960 resultados para Parametric and semiparametric methods


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Mixture materials, mix design, and pavement construction are not isolated steps in the concrete paving process. Each affects the other in ways that determine overall pavement quality and long-term performance. However, equipment and procedures commonly used to test concrete materials and concrete pavements have not changed in decades, leaving gaps in our ability to understand and control the factors that determine concrete durability. The concrete paving community needs tests that will adequately characterize the materials, predict interactions, and monitor the properties of the concrete. The overall objectives of this study are (1) to evaluate conventional and new methods for testing concrete and concrete materials to prevent material and construction problems that could lead to premature concrete pavement distress and (2) to examine and refine a suite of tests that can accurately evaluate concrete pavement properties. The project included three phases. In Phase I, the research team contacted each of 16 participating states to gather information about concrete and concrete material tests. A preliminary suite of tests to ensure long-term pavement performance was developed. The tests were selected to provide useful and easy-to-interpret results that can be performed reasonably and routinely in terms of time, expertise, training, and cost. The tests examine concrete pavement properties in five focal areas critical to the long life and durability of concrete pavements: (1) workability, (2) strength development, (3) air system, (4) permeability, and (5) shrinkage. The tests were relevant at three stages in the concrete paving process: mix design, preconstruction verification, and construction quality control. In Phase II, the research team conducted field testing in each participating state to evaluate the preliminary suite of tests and demonstrate the testing technologies and procedures using local materials. A Mobile Concrete Research Lab was designed and equipped to facilitate the demonstrations. This report documents the results of the 16 state projects. Phase III refined and finalized lab and field tests based on state project test data. The results of the overall project are detailed herein. The final suite of tests is detailed in the accompanying testing guide.

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OBJECTIVE: Genetic studies might provide new insights into the biological mechanisms underlying lipid metabolism and risk of CAD. We therefore conducted a genome-wide association study to identify novel genetic determinants of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. METHODS AND RESULTS: We combined genome-wide association data from 8 studies, comprising up to 17 723 participants with information on circulating lipid concentrations. We did independent replication studies in up to 37 774 participants from 8 populations and also in a population of Indian Asian descent. We also assessed the association between single-nucleotide polymorphisms (SNPs) at lipid loci and risk of CAD in up to 9 633 cases and 38 684 controls. We identified 4 novel genetic loci that showed reproducible associations with lipids (probability values, 1.6×10(-8) to 3.1×10(-10)). These include a potentially functional SNP in the SLC39A8 gene for HDL-C, an SNP near the MYLIP/GMPR and PPP1R3B genes for LDL-C, and at the AFF1 gene for triglycerides. SNPs showing strong statistical association with 1 or more lipid traits at the CELSR2, APOB, APOE-C1-C4-C2 cluster, LPL, ZNF259-APOA5-A4-C3-A1 cluster and TRIB1 loci were also associated with CAD risk (probability values, 1.1×10(-3) to 1.2×10(-9)). CONCLUSIONS: We have identified 4 novel loci associated with circulating lipids. We also show that in addition to those that are largely associated with LDL-C, genetic loci mainly associated with circulating triglycerides and HDL-C are also associated with risk of CAD. These findings potentially provide new insights into the biological mechanisms underlying lipid metabolism and CAD risk.

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Background: Visual analog scales (VAS) are used to assess readiness to changeconstructs, which are often considered critical for change.Objective: We studied whether 3 constructs -readiness to change, importance of changing and confidence inability to change- predict risk status 6 months later in 20 year-old men with either orboth of two behaviors: risky drinking and smoking. Methods: 577 participants in abrief intervention randomized trial were assessed at baseline and 6 months later onalcohol and tobacco consumption and with three 1-10 VAS (readiness, importance,confidence) for each behavior. For each behavior, we used one regression model foreach constructs. Models controlled for receipt of a brief intervention and used thelowest level (1-4) in each construct as the reference group (vs medium (5-7) and high(8-10) levels).Results: Among the 475 risky drinkers, mean (SD) readiness, importance and confidence to change drinking were 4.0 (3.1), 2.8 (2.2) and 7.2 (3.0).Readiness was not associated with being alcohol-risk free 6 months later (OR 1.3[0.7; 2.2] and 1.4 [0.8; 2.6] for medium and high readiness). High importance andhigh confidence were associated with being risk free (OR 0.9 [0.5; 1.8] and 2.9 [1.2;7.5] for medium and high importance; 2.1 [1.0;4.8] and 2.8 [1.5;5.6] for medium andhigh confidence). Among the 320 smokers, mean readiness, importance andconfidence to change smoking were 4.6 (2.6), 5.3 (2.6) and 5.9 (2.6). Neitherreadiness nor importance were associated with being smoking free (OR 2.1 [0.9; 4.7]and 2.1 [0.8; 5.8] for medium and high readiness; 1.4 [0.6; 3.4] and 2.1 [0.8; 5.4] formedium and high importance). High confidence was associated with being smokingfree (OR 2.2 [0.8;6.6] and 3.4 [1.2;9.8] for medium and high confidence).Conclusions: For drinking and smoking, high confidence in ability to change wasassociated -with similar magnitude- with a favorable outcome. This points to thevalue of confidence as an important predictor of successful change.

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This paper addresses the application of a PCA analysis on categorical data prior to diagnose a patients data set using a Case-Based Reasoning (CBR) system. The particularity is that the standard PCA techniques are designed to deal with numerical attributes, but our medical data set contains many categorical data and alternative methods as RS-PCA are required. Thus, we propose to hybridize RS-PCA (Regular Simplex PCA) and a simple CBR. Results show how the hybrid system produces similar results when diagnosing a medical data set, that the ones obtained when using the original attributes. These results are quite promising since they allow to diagnose with less computation effort and memory storage

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Global positioning systems (GPS) offer a cost-effective and efficient method to input and update transportation data. The spatial location of objects provided by GPS is easily integrated into geographic information systems (GIS). The storage, manipulation, and analysis of spatial data are also relatively simple in a GIS. However, many data storage and reporting methods at transportation agencies rely on linear referencing methods (LRMs); consequently, GPS data must be able to link with linear referencing. Unfortunately, the two systems are fundamentally incompatible in the way data are collected, integrated, and manipulated. In order for the spatial data collected using GPS to be integrated into a linear referencing system or shared among LRMs, a number of issues need to be addressed. This report documents and evaluates several of those issues and offers recommendations. In order to evaluate the issues associated with integrating GPS data with a LRM, a pilot study was created. To perform the pilot study, point features, a linear datum, and a spatial representation of a LRM were created for six test roadway segments that were located within the boundaries of the pilot study conducted by the Iowa Department of Transportation linear referencing system project team. Various issues in integrating point features with a LRM or between LRMs are discussed and recommendations provided. The accuracy of the GPS is discussed, including issues such as point features mapping to the wrong segment. Another topic is the loss of spatial information that occurs when a three-dimensional or two-dimensional spatial point feature is converted to a one-dimensional representation on a LRM. Recommendations such as storing point features as spatial objects if necessary or preserving information such as coordinates and elevation are suggested. The lack of spatial accuracy characteristic of most cartography, on which LRM are often based, is another topic discussed. The associated issues include linear and horizontal offset error. The final topic discussed is some of the issues in transferring point feature data between LRMs.

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PURPOSE: The purpose of this study was to analyze prognosis and treatment results for seminoma arising in corrected and uncorrected inguinal cryptorchidism (SCIC and SUIC). METHODS AND MATERIALS: We reviewed 66 patients with inguinal seminomas between June 1958 and December 1991 at the Cancer Hospital and Institute of Chinese Academy of Medical Sciences. Of these patients, 23 had prior orchiopexy and 43 presented with an inguinal form of cryptorchidism. At presentation, 17 of 66 (26%) patients had nodal metastases. This nodal involvement was 30% (7 of 23) for SCIC and 23% (10 of 43) for SUIC, respectively. These numbers are comparable with those in a series of patients treated for scrotal seminoma at our institution (26% vs. 20%). However, 3 of 23 (13%) patients who had prior orchiopexy presented with inguinal nodal metastasis as compared with 0 of 43 patients with SUIC or 4 of 237 patients with scrotal seminoma (p < .05). There were 49 stage I, 5 stage IIA, 8 stage IIB, 3 stage III, and 1 stage IV patients. All patients underwent radical orchiectomy and received further radiotherapy, chemotherapy, or both. Patients with stage I and stage II disease were treated primarily with radiotherapy, whereas patients with stage III and IV disease were treated with chemotherapy. RESULTS: The overall and disease-free survival at 5 and 10 years was 94% and 92%, 89% and 87%, respectively. The overall 5- and 10-year survival by stage was 100% and 100% for stage I, and 77% and 68% for stage II, respectively (p < .05). There was no significant difference in survival between SUIC and SCIC (93% vs. 96% at 5 years). Four patients developed relapse. Two of these four patients experienced relapse at the inguinal area, due to a marginal miss. Three of four patients with relapse were successfully salvaged, and one died of disease. CONCLUSION: Our results indicate that prognosis for inguinal seminoma is excellent and similar to that of scrotal seminoma. Postorchiectomy radiotherapy can be considered as the standard treatment for stage I and IIA inguinal seminoma. We recommend routinely including the para-aortic and ipsilateral pelvic nodes.

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PURPOSE OF THE STUDY: Fracture of the tibial pilon is a rare injury and its treatment remains difficult. The aim of this study was to report the complications and long term results of internal fixation using a technique which respects soft tissues and in which little material was used. MATERIAL: From 1985 to 1990, 48 patients with 51 fractures of the tibial pilon were treated by open reduction and internal fixation. All patients were submitted to a clinical and radiological review. METHODS: Both the Rüedi/Allgöwer and the AO-classification were used and determined by standard X-rays. Surgical procedure was performed with a 2 or 3 1/3 tube AO-plates and the peroneus was always fixed if fractured. Intraoperative reconstruction was analyzed. Subjective and objective scoring were used according to Olerud and Molander and the ankle arthritis was scored according to the classification determined by the SOFCOT in 1992. RESULTS: A minimal follow-up of 1 year for all cases was obtained, based on our own files. Thirty-eight patients (40 fractures) were evaluated after an average period of 88 months (56 to 124 months). Five patients developed cutaneous infection, three developed deep infection and four developed superficial skin necrosis. One aseptic non-union necessitated reoperation after 14 months. Two ankles had joint fusion after 19 and 25 months respectively due to severe arthritis. In six cases infectious and non-infectious complications led to surgical revision. According to the Olerud and Molander score, 15 per cent of the results were excellent, 45 per cent were good, 30 per cent were fair and 10 per cent poor. DISCUSSION: Literature shows a wide range of results following this surgical procedure. This is due to the difference in the type of trauma, classification system used, material used for the internal fixation and method of evaluation. The classification system of Rüedi and Allgöwer is the most commonly used but has a rather subjective tendency, especially between type II and type III. Treatment is difficult, especially for comminutive fractures associated with soft tissue damage. In this case, open reduction and internal fixation could increase iatrogenic lesions. For this reason surgical procedure can be delayed for several days, little material is used and soft tissue manipulation is reduced to minimum. In other study reports, the use of external fixation with or without minimal internal fixation have produced less complications without improving long term results. CONCLUSION: Analysis and comparison of study reports are difficult because of the absence of consensus in classification system and evaluation methods. The AO-classification, apparently the most objective, will probably be more and more used in the future. Treatment must be adapted to the bony lesion and soft tissue damage. Open reduction and internal fixation must be reserved for a specific group of lesion.

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Résumé -Caractéristiques architecturales des génomes bactériens et leurs applications Les bactéries possèdent généralement un seul chromosome circulaire. A chaque génération, ce chromosome est répliqué bidirectionnellement, par deux complexes enzymatiques de réplication se déplaçant en sens opposé depuis l'origine de réplication jusqu'au terminus, situé à l'opposé. Ce mode de réplication régit l'architecture du chromosome -l'orientation des gènes par rapport à la réplication, notamment - et est en grande partie à l'origine des pressions qui provoquent la variation de la composition en nucléotides du génome, hors des contraintes liées à la structure et à la fonction des protéines codées sur le chromosome. Le but de cette thèse est de contribuer à quantifier les effets de la réplication sur l'architecture chromosomique, en s'intéressant notamment aux gènes des ARN ribosomiques, cruciaux pour la bactérie. D'un autre côté, cette architecture est spécifique à l'espèce et donne ainsi une «identité génomique » aux gènes. Il est démontré ici qu'il est possible d'utiliser des marqueurs «naïfs » de cette identité pour détecter, notamment dans le génome du staphylocoque doré, des îlots de pathogénicité, qui concentrent un grand nombre de facteurs de virulence de la bactérie. Ces îlots de pathogénicité sont mobiles, et peuvent passer d'une bactérie à une autre, mais conservent durant un certain temps l'identité génomique de leur hôte précédent, ce qui permet de les reconnaître dans leur nouvel hôte. Ces méthodes simples, rapides et fiables seront de la plus haute importance lorsque le séquençage des génomes entiers sera rapide et disponible à très faible coût. Il sera alors possible d'analyser instantanément les déterminants pathogéniques et de résistance aux antibiotiques des agents pathogènes. Summary The bacterial genome is a highly organized structure, which may be referred to as the genome architecture, and is mainly directed by DNA replication. This thesis provides significant insights in the comprehension of the forces that shape bacterial chromosomes, different in each genome and contributing to confer them an identity. First, it shows the importance of the replication in directing the orientation of prokaryotic ribosomal RNAs, and how it shapes their nucleotide composition in a tax on-specific manner. Second, it highlights the pressure acting on the orientation of the genes in general, a majority of which are transcribed in the same direction as replication. Consequently, apparent infra-arm genome rearrangements, involving an exchange of the leading/lagging strands and shown to reduce growth rate, are very likely artifacts due to an incorrect contig assembly. Third, it shows that this genomic identity can be used to detect foreign parts in genomes, by establishing this identity for a given host and identifying the regions that deviate from it. This property is notably illustrated with Staphylococcus aureus: known pathogenicity islands and phages, and putative ancient pathogenicity islands concentrating many known pathogenicity-related genes are highlighted; the analysis also detects, incidentally, proteins responsible for the adhesion of S. aureus to the hosts' cells. In conclusion, the study of nucleotide composition of bacterial genomes provides the opportunity to better understand the genome-level pressures that shape DNA sequences, and to identify genes and regions potentially related to pathogenicity with fast, simple and reliable methods. This will be of crucial importance when whole-genome sequencing will be a rapid, inexpensive and routine tool.

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The coarse aggregates used for Portland Cement concrete in southwest Iowa have exhibited a poor serviceability. This early failure is attributed to a characteristic commonly referred as "D" cracking. "D" line cracking is a discolored area of concrete caused by many fine, parallel hairline cracks. "D" line cracking is primarily caused by the movement of water in and through coarse aggregate with a unique pore structure. The presence of the water in the aggregates at the time of freezing causes the "D" cracking to occur and early failure. By making the pore structure less permeable to moisture, it is thought the durability factor of the concrete should increase. By drying the aggregate before mixing and then mixing with the cement, the particles of cement should enter the outer pore structure, and upon hydration make the pore structure less permeable to moisture.

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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.