976 resultados para infrared qualitative analyses


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Infrared spectroscopy is a versatile technique used for qualitative and quantitative determination of all types of molecular species. As far as analysis of confined or flowing gases is concerned, different types of cell can be found in the market, but they are often very expensive. This study describes the construction of a very efficient gas cell with good reproducibility for qualitative infrared analysis of confined or flowing gases, using easily available and low-cost materials.

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Polymer binder modification with inorganic nanomaterials (NM) could be a potential and efficient solution to control matrix flammability of polymer concrete (PC) materials without sacrificing other important properties. Occupational exposures can occur all along the life cycle of a NM and “nanoproducts” from research through scale-up, product development, manufacturing, and end of life. The main objective of the present study is to analyse and compare different qualitative risk assessment methods during the production of polymer mortars (PM) with NM. The laboratory scale production process was divided in 3 main phases (pre-production, production and post-production), which allow testing the assessment methods in different situations. The risk assessment involved in the manufacturing process of PM was made by using the qualitative analyses based on: French Agency for Food, Environmental and Occupational Health & Safety method (ANSES); Control Banding Nanotool (CB Nanotool); Ecole Polytechnique Fédérale de Lausanne method (EPFL); Guidance working safely with nanomaterials and nanoproducts (GWSNN); Istituto Superiore per la Prevenzione e la Sicurezza del Lavoro, Italy method (ISPESL); Precautionary Matrix for Synthetic Nanomaterials (PMSN); and Stoffenmanager Nano. It was verified that the different methods applied also produce different final results. In phases 1 and 3 the risk assessment tends to be classified as medium-high risk, while for phase 2 the more common result is medium level. It is necessary to improve the use of qualitative methods by defining narrow criteria for the methods selection for each assessed situation, bearing in mind that the uncertainties are also a relevant factor when dealing with the risk related to nanotechnologies field.

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Purpose: Collaboration and interprofessional practices are highly valued in health systems everywhere, partly based on the rationale that they improve outcomes of care for people with complex health problems, such as low back pain. Research in the area of low back pain also supports the involvement of different health professionals in the interventions for people who present this condition. The aim of this studywas to identify factors influencing the interprofessional practices of physiotherapists working in private settings with people with low back pain. Relevance: Physiotherapists, like other health professionals, are encouraged to engage in interprofessional practices in their dailywork. However, to date, very little is known of their interprofessional practices, especially in private settings. Understanding physiotherapists' interprofessional practices and their influencing factors will notably advance knowledge relating to the organisation of physiotherapy services for people with low back pain. Participants: Participants in this study were 13 physiotherapists including 10 women and 3 men, having between 3 and 22 years of professional experience, and working in one of 10 regions of the Province of Quebec (Canada). In order to obtain maximal variation in the perspectives, participants were selected using a recruitment matrix including three criteria: duration of professional experience, work location, and physical proximity with other professionals. Methods: Thiswas a descriptive qualitative study using faceto- face semi-structured interviews as the main method of data collection. An interview guide was developed based on an evidence-derived frame of reference. Each interview lasted between 55 and 95 minutes and was transcribed verbatim. Analysis: Qualitative analyses took the form of content analysis, encompassing data coding and general thematic regrouping. NVivo version 8 was used to assist data organisation and analysis. Results: Multiple factors influencing the interprofessional practices of physiotherapists were identified. The main factors include the consulting person's health condition, the extent of knowledge on health professionals' roles and fields of practice, the proximity and availability of professional resources, as well as daily work schedules. Conclusions: Our findings highlight the influence of multiple factors on physiotherapists' interprofessional practices, including professional practice and organisational issues. However, further research on the interprofessional practices of physiotherapists is still required. Research priorities targeting the views of other health professionals, as well as those of services users, would enhance our comprehension of interprofessional practices of physiotherapists. Implications: This study provides new insights that improve our understanding of the interprofessional practices of physiotherapists working in private settings with people with low back pain, more specifically on the factors influencing these practices. Based on our findings, implementing changes such as improving current and future health professionals' knowledge of the fields and roles of other health professionals through training may contribute to positively influencing interprofessional practices. Keywords: Interprofessional practices; Private practice; Low back pain Funding acknowledgements: This research was supported in part by a B.E. Schnurr Memorial Fund Research Grant administered by the Physiotherapy Foundation of Canada, as well as from a clinical research partnership in physiotherapy between the Quebec Rehabilitation Research Network (REPAR) and the Ordre professionnel de la physiothérapie du Québec (OPPQ). KP received doctoral-level scholarships from the Canadian Institutes of Health Research (CIHR) and the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). CE Dionne is a FRSQ senior Research Scholar. Ethics approval: This project was approved by the ethics research committee of the Institut de réadaptation en déficience physique de Québec.

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For the last decade, high-resolution (HR)-MS has been associated with qualitative analyses while triple quadrupole MS has been associated with routine quantitative analyses. However, a shift of this paradigm is taking place: quantitative and qualitative analyses will be increasingly performed by HR-MS, and it will become the common 'language' for most mass spectrometrists. Most analyses will be performed by full-scan acquisitions recording 'all' ions entering the HR-MS with subsequent construction of narrow-width extracted-ion chromatograms. Ions will be available for absolute quantification, profiling and data mining. In parallel to quantification, metabotyping will be the next step in clinical LC-MS analyses because it should help in personalized medicine. This article is aimed to help analytical chemists who perform targeted quantitative acquisitions with triple quadrupole MS make the transition to quantitative and qualitative analyses using HR-MS. Guidelines for the acceptance criteria of mass accuracy and for the determination of mass extraction windows in quantitative analyses are proposed.

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Studies have proven that the agroforestry systems in the semi-arid region of the State of Ceará, Brazil, induce an increase in soil organic C levels. Notwithstanding, there is no information if this increase also results in qualitative changes in different pools of soil organic matter. The objective of this study was to verify the possible chemical and structural alterations in fulvic and humic acids of a Luvisol in areas adopting agroforestry, traditional intensive cultivation and native forest in a long-term experiment conducted in the semi-arid region of Ceará State, Brazil. The study was conducted in an experimental area of the National Goat Research Center (Embrapa) in Sobral, CE. The following treatments were evaluated: agrosilvopasture (AGP), silvopasture (SILV), intensive cultivation under fallow (ICF), and areas with native forest (NF). Soil fulvic and humic acids fractions were extracted from the 0-6 and 6-12 cm layers and characterized by elemental composition, thermogravimetry and infrared spectroscopy analyses. The elemental composition analysis of humic acids confirmed the data found for fulvic acids, showing reduction in the C, H and N levels, followed by an increase in O contents in the AGP and ICF treatments over SILV and NF. In all treatments, except to SILV in the 0-6 cm layer, the percentage of mass loss was highest (300-600 °C) for humic acids in the thermally most stable region. Despite the similarity between infrared spectra, soil fulvic acids in the SILV treatment extracted from 6-12 cm depth decrease the absorption bands at 1708 and 1408 cm-1 followed by an increase in the absorption band at 1608 cm-1 attributed to aromatic C=C groups. This behavior suggests an increase in the aromatic character of the structure. The AGP and ICF treatments, which increase the soil tilling, favored the maintenance of humic substances with a more aromatic character in the soil than SILV and NF. The less aromatic humic substances in the SILV treatment resulted in an increase of exchange sites of soil organic matter, indicating improved nutrient cycling and maintenance of productivity in the system.

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This study aimed to investigate what proportion of two household staples, soap and crispbread products, in two Swedish supermarkets had English product names or descriptions, and attempted a qualitative analysis of the English language used. Out of the Swedish brands, 54-62% of the soap products had names and/or product descriptions containing English, compared to 13-15% of the crispbread; these differences were in line with previous research, suggesting English is used more to market certain product groups than other ones. Earlier studies have also proposed that English could be considered an ‘elite’ language in Sweden, and it might thus be more commonly found on more exclusive/expensive products, or in the supermarket primarily aiming at higher-income customers. However, the differences between the two supermarkets, and between the more and less expensive products, were not great enough for any firm conclusions. When products had a mixture of languages on the label, English was most often used for product names or part of names, not so often for product descriptions. Further studies with a larger amount of data would be required for more reliable conclusions, especially for the qualitative analyses. It would also be interesting to investigate customers’ attitudes towards the use of English on product labels.

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Ce travail de thèse présente deux grands axes. Le premier axe, touche les traitements du bois dans le but principal de réduire les variations dimensionnelles et d’améliorer la résistance à l’attaque des champignons lignivores. Le second axe quant à lui, touche l’aspect environnemental du traitement acide citrique-glycérol. Ce dernier a pour but principal de démontrer que le prolongement de la durée de vie en service du produit lambris traité, compense les impacts environnementaux causés par ce traitement. Dans le premier axe, deux traitements ont été réalisés sur deux essences de pin (Pinus strobus L. et Pinus contorta D.). Un traitement à l’anhydride maléique et un autre traitement avec une solution d’acide citrique – glycérol brute (AC-G). Dans le premier cas, les effets de deux paramètres (la durée de séchage et la température d’estérification) sur les résultats des essais de stabilité dimensionnelle, de résistance à la dégradation fongique et de vieillissement accéléré ont été évalués. Trois niveaux de durée de séchage après imprégnation (12 h, 18 h et 24 h) et trois niveaux de température d’estérification (140 °C, 160 °C et 180 °C) ont été considérés. Dans le second cas, après identification du meilleur catalyseur (HCl) et du meilleur ratio acide citrique – glycérol (3/1) pendant les essais préliminaires, les performances de ce traitement sur la stabilité dimensionnelle, la résistance à la pourriture fongique, la dureté de surface et l’adhérence des couches de revêtement de peinture sur la surface du substrat bois ont été analysées. Les résultats obtenus ont été appuyés par une suite d’analyses qualitatives et quantitatives pour mieux comprendre et expliquer. Les analyses qualitatives sont : (i) la spectroscopie infrarouge à transformée de Fourier (IRTF) et (ii) la microscopie électronique à balayage (MEB) tandis que la quantitative, l’analyse par perte de masse a été faite par pesée. Dans le second axe, une analyse des impacts environnementaux du traitement AC-G a été effectuée par le biais du logiciel SimaPro v8. La base de données Ecoinvent v3 et la méthode d’analyse d’impact Impact 2002+ ont été utilisées dans cette partie du travail de thèse. Sur la base des résultats du second traitement (AC-G) et des travaux disponibles dans la littérature, nous avons estimé, une durée de vie en service des lambris traités. Les différents scénarios de la durée de vie du lambris traité mis sur pied par rapport à celle offerte aujourd’hui par l’industrie, nous permettent de modéliser les impacts environnementaux du traitement. A cette fin, l’analyse de cycle de vie (ACV) a été utilisée comme outil de conception. En conclusion, les paramètres, durée de séchage et température d’estérification influencent les résultats obtenus dans le cas du traitement du bois à l’anhydride maléique. La combinaison 24 h de séchage et 180 °C, température d’estérification, représente les paramètres qui offrent les meilleurs résultats de stabilité dimensionnelle, de résistance à la dégradation fongique et de vieillissement accéléré. Le traitement AC-G améliore la stabilité dimensionnelle, la résistance à la dégradation fongique et la dureté de surface des échantillons. Cependant, le traitement réduit l’adhérence des couches de peinture. Les impacts environnementaux produits par le traitement AC-G sont majoritairement liés à la consommation de la ressource énergie (électricité). Le traitement prolonge la durée de vie en service du lambris traité et il a été mis en évidence que le scénario de durée de vie qui permettrait que le lambris traité puisse se présenter comme un produit à faible impact environnemental par rapport au lambris non traité est celui d’une durée de vie de 55 ans.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Phytoplankton may function as a "sensor" of changes in aquatic environment and responds rapidly to such changes. In freshwaters, coexistence of species that have similar ecological requirements and show the same environmental requirements frequently occurs; such species groups are named functional groups. The use of phytoplankton functional groups to evaluate these changes has proven to be very useful and effective. Thus, the aim of this study was to evaluate the occurrence of functional groups of phytoplankton in two reservoirs (Billings and Guarapiranga) that supply water to millions of people in São Paulo city Metropolitan Area, southeastern Brazil. Surface water samples were collected monthly and physical, chemical and biological (quantitative and qualitative analyses of the phytoplankton) were performed. The highest biovolume (mm³.L-1) of the descriptor species and functional groups were represented respectively by Anabaena circinalis Rabenh. (H1), Microcystis aeruginosa (Kützing) Kützing (L M/M) and Mougeotia sp. (T) in the Guarapiranga reservoir and Cylindrospermopsis raciborskii (Wolosz.) Seen. and Subba Raju (S N), Microcystis aeruginosa and M. panniformis Komárek et al. (L M/M), Planktothrix agardhii (Gom.) Anagn. and Komárek and P. cf. clathrata (Skuja) Anagn. and Komárek (S1) in the Billings reservoir. The environmental factors that most influenced the phytoplankton dynamics were water temperature, euphotic zone, turbidity, conductivity, pH, dissolved oxygen, nitrate and total phosphorous.

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A comunidade fitoplanctônica pode funcionar como sensor das variações do ambiente aquático respondendo rapidamente as essas alterações. Em sistemas aquáticos continentais é comum a coexistência de espécies que possuem as mesmas necessidades ecológicas e apresentam as mesmas tolerâncias ambientais, tais grupos de espécies fitoplanctônicas são denominados grupos funcionais. O uso de grupos funcionais fitoplanctônicos para avaliar tais alterações tem se mostrado muito útil e eficaz. Assim, o objetivo do estudo foi avaliar a ocorrência de grupos funcionais fitoplanctônicos em dois reservatórios (Billings e Guarapiranga) que suprem de água milhões de pessoas na Região Metropolitana de São Paulo, Sudeste do Brasil. As amostras foram coletadas mensalmente na superfície da coluna d'água e foram analisadas as variáveis físicas, químicas e biológicas (análises qualitativa e quantitativa do fitoplâncton). Os maiores valores de biovolume (mm3.L-1) das espécies descritoras e grupos funcionais foram representados por Anabaena circinalis (H1), Microcystis aeruginosa (LM/M) e Mougeotia sp. (T) no Reservatório Guarapiranga e por Cylindrospermopsis raciborskii (SN), Microcystis aeruginosa e M. panniformis (LM/M), Planktothrix agardhii e P. cf. clathrata (S1) no Reservatório Billings. Os principais fatores ambientais que interferiram na dinâmica do fitoplâncton foram: temperatura da água, zona eufótica, turbidez, condutividade, pH, oxigênio dissolvido, nitrato e fósforo total

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This work presents the analysis of nonlinear aeroelastic time series from wing vibrations due to airflow separation during wind tunnel experiments. Surrogate data method is used to justify the application of nonlinear time series analysis to the aeroelastic system, after rejecting the chance for nonstationarity. The singular value decomposition (SVD) approach is used to reconstruct the state space, reducing noise from the aeroelastic time series. Direct analysis of reconstructed trajectories in the state space and the determination of Poincare sections have been employed to investigate complex dynamics and chaotic patterns. With the reconstructed state spaces, qualitative analyses may be done, and the attractors evolutions with parametric variation are presented. Overall results reveal complex system dynamics associated with highly separated flow effects together with nonlinear coupling between aeroelastic modes. Bifurcations to the nonlinear aeroelastic system are observed for two investigations, that is, considering oscillations-induced aeroelastic evolutions with varying freestream speed, and aeroelastic evolutions at constant freestream speed and varying oscillations. Finally, Lyapunov exponent calculation is proceeded in order to infer on chaotic behavior. Poincare mappings also suggest bifurcations and chaos, reinforced by the attainment of maximum positive Lyapunov exponents. Copyright (C) 2009 F. D. Marques and R. M. G. Vasconcellos.

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Purpose: The double system of support, in which the distal-extension removable partial denture adapts, causes inadequate stress around abutment teeth, increasing the possibility of unequal bone resorption. Several ways to reduce or more adequately distribute the stress between abutment teeth and residual ridges have been reported; however, there are no definitive answers to the problem. The purpose of this study was to analyze, by means of photoelasticity, the most favorable stress distribution using three retainers: T bar, rest, proximal plate, I bar (RPI), and circumferential with mesialized rest. Materials and Methods: Three photoelastic models were made simulating a Kennedy Class II inferior arch. Fifteen dentures with long saddles, five of each design, were adjusted to the photoelastic patterns and submitted first to uniformly distributed load, and then to a load localized on the last artificial tooth. The saddles were then shortened and the tests repeated. The quantitative and qualitative analyses of stress intensity were done manually and by photography, respectively. For intragroup analyses the Wilcoxon test for paired samples was used, while for intergroup analyses Friedman and Wilcoxon tests were used to better identify the differences (p < 0.05). Results: The RPI retainer, followed by the T bar, demonstrated the best distribution of load between teeth and residual ridge. The circumferential retainer caused greater concentration of stress between dental apexes. Stress distribution was influenced by the type of retainer, the length of the saddle, and the manner of load application. Conclusions: The long saddles and the uniformly distributed loads demonstrated better distribution of stress on support structures.

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With over 80 000 described species, Brachycera represent one of the most diverse clades of organisms with a Mesozoic origin. Larvae of the majority of early lineages are detritivores or carnivores. However, Brachycera are ecologically innovative and they now employ a diverse range of feeding strategies. Brachyceran relationships have been the subject of numerous qualitative analyses using morphological characters. These analyses are often based on characters from one or a few character systems and general agreement on relationships has been elusive. In order to understand the evolution of basal brachyceran lineages, 101 discrete morphological characters were scored and compiled into a single data set. Terminals were scored at the family level, and the data set includes characters from larvae, pupae and adults, internal and external morphology, and male and female terminalia. The results show that all infraorders of Brachycera are monophyletic, but there is little evidence for relationships between the infraorders. Stratiomyomorpha, Tabanomorpha, and Xylophagomorpha together form the sister group to Muscomorpha. Xylophagomorpha and Tabanomorpha are sister groups. Within Muscomorpha, the paraphyletic Nemestrinoidea form the two most basal lineages. There is weak evidence for the monophyly of Asiloidea, and Hilarimorphidae appear to be more closely related to Eremoneura than other muscomorphs. Apsilocephalidae, Scenopinidae and Therevidae form a clade of Asiloidea. This phylogenetic evidence is consistent with the contemporaneous differentiation of the main brachyceran lineages in the early Jurassic. The first major radiation of Muscomorpha were asiloids and they may have diversified in response to the radiation of angiosperms in the early Cretaceous.

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Purpose – Castings defects are usually easy to characterize, but to eradicate them can be a difficult task. In many cases, defects are caused by the combined effect of different factors, whose identification is often difficult. Besides, the real non-quality costs are usually unknown, and even neglected. This paper aims to describe the development of a modular tool for quality improvement in foundries, and its main objective is to present the application potential and the foundry process areas that are covered and taken into account. Design/methodology/approach – The integrated model was conceived as an expert system, designated Qualifound, which performs both qualitative and quantitative analyses. For the qualitative analyses mode, the nomenclature and the description of defects are based on the classification suggested by the International Committee of the Foundry Technical Association. Thus, a database of defects was established, enabling one to associate the defects with the relevant process operations and the identification of their possible causes. The quantitative analysis mode deals with the number of produced and rejected castings and includes the calculation of the non-quality costs. Findings – The validation of Qualifound was carried out in a Portuguese foundry, whose quality system had been certified according to the ISO 9000 standards. Qualifound was used in every management area and it was concluded that the application had the required technological requisites to provide the necessary information for the foundry management to improve process quality. Originality/value – The paper presents a successful application of an informatics tool on quality improvement in foundries.

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Baseado na análise qualitativa de processos observados em grupos de crianças, este artigo dá ênfase à importância dos pares dos grupos de crianças, não só para a formação das posteriores competências de relacionamento em grupo, mas também para a capacidade fundamental de sentir empatia e para o desenvolvimento cognitivo. O meio de expressão mais importante nos grupos de crianças é o desempenho de papéis (o faz de conta). Mesmo tratando-se de situações de fantasia, as crianças também aproveitam estas situações para representar a dinâmica familiar e os papéisdos sexos, usando o grupo para se determinarem como sujeitos sociais. No que diz respeito ao desenvolvimento cognitivo, aprendem a movimentar-se entre as esferas da brincadeira, nãobrincadeira e metacomunicação. É aqui demonstrado em que idades as crianças possuem a capacidade para trabalhar com grupos de outras crianças, durante um longo período de tempo, e como é que os educadores as podem ajudar a desenvolver esta capacidade.