Search results for "Root"

showing 10 items of 1237 documents

Impact de l'intervalle d'échantillonnage sur les tests d'efficience : application au marché français des actions

1994

Efficiency of financial markets is one of the most studied subject in theoretical finance. Formalization of this idea is realised by the random walk model. Numerous tests have been developped to validate the hypothesis of identically and independantly distributed innovations. But the results of empirical works are not unanimous ; the acceptation of the random walk is not systematic and depend too much on sample features. This constatation leads us to study the impact of the sample frequency on empirical results by distinguishing two different methodologies of tests : the first one is based on unit root (DICKEY et FULLER 1979, 1981) and the other one on variance ratio (LO et MACKINLAY 1988).…

Tests de racine unitaireTests de ratio de varianceVariance ration testsEfficience[ SHS.ECO ] Humanities and Social Sciences/Economies and financesEfficiencyUnit root tests[SHS.ECO] Humanities and Social Sciences/Economics and Finance[SHS.ECO]Humanities and Social Sciences/Economics and Finance
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Narrativa dei Caraibi nel nuovo millennio

2020

L’etichetta “Letterature franco-caraibica” utilizzata, per convenzione, dalla critica per indicare unitariamente la produzione letteraria in lingua francese della regione centrale del Continente americano è assai impropria. La regione dei Caraibi abbraccia, infatti, sia alcune delle isole dell’arcipelago delle Piccole Antille (Martinica, Guadalupa), sia l’isola di Haïti, che fa parte delle Grandi Antille, che la Guiana incastonata sulla costa orientale dell’America meridionale. Pur nella diversità dei movimenti ideologici e degli avvenimenti storici che si sono succeduti nella regione, le opere letterarie degli scrittori caraibici francofoni, nel loro insieme, hanno oscillato, e continuano …

The definition "Franco-Caribbean Literature" used by convention from the critique to indicate all the literary production in French of the central region of the American continent is very improper. The Caribbean region includes in fact the islands of Martinique Guadeloupe Haïti and the Guiana. Despite the diversity of ideological movements and historical events that took place in these countries the literary works of the Caribbean writers have fluctuated and continue to oscillate between two tendencies: that of rooting in tradition and that of escape from it. The writers show themselves open to comparison and dialogue with other literary and cultural traditions in order to create a narrative form that corresponds to the many inheritances of those composite populations. Here the cultural syncretism that has been created allows to recognize a common identity in the name of all that the West wanted to extinguish. The common denominator seems to be inverted in the contradictory result of courageous but dangerous encounters of curiosities that can lead to conflicts to exclusions.
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Caraibi: un "archipel inachevé"

2018

L’etichetta “Letterature franco-caraibica” utilizzata, per convenzione, dalla critica per indicare unitariamente la produzione letteraria in lingua francese della regione centrale del Continente americano è assai impropria. La regione dei Caraibi abbraccia, infatti, sia alcune delle isole dell’arcipelago delle Piccole Antille (Martinica, Guadalupa), sia l’isola di Haïti, che fa parte delle Grandi Antille, che la Guiana incastonata sulla costa orientale dell’America meridionale. Pur nella diversità dei movimenti ideologici e degli avvenimenti storici che si sono succeduti nella regione, le opere letterarie degli scrittori caraibici francofoni, nel loro insieme, hanno oscillato, e continuano …

The definition "Franco-Caribbean Literature" used by convention from the critique to indicate all the literary production in French of the central region of the American continent is very improper. The Caribbean region includes in fact the islands of Martinique Guadeloupe Haïti and the Guiana. Despite the diversity of ideological movements and historical events that took place in these countries the literary works of the Caribbean writers have fluctuated and continue to oscillate between two tendencies: that of rooting in tradition and that of escape from it. The writers show themselves open to comparison and dialogue with other literary and cultural traditions in order to create a narrative form that corresponds to the many inheritances of those composite populations. Here the cultural syncretism that has been created allows to recognize a common identity in the name of all that the West wanted to extinguish. The common denominator seems to be inverted in the contradictory result of courageous but dangerous encounters of curiosities that can lead to conflicts to exclusions.Settore L-FIL-LET/14 - Critica Letteraria E Letterature Comparate
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Canopy Architecture Appraisal by Fractal Dimension of 'Flordastar' Peach Trees Grafted onto Different Rootstocks

2007

The objective of this research was to evaluate the modification of canopy architecture of ''Flordastar'' peach (Prunus persica L. Batsch) grafted onto rootstocks with different vigour, by the use of fractal dimension (D). The hypothesis was that different vigour rootstocks are able to modify the complexity of the branching pattern and that this effect can be assessed by a geometric parameter such as the fractal dimension (D) of the 2D projection of tree branching structure. The observations were carried out in a four-year-old experimental orchard of cv. ''Flordastar'' peach trees grafted onto Ishtara, Barrier, GF677 and MrS 2/5 rootstocks. On digital pictures of leafless, dormant peach tree…

The objective of this research was to evaluate the modification of canopy architecture of ''Flordastar'' peach (Prunus persica L. Batsch) grafted onto rootstocks with different vigour by the use of fractal dimension (D). The hypothesis was that different vigour rootstocks are able to modify the complexity of the branching pattern and that this effect can be assessed by a geometric parameter such as the fractal dimension (D) of the 2D projection of tree branching structure. The observations were carried out in a four-year-old experimental orchard of cv. ''Flordastar'' peach trees grafted onto Ishtara Barrier GF677 and MrS 2/5 rootstocks. On digital pictures of leafless dormant peach trees the tree skeleton was manually depicted by an image analysis software to measure total length and angles of insertion of branches. Bitmaps of the skeleton were then subjected to a specific software (FDCALC) able to calculate D by the "box counting" method. To account for the error introduced by analyzing a three dimensional structure with its 2D projection measurements were done on two images per tree taken from two different viewing angles. Results are shown in relation to tree vigour of the scion/stock combination. Fractal dimension was related to the vigour ranking of the graft combinations tested. In particular vigorous scion/stock combinations showed the highest D.HorticultureCanopy architectureHorticultureRootstockFractal dimensionMathematics
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Land surface temperature retrieval from LANDSAT TM 5

2004

In this paper, three methods to retrieve the land surface temperature (LST) from thermal infrared data supplied by band 6 of the Thematic Mapper (TM) sensor onboard the Landsat 5 satellite are compared. The first of them lies on the estimation of the land surface temperature from the radiative transfer equation using in situ radiosounding data. The others two are the mono-window algorithm developed by Qin et al. [International Journal of Remote Sensing 22 (2001) 3719] and the single-channel algorithm developed by Jime´nez-Mun˜oz and Sobrino [Journal of Geophysical Research 108 (2003)]. The land surface emissivity (LSE) values needed in order to apply these methods have been estimated from a…

Thermal infraredLans surface emissivityLand surface temperatureNear-infrared spectroscopyOtras Ciencias de la Tierra y relacionadas con el Medio AmbienteSoil ScienceGeologyLandsat 5Ciencias de la Tierra y relacionadas con el Medio AmbienteThematic MapperRadiative transferEmissivityEnvironmental scienceSatelliteComputers in Earth SciencesRoot-mean-square deviationLand Surface TemperatureCIENCIAS NATURALES Y EXACTASRemote sensing
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Effect of fatigue on the intra-cycle acceleration in front crawl swimming: a time-frequency analysis.

2007

The present study analyzes the changes in acceleration produced by swimmers before and after fatiguing effort. The subjects (n=15) performed a 25-m crawl series at maximum speed without fatigue, and a second series with fatigue. The data were registered with a synchronized system that consisted of a position transducer (1 kHz) and a video photogrametry (50 Hz). The acceleration (m s−2) was obtained by the derivative analysis of the variation of the position with time. The amplitude in the time domain was calculated with the root mean square (RMS); while the peak power (PP), the peak power frequency (PPF) and the spectrum area (SA) were calculated in the frequency domain with Fourier analysi…

Time FactorsAdolescentAcousticsBiomedical EngineeringBiophysicsPoison controllaw.inventionRoot mean squareAccelerationsymbols.namesakelawHumansOrthopedics and Sports MedicineTime domainSwimmingPhysicsFrequency analysisbusiness.industryRehabilitationReproducibility of ResultsStructural engineeringBiomechanical PhenomenaFourier analysisFrequency domainMuscle FatiguesymbolsbusinessFront crawlJournal of biomechanics
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Cytokine- and Interferon-Modulating Properties of Echinacea spp. Root Tinctures Stored at −20°C for 2 Years

2007

Echinacea spp. phytomedicines are popular for treating upper respiratory infections. The purpose of this investigation was to examine the immunomodulatory properties of Echinacea tinctures from seven species after being stored at -20 degrees C for 2 years. Two experimental techniques were employed using human peripheral blood mononuclear cells (PBMC). In the first set of experiments, PBMCs were stimulated in vitro with tinctures alone and assayed for proliferation and production of interleukin-10 (IL-10), IL-12, and tumor necrosis factor-alpha (TNF-alpha). In the second set of experiments, subjects were immunized with influenza vaccine. PBMCs from vaccinated individuals were stimulated in v…

Time FactorsDrug StorageImmunologyPeripheral blood mononuclear cellPlant RootsVirusArticleEchinaceaCytokine interferon Echinacea immunologyEchinacea (animal)Interferon-gammaImmune systemSpecies SpecificitySettore BIO/13 - Biologia ApplicataInterferonVirologymedicineHumansInterferon gammaCells CulturedCell ProliferationCryopreservationTraditional medicinebiologyPlant ExtractsTumor Necrosis Factor-alphaCell Biologybiology.organism_classificationInterleukin-12Interleukin-10Interleukin 10AlcoholsImmunologyInterleukin 12Leukocytes MononuclearCytokinesmedicine.drug
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Is rootstock-induced dwarfing in olive an effect of reduced plant hydraulic efficiency?

2006

We investigated the hydraulic architecture of young olive trees either self-rooted or grafted on rootstocks with contrasting size-controlling potential. Clones of Olea europea L. (Olive) cv ''Leccino'' inducing vigorous scion growth (Leccino ''Minerva'', LM) or scion dwarfing (Leccino ''Dwarf'', LD) were studied in different scion/rootstock combinations (LD, LM, LD/LD, LM/LM, LD/LM and LM/LD). Shoots growing on LD root systems developed about 50% less leaf surface area than shoots growing on LM root systems. Root systems accounted for 60-70% of plant hydraulic resistance (R), whereas hydraulic resistance of the graft union was negligible. Hydraulic conductance (K = 1/R) of LD root systems w…

Time FactorsPhysiologyWater potentialPlant ScienceRoot systemBiologyPlant RootsLeccinoOleaTranspirationGraftingTranspiration rateOlea europeaWaterBiological TransportHPFMGraftingbiology.organism_classificationOlive treesDwarfingPlant LeavesSettore AGR/03 - Arboricoltura Generale E Coltivazioni ArboreeHorticultureAgronomyOleaShootRootstockRoot hydraulic
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Changes in the Phytoalexin Content of Various Vitis Spp. in Response to Ultraviolet C Elicitation

1999

The phytoalexin production potential of three American Vitis species and that of three cultivars of Vitis vinifera were evaluated in response to UV-C irradiation. Time course changes in resveratrol, piceid, epsilon-viniferin, and pterostilbene contents were studied within 3 days after a short UV-C irradiation. Results show that the two major stilbenes accumulated as a response to UV-C elicitation are resveratrol and epsilon-viniferin, a resveratrol dehydrodimer, the concentration of both compounds usually reaching quantities >100 microgram/g of fresh weight. In contrast, piceid and pterostilbene were constantly produced in low quantities. Owing to the results obtained, the role of stilbene …

Time FactorsPterostilbeneUltraviolet RaysResveratrolTerpenechemistry.chemical_compoundPhytoalexinsBotanyVitis cinereaFood sciencewine.grape_varietyRosalesPiceidchemistry.chemical_classificationbiologyPlant ExtractsTerpenesPhytoalexinfood and beveragesRosalesGeneral Chemistrybiology.organism_classificationchemistrywineGeneral Agricultural and Biological SciencesRootstockSesquiterpenesJournal of Agricultural and Food Chemistry
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Er:YAG laser in defocused mode for scaling of periodontally involved root surfaces: An in vitro pilot study

2005

Item does not contain fulltext BACKGROUND: The Er:YAG laser may be used on periodontally involved teeth in combination with conventional periodontal therapy in order to improve the efficacy of root instrumentation. The aim of this study was to compare the effect of hand instrumentation on root surfaces of periodontally involved teeth with Er:YAG laser application. METHODS: Thirty freshly extracted, non-carious, single-rooted, periodontally diseased human teeth from adult humans with advanced periodontal disease were used in this study. The teeth were divided into three groups of 10 specimens each. Group A was treated with scaling and root planing (SRP) with curets only (control). In group B…

Tissue engineering and reconstructive surgery [UMCN 4.3]Adultlasers/therapeutic useRoot surfaceMaterials scienceperiodontal diseases/therapycomparison studies; lasers/therapeutic use; periodontal diseases/therapy; planing; scaling; tooth rootDentistryPilot Projectslaw.inventionRoot PlaningplaningScaling and root planingLaser applicationPeriodontal diseaselawtooth rootHumansDental CalculusLow-Level Light Therapycomparison studiesPeriodontal Diseasesbusiness.industryscalingDental scalingLaserPeriodonticsDental ScalingbusinessEr:YAG laserWater spray
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