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Estudo e caracterização de marcadores ópticos para a aterosclerose / Study and characterization of optical markers for atherosclerosisSICCHIERI, LETICIA B. 22 December 2016 (has links)
Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2016-12-22T16:50:04Z
No. of bitstreams: 0 / Made available in DSpace on 2016-12-22T16:50:04Z (GMT). No. of bitstreams: 0 / O presente trabalho buscou investigar a formação da placa de aterosclerose através de caracterização da autofluorescência do tecido e do plasma na presença de marcadores fluorescentes. Para realizar o estudo, coelhos foram divididos em dois grupos: um grupo controle onde os animais foram submetidos a uma dieta normal e um grupo experimental onde os animais foram submetidos a uma dieta hipercolesterolêmica. Foram realizadas duas experimentações animais: na primeira os animais foram sendo eutanasiados ao longo do experimento e suas artérias foram coletadas. Na segunda os animais foram acompanhados por no máximo 80 dias. Durante o experimento apenas o sangue foi coletado e os animais foram eutanasiados no final do experimento. Dois marcadores fluorescentes foram utilizados no trabalho: o complexo európio-clorotetraciclina (EuCTc) e o corante tioflavina T (ThT). Analisouse inicialmente a fluorescência dos marcadores na presença do plasma dos coelhos tanto para o grupo controle, quanto para o grupo experimental em função dos tempos de dieta. Para o complexo EuCTc observou-se duas bandas de emissão, com excitação em 400 nm, uma característica da clorotetraciclina, em 515 nm e uma em 617 nm característica do íon európio. A análise da banda do íon európio indicou um incremento da banda de emissão do complexo na presença do plasma do grupo experimental em relação ao grupo controle. Para o corante ThT também foi observado um aumento na banda de emissão em 480 nm, com excitação em 413 nm, para o grupo experimental em comparação com o grupo controle. A potencialidade de utilização do complexo EuCTc e EuCTcMg (EuCTc na presença do íon magnésio) para marcação da placa de aterosclerose nas artérias, foi estudada através da análise de microscopia de fluorescência. Observou-se que a emissão do complexo melhora muito a visualização da placa quando comparada com a autofluorescência. Observou-se, através de microscopia de tempo de vida de fluorescência, que há uma transferência de energia entre os fluoróforos presentes na placa e os complexos EuCTc e EuCTcMg. Essa transferência de energia ocasionou em uma diminuição drástica no tempo de vida de fluorescência dos fluoróforos nessa região. Por fim, estudou-se a geração de segundo harmônico do colágeno na placa de aterosclerose, sendo obtidas diferenças na quantidade e organização do colágeno para os diferentes grupos experimentais. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Desenvolvimento de biomarcador específico de células beta pancreáticas (incretina radiomarcada) para imagem da massa beta funcional em diabéticos e obesos: estudo em modelo animal / Development of biomarker specific of pancreatic beta cells (incretin radiolabelled) for image of beta functional mass in diabetic and obese: study in animal modelSEO, DANIELE 09 October 2017 (has links)
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-10-09T13:37:26Z
No. of bitstreams: 0 / Made available in DSpace on 2017-10-09T13:37:26Z (GMT). No. of bitstreams: 0 / O aumento nos casos de obesidade em todo o mundo tem gerado grande preocupação e estimulado pesquisas na prevenção e tratamento dessa condição patológica. A combinação de diabetes tipo 2 ou resistência insulínica com obesidade agrava o potencial evolutivo da enfermidade. Mesmo pacientes submetidos com sucesso à cirurgia bariátrica ou metabólica, podem não se curar do diabetes, pois a melhora das taxas circulantes de glicose e insulina nem sempre corresponde à recuperação da massa beta pancreática. Até o momento, não há consenso sobre como medir a massa de células beta in vivo. As ferramentas disponíveis padecem de baixa sensibilidade e especificidade, muitas vezes revelando-se também complexas e dispendiosas. Incretinas radiomarcadas ,como os análogos do peptídeo glucagon-like-peptide-1 / GLP-1, têm-se revelado promissoras para avaliação de células beta pancreáticas, em diabetes e insulinoma. O objetivo do presente trabalho foi o desenvolvimento de dois conjugados de análogo de incretina GLP-1, marcados com tecnécio-99m, a fim de propor um método não invasivo de imagem, para monitoração da massa de células beta pancreáticas, em organismos afetados por obesidade. O estudo foi conduzido em diferentes modelos animais, incluindo obesidade induzida por dieta hiperlipídica, estado pós-obesidade em que o distúrbio inicialmente gerado foi parcialmente corrigido, e como controle, diabetes induzido com aloxana. Nos resultados, os radiotraçadores alcançaram um rendimento radioquímico superior a 97%. O melhor radiomarcador, dentre os dois análogos ensaiados, foi o 99mTc-HYNIC-βAla-Exendin-4. Animais com obesidade induzida por dieta revelaram captação reduzida nas células beta pancreáticas. A restrição dietética (estado pós-obesidade) não se seguiu de recuperação completa, embora notável melhora de glicemia haja sido observada. Estudos futuros são indicados em modelos de obesidade, diabetes tipo 2 e tratamento dietético, incluindo cirurgia bariátrica e metabólica. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Diagnosis of orthopaedic prosthesis infections with radionuclide techniques; clinical application of various imaging methodsLarikka, M. (Martti) 23 January 2004 (has links)
Abstract
A variety of radiopharmaceuticals and imaging techniques are currently available for scintigraphic imaging of infections. However, comparisons on the clinical value of such techniques have been limited, especially in prosthesis infections.
This series included 138 cases with suspected prosthesis infections – 94 in hip and 44 in knee prostheses of patients whose final diagnoses were based on clinical, operative and microbiological findings, and who underwent three-phase bone, 99mTc -leukocyte and 99mTc-ciprofloxacin imaging in the Department of Clinical Chemistry, Oulu University Hospital and in the Laboratory, L?nsi-Pohja Central Hospital, during the years from 1993 to 2001.
The normal arterial and soft-tissue phase images of three-phase bone imaging practically excluded infection in hip prostheses, whereas these techniques frequently yielded false positive findings in patients with knee prostheses, resulting in specificity of 23% or less. In combined 99mTc-leukocyte/bone imaging, diagnostic accuracy was 80–86% at two- to four-hour images and 87–98% at 24-hour images. The 99mTc-ciprofloxacin images showed unspecific accumulation of tracer in the one-hour and four-hour images, which disappeared in the 24-hour images in most hip and knee prostheses. 99mTc-ciprofloxacin imaging yielded almost as good diagnostic accuracy as combined 99mTc-leukocyte/bone imaging.
In conclusion, in suspected hip prosthesis infections, normal findings in three-phase bone imaging exclude infection, whereas abnormal results in the arterial and soft-tissue phases should be confirmed with 99mTc-leukocyte imaging using 24-hour images. Contrary-wise, in suspected knee prosthesis infections, 99mTc-leukocyte imaging with 24-hour images is the first-line examination, and abnormal results in 24-hour images should be confirmed by using 99mTc-bone-metabolic imaging. 99mTc-ciprofloxacin yielded almost equally good results as 99mTc-leukocyte/bone-metabolic imaging, but unfortunately, the tracer is not commercially available, although it has been patented.
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La persuasión del discurso publicitario en el empaque y etiquetado de productos en un mercado saturado / The persuasion of the advertising discourse in the packaging and labeling of products in a saturated marketGarcía Gallo, Paola Andrea 17 November 2019 (has links)
El uso del empaque y/o etiquetado en estos últimos años se ha convertido en algo más que un objeto que protege el producto, ya que ha pasado de ser una parte importante del marketing del producto a comunicar el discurso publicitario de una marca. Esto se debe a que, así como “protege lo que vende” también “vende lo que protege” (Varela y Alonso, 2016). Sumándole el hecho de que hoy en día, las marcas viven en un contexto de mercado saturado, la cual se define como un espacio en donde conviven productos similares con empaques y precios similares. Cabe resaltar que dichos productos son denominados como “marca blanca”, los cuales están hechos de la misma calidad, pero a menor precio, de modo que no cuentan con alto costo de publicidad, ya que no necesitan de tano estímulo emocional por parte de sus consumidores al ser productos de consumo masivo y de básica necesidad (Bertomeu y Fortín, 2016). Por ende, en muchos casos el empaque se convierte en su única publicidad (Santa María, 2014). Esto hace conveniente determinar qué característica del empaque le permite a la marca sobresalir de su competencia. Debido a ello, es relevante saber de los elementos que la conforman y cuales son lo más identificados por el consumidor a tal punto que motive su compra (Mohebbi, 2014). El objetivo general de este artículo es analizar la jerarquización de los mensajes que se presenta en el empaquetado y etiquetado del producto. Esto se va a determinar a través de un enfoque cualitativo, por medio de entrevistas personales a profesionales del tema y entrevistas grupales a audiencias, a través de un muestreo por conveniencia. Cabe resaltar que el grupo estará conformado por grupos de hombres y mujeres entre el rango de edad 18 a 25 años, de un nivel socioeconómico A y B de la ciudad de Lima. Es importante mencionar que el empaque estudiado será de la categoría de alimentos conservados, específicamente, las latas de atún. Las marcas estudiadas serán: Mass, Compass y Fanny. Estas son marcas de atunes de baja exposición publicitarias y con los mismos precios en el mercado. Cabe resaltar que posee empaques similares distinguidos por su común color rojo. / The use of packaging and / or labeling in recent years has become more than just an object that protects the product, since it has gone from being an important part of product marketing to communicating the advertising discourse of a brand. This is because, just as it “protects what it sells” it also “sells what it protects” (Varela and Alonso, 2016). In addition to the fact that today, brands live in a saturated market context, which is defined as a space where similar products with similar packaging and prices coexist. It should be noted that these products are called "white label", which are made of the same quality, but at a lower price, so that they do not have a high advertising cost, since they do not need so much emotional stimulation from their customers. consumers as they are products of mass consumption and basic necessity (Bertomeu and Fortín, 2016). Therefore, in many cases the packaging becomes their only advertisement (Santa María, 2014). This makes it convenient to determine what characteristic of the packaging allows the brand to stand out from its competition. Due to this, it is relevant to know about the elements that make it up and which ones are most identified by the consumer to the point that it motivates their purchase (Mohebbi, 2014). The general objective of this article is to analyze the hierarchy of the messages that is presented in the packaging and labeling of the product. This will be determined through a qualitative approach, through personal interviews with professionals on the subject and group interviews with audiences, through convenience sampling. It should be noted that the group will be made up of groups of men and women between the age range 18 to 25 years, of a socioeconomic level A and B of the city of Lima. It is important to mention that the packaging studied will be from the category of preserved foods, specifically, tuna cans. The brands studied will be: Mass, Compass and Fanny. These are brands of tuna with low advertising exposure and with the same prices in the market. It should be noted that it has similar packaging distinguished by its common red color. / Trabajo de investigación
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Analysis and coordination of mixed-criticality cyber-physical systemsMaurer, Simon January 2018 (has links)
A Cyber-physical System (CPS) can be described as a network of interlinked, concurrent computational components that interact with the physical world. Such a system is usually of reactive nature and must satisfy strict timing requirements to guarantee a correct behaviour. The components can be of mixed-criticality which implies different progress models and communication models, depending whether the focus of a component lies on predictability or resource efficiency. In this dissertation I present a novel approach that bridges the gap between stream processing models and Labelled Transition Systems (LTSs). The former offer powerful tools to describe concurrent systems of, usually simple, components while the latter allow to describe complex, reactive, components and their mutual interaction. In order to achieve the bridge between the two domains I introduce the novel LTS Synchronous Interface Automaton (SIA) that allows to model the interaction protocol of a process via its interface and to incrementally compose simple processes into more complex ones while preserving the system properties. Exploiting these properties I introduce an analysis to identify permanent blocking situations in a network of composed processes. SIAs are wrapped by the novel component-based coordination model Process Network with Synchronous Communication (PNSC) that allows to describe a network of concurrent processes where multiple communication models and the co-existence and interaction of heterogeneous processes is supported due to well defined interfaces. The work presented in this dissertation follows a holistic approach which spans from the theory of the underlying model to an instantiation of the model as a novel coordination language, called Streamix. The language uses network operators to compose networks of concurrent processes in a structured and hierarchical way. The work is validated by a prototype implementation of a compiler and a Run-time System (RTS) that allows to compile a Streamix program and execute it on a platform with support for ISO C, POSIX threads, and a Linux operating system.
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Studies on Retinal Circulation in Experimental Animals, Healthy Human Eyes and Eyes with Diabetic RetinopathyTomić, Lidija January 2008 (has links)
The retina is a highly metabolically active tissue with large demands on the supply of nutrients. Disorders affecting the retina often include some vasculopathy with an impact on retinal circulation. Studies of retinal haemodynamics could thus help to detect, differentiate and diagnose diseases, to monitor changes in disease as well as progression and efficiency of the therapy. The present studies were an attempt to validate and determine the clinical usefulness of a newly developed technique for studying the retinal circulation in human eyes. We used different techniques to evaluate different parameters of retinal circulation. We examined how leukocyte velocity determined with Blue Field Simulation and transit times, mean transite time (MTT) and arterio-venous passage (AVP), and vessel diameter, determined from fluorescein angiograms, together reflects the retinal circulation. MTT was determined with a method based on an Impulse-Response technique, MTTIR. In a study on monkeys we compared our method, together with two conventional methods, with an absolute measurement of retinal blood flow (RBF) determined with labelled microspheres. There was a weak, but not statistically significant, correlation between retinal blood flow and MTTIR (r2 = -0.60, p = 0.06), but no useful correlation between retinal blood flow and either of the other two measures of transit times. In a study on healthy eyes we determined the effect of a physiological provocation, changes in arterial blood gases, on retinal circulation. Breathing pure oxygen or increased level of carbon dioxide in inspired air had no effect on MTT, but oxygen reduced leukocyte velocity and vessel diameter and carbon dioxide increased leukocyte velocity significantly. We concluded that unchanged transit time trough the retinal tissue was not due to a lack of effect of the gas provocation but a result due to concomitant changes in volume and flow. In a study on eyes of patients with diabetic retinopathy we investigated the relation between the extent of retinal circulation changes and the severity of the diabetes retinopathy (DRP). Transit times were relatively unaffected until proliferative DRP (PDRP) developed. In eyes with PDRP both MTTIR and AVP were increased. After panretinal photocoagulation treatment MTTIR returned to normal levels and vessel diameters tended to decrease while leukocyte velocity and AVP remained unchanged. We concluded that the increase in MTTIR in eyes with PDRP is at least partly explained by vessel dilation, causing an increased volume of the retinal vascular bed.
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Proteome-wide Identification of New Molecular Targets Affected by Methotrexate in Acute Promyelocytic Leukaemia Cell Line / Proteome-wide Identification of New Molecular Targets Affected by Methotrexate in Acute Promyelocytic Leukaemia Cell LineAgarwal, Nitin Kumar 02 May 2007 (has links)
No description available.
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Biomass production and nutrient cycling in short-rotation coppice willow (Salix spp.) bioenergy plantations in Saskatchewan, Canada2013 December 1900 (has links)
Biomass energy is currently the largest renewable contributor to global energy supply and there is increasing demand for bioenergy feedstock. Consequently, the production of purpose-grown woody bioenergy crops, such as short rotation coppice (SRC) willow, is expected to proliferate. Although the economic and environmental benefits associated with SRC willow production are well documented, systematic assessments of nutrient cycling within these plantations are rare. The objective of this study was to examine biomass production and biogeochemical cycling of nitrogen (N), phosphorus (P), potassium (K), sulphur (S), calcium (Ca), and magnesium (Mg) during an initial four-year rotation of six willow varieties grown at four plantations along a 500 km north-south pedoclimatic gradient within Saskatchewan, Canada. Nutrient budgets were also calculated after quantifying various nutrient inputs (e.g., atmospheric deposition, soil mineral weathering, and organic matter mineralization), outputs (e.g., above- and below-ground biomass, leaching, and denitrification), and transfers (e.g., canopy exchange, leaf litter decomposition, and fine root turnover) affecting the plant available soil nutrient pool. Total stem, leaf litter, and below-ground (primarily fine roots) biomass production after four years averaged 19.0, 7.1, and 12.5 Mg ha-1, respectively, with corresponding soil nutrient budget deficits of 17, 39, 112, 271, and 74 kg ha-1 of N, P, K, Ca, and Mg, respectively, but a soil S surplus of 60 kg ha-1. Despite willow’s relatively low nutrient-demanding nature, negligible leaching and denitrification losses, and substantial nutrient cycling from leaf litter, the nutrient export in harvested biomass over multiple rotations will require soil nutrient amendments, particularly N and P, to maintain plantation productivity. Given the apparent eventual need for supplemental fertility to support adequate willow growth over the 22-yr plantation life span, the fate of broadcast 15N-labelled fertilizer was also examined. Though the willow accumulated less than ⅓ of the applied fertilizer N after one year, the majority of the residual fertilizer N (51%) remained available for willow uptake in subsequent years. Further research is needed to track the fate of applied fertilizers over multiple rotations to better understand fertilizer dynamics for optimizing SRC willow agronomy; thus helping to promote its viability as a biomass energy feedstock option.
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Photosynthetic capacity and nitrogen nutrition of Ecuadorian montane forest treesWittich, Bärbel 09 April 2013 (has links)
Mit zunehmender Meereshöhe werden die Wachstumsbedingungen in tropischen Bergregionen im Allgemeinen ungünstiger, was sich in einer sinkenden Nährstoffverfügbarkeit, sinkenden Temperaturen und sinkendem CO2-Partialdruck zeigt. In tropischen Bergregenwäldern führen verminderte Abbauraten in größeren Höhen einerseits zu dicken organische Auflageschichten und andererseits in Kombination mit verminderten Mineralisierungs- und Nitrifizierungsraten zu Veränderungen in der Verfügbarkeit der verschiedenen Stickstoffformen, und es gibt Nachweise einer Limitierung der Produktivität dieser Wälder durch Stickstoff. Auf welche Weise sich die Photosynthesekapazität (Amax) tropischer Bäume einerseits und die Stickstoffaufnahmekapazität und Präferenz für einzelne Stickstoffformen andererseits an die veränderten Umweltbedingungen entlang von Höhengradienten adaptieren ist nicht genau bekannt.
Die vorliegende Untersuchung wurde in drei tropischen Bergregenwäldern durchgeführt, die entlang eines Höhengradienten auf 1000, 2000 und 3000 m ü. NN in Südequador liegen. Das Ziel war es, (1) die Photosynthesekapazität ausgewachsener tropischer Bäume entlang eines Höhengradienten mit Hilfe von Gaswechselmessungen zu bestimmen und die Effekte von Temperatur, CO2-Partialdruck und Nährstoffverfügbarkeit auf die Photosynthese zu quantifizieren und (2) Veränderungen in der Verwendung von Nitrat, Ammonium und organischen Stickstoffquellen durch tropische Waldbäume mit der Meereshöhe mittels einer Tracer-Untersuchung mit stabilen Isotopen an Jungpflanzen zu untersuchen.
Mittelwerte der lichtgesättigten Photosyntheserate (Asat) auf Bestandeseben betrugen 8.8, 11.3 und 7.2 µmol CO2 m-2 s-1, die der Dunkelatmung (RD) 0.8, 0.6 und 0.7 µmol CO2 m-2 s-1 jeweils auf 1000, 2000 and 3000 m Meereshöhe, ohne einen signifikanten Höhentrend. Die Einordnung unserer Daten in den Kontext eines pantropischen Asat-Datensatzes von tropischen Bäumen (c. 170 Arten an 18 Standorten unterschiedlicher Meereshöhe) zeigte, dass das flächenbezogene Asat in tropischen Bergen im Mittel 1.3 µmol CO2 m-2 s-1 pro km Höhenzunahme abnimmt (bzw. 0.2 µmol CO2 m-2 s-1 pro K Temperaturabnahme). Die Abnahme von Asat trat auf, obwohl die Blattmasse je Fläche mit der Höhe zunahm. Eine verminderte Photosyntheserate und eine reduzierte Bestandesblattfläche bewirken gemeinsam eine Verringerung der Kohlenstoffaufnahme des Kronenraums mit der Meereshöhe in tropischen Bergregionen.
Der Phosphorgehalt pro Blattmasse war der Faktor, der Amax entlang des Höhengradienten hauptsächlich beeinflusste, während die Effekte von Blattstickstoff, Temperatur und CO2-Partialdruck nicht signifikant waren. Amax erfuhr einen teilweisen und RD einen vollständigen homöostatischen Ausgleich als Reaktion auf die Verminderung von Temperatur und CO2-Partialdruck in größeren Höhen, was hauptsächlich durch eine stark reduzierte spezifische Blattfläche (SLA) und die daraus entstehende Zunahme von Blattstickstoff und -phosphor je Blattfläche bedingt war, während keine Zunahme der Karboxylierungseffizienz festgestellt wurde. Wir schlussfolgern, dass die Verminderung von SLA und Gesamtblattfläche mit der Meereshöhe die Kohlenstoffaufnahme von tropischen Wäldern in großen Meereshöhen deutlich stärker bestimmen als adaptive physiologische Modifizierungen des Photsyntheseapparates.
Jungpflanzen von sechs Baumarten unterschieden sich hinsichtlich ihrer Präferenz für verschieden Stickstoffformen, allerdings schienen weder das Amonium- und Nitratvorkommen im Boden noch die Meereshöhe die Präferenz zu beeinflussen. Zwei Arten (jeweils die, mit den höchsten Wachstumsraten) bevorzugten Amonium gegenüber Nitrat, während die restlichen vier Arten Nitrat und Amonium mit ähnlichen Raten aufnahmen, wenn beide Stickstofformen verfügbar waren. Nach der Gabe von 15N13C-Glyzin zeigte sich bei drei Arten eine signifikante Akkumulierung von 13C in der Biomasse (zwei Arten mit arbuskulären Mykorrhiza und eine Art mit Ektomykorrhiza) zusätzlich zu einer signifikanten Akkumulierung von 15N, was darauf hindeutet, dass Bäume in tropischen Bergregenwäldern organische Stickstoffverbindungen unabhängig vom Typ ihrer Mykorrhizierung aufnehmen können.
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Capacité de deux accéléromètres (SenseWear Armband et l’Actical) à estimer la dépense énergétique totale chez les adultes sainsSangaré, Cheick Papa Oumar 01 1900 (has links)
L’augmentation de la dépense énergétique (DE) par une augmentation de l'activité physique (AP) participe au maintien et à l’amélioration de la santé. La mesure à grande échelle de la DE totale (DET) en général et AP en particulier se heurte à des difficultés pratiques de recueil de données, de validité et aux coûts. Bien que dans la littérature de nombreux accéléromètres permettent d’estimer la DET, il y a encore des limites quant à la mesure de l’intensité de l’AP, élément qui influence l’état de la balance énergétique et le bénéfice pour la santé de l’AP. De plus, peu de comparaisons entre les différents accéléromètres sont disponibles. La présente étude avait pour but d’évaluer la capacité de deux accéléromètres (Actical et Sensewear Armband) pour estimer la DET en comparaison avec la technique de l’eau doublement marquée (EDM) ; d’évaluer la concordance entre les accéléromètres dans la mesure de la DE au repos (DER) en comparaison avec la technique de la calorimétrie indirecte (CI) et d’évaluer la DE liée à l’AP en comparaison avec la technique de la CI. Les résultats montrent qu’il y a une très bonne corrélation entre la CI et les accéléromètres dans la mesure de la DER(r > 0.80, p<0.001) et une bonne corrélation entre les accéléromètres et l’EDM dans la mesure de la DET(r>0.75, p<0.001). Pour la mesure de l’intensité de l’AP, l’ACT est plus précis (r=0.80, p<0.001)) que le SWA à la marche, le SWA est meilleur(r=0.80, p<0.001) au vélo. Cette étude permet d’affirmer que le SWA et l’ACT sont des alternatives valables pour mesurer la DE. / The increase in energy expenditure by the increase of physical activity contributes to maintaining and improving health. The large-scale measurement of total energy expenditure in general and physical activity in particular, is faced with difficulties of data collection, validity and cost. Although literature suggests that many accelerometers are used to estimate total energy expenditure, there are still limits as to the measurement of the intensity of physical activity, which is one of the factors that influences the energy balance and health benefits of physical activity. In addition, few comparisons between the different accelerometers are available. This study aimed to evaluate the ability of two accelerometers (Actical and SensWear Armband) to estimate total energy expenditure compared with the technique of doubly labelled water; to assess the correlation between the two accelerometers in the measurement of resting energy expenditure, compared with the technique of indirect calorimetry and finally to assess energy expenditure linked to physical (walking and cycling) at different intensities, in comparison with the indirect calorimetry technique. The results show a very good correlation between indirect calorimetry and the two accelerometers(r > 0.80, p<0.001) in the measurement of resting energy expenditure and a good correlation between accelerometers and the gold standard technique (doubly labeled water) in the measurement of total energy expenditure(r>0.75, p<0.001). To measure the intensity of physical activity, Actical is more accurate than SensWear Armband(r=0.80, p<0.001) at low intensity while the SensWear Armband is better at higher intensity (r=0.80, p<0.001). This study provides evidence that these two accelerometers are suitable alternatives for measuring energy expenditure.
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