974 resultados para determining factors


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Associations between socio-demographic factors, water contact patterns and Schistosoma mansoni infection were investigated in 506 individuals (87% of inhabitants over 1 year of age) in an endemic area in Brazil (Divino), aiming at determining priorities for public health measures to prevent the infection. Those who eliminated S. mansoni eggs (n = 198) were compared to those without eggs in the stools (n = 308). The following explanatory variables were considered: age, sex, color, previous treatment with schistosomicide, place of birth, quality of the houses, water supply for the household, distance from houses to stream, and frequency and reasons for water contact. Factors found to be independently associated with the infection were age (10-19 and > 20 yrs old), and water contact for agricultural activities, fishing, and swimming or bathing (Adjusted relative odds = 5.0, 2.4, 3.2, 2.1 and 2.0, respectively). This suggests the need for public health measures to prevent the infection, emphasizing water contact for leisure and agricultural activities in this endemic area.

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With increasing technological innovation, the concept of marketing and its applications become more functional and wide. Today, we witness a steady growth in the development of mobile marketing campaigns, i.e., marketing campaigns targeting mobile devices (mobile phones, Smartphones, PDAs, tablets). Among the several mobile technologies available (Bluetooth networks, Wi-Fi, WAP, SMS service, MMS), Bluetooth seems to have the biggest potential for the least invasive consumer mobile marketing strategy. This study seeks to answer the question "what factors may motivate the Portuguese consumer to accept Bluetooth marketing?.“ We propose a conceptual model capable of investigating the relationships between the several responsiveness factors to Bluetooth marketing. The development of a set of hypotheses supported by an online questionnaire to a valid sample of 755 participants, demonstrates that there is a relationship between factors such as expanded knowledge of the technology, and Bluetooth marketing receptivity. Additionally, we find that the information value of mobile advertising messages, such as entertainment value and personalization, relates well to responsiveness. The ability to accept/dismiss promotional messages sent to mobile phones and other safety features also correlated well with Bluetooth marketing receptivity.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

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Introduction: In Brazil, hantavirus cardiopulmonary syndrome (HCPS) has a high lethality rate that varies by region. This study aimed to identify the risk factors associated with fatal hantavirosis. Methods: This study was a case-control study that included all laboratory confirmed cases of hantavirosis. The cases were stratified by the different Brazilian regions using data from the Notifiable Diseases Information System. “Cases” were patients who progressed to death, whereas “controls” were patients who were cured. The odds ratio (OR) and the adjusted OR were calculated. Results: Overall, 158 cases and 281 controls were included in this study. In the Midwest region, the cases were 60% less likely to present with flank pain, and the time between the beginning of symptoms and death was shorter than the time between the beginning of symptoms and a cure. In the Southeast region, the cases were 60% less likely to present with thrombocytopenia or reside in rural areas compared to those who progressed to a cure. Additionally, the cases sought medical assistance, notification and investigation more quickly than the controls. In the Southern region, the cases that died were 70% less likely to be male compared to the controls. Conclusions: HCPS manifests with nonspecific symptoms, and there are few published studies related to the condition, so determining a patient's therapeutic strategy is difficult. This study presents findings from different Brazilian regions and highlights the need for further investigations to improve comprehension about regional risk factors associated with hantavirosis and to reduce morbimortality.

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RESUMO: Resumo Uma prestação de serviços de saúde mental para crianças e adolescentes (CAMHS) oportuna, eficaz e baseada na evidência pode evitar incapacidade a longo prazo. No entanto, estes serviços são criticamente sub-financiados em todo o mundo. É um imperativo garantir que este precioso recurso não seja desperdiçado. Os governos e outras partes interessadas relevantes na área da saúde mental precisam de conhecer o estado de saúde mental da população, quais os recursos disponíveis e como melhor utilizar os recursos disponíveis para orientar uma política e decisões efectivas sobre os níveis de serviços. Objetivo: O objetivo deste artigo é explorar o papel da acuidade, gravidade e complexidade na determinação dos cuidados em saúde mental especializados recebidos por crianças e adolescentes que sofrem perturbações mentais. Métodos: Este estudo é exploratório envolvendo uma revisão sistemática da literatura. Foi realizada uma pesquisa com palavras-chave utilizando bases de dados PsychINFO, EMBASE, PubMed e MEDLINE. A literatura cinzenta também foi investigada com um enfoque nas abordagens sistémicas, organizacionais e políticas para a organização e comissionamento de CAMHS. Foram selecionados apenas documentos escritos em Inglês. Três países, Bélgica, Reino Unido e Estados Unidos, todos eles com modelos muito diferentes de organização de CAMHS, foram revistos para investigar de que forma os conceitos de acuidade, gravidade e complexidade foram utilizados na sua concepção de serviços para determinar o nível da assistência prestada. Resultados: Nem a Bélgica, nem o modelo norte-americano de CAMHS organização de serviço parecem estar alinhados com os principais conceitos na determinação do nível de prestação de serviços. O sistema de serviços do Reino Unido de CAMHS está mais estreitamente alinhado com esses conceitos e tem uma alocação de recursos mais equilibrada entre o hospital e a comunidade. O seu ponto fraco está na falta de flexibilidade entre os níveis de serviço e na falta de apoio para com o sector dos cuidados de saúde primários. Conclusões: A variabilidade na alocação de recursos a diferentes níveis especializados de CAMHS (em regime de internamento, ambulatório, e na comunidade) e o modelo diferente de estrutura de serviços entre os países estudados indica uma inconsistência na forma como as crianças e adolescentes que apresentam aos CAMHS são referenciados para os cuidados que recebem. Isto põe em questão se as crianças e adolescentes com perturbações mentais estão a receber o nível e tipo de cuidados concordantes com as suas necessidades. A concepção e o comissionamento de sistemas de CAMHS levam-nos à discussão de uma série de princípios fundamentais que devem ser considerados. O sistema perfeito no entanto, ainda está para ser encontrado. -------------------------------- ABSTRACT: Provision of timely, effective, evidence based mental health services to children and adolescents can prevent long term impairment, but they are critically underfunded across the globe. There is an imperative to ensure this precious resource is not wasted. Governments and other relevant mental health stakeholders need to know the mental health status of the population, what resources are available and how best to use the resources available to guide effective policy and decisions about service levels. Aim: The aim of this paper is to explore the role of acuity, severity and complexity in determining the specialist mental health care that children and adolescents experiencing mental disorders receive. Methods: This study is exploratory involving a systematic scan of the literature. A key word search was conducted using databases PSYCHINFO, EMBASE, PUBMED and MEDLINE. Grey literature was also searched to focus on systemic, organisational and policy approaches to the organisation and commissioning of CAMHS. Only documents written in English were selected. Three countries Belgium, UK and the US all with very different models of service organisation for CAMHS were reviewed to investigate how well the concepts of acuity, severity and complexity were used to determine the level of care delivered in their service design. Findings: Neither the Belgium nor the US model of CAMHS service organisation appear to align with the key concepts driving intensity of level of service provision. The UK CAMHS service system most closely aligns with the concepts. It has a more balanced resource allocation between hospital and community. Its downfall is in its lack of flexibility between service levels and its lack of support for the primary care sector. Conclusions: The variability in resource allocation to different service levels (inpatient, outpatient, community) within specialist CAMHS and the differing model of service structure across countries indicates an inconsistency in how children and adolescents presenting to CAMHS are allocated to the care they receive. This puts into question whether children and adolescent with mental disorders are receiving a level and type of care commensurate with their needs. In commissioning and designing CAMHS systems a number of key principles that should be considered are discussed. The perfect system however, is yet to be found.

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Background/Purpose: The aims of this study were to determine the incidence of persistent gastrocutaneous fistulas (GCF) after gastrostomy removal and to identify associated risk factors. Methods: This retrospective study included 75 children from the Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland who had a gastrostomy performed between 1988 and 2010. The records of the children were reviewed for sex, age at the time of gastrostomy removal, underlying disease, type of gastrostomy placement and length of use, and then analyzed in order to find a correlation between the GCF and these parameters. Results: The gastrostomy orifice did not close spontaneously within the first month in 33 of the patients (44%), and 15 subsequently underwent surgical closure. The mean duration of gastrostomy use was significantly longer in children who developed a persistent GCF (30 vs. 19 months, P = 0.03). The other parameters studied did not show any significant association with the persistence of a GCF. Conclusions: The only predictive factor determining the persistence of a GCF was found to be the timespan between the placement and removal of the gastrostomy appliance. Elective surgical closure of the gastrostomy orifice should be considered after 1 month of persistent GCF.

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Summary : Division of labour is one of the most fascinating aspects of social insects. The efficient allocation of individuals to a multitude of different tasks requires a dynamic adjustment in response to the demands of a changing environment. A considerable number of theoretical models have focussed on identifying the mechanisms allowing colonies to perform efficient task allocation. The large majority of these models are built on the observation that individuals in a colony vary in their propensity (response threshold) to perform different tasks. Since individuals with a low threshold for a given task stimulus are more likely to perform that task than individuals with a high threshold, infra-colony variation in individual thresholds results in colony division of labour. These theoretical models suggest that variation in individual thresholds is affected by the within-colony genetic diversity. However, the models have not considered the genetic architecture underlying the individual response thresholds. This is important because a better understanding of division of labour requires determining how genotypic variation relates to differences in infra-colony response threshold distributions. In this thesis, we investigated the combined influence on task allocation efficiency of both, the within-colony genetic variability (stemming from variation in the number of matings by queens) and the number of genes underlying the response thresholds. We used an agent-based simulator to model a situation where workers in a colony had to perform either a regulatory task (where the amount of a given food item in the colony had to be maintained within predefined bounds) or a foraging task (where the quantity of a second type of food item collected had to be the highest possible). The performance of colonies was a function of workers being able to perform both tasks efficiently. To study the effect of within-colony genetic diversity, we compared the performance of colonies with queens mated with varying number of males. On the other hand, the influence of genetic architecture was investigated by varying the number of loci underlying the response threshold of the foraging and regulatory tasks. Artificial evolution was used to evolve the allelic values underlying the tasks thresholds. The results revealed that multiple matings always translated into higher colony performance, whatever the number of loci encoding the thresholds of the regulatory and foraging tasks. However, the beneficial effect of additional matings was particularly important when the genetic architecture of queens comprised one or few genes for the foraging task's threshold. By contrast, higher number of genes encoding the foraging task reduced colony performance with the detrimental effect being stronger when queens had mated with several males. Finally, the number of genes determining the threshold for the regulatory task only had a minor but incremental effect on colony performance. Overall, our numerical experiments indicate the importance of considering the effects of queen mating frequency, genetic architecture underlying task thresholds and the type of task performed when investigating the factors regulating the efficiency of division of labour in social insects. In this thesis we also investigate the task allocation efficiency of response threshold models and compare them with neural networks. While response threshold models are widely used amongst theoretical biologists interested in division of labour in social insects, our simulation reveals that they perform poorly compared to a neural network model. A major shortcoming of response thresholds is that they fail at one of the most crucial requirement of division of labour, the ability of individuals in a colony to efficiently switch between tasks under varying environmental conditions. Moreover, the intrinsic properties of the threshold models are that they lead to a large proportion of idle workers. Our results highlight these limitations of the response threshold models and provide an adequate substitute. Altogether, the experiments presented in this thesis provide novel contributions to the understanding of how division of labour in social insects is influenced by queen mating frequency and genetic architecture underlying worker task thresholds. Moreover, the thesis also provides a novel model of the mechanisms underlying worker task allocation that maybe more generally applicable than the widely used response threshold models. Resumé : La répartition du travail est l'un des aspects les plus fascinants des insectes vivant en société. Une allocation efficace de la multitude de différentes tâches entre individus demande un ajustement dynamique afin de répondre aux exigences d'un environnement en constant changement. Un nombre considérable de modèles théoriques se sont attachés à identifier les mécanismes permettant aux colonies d'effectuer une allocation efficace des tâches. La grande majorité des ces modèles sont basés sur le constat que les individus d'une même colonie diffèrent dans leur propension (inclination à répondre) à effectuer différentes tâches. Etant donné que les individus possédant un faible seuil de réponse à un stimulus associé à une tâche donnée sont plus disposés à effectuer cette dernière que les individus possédant un seuil élevé, les différences de seuils parmi les individus vivant au sein d'une même colonie mènent à une certaine répartition du travail. Ces modèles théoriques suggèrent que la variation des seuils des individus est affectée par la diversité génétique propre à la colonie. Cependant, ces modèles ne considèrent pas la structure génétique qui est à la base des seuils de réponse individuels. Ceci est très important car une meilleure compréhension de la répartition du travail requière de déterminer de quelle manière les variations génotypiques sont associées aux différentes distributions de seuils de réponse à l'intérieur d'une même colonie. Dans le cadre de cette thèse, nous étudions l'influence combinée de la variabilité génétique d'une colonie (qui prend son origine dans la variation du nombre d'accouplements des reines) avec le nombre de gènes supportant les seuils de réponse, vis-à-vis de la performance de l'allocation des tâches. Nous avons utilisé un simulateur basé sur des agents pour modéliser une situation où les travailleurs d'une colonie devaient accomplir une tâche de régulation (1a quantité d'une nourriture donnée doit être maintenue à l'intérieur d'un certain intervalle) ou une tâche de recherche de nourriture (la quantité d'une certaine nourriture doit être accumulée autant que possible). Dans ce contexte, 'efficacité des colonies tient en partie des travailleurs qui sont capable d'effectuer les deux tâches de manière efficace. Pour étudier l'effet de la diversité génétique d'une colonie, nous comparons l'efficacité des colonies possédant des reines qui s'accouplent avec un nombre variant de mâles. D'autre part, l'influence de la structure génétique a été étudiée en variant le nombre de loci à la base du seuil de réponse des deux tâches de régulation et de recherche de nourriture. Une évolution artificielle a été réalisée pour évoluer les valeurs alléliques qui sont à l'origine de ces seuils de réponse. Les résultats ont révélé que de nombreux accouplements se traduisaient toujours en une plus grande performance de la colonie, quelque soit le nombre de loci encodant les seuils des tâches de régulation et de recherche de nourriture. Cependant, les effets bénéfiques d'accouplements additionnels ont été particulièrement important lorsque la structure génétique des reines comprenait un ou quelques gènes pour le seuil de réponse pour la tâche de recherche de nourriture. D'autre part, un nombre plus élevé de gènes encodant la tâche de recherche de nourriture a diminué la performance de la colonie avec un effet nuisible d'autant plus fort lorsque les reines s'accouplent avec plusieurs mâles. Finalement, le nombre de gènes déterminant le seuil pour la tâche de régulation eu seulement un effet mineur mais incrémental sur la performance de la colonie. Pour conclure, nos expériences numériques révèlent l'importance de considérer les effets associés à la fréquence d'accouplement des reines, à la structure génétique qui est à l'origine des seuils de réponse pour les tâches ainsi qu'au type de tâche effectué au moment d'étudier les facteurs qui régulent l'efficacité de la répartition du travail chez les insectes vivant en communauté. Dans cette thèse, nous étudions l'efficacité de l'allocation des tâches des modèles prenant en compte des seuils de réponses, et les comparons à des réseaux de neurones. Alors que les modèles basés sur des seuils de réponse sont couramment utilisés parmi les biologistes intéressés par la répartition des tâches chez les insectes vivant en société, notre simulation montre qu'ils se révèlent peu efficace comparé à un modèle faisant usage de réseaux de neurones. Un point faible majeur des seuils de réponse est qu'ils échouent sur un point crucial nécessaire à la répartition des tâches, la capacité des individus d'une colonie à commuter efficacement entre des tâches soumises à des conditions environnementales changeantes. De plus, les propriétés intrinsèques des modèles basés sur l'utilisation de seuils conduisent à de larges populations de travailleurs inactifs. Nos résultats mettent en évidence les limites de ces modèles basés sur l'utilisation de seuils et fournissent un substitut adéquat. Ensemble, les expériences présentées dans cette thèse fournissent de nouvelles contributions pour comprendre comment la répartition du travail chez les insectes vivant en société est influencée par la fréquence d'accouplements des reines ainsi que par la structure génétique qui est à l'origine, pour un travailleur, du seuil de réponse pour une tâche. De plus, cette thèse fournit également un nouveau modèle décrivant les mécanismes qui sont à l'origine de l'allocation des tâches entre travailleurs, mécanismes qui peuvent être appliqué de manière plus générale que ceux couramment utilisés et basés sur des seuils de réponse.

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Clinical and laboratory risk factors for death from visceral leishmaniasis (VL) are relatively known, but quantitative real-time polymerase chain reaction (qPCR) might assess the role of parasite load in determining clinical outcome. The aim of this study was to identify risk factors, including parasite load in peripheral blood, for VL poor outcome among children. This prospective cohort study evaluated children aged ≤ 12 years old with VL diagnosis at three times: pre-treatment (T0), during treatment (T1) and post-treatment (T2). Forty-eight patients were included and 16 (33.3%) met the criteria for poor outcome. Age ≤ 12 months [relative risk (RR) 3.51; 95% confidence interval (CI) 1.89-6.52], tachydyspnoea (RR 3.46; 95% CI 2.19-5.47), bacterial infection (RR 3.08; 95% CI 1.27-7.48), liver enlargement (RR 3.00; 95% CI 1.44-6.23) and low serum albumin (RR 7.00; 95% CI 1.80-27.24) were identified as risk factors. qPCR was positive in all patients at T0 and the parasite DNA was undetectable in 76.1% of them at T1 and in 90.7% at T2. There was no statistical association between parasite load at T0 and poor outcome.

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American cutaneous leishmaniasis (ACL) is a vector-transmitted infectious disease with an estimated 1.5 million new cases per year. In Brazil, ACL represents a significant public health problem, with approximately 30,000 new reported cases annually, representing an incidence of 18.5 cases per 100,000 inhabitants. Corte de Pedra is in a region endemic for ACL in the state of Bahia (BA), northeastern Brazil, with 500-1,300 patients treated annually. Over the last decade, population and family-based candidate gene studies were conducted in Corte de Pedra, founded on previous knowledge from studies on mice and humans. Notwithstanding limitations related to sample size and power, these studies contribute important genetic biomarkers that identify novel pathways of disease pathogenesis and possible new therapeutic targets. The present paper is a narrative review about ACL immunogenetics in BA, highlighting in particular the interacting roles of the wound healing gene FLI1 with interleukin-6 and genes SMAD2 and SMAD3 of the transforming growth factor beta signalling pathway. This research highlights the need for well-powered genetic and functional studies on Leishmania braziliensis infection as essential to define and validate the role of host genes in determining resistance/susceptibility regarding this disease.

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It is currently suspected that sugar overconsumption, and more specifically fructose, may promote the development of obesity and of several cardio-metabolic disorders. However, environmental factors, such as fish oil and dietary proteins, may prevent some deleterious effects of fructose. The aim of this thesis was to identify potential environmental factors that may modulate the metabolic effects of fructose. The first study was designed to evaluate the impact of endurance exercise in healthy young men fed a high-fructose, isocaloric diet. Fructose-induced effects on lipid profile were totally prevented by endurance exercise and may be explained by an enhanced clearance of TRL-TG and the inhibition of de novo lipogenesis. As energy intake was adjusted to energy requirement, we can conclude that exercise acts on fructose metabolism independently of energy imbalance. The second study aimed at determining whether coffee and more specifically chlorogenic acid consumption may prevent fructose-induced intrahepatic lipids accumulation, hypertriglyceridemia and hepatic insulin resistance, through a stimulation of lipid oxidation. Coffee did not prevent the fructose-induced increase in IHCL or plasma TG. Interestingly, the three coffees tested prevented the decrease in hepatic insulin sensitivity, independently of their content in caffeine or chlorogenic acid. Finally, in the third study, we evaluated the effect of essential amino acid supplementation on the increase of hepatic lipids induced by a high-fructose diet. This intervention slightly decreased IHCL concentration. The exact mechanisms remain unidentified but may involve an increased secretion of VLDL-TG. In conclusion, the environmental factors evaluated allow to prevent some of the deleterious effects of fructose and suggest that recommendations on fructose consumption should also take into account environmental factors.

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Density is an important component of hot-mix asphalt (HMA) pavement quality and long-term performance. Insufficient density of an in-place HMA pavement is the most frequently cited construction-related performance problem. This study evaluated the use of electromagnetic gauges to nondestructively determine densities. Field and laboratory measurements were taken with two electromagnetic gauges—a PaveTracker and a Pavement Quality Indicator (PQI). Test data were collected in the field during and after paving operations and also in a laboratory on field mixes compacted in the lab. This study revealed that several mix- and project-specific factors affect electromagnetic gauge readings. Consequently, the implementation of these gauges will likely need to be done utilizing a test strip on a project- and mix-specific basis to appropriately identify an adjustment factor for the specific electromagnetic gauge being used for quality control and quality assurance (QC/QA) testing. The substantial reduction in testing time that results from employing electromagnetic gauges rather than coring makes it possible for more readings to be used in the QC/QA process with real-time information without increasing the testing costs.

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Background: The goal of the present study was to retrospectively analyze our series of parasagittal meningiomas, treated by either single or combined therapies (surgery and/or SRS and FSRT), in order to determine the factors that influence patient outcome. Methods: Between January 1999 and May 2007, 37 parasagittal meningiomas were treated in our center. We compared the outcome of the parasagittal meningiomas in relation to the treatment and adjuvant treatment given, their location along the SSS, their volume, their histological and resection grade as well as the patient's sex and age to understand which factors influenced their natural history. Findings: Median follow-up was 6.7 years (2.4-12 years). Tumor grades and Simpson resection grade were distributed evenly along the SSS. The actuarial overall tumor control rate was 65.9%. Regression analysis showed, that the tumor histological grade and the Simpson resection grade were two significant factors in determining the tumor control (p<0.002 and p<0.008). Location along the SSS showed a lower control rate in the posterior third (p<0.002). Sex, age and tumor volume, however, were not significant factors. Moreover, and unexpectedly, the In our series, the proportion of adjuvant treatment was much higher than in former described series (39% vs 7%) but with similar control rate and lower morbidity and mortality. Conclusions: In our series, histological grade and Simpson grade are independent factors for recurrence and tumor control. Interestingly, location in the posterior third of the SSS seems to be another independent factor for recurrence. In order to avoid major morbidities related to surgery we advocate earlier use of adjuvant therapies for higher histological grade tumors and for tumors located at the posterior portion of the SSS, but definitive conclusions might warrant a larger series.

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Density is an important component of hot-mix asphalt (HMA) pavement quality and long-term performance. Insufficient density of an in-place HMA pavement is the most frequently cited construction-related performance problem. This study evaluated the use of electromagnetic gauges to nondestructively determine densities. Field and laboratory measurements were taken with two electromagnetic gauges—a PaveTracker and a Pavement Quality Indicator (PQI). Test data were collected in the field during and after paving operations and also in a laboratory on field mixes compacted in the lab. This study revealed that several mix- and project-specific factors affect electromagnetic gauge readings. Consequently, the implementation of these gauges will likely need to be done utilizing a test strip on a project- and mix-specific basis to appropriately identify an adjustment factor for the specific electromagnetic gauge being used for quality control and quality assurance (QC/QA) testing. The substantial reduction in testing time that results from employing electromagnetic gauges rather than coring makes it possible for more readings to be used in the QC/QA process with real-time information without increasing the testing costs.

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The Road Rater is a dynamic deflection measuring apparatus for flexible base pavements. The Road Rater replaces the Benkelman Beam which was last used by the Iowa DOT in 1977. Road Rater test results correlate reasonably well (correlation coefficient = 0.83) with Benkelman Beam test data. The basic differences between the Road Rater and Benkelman Beam are as follows: 1. The Benkelman Beam uses a static 18,000 lb. load while the Road Rater uses a dynamic 800 to 2,000 lb. loading. 2. The Road Rater tests much faster and more economically than the Benkelman Beam. 3. The Road Rater better simulates a moving truck than the Benkelman Beam. The basic operating principle of the Road Rater is to impart a dynamic loading and measure the resultant movement of the pavement with velocity sensors. This data, when properly adjusted for temperature by use of a nomograph included in this report, can be used to determine pavement life expectancy and estimate overlay thickness required. Road Rater testing will be conducted in the spring, when pavements are in their weakest condition, until seasonal correction factors can be developed. The Road Rater does not have sufficient ram weight to effectively evaluate load carrying capacity of rigid pavements. All rigid pavements react similarly to Road Rater testing and generally deflect from 0.65 to 1.30 mils. Research will be contined to evaluate rigid pavements with the Road Rater, however. The Road Rater has proven to be a reliable, troublefree pavement evaluation machine. The deflection apparatus was originally front-mounted,but was rear-mounted during the winter of 1977-78. Since that time, van handling has greatly improved, and front suspension parts are no longer overstressed due to improper weight distribution.

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ABSTRACT: BACKGROUND: The Psychiatric arm of the population-based CoLaus study (PsyCoLaus) is designed to: 1) establish the prevalence of threshold and subthreshold psychiatric syndromes in the 35 to 66 year-old population of the city of Lausanne (Switzerland); 2) test the validity of postulated definitions for subthreshold mood and anxiety syndromes; 3) determine the associations between psychiatric disorders, personality traits and cardiovascular diseases (CVD), 4) identify genetic variants that can modify the risk for psychiatric disorders and determine whether genetic risk factors are shared between psychiatric disorders and CVD. This paper presents the method as well as somatic and sociodemographic characteristics of the sample. METHODS: All 35 to 66 year-old persons previously selected for the population-based CoLaus survey on risk factors for CVD were asked to participate in a substudy assessing psychiatric conditions. This investigation included the Diagnostic Interview for Genetic Studies to elicit diagnostic criteria for threshold disorders according to DSM-IV and algorithmically defined subthreshold syndromes. Complementary information was gathered on potential risk and protective factors for psychiatric disorders, migraine and on the morbidity of first-degree family members, whereas the collection of DNA and plasma samples was part of the original somatic study (CoLaus). RESULTS: A total of 3,691 individuals completed the psychiatric evaluation (67% participation). The gender distribution of the sample did not differ significantly from that of the general population in the same age range. Although the youngest 5-year band of the cohort was underrepresented and the oldest 5-year band overrepresented, participants of PsyCoLaus and individuals who refused to participate revealed comparable scores on the General Health Questionnaire, a self-rating instrument completed at the somatic exam. CONCLUSIONS: Despite limitations resulting from the relatively low participation in the context of a comprehensive and time-consuming investigation, the PsyCoLaus study should significantly contribute to the current understanding of psychiatric disorders and comorbid somatic conditions by: 1) establishing the clinical relevance of specific psychiatric syndromes below the DSM-IV threshold; 2) determining comorbidity between risk factors for CVD and psychiatric disorders; 3) assessing genetic variants associated with common psychiatric disorders and 4) identifying DNA markers shared between CVD and psychiatric disorders.