Search results for "Clos"

showing 10 items of 1439 documents

Clostridium perfringens (Holland) as an indicator of human effluent in the sediment of Lake Tuomiojärvi, central Finland

1983

The horizontal and vertical distribution of the gram-positive, non-motile, spore-forming and rod-shaped bacterium Clostridium perfringens Holland was studied. The aim of the study was to estimate the quantity of C. perfringens at different depths of the sediment and evaluate the effect of human effluent which the lake received between 1940 and 1956. C. perfringens lives in the colon of man. Because it is spore forming and cannot multiply under a temperature of 20 °C and, according to the studies of Seppanen et al. (1979) it can be at least 300 years old, it may be a suitable paleolimnological indicator of pollution by human effluent.

PollutionSpore forming bacteriaEcologymedia_common.quotation_subjectfungiSedimentClostridium perfringensmedicine.disease_causePaleolimnologyEnvironmental chemistrymedicineEnvironmental scienceEutrophicationEffluentmedia_common
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Ionic Hydrogel Based on Chitosan Cross-Linked with 6-Phosphogluconic Trisodium Salt as a Drug Delivery System.

2018

[EN] In this work, 6-phosphogluconic trisodium salt (6-PG(-)Na(+)) is introduced as a new aqueous and nontoxic cross-linking agent to obtain ionic hydrogels. Here, it is shown the formation of hydrogels based on chitosan cross-linked with 6-PG(-)Na(+). This formulation is obtained by ionic interaction of cationic groups of polymer with anionic groups of the cross linker. These hydrogels are nontoxic, do not cause dermal irritation, are easy to extend, and have an adequate adhesion force to be applied as polymeric film over the skin. This AWN formulation exhibits a first order release kinetic and can be applied as drug vehicle for topical administration or as wound dressing for wound healing…

Polymers and PlasticsPolymersAdministration TopicalIonic bondingSalt (chemistry)Bioengineering02 engineering and technology010402 general chemistry01 natural sciencesGluconatesHydrogel Polyethylene Glycol DimethacrylateBiomaterialsChitosanchemistry.chemical_compoundQUIMICA ORGANICADrug Delivery SystemsMaterials ChemistryHumanschemistry.chemical_classificationChitosanWound HealingAqueous solutionWound Closure TechniquesSodiumCationic polymerization021001 nanoscience & nanotechnology0104 chemical sciencesDrug vehicleKineticsCross-Linking ReagentsChemical engineeringchemistrySelf-healing hydrogelsDrug delivery0210 nano-technologyBiomacromolecules
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Blenders near polynomial product maps of $\mathbb C^2$

2021

In this paper we show that if $p$ is a polynomial which bifurcates then the product map $(z,w)\mapsto(p(z),q(w))$ can be approximated by polynomial skew products possessing special dynamical objets called blenders. Moreover, these objets can be chosen to be of two types : repelling or saddle. As a consequence, such product map belongs to the closure of the interior of two different sets : the bifurcation locus of $H_d(\mathbb P^2)$ and the set of endomorphisms having an attracting set of non-empty interior. In an independent part, we use perturbations of H\'enon maps to obtain examples of attracting sets with repelling points and also of quasi-attractors which are not attracting sets.

PolynomialEndomorphismMathematics::Dynamical SystemsMathematics - Complex VariablesApplied MathematicsGeneral Mathematics010102 general mathematicsClosure (topology)BlendersattractorsDynamical Systems (math.DS)01 natural sciencesSet (abstract data type)CombinatoricsBifurcation locusProduct (mathematics)AttractorFOS: MathematicsComplex Variables (math.CV)0101 mathematics[MATH]Mathematics [math]Mathematics - Dynamical SystemsbifurcationsSaddleMathematics
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Superinvolutions on upper-triangular matrix algebras

2018

Let UTn(F) be the algebra of n×n upper-triangular matrices over an algebraically closed field F of characteristic zero. In [18], the authors described all abelian G-gradings on UTn(F) by showing that any G-grading on this algebra is an elementary grading. In this paper, we shall consider the algebra UTn(F) endowed with an elementary Z2-grading. In this way, it has a structure of superalgebra and our goal is to completely describe the superinvolutions which can be defined on it. To this end, we shall prove that the superinvolutions and the graded involutions (i.e., involutions preserving the grading) on UTn(F) are strictly related through the so-called superautomorphisms of this algebra. We …

PolynomialPure mathematicsAlgebra and Number Theory010102 general mathematicsPolynomial identity superinvolution upper-triangular matrices.Zero (complex analysis)Triangular matrixStructure (category theory)010103 numerical & computational mathematicsSingle class01 natural sciencesSuperalgebraSettore MAT/02 - Algebrapolynomial identity superinvolutions upper triangular matrices cocharacter0101 mathematicsAbelian groupAlgebraically closed fieldMathematics
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Darboux Linearization and Isochronous Centers with a Rational First Integral

1997

Abstract In this paper we study isochronous centers of polynomial systems. It is known that a center is isochronous if and only if it is linearizable. We introduce the notion of Darboux linearizability of a center and give an effective criterion for verifying Darboux linearizability. If a center is Darboux linearizable, the method produces a linearizing change of coordinates. Most of the known polynomial isochronous centers are Darboux linearizable. Moreover, using this criterion we find a new two-parameter family of cubic isochronous centers and give the linearizing changes of coordinates for centers belonging to that family. We also determine all Hamiltonian cubic systems which are Darbou…

PolynomialPure mathematicsApplied Mathematics010102 general mathematicsMathematical analysisClosure (topology)Zero (complex analysis)Center (group theory)Function (mathematics)Darboux integral01 natural sciences010101 applied mathematicsNonlinear Sciences::Exactly Solvable and Integrable SystemsLinearization0101 mathematicsAnalysisHamiltonian (control theory)Astrophysics::Galaxy AstrophysicsMathematicsJournal of Differential Equations
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Non-Gaussian Approach for Stochastic Analysis of Offshore Structures

1995

An approach that is able to obtain the stochastic characteristics in terms of, stochastic momen.ts of a SDOF system excited by loads due to a fluid-structure mteraction is presented. In This approach the fluid horizontal velocity is considered as a filtered white noise, and the actual load expression is replaced by a Thirddegree polynomial of this velocity. The tools needed to p.romptly obtain the filters parameters and the equations governing the response moments are also presented; in particular, if the structure is sufficiently stiff, It is shown that these equations do not need any closure scheme III order to be solved. © ASCE.

PolynomialStochastic processMechanical EngineeringGaussianClosure (topology)White noiseStability (probability)Expression (mathematics)symbols.namesakeMechanics of MaterialsFluid–structure interactionsymbolsApplied mathematicsMechanics of MaterialAlgorithmMathematicsJournal of Engineering Mechanics
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A Case of Cardiomyopathy Due to Premature Ductus Arteriosus Closure: The Flip Side of Paracetamol.

2017

Paracetamol (acetaminophen or N-acetyl-p-aminophenol) is considered a safe analgesic and antipyretic nonsteroidal antiinflammatory drug commonly used during pediatric ages and during pregnancy. We report on a term neonate with closed ductus arteriosus, severe cardiomyopathy, right ventricular dysfunction, and functional stenosis of pulmonary arteries at birth after maternal self-medication with paracetamol and consumption of polyphenol-rich foods in late pregnancy. This drug, especially when associated with other vasoconstrictors (such as polyphenols), interferes with prostaglandin metabolism, which seriously accentuates the intrauterine ductus arteriosus constriction and leads to pharmacol…

Polyphenolmedicine.medical_specialtyDuctus ArteriosuVentricular Dysfunction RightCardiomyopathyHeart MurmurPulmonary Valve StenosiSelf MedicationDiet Mediterranean03 medical and health sciences0302 clinical medicinePregnancy030225 pediatricsInternal medicineDuctus arteriosusmedicineHumansVasoconstrictor AgentsAdverse effectCardiomyopathieAcetaminophenPregnancy030219 obstetrics & reproductive medicineHeart Murmursbusiness.industryDuctus arteriosus closureInfant NewbornPolyphenolsDuctus ArteriosusAnalgesics Non-Narcoticmedicine.diseaseAcetaminophenPulmonary Valve Stenosismedicine.anatomical_structurePrenatal Exposure Delayed EffectsPediatrics Perinatology and Child HealthPulmonary valve stenosiscardiovascular systemCardiologyHeart murmurFemalemedicine.symptomVasoconstrictor AgentbusinessCardiomyopathiesmedicine.drugHumanPediatrics
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The Impact of COVID-19 Pandemic and Lockdown Measures on Quality of Life among Italian General Population

2021

The COVID-19 pandemic that has hit the world in the year 2020 has put a strain on our ability to cope with events and revolutionized our daily habits. On 9 March, Italy was forced to lockdown to prevent the spread of the infection, with measures including the mandatory closure of schools and nonessential activities, travel restrictions, and the obligation to spend entire weeks in the same physical space. The aim of this study was to assess the impact of the COVID-19 pandemic and lockdown measures on quality of life (QoL) in a large Italian sample, in order to investigate possible differences in QoL levels related to both demographic and pandemic-specific variables. A total of 2251 Italian a…

PopulationPsychological interventionlcsh:Medicinegeneral populationArticleSocial grouplockdown03 medical and health sciences0302 clinical medicineQuality of lifehealth psychologyPandemicSettore M-PSI/07 - Psicologia DinamicaMedicine030212 general & internal medicineClosure (psychology)educationeducation.field_of_studybusiness.industrypandemiclcsh:RCOVID-19healthGeneral MedicinehumanitiesWHOQOL-BREFHealth psychologyCOVID-19; Quality of Life; pandemic; lockdown; gender differences; WHOQOL-BREF; health; health psychology; general population; ItalySnowball samplingItalygender differencesgender differenceQuality of Lifebusiness030217 neurology & neurosurgeryDemography
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Sports participation and cultural trends. Running as a reflection of individualisation and post-materialism processes in Spanish society

2014

AbstractThis article examines the relationship between cultural change processes and the practice of running. The empirical basis is the national survey on Spanish sport habits carried out in 2005. Specifically, the subsamples of runners (n = 343) and other sport modalities (n = 2,687) were used. The study reveals that runners are characterised by more post-materialist and individualist tendencies than the rest of the participants. The results suggest the existence of a close relationship between the predominant cultural orientations and certain types of sport activity.

Post-materialismModalitiesSociology and Political Science05 social sciencesPhysical Therapy Sports Therapy and RehabilitationGender studies030229 sport sciencesSociology of sport03 medical and health sciencesIndividualism0302 clinical medicineClose relationship0502 economics and businessOrthopedics and Sports MedicineSociologySocial sciencehuman activities050212 sport leisure & tourismEuropean Journal for Sport and Society
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Further evidence for an early Carboniferous (∼340 Ma) age of high-grade metamorphism in the Saxonian granulite complex

1998

U–Pb and Pb–Pb zircon ages for metamorphic zircons from granulites in the Saxonian granulite complex are reported, using the SHRIMP ion microprobe, conventional multigrain and single-gain techniques and the evaporation method. This is complemented by a Pb–Pb evaporation age for a post-granulite granite emplaced into the schist mantle around the granulites during uplift of the complex. We also demonstrate that zircon ages are not reset during high-grade metamorphism, as commonly argued, but have a very high closure temperature and usually preserve the isotopic composition reflecting the time of their formation. Multifaceted zircons from four granulite samples that probably grew close to the …

PrecambrianCarboniferousMetamorphic rockGeochemistrySchistGeneral Earth and Planetary SciencesMetamorphismPetrologyGranuliteClosure temperatureGeologyZirconGeologische Rundschau
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