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The star formation history of redshift z^2 galaxies:the role of the infrared prior

Research in Astronomy and Astrophysics 2014年第1期14卷 15-34页

作者： Lu-Lu Fan Andrea Lapi alessandro Bressan Mario Nonino Gianfranco de Zotti Luigi Danese Center for Astrophysics University of Science and Technology of China Key Laboratory for Research in Galaxies and Cosmology Chinese Academy of Sciences Astrophysics Sector SISSA Dip.Fisica Univ.‘Tor Vergata’Via Ricerca Scientifica 100133 Roma INAF-Osservatorio Astronomico di Trieste

We build a sample of 298 spectroscopically-confirmed galaxies at redshift z - 2, selected in the z850-band from the GOODS-MUSIC catalog. By utilizing the rest frame 8 p.m luminosity as a proxy of the star formation rate （SFR）, we check the accuracy of the standard SED-fitting technique, finding it is not accurate enough to provide reliable estimates of the physical parameters of galaxies. We then develop a new SED-fitting method that includes the IR luminosity as a prior and a generalized Calzetti law with a variable Rv. Then we exploit the new method to re-analyze our galaxy sample, and to robustly determine SFRs, stellar masses and ages. We find that there is a general trend of increasing attenuation with the SFR. Moreover, we find that the SFRs range between a few to 103 M~ yr-1, the masses from 109 to 4 ~ 1011 Mo, and the ages from a few tens of Myr to more than 1 Gyr. We discuss how individual age measurements of highly attenuated objects indicate that dust must have formed within a few tens of Myr and already been copious at 〈 100 Myr. In addition, we find that low luminosity galaxies harbor, on average, significantly older stellar populations and are also less massive than brighter ones; we discuss how these findings and the well known ＇downsizing＇ scenario are consistent in a framework where less massive galaxies form first, but their star formation lasts longer. Finally, we find that the near-IR attenuation is not scarce for luminous objects, contrary to what is customarily assumed; we discuss how this affects the interpretation of the observed M,/L ratios.

关键词： cosmology: observations- galaxies: evolution- galaxies: high redshift-- galaxies: stellar content -- dust extinction

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Autoimmune pancreatitis not otherwise specified(NOS): Clinical features and outcomes of the forgotten type

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Hepatobiliary & Pancreatic Diseases International 2019年第6期18卷 576-579页

作者： Nicolò de Pretis Filippo Vieceli alessandro Brandolese Lorenzo Brozzi Antonio Amodio Luca Frulloni Gastroenterology Unit Pancreas Center University of Verona

Background:Autoimmune pancreatitis(AIP)is a well-recognized fibroinflammatory disease of the *** the significant number of studies published on AIP type 1 and 2,no studies have been focused on AIP type not otherwise specified(NOS)and therefore very little is known about clinical features and long-term outcomes of these *** aim of this study was to investigate clinical and radiological features of AIP type ***:Patients classified as AIP type NOS at clinical onset included in our database prospectively maintained since 1995 were ***,clinical data were collected and ***:Forty-six patients were included in the *** clinical onset was mainly characterized by weight loss,jaundice and acute *** patients(17.4%)were reclassified as AIP type 2 during follow-up because of the development of ulcerative *** patients(15.2%)experienced relapse after steroid treatment but only one(2.2%)needed immunosuppressive drugs because of recurrent ***:AIP type NOS shares clinical features similar to AIP type 2 and a relevant proportion of patients was reclassified as AIP type 2 during follow-up because of the development of ulcerative *** risk of relapse is low but not irrelevant.

关键词： Autoimmune pancreatitis Not otherwise specified Outcome Follow-up Therapy

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Cytoreduction and hyperthermic intraperitoneal chemotherapy in the treatment of peritoneal carcinomatosis from pseudomixoma peritonei

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World Journal of Gastroenterology 2008年第44期14卷 6817-6823页

作者： Tommaso Cioppa Marco Vaira Camilla Bing Silvia D'Amico alessandro Bruscino Michele de Simone department of General and Oncological Surgery "San Giuseppe" Hospitalviale Boccaccio50053 EmpoliFlorenceItaly

AIM： To investigate the most important aspects of hyperthermic intraperitoneal chemotherapy （HIPEC） that has been accepted as the standard treatment for pseudomyxoma peritonei （PMP）, with special regard to morbidity, overall survival （OS） and disease free survival （DFS） over 10 years. METHODS： Fifty-three patients affected by PMP underwent cytoreduction （CCR） and HIPEC with a ＂semi-closed＂ abdomen technique in our institution. The peritonectomy procedure and completeness of CCR were classified according to Sugarbaker criteria. Preoperative evaluation always included thoracic and abdominal CT scan to stage peritoneal disease and exclude distant metastases. Fifty-one patients in our series were treated with a protocol based on administration of cisplatinum 100 mg/m^2 plus mitomycin C 16 mg/m^2, at a temperature of 41.5℃ for 60 min. Anastomoses were always performed at the end of HIPEC. The mean duration of surgery was 12 h including HIPEC. Continuous monitoring of hepatic and renal functions and hydroelectrolytic balance was performed in the postoperative period. RESULTS： Twenty-four patients presented with postoperative complications： surgical morbidity was observed in 16 patients and 6 patients were reoperated. All complications were successfully treated and no postoperative deaths were observed. Risk factors for postoperative morbidity were considered to be gender, age, body surface, duration of surgery,Peritoneal Cancer Index （PCI） and tumor residual value （CC score）. No statistically significant correlation was found during the multivariate analysis： only the CC score was statistically significant. The OS in our experience was 81.8%, with a DFS of 80% at 5 years and of 70% at 10 years. CONCLUSION： In our experience, even if HIPEC combined with cytoreductive surgery involves a high risk of morbidity, postoperative complications can be resolved favorably in most cases with correct patient selection and adequate postoperative care, thus minimizing mortality. The ass

关键词： Peritonectomy Pseudomyxoma peritonei Hyperthermic perfusion Hyperthermic intraperitoneal chemotherapy Peritoneal carcinomatosis Locoregional treatment

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Coulomb Friction Driving Brownian Motors

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Communications in Theoretical Physics 2014年第10期61卷 505-513页

作者： alessandro Manacorda Andrea Puglisi alessandro Sarracino Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly Istituto dei Sistemi Complessi - CNR and Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly Kavli Institute for Theoretical Physics China the Chinese Academy of Sciences Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600case courrier 121Université Paris 64Place Jussieu75255 Paris CedexFrance

We review a family of models recently introduced to describe Brownian motors under the influence of Coulomb friction, or more general non-linear friction laws. It is known that, if the heat bath is modeled as the usual Langevin equation(linear viscosity plus white noise), additional non-linear friction forces are not sufficient to break detailed balance, i.e. cannot produce a motor effect. We discuss two possibile mechanisms to elude this problem. A first possibility, exploited in several models inspired to recent experiments, is to replace the heat bath's white noise by a "collisional noise", that is the effect of random collisions with an external equilibrium gas of particles. A second possibility is enlarging the phase space, e.g. by adding an external potential which couples velocity to position, as in a Klein–Kramers equation. In both cases, non-linear friction becomes sufficient to achieve a non-equilibrium steady state and, in the presence of an even small spatial asymmetry, a motor effect is produced.

关键词： Brownian motors ratchet effect Coulomb friction

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A flexible multi-body model of a surface miner for analyzing the interaction between rock-cutting forces and chassis vibrations

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International Journal of Mining Science and Technology 2021年第3期31卷 365-375页

作者： alessandro Medolago Stefano Melzi Tesmec S.p.A. Grassobbio 24050Italy department of Mechanics Politecnico di MilanoMilano 20156Italy

The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface *** these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue *** events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic *** work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of *** this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's *** model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics.

关键词： Surface miner Flexible multi-body model Validation Cutting forces Chassis vibrations

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Improving wood volume predictions in dry tropical forest in the semi-arid Brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson B de LIMA Patrícia A B BARRETO-GARCIA alessandro de PAULA Jhuly E S PEREIRA Flávia F de CARVALHO Silvio H M GOMES department of Forest Engineering State University of AmapáMacapá68900070Brazil department of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volumetric variability of dry tropical forests in Brazil and the scarcity of studies on the subject show the need for the development of techniques that make it possible to obtain adequate and accurate wood volume *** this study,we analyzed a database of thinning trees from a forest management plan in the Contendas de SincoráNational Forest,southwestern Bahia State,*** data set included a total of 300 trees with a trunk diameter ranging from 5 to 52 ***,validation and statistical selection of four volumetric models were *** to the difference in height values for the same diameter and the low correlation between both variables,we do not suggest models which only use the diameter at breast height(DBH)variable as a predictor because they accommodate the largest estimation *** comparing the best single entry model(Hohenald-Krenn)with the Spurr model(best fit model),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike information criterion(AIC)and adjusted determination coefficient(R2 adj),which are poorer than the second best model(Schumacher-Hall).Regarding the minimum sample size,errors in estimation(root mean square error(RMSE)and bias)of the best model decrease as the sample size increases,especially when a larger number of trees with DBH≥15.0 cm are randomly *** sampling by diameter class produces smaller volume prediction errors than random sampling,especially when considering all *** summary,the Spurr and Schumacher-Hall models perform *** models suggest that the total variance explained in the estimates is not less than 95%,producing reliable forecasts of the total volume with *** estimates indicate that the bias around the average is not greater than 7%.Our results support the decision to use regression methods to build models and estimate their parameters,seeking stratification strategies in diameter classes for the sample trees.

关键词： volume modeling minimal sample size Caatinga Spurr model forest management

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Gastric endoscopic submucosal dissection in Western countries:Indications,applications,efficacy and training perspective

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World Journal of Gastrointestinal Surgery 2021年第10期13卷 1180-1189页

作者： Luca de Luca Massimiliano Di Berardino Benedetto Mangiavillano alessandro Repici Gastroenterology and Digestive Endoscopy Unit Riuniti Marche North HospitalPesaro 61121Italy Gastrointestinal Endoscopy Unit Humanitas-Mater DominiCastellanza 21053Italy Digestive Endoscopy Unit Humanitas Clinical and Research CenterHumanitas UniversityRozzano 20089Italy

Endoscopic submucosal dissection was introduced in Japan for the mini-invasive treatment of early gastric cancer,as part of national screening program considering high prevalence of disease in these *** technique allows en-bloc curative oncological excision and to obtain in a single step R0-resection,characterization,histological staging and potential cure of the tumor with a very high cost-benefit *** the years,Western endoscopists have adopted endoscopic submucosal dissection,achieving good rates of efficacy,long-term improved outcomes and safety,with low risk of local recurrence comparable to those obtained in Asian ***,according to some authors,the excellent outcomes from East country could not be representative of the Western *** epidemiological differences of early gastric cancer,scant volume data and limitations in training opportunities between Western and Eastern countries,European Society of Gastrointestinal Endoscopy have adopted Japanese guidelines and developed a European core curriculum for endoscopic submucosal dissection *** should be able to estimate the probability of performing a curative resection by considering the benefit/risk relationship case-by-case in order to implement a correct decision-making process.

关键词： Endoscopic submucosal dissection Western experience Early gastric cancer Curative oncological excision Long-term outcome Training perspective

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Efficiency in hydrocarbon degradation and biosurfactant production by Joostella sp.A8 when grown in pure culture and consortia

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Journal of Environmental Sciences 2018年第5期30卷 115-126页

作者： Carmen Rizzo alessandro Ciro Rappazzo Luigi Michaud Emilio de Domenico Carlos Rochera Antonio Camacho Angelina Lo Giudice department of Chemical BiologicalPharmaceutical and Environmental Sciences(ChiBioFarAm)University of MessinaViale Ferdinando Stagno d'Alcontres 3198166 MessinaItaly Institute for the Coastal Marine Environment National Research Council(IAMC-CNR)Spianata San Raineri 8698122 MessinaItaly Cavanilles Institute for Biodiversity and Evolutionary Biology University of ValenciaCarrer del Catedratic Jose Beltran Martinez 246980 PaternaValenciaSpain Regional Centre for Water Studies(CREA) University of Castilla-La ManchaC/Altagracia 5013071 Ciudad RealSpain

Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolated from hydrocarbon enrichment cultures made of polychaete homogenates. In pure cultures Joostella sp. A8 showed the highest stable emulsion percentage（78.33%）, hydrophobicity rate（62.67%）, and an optimal surface tension reduction during growth in mineral medium supplemented with diesel oil（reduction of about 12 mN/m）, thus proving to be highly competitive with Alcanivorax and Pseudomonas strains. During growth in pure culture different level of biodegradation were detected for Alcanivorax strain A53（52.7%）,Pseudomonas strain A6（38.2%） and Joostella strain A8（26.8%）. When growing in consortia,isolates achieved similar abundance values, with the best efficiency that was observed for the Joostella-Pseudomonas co-culture. Gas-chromatographic analysis revealed an increase in the biodegradation efficiency in co-cultures（about 90%）, suggesting that the contemporary action of different bacterial species could improve the process. Results were useful to compare the efficiencies of well-known biosurfactant producers（i.e. Pseudomonas and Alcanivorax representatives） with a still unknown biosurfactant producer, i.e. Joostella, and to confirm them as optimal biosurfactant-producing candidates.

关键词： Joostella Biosurfactants Co-cultures Hydrocarbon degradation Biodegradation efficiency

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Structure-activity relationship in Pd/CeO2 methane oxidation catalysts

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Chinese Journal of Catalysis 2020年第6期41卷 938-950页

作者： Sara Colussi Paolo Fornasiero alessandro Trovarelli Dipartimento Politecnico Universitàdi UdineUnitàdi Ricerca INSTM Udinevia del Cotonificio 10833100 UdineItaly Dipartimento di Scienze Chimiche e Farmaceutiche Unitàdi Ricerca di Trieste ICCOM-CNRINSTM TriesteUniversitàdi Triestevia L.Giorgieri134127 TriesteItaly

Palladium based catalysts are the most active for methane oxidation. The tuning of their composition, structure and morphology at macro and nanoscale can alter significantly their catalytic behavior and robustness with a strong impact on their overall performances. Among the several combinations of supports and promoters that have been utilized, Pd/CeO2 has attracted a great attention due to its activity and durability coupled with the unusually high degree of interaction between Pd/Pd O and the support. This allows the creation of specific structural arrangements which profoundly impact on methane activation characteristics. Here we want to review the latest findings in this area, and particularly to envisage how the control(when possible) of Pd-CeO2 interaction at nanoscale can help in designing more robust methane oxidation catalysts.

关键词： Palladium Ceria Methane catalytic oxidation Pd-ceria interaction Nanostructure

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Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

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World Journal of Radiology 2024年第5期16卷 115-127页

作者： Laura Maria Cacioppa Chiara Floridi Alessandra Bruno NicolòRossini Tommaso Valeri Alessandra Borgheresi Riccardo Inchingolo Francesco Cortese Giacomo Novelli alessandro Felicioli Mario Torresi Pietro Boscarato Letizia Ottaviani Andrea Giovagnoni Division of Interventional Radiology Department of Radiological SciencesUniversity Politecnica Delle MarcheAncona 60126Italy department of Clinical Special and Dental SciencesUniversity Politecnica Delle MarcheAncona 60126Italy Division of Radiology Department of Radiological SciencesUniversity Hospital"Azienda Ospedaliero Universitaria Delle Marche"Ancona 60126Italy Interventional Radiology Unit "F Miulli"Regional General HospitalAcquaviva delle Fonti 70021Italy department of Radiology IRCCS INRCAAncona 60126Italy

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed *** tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the *** To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic *** In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were ***-three(65.7%)patients underwent endoscopy before *** volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated *** rate was obtained from volume change between the two phases and standardised for unit *** were divided into two groups,according to the angiographic signs and their concordance with *** Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)*** no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

关键词： Gastrointestinal haemorrhage Computed tomography angiography Volumetric analysis Computer-assisted image interpretation Therapeutic embolization Transcatheter arterial embolization

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