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Petroleum 2019年第2期5卷 191-198页

作者： Arianna Bonzanini Davide Picchi Marco Ferrari pietro Poesio Dipartimento di Ingegneria Meccanica ed Industriale Universita degli Studi di BresciaVia Branze3825123BresciaItaly Energy Resources Engineering Stanford UniversityStanford94305CAUnited States department of Mathematics Politecnico di Milanop.zza Leonardo da Vinci3220133MilanItaly

In a previous work it has been shown that a one-dimensional,hyperbolic,transient five equations twofluid model is able to numerically describe stratified,wavy,and slug flow in horizontal and nearhorizontal *** statistical characteristics can be numerically predicted with results in good agreement with experimental data and well-known empirical *** this model some approximated and simplified assumptions are adopted to describe shear stresses at wall and at phase *** this paper,we focus on the possibility to account for the cross sectional flow by inserting shape factors into the momentum balance equations of the aforementioned *** profiles are obtained by a pre-integrated model and they are computed at each time step and at each computational *** that the velocity profiles are known,the obtained shape factors are inserted in the numerical *** this way it is possible to recover part of the information lost due to the one-dimensional flow *** profiles computed in stratified conditions are compared against experimental profiles measured by PIV technique;a method to compute the velocity profile during slug initiation and growth has been developed and the computed velocity distribution in the liquid phase was compared against the one-seventh power law.

关键词： Multi-phase pipeline transport Oil&gas Hyperbolic two-fluid model Velocity profiles Shape factors

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World Journal of gastroenterology 2021年第42期27卷 7299-7310页

作者： Sinan Sadalla Andrea Lisotti Lorenzo Fuccio pietro Fusaroli UnitàOperativa Complessa di gastroenterologia e Endoscopia Digestiva Universitàdi Bologna/Ospedale di ImolaImola(BO)40024Italy UnitàOperativa Complessa di gastroenterologia e Endoscopia Digestiva Universitàdi Bologna/Ospedale di ImolaImola(BO)40026Italy Divisione di gastroenterologia Dipartimento di Scienze Medico-Chirurgiche(DIMEC)IRCSS-Azienda Ospedaliero-Universitaria di BolognaBologna 40138Italy

Colonoscopy is a risk factor for colon *** colon is susceptible to ischemia due to its minor blood flow compared to other abdominal organs;the etiology of colon ischemia after colonoscopy is *** causative mechanisms include splanchnic circulation impairment,bowel preparation,drugs used for sedation,bowel wall ischemia due to insufflation/barotrauma,and introduction of the *** must be aware of this condition and its risk factors for risk minimization,early diagnosis,and proper treatment.

关键词： Endoscopy Colon ischemia Colonoscopy Bowel preparation Mesenteric circulation Ischemic colitis

Viral hepatitis:Milestones,unresolved issues,and future goals

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World Journal of gastroenterology 2021年第28期27卷 4603-4638页

作者： pietro Torre Andrea Aglitti Mario Masarone Marcello Persico Internal Medicine and Hepatology Unit Department of MedicineSurgery and Dentistry“Scuola Medica Salernitana”University of SalernoSalerno 84081Italy

In this review the current overall knowledge on hepatitis A,B,C,D,and E will be *** diseases are all characterized by liver inflammation but have significant differences in distribution,transmission routes,and *** B virus and hepatitis C virus are transmitted by exposure to infected blood,and in addition to acute infection,they can cause chronic hepatitis,which in turn can evolve into *** is estimated that more than 300 million people suffer from chronic hepatitis B or C *** D virus,which is also transmitted by blood,only affects hepatitis B virus infected people,and this dual infection results in worse liver-related *** A and E spread via the fecal-oral route,which corresponds mainly to the ingestion of food or water contaminated with infected ***,in developed countries hepatitis E is predominantly a *** hepatitis A virus and hepatitis E virus are usually responsible for a self-limiting hepatitis,a serious,rarely fatal illness is also possible,and in immunosuppressed patients,such as organ transplant recipients,hepatitis E virus infection can become *** description of goals achieved,unresolved issues,and the latest research on this topic may make it possible to speculate on future scenarios in the world of viral hepatitis.

关键词： Viral hepatitis Hepatitis A Hepatitis B Hepatitis C Hepatitis D Hepatitis E

Experimental Analysis of the Aerodynamic Performance of an Innovative Low Pressure Turbine Rotor

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Journal of Thermal Science 2016年第1期25卷 22-31页

作者： Infantino Daniele Satta Francesca Simoni Daniele Ubaldi Marina Zunino pietro Bertini Francesco DIME-Universita degli Studi di genova Via MontaUegro 11-16145 GenovaItaly Avio Aero Viale I Maggio 56I-10040 Rivalta(TO)-Italy

In the present work the aerodynamic performances of an innovative rotor blade row have been experimentally investigated. Measurements have been carried out in a large scale low speed single stage cold flow facility at a Reynolds number typical of aeroengine cruise, under nominal and off-design conditions. The time-mean blade aerodynamic loadings have been measured at three radial positions along the blade height through a pressure transducer installed inside the hollow shaft, by delivering the signal to the stationary frame with a slip ring. The time mean aerodynamic flow fields upstream and downstream of the rotor have been measured by means of a five-hole probe to investigate the losses associated with the rotor. The investigations in the single stage research turbine allow the reproduction of both wake-boundary layer interaction as well as vortex-vortex interaction. The detail of the present results clearly highlights the strong dissipative effects induced by the blade tip vortex and by the momentum defect as well as the turbulence production, which is generated during the migration of the stator wake in the rotor passage. Phase-locked hot-wire investigations have been also performed to analyze the time-varying flow during the wake passing period. In particular the interaction between stator and rotor structures has been investigated also under off-design conditions to further explain the mechanisms contributing to the loss generation for the different conditions.

关键词： Low Pressure Turbine Single Stage Research Turbine Rotor Aerodynamic Loading Hot-wire Anemometry

Capsule endoscopy of the future: What's on the horizon?

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World Journal of gastroenterology 2015年第37期21卷 10528-10541页

作者： Piotr R Slawinski Keith L Obstein pietro Valdastri STORM Lab Department of Mechanical Engineering Vanderbilt University Division of gastroenterology Hepatology and Nutrition Vanderbilt University Medical Center

Capsule endoscopes have evolved from passively moving diagnostic devices to actively moving systems with potential therapeutic capability. In this review,we will discuss the state of the art, define the current shortcomings of capsule endoscopy, and address research areas that aim to overcome said *** in capsule mobility schemes are emphasized in this text, with magnetic actuation being the most promising endeavor. Research groups are working to integrate sensor data and fuse it with robotic control to outperform today's standard invasive procedures, but in a less intrusive manner. With recent advances in areas such as mobility, drug.delivery, and therapeutics, we foresee a translation of interventional capsule technology from the bench-top to the clinical setting within the next 10 years.

关键词： Capsule endoscopy Capsule robot mobility Diagnosti

Autoimmune liver serology:Current diagnostic and clinical challenges

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World Journal of gastroenterology 2008年第21期14卷 3374-3387页

作者： Dimitrios P Bogdanos Diego Vergani pietro Invernizzi Ian R Mackay Institute of Liver Studies King's College London School of Medicine at King's College HospitalDenmark Hill CampusLondon SE5 9RSUnited Kingdom Institute of Liver Studies King’s College London School of Medicine at King’s College HospitalDenmark Hill CampusLondon SE5 9RSUnited Kingdom Division of Internal Medicine and Liver Unit San Paolo Hospital School of MedicineUniversity of Mi-lanMilan 20142Italy department of Biochemistry and Molecular Bi-ology Monash UniversityClaytonVictoria 3800Australia

Liver-related autoantibodies are crucial for the correct diagnosis and classification of autoimmune liver diseas-es(AiLD),namely autoimmune hepatitis types 1 and 2(AIH-1 and 2),primary biliary cirrhosis(PBC),and the sclerosing cholangitis variants in adults and ***-1 is specified by anti-nuclear antibody(ANA) and smooth muscle antibody(SMA).AIH-2 is specified by antibody to liver kidney microsomal antigen type-1(anti-LKM1) and anti-liver cytosol type 1(anti-LC1).SMA,ANA and anti-LKM antibodies can be present in de-novo AIH following liver *** is specified by antimitochondrial antibodies(AMA) react-ing with enzymes of the 2-oxo-acid dehydrogenase complexes(chiefly pyruvate dehydrogenase complex E2 subunit) and disease-specific ANA mainly react-ing with nuclear pore gp210 and nuclear body *** cholangitis presents as at least two variants,first the classical primary sclerosing cholangitis(PSC) mostly affecting adult men wherein the only(and non-specific) reactivity is an atypical perinuclear antineutro-phil cytoplasmic antibody(p-ANCA),also termed peri-nuclear anti-neutrophil nuclear antibodies(p-ANNA) and second the childhood disease called autoimmune sclerosing cholangitis(ASC) with serological features resembling those of type 1 *** diagnostic serol-ogy is a fast-expanding area of investigation as new purified and recombinant autoantigens,and automatedtechnologies such as ELISAs and bead assays,become available to complement(or even compete with) tradi-tional immunofluorescence *** survey for the first time global trends in quality assurance impact-ing as it does on(1) manufacturers/purveyors of kits and reagents,(2) diagnostic service laboratories that fulfill clinicians' requirements,and(3) the end-user,the physician providing patient care,who must properly interpret test results in the overall clinical context.

关键词： Autoantigen Autoimmune hepatitis Auto-antibody Primary biliary cirrhosis Primary sclerosing cholangitis Liver disease

Modeling the transmission of Buruli ulcer in fluctuating environments

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International Journal of Biomathematics 2017年第5期10卷 45-67页

作者： Belthasara Assan Farai Nyabadza pietro Landi Cang Hui department of Mathematical Sciences Stellenbosch University Private Bag X1 Matieland Cape Town 7602 South Africa African Institute for Mathematical Sciences (AIMS) Cape Town 7945 South Africa

The transmission dynamics of Buruli ulcer （BU） largely depends on environmental changes. In this paper a deterministic model for the transmission of BU in fluctuating environments is proposed. The model incorporates periodicity in the disease transmission pathways and the Mycobacterium ulcerans density that are thought to vary seasonally. Two reproduction numbers, the time-averaged reproduction number [R0l and the basic reproduction number R0, are determined and compared. It is shown that the time-averaged reproduction underestimates the number of infections. Numerical simulations confirmed that if R0 〉 1 the infection is sustained seasonally. The model outcome suggests that environmental fluctuations should be taken into consideration in designing policies aimed at BU control and management.

关键词： Buruli ulcer time-averaged reproduction number basic reproduction number extinction persistence.

Association between hepatocellular carcinoma and type 2 diabetes mellitus in Italy:Potential role of insulin

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World Journal of gastroenterology 2008年第37期14卷 5695-5700页

作者： Valter Donadon Massimiliano Balbi pietro Casarin Alessandro Vario Alfredo Alberti department of Medicine and Internal Medicine 3rd Pordenone HospitalPordenone 33170 Italy department of Clinical and Experimental Medicine University of PadovaPadova 35100 Italy

AIM: To investigate the relationships between Type 2 diabetes mellitus (DM2) and the risk of hepatocellular carcinoma (HCC). METHODS: We studied the association between DM2 and HCC in a large case-control study that enrolled 465 consecutive Caucasian patients with HCC (78.3% males, mean age 68.5 ± 8.9 years) compared with an age and sex matched control group of 490 subjects. RESULTS: Prevalence of DM2 was significantly higher in HCC patients (31.2% vs 12.7%; OR = 3.12, 95% CI: 2.22-4.43) and in HCC cases with alcohol abuse. DM2 has been diagnosed before the appearance of HCC in 84.1% of diabetic HCC subjects with mean duration of 141.5 mo, higher in cases treated with insulin than in those with oral antidiabetic agents (171.5 vs 118.7 mo). Compared to controls, males DM2 with HCC were more frequently treated with insulin (38.1% vs 17.6%, P = 0.009) and with sulfonylurea with or without metformin than with diet with or without metformin (84% vs 68.3%, P = 0.049). CONCLUSION: DM2 in our patients is associated with a 3-fold increase risk of HCC. In most of our cases DM2 pre-existed to HCC. Patients with DM2 and chronic liver disease, particularly insulin treated males, should be considered for HCC close surveillance programs.

关键词： Hepatocellular carcinoma Type 2 diabetesmellitus Hepatitis virus B and C Insulin Antidiabetic therapy

A novel approach for manufacturing of layered,ultra-refractory composites using pliable,short fibre-reinforced ceramic sheets

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Journal of Advanced Ceramics 2023年第1期12卷 155-168页

作者： Matteo MOR Antonio VINCI Simone FAILLA pietro gALIZIA Luca ZOLI Diletta SCITI ISSMC-CNR Institute of ScienceTechnology and Sustainability for CeramicsVia Granarolo 6448018 Faenza(RA)Italy

A new additive technique for manufacturing of short fibre-reinforced ultra-refractory ceramics is *** technique allows the fabrication of solvent-free,thin(~100µm),flexible,and easy-to-handle sheets suitable for fabricating homogeneous or layered structures.A large range of compositions,in terms of matrix and fibre volumetric contents,from 0%to 100%is *** amount of short carbon fibres incorporated in the sheets ranged from 20 to 50 vol%,whereas the fibre length ranged from 3 to 5 *** matrix composition investigated with this technique consisted of ZrB_(2)/SiC/Y_(2)O_(3).By increasing the fibre amount from 35 to 50 vol%,an improvement of mechanical properties was ***-point flexural strength(σ)ranged from 107 to 140 MPa,depending on the amount of carbon fibres(Cf).The same holds true for the work of fracture,ranging from 108 to 253 J/m^(2).Functionally graded composites were fabricated by overlapping sheets with a fibre gradient(0%-50%).

关键词： ultra-high-temperature ceramics(UHTCs) ceramic matrix composites(CMCs) short carbon fibres mechanical properties

A time fractional model to represent rainfall process

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Water Science and Engineering 2014年第1期7卷 32-40页

作者： Jacques gOLdeR Maminirina JOELSON Marie-Christine NEEL Liliana DI pietro department of Physics University of Avignon Mediterranean Environment and Agro-Hydro System Modelisation Laboratory French National Institute for Agricultural Research

This paper deals with a stochastic representation of the rainfall process. The analysis of a rainfall time series shows that cumulative representation of a rainfall time series can be modeled as a non-gaussian random walk with a log-normal jump distribution and a time-waiting distribution following a tempered a-stable probability law. Based on the random walk model, a fractional Fokker-Planck equation （FFPE） with tempered a-stable waiting times was obtained. Through the comparison of observed data and simulated results from the random walk model and FFPE model with tempered a-stable waiting times, it can be concluded that the behavior of the rainfall process is globally reproduced, and the FFPE model with tempered a-stable waiting times is more efficient in reproducing the observed behavior.

关键词： rainfall process heavy-tailed probability distribution tempered a-stable probability law log-normal law Hurst exponent continuous time random walk model fractional Fokker-Planck equation