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A model to explain the angular distribution of J/Ψ and Ψ(2S) decay into ■ and ■

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Chinese Physics C 2019年第2期43卷 31-36页

作者： M.Alekseev A.Amoroso R.Baldini Ferroli I.Balossino M.Bertani D.Bettoni F.Bianchi J.Chai G.Cibinetto F.Cossio F.De Mori M.Destefanis R.Farinelli L.Fava G.Felici I.Garzia M.Greco L.Lavezzi C.Leng M.Maggiora A.Mangoni S.Marcello G.Mezzadri S.Pacetti P.Patteri A.Rivetti M.Da Rocha Rolo M.Savrié S.Sosio S.Spataro L.Yan Università di Torino infn Sezione di Torino infn Laboratori Nazionali di Frascati infn Sezione di Ferrara Institute of High Energy Physics Università di Ferrara Università del Piemonte Orientale Università di perugia infn Sezione di perugia

BESⅢ data show a particular angular distribution for the decay of J/Ψ and Ψ(2 S) mesons into ■ and Σ~0Σ~0 hyperons: the angular distribution of the decay Ψ(2 S) →Σ~0Σ~0 exhibits an opposite trend with respect to the other three channels: J/Ψ→■, J/Ψ→Σ~0Σ~0 and Ψ(2 S) →■. We define a model to explain the origin of this phenomenon.

关键词： J/ψandψ(2S)hadronic decays effective Lagrangian model polarization parameters

The Energy Spectrum of Ultraheavy Nuclei above 10<sup>20</sup>eV

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Journal of Applied Mathematics and Physics 2017年第8期5卷 1540-1550页

作者： Antonio Codino university of perugia and infn Perugia Italy

A major feature of the energy spectrum of the cosmic radiation above 1019 eV is the increasing fraction of heavy nuclei with respect to light nuclei. This fact, along with other simple assumptions, is adopted to calculate the energy spectrum of the cosmic radiation up to 2.4 × 1021 eV. The predicted spectrum maintains the index of 2.67 observed at lower energies which is the basic, known, empirical well-assessed feature of the physical mechanism accelerating cosmic rays in the Galaxy. Indeed above 1019 eV the injection of nuclei is inhibited by some filter and this inhibition causes a staircase profile of the energy spectrum. It is argued that particle injection failure versus energy commences with protons, followed by Helium and then by other heavier nuclei up to Uranium. Around 7.5 × 1020 the cosmic radiation consists solely of nuclei heavier than Copper and the estimated intensity is 1.8 × 10-30 particles/GeV s sr m2.

关键词： Ankle Energy Ultra-High Energy GZK Effect Ultraheavy Nuclei

Cognitive impairment in multiple sclerosis: lessons from cerebrospinal fluid biomarkers

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Neural Regeneration Research 2021年第1期16卷 36-42页

作者： Lorenzo Gaetani Nicola Salvadori Elena Chipi Lucia Gentili Angela Borrelli Lucilla Parnetti Massimiliano Di Filippo Section of Neurology Department of MedicineUniversity of PerugiaPerugiaItaly

Cognitive impairment is a common clinical manifestation of multiple sclerosis,but its pathophysiology is not completely *** and grey matter injury together with synaptic dysfunction do play a *** measurement of biomarkers in the cerebrospinal fluid and the study of their association with cognitive impairment may provide interesting in vivo evidence of the biological mechanisms underlying multiple sclerosis-related cognitive *** far,only a few studies on this topic have been published,giving interesting results that deserve further *** fluid biomarkers of different pathophysiological mechanisms seem to reflect different neuropsychological patterns of cognitive deficits in multiple *** aim of this review is to discuss the studies that have correlated cerebrospinal fluid markers of immune,glial and neuronal pathology with cognitive impairment in multiple *** preliminary,these findings suggest that cerebrospinal fluid biomarkers show some correlation with cognitive performance in multiple sclerosis,thus providing interesting insights into the mechanisms underlying the involvement of specific cognitive domains.

关键词： biomarkers cerebrospinal fluid cognitive impairment information processing speed memory multiple sclerosis

Desmosterol, the main sterol in rabbit semen： distribution among semen subfractions and its role in the in vitro spermatozoa acrosome reaction and motility

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Asian Journal of Andrology 2010年第6期12卷 862-870页

作者： Evangelia Mourvaki Raffaella Cardinali Rita Roberti Alessandro Dal Bosco Cesare Castellini Department of Applied Biology Section of Animal Science University of Perugia Perugia 06100 Italy Department of Internal Medicine Section of Biochemistry University of Perugia Perugia 06122 Italy

Sterols are essential components of the cell membrane lipid bilayer that include molecules such as cholesterol and desmosterol, which are significantly found in the spermatozoa of several animal species. However, the presence of desmosterol in rabbit semen has never been investigated. The aims of this study were to characterize the sterol composition of subfractions of ejaculated rabbit semen and evaluate the in vitro effects of sterol on the spermatozoa acrosome reaction and motility. Two sterols, occurring prevalently in the free form （94.3%）, were identified in whole semen collected from 10 fertile New Zealand White rabbits, specifically desmosterol （58.5% of total sterols） and cholesterol （35.9% of total sterols）. Desmosterol was the predominant sterol found in all subfractions of rabbit semen, varying from 56.7% （in the prostatic secretory granules, PSGs） to 63.8% （in the seminal plasma）. Spermatozoa contained an intermediate proportion of desmosterol （59.8%）, which was asymmetrically distributed between the heads （52.0% of the total content of sterols） and the tails （81.8%）. Results showed that both desmosterol and cholesterol can be transferred from the PSGs to the spermatozoa and are equally effective in inhibiting in vitro spermatozoa capacitation at a concentration higher than 1 mg L^-1. In contrast, neither desmosterol nor cholesterol had a significant effect on spermatozoa motility. Thus, it was concluded that, the various fractions of rabbit seminal fluid differ from each other in sterol composition and quantity, probably due to their different functional properties, and these fractions may undergo significant sterol changes depending on the stage of spermatozoa capacitation.

关键词： acrosome reaction cholesterol desmosterol motility prostatic secretory granules rabbit seminal plasma spermatozoa head spermatozoa tail

High intensity focused ultrasound,liver disease and bridging therapy

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World Journal of Gastroenterology 2013年第43期19卷 7494-7499页

作者： Mearini Luigi Deparment of Urology University of PerugiaAzienda Ospedaliera di Perugia06100 PerugiaItaly

High-intensity focused ultrasound(HIFU)is a noninvasive modality that uses an extracorporeal source of focused ultrasound *** technique was introduced by Lynn et al and is able to induce coagulative necrosis in selected tissues without damaging adjacent *** HIFU has been studied for 50years,recent technological developments now allow its use for tumours of the liver,prostate and other *** liver disease,HIFU has been used to treat unresectable,advanced stages of hepatocellular carcinoma(HCC)and liver *** carcinoma is a serious health problem worldwide and is endemic in some areas because of its association with hepatitis B and C viruses(in 20%of cases).Liver transplantation(LT)has become one of the best treatments available because it removes both the tumour and the underlying liver disease such as cirrhosis(which is present in approximately 80%of cases).The prerequisite for longterm transplant success depends on tumour load and strict selection criteria regarding the size and number of tumour *** need to obtain the optimal benefit from the limited number of organs available has prompted strict selection criteria limited to only those patients with early HCC who have a better long-term outcome after *** so-called"bridging therapy"has the aim of controlling disease burden for patients who are on the organ transplant waiting *** various treatment options,transarterial chemoembolisation and radiofrequency ablation are the most popular treatment ***,Cheung et al demonstrated that HIFU ablation is a safe and effective method for the treatment of HCC patients with advanced cirrhosis as a bridging therapy and that it reduced the dropout rate from the liver transplant waiting *** this commentary,we discuss the current value of HIFU in the treatment of liver disease,including its value as a bridging therapy,and examine the potential advantages of other therapeutic strategies.

关键词： High-intensity focused ultrasound Hepatocellular carcinoma Liver transplantation Bridging therapy Waiting list

Cytokines,synaptic plasticity and network dynamics:a matter of balance

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Neural Regeneration Research 2023年第12期18卷 2569-2572页

作者： Laura Bellingacci Jacopo Canonichesi Andrea Mancini Lucilla Parnetti Massimiliano Di Filippo Section of Neurology Department of Medicine and SurgeryUniversity of PerugiaPerugiaItaly

The modern view of the immune system as a sensitizing and modulating machinery of the central nervous system is now well ***,the specific mechanisms underlying this fine crosstalk have yet to be fully *** control cognitive function and behavior,the two systems are engaged in a subtle interacting *** this scenario,a dual action of pro-inflammatory cytokines in the modulation of brain network connections is ***-inflammatory cytokines are indeed required to express physiological plasticity in the hippocampal network while being detrimental when over-expressed during uncontrolled inflammatory *** this dynamic equilibrium,synaptic functioning and the performance of neural networks are ensured by maintaining an appropriate balance between pro-and anti-inflammatory molecules in the central nervous system microenvironment.

关键词： brain networks cognition cytokines hippocampus memory neuroimmunology neuroinflammation synaptic plasticity

Unveiling the geometric meaning of quantum entanglement:Discrete and continuous variable systems

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Frontiers of physics 2024年第5期19卷 193-206页

作者： Arthur Vesperini Ghofrane Bel-Hadj-Aissa Lorenzo Capra Roberto Franzosi DSFTA University of SienaVia Roma 5653100 SienaItaly QSTAR&CNR-Istituto Nazionale di Ottica Largo Enrico Fermi 2I-50125 FirenzeItaly infn Sezione di perugia I-06123 PerugiaItaly

We show that the manifold of quantum states is endowed with a rich and nontrivial geometric *** derive the Fubini−Study metric of the projective Hilbert space of a multi-qubit quantum system,endowing it with a Riemannian metric structure,and investigate its deep link with the entanglement of the states of this *** a measure,we adopt the entanglement distance E preliminary proposed in ***.A 101,042129(2020).Our analysis shows that entanglement has a geometric interpretation:E(|ψ>)is the minimum value of the sum of the squared distances between|ψ>and its conjugate states,namely the statesυ^(μ).σ^(μ)|ψ>,whereυ^(μ)are unit vectors andμruns on the number of *** the proposed geometric approach,we derive a general method to determine when two states are not the same state up to the action of local unitary ***,we prove that the entanglement distance,along with its convex roof expansion to mixed states,fulfils the three conditions required for an entanglement measure,that is:i)E(|ψ>)=0 iff|ψ>is fully separable;ii)E is invariant under local unitary transformations;iii)E does not increase under local operation and classical *** different proofs are provided for this latter *** also show that in the case of two qubits pure states,the entanglement distance for a state|ψ>coincides with two times the square of the concurrence of this *** propose a generalization of the entanglement distance to continuous variable ***,we apply the proposed geometric approach to the study of the entanglement magnitude and the equivalence classes properties,of three families of states linked to the Greenberger−Horne−Zeilinger states,the Briegel Raussendorf states and the W *** an example of application for the case of a system with continuous variables,we have considered a system of two coupled Glauber coherent states.

关键词： entanglements quantum information entanglement measure

Bile acid activated receptors: Integrating immune and metabolic regulation in non-alcoholic fatty liver disease

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Liver Research 2021年第3期5卷 119-141页

作者： Michele Biagioli Stefano Fiorucci Department of Medicine and Surgery University of PerugiaPerugiaItaly

Bile acids are a family of atypical steroids generated at the interface of liver-intestinal microbiota acting on a ubiquitously expressed family of membrane and nuclear receptors known as bile acid activated *** two best characterized receptors of this family are the nuclear receptor,farnesoid X re-ceptor(FXR)and the G protein-coupled receptor,G protein-coupled bile acid receptor 1(GPBAR1).FXR and GPBAR1 regulate major aspects of lipid and glucose metabolism,energy balance,autophagy and immunity and have emerged as potential pharmaceutical targets for the treatment of metabolic and inflammatory *** trials in non-alcoholic fatty liver disease(NAFLD),however,have shown that selective FXR agonists cause side effects while their efficacy is *** FXR and GPBAR1 exert additive effects,dual FXR/GPBAR1 ligands have been developed for the treatment of metabolic disorders and are currently advanced to clinical ***,we will review the role of FXR and GPBAR1 agonism in NAFLD and how the two receptors could be exploited to target multiple components of the disease.

关键词： Bile acid Farnesoid X receptor(FXR) G protein-coupled bile acid receptor 1(GPBAR1) Immunity Lipid metabolism Non-alcoholic fatty liver disease(NAFLD) Non-alcoholic steatohepatitis(NASH)

Gastrointestinal and hepatic involvement during COVID-19 pandemic: A focus on pediatric population and possible future implications

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World Journal of Gastroenterology 2021年第40期27卷 7000-7004页

作者： Rossella Sica Serena Pennoni Laura Penta Sara Riccioni Giuseppe Di Cara Alberto Verrotti Department of Pediatrics University of PerugiaPerugia 06132PGItaly

Since the coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has rapidly spread worldwide,there is still limited knowledge about this condition and its natural *** have been relatively spared during COVID-19 pandemic but a novel syndrome known as multisystem inflammatory syndrome(MIS-C)has emerged,following a SARS-CoV-2 infection in children and *** syndrome can lead to shock and multiple organ failure requiring intensive *** COVID-19 clinical research focuses on respiratory symptoms,extrapulmonary involvement such as gastrointestinal(GI)and hepatic manifestations should also be *** fact,GI and hepatic involvement play an important role among the most common presenting symptoms of both pediatric and adult COVID-19 and *** involvement can not only be one of the most common presenting clinical features but also one of the sequelae of these *** ultrasonography monitoring could be very useful to identify a potential involvement of the GI tract and ***,long-term follow-up is needed and would be essential to define the long-term outcomes of these patients.

关键词： SARS-CoV-2 COVID-19 Multisystem inflammatory syndrome Gastrointestinal tract Liver Ultrasonography