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A Theory of the Risk for Empirical CVaR with Application to Portfolio Selection

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Journal of Systems Science & Complexity 2021年第5期34卷 1879-1894页

作者： ARICI Giorgio CAMPI marco C. CARE Algo DALAI marco RAMPONI Federico A. Department of Information Engineering University of Bresciavia Branze 3825123 BresciaItaly.

When decisions are based on empirical observations,a trade-off arises between flexibility of the decision and ability to generalize to new *** this paper,we focus on decisions that are obtained by the empirical minimization of the Conditional Value-at-Risk(CVa R)and argue that in CVa R the trade-off between flexibility and generalization can be understood on the ground of theoretical results under very general assumptions on the system that generates the *** results have implications on topics related to order and structure selection in various applications where the CVa R risk-measure is used.A study on a portfolio optimization problem with real data demonstrates our results.

关键词： Distribution-free results empirical CVa R generalization order selection risk scenario approach

High-dimensional neural network potentials for magnetic systems using spin-dependent atom-centered symmetry functions

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npj Computational Materials 2021年第1期7卷 1541-1551页

作者： marco Eckhoff Jörg Behler Universität Göttingen Institut für Physikalische ChemieTheoretische ChemieTammannstrasse 637077 GöttingenGermany Universität Göttingen International Center for Advanced Studies of Energy Conversion(ICASEC)Tammannstrasse 637077 GöttingenGermany

Machine learning potentials have emerged as a powerful tool to extend the time and length scales of first-principles quality ***,most machine learning potentials cannot distinguish different electronic spin arrangements and thus are not applicable to materials in different magnetic *** we propose spin-dependent atom-centered symmetry functions as a type of descriptor taking the atomic spin degrees of freedom into *** used as an input for a high-dimensional neural network potential(HDNNP),accurate potential energy surfaces of multicomponent systems can be constructed,describing multiple collinear magnetic *** demonstrate the performance of these magnetic HDNNPs for the case of manganese oxide,*** method predicts the magnetically distorted rhombohedral structure in excellent agreement with density functional theory and *** efficiency allows to determine the Néel temperature considering structural fluctuations,entropic effects,and *** method is general and is expected to be useful also for other types of systems such as oligonuclear transition metal complexes.

关键词： magnetic symmetry neural

On some examples of obstructed irregular surfaces

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Science China Mathematics 2011年第8期54卷 1713-1724页

作者： MANETTI marco Dipartimento di Matematica "Guido Castelnuovo" Universita degli studi di Roma La SapienzaRoma I-00185Italy

We determine the base space of the Kuranishi family of some complete intersections in the product of an abelian variety and a projective *** a consequence,we obtain new examples of obstructed irregular surfaces with a... 详细信息

关键词： algebraic surfaces deformation theory Kuranishi family

Taxonomical notes on selected freshwater fish species described from northern and central Vietnam （Cypriniformes： Balitoridae, Cobitidae, Cyprinidae, Nemacheilidae; Perciformes： Channidae, Osphronemidae; Synbranchiformes： Mastacembelidae）

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Zoological Research 2014年第2期35卷 142-159页

作者： marco Endruweit Qingshan Road 601 Qingdao China

Selected,little known taxa of northern and central Vietnamese freshwater fish species are *** acts are taken:Hemibarbus lehoai is placed in synonymy of ***,Paracobitis hagiangensis in synonymy of Schistura caudofurca.A neotype of Micronemacheilus bacmeensis is *** name Channa hanamensis is treated as a nomen *** labeonine species described from China are nomenclaturally affected:Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition;the specific epithet of Sinigarra napoense is corrected to napoensis.

关键词： New species Ichthyology Taxonomy Nomenclature Vietnam

Schistura megalodon species nova, a new river loach from the Irrawaddy basin in Dehong, Yunnan, China （Teleostei： Cypriniformes： Nemacheilidae）

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Zoological Research 2014年第5期35卷 353-361页

作者： marco Endruweit 601 Qingshan Road Licang Qingdao Shandong Qingdao 266001 China

A new species of river loach, Schistura megalodon sp. nov., is described from the Irrawaddy basin in Yingjiang County, Dehong Autonomous Prefecture, Yuunan Province, China. The following combination of diagnostic characters serve to distinguish it from all other congeners in the given zoogeographical region： a large processus dentiformes in the upper jaw, a short pre-anus length of 65.4%-66.3% of SL, long paired fins （pectoral： 20.8%-24.2% of SL; pelvic： 17.9%-20.6% of SL）, a wide body of 9.7%-11.3% of SL at anal fin origin, an incomplete lateral line, the absence of an orbital lobe, and a broad and distinct basicaudal bar with forward extensions.

关键词： Schistura megalodon Irrawaddy Dehong Yunnan

The association of type and number of high-risk criteria with cancer-specific mortality in prostate cancer patients treated with radical prostatectomy

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Current Urology 2024年第2期18卷 128-132页

作者： Francesco Chierigo Rocco Simone Flammia GabrieleSorce Benedikt Hoeh Lukas Hohenhorst Andrea Panunzio Zhe Tian Fred Saad Marcus Graefen Michele Gallucci Alberto Briganti Francesco Montorsi Felix K.H.Chun Shahrokh F.Shariat Alessandro Antonelli Giovanni Guano Guglielmo Mantica marco Borghesi Nazareno Suardi Carlo Terrone Pierre I.Karakiewicz Department of Surgical and Diagnostic Integrated Sciences University of GenovaGenovaItaly IRCCS Ospedale Policlinico San Martino GenovaItaly Cancer Prognostics and Health Outcomes Unit Division of UrologyUniversity ofMontréal Health CenterMontréalQuébecCanada Department of Urology IRCCS Policlinico San MartinoGenovaItaly Department of Maternal-Child and Urological Sciences Sapienza Rome UniversityPoliclinico Umberto I HospitalRomeItaly Department of Urology University Hospital FrankfurtFrankfurt am MainGermany Martini-Klinik Prostate Cancer Center University Hospital Hamburg-EppendorfHamburgGermany Department of Urology University of VeronaAzienda Ospedaliera Universitaria Integrata di VeronaVeronaItaly Division of Experimental Oncology/Unit of Urology URIUrological Research InstituteIRCCS San Raffaele Scientific InstituteMilanItaly Department of Urology Comprehensive Cancer CenterMedical University of ViennaViennaAustria Department of Urology Weill Cornell Medical CollegeNew YorkNYUSA Department of Urology University of Texas SouthwesternDallasTXUSA Department of Urology Second Faculty of MedicineCharles UniversityPragueCzech Republic Institute for Urology and Reproductive Health I.M.Sechenov First Moscow State Medical UniversityMoscowRussia Division of Urology Department of Special SurgeryJordan University HospitalThe University of JordanAmmanJordan

Objectives:This study aimed to test the association between of type and number of D'Amico high-risk criteria(DHRCs)with cancer-specific mortality(CSM)in high-risk prostate cancer patients treated with radical *** and methods:In the Surveillance,Epidemiology,and End Results database(2004–2016),we identified 31,281 radical prostatectomy patients with at least 1 DHRC,namely,prostate-specific antigen(PSA)>20 ng/mL(hrPSA),biopsy Gleason Grade Group(hrGGG)score of 4 and 5,or clinical tumor stage≥T3(hrcT).Multivariable Cox regression models and competing risks regression models(adjusting for other cause mortality)tested the association between DHRCs and 5-year ***:Of 31,281 patients,14,394(67%)exclusively harbored hrGGG,3189(15%)harbored hrPSA,and 1781(8.2%)harbored *** 2132 patients(6.8%)harbored a combination of the 2 DHRCs,and 138(0.6%)had all 3 ***-year CSMrates ranged from 0.9%to 3.0%when any individual DHRC was present(hrcT,hrPSA,and hrGGG,in that order),1.6%to 5.9%when 2 DHRCs were present(hrPSA-hrcT,hrcT-hrGGG,and hrPSA-hrGGG,in that order),and 8.1%when all 3 DHRCs were *** regression models and competing risks regression confirmed the independent predictor status of DHRCs for 5-year CSM that was observed in univariable analyses,with hazard ratios from 1.00 to 2.83 for 1 DHRC,2.35 to 5.88 for combinations of 2 DHRCs,and 7.13 for all 3 ***:Within individual DHRCs,hrcT and hrPSA exhibited weaker effects than hrGGG ***,a dose-response effect was identified according to the number of ***,the type and number of DHRCs allow further risk stratification within the high-risk subgroup.

关键词： High risk prostate cancer Radical prostatectomy Cancer-specific mortality Staging SEER

Coal petrology analysis and implications in depositional environments from upper Cretaceous to Miocene:a study case in the Eastern Cordillera of Colombia

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International Journal of Coal Science & Technology 2021年第5期8卷 869-896页

作者： Clara Guatame marco Rincon Servicio Geologico Colombiano diagonal 53 n.°34-53BogotaColombia

The Piedemonte Llanero Basin is located on the eastern side of the Eastern Cordillera of the Colombian *** has been the subject of numerous geological studies carried out for the oil sector,*** study presents the coalpetrographical features of 15 coal seams of four geological formations from Late Cretaceous to Middle Miocene(Chipaque formation,Palmichal group,Arcillas del Limbo formation,and San Fernando formation).Analysis of 33 samples indicates enrichment in vitrinite,while liptinite and inertinite concentrations vary according to the stratigraphic *** indicates that the coal range gradually decreases from highly volatile bituminous C(Chipaque formation)to subbituminous C(San Fernando formation).The microlithotypes with the highest concentrations are clarite and *** composition and coal facies indicate changes in the depositional conditions of the *** precursor peat from Late Cretaceous to Late Paleocene accumulated under limnic conditions followed by telmatic in Late Eocene-Early *** coal facies indices show wet conditions in forest swamps with variations in the flooding surface,influxes of brackish water and good tissue *** tectonic conditions along the Piedemonte Llanero basin is evident,from post-rift to foreland basin,evidenced by oxic and anoxic periods reflected in the maceral composition and its *** coal environment corresponds to an estuarine system started in the Chipaque formation evolving to the lacustrine conditions in the San Fernando formation.

关键词： Eastern cordillera basin Northern Andes Coal Organic petrology

Impact of minimally invasive surgery on the treatment of benign esophageal disorders

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World Journal of Gastroenterology 2012年第46期18卷 6764-6770页

作者： Brian Bello Fernando A Herbella marco E Allaix marco G Patti Department of Surgery University of Chicago Pritzker School of Medicine

Thanks to the development of minimally invasive surgery, the last 20 years have witnessed a change in the treatment algorithm of benign esophageal disorders. Today a laparoscopic operation is the treatment of choice for esophageal achalasia and for most patients with gastroesophageal reflux disease. Because the pathogenesis of achalasia is unknown, treatment is palliative and aims to improve esophageal emptying by decreasing the functional obstruction at the level of the gastro-esophageal junction. The refinement of minimally invasive techniques accompanied by large, multiple randomized control trials with long-term outcome has allowed the laparoscopic Heller myotomy and partial fundoplication to become the treatment of choice for achalasia compared to endoscopic procedures, including endoscopic botulinum toxin injection and pneumatic dilatation. Patients with suspected gastroesophageal reflux need to undergo a thorough preoperative workup. After establishing diagnosis, treatment for gastroesophageal reflux should be individualized to patient characteristics and a decision about an operation made jointly between surgeon and patient. The indications for surgery have changed in the last twenty years. In the past, surgery was often considered for patients who did not respond well to acid reducing medications. Today, the best candidate for surgery is the patient who has excellent control of symptoms with proton pump inhibitors. The minimally invasive approach to antireflux surgery has allowed surgeons to control reflux in a safe manner, with excellent long term outcomes. Like achalasia and gastroesophageal reflux, the treatment of patients with paraesophageal hernias has also seen a major evolution. The laparoscopic approach has been shown to be safe, and durable, with good relief of symptoms over the long-term. The most significant controversy with laparoscopic paraesophageal hernia repair is the optimal crural repair. This manuscript reviews the evolution of these tec

关键词： Gastroesophageal reflux disease Esophageal achalasia Hiatal hernia Laparoscopic fundoplication Laparoscopic Heller myotomy

Inter- and intra-population variability of the protein content of femoral gland secretions from a lacertid lizard

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Current Zoology 2017年第6期63卷 657-665页

作者： marco MANGIACOTTI marco FUMAGALLI Stefano SCALI marco A.L. ZUFFI Maddalena CAGNONE Roberta SALVINI Roberto SACCHI Department of Earth and Environmental Sciences University of Pavia Via Taramelli 24 Pavia 1-27100 Italy Museo Civico di Storia Naturale di Milano Corso Venezia 55 Milano 1-20121 Italy Department of Biology and Biotechnology "L. Spallanzani" Biochemistry Unit University of Pavia Via Taramelli 3 Pavia 1-27100 Italy Museo di Storia Naturale Universita di Pisa Via Roma 79 Calci Pisa 1-56011 Italy Department of Molecular Medicine Biochemistry Unit University of Pavia Via Taramelli 3 Pavia 1-27100 Italy

Femoral glands of male lizards produce waxy secretions that are involved in inter- and intraspecific chemical communication. The main components of these secretions are proteins and lipids, the latter having been extensively studied and already associated to male quality. On the opposite, the composition and role of proteins are nearly unknown, the only available information coming from few studies on iguanids. These studies got the conclusion that proteins might have a communicative function, notably they could signal individual identity. A generalization of these findings requires the extension of protein analysis to other lizard families, and the primary detection of some patterns of individual variability. Using the common wall lizard Podarcis muralis as a model species, the protein fraction of the femoral pore secretions was investigated to provide the first characterization of this component in a lacertid lizard and to explore its source of variability, as a first step to support the hypothesized communicative role. Samples of proteins from femoral secretions were collected from 6 Italian populations and subjected to 1-dimensional electrophoresis. The binary vector of the band presence/absence was used to define the individual profiles. Protein fraction is found to have a structured pattern, with both an individual and a population component. Although the former supports the potential communicative role of proteins, the latter offers a double interpretation, phylogenetic or environmental, even though the phylogenetic effect seems more likely given the climatic resemblance of the considered sites. Further studies are necessary to shed light on both these issues.

关键词： chemical communication femoral glands lizards Podarcis muralis proteins SDS-PAGE.