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Competition between fusion-evaporation and multifragmentation in central collisions in ^(58)Ni+^(48)Ca at 25A MeV

Nuclear Science and Techniques 2013年第5期24卷 82-88页

作者： FRANCALANZA L ABBONDANNO U AMORINI F BARLINI S BINI M BOUgAULT R BRUNO M CARDELLA g CASINI g AgOSTINO M D' De FILIPPO V De SANCTIS J gERACI E gIUSSANI A gRAMEgNA F gUIOT B KRAVCHUK V La gUIDARA E LANZALONE g Le NEINDRE N MAIOLINO C MARINI P MORELLI L OLMI A PAgANO A PAPA M PIANTELLI S PIRRONE S politi g POggI g PORTO F RUSSOTTO P RIZZO F VANNINI g VANNUCCI L INFN Laboratori Nazionali del Sud-LNS Catania 95123Italy Dipartimento di Fisica Universitàdi Catania I-95129Italy INFN Sezione di Trieste Trieste I-34127Italy Dipartimento di Fisica Universitàdi FirenzeINFN Sezione di Firenze 1-50139Italy LPC Caen IN2P3-CNRS/ENSICAEN and UniversitéF-14050 Caen cedex 5-140France Dipartimento di Fisica Universitàdi Bologna and INFN Sezione di Bologna 4-50121Italy INFN Sezione di Catania I-95129 Italy INFN Sezione di Firenze I-50139 Italy Dipartimento di Fisica Universitàdi Milano and INFN Sezione di Milano1-20126Italy INFN Laboratori Nazionali di Legnaro 1-35020 Italy Centro Siciliano di Fisica Nucleare e Struttura della Materia Catania 1-95129Italy UniversitàKore Enna 1-94100Italy

The experimental data concerning the58Ni+48Ca reaction at Elab(Ni)=25A MeV,collected by using the CHIMERA 4π device,have been analyzed in order to investigate the competition among different reaction mechanisms for central collisions in the Fermi energy domain.As a main criterion for centrality selection we have chosen the flow angle(flow) method,making an event-by-event analysis that considers the shape of events,as it is determined by the eigenvectors of the experimental kinetic-energy tensor.For the selected central events(flow >60°) some global variables,good to characterize the pattern of central collisions have been constructed.The main features of the reaction products were explored by using different constraints on some of the relevant observables,like mass and velocity distributions and their correlations.Much emphasis was devoted,for central collisions,to the competition between fusion-evaporation processes with subsequent identification of a heavy residue and a possible multifragmentation mechanism of a well defined(if any) transient nuclear system.Dynamical evolution of the system and pre-equilibrium emission were taken into account by simulating the reactions in the framework of transport theories.Different approaches have been envisaged(dynamical stochastic BNV calculations + sequential SIMON code,QMD,CoMD,etc.).Preliminary comparison of the experimental data with BNV calculations shows reasonable agreement with the assumption of sequential multifragmentation emission in the mass region of IMFs close to the heavy residues.Possible deviations from sequential processes were found for those IMFs in the region of masses intermediate between the mass of heavy residues and the mass of light IMFs.Further simulations are in progress.The experimental analysis will be enriched also by information obtained inspecting the IMF-IMF correlation function,in order to elucidated the nature of space-time decay property of the emitting source associated with events having the largest IMF multiplicity.

关键词：多重碎裂中心碰撞蒸发过程 MeV 竞争熔合国际货币基金组织事件分析

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Potential applications of 7 Tesla magnetic resonance imaging in paediatric neuroimaging:Feasibility and challenges

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World Journal of Clinical Pediatrics 2024年第2期13卷 1-6页

作者： Arosh S Perera Molligoda Arachchige Letterio S politi Final Year Medical Student Faculty of MedicineHumanitas UniversityPieve Emanuele 20089Italy Department of Neuroradiology IRCCS Humanitas Research HospitalRozzano 20089MilanItaly Department of Biomedical Sciences Humanitas UniversityPieve Emanuele 20072MilanItaly

The integration of 7 Tesla magnetic resonance imaging(7 T MRI)in adult patients has marked a revolutionary stride in radiology.In this article we explore the feasibility of 7 T MRI in paediatric practice,emphasizing its feasibility,applications,challenges,and safety considerations.The heightened resolution and tissue contrast of 7 T MRI offer unprecedented diagnostic accuracy,particularly in neuroimaging.Applications range from neuro-oncology to neonatal brain imaging,showcasing its efficacy in detecting subtle structural abnormalities and providing enhanced insights into neurological conditions.Despite the promise,challenges such as high cost,discomfort,and safety concerns necessitate careful consideration.Research suggests that,with precautions,7 T MRI is feasible in paediatrics,yet ongoing studies and safety assessments are imperative.

关键词： 7 Tesla magnetic resonance imaging Pediatric imaging Feasibility Challenges

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From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging

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World Journal of Radiology 2024年第1期16卷 20-31页

作者： Arosh S Perera Molligoda Arachchige Ana Claudia Teixeira de Castro gonçalves Ortega Federica Catapano Letterio S politi Michael N Hoff Faculty of Medicine Humanitas UniversityPieve Emanuele 20072MilanItaly Department of Biomedical Sciences Humanitas UniversityPieve Emanuele 20072MilanItaly IRCCS Humanitas Research Hospital Rozzano 20089MilanItaly Department of Neuroradiology IRCCS Humanitas Research HospitalRozzano 20089MilanItaly Department of Radiology and Biomedical Imaging University of CaliforniaSan FranciscoCA 94143United States

BACKgROUND After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging(MRI)have demonstrated the feasibility as well as diagnostic capabilities of liver,kidney,and prostate MRI at 7-Tesla.However,the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks,primarily stemming from heightened artifacts and limitations in Specific Absorption Rate,etc.Furthermore,evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence.AIM To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends,details relevant challenges,and provides a concise set of potential solutions.METHODS This systematic review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.A PubMed search,utilizing Medical Subject Headings terms such as"7-Tesla"and organ-specific terms,was conducted for articles published between January 1,1985,and July 25,2023.Eligibility criteria included studies exploring 7T MRI for imaging human abdominal organs,encompassing various study types(in-vivo/ex-vivo,method development,reviews/meta-analyses).Exclusion criteria involved animal studies and those lacking extractable data.Study selection involved initial identification via title/abstract,followed by a full-text review by two researchers,with discrepancies resolved through discussion.Data extraction covered publication details,study design,population,sample size,7T MRI protocol,image characteristics,endpoints,and conclusions.RESULTS The systematic review included a total of 21 studies.The distribution of clinical 7T abdominal imaging studies revealed a predominant focus on the prostate(n=8),followed by the kidney(n=6)and the hepatobiliary system(n=5).Studies on these organs,and

关键词： 7-Tesla magnetic resonance imaging Abdominal Prostate Kidney Renal Pancreas Hepatobiliary Liver Small bowel

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Identification of tree groups used by secondary cavity-nesting birds to simplify forest management in subtropical forests

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Journal of Forestry Research 2020年第4期31卷 1417-1424页

作者： Alejandro A.Schaaf Román A.Ruggera Ever Tallei Constanza g.Vivanco Luis Rivera Natalia politi Instituto de Ecorregiones Andinas(INECOA) Universidad Nacional de Jujuy–Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Av.Bolivia 12394600 San Salvador de JujuyJujuyArgentina Fundación CEBio Roca 444600 San Salvador de JujuyJujuyArgentina

In tropical and subtropical forest ecosystems,cavities formed by decay processes are a key but scarce resource for birds that nest and roost in them,which makes them a highly sensitive group to logging.The piedmont forest of northwestern Argentina is a complex ecosystem with 113 tree and 120 bird species.It has high logging pressure on the few,well-conserved forest remnants,complicating the delineation of sustainable management guidelines for each tree or bird species in a short time.Our objective was to reduce the complexity of subtropical forests by grouping tree species according to the characteristics used by secondary cavity-nesting birds(i.***.non excavators).In the piedmont forest,50 plots of 0.25 ha were sampled to record cavity trees and cavity characteristics.These were then used in a cluster analysis to form tree groups.Additionally,cavities were searched to identify the bird species using the decay-formed cavities.A total of 187 cavity trees,comprising 23 tree species,were recorded,and these formed four tree groups or clusters.We recorded 86 cavities that were used by secondary cavitynesting bird species.The four tree groups were unequally used by secondary cavity nesters.The tree group that included valuable timber species(Myroxylon peruiferum,Anadenanthera colubrina and Calycophyllum multiflorum)and had the greatest cavity availability represented 71%of total cavity use.Another tree group with valuable timber species(Cedrela balansae and Amburana cearensis),measured>73 cm DBH and>21 m tall,had cavity entrances>0.10 cm2,and contributed 14%of all cavity use by birds.A third group had no highly economically valuable tree species,and included the snag category(i.***.standing dead trees)as well as a 15%of cavity use.The fourth tree group had a DBHghly economically valuable tree species(Cordia trichotoma),and supported no cavity use.The clustering of subtropical trees can reduce the complexity of these forests,hence easing their management by focusing on those groups with tree species show

关键词： Biodiversity Cavity-nesting birds Conservation Logging

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Retina stem cells,hopes and obstacles

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World Journal of Stem Cells 2021年第10期13卷 1446-1479页

作者： Olga L german Harmonie Vallese-Maurizi Tamara B Soto Nora P Rotstein Luis Enrique politi Department of Biology Biochemistry and PharmacyUniversidad Nacional del SurBahia blanca 8000Buenos AiresArgentina Department of Biology Biochemistry and PharmacyUniversidad Nacional del Surand Neurobiology DepartmentInstituto de Investigaciones Bioquímicas de Bahía Blanca(INIBIBB)ConicetBahía Blanca 8000Buenos AiresArgentina

Retinal degeneration is a major contributor to visual dysfunction worldwide.Although it comprises several eye diseases,loss of retinal pigment epithelial(RPE)and photoreceptor cells are the major contributors to their pathogenesis.Early therapies included diverse treatments,such as provision of anti-vascular endothelial growth factor and many survival and trophic factors that,in some cases,slow down the progression of the degeneration,but do not effectively prevent it.The finding of stem cells(SC)in the eye has led to the proposal of cell replacement strategies for retina degeneration.Therapies using different types of SC,such as retinal progenitor cells(RPCs),embryonic SC,pluripotent SCs(PSCs),induced PSCs(iPSCs),and mesenchymal stromal cells,capable of self-renewal and of differentiating into multiple cell types,have gained ample support.Numerous preclinical studies have assessed transplantation of SC in animal models,with encouraging results.The aim of this work is to revise the different preclinical and clinical approaches,analyzing the SC type used,their efficacy,safety,cell attachment and integration,absence of tumor formation and immunorejection,in order to establish which were the most relevant and successful.In addition,we examine the questions and concerns still open in the field.The data demonstrate the existence of two main approaches,aimed at replacing either RPE cells or photoreceptors.Emerging evidence suggests that RPCs and iPSC are the best candidates,presenting no ethical concerns and a low risk of immunorejection.Clinical trials have already supported the safety and efficacy of SC treatments.Serious concerns are pending,such as the risk of tumor formation,lack of attachment or integration of transplanted cells into host retinas,immunorejection,cell death,and also ethical.However,the amazing progress in the field in the last few years makes it possible to envisage safe and effective treatments to restore vision loss in a near future.

关键词： Retina regeneration Stem cells Retina stem cell transplantation Cancer stem cells Photoreceptor replacement

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PURIFICATION OF BLOOD ULTRAFILTRATE ON UNCOATED CHARCOAL

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CHINESE MEDICAL JOURNAL 1988年第6期101卷 438-43页

作者： Laura politi Nicola Cerullio Anna Rita D’Angeloo Roberto Scandurra DipartitmentodiScienzeBiochimicheandIstitutodiUroilogiao Universita'LaSapienza' Roma Italy

Dialysis is an insufficient depurative procedure since many substances are poorly removed. To improve the depuration, uremic patients were daily treated with 3-hour perfusion on uncoated granular charcoal (0.5 Kg) followed by 1-hour dialysis for 16 times for the removal of urea and electrolytes not absorbed by charcoal. The results showed that a granular uncoated charcoal removed from uremic ultrafiltrates many chemical species which were scarcely removed by dialysis. The conditions of the patients were improved and could be maintained for one-week charcoal treatment between two dialyses. This depurative procedure has been well documented by chromatography on Biogel P2.

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Circulating adhesion molecules in patients with virus-related chronic diseases of the liver

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World Journal of gastroenterology 2005年第29期11卷 4566-4569页

作者： Cosimo Marcello Bruno Claudio Sciacca Danila Cilio gaetano Bertino Anna Elisa Marchese gaetana politi Lucia Chinnici Department of Internal Medicine and Systemic Diseases University of Catania Italy Lucia Chinnici Clinical Laboratory Analysis S. Bambino Hospital Catania Italy

AIM: In the inflammatory state, intercellular adhesion molecule-1 (ICAM-1) and vascular cellular adhesion molecule-1 (VCAM-1) play a key role in promoting migration of immunological cells from the circulation to target site.Aim of our study was to investigate soluble forms of these molecules in patients with virus-related chronic liver diseases, to assess their behavior in different pathologies and correlation with severity of liver damage.METHODS: Circulating ICAM-1 and VCAM-1 were assayed by EIA commercial kits (R&D System Co.,Abington, UK) in 23 patients with chronic active hepatitis (CH), 50 subjects affected by liver cirrhosis (LC) and 15 healthy controls comparable for sex and age. In patients, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were also detected by autoanalyzer.RESULTS: LC patients had significantly higher ICAM-1 values than CH patients (38.56±7.4 ng/mL vs 20.89±6.42 ng/mL; P＜0.001) and these ones had significantly higher values than controls (12.92±1.08 ng/mL; P＜0.001). In CH group, ICAM-1 levels were significantly related to inflammatory activity (P= 0.041) and ALT values (r= 0.77;P＜0.05). VCAM-1 values were significantly increased only in LC patients (P＜0.001) and related to severity of liver impairment.CONCLUSION: These findings suggest that the determination of serum ICAM-1 can be considered as an additional useful marker of hepatocellular necrosis and inflammatory activity in chronic hepatitis, while serum VCAM-1 is an indicator of liver fibrogenesis and severity of disease in cirrhosis.

关键词：循环支持分子病毒感染慢性肝疾病免疫机制

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众说纷纭意大利当代艺术收藏

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东方艺术 2009年第9期 98-99页

作者： giancarlo politi

1.你对当前的意大利艺术有什么看法？你认为它可以满足那些苛求的收藏者吗？ 2.展望意大利画廊的前景,好像世界艺术产业的＂最底端＂？

关键词：艺术收藏意大利艺术产业收藏者画廊艺术家世界

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意大利博物馆与基金会

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东方艺术 2009年第9期 100-101页

作者： giancarlo politi

相对于您的外国同事们而言,意大利环境下的当代艺术博物馆/基金会工作意味着什么?有什么优势和劣势吗?

关键词：艺术博物馆基金会意大利意味

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特别报道：国际艺术博览会专访——艺术博览会与艺术市场的现状和展望

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东方艺术 2007年第17期 116-123页

作者： giancarlo politi Cissy 吴子茹

艺术博览会是目前世界上规模最大的艺术品展示和交易活动。作为艺术与市场的集大成者,它是从包罗万象的更大的综合性市场运作模式——博览会中剥离而独立出来的。1851年,英国阿尔帕特亲王创办了英国首届世界博览会——"大不列颠"博览会... 详细信息

艺术博览会是目前世界上规模最大的艺术品展示和交易活动。作为艺术与市场的集大成者,它是从包罗万象的更大的综合性市场运作模式——博览会中剥离而独立出来的。1851年,英国阿尔帕特亲王创办了英国首届世界博览会——"大不列颠"博览会,这是世界上第一个博览会。1889年,在法国大革命一百周年之际,巴黎举办了法国首届世界博览会。那座至今仍然高耸入云、作为巴黎象征的艾菲尔铁塔,当年就是为这个博览会而建造的。而冠以"艺术"之名的博览会的开办则要迟得多。尽管艺术博览会可以在17世纪欧洲的一些艺术集市找到源头,上世纪30年代的英国伦敦哥罗维诺古董展也可视为艺术博览会的雏形,但真正意义上的艺术博览会则是在与世界博览会相隔一个多世纪之后才出现的,1967年德国科隆创办了世界上第一个艺术博览会——科隆国际艺术博览会,正式拉开了世界艺博会的帷幕。在此之后的短短40年间,世界上许多大城市群起仿效,形成了一股举办艺博会的热潮,而且至今仍保持着强劲的势头,长盛不衰。尤其是当代艺术市场的兴起和无限的发展趋势,使国际艺术博览会就此插上了全球化的翅膀,随着艺术市场的火热而渐趋繁荣,是否它已经取代了传统商业画廊的角色?成为艺术市场的新宠?甚至它的功能和扮演的角色已经得到了艺术家的认可?加之数量庞大的艺术观众、专注艺术品市场的收藏家和投资者是否也已将更多的注意力转向艺术博览会?众多因素汇聚,再有诸大艺术拍卖公司的推波助澜,似乎国际艺术博览会已然成为全球化艺术市场中的大鳄。事实是否真的如此?我们策划了这次广泛的调查专访,对象当然是目前世界上最有影响力的艺术博览会。通过这次调查专访,我们试图深入这些重要的博览会的组织策划内部,通过对这些博览会的负责人专访,得到我们想知道的,也是每一个关注艺术市场和艺术未来的人所关注的问题的答案。

关键词：世界博览会艺术市场艺术品市场艺术家当代艺术巴塞尔收藏家艺博会现代艺术国际化

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