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The Barone-Adesi Whaley Formula to Price American Options Revisited

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Applied Mathematics 2015年第2期6卷 382-402页

作者： Lorella Fatone Francesca mariani maria Cristina Recchioni Francesco Zirilli Dipartimento di Matematica e Informatica Universit&agrave di Camerino Camerino Italy Dipartimento di Scienze Economiche Universit&agrave degli Studi di Verona Verona Italy Dipartimento di Management Universit&agrave Politecnica delle Marche Ancona Italy Dipartimento di Matematica “G. Castelnuovo” Universit&agrave di Roma “La Sapienza” Roma Italy

This paper presents a method to solve the American option pricing problem in the Black Scholes framework that generalizes the Barone-Adesi, Whaley method [1]. An auxiliary parameter is introduced in the American option pricing problem. Power series expansions in this parameter of the option price and of the corresponding free boundary are derived. These series expansions have the Baroni-Adesi, Whaley solution of the American option pricing problem as zero-th order term. The coefficients of the option price series are explicit formulae. The partial sums of the free boundary series are determined solving numerically nonlinear equations that depend from the time variable as a parameter. Numerical experiments suggest that the series expansions derived are convergent. The evaluation of the truncated series expansions on a grid of values of the independent variables is easily parallelizable. The cost of computing the n-th order truncated series expansions is approximately proportional to n as n goes to infinity. The results obtained on a set of test problems with the first and second order approximations deduced from the previous series expansions outperform in accuracy and/or in computational cost the results obtained with several alternative methods to solve the American option pricing problem [1]-[3]. For example when we consider options with maturity time between three and ten years and positive cost of carrying parameter (i.e. when the continuous dividend yield is smaller than the risk free interest rate) the second order approximation of the free boundary obtained truncating the series expansions improves substantially the Barone-Adesi, Whaley free boundary [1]. The website: http://***/recchioni/finance/w20 contains material including animations, an interactive application and an app that helps the understanding of the paper. A general reference to the work of the authors and of their coauthors in mathematical finance is the website: http://***.u

关键词： American Option Pricing Perturbation Expansion

Polyethylene glycols: An effective strategy for limiting liver ischemia reperfusion injury

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World Journal of Gastroenterology 2016年第28期22卷 6501-6508页

作者： Gianfranco Pasut Arnau Panisello Emma Folch-Puy Alexandre Lopez Carlos Castro-Benítez maria Calvo Teresa Carbonell Agustín García-Gil RenéAdam Joan Roselló-Catafau Department of Pharmaceutical and Pharmacological University of Padova and Veneto Institute of Oncology IRCCS 35128 Padova Italy Experimental Pathology Department Institute of Biomedical Research of Barcelona 08036 Barcelona Spain Centre Hepatobiliaire AP-HP Hopital Paul Brousse Inserm U935 Universite Paris-Sud Villejuif 75008 Paris France unitat de Microscopia Optic Avancada CCiTUB Centre Cientifics i Tecnologics Faculty of Medicine University of Barcelona 08036 Barcelona Spain Physiology Department Faculty of Biology Universitat de Barcelona 08036 Barcelona Spain Hospital Clinico de Zaragoza 50009 Zaragoza Spain

Liver ischemia-reperfusion injury(IRI) is an inherent feature of liver surgery and liver transplantation in which damage to a hypoxic organ(ischemia) is exacerbated following the return of oxygen delivery(reperfusion). IRI is a major cause of primary nonfunction after transplantation and may lead to graft rejection, regardless of immunological considerations. The immediate response involves the disruption of cellular mitochondrial oxidative phosphorylation and the accumulation of metabolic intermediates during the ischemic period, and oxidative stress during blood flow restoration. Moreover, a complex cascade of inflammatory mediators is generated during reperfusion, contributing to the extension of the damage and finally to organ failure. A variety of pharmacological interventions(antioxidants, anticytokines, etc.) have been proposed to alleviate graft injury but their usefulness is limited by the local and specific action of the drugs and by their potential undesirable toxic effects. Polyethylene glycols(PEGs), which are non-toxic water-soluble compounds approved by the FDA, have been widely used as a vehicle or a base in food, cosmetics and pharmaceuticals, and also as adjuvants for ameliorating drug pharmacokinetics. Some PEGs are also currently used as additives in organ preservation solutions prior to transplantation in order to limit the damage associated with cold ischemia reperfusion. More recently, the administration of PEGs of different molecular weights by intravenous injection has emerged as a new therapeutic tool to protect liver grafts from IRI. In this review, we summarize the current knowledge concerning the use of PEGs as a useful target for limiting liver IRI.

关键词： Ischemia reperfusion injury Polyethylene glycol Liver preconditioning Liver transplantation uW solution IGL-1 solution SCOT solution PEG rinse solution Machine perfusion

Effect of Mitochondrial Dysfunction on Carbon Metabolism and Gene Expression in Flower Tissues of Arabidopsis thaliana

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Molecular Plant 2011年第1期4卷 127-143页

作者： maria V. Busi maria E. Gomez-Lobato Sebastian P. Rius Valeria R. Turowski Paula Casati Eduardo J. Zabaleta Diego F. Gomez-Casati Alejandro Araya Instituto de Investigaciones Biotecnologicas-lnstituto Tecnologico de ChascomOs (IIB-INTECH) CONICET/uNSAM Chascomus Argentina Centro de Estudios Fotosinteticos y Bioquimicos (CEFOBI) Universidad Nacional de Rosario Argentina Instituto de Investigaciones Biologicas liB CONICET-Universidad Nacional de Mar del Plata Argentina Microbiologie Cellulaire et Moleculaire et Pathogenicite UMR 5234 Centre National de la Recherche Scientifique and Universite Victor Segalen-Bordeaux 2 Bordeaux France

We characterized the transcriptomic response of transgenic plants carrying a mitochondrial dysfunction induced by the expression of the unedited form of the ATP synthase subunit 9. The u-ATP9 transgene driven by A9 and APETALA3 promoters induce mitochondrial dysfunction revealed by a decrease in both oxygen uptake and adenine nucleo- tides （ATP, ADP） levels without changes in the ATIP/ADP ratio. Furthermore, we measured an increase in ROS accumulation and a decrease in glutathione and ascorbate levels with a concomitant oxidative stress response. The transcriptome analysis of young Arabidopsis flowers, validated by qRT-PCR and enzymatic or functional tests, showed dramatic changes in u-ATP9 plants. Both lines display a modification in the expression of various genes involved in carbon, lipid, and cell wall metabolism, suggesting that an important metabolic readjustment occurs in plants with a mitochondrial dysfunction. Interestingly, transcript levels involved in mitochondrial respiration, protein synthesis, and degradation are affected. More- over, the levels of several mRNAs encoding for transcription factors and DNA binding proteins were also changed. Some of them are involved in stress and hormone responses, suggesting that several signaling pathways overlap. Indeed, the tran- scriptome data revealed that the mitochondrial dysfunction dramatically alters the expression of genes involved in signaling pathways, including those related to ethylene, absicic acid, and auxin signal transduction. Our data suggest that the mitochondrial dysfunction model used in this report may be useful to uncover the retrograde signaling mechanism between the nucleus and mitochondria in plant cells.

关键词： Electron transport transcriptome analysis Arabidopsis.

Replication of interleukin 23 receptor and autophagy-related 16-like 1 association in adult-and pediatric-onset inflammatory bowel disease in Italy

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World Journal of Gastroenterology 2008年第29期14卷 4643-4651页

作者： Anna Latiano Orazio Palmieri maria Rosa Valvano Renata D'Incà Salvatore Cucchiara Gabriele Riegler Anna maria Staiano Sandro Ardizzone Salvatore Accomando Gian Luigi de Angelis Giuseppe Corritore Fabrizio Bossa Vito Annese u.u. O.O. di Gastroenterologia ed Endoscopia Ospedale IRCCS-CSSSan Giovanni Rotondo (Fg) 71013 Italy Cattedra di Gastroenterologia Università di PadovaPadova 35122 Italy Clinica Pediatrica università "La Sapienza" Roma 00185 Italy Cattedra di Gastroenterologia Università di NapoliNapoli 80131 Italy Clinica Pediatrica università di Napoli Napoli 80131 Italy unità di Gastroenterologia Ospedale "Sacco" Milano 20157 Italy Clinica Pediatrica università di Palermo Palermo 90128 Italy Clinica Pediatrica università di Parma Parma 43100 Italy

AIM: To investigate gene variants in a large Italian inflammatory bowel disease (IBD) cohort, and to analyze the correlation of sub-phenotypes (including age at diagnosis) and epistatic interaction with other IBD genes. METHODS: Total of 763 patients with Crohn's disease (CD, 189 diagnosed at age ulcerative colitis (uC, 179 diagnosed uded in the study. The rs2241880 [autophagy-related 16-like 1 (ATG16L1)], rs11209026 and rs7517847 [interleukin 23 receptor (IL23R)], rs2066844, rs2066845, rs2066847 (CARD15), rs1050152 (OCTN1), and rs2631367 (OCTN2) gene variants were genotyped. RESuLTS: The frequency of G allele of ATG16L1 SNP (Ala197Thr) was increased in patients with CD compared with controls (59% vs 54% respectively) (OR = 1.25, CI = 1.08-1.45, P = 0.003), but not in uC (55%). The frequency of A and G (minor) alleles of Arg381Gln, rs11209026 and rs7517847 variants of IL23R were reduced significantly in CD (4%, OR = 0.62, CI = 0.45-0.87, P = 0.005; 28%, OR = 0.64, CI = 0.55-0.75, P ut not G) was also reduced signifi cantly in uC (4%, OR = 0.69, CI = 0.5-0.94, P = 0.019). No association was demonstrated with sub-phenotypes and interaction with CARD15 , and OCTN1/2 genes, although both gene variants were associated with pediatric-onset disease. CONCLuSION: The present study confirms the association of IL23R polymorphisms with IBD, and ATG16L1 with CD, in both adult- and pediatric-onset subsets in our study population.

关键词： Inflammatory bowel disease Crohn'sdisease ulcerative colitis Genetic predisposition Autophagy-related 16-like 1 Interleukin 23 receptor Genome-wide association study Pediatric inflammatorybowel disease

Muscle fatigue in women with primary biliary cirrhosis:Spectral analysis of surface electromyography

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World Journal of Gastroenterology 2006年第32期12卷 5186-5190页

作者： maria Rosa Biagini Alessandro Tozzi Antonello Grippo Andrea Galli Stefano Milani Aldo Amantini Department of Clinical Pathophysiology Gastroenterology unit University of FlorenceAOU CareggiFirenzeItaly Department of Neurological Science Neurophysiological unit University of FlorenceAOU CareggiFirenzeItaly

AIM： To evaluate the myoelectric manifestations of peripheral fatigability in patients with primary biliary cirrhosis in comparison to healthy subjects. METHODS： Sixteen women with primary biliary cirrhosis without comorbidity and 13 healthy women matched for age and body mass index （BMI） completed the selfreported questionnaire fatigue impact scale. All subjects underwent surface electromyography assessment of peripheral fatigability. Anterior tibial muscle isometric voluntary contraction was executed for 20 s at 80% of maximal voluntary isometric contraction. During the exercise electromyographic signal series were recorded and root mean square （expression of central drive） as well as mean and median of electromyographic signal frequency spectrum （estimates of muscle fatigability） were com- puted. Each subject executed the trial two times. EMG parameters were normalized, then linear regression was applied and slopes were calculated. RESuLTS： Seven patients were fatigued （median fatigue impact scale score： 38, range： 26-66） and 9 were not fatigued （median fatigue impact scale score： 7, range： 0-17）. The maximal voluntary isometric contraction was similar in patients （82, 54-115 N） and controls （87, 74-101 N）, and in patients with high （81, 54-115 N） and low fatigue impact scale scores （86, 65-106 N）. Root mean square as well as mean and median of frequency spectrum slopes were compared with the Mann-Whitney u test, and no significant difference was found between fatigued and non-fatigued patients and controls. CONCLuSION： No instrumental evidence of peripheral fatigability can be found in women with primary biliary cirrhosis but no comorbidity, suggesting that fatigue in such patients may be of central origin.

关键词： Primary biliary cirrhosis Cholestasis Surfaceelectromyography Peripheral fatigue Muscle fatigue Fatigability Root mean square Mean frequency Medianfrequency Fatigue impact scale

Physiological and druggable skipping of immunoglobulin variable exons in plasma cells

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Cellular & Molecular Immunology 2019年第10期16卷 810-819页

作者： Mohamad Omar Ashi Nivine Srour Jean-Marie Lambert Anne Marchalot Ophelie Martin Sandrine Le Noir Eric Pinaud maria Victoria Ayala Christophe Sirac Jerome Sauliere Jerome Moreaux Michel Cogne Laurent Delpy unite Mixte de Recherche Centre National de la Recherche Scientifique 7276 INSERM U1262-Controle de la Reponse Immune B et LymphoproliferationsUniversitede LimogesLimogesFrance Institute of Human Genetics CNRS-UM UMR9002Department of Biological HaematologyCHU MontpellierUniversity of MontpellierUFR MedecineMontpellierFrance Institut universitaire de France Universitede LimogesLimogesFrance Present address:Lady Davis Institute for Medical Research McGill University3755 Cote Ste-Catherine RoadMontrealQC H3T 1E2Canada

The error-prone V(D)J recombination process generates considerable amounts of nonproductive immunoglobulin(Ig)*** recently demonstrated that aberrant Ig chains lacking variable(V)domains can be produced after nonsense-associated altered splicing(NAS)***,the expression of these truncated Ig polypeptides heightens endoplasmic reticulum stress and shortens plasma cell(PC)*** questions remain regarding the molecular mechanisms underlying this new truncated Ig exclusion(TIE-)checkpoint and its restriction to the ultimate stage of B-cell *** address these issues,we evaluated the extent of NAS of Ig pre-mRNAs using an Ig heavy chain(IgH)knock-in model that allows for uncoupling of V exon skipping from TIE-induced *** found high levels of V exon skipping in PCs compared with B cells,and this skipping was correlated with a biallelic boost in IgH transcription during PC *** analysis further revealed that the skipped V exon turned into a ***,we showed that hypertranscription of Ig genes facilitated V exon skipping upon passive administration of splice-switching antisense oligonucleotides(ASOs).Thus,V exon skipping is coupled to transcription and increases as PC differentiation proceeds,likely explaining the late occurrence of the TIE-checkpoint and opening new avenues for ASO-mediated strategies in PC disorders.

关键词： Immunoglobulin Exon skipping Plasma cells Antisense Oligonucleotides Nonsense-associated altered splicing

Antibacterial approaches in tissue engineering using metal ions and nanoparticles:From mechanisms to applications

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Bioactive Materials 2021年第12期6卷 4470-4490页

作者： maria Godoy-Gallardo ulrich Eckhard Luis M.Delgado Yolanda J.D.de Roo Puente Mireia Hoyos-Nogués F.Javier Gil Roman A.Perez Bioengineering Institute of Technology Universitat Internacional de CatalunyaCarrer de Josep Trueta08195del VallèsSant CugatBarcelonaSpain Proteolysis Lab Department of Structural BiologyMolecular Biology Institute of BarcelonaCSICBarcelona Science ParkBaldiri Reixac 15-2108028BarcelonaSpain

Bacterial infection of implanted scaffolds may have fatal consequences and,in combination with the emergence of multidrug bacterial resistance,the development of advanced antibacterial biomaterials and constructs is of great *** decades ago,metals and their ions had been used to minimize bacterial infection risk and,more recently,metal-based nanomaterials,with improved antimicrobial properties,have been advocated as a novel and tunable alternative.A comprehensive review is provided on how metal ions and ion nanoparticles have the potential to decrease or eliminate unwanted *** mechanisms such as oxidative stress induction,ion release and disruption of biomolecules are currently well ***,the exact antimicrobial mechanisms of the discussed metal compounds remain poorly *** combination of different metal ions and surface decorations of nanoparticles will lead to synergistic effects and improved microbial killing,and allow to mitigate potential side effects to the *** with a general overview of antibacterial mechanisms,we subsequently focus on specific metal ions such as silver,zinc,copper,iron and gold,and outline their distinct modes of ***,we discuss the use of these metal ions and nanoparticles in tissue engineering to prevent implant failure.

关键词： Metal ions Metal nanoparticles Mechanism of action Antibacterial activity Tissue engineering Biomaterials applications

Tubulointerstitial nephritis and uveitis syndrome post-COVID-19

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Pediatric Investigation 2023年第1期7卷 57-59页

作者： maria Cristina Maggio Filippo Collura maria Michela D’Alessandro Barbara Gramaglia Giovanni Corsello university Department PROMISE"G.D’Alessandro University of Palermo-Children Hospital"G.Di Cristina"A.R.N.A.S.PalermoItaly u.O.C.of Paediatric Nephrology Children Hospital"G.Di Cristina"A.R.N.A.S.PalermoItaly

To the editor:The angiotensin-converting-enzyme-2(ACE2)receptor is expressed in many extrapulmonary organs:eyes(conjunctival,corneal,and limbal epithelial cell,retina),nerves,vessels,small intestine enterocytes,kidney... 详细信息

关键词： ACE2 intestine organs

Study on Zymomonas Mobilis Growth and Its Relationship with Glutaminase Production by using Statistical Tools

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Journal of Life Sciences 2010年第4期4卷 45-51页

作者： Gilcelene Bruzon Joao Batista Buzato maria Antonia Pedrine Colabone Celligoi Department of Biochemistry and Biotechnology State University of Londrina Londrina Parana 86051-990 Brazil

Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has been studied for ethanol production, however, there is no study regarding glutaminase production. The aim of the present study was to establish the influencing factors for the growth of Z mobilis and its relationship with glutaminase production using statistical tools. Analysis of variance in blocks was carried out in a complete block design and the Tukey test demonstrated the importance of the components of the culture medium, absence of agitation and fermentation time. Minimum culture medium was used in the optimization varying the glucose concentrations （10, 30, and 50 g/L）, glutamine （0, 0.5 and 1g/L） and culture time （18, 24 and 30 hours）. Maximum production was obtained at 8.86 u/L glutaminase. Optimized conditions were used in the growth kinetics, where typical exponential growth was observed. Glutaminase production was shown to be related to biomass production.

关键词： Zymomonas mobilis glutaminase production Tukey test surface response design.