined points fixed in the field is strongly felt. A proposal is presented here to formalize regional stages for the Lower Pleistocene （Calabrian） and for the Middle Pleistocene （Ionian） in Italy. The sections are well exposed, carefully investigated using multiple criteria （an integrated stratigraphical approach） and located in the central part of the Mediterranean. This area is recognized worldwide as a classical region for the Neogene and the Pleistocene sequences. The terrestrial record is directly correlated with the deep-sea record, as determined from ODP Sites 653 （Tyrrhenian Sea）, 963 （Sicily Channel） and 964 （Ionian Sea）from the central Mediterranean. The present formal proposal is consistent with the INQUA and ICS decision to define and correlate the Plio/Pleistocene boundary （GSSP at Vrica） within the Olduvai Subchron, at 1.81 My, the Lower/Middle Pleistocene boundary at the Matuyama/Brunhes reversal at 0. 78 My and the Middle/ Upper Pleistocene boundary with the base of MIS 5, approximately 0. 13My. The present proposal also is consistent with the call for stage unit stratotypes that emphasize both the physical content of a stage and its boundaries （Hilgen et al., 2006）.

关键词：卡拉布里亚爱奥尼亚地中海更新世

Liver grafts from hepatitis B surface antigen-positive donors: A review of the literature

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World Journal of Gastroenterology 2016年第35期22卷 8010-8016页

作者： Elisabetta Loggi Fabio Conti Alessandro Cucchetti Giorgio Ercolani Antonio Daniele Pinna Pietro Andreone dipartimento di scienze Mediche e Chirurgiche Università degli Studi di Bologna Centro di Ricerca per lo Studio delle Epatiti Università degli Studi di Bologna

The scarcity of available organs and the gap between supply and demand continue to be the main limitations of liver transplantation. To relieve the organ shortage, current transplant strategies have implemented extended criteria, which include the use of liver from patients with signs of past or present hepatitis B virus(HBV) infection. While the use of liver grafts from donors with evidence of past HBV infection is quite limited, some data have been collected regarding the feasibility of transplanting a liver graft from a hepatitis B surface antigen(HBs Ag) positive donor. The aim of the present work was to review the literature regarding liver transplants from HBs Ag-positive donors. A total of 17 studies were identified by a search in Medline. To date, HBs Ag positive grafts have preferentially been allocated to HBs Ag positive recipients. The large majority of these patients continue to be HBs Ag positive despite the use of immunoglobulin, and infection prevention can only be guaranteed by using antiviral prophylaxis. Although serological persistence is evident, no significant HBV-related disease has been observed, except in patients coinfected with delta virus. Consistently less data are available for HBs Ag negative recipients, although they are mostly promising. HBs Agpositive grafts could be an additional organ source for liver transplantation, provided that the risk of reinfection/reactivation is properly prevented.

关键词： Liver transplantation Hepatitis B Marginal grafts Hepatitis B positive graft Hepatitis B surface antigen positive donor

Probabilistic Quantitative Temporal Constraints:Representing,Reasoning,and Query Answering

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Journal of Electronic Science and Technology 2018年第1期16卷 1-10页

作者： Paolo Terenziani Antonella Andolina dipartimento di scienze e Innovazione Tecnologica University of Eastern PiedmontAlessandria 15121 Istituto Tecnico Commerciale Sommeiller Torino 10129

In many applications and domains,temporal constraints between actions, and their probabilities play an important role. We propose the first approach in the literature coping with probabilistic quantitative constraints. To achieve such a challenging goal, we extend the widely used simple temporal problem(STP) framework to consider ***,we propose i) a formal representation of probabilistic quantitative constraints, ii) an algorithm,based on the operations of intersection and composition,for the propagation of such temporal constraints, and iii) facilities to support query answering on a set of such constraints. As a result, we provide users with the first homogeneous method supporting the treatment(representing,reasoning,and querying) of probabilistic quantitative constraints, as required by many applications and domains.

关键词： Artificial intelligence(AI) probabilities query answering quantitative temporal constraints temporal reasoning

A generalized approach for implicit time integration of piecewise linear/nonlinear systems

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International Journal of Mechanical System Dynamics 2021年第1期1卷 108-120页

作者： Huimin Zhang Runsen Zhang Andrea Zanoni Pierangelo Masarati School of Aeronautic Science and Engineering Beihang UniversityBeijingChina dipartimento di scienze e Tecnologie Aerospaziali Politecnico di MilanoMilanoItaly

A generalized solution scheme using implicit time integrators for piecewise linear and nonlinear systems is *** piecewise linear characteristic has been well‐discussed in previous studies,in which the original problem has been transformed into linear complementarity problems(LCPs)and then solved via the Lemke algorithm for each time *** proposed scheme,instead,uses the projection function to describe the discontinuity in the dynamics equations,and solves for each step the nonlinear equations obtained from the implicit integrator by the semismooth Newton *** with the LCP‐based scheme,the new scheme offers a more general choice by allowing other nonlinearities in the governing *** assess its performances,several illustrative examples are *** numerical solutions demonstrate that the new scheme can not only predict satisfactory results for piecewise nonlinear systems,but also exhibits substantial efficiency advantages over the LCP‐based scheme when applied to piecewise linear systems.

关键词： implicit time integrator piecewise linear and nonlinear systems projection function