964 resultados para 250406 Immunological and Bioassay Methods


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Background: Little is known on the relative importance of growth at different periods between birth and adolescence on blood pressure (BP). Objective: To assess the association between birth weight, change in body weight (growth) and BP across the entire span of childhood and adolescence. Methods: School-based surveys were conducted annually between 1998 and 2006 among all children in four school grades (kindergarten, 4th, 7th, and 10th year of compulsory school) in the Seychelles, Indian Ocean. Height and weight and BP were measured. Three cohorts of children examined twice were analyzed: 1606 children surveyed at age 5.5 and 9.1, 2557 at age 9.2 and 12.5, and 2065 at age 12.5 and 15.5, respectively. Weights at birth and at one year were extracted from medical files. Weights were expressed as Z-scores and growth was defined as a change in weight Z-scores (corresponding to weight centile crossing). The association between BP (at age 5.5, 9.2, 12.5, and 15.5) and weight at different times was assessed by linear regression. Using results of regression models of BP on all successive weights, life course plots were drawn by plotting regression coefficients against age at which weight was measured. The figure shows a life course plot of systolic BP in boys aged 15.5. Results: Without adjustment for current weight (at the time of BP measurement), birth weight was not associated with current BP, irrespective of age, excepted for girls at age 15.5 for whom a modest positive association was found. When adjusted for current weight, birth weight was negatively and modestly associated with current BP. BP was strongly associated with current weight, irrespective of age. Life course plots showed that BP was strongly associated with growth during the few preceding years but not with growth during earlier years, except for growth during the first year of life which tended to be associated with systolic BP. Conclusions: Our findings suggest that BP during childhood and adolescence is mainly determined by current body weight and recent growth.

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ABSTRACT: BACKGROUND: Fractures associated with bone fragility in older adults signal the potential for secondary fracture. Fragility fractures often precipitate further decline in health and loss of mobility, with high associated costs for patients, families, society and the healthcare system. Promptly initiating a coordinated, comprehensive pharmacological bone health and falls prevention program post-fracture may improve osteoporosis treatment compliance; and reduce rates of falls and secondary fractures, and associated morbidity, mortality and costs.Methods/design: This pragmatic, controlled trial at 11 hospital sites in eight regions in Quebec, Canada, will recruit community-dwelling patients over age 50 who have sustained a fragility fracture to an intervention coordinated program or to standard care, according to the site. Site study coordinators will identify and recruit 1,596 participants for each study arm. Coordinators at intervention sites will facilitate continuity of care for bone health, and arrange fall prevention programs including physical exercise. The intervention teams include medical bone specialists, primary care physicians, pharmacists, nurses, rehabilitation clinicians, and community program organizers.The primary outcome of this study is the incidence of secondary fragility fractures within an 18-month follow-up period. Secondary outcomes include initiation and compliance with bone health medication; time to first fall and number of clinically significant falls; fall-related hospitalization and mortality; physical activity; quality of life; fragility fracture-related costs; admission to a long term care facility; participants' perceptions of care integration, expectations and satisfaction with the program; and participants' compliance with the fall prevention program. Finally, professionals at intervention sites will participate in focus groups to identify barriers and facilitating factors for the integrated fragility fracture prevention program.This integrated program will facilitate knowledge translation and dissemination via the following: involvement of various collaborators during the development and set-up of the integrated program; distribution of pamphlets about osteoporosis and fall prevention strategies to primary care physicians in the intervention group and patients in the control group; participation in evaluation activities; and eventual dissemination of study results.Study/trial registration: Clinical Trial.Gov NCT01745068Study ID number: CIHR grant # 267395.

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The thesis addresses the issue of parenthood and gender equality in Switzerland through the emergence of parental leave policies. This is an original and relevant research topic, as Switzerland is one of the few industrialized countries that have not yet implemented a parental or paternity leave. I first describe the emergence of parental leave policies in the last ten to fifteen years in the political, media, and labor-market spheres. Secondly, adopting a gender and discursive theoretical approach, I analyze whether and to what extent this emergence challenged gendered representations and practices of parenthood. The multilevel and mixed-methods research design implies analyzing various data sets such as parliamentary interventions (N=23J and newspaper articles (N=579) on parental leave policies. A case study of a public administration which implemented a one-month paid paternity leave draws on register data of leave recipients (N=95) and in-depth interviews with fathers and managers (n=30). Results show that parental leave policies, especially in recent years, have been increasingly problematized in the three social spheres considered, as a result of political and institutional events. While there is a struggle over the definition of the legitimate leave type to implement [parental or paternity leave) in the political sphere, paternity leave has precedence in the media and labor-market spheres. Overall, this emergence contributes to making fatherhood visible in the public sphere, challenging albeit in a limited way gendered representations and practices of parenthood. Along with representations of involved fatherhood and change in gender relations, different roles and responsibilities are attributed to mothers and fathers, the latter being often defined as secondary, temporary and optional parents. Finally, I identify a common trend, namely the increasing importance of the economic aspects of parental leave policies with the consequence of sidelining their gender-equality potential. The dissertation contributes to the literature which analyzes the interconnections between the macro-, the meso- and the micro-levels of society in the constitution of gender relations and parenthood. It also provides useful tools for the analysis of the politics of parental leave policies in Switzerland and their effects for gender equality. - Cette thèse traite de la parentalité et de l'égalité de genre en Suisse à travers l'émergence des congés parentaux. Ce sujet de recherche est original et pertinent puisque la Suisse est à ce jour un des seuls pays industrialisés à ne pas avoir adopté de droit au congé parental ou paternité. Cette recherche décrit l'émergence des congés parentaux au cours des 10 à 15 dernières années dans les sphères politique, médiatique et du marché de l'emploi en Suisse. En combinant perspective de genre et analyse de discours, elle examine dans quelle mesure cette émergence remet en question les représentations et pratiques genrées de parentalité. Des méthodes de recherche mixtes sont employées pour analyser des interventions parlementaires (N=23) et des articles de presse (N=579) sur les congés parentaux. L'étude de cas d une entreprise publique qui a adopté un congé paternité payé d'un mois s'appuie sur des données de registre (N=95) et des entretiens semi-structurés avec des pères et des cadres (n=30). Les résultats indiquent que dans les trois sphères considérées, les congés parentaux ont reçu une attention croissante au cours de ces dernières années, en lien avec des événements politiques et institutionnels. Alors que dans la sphère politique il n'y a pas de consensus quant au type de congé considéré comme légitime (congé parental ou paternité), dans les sphères médiatique et du marché de l'emploi le congé paternité semble l'emporter. Dans l'ensemble, l'émergence des congés parentaux contribue à rendre la paternité plus visible dans l'espace public, remettant en question-bien que d'une manière limitée-les représentations genrées de la parentalité. En effet, d'une part l'image de pères impliqués et de rapports de genre plus égalitaires au sein de la famille est diffusée. D'autre part, mères et pères continuent à être associés à des rôles différents, les pères étant définis comme des parents secondaires et temporaires. Finalement, l'analyse révèle une tendance générale, soit l'importance croissante accordée aux aspects économiques des congés parentaux, avec pour conséquence la mise à l'écart de leur potentiel pour l'égalité de genre. Cette thèse contribue à la recherche sur les liens entre les niveaux macro- meso- et microsociaux dans la constitution des rapports de genre et de la parentalité. Elle propose également des outils pour analyser les politiques de congés parentaux en Suisse et leurs implications pour l'égalité de genre.

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Professional cleaning is a basic service occupation with a wide variety of tasks carried out in all kind of different sectors and workplaces by a large workforce. One important risk for cleaning workers is the exposure to chemical substances that are present in cleaning products.Monoethanolamine was found to be often present in cleaning products such as general purpose cleaners, bathroom cleaners, floor cleaners and kitchen cleaners. Monoethanolamine can injure the skin, and exposure to monoethanolamine was associated to asthma even when the air concentrations were low. It is a strong irritant and known to be involved in sensitizing mechanisms. It is very likely that the use of cleaning products containing monoethanolamine gives rise to respiratory and dermal exposures. Therefore there is a need to further investigate the exposures to monoethanolamine for both, respiratory and dermal exposure.The determination of monoethanolamine has traditionally been difficult and analytical methods available are little adapted for occupational exposure assessments. For monoethanolamine air concentrations, a sampling and analytical method was already available and could be used. However, a method to analyses samples for skin exposure assessments as well as samples of skin permeation experiments was missing. Therefore one main objective of this master thesis was to search an already developed and described analytical method for the measurement of monoethanolamine in water solutions, and to set it up in the laboratory. Monoethanolamine was analyzed after a derivatisation reaction with o-pthtaldialdehyde. The derivated fluorescing monoethanolamine was then separated with high performance liquid chromatography and detection took place with a fluorescent detector. The method was found to be suitable for qualitative and quantitative analysis of monoethanolamine. An exposure assessment was conducted in the cleaning sector to measure the respiratory and dermal exposures to monoethanolamine during floor cleaning. Stationary air samples (n=36) were collected in 8 companies and samples for dermal exposures (n=12) were collected in two companies. Air concentrations (Mean = 0.18 mg/m3, Standard Deviation = 0.23 mg/m3, geometric Mean = 0.09 mg/m3, Geometric Standard Deviation = 3.50) detected were mostly below 1/10 of the Swiss 8h time weighted average occupational exposure limit. Factors that influenced the measured monoethanolamine air concentrations were room size, ventilation system and the concentration of monoethanolamine in the cleaning product and amount of monoethanolamine used. Measured skin exposures ranged from 0.6 to 128.4 mg/sample. Some cleaning workers that participated in the skin exposure assessment did not use gloves and had direct contact with the solutions containing the cleaning product and monoethanolamine. During the entire sampling campaign, cleaning workers mostly did not use gloves. Cleaning workers are at risk to be regularly exposed to low air concentrations of monoethanolamine. This exposure may be problematic if a worker suffers from allergic reactions (e.g. Asthma). In that case a substitution of the cleaning product may be a good prevention measure as several different cleaning products are available for similar cleaning tasks. Currently there are no occupational exposure limits to compare the skin exposures that were found. To prevent skin exposures, adaptations of the cleaning techniques and the use of gloves should be considered. The simultaneous skin and airborne exposures might accelerate adverse health effects. Overall the risks caused by exposures to monoethanolamine are considered as low to moderate when the cleaning products are used correctly. Whenever possible, skin exposures should be avoided. Further research should consider especially the dermal exposure routes, as very high exposures might occur by skin contact with cleaning products. Dermatitis but also sensitization might be caused by skin exposures. In addition, new biomedical insights are needed to better understand the risks of the dermal exposure. Therefore skin permeability experiments should be considered.

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We present the most comprehensive comparison to date of the predictive benefit of genetics in addition to currently used clinical variables, using genotype data for 33 single-nucleotide polymorphisms (SNPs) in 1,547 Caucasian men from the placebo arm of the REduction by DUtasteride of prostate Cancer Events (REDUCE®) trial. Moreover, we conducted a detailed comparison of three techniques for incorporating genetics into clinical risk prediction. The first method was a standard logistic regression model, which included separate terms for the clinical covariates and for each of the genetic markers. This approach ignores a substantial amount of external information concerning effect sizes for these Genome Wide Association Study (GWAS)-replicated SNPs. The second and third methods investigated two possible approaches to incorporating meta-analysed external SNP effect estimates - one via a weighted PCa 'risk' score based solely on the meta analysis estimates, and the other incorporating both the current and prior data via informative priors in a Bayesian logistic regression model. All methods demonstrated a slight improvement in predictive performance upon incorporation of genetics. The two methods that incorporated external information showed the greatest receiver-operating-characteristic AUCs increase from 0.61 to 0.64. The value of our methods comparison is likely to lie in observations of performance similarities, rather than difference, between three approaches of very different resource requirements. The two methods that included external information performed best, but only marginally despite substantial differences in complexity.

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We have constructed a forward modelling code in Matlab, capable of handling several commonly used electrical and electromagnetic methods in a 1D environment. We review the implemented electromagnetic field equations for grounded wires, frequency and transient soundings and present new solutions in the case of a non-magnetic first layer. The CR1Dmod code evaluates the Hankel transforms occurring in the field equations using either the Fast Hankel Transform based on digital filter theory, or a numerical integration scheme applied between the zeros of the Bessel function. A graphical user interface allows easy construction of 1D models and control of the parameters. Modelling results are in agreement with other authors, but the time of computation is less efficient than other available codes. Nevertheless, the CR1Dmod routine handles complex resistivities and offers solutions based on the full EM-equations as well as the quasi-static approximation. Thus, modelling of effects based on changes in the magnetic permeability and the permittivity is also possible.

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The spatial resolution visualized with hydrological models and the conceptualized images of subsurface hydrological processes often exceed resolution of the data collected with classical instrumentation at the field scale. In recent years it was possible to increasingly diminish the inherent gap to information from point like field data through the application of hydrogeophysical methods at field-scale. With regards to all common geophysical exploration techniques, electric and electromagnetic methods have arguably to greatest sensitivity to hydrologically relevant parameters. Of particular interest in this context are induced polarisation (IP) measurements, which essentially constrain the capacity of a probed subsurface region to store an electrical charge. In the absence of metallic conductors the IP- response is largely driven by current conduction along the grain surfaces. This offers the perspective to link such measurements to the characteristics of the solid-fluid-interface and thus, at least in unconsolidated sediments, should allow for first-order estimates of the permeability structure.¦While the IP-effect is well explored through laboratory experiments and in part verified through field data for clay-rich environments, the applicability of IP-based characterizations to clay-poor aquifers is not clear. For example, polarization mechanisms like membrane polarization are not applicable in the rather wide pore-systems of clay free sands, and the direct transposition of Schwarz' theory relating polarization of spheres to the relaxation mechanism of polarized cells to complex natural sediments yields ambiguous results.¦In order to improve our understanding of the structural origins of IP-signals in such environments as well as their correlation with pertinent hydrological parameters, various laboratory measurements have been conducted. We consider saturated quartz samples with a grain size spectrum varying from fine sand to fine gravel, that is grain diameters between 0,09 and 5,6 mm, as well as corresponding pertinent mixtures which can be regarded as proxies for widespread alluvial deposits. The pore space characteristics are altered by changing (i) the grain size spectra, (ii) the degree of compaction, and (iii) the level of sorting. We then examined how these changes affect the SIP response, the hydraulic conductivity, and the specific surface area of the considered samples, while keeping any electrochemical variability during the measurements as small as possible. The results do not follow simple assumptions on relationships to single parameters such as grain size. It was found that the complexity of natural occurring media is not yet sufficiently represented when modelling IP. At the same time simple correlation to permeability was found to be strong and consistent. Hence, adaptations with the aim of better representing the geo-structure of natural porous media were applied to the simplified model space used in Schwarz' IP-effect-theory. The resulting semi- empiric relationship was found to more accurately predict the IP-effect and its relation to the parameters grain size and permeability. If combined with recent findings about the effect of pore fluid electrochemistry together with advanced complex resistivity tomography, these results will allow us to picture diverse aspects of the subsurface with relative certainty. Within the framework of single measurement campaigns, hydrologiste can than collect data with information about the geo-structure and geo-chemistry of the subsurface. However, additional research efforts will be necessary to further improve the understanding of the physical origins of IP-effect and minimize the potential for false interpretations.¦-¦Dans l'étude des processus et caractéristiques hydrologiques des subsurfaces, la résolution spatiale donnée par les modèles hydrologiques dépasse souvent la résolution des données du terrain récoltées avec des méthodes classiques d'hydrologie. Récemment il est possible de réduire de plus en plus cet divergence spatiale entre modèles numériques et données du terrain par l'utilisation de méthodes géophysiques, notamment celles géoélectriques. Parmi les méthodes électriques, la polarisation provoquée (PP) permet de représenter la capacité des roches poreuses et des sols à stocker une charge électrique. En l'absence des métaux dans le sous-sol, cet effet est largement influencé par des caractéristiques de surface des matériaux. En conséquence les mesures PP offrent une information des interfaces entre solides et fluides dans les matériaux poreux que nous pouvons lier à la perméabilité également dirigée par ces mêmes paramètres. L'effet de la polarisation provoquée à été étudié dans différentes études de laboratoire, ainsi que sur le terrain. A cause d'une faible capacité de polarisation des matériaux sableux, comparé aux argiles, leur caractérisation par l'effet-PP reste difficile a interpréter d'une manière cohérente pour les environnements hétérogènes.¦Pour améliorer les connaissances sur l'importance de la structure du sous-sol sableux envers l'effet PP et des paramètres hydrologiques, nous avons fait des mesures de laboratoire variées. En détail, nous avons considéré des échantillons sableux de quartz avec des distributions de taille de grain entre sables fins et graviers fins, en diamètre cela fait entre 0,09 et 5,6 mm. Les caractéristiques de l'espace poreux sont changées en modifiant (i) la distribution de taille des grains, (ii) le degré de compaction, et (iii) le niveau d'hétérogénéité dans la distribution de taille de grains. En suite nous étudions comment ces changements influencent l'effet-PP, la perméabilité et la surface spécifique des échantillons. Les paramètres électrochimiques sont gardés à un minimum pendant les mesures. Les résultats ne montrent pas de relation simple entre les paramètres pétro-physiques comme par exemples la taille des grains. La complexité des media naturels n'est pas encore suffisamment représenté par les modèles des processus PP. Néanmoins, la simple corrélation entre effet PP et perméabilité est fort et consistant. En conséquence la théorie de Schwarz sur l'effet-PP a été adapté de manière semi-empirique pour mieux pouvoir estimer la relation entre les résultats de l'effet-PP et les paramètres taille de graines et perméabilité. Nos résultats concernant l'influence de la texture des matériaux et celles de l'effet de l'électrochimie des fluides dans les pores, permettront de visualiser des divers aspects du sous-sol. Avec des telles mesures géo-électriques, les hydrologues peuvent collectionner des données contenant des informations sur la structure et la chimie des fluides des sous-sols. Néanmoins, plus de recherches sur les origines physiques de l'effet-PP sont nécessaires afin de minimiser le risque potentiel d'une mauvaise interprétation des données.

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Initiation of antiretroviral therapy during the earliest stages of HIV-1 infection may limit the seeding of a long-lasting viral reservoir, but long-term effects of early antiretroviral treatment initiation remain unknown. Here, we analyzed immunological and virological characteristics of nine patients who started antiretroviral therapy at primary HIV-1 infection and remained on suppressive treatment for >10 years; patients with similar treatment duration but initiation of suppressive therapy during chronic HIV-1 infection served as controls. We observed that independently of the timing of treatment initiation, HIV-1 DNA in CD4 T cells decayed primarily during the initial 3 to 4 years of treatment. However, in patients who started antiretroviral therapy in early infection, this decay occurred faster and was more pronounced, leading to substantially lower levels of cell-associated HIV-1 DNA after long-term treatment. Despite this smaller size, the viral CD4 T cell reservoir in persons with early treatment initiation consisted more dominantly of the long-lasting central-memory and T memory stem cells. HIV-1-specific T cell responses remained continuously detectable during antiretroviral therapy, independently of the timing of treatment initiation. Together, these data suggest that early HIV-1 treatment initiation, even when continued for >10 years, is unlikely to lead to viral eradication, but the presence of low viral reservoirs and durable HIV-1 T cell responses may make such patients good candidates for future interventional studies aiming at HIV-1 eradication and cure. IMPORTANCE: Antiretroviral therapy can effectively suppress HIV-1 replication to undetectable levels; however, HIV-1 can persist despite treatment, and viral replication rapidly rebounds when treatment is discontinued. This is mainly due to the presence of latently infected CD4 T cells, which are not susceptible to antiretroviral drugs. Starting treatment in the earliest stages of HIV-1 infection can limit the number of these latently infected cells, raising the possibility that these viral reservoirs are naturally eliminated if suppressive antiretroviral treatment is continued for extremely long periods of time. Here, we analyzed nine patients who started on antiretroviral therapy within the earliest weeks of the disease and continued treatment for more than 10 years. Our data show that early treatment accelerated the decay of infected CD4 T cells and led to very low residual levels of detectable HIV-1 after long-term therapy, levels that were otherwise detectable in patients who are able to maintain a spontaneous, drug-free control of HIV-1 replication. Thus, long-term antiretroviral treatment started during early infection cannot eliminate HIV-1, but the reduced reservoirs of HIV-1 infected cells in such patients may increase their chances to respond to clinical interventions aiming at inducing a drug-free remission of HIV-1 infection.

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Biocides are widely used for domestic hygiene, agricultural and industrial applications. Their widespread use has resulted in their introduction into the environment and raised concerns about potential deleterious effects on aquatic ecosystems. In this study, the toxicity of the biocides triclosan, penconazole and metalaxyl were evaluated with the freshwater bacterium Caulobacter crescentus and with a freshwater microbial community using a combination of single- and double-stain flow cytometric assays. Growth of C.  crescentus and the freshwater community were repressed by triclosan but not by penconazole or metalaxyl at concentrations up to 250 μM. The repressive effect of triclosan was dependent on culture conditions. Caulobacter crescentus was more sensitive to triclosan when grown with high glucose at high cell density than when grown directly in sterilized lake water at low cell density. This suggests that the use of conventional growth conditions may overestimate biocide toxicity. Additional experiments showed that the freshwater community was more sensitive to triclosan than C.  crescentus, with 10 nM of triclosan being sufficient to repress growth and change the phylogenetic composition of the community. These results demonstrate that isolate-based assays may underestimate biocide toxicity and highlight the importance of assessing toxicity directly on natural microbial communities. Because 10 nM of triclosan is within the range of concentrations observed in freshwater systems, these results also raise concerns about the risk of introducing triclosan into the environment.

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BACKGROUND: Sunitinib (VEGFR/PDGFR inhibitor) and everolimus (mTOR inhibitor) are both approved for advanced renal cell carcinoma (RCC) as first-line and second-line therapy, respectively. In the clinics, sunitinib treatment is limited by the emergence of acquired resistance, leading to a switch to second-line treatment at progression, often based on everolimus. No data have been yet generated on programmed alternating sequential strategies combining alternative use of sunitinib and everolimus before progression. Such strategy is expected to delay the emergence of acquired resistance and improve tumour control. The aim of our study was to assess the changes in tumours induced by three different sequences administration of sunitinib and everolimus. METHODS: In human Caki-1 RCC xenograft model, sunitinib was alternated with everolimus every week, every 2 weeks, or every 3 weeks. Effects on necrosis, hypoxia, angiogenesis, and EMT status were assessed by immunohisochemistry and immunofluorescence. RESULTS: Sunitinib and everolimus programmed sequential regimens before progression yielded longer median time to tumour progression than sunitinib and everolimus monotherapies. In each group of treatment, tumour growth control was associated with inhibition of mTOR pathway and changes from a mesenchymal towards an epithelial phenotype, with a decrease in vimentin and an increase in E-cadherin expression. The sequential combinations of these two agents in a RCC mouse clinical trial induced antiangiogenic effects, leading to tumour necrosis. CONCLUSIONS: In summary, our study showed that alternate sequence of sunitinib and everolimus mitigated the development of mesenchymal phenotype compared with sunitinib as single agent.

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Työn tavoite onharmonisoida yhtenäiset rakenteet UPM:n paperi- ja sellutehtaiden merkittävilleympäristönäkökohdille sekä niiden ympäristöriskienhallintajärjestelmille. Näin saavutetaan yhteneväiset tavoitteet ja analysointikeinot yrityksen yksiköille. Harmonisointiprosessi on osa koko yrityksen ympäristöhallintajärjestelmän kehittämistä. Ja konsernin EMS -prosessi puolestaan konvergoi konsernin integroidun johtamisjärjestelmän kehitystä. Lisäksi työn tapaustutkimuksessa selvitettiin riskienhallintajärjestelmien integroitumispotentiaalia. Sen avulla saavutettaisiin paremmin suuren yrityksen synergia-etuja ja vuorovaikutteisuutta toimijoiden kesken, sekä parannettaisiin riskienhallintajärjestelmän mukautuvuutta ja käytettävyyttä. Työssä käsitellään kolmea esimerkkiä, joiden pohjalta tehdään esitys harmonisoiduille merkittäville ympäristönäkökohdille sekä riskienhallintajärjestelmien parametreille. Tutkimusongelmaa lähestytään haastattelujen, kirjallisuuden, yrityksen PWC:llä teettämän selvityksen sekä omien päätelmien avulla. Lisäksi työssä esitetään ympäristöhallintajärjestelmän tehokkuuden todentaminen ympäristösuorituskyvyn muuttujiin suhteutettuna. Pohjana jatkuvan kehityksen päämäärälle on organisaatio-oppiminen, niin yksittäisen työntekijän, tiimien kuin eri yksiköiden kesken. Se antaa sysäyksen aineettoman omaisuuden, kuten ympäristö-osaamisen, hyödyntämiseen parhaalla mahdollisella tavalla. Tärkeimpinä lopputuloksina työssä ovat ehdotukset harmonisoiduille merkittäville ympäristönäkökohdille sekä ympäristöriskienhallintajärjestelmän määritetyille komponenteille. Niitä ovat määritelmät ja skaalat riskien todennäköisyydelle, seurauksille sekä riskiluokille. Työn viimeisenä osana luodaan pohja tapaustutkimuksen avulla Rauman tehtaan jätevedenpuhdistamon kahden erilaisen riskienhallintajärjestelmän integroitumiselle.

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In this work the adsorption mechanisms of atomic and molecular oxygen on Cu(100) surface are studied using ab initio simulation methods. Through the atomistic scale under-standing of the elementary oxidation processes we can further understand the large-scale oxidation. Copper is a material widely used in industry which makes it an interesting subject, and also understanding the oxidation of copper helps us understand the oxidation mechanism of other metals. First we have a look on some theory on surface alloys in general and behaviour of Ag on Cu(100) surface. After that the physical background there is behind the methods of density functional calculations are discussed, and some methods, namely potential energy surfaces and molecular dynamics, are introduced. Then there is a brief look on the numerical details used in the calculations, and after that, the results of the simulations are exhibited.

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This master's thesis coversthe concepts of knowledge discovery, data mining and technology forecasting methods in telecommunications. It covers the various aspects of knowledge discoveryin data bases and discusses in detail the methods of data mining and technologyforecasting methods that are used in telecommunications. Main concern in the overall process of this thesis is to emphasize the methods that are being used in technology forecasting for telecommunications and data mining. It tries to answer to some extent to the question of do forecasts create a future? It also describes few difficulties that arise in technology forecasting. This thesis was done as part of my master's studies in Lappeenranta University of Technology.

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Yksi keskeisimmistä tehtävistä matemaattisten mallien tilastollisessa analyysissä on mallien tuntemattomien parametrien estimointi. Tässä diplomityössä ollaan kiinnostuneita tuntemattomien parametrien jakaumista ja niiden muodostamiseen sopivista numeerisista menetelmistä, etenkin tapauksissa, joissa malli on epälineaarinen parametrien suhteen. Erilaisten numeeristen menetelmien osalta pääpaino on Markovin ketju Monte Carlo -menetelmissä (MCMC). Nämä laskentaintensiiviset menetelmät ovat viime aikoina kasvattaneet suosiotaan lähinnä kasvaneen laskentatehon vuoksi. Sekä Markovin ketjujen että Monte Carlo -simuloinnin teoriaa on esitelty työssä siinä määrin, että menetelmien toimivuus saadaan perusteltua. Viime aikoina kehitetyistä menetelmistä tarkastellaan etenkin adaptiivisia MCMC menetelmiä. Työn lähestymistapa on käytännönläheinen ja erilaisia MCMC -menetelmien toteutukseen liittyviä asioita korostetaan. Työn empiirisessä osuudessa tarkastellaan viiden esimerkkimallin tuntemattomien parametrien jakaumaa käyttäen hyväksi teoriaosassa esitettyjä menetelmiä. Mallit kuvaavat kemiallisia reaktioita ja kuvataan tavallisina differentiaaliyhtälöryhminä. Mallit on kerätty kemisteiltä Lappeenrannan teknillisestä yliopistosta ja Åbo Akademista, Turusta.

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QUESTIONS UNDER STUDY: The field of heart transplantation has seen substantial progress in the last 40 years. The breakthroughs in long-term survival were followed by a period of stagnation in the last decade. This review summarises current recommendations for the identification of candidates for heart transplantation and their immunological and non-immunological postoperative follow-up. RESULTS: The progress made in the treatment of patients with advanced heart failure has considerably changed the profile of candidates for heart transplantation. Patients are older, and the load of co-morbidities is more important requiring careful evaluation for candidacy. Long-standing research in the field of immunosuppression made available various drugs, which decrease the risk of acute allograft rejection and prolong survival after heart transplantation. Powerful new molecules are entering early phase clinical studies, suggesting further improvement in the near future. As a consequence, treatment of non-immunological co-morbidity after heart transplantation will gain in importance, however, the base of evidence guiding current recommendations is poor. CONCLUSIONS: The substantial progress in heart failure treatment and immunosuppression after heart transplantation has changed the profile of heart transplant recipients. The arrival of new molecules will provide additional alternatives for immunosuppressive treatment while studies have to address non-immunological treatment in order to improve long-term survival after heart transplantation.