903 resultados para qualitative and quantitative methods
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Malgrat la rellevància estratègica i el paper desestabilitzador de Corea del Nord a la regió econòmicament més dinàmica del món, la UE no compta amb cap estratègia clara per involucrar-se amb aquest país. Combinant tècniques d’anàlisi qualitatives i quantitatives, aquest treball pretén descobrir possibles contradiccions internes que impedeixin la definició d'una política exterior europea coherent i efectiva amb respecte a Corea del Nord, així com discrepàncies entre les percepcions d’actors interns de la UE i les d’actors externs. S'han detectat importants diferències d’expectatives i mancances en termes de coherència, tant entre les visions expressades pels actors interns com entre les opinions d’aquests actors i les dels futurs líders sudcoreans enquestats – diferències que fins i tot afecten la promoció dels drets humans
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This article describes the composition of fingermark residue as being a complex system with numerous compounds coming from different sources and evolving over time from the initial composition (corresponding to the composition right after deposition) to the aged composition (corresponding to the evolution of the initial composition over time). This complex system will additionally vary due to effects of numerous influence factors grouped in five different classes: the donor characteristics, the deposition conditions, the substrate nature, the environmental conditions and the applied enhancement techniques. The initial and aged compositions as well as the influence factors are thus considered in this article to provide a qualitative and quantitative review of all compounds identified in fingermark residue up to now. The analytical techniques used to obtain these data are also enumerated. This review highlights the fact that despite the numerous analytical processes that have already been proposed and tested to elucidate fingermark composition, advanced knowledge is still missing. Thus, there is a real need to conduct future research on the composition of fingermark residue, focusing particularly on quantitative measurements, aging kinetics and effects of influence factors. The results of future research are particularly important for advances in fingermark enhancement and dating technique developments.
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Various compositions of synthetic calcium phosphates (CaP) have been proposed and their use has considerably increased over the past decades. Besides differences in physico-chemical properties, resorption and osseointegration, artificial CaP bone graft might differ in their resistance against biofilm formation. We investigated standardised cylinders of 5 different CaP bone grafts (cyclOS, chronOS (both β-TCP (tricalcium phosphate)), dicalcium phosphate (DCP), calcium-deficient hydroxyapatite (CDHA) and α-TCP). Various physico-chemical characterisations e.g., geometrical density, porosity, and specific surface area were investigated. Biofilm formation was carried out in tryptic soy broth (TSB) and human serum (SE) using Staphylococcus aureus (ATCC 29213) and S. epidermidis RP62A (ATCC 35984). The amount of biofilm was analysed by an established protocol using sonication and microcalorimetry. Physico-chemical characterisation showed marked differences concerning macro- and micropore size, specific surface area and porosity accessible to bacteria between the 5 scaffolds. Biofilm formation was found on all scaffolds and was comparable for α-TCP, chronOS, CDHA and DCP at corresponding time points when the scaffolds were incubated with the same germ and/or growth media, but much lower for cyclOS. This is peculiar because cyclOS had an intermediate porosity, mean pore size, specific surface area, and porosity accessible to bacteria. Our results suggest that biofilm formation is not influenced by a single physico-chemical parameter alone but is a multi-step process influenced by several factors in parallel. Transfer from in vitro data to clinical situations is difficult; thus, advocating the use of cyclOS scaffolds over the four other CaP bone grafts in clinical situations with a high risk of infection cannot be clearly supported based on our data.
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Résumé Les rongeurs utilisent leurs moustaches (vibrisses) pour explorer le milieu environnant. Chaque moustache est mue par un système des muscles. Les récepteurs situés à sa base transmettent les informations au système nerveux central. La transmission vers l'écorce se fait via trois neurones de relais qui se trouvent au niveau du ganglion trigéminé, du tronc cérébral et du thalamus. La représentation corticale d'une vibrisse est une concentration des axones thalamo-corticaux (ATC) autour desquelles s'organisent leurs cibles, les cellules de la couche IV. La structure peut être identifiée histologiquement en coupes tangentielles et porte le nom de « barrel » (« tonneau »). Cette correspondance vibrisse - barrel fait de ce système un model idéal pour étudier l'influence de l'activité périphérique sur l'établissement et le maintien des cartes somatotopiques. Notre laboratoire dispose d'une souche de souris qui a subi une mutation spontanée pour le gène codant l'adenylyl cyclase I (ACI). Cette enzyme membranaire catalyse la formation de l'AMPc et joue un rôle important dans le guidage axonal, la libération des neurotransmetteurs et l'intégration des signaux postsynaptiques. Nous avons démontré dans un premier temps que cette souris adulte ne développe pas de barrels. Cela est dû à un manque d'organisation des ATC et aussi des cellules de la couche IV. De plus, les résultats électrophysiologiques montrent que les informations venant des vibrisses adjacentes ne sont pas intégrées d'une manière normale. Dans ce travail de thèse, j'ai analysé la morphologie des ATC révélés individuellement avec de la biocytine. L'analyse quantitative des ATC a mis en évidence les points suivants: 1. Les axones de la souris normale (NOR) quittent le thalamus, traversent la capsule interne et la substance blanche sous-corticale et pénètrent dans le cortex somato-sensoriel primaire. A l'intérieur de l'écorce ils traversent au maximum 3 colonnes corticales adjacentes dont une contient le barrel cible. En passant à travers les couches VI et V, ces axones arborisent et convergent progressivement vers le barrel dans lequel ils forment une riche arborisation. Un petit nombre des branches « errantes », pleines de boutons synaptiques, pénètrent dans les barrels voisins. Deux axones NOR provenant de corps cellulaires très proches dans le thalamus peuvent avoir un cheminement très divergent lors de la traversée de la capsule interne et de la substance blanche sous-corticale mais, à leur entrée dans le cortex, ils sont distants d'au maximum 2 colonnes corticales de la colonne qui contient le barrel cible et ils convergent progressivement vers ce barrel. 2. Les axones de la souris mutante (BRL) ont le même trajet sous-cortical que les axones NOR, mais leur entrée dans le cortex somato-sensoriel primaire est aléatoire. A l'interface entre la substance blanche sous-corticale et le cortex, l'axone principal se divise rapidement en troncs axonaux qui traversent les couches VI et V d'une manière divergente pour arriver dans la couche IV. Cela contraste beaucoup avec la trajectoire des NOR qui convergent graduellement vers leur barrel cible. Le nombre de branches radiales que les axones BRL utilisent pour entrer dans le cortex et dans la couche IV est double par rapport aux axones NOR. Parmi ces branches, seules quelques-unes donnent des arborisations, les autres ne sont pas développées et leur morphologie est semblable à celle des branches formées par les axones de la souris normale lors du développement. Deux axones BRL issus de corps cellulaires proches dans le thalamus peuvent avoir une trajectoire très divergente jusqu'à leur entrée dans la couche IV, mais à ce niveau ils sont réorientés pour se retrouver et faire un nombre maximal de branches et boutons synaptiques dans la même région corticale. Dans un cas extrême, un des axones observés est entré dans le cortex à la limite entre l'aire somatosensorielle primaire et secondaire et a parcouru une distance de 2 mm pour retrouver son partenaire thalamique et donner avec celui-ci un nombre maximal de branches dans la même région de la couche IV. 3. Les mesures quantitatives ont montré que les arborisations corticales des axones NOR ont une longueur moyenne de 18mm et sont formées par 200 segments qui portent 1200 boutons synaptiques. Par rapport à la souris NOR, les axones BRL ont en moyenne la même longueur, le même nombre de segments et boutons synaptiques, mais donnent deux fois plus de branches radiales. La surface tangentielle occupée par les arborisations BRL dans la couche IV est 2 fois plus grande que celle des NOR. Cela signifie que les 1000 boutons synaptiques qui caractérisent les arborisations NOR et BRL dans la couche IV sont disséminés sur une surface tangentielle double chez les derniers, et donc que la densité des boutons par unité de surface corticale est en moyenne plus faible. En effet, l'augmentation de la surface corticale tangentielle des BRL est due aux surfaces de faible et moyenne densité synaptique (0 - 8 boutons / 400pn2) qui augmentent 2 fois tandis que les surfaces de haute densité synaptiques (8 - 64 boutons / 4001.tm2) sont les mêmes. Nous émettons l'hypothèse selon laquelle, durant le développement, les ATC de la souris BRL divergent et forment un nombre exubérant de branches. Grâce à cette divergence et aux branches supranuméraires, ils trouvent l'endroit de l'écorce où se trouvent leurs voisins thalamiques et arborisent abondamment dans cette région. Cependant, le déficit en AGI ne leurs permet pas par la suite, sous influence de l'activité périphérique, de retirer les branches qui se trouvent dans les endroits inappropriés de l'écorce, avec de possibles conséquences sur la discrimination tactile.
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The Kineticist's Workbench is a program that simulates chemical reaction mechanisms by predicting, generating, and interpreting numerical data. Prior to simulation, it analyzes a given mechanism to predict that mechanism's behavior; it then simulates the mechanism numerically; and afterward, it interprets and summarizes the data it has generated. In performing these tasks, the Workbench uses a variety of techniques: graph- theoretic algorithms (for analyzing mechanisms), traditional numerical simulation methods, and algorithms that examine simulation results and reinterpret them in qualitative terms. The Workbench thus serves as a prototype for a new class of scientific computational tools---tools that provide symbiotic collaborations between qualitative and quantitative methods.
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There is a substantial literature which suggests that appraisals are smoothed and lag the true level of prices. This study combines a qualitative interview survey of the leading fund manager/owners in the UK and their appraisers with a empirical study of the number of appraisals which change each month within the IPD Monthly Index. The paper concentrates on how the appraisal process operates for commercial property performance measurement purposes. The survey interviews suggest that periodic appraisal services are consolidating in fewer firms and, within these major firms, appraisers adopt different approaches to changing appraisals on a period by period basis, with some wanting hard transaction evidence while others act on "softer' signals. The survey also indicates a seasonal effect with greater effort and information being applied to annual and quarterly appraisals than monthly. The analysis of the appraisals within the Investment Property Databank Monthly Index confirms this effect with around 5% more appraisals being moved at each quarter day than the other months. January and August have significantly less appraisal changes than other months.
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There is a substantial literature which suggests that appraisals are smoothed and lag the true level of prices. This study combines a qualitative interview survey of the leading fund manager/owners in the UK and their appraisers with a empirical study of the number of appraisals which change each month within the IPD Monthly Index. The paper concentrates on how the appraisal process operates for commercial real estate performance measurement purposes. The survey interviews suggest that periodic appraisal services are consolidating in fewer firms and, within these major firms, appraisers adopt different approaches to changing appraisals on a period by period basis, with some wanting hard transaction evidence while others act on ‘softer’ signals. The survey also indicates a seasonal effect with greater effort and information being applied to annual and quarterly appraisals than monthly. The analysis of the appraisals within the IPD Monthly Index confirms this effect with around 5% more appraisals being moved at each quarter day than the other months. More November appraisals change than expected and this suggests that the increased information flows for the December end year appraisals are flowing through into earlier appraisals, especially as client/appraiser draft appraisal meetings for the December appraisals, a regular occurrence in the UK, can occur in November. January illustrates significantly less activity than other months, a seasonal effect after the exertions of the December appraisals.
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This paper presents the development of a rapid method with ultraperformance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) for the qualitative and quantitative analyses of plant proanthocyanidins directly from crude plant extracts. The method utilizes a range of cone voltages to achieve the depolymerization step in the ion source of both smaller oligomers and larger polymers. The formed depolymerization products are further fragmented in the collision cell to enable their selective detection. This UPLC-MS/MS method is able to separately quantitate the terminal and extension units of the most common proanthocyanidin subclasses, that is, procyanidins and prodelphinidins. The resulting data enable (1) quantitation of the total proanthocyanidin content, (2) quantitation of total procyanidins and prodelphinidins including the procyanidin/prodelphinidin ratio, (3) estimation of the mean degree of polymerization for the oligomers and polymers, and (4) estimation of how the different procyanidin and prodelphinidin types are distributed along the chromatographic hump typically produced by large proanthocyanidins. All of this is achieved within the 10 min period of analysis, which makes the presented method a significant addition to the chemistry tools currently available for the qualitative and quantitative analyses of complex proanthocyanidin mixtures from plant extracts.
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The 2024 and 7050 aluminium alloys used as aircraft components were subjected to laboratory corrosion tests in sodium chloride solution, Light-microscope examinations make it possible to characterise morphological aspects of the localised corrosion. Image analysis was used to determine both depth and width of pits over corroded surfaces. It has been concluded that the annealing could reduce the pit growth in both alloys, by means of grains recrystallization or recovery. The 2024 alloy also tends to present an exfoliation mechanism, mainly throughout non-recrystallized and recrystallized grain boundaries, increasing the width and sustaining the depth of pit cavities during exposition to saline atmosphere. SEM and EDS analysis reveal the morphology and elemental distribution of the corrosion products formed after immersion corrosion test. Some of these products were identified by X-ray diffraction analysis. For 2024, Al(OH)(3), MS(OH)(2) and Cu2O were found. AI(OH)(3) and Cu2O were also found in 7050 samples.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Anormalidades do filme lacrimal de cães podem ser classificadas quanto ao seu aspecto quantitativo, qualitativo ou ambos, sendo comumente observada na prática cotidiana. Intercorrências na produção de um ou mais componentes do filme lacrimal ensejam distúrbios oculares em graus variados, denominados ceratoconjuntivite seca. Diversas são as causas da ceratoconjuntivite seca em cães, mas a maioria dos casos é de caráter idiopático, estando associada à participação de linfócitos T. O diagnóstico em medicina veterinária é firmado com base nos valores obtidos pelo teste da lacrimal de Schirmer. O presente artigo objetiva revisar os aspectos relacionados à etiopatogenia e ao diagnóstico da ceratoconjuntivite seca em cães, assim como discutir novas modalidades terapêuticas para a doença.
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Most of the problems of endodontic origin have a bacterial etiological agent. Thus, there is a continued interest in seeking more effective chemical substances that can replace the camphorated paramonochiorophenol or antibiotics as intracanal medicaments. Among the possible substances, ozone has some interesting biological characteristics: bactericidal action, debriding effect, angiogenesis stimulation capacity and high oxidizing power. The purpose of this study was to chemically evaluate the presence of ozone in sunflower, castor, olive and almond oil, as well as in propylene glycol and byproducts of ozonation, such as formaldehyde. These compounds were ozonized, inserted into empty and sterile vials, and analyzed by testing the reaction between ozone and indigo, for determining the presence of ozone, and subjected to the chromotropic acid test for determining the presence of formaldehyde. It was observed complete absence of ozone in all samples tested and presence of formaldehyde. The bactericidal and healing action of ozonized oils could be attributed to products formed by the ozonation of mineral oils, such as formaldehyde, not to the ozone itself.