956 resultados para Multi-dimensional gas chromatography
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Stimulants are banned in-competition for all categories of sports by the World Anti-Doping Agency. A simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay employing electrospray ionisation in positive mode was developed in that work for the quantification in urine specimens of 4-methyl-2-hexaneamine, a primary amine exhibiting sympathomimetic properties. Following a simple pretreatment procedure, the analyte was separated using a gradient mobile phase on reverse phase C8 column. Selected reaction monitoring m/z 116.2-->57.3 was specific for detection of 4-methyl-2-hexaneamine and the assay exhibited a linear dynamic range of 50-700 ng/mL. The validated method has been successfully applied to analyze the target compound in food supplements as well as in urine specimens. The administered drug (40 mg) was detected at the level of 350 ng/mL in the urine up to 4 days.
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Many people worldwide live with a disability, i.e. limitations in functioning. The prevalence is expected to increase due to demographic change and the growing importance of non-communicable disease and injury. To date, many epidemiological studies have used simple dichotomous measures of disability, even though the WHO's International Classification of Functioning, Disability, and Health (ICF) provides a multi-dimensional framework of functioning. We aimed to examine associations of socio-economic status (SES) and social integration in 3 core domains of functioning (impairment, pain, limitations in activity and participation) and perceived health. We conducted a secondary analysis of representative cross-sectional data of the Swiss Health Survey 2007 including 10,336 female and 8,424 male Swiss residents aged 15 or more. Guided by a theoretical ICF-based model, 4 mixed effects Poisson regressions were fitted in order to explain functioning and perceived health by indicators of SES and social integration. Analyses were stratified by age groups (15-30, 31-54, ≥55 years). In all age groups, SES and social integration were significantly associated with functional and perceived health. Among the functional domains, impairment and pain were closely related, and both were associated with limitations in activity and participation. SES, social integration and functioning were related to perceived health. We found pronounced social inequalities in functioning and perceived health, supporting our theoretical model. Social factors play a significant role in the experience of health, even in a wealthy country such as Switzerland. These findings await confirmation in other, particularly lower resourced settings.
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L'exposition aux poussières de bois est associé à un risque accru d'adénocarcinomes des fosses nasales et des sinus paranasaux (SNC, 'Sinonasal cancer') chez les travailleurs du bois. Les poussières de bois sont ainsi reconnues comme cancérogènes avérés pour l'homme par le Centre international de Recherche sur le Cancer (CIRC). Toutefois, l'agent causal spécifique et le mécanisme sous-jacent relatifs au cancer lié aux poussières de bois demeurent inconnus. Une possible explication est une co-exposition aux poussières de bois et aux Hydrocarbures Aromatiques Polycycliques (HAP), ces derniers étant potentiellement cancérogènes. Dans les faits, les travailleurs du bois sont non seulement exposés aux poussières de bois naturel, mais également à celles générées lors d'opérations effectuées à l'aide de machines (ponceuses, scies électriques, etc.) sur des finitions de bois (bois traités) ou sur des bois composites, tels que le mélaminé et les panneaux de fibres à densité moyenne (MDF, 'Medium Density Fiberboard'). Des HAP peuvent en effet être générés par la chaleur produite par l'utilisation de ces machines sur la surface du bois. Les principaux objectifs de cette thèse sont les suivants: (1) quantifier HAP qui sont présents dans les poussières générées lors de diverses opérations courantes effectuées sur différents bois (2) quantifier l'exposition individuelle aux poussières de bois et aux HAP chez les travailleurs, et (3) évaluer les effets génotoxiques (dommages au niveau de l'ADN et des chromosomes) due à l'exposition aux poussières de bois et aux HAP. Cette thèse est composée par une étude en laboratoire (objectif 1) et par une étude de terrain (objectifs 2 et 3). Pour l'étude en laboratoire, nous avons collecté des poussières de différents type de bois (sapin, MDF, hêtre, sipo, chêne, bois mélaminé) générées au cours de différentes opérations (comme le ponçage et le sciage), et ceci dans une chambre expérimentale et dans des conditions contrôlées. Ensuite, pour l'étude de terrain, nous avons suivi, dans le cadre de leur activité professionnelle, 31 travailleurs de sexe masculin (travailleurs du bois et ébenistes) exposés aux poussières de bois pendant deux jours de travail consécutifs. Nous avons également recruté, comme groupe de contrôle, 19 travailleurs non exposés. Pour effectuer une biosurveillance, nous avons collecté des échantillons de sang et des échantillons de cellules nasales et buccales pour chacun des participants. Ces derniers ont également rempli un questionnaire comprenant des données démographiques, ainsi que sur leur style de vie et sur leur exposition professionnelle. Pour les travailleurs du bois, un échantillonnage individuel de poussière a été effectué sur chaque sujet à l'aide d'une cassette fermée, puis nous avons évalué leur exposition à la poussière de bois et aux HAP, respectivement par mesure gravimétrique et par Chromatographie en phase gazeuse combinée à la spectrométrie de masse. L'évaluation des dommages induits à l'ADN et aux chromosomes (génotoxicité) a été, elle, effectuée à l'aide du test des micronoyaux (MN) sur les cellules nasales et buccales et à l'aide du test des comètes sur les échantillons de sang. Nos résultats montrent dans la poussière de la totalité des 6 types de bois étudiés la présence de HAP (dont certains sont cancérogènes). Des différences notoires dans les concentrations ont été néanmoins constatées en fonction du matériau étudié : les concentrations allant de 0,24 ppm pour la poussière de MDF à 7.95 ppm pour le mélaminé. Nos résultats montrent également que les travailleurs ont été exposés individuellement à de faibles concentrations de HAP (de 37,5 à 119,8 ng m-3) durant les opérations de travail du bois, alors que les concentrations de poussières inhalables étaient relativement élevés (moyenne géométrique de 2,8 mg m-3). En ce qui concerne la génotoxicité, les travailleurs exposés à la poussière de bois présentent une fréquence significativement plus élevée en MN dans les cellules nasales et buccales que les travailleurs du groupe témoin : un odds ratio de 3.1 a été obtenu pour les cellules nasales (IC 95% : de 1.8 à 5.1) et un odds ratio de 1,8 pour les cellules buccales (IC 95% : de 1.3 à 2.4). En outre, le test des comètes a montré que les travailleurs qui ont déclaré être exposés aux poussières de MDF et/ou de mélaminé avaient des dommages à l'ADN significativement plus élevés que les deux travailleurs exposés à la poussière de bois naturel (sapin, épicéa, hêtre, chêne) et que les travailleurs du groupe témoin (p <.01). Enfin, la fréquence des MN dans les cellules nasales et buccales augmentent avec les années d'exposition aux poussières de bois. Par contre, il n'y a pas de relation dose-réponse concernant la génotoxicité due à l'exposition journalière à la poussière et aux HAP. Cette étude montre qu'une exposition aux HAP eu bien lieu lors des opérations de travail du bois. Les travailleurs exposés aux poussières de bois, et donc aux HAP, courent un risque plus élevé (génotoxicité) par rapport au groupe témoin. Étant donné que certains des HAP détectés sont reconnus potentiellement cancérogènes, il est envisageable que les HAP générés au cours du travail sur les matériaux de bois sont un des agents responsables de la génotoxicité de la poussière de bois et du risque élevé de SNC observé chez les travailleurs du secteur. Etant donné la corrélation entre augmentation de la fréquence des MN, le test des micronoyaux dans les cellules nasales et buccales constitue sans conteste un futur outil pour la biosurveillance et pour la détection précoce du risque de SNC chez les travailleurs. - Exposures to wood dust have been associated with an elevated risk of adenocarcinomas of the Dasal cavity and the paranasal sinuses (sinonasal cancer or SNC) among wood workers. Wood dust is recognized as a human carcinogen by the International Agency for Research on Cancer. However, the specific cancer causative agent(s) and the mechanism(s) behind wood dust related carcinogenesis remains unknown. One possible explanation is a co-exposure to wood dust and polycyclic aromatic hydrocarbons (PAH), the latter being carcinogenic. In addition, wood workers are not only exposed to natural wood but also to wood finishes and composite woods such as wood melamine and medium density fiber (MDF) boards during the manipulation with power tools. The heat produced by the use of power tools can cause the generation of PAH from wood materials. The main objectives of the present thesis are to: (1) quantify possible PAH concentrations in wood dust generated during various common woodworking operations using different wood materials; (2) quantify personal wood dust concentrations and PAH exposures among wood workers; and (3) assess genotoxic effects (i.e., DNA and chromosomal damage) of wood dust and PAH exposure in wood workers. This thesis is composed by a laboratory study (objective 1) and a field study (objectives 2 and 3). In the laboratory study we collected wood dust from different wood materials (fir, MDF, beech, mahagany, oak, and wood melamine) generated during different wood operations (e.g., sanding and sawing) in an experimental chamber under controlled conditions. In the following field study, we monitored 31 male wood workers (furniture and construction workers) exposed to wood dust during their professional activity for two consecutive work shifts. Additionally, we recruited 19 non exposed workers as a control group. We collected from each participant blood samples, and nasal and buccal cell samples. They answered a questionnaire including demographic and life-style data and occupational exposure (current and past). Personal wood dust samples were collected using a closed-face cassette. We used gravimetrie analysis to determine the personal wood dust concentrations and capillary gas chromatography - mass spectrometry analysis to determine PAH concentrations. Genotoxicity was assessed with the micronucleus (MN) assay for nasal and buccal cells and with the comet assay for blood samples. Our results show that PAH (some of them carcinogenic) were present in dust from all six wood materials tested, yet at different concentrations depending on the material. The highest concentration was found in dust from wood melamine (7.95 ppm) and the lowest in MDF (0.24 ppm). Our results also show that workers were individually exposed to low concentrations of PAHs (37.5-119.8 ng m"3) during wood working operations, whereas the concentrations of inhalable dust were relatively high (geometric mean 2.8 mg m"3). Concerning the genotoxicity, wood workers had a significantly higher MN frequency in nasal and buccal cells than the workers in the control group (odds ratio for nasal cells 3.1 (95%CI 1.8-5.1) and buccal cells 1.8 (95%CI 1.3-2.4)). Furthermore, the comet assay showed that workers who reported to be exposed to dust from wooden boards (MDF and wood melamine) had significantly higher DNA damage than both the workers exposed to natural woods (fir, spruce, beech, oak) and the workers in the control group (p < 0.01). Finally, MN frequency in nasal and buccal cells increased with increasing years of exposure to wood dust. However, there was no genotoxic dose-response relationship with the per present day wood dust and PAH exposure. This study shows that PAH exposure occurred during wood working operations. Workers exposed to wood dust, and thus to PAH, had a higher risk for genotoxicity compared to the control group. Since some of the detected PAH are potentially carcinogenic, PAH generated from operations on wood materials may be one of the causative agents for the observed increased genotoxicity in wood workers. Since increased genotoxicity is manifested in an increased MN frequency, the MN assay in nasal and buccal cells may become a relevant biomonitoring tool in the future for early detection of SNC risk.
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A cross-over controlled administration study of smoked cannabis was carried out on occasional and heavy smokers. The participants smoked a joint (11 % Δ9-tetrahydrocannabinol (THC)) or a matching placebo on two different occasions. Whole blood (WB) and oral fluid (OF) samples were collected before and up to 3.5 h after smoking the joints. Pharmacokinetic analyses were obtained from these data. Questionnaires assessing the subjective effects were administered to the subjects during each session before and after the smoking time period. THC, 11-hydroxy-THC (11-OH-THC) and 11-nor-9-carboxy-THC (THCCOOH) were analyzed in the blood by gas chromatography or liquid chromatography (LC)-tandem mass spectrometry (MS/MS). The determination of THC, THCCOOH, cannabinol (CBN), and Δ9-tetrahydrocannabinolic acid A (THC-A) was carried out on OF only using LC-MS/MS. In line with the widely accepted assumption that cannabis smoking results in a strong contamination of the oral cavity, we found that THC, and also THC-A, shows a sharp, high concentration peak just after smoking, with a rapid decrease in these levels within 3 h. No obvious differences were found between both groups concerning THC median maximum concentrations measured either in blood or in OF; these levels were equal to 1,338 and 1,041 μg/L in OF and to 82 and 94 μg/L in WB for occasional and heavy smokers, respectively. The initial WB THCCOOH concentration was much higher in regular smokers than in occasional users. Compared with the occasional smokers, the sensation of confusion felt by the regular smokers was much less while the feeling of intoxication remained almost unchanged.
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New products available for food creations include a wide variety of "supposed" food grade aerosol sprays. However, the gas propellants used cannot be considered as safe. The different legislations available did not rule any maximum residue limits, even though these compounds have some limits when used for other food purposes. This study shows a preliminary monitoring of propane, butane and dimethyl ether residues, in cakes and chocolate after spraying, when these gases are used as propellants in food aerosol sprays. Release kinetics of propane, butane and dimethyl ether were measured over one day with sprayed food, left at room temperature or in the fridge after spraying. The alkanes and dimethyl ether analyses were performed by headspace-gas chromatography-mass spectrometry/thermal conductivity detection, using monodeuterated propane and butane generated in situ as internal standards. According to the obtained results and regardingthe extrapolations of the maximum residue limits existing for these substances, different delays should be respected according to the storage conditions and the gas propellant to consume safely the sprayed food.
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Decisions taken in modern organizations are often multi-dimensional, involving multiple decision makers and several criteria measured on different scales. Multiple Criteria Decision Making (MCDM) methods are designed to analyze and to give recommendations in this kind of situations. Among the numerous MCDM methods, two large families of methods are the multi-attribute utility theory based methods and the outranking methods. Traditionally both method families require exact values for technical parameters and criteria measurements, as well as for preferences expressed as weights. Often it is hard, if not impossible, to obtain exact values. Stochastic Multicriteria Acceptability Analysis (SMAA) is a family of methods designed to help in this type of situations where exact values are not available. Different variants of SMAA allow handling all types of MCDM problems. They support defining the model through uncertain, imprecise, or completely missing values. The methods are based on simulation that is applied to obtain descriptive indices characterizing the problem. In this thesis we present new advances in the SMAA methodology. We present and analyze algorithms for the SMAA-2 method and its extension to handle ordinal preferences. We then present an application of SMAA-2 to an area where MCDM models have not been applied before: planning elevator groups for high-rise buildings. Following this, we introduce two new methods to the family: SMAA-TRI that extends ELECTRE TRI for sorting problems with uncertain parameter values, and SMAA-III that extends ELECTRE III in a similar way. An efficient software implementing these two methods has been developed in conjunction with this work, and is briefly presented in this thesis. The thesis is closed with a comprehensive survey of SMAA methodology including a definition of a unified framework.
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The aim of this study was to evaluate the reliability of insect larvae as samples for toxicological investigations. For this purpose, larvae of Lucilia sericata were reared on samples of minced pig liver treated with different concentrations of codeine: therapeutic, toxic, and potentially lethal doses. Codeine was detected in all tested larvae, confirming the reliability of these specimens for qualitative toxicology analysis. Furthermore, concentrations measured in larvae were correlated with levels in liver tissue. These observations bring new elements regarding the potential use of opiates concentrations in larvae for estimation of drug levels in human tissues. Morphine and norcodeine, two codeine metabolites, have been also detected at different concentrations depending on the concentration of codeine in pig liver and depending on the substance itself. The effects of codeine on the development of L. sericata were also investigated. Results showed that a 29-h interval bias on the evaluation of the larval stage duration calculated from the larvae weight has to be considered if codeine was present in the larvae substrate. Similarly, a 21-h interval bias on the total duration of development, from egg to imago, has to be considered if codeine was present in the larvae substrate.
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Työssä mitattiin työilman TBEP- ja TEHP-pitoisuuksia siivousalalla (3 kohdetta) ja muovituoteteollisuudessa (2 kohdetta). Pitoisuutta ilmassa verrattiin työntekijöidenbiomonitorointinäytteistä analysoitujen 2-butoksietikkahapon (2-BAA) ja 2-etyyliheksaanihapon (2-EHA) pitoisuuteen. Tavoitteena oli biomonitoroin-timenetelmän soveltuvuuden selvittäminen altistumisen arvioinnissa sekä tarvittavien lisäsuojaus- ja torjunta-tarpeiden selvittäminen. Biomonitorointia sekoittavien tekijöiden (2-butoksietanoli ja 2-etyyli-1-heksanoli) pitoisuus mitattiin työntekijöidenhengitysilmasta kerätystä VOC-näytteestä. OVS-keräimiin kerätyt TBEP- ja TEHP-näytteet uutettiin ultraäänellä sopivalla liuottimella ja analysoitiin kaasukromatografisesti (GC). VOC-näytteet kerättiin Tenax GR ¿adsorbenttiin, irrotettiin keräimestä termodesorptiolla ja analysoitiin GC:lla. Biomonitorointinäytteiden (virtsa) 2-BAA- ja 2-EHA -pitoisuus analysoitiin myös GC:lla. Lattianvahauksen aikana siivoojien hengitysilmasta mitatuissa TBEP-näytteissä pitoisuudet vaihtelivat välillä 70 - 860 ng/m3 sekä VOC-näytteistä 88 %:sta löytyi2-butoksietanolia, jonka pitoisuus vaihteli välillä 3 - 1800 µg/m3. Virtsan 2-BAA:n pitoisuudet vaihtelivat välillä <0,3 - 26 mmol/mol kreatiniinia ollen korkeimmillaan 43 % toimenpiderajasta. Raskaana olevien toimenpideraja ylitettiin 30 % näytteistä. Muovituotetehtaissa TEHP-pitoisuus työntekijöiden hengitysilmassa oli alle määritysrajan (eli < 1 - < 3 ng/m3). Muovituotetehtaissa kerätyistä VOC-näytteistä 16 %:sta löydettiin 2-etyyli-1-heksanolia, jonka pitoisuus vaihteli välillä 90 - 100 µg/m3. Virtsan 2-EHA-pitoisuudet olivat välillä <0,1 - 0,2 mmol/mol kreatiniinia. Tulosten perusteella siivoojat altistuvat TBEP:lle ja 2-butoksietanolille lattianvahauksen yhteydessä, muttaaltistuminen ei ilman pitoisuuksien ja biomonitoroinnin tulosten mukaan aiheutaterveyshaittaa ainakaan yhden mahdollisen metaboliitin 2-BAA:n kautta. Pois lukien raskaana olevat työntekijät, joille 2-butoksietanolia sisältävän vahanpoistotuotteen käsitteleminen aiheuttaa mahdollista terveyshaittaa. Käytetyillä biomonitorointimenetelmillä ei voitu osoittaa altistumista tapahtuneen mitatuilla TBEP:n ja TEHP:n pitoi-suustasoilla. Metaboliareittien varmistamisen jälkeen on mahdollista tutkia toimivampaa menetelmää altistumisen arviointiin biomonitoroinnin avulla. Työntekijöiden suojautuminen niin muovituotetehtaissa kuin siivoustyössäkin mitattujen yhdisteiden osalta oli pääosin riittävää. Ainoastaan raskaana olevien työntekijöiden, jotka siivoustyössään altistuvat 2-butoksietanolille, suojaukseen tulisi kiinnittää huomiota.
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Gold in the quartz-pebble conglomerates of the late Archean Witwatersrand Basin, South Africa, is often intimately associated with carbonaceous matter of organic/biogenic origin which occurs in the form of stratiform carbon seams and paragenetically late bitumen nodules. Both carbon forms are believed to be formed by solidification of migrating hydrocarbons. This paper presents bulk and molecular chemical and stable carbon isotope data for the carbonaceous matter, all of which are used to provide a clue to the source of the hydrocarbons. These data are compared with those from intra-basinal shales and overlying dolostone of the Transvaal Supergroup. The delta C-13 values of the extracts from the Witwatersrand carbonaceous material show small differences (up to 2.4 parts per thousand) compared to the associated insoluble organic matter. This suggests that the auriferous rocks were stained by mobile hydrocarbons produced by thermal and oxidative alteration of indigenous bitumens, a contribution from hydrocarbons derived from intra-basinal Witwatersrand shales cannot be excluded. Individual aliphatic hydrocarbons of the various carbonaceous materials were subjected to compound specific isotope analysis using on-line gas chromatography/combustion/stable isotope ratio mass spectrometry (GC/C/IRMS). The limited variability of the molecular parameters and uniform delta C-13 values of individual n-alkanes (-31.1 +/- 1.7 parts per thousand) and isoprenoids (-30.7 +/- 1.1 parts per thousand) in the Witwatersrand samples exclude the mixing of oils from different sources. Carbonaceous matter in the dolostones shows distinctly different bulk and molecular isotope characteristics and thus cannot have been the source of the hydrocarbons in the Witwatersrand deposits. All the various forms of Witwatersrand carbon appear indigenous to the Witwatersrand Basin, and the differences between them are explained by variable, in general probably short (centimeter- to meter-scale) hydrocarbon migration during diagenesis and subsequent hydrothermal infiltration. (C) 2001 Elsevier Science B.V. All rights reserved.
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Five selective serotonin reuptake inhibitors (SSRIs) have been introduced recently: citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline. Although no therapeutic window has been defined for SSRIs, in contrast to tricyclic antidepressants, analytical methods for therapeutic drug monitoring of SSRIs are useful in several instances. SSRIs differ widely in their chemical structure and in their metabolism. The fact that some of them have N-demethylated metabolites, which are also SSRIs, requires that methods be available which allow therapeutic drug monitoring of the parent compounds and of these active metabolites. most procedures are based on prepurification of the SSRIs by liquid-liquid extraction before they are submitted to separation by chromatographic procedures (high-performance liquid chromatography, gas chromatography, thin layer chromatography) and detection by various detectors (UV, fluorescence, electrochemical detector, nitrogen-phosphorus detector, mass spectrometry). This literature review shows that most methods allow quantitative determination of SSRIs in plasma, in the lower ng/ml range, and that they are, therefore, suitable for therapeutic drug monitoring purposes of this category of drugs.
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Asumisstrategia muodostaa kiinteän osan Imatran kaupungin kokonaisstrategiaa. Se laaditaan myös erillisenä strategia-asiakirjana. Tutkimuksen tavoitteena oli selvittää miten asumisstrategia toteutuu Imatran kaupungissa, mitkä tekijät tukevat asumisstrategian toteuttamista ja mitkä tekijät toimivat toteuttamisen esteinä sekämillainen asumisstrategiaprosessi on ja miten sitä voitaisiin kehittää. Tutkimus toteutettiin kvalitatiivisena tutkimuksena, jonka aineisto muodostuu asumisstrategiatyöryhmälle suunnatuista teemahaastatteluista ja käytössä olleista kaupungin strategia-asiakirjoista. Tutkimus toi esiin sen, kuinka vaikea ja monimuotoinen asumisstrategiaprosessi on sekä sen, kuinka monin eri tavoin asumisstrategiaa toteutetaan Imatran kaupungissa. Tutkimus toi esiin myös asumisstrategiaprosessiin liittyviä vahvuuksia ja heikkouksia sekä näiden, lähinnä hidasteiksi katsottavien tekijöiden poistamiseen käytettäviä kehittämiskeinoja. Tutkimuksen perusteella onnistunut strategian toteuttaminen edellyttää toimeenpanijoiden ymmärtävän strategian sisällön ja merkityksen omalle työlleen.
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Aim It is hypothesized that the ecological niches of polyploids should be both distinct and broader than those of diploids - characteristics that might have allowed the successful colonization of open habitats by polyploids during the Pleistocene glacial cycles. Here, we test these hypotheses by quantifying and comparing the ecological niches and niche breadths of a group of European primroses. Location Europe. Methods We gathered georeferenced data of four related species in Primula sect. Aleuritia at different ploidy levels (diploid, tetraploid, hexaploid and octoploid) and used seven bioclimatic variables to quantify niche overlap between species by applying a series of univariate and multivariate analyses combined with modelling techniques. We also employed permutation-based tests to evaluate niche similarity between the four species. Niche breadth for each species was evaluated both in the multivariate environmental space and in geographical space. Results The four species differed significantly from each other in mono-dimensional comparisons of climatological variables and occupied distinct habitats in the multi-dimensional environmental space. The majority of the permutation-based tests either indicated that the four species differed significantly in their habitat preferences and ecological niches or did not support significant niche similarity. Furthermore, our results revealed narrower niche breadths and geographical ranges in species of P. sect. Aleuritia at higher ploidy levels. Main conclusions The detected ecological differentiation between the four species of P. sect. Aleuritia at different ploidy levels is consistent with the hypothesis that polyploids occupy distinct ecological niches that differ from those of their diploid relative. Contrary to expectations, we find that polyploid species of P. sect. Aleuritia occupy narrower environmental and geographical spaces than their diploid relative. These results on the ecological niches of closely related polyploid and diploid species highlight factors that potentially contribute to the evolution and distribution of polyploid species.
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Résumé : Cette thèse de doctorat est le fruit d'un projet de recherche européen financé par le quatrième programme cadre de la Commission Européenne (DG XII, Standards, Measurement and Testing). Ce projet, dénommé SMT-CT98-2277, a été financé pour la partie suisse par l'Office Fédéral de l'Education et de la Science (OFES, Berne, Suisse). Le but de ce projet était de développer une méthode harmonisée et collaborativement testée pour le profilage des impuretés de l'amphétamine illicite par chromatographie capillaire en phase gazeuse. Le travail a été divisé en sept phases majeures qui concernaient la synthèse de l'amphétamine, l'identification d'impuretés, l'optimisation de la préparation de l'échantillon et du système chromatographique, la variabilité des résultats, l'investigation de méthodes mathématiques pour la classification et la comparaison de profils et finalement l'application de la méthode à des réels échantillons illicites. La méthode résultant de ce travail n'a pas seulement montré que les données étaient interchangeables entre laboratoires mais aussi qu'elle était supérieure en de nombreux points aux méthodes préalablement publiées dans la littérature scientifique. Abstract : This Ph.D. thesis was carried out in parallel to an European project funded by the fourth framework program of the European Commission (DG XII, Standards, Measurement and Testing). This project, named SMT-CT98-2277 was funded, for the Swiss part, by the Federal Office of Education and Science (OFES, Bern, Switzerland). The aim of the project was to develop a harmonised, collaboratively tested method for the impurity profiling of illicit amphetamine by capillary gas chromatography. The work was divided into seven main tasks which deal with the synthesis of amphetamine, identification of impurities, optimization of sample preparation and of the chromatographic system, variability of the results, investigation of numerical methods for the classification and comparison of profiles and finally application of the methodology to real illicit samples. The resulting method has not only shown to produce interchangeable data between different laboratories but was also found to be superior in many aspects to previously published methods.
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Due to the intense international competition, demanding, and sophisticated customers, and diverse transforming technological change, organizations need to renew their products and services by allocating resources on research and development (R&D). Managing R&D is complex, but vital for many organizations to survive in the dynamic, turbulent environment. Thus, the increased interest among decision-makers towards finding the right performance measures for R&D is understandable. The measures or evaluation methods of R&D performance can be utilized for multiple purposes; for strategic control, for justifying the existence of R&D, for providing information and improving activities, as well as for the purposes of motivating and benchmarking. The earlier research in the field of R&D performance analysis has generally focused on either the activities and considerable factors and dimensions - e.g. strategic perspectives, purposes of measurement, levels of analysis, types of R&D or phases of R&D process - prior to the selection of R&Dperformance measures, or on proposed principles or actual implementation of theselection or design processes of R&D performance measures or measurement systems. This study aims at integrating the consideration of essential factors anddimensions of R&D performance analysis to developed selection processes of R&D measures, which have been applied in real-world organizations. The earlier models for corporate performance measurement that can be found in the literature, are to some extent adaptable also to the development of measurement systemsand selecting the measures in R&D activities. However, it is necessary to emphasize the special aspects related to the measurement of R&D performance in a way that make the development of new approaches for especially R&D performance measure selection necessary: First, the special characteristics of R&D - such as the long time lag between the inputs and outcomes, as well as the overall complexity and difficult coordination of activities - influence the R&D performance analysis problems, such as the need for more systematic, objective, balanced and multi-dimensional approaches for R&D measure selection, as well as the incompatibility of R&D measurement systems to other corporate measurement systems and vice versa. Secondly, the above-mentioned characteristics and challenges bring forth the significance of the influencing factors and dimensions that need to be recognized in order to derive the selection criteria for measures and choose the right R&D metrics, which is the most crucial step in the measurement system development process. The main purpose of this study is to support the management and control of the research and development activities of organizations by increasing the understanding of R&D performance analysis, clarifying the main factors related to the selection of R&D measures and by providing novel types of approaches and methods for systematizing the whole strategy- and business-based selection and development process of R&D indicators.The final aim of the research is to support the management in their decision making of R&D with suitable, systematically chosen measures or evaluation methods of R&D performance. Thus, the emphasis in most sub-areas of the present research has been on the promotion of the selection and development process of R&D indicators with the help of the different tools and decision support systems, i.e. the research has normative features through providing guidelines by novel types of approaches. The gathering of data and conducting case studies in metal and electronic industry companies, in the information and communications technology (ICT) sector, and in non-profit organizations helped us to formulate a comprehensive picture of the main challenges of R&D performance analysis in different organizations, which is essential, as recognition of the most importantproblem areas is a very crucial element in the constructive research approach utilized in this study. Multiple practical benefits regarding the defined problemareas could be found in the various constructed approaches presented in this dissertation: 1) the selection of R&D measures became more systematic when compared to the empirical analysis, as it was common that there were no systematic approaches utilized in the studied organizations earlier; 2) the evaluation methods or measures of R&D chosen with the help of the developed approaches can be more directly utilized in the decision-making, because of the thorough consideration of the purpose of measurement, as well as other dimensions of measurement; 3) more balance to the set of R&D measures was desired and gained throughthe holistic approaches to the selection processes; and 4) more objectivity wasgained through organizing the selection processes, as the earlier systems were considered subjective in many organizations. Scientifically, this dissertation aims to make a contribution to the present body of knowledge of R&D performance analysis by facilitating dealing with the versatility and challenges of R&D performance analysis, as well as the factors and dimensions influencing the selection of R&D performance measures, and by integrating these aspects to the developed novel types of approaches, methods and tools in the selection processes of R&D measures, applied in real-world organizations. In the whole research, facilitation of dealing with the versatility and challenges in R&D performance analysis, as well as the factors and dimensions influencing the R&D performance measure selection are strongly integrated with the constructed approaches. Thus, the research meets the above-mentioned purposes and objectives of the dissertation from the scientific as well as from the practical point of view.
Resumo:
The objectives of this study were to evaluate the residues of the insecticide carbosulfan and its carbofuran metabolites and 3-hydroxy-carbofuran in orange compartments (whole fruit, bagasse and juice) and comparison between the residual levels found in fruits with the maximum residue level and the safety interval established by the Brazilian legislation. Two field experiments were carried out, both with the following treatments: a-check; b-one application of 10 g of carbosulfan . 100 L-1 of water; c-one application with twice the rate applied in treatment b; d-four applications with the same rate applied in treatment b. Samples were taken at (-1), zero, 1, 3, 7, 14, 21 and 28 days after the last or unique application. The quantitative determinations were done by gas chromatography technique, using a nitrogen-phosphorus detector. The carbosulfan metabolism to its carbofuran metabolite was rapid (3 days), being both analytes concentrated in the bagasse (peel + flavedo + albedo). However, the metabolism of carbofuran to 3-hydroxy-carbofuran was of low intensity or this metabolite was quickly dissipated. Carbosulfan residues and its metabolites did not penetrate into the fruit, thus not contaminating the juice. The use of the pesticide was adequate, with respect to fruit consumption, in relation to the Brazilian legislation.