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Weighted‑indexed semi‑Markov model:calibration and application to financial modeling

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Financial Innovation 2023年第1期9卷 916-931页

作者： riccardo De Blasis Department of Management Marche Polytechnic UniversityAnconaItaly

We address the calibration issues of the weighted-indexed semi-Markov chain(WISMC)model applied to high-frequency financial ***,we propose to automate the discretization of the price returns and the volatility index by using four different approaches,two based on statistical quantities,namely,the quantile and sigma discretization,and two derived by the application of two popular machine learning algorithms,namely the k-means and Gaussian mixture model(GMM).Moreover,by comparing the Bayesian information criterion(BIC)scores,the GMM approach allows for the selection of the number of states of returns and *** application to Bitcoin prices at 1-min and 1-s intervals shows the validity and usefulness of the proposed discretization *** particular,GMM discretization is well suited for highfrequency returns,whereas the quantile approach works better for low-frequency ***,by comparing the results of the Monte Carlo simulation,we show that the WISMC model,applied with the proposed discretization,can reproduce the longrange serial correlation of the squared returns,which is typical of the financial markets and,in particular,the cryptocurrency market.

关键词： Semi-Markov WISMC Bitcoin EWMA k-means GMM

Cretaceous alkaline volcanism in south Marzanabad,northern central Alborz,Iran:Geochemistry and petrogenesis

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Geoscience Frontiers 2016年第6期7卷 937-951页

作者： Roghieh Doroozi Carmela Vaccaro Fariborz Masoudi riccardo Petrini Faculty of Earth Science Shahid Beheshti UniversityVelenjakTehranlran Department of Mineralogy University of FerraraCorso Ercole I d'Este 3244100 FerraraItaly Department of Mathematics and Geosciences University of TriesteVia Weiss8-34100 TriesteItaly

The alkali-basalt and basaltic trachy-andesites volcanic rocks of south Marzanabad were erupted during Cretaceous in central Alborz, which is regarded as the northern part of the Alpine-Himalayan orogenic belt. Based on petrography and geochemistry, en route fractional crystallization of ascending magma was an important process in the evolution of the volcanic rocks. Geochemical characteristics imply that the south Marzanabad alkaline basaltic magma was originated from the asthenospheric mantle source, whereas the high ratios of （La/Yb）N and （Dy/Yb）N are related to the low degree of partial melting from the garnet bearing mantle source. Enrichment pattern of Nb and depletion of Rb, K and Y, are similar to the OIB pattern and intraplate alkaline magmatic rocks. The K/Nb and Zr/Nb ratios of volcanic rocks range from 62 to 588 and from 4.27 to 9 respectively, that are some higher in more evolved samples which may reflect minor crustal contamination. The isotopic ratios of Sr and Nd respectively vary from 0.70370 to 0.704387 and from 0.51266 to 0.51281 that suggest the depleted mantle as a magma source. The development of south Marzanabad volcanic rocks could be related to the presence of extensional phase, upwelling and decompressional melting of asthenospheric mantle in the rift basin which made the alkaline magmatism in Cretaceous, in northern central Alborz of lran.

关键词： Volcanic rocks Cretaceous Marzanabad Central Alborz Iran

One or two things Restoration works about architecture： at Trajan＇s Market

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Frontiers of Architectural Research 2015年第2期4卷 81-90页

作者： riccardo d'Aquino1 33 via Guido Reni 00196 Rome Italy

One of the objectives of the redevelopment project for Trajan＇s Market, which spanned from 2000 to 2002, was to rearrange the market＇s accessibility and the visiting paths that connect and cross the entire site. The purpose was to extensively expose its beauty and thus invite more tounsts into the area. The project design consisted of a series of catwalks placed at different levels and was conceived with respect to three criteria：（1） the didactic significance of forms and materials; （2） the coherence between architectural forms, techniques, and matenals with the identity of the place; and （3） the possibility of removing, if necessary, newly added elements without damaging the relics. The project also involved the rearrangement and reconstruction of the former ＂Giardino delle Mitizie＂（2002-2007） to allow public access to the archaeological stratification and to the ancient Roman street located at its bottom. Consequently, the vaults of the convent were suspended upon a system of steel beams, which, together with several wooden pillars, also support the glass roof of the space, offering a close view of the ancient Roman walls. The structure and architectural forms coincide, implying that each of these elements is necessary and genuine.

关键词： Conservation Charters Place Patimpsest .Heritage Trajan's Market

Compressing deep-quaternion neural networks with targeted regularisation

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CAAI Transactions on Intelligence Technology 2020年第3期5卷 172-176页

作者： riccardo Vecchi Simone Scardapane Danilo Comminiello Aurelio Uncini Department of Information Engineering Electronics and Telecommunications(DIET)‘Sapienza’University of RomeRoma Lazio 00185Italy

In recent years,hyper-complex deep networks(such as complex-valued and quaternion-valued neural networks–QVNNs)have received a renewed interest in the *** find applications in multiple fields,ranging from image reconstruction to 3D audio *** to their real-valued counterparts,quaternion neural networks require custom regularisation strategies to avoid *** addition,for many real-world applications and embedded implementations,there is the need of designing sufficiently compact networks,with few weights and ***,the problem of regularising and/or sparsifying QVNNs has not been properly addressed in the literature as of *** this study,the authors show how to address both problems by designing targeted regularisation strategies,which can minimise the number of connections and neurons of the network during *** this end,they investigate two extensions of ℓ1 and structured regularisations to the quaternion *** the authors’experimental evaluation,they show that these tailored strategies significantly outperform classical(realvalued)regularisation approaches,resulting in small networks especially suitable for low-power and real-time applications.

关键词： networks neural valued

Radiological findings in non-surgical recurrent hepatocellular carcinoma:From locoregional treatments to immunotherapy

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World Journal of Gastroenterology 2023年第11期29卷 1669-1684页

作者： Davide Ippolito Cesare Maino Marco Gatti Paolo Marra riccardo Faletti Francesco Cortese riccardo Inchingolo Sandro Sironi Department of Radiology IRCCS San Gerardo dei TintoriMonza 20900Italy School of Medicine and Surgery University of Milano-BicoccaMilano 20121Italy Department of Surgical Sciences University of TurinTurin 10126Italy Department of Diagnostic and Interventional Radiology Papa Giovanni ⅩⅩⅢ HospitalBergamo 24127Italy Interventional Radiology Unit “F.Miulli”Regional General HospitalBari 70121Italy

Since hepatocellular carcinoma(HCC)represents an important cause of mortality and morbidity all over the ***,it is fundamental not only to achieve a curative treatment but also to manage in the best way any possible *** if the latest update of the Barcelona Clinic Liver Cancer guidelines for HCC treatment has introduced new locoregional techniques and confirmed others as well-established clinical practices,there is still no consensus about the treatment of recurrent HCC(RHCC).Locoregional treatments and medical therapy represent two of the most widely accepted approaches for disease control,especially in the advanced stage of liver *** medical treatments are now approved,and others are under *** this basis,radiology plays a central role in the diagnosis of RHCC and the assessment of response to locoregional treatments and medical therapy for *** review summarized the actual clinical practice by underlining the importance of the radiological approach both in the diagnosis and treatment of RHCC.

关键词： Carcinoma Hepatocellular Liver Ablation Catheter Radio frequency ablation Ablation techniques Medication therapy management RECIST

Negative capsule endoscopy in patients with obscure gastrointestinal bleeding reliable: Recurrence of bleeding on long-term follow-up

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World Journal of Gastroenterology 2013年第28期19卷 4520-4525页

作者： Maria Elena Riccioni riccardo Urgesi Rossella Cianci Gianluca Rizzo Luca D'Angelo riccardo Marmo Guido Costamagna Digestive Endoscopy Unit Catholic University of Rome 00168 Rome Italy Gastroenterology and Digestive Endoscopy Unit Ospedale Belcolle 01100 Viterbo Italy Department of Internal Medicine Catholic University of Rome 00168 Rome Italy Department of Surgery Catholic University of Rome 00168 Rome Italy Department of Neurosurgery Ospedale Belcolle 01100 Viterbo Italy Gastroenterology Unit Ospedale di Polla 84035 Polla Salerno Italy

AIM: To assess the rate of recurrent bleeding of the small bowel in patients with obscure bleeding already undergone capsule endoscopy (CE) with negative results. METHODS: We reviewed the medical records related to 696 consecutive CE performed from December 2002 to January 2011, focusing our attention on patients with recurrence of obscure bleeding and negative CE. Evaluating the patient follow-up, we analyzed the recurrence rate of obscure bleeding in patient with a negative CE. Actuarial rates of rebleeding during follow-up were calculated, and factors associated with rebleeding were assessed through an univariate and multivariate analysis. A P value of less than 0.05 was regarded as statistically significant. The sensitivity, specificity, and positive and negative predictive values (PPV and NPV) of negative CE were calculated. RESULTS: Two hundred and seven out of 696 (29.7%) CE studies resulted negative in patient with obscure/overt gastrointestinal bleeding. Overall, 489 CE (70.2%) were positive studies. The median follow-up was 24 mo (range 12-36 mo). During follow-up, recurrence of obscure bleeding was observed only in 34 out of 207 negative CE patients (16.4%); 26 out of 34 with obscure overt bleeding and 8 out of 34 with obscure occult bleeding. The younger age (< 65 years) and the onset of bleeding such as melena are independent risk factors of rebleeding after a negative CE (OR = 2.6703, 95%CI: 1.1651-6.1202, P = 0.0203; OR 4.7718, 95%CI: 1.9739-11.5350, P = 0.0005). The rebleeding rate (CE+ vs CE-) was 16.4% vs 45.1% (χ 2 test, P = 0.00001). The sensitivity, specificity, and PPV and NPV were 93.8%, 100%, 100%, 80.1%, respectively. CONCLUSION: Patients with obscure gastrointestinal bleeding and negative CE had a significantly lower rebleeding rate, and further invasive investigations can be deferred.

关键词： Capsule endoscopy Enteroscopy Anemia Obscure gastrointestinal bleeding Rebleeding

Percutaneous insertion of a novel dedicated metal stent to treat malignant hilar biliary obstruction

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World Journal of Gastrointestinal Oncology 2022年第9期14卷 1833-1843页

作者： Francesco Cortese Fabrizio Acquafredda Andrea Mardighian Maria Teresa Zurlo Valentina Ferraro riccardo Memeo Stavros Spiliopoulos riccardo Inchingolo Interventional Radiology Unit Miulli HospitalAcquaviva Delle Fonti 70124Italy Unit of Hepatobiliary Surgery Miulli hospitalAcquaviva Delle Fonti 70124Italy 2nd Radiology Department National and Kapodistrian University of AthensChaidari Athens 12461Greece

BACKGROUND Percutaneous bilateral biliary stenting is an established method for the management of unresectable malignant hilar biliary *** To evaluate the efficacy and safety of a novel uncovered biliary stent, specifically designed for hilar *** This, single-center, retrospective study included 18 patients(mean age 71 ± 11 years;61.1% male) undergoing percutaneous transhepatic Moving cell stent(MCS) placement for hilar reconstruction using the stent-in-stent technique for malignant biliary strictures, between November 2020 and July 2021. The Patients were diagnosed with cholangiocarcinoma(12/18;66.6%), gallbladder cancer(5/18;27.7%), and colorectal liver metastasis(1/18;5.5%). Primary endpoints were technical(appropriate stent placement) and clinical(relief from jaundice) success. Secondary endpoints included stent patency, overall survival, complication rates and stent-related *** The technical and clinical success rates were 100%(18/18 cases). According to Kaplan-Meier analysis, the estimated overall patient survival was 80.5% and 60.4% at 6 and 12 mo respectively, while stent patency was 90.9% and 68.2% at 6 mo and 12 mo respectively. The mean stent patency was 172.53 ± 56.20 d and median stent patency was 165 d(range 83-315). Laboratory tests for cholestasis significantly improved after procedure: mean total bilirubin decreased from 15.2 ± 6.0 mg/d L to 1.3 ± 0.4 mg/d L(P < 0.001);mean γGT decreased from 1389 ± 832 U/L to 114.6 ± 53.5 U/L(P < 0.001). One periprocedural complication was reported. Stent-related complications were observed in 5 patients(27.7%), including 1 occlusion(5.5%) and 1 stent migration(5.5 %).CONCLUSION Percutaneous hilar bifurcation biliary stenting with the MCS resulted in excellent clinical and technical success rates, with acceptable complication rates. Further studies are needed to confirm these initial positive results.

关键词： Malignant hilar biliary obstructions Hilar cholangiocarcinoma Self-expandable metallic stent Stent-in-stent technique Percutaneous approach Bilateral Y-stenting

Updates on larynx cancer epidemiology

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Chinese Journal of Cancer Research 2020年第1期32卷 18-25页

作者： riccardo Nocini Gabriele Molteni Camilla Mattiuzzi Giuseppe Lippi Section of Ear Nose and Throat(ENT) Department of Surgical SciencesDentistryGynecology and PediatricsUniversity of VeronaVerona 37134Italy Service of Clinical Governance Provincial Agency for Social and Sanitary ServicesTrento 38123Italy Section of Clinical Biochemistry Department of NeuroscienceBiomedicine and MovementUniversity of VeronaVerona 37134Italy

Objective: Laryngeal cancer is an important oncologic entity, whose prognosis depends on establishing appropriate preventive and diagnostic measures, especially in populations at higher ***: Epidemiologic information including worldwide incidence, prevalence, burden of health loss(disability-adjusted life year;DALYs) and mortality of larynx cancer was obtained from the Global Health Data Exchange(GHDx) ***: The current incidence, prevalence and mortality of laryngeal cancer are estimated at 2.76 cases/year per 100,000 inhabitants, 14.33 cases/year per 100,000 inhabitants and 1.66 deaths/year per 100,000 inhabitants,respectively, averaging 3.28 million DALYs each year. Incidence and prevalence have increased by 12% and 24%,respectively during the past 3 decades, whilst mortality has declined by around 5%. The epidemiologic burden of this malignancy is approximately 5-fold higher in males and increases in parallel with ageing, peaking after 65 years of age. Both incidence and mortality rates are higher in Europe and lower in Africa, but the ratio between deaths and incidence is the highest in Africa. Incidence has gradually declined in Europe during the past 3 decades, whilst it has increased in South-East Asia and Western Pacific. Cigarette smoking and alcohol abuse contribute for about 90% of overall worldwide mortality for laryngeal ***: Laryngeal cancer still poses a high clinical and societal burden, with an escalating temporal trend not expected to reverse soon.

关键词： Larynx laryngeal cancer larynx cancer epidemiology mortality

Selective internal radiation therapy segmentectomy:A new minimally invasive curative option for primary liver malignancies?

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World Journal of Gastroenterology 2024年第18期30卷 2379-2386页

作者： riccardo Inchingolo Francesco Cortese Antonio Rosario Pisani Fabrizio Acquafredda Roberto Calbi riccardo Memeo Fotis Anagnostopoulos Stavros Spiliopoulos Unit of Interventional Radiology “F.Miulli”Regional General HospitalBari 70021Italy Interdisciplinary Department of Medicine Section of Nuclear MedicineUniversity of Bari“Aldo Moro”Bari 70121Italy Department of Radiology General Regional Hospital“F.Miulli”Acquaviva delle Fonti 70021Italy Unit of Hepato-Pancreatic-Biliary Surgery “F.Miulli”Regional General HospitalBari 70021Italy The Second Radiology Department National and Kapodistrian University of AthensChaidari Athens 12461Greece

Transarterial radioembolization or selective internal radiation therapy(SIRT)has emerged as a minimally invasive approach for the treatment of *** percutaneous technique involves the local,intra-arterial delivery of radioactive microspheres directly into the *** employed as a palliative measure for liver malignancies,SIRT has gained traction over the past decade as a potential curative option,mirroring the increasing role of radiation *** latest update of the BCLC hepatocellular carcinoma guidelines recognizes SIRT as an effective treatment modality comparable to other local ablative methods,particularly well-suited for patients where surgical resection or ablation is not *** segmentectomy is a more selective approach,aiming to deliver high-dose radiation to one to three specific hepatic segments,while minimizing damage to surrounding healthy *** research efforts in radiation segmentectomy should prioritize optimizing radiation dosimetry and refining the technique for super-selective administration of radiospheres within the designated hepatic segments.

关键词： Transarterial radioembolization Selective internal radiation therapy Radiation segmentectomy Hepatocellular carcinoma Primary liver malignancies Personalised dosimetry