Search results for "Chains"

showing 10 items of 257 documents

Central limit theorem for bifurcating Markov chains under L 2 -ergodic conditions

2021

Bifurcating Markov chains (BMC) are Markov chains indexed by a full binary tree representing the evolution of a trait along a population where each individual has two children. We provide a central limit theorem for additive functionals of BMC under L 2-ergodic conditions with three different regimes. This completes the pointwise approach developed in a previous work. As application, we study the elementary case of symmetric bifurcating autoregressive process, which justify the non-trivial hypothesis considered on the kernel transition of the BMC. We illustrate in this example the phase transition observed in the fluctuations.

fluctuations for tree indexed Markov chain60J80[MATH.MATH-PR] Mathematics [math]/Probability [math.PR]Bifurcating Markov chains60F05binary treesbifurcating auto-regressive processdensity estimation Mathematics Subject Classification (2020): 60J05
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Agri-Food Markets towards Sustainable Patterns

2020

In recent decades, the confluence of different global and domestic drivers has led to progressive and unpredictable changes in the functioning and structure of agri-food markets worldwide. Given the unsustainability of the current agri-food production, processing, distribution and consumption patterns, and the inadequate governance of the whole food system, the transition to sustainable agriculture and food systems has become crucial to effectively manage a global agri-food market able in supporting expected population growth and ensuring universal access to sufficient, safe, and nutritious food for all. Based on a critical review of the existing international literature, the paper seeks to…

food systemsGeography Planning and Developmentlcsh:TJ807-830lcsh:Renewable energy sourcesalternative food networks010501 environmental sciencesManagement Monitoring Policy and Lawsustainability transitions01 natural sciencesShort food supply chainfood policyBody of knowledge0502 economics and businessSustainable agricultureliberalizationAlternative food networkIndustrial organizationlcsh:Environmental sciences0105 earth and related environmental scienceslcsh:GE1-350Food securityRenewable Energy Sustainability and the Environmentlcsh:Environmental effects of industries and plants05 social sciencesfood securityShort food supply chainslanguage.human_languagenutritionlcsh:TD194-195Food systemSustainabilityFood policylanguageFood systemsWhole food050202 agricultural economics & policyBusinessshort food supply chainsglobalizationSustainability
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Angiopoietin-2 plasma dosage predicts time to first treatment and overall survival in chronic lymphocytic leukemia.

2010

Abstract The clinical relevance of angiopoietin-2 (Ang2) in chronic lymphocytic leukemia (CLL) was previously suggested by the association between high Ang2, and shorter progression-free survival reported in small series of patients. Here, we evaluated Ang2 glycoprotein levels in plasma samples collected from a multicentric cohort of CLL patients (n = 316) using an enzyme-linked immunosorbent assay method, and we investigated its prognostic role in relation to time to first treatment (TTFT) and overall survival. Based on a cutoff equal to 2459 pg/mL, we divided our cohort in 2 subsets (high and low Ang2) composing 100 (31.6%) and 216 (68.4%) patients, respectively. High Ang2 was predictive …

glycoproteinMaleTime FactorsZAP-70Chronic lymphocytic leukemiavascular endothelial growth factor aBiochemistryGastroenterologyimmunoglobulin heavy chainsAdult Aged Aged; 80 and over Angiopoietin-2; analysis/blood Blood Chemical Analysis Female Humans Leukemia; Lymphocytic; Chronic; B-Cell; blood/diagnosis/mortality/therapy Male Middle Aged Neoadjuvant Therapy Prognosis Survival Analysis Time Factors Tumor Markers; Biological; bloodBlood plasma80 and overChronicTumor MarkersAged 80 and overLeukemiaHematologyHazard ratioprotein kinaseHematologyanalysis/bloodMiddle Agedchronic b-cell leukemiasPrognosisLymphocyticNeoadjuvant TherapyLeukemiaCohortFemaleAdultmedicine.medical_specialtyImmunologyangiopoietins chronic b-cell leukemias chronic lymphocytic leukemia plasma vascular endothelial growth factor a cd38 enzyme-linked immunosorbent assay glycoprotein immunoglobulin heavy chains protein kinaseNOcd38Angiopoietin-2bloodInternal medicinemedicineBiomarkers Tumorchronic lymphocytic leukemia angiopoietin-2.Humansbeta(2)-microglobulinplasmaSurvival analysisblood/diagnosis/mortality/therapyAgedbusiness.industryB-CellCell BiologyBiologicalmedicine.diseaseLeukemia Lymphocytic Chronic B-CellSurvival AnalysisConfidence intervalImmunologychronic lymphocytic leukemiaangiopoietin-2enzyme-linked immunosorbent assaybusinessCLL; angiopoietin-2; beta(2)-microglobulin; ZAP-70; CD38Settore MED/15 - Malattie del SangueangiopoietinsBlood Chemical AnalysisCLLCD38Blood Chemical Analysis; Angiopoietin-2; Humans; Neoadjuvant Therapy; Prognosis; Aged; Aged 80 and over; Leukemia Lymphocytic Chronic B-Cell; Adult; Middle Aged; Tumor Markers Biological; Time Factors; Female; Male; Survival Analysis
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A Comparison between the Latest Models of Li-Ion Batteries and Petrol Chainsaws Assessing Noise and Vibration Exposure in Cross-Cutting

2023

Chainsaw operators are exposed to many hazards that can lead to health problems. The two most frequently documented ergonomics threats in the use of chainsaws are noise and vibration exposure. Since the use of battery chainsaws is increasing due to the growing improvements in battery life and power, the study aims to compare the difference in terms of noise emission and vibration levels of the following two new models of chainsaws: the battery-powered Stihl MSA 300 and the petrol-powered Stihl MS 261 C-M. Black pine and European beech logs were cross-cut in order to evaluate both noise and vibration exposure. The results show that the use of battery-powered chainsaws, in comparison to the p…

hand-arm vibrationchainsaw; battery; wood density; wood defects; hand-arm vibration; noise; ergonomicswood defectnoiseergonomicsbatteryForestrywood densitychainsawSettore AGR/06 - Tecnologia Del Legno E Utilizzazioni ForestaliForests
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Su certe classi di gruppi unipotenti

2005

We introduce some results characterizing unipotent algebraic groups having a chain as the lattice of connected subgroups and we discuss some consequent results.

lattices of connected subgroupsalgebraic groupsunipotent groupschains of subgroups
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Flow Behavior of Chain and Star Polymers and Their Mixtures

2018

Star-shaped polymers show a continuous change of properties from flexible linear chains to soft colloids, as the number of arms is increased. To investigate the effect of macromolecular architecture on the flow properties, we employ computer simulations of single chain and star polymers as well as of their mixtures under Poiseuille flow. Hydrodynamic interactions are incorporated through the multi-particle collision dynamics (MPCD) technique, while a bead-spring model is used to describe the polymers. For the ultradilute systems at rest, the polymers are distributed uniformly in the slit channel, with a weak dependence on their number of arms. Once flow is applied, however, we find that the…

lcsh:QD241-441starsseparationlcsh:Organic chemistry530 Physicschainsmicrofluidicssimulations530 PhysikArticlepolymersPoiseuille flowPolymers
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The difference of free light chains as a predictor of kidney damage in patients with Multiple Myeloma

2022


 Background: Multiple myeloma (MM) is a malignant neoplasm characterized by the clonal expansion of plasma cells that can release monoclonal immunoglobulins (monoclonal component) or part of theme. Since 2001, the k and λ serum free light chains (sFLC) evaluation and their ratio (rFLC) have made up the laboratory analysis more sensitive and precise in MM patients. The role of rFLC has been widely studied and discussed and now it is validated in the literature. Instead, the value of free light chains difference (dFLC), especially in MM is less known yet. The aim of this study is to evaluate the relationship between the dFLC and the kidney damage parameters in patients with MM, in compa…

lcsh:R5-920medicine.medical_specialtyKidneyCreatinineeducation.field_of_studyProteinuriabusiness.industrylcsh:Public aspects of medicinePopulationUrologyRenal functionlcsh:RA1-1270medicine.diseaseImmunoglobulin light chainMultiple Myeloma free light chains difference free light chains ratio renal damagechemistry.chemical_compoundmedicine.anatomical_structurechemistrymedicineAlbuminuriamedicine.symptomlcsh:Medicine (General)businesseducationMultiple myelomaEpidemiology, Biostatistics, and Public Health
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Dynamics in stochastic evolutionary models

2014

First published: 01 February 2016 We characterize transitions between stochastically stable states and relative ergodic probabilities in the theory of the evolution of conventions. We give an application to the fall of hegemonies in the evolutionary theory of institutions and conflict, and illustrate the theory with the fall of the Qing dynasty and the rise of communism in China. We are especially indebted to Juan Block for his many comments and suggestions. We would also like to thank Drew Fudenberg, Kevin Hasker, Matt Jackson, Peyton Young, and five anonymous referees. We are grateful to NSF Grant SES-08-51315 and to the MIUR PRIN 20103S5RN3 for financial support.

markov chainsEvolutionMarkov chainjel:C73conventionsEvolution conventionsmarkov chainsstate powerEconomics Econometrics and Finance (all)2001 Economics Econometrics and Finance (miscellaneous)C73state powerPracticesconventionddc:330Equilibrium SelectionLawPragmatismconventions; Evolution; Markov chains; state power; Economics Econometrics and Finance (all)2001 Economics Econometrics and Finance (miscellaneous)Theoretical Economics
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Cost Effectiveness of Peginterferon ??-2a Plus Ribavirin versus Interferon ??-2b Plus Ribavirin as Initial Therapy for Treatment-Naive Chronic Hepati…

2004

Introduction: In adults with previously untreated chronic hepatitis C (CHC), the combination of peginterferon α-2a plus ribavirin produces a higher rate of sustained virological response (SVR) than interferon α-2b plus ribavirin, but it is still unproven whether this increase is cost effective. The objective of this study was to determine if the gain in SVR with peginterferon α-2a plus ribavirin is worth the incremental cost. Methods: We constructed a Markov model of disease progression in which cohorts of patients received peginterferon α-2a plus ribavirin or interferon α-2b plus ribavirin for 48 weeks (hepatitis C virus [HCV] genotype 1 and non-1 patients with fibrosis) or 24 weeks (genot…

medicine.medical_specialtyCirrhosisGenotypeCost effectivenessCost-Benefit AnalysisHepatitis C virusInterferon alpha-2medicine.disease_causeAntiviral AgentsSensitivity and SpecificityGastroenterologypeginterferon alpha2aPolyethylene Glycolschemistry.chemical_compoundchronic hepatitiInterferonInternal medicineRibavirinmedicineHumansRandomized Controlled Trials as Topicalpha2b interferonAntiviral AgentPharmacologybusiness.industryHealth PolicyRibavirinPublic Health Environmental and Occupational HealthInterferon-alphavirus diseasesHealth Care CostsHepatitis CHepatitis C Chronicmedicine.diseaseMarkov ChainsRecombinant Proteinsdigestive system diseasesModels EconomicTreatment OutcomechemistryImmunologyQuality of LifePeginterferon alfa-2bDrug Therapy CombinationbusinessPeginterferon alfa-2amedicine.drugPharmacoEconomics
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Cost-effectiveness of screening for colorectal cancer in France using a guaiac test versus an immunochemical test

2010

Objectives: The aim of this study was to compare the cost and the effectiveness of two biennial fecal occult blood screening tests for colorectal cancer: a guaiac nonrehydrated test (G-FOBT) and an immunochemical test (I-FOBT) with the absence of screening.Methods: A Markov model was developed to compare these strategies in a general population of subjects aged 50 to 74 over a 20-year period.Results: Compared with the absence of screening, G-FOBT and I-FOBT were associated with a decrease in colorectal cancer mortality of 17.4 percent and 25.2 percent, respectively. With regard to cost-effectiveness, expressed as cost per life-year gained, I-FOBT was the most effective and most costly alter…

medicine.medical_specialtyColorectal cancerCost effectivenessCost-Benefit Analysishealth care facilities manpower and serviceseducationPopulationImmunologic TestsSensitivity and SpecificityInternal medicinemedicineHumansMass ScreeningeducationSensitivity analyseshealth care economics and organizationsMass screeningAgedGynecologyeducation.field_of_studybiologybusiness.industryHealth PolicyEurosMiddle Agedmedicine.diseasebiology.organism_classificationMarkov Chainsdigestive system diseasesTest (assessment)surgical procedures operativeFecal occult blood screeningOccult BloodIndicators and ReagentsFranceColorectal NeoplasmsGuaiacbusinessInternational Journal of Technology Assessment in Health Care
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