921 resultados para 760200 Environmental and Resource Evaluation


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Recent data compiled by the National Bridge Inventory revealed 29% of Iowa's approximate 24,600 bridges were either structurally deficient or functionally obsolete. This large number of deficient bridges and the high cost of needed repairs create unique problems for Iowa and many other states. The research objective of this project was to determine the load capacity of a particular type of deteriorating bridge – the precast concrete deck bridge – which is commonly found on Iowa's secondary roads. The number of these precast concrete structures requiring load postings and/or replacement can be significantly reduced if the deteriorated structures are found to have adequate load capacity or can be reliably evaluated. Approximately 600 precast concrete deck bridges (PCDBs) exist in Iowa. A typical PCDB span is 19 to 36 ft long and consists of eight to ten simply supported precast panels. Bolts and either a pipe shear key or a grouted shear key are used to join adjacent panels. The panels resemble a steel channel in cross-section; the web is orientated horizontally and forms the roadway deck and the legs act as shallow beams. The primary longitudinal reinforcing steel bundled in each of the legs frequently corrodes and causes longitudinal cracks in the concrete and spalling. The research team performed service load tests on four deteriorated PCDBs; two with shear keys in place and two without. Conventional strain gages were used to measure strains in both the steel and concrete, and transducers were used to measure vertical deflections. Based on the field results, it was determined that these bridges have sufficient lateral load distribution and adequate strength when shear keys are properly installed between adjacent panels. The measured lateral load distribution factors are larger than AASHTO values when shear keys were not installed. Since some of the reinforcement had hooks, deterioration of the reinforcement has a minimal affect on the service level performance of the bridges when there is minimal loss of cross-sectional area. Laboratory tests were performed on the PCDB panels obtained from three bridge replacement projects. Twelve deteriorated panels were loaded to failure in a four point bending arrangement. Although the panels had significant deflections prior to failure, the experimental capacity of eleven panels exceeded the theoretical capacity. Experimental capacity of the twelfth panel, an extremely distressed panel, was only slightly below the theoretical capacity. Service tests and an ultimate strength test were performed on a laboratory bridge model consisting of four joined panels to determine the effect of various shear connection configurations. These data were used to validate a PCDB finite element model that can provide more accurate live load distribution factors for use in rating calculations. Finally, a strengthening system was developed and tested for use in situations where one or more panels of an existing PCDB need strengthening.

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The objective of this work was to evaluate isoflavone concentrations in seeds of different Brazilian soybean cultivars grown in a range of locations and environmental conditions in Brazil. Seeds of 233 cultivars grown in Ponta Grossa, PR, Brazil, during the 2001/2002 soybean season, and of 22 cultivars sown in different locations of Brazilian Northeast, Southeast on South regions were analyzed for total isoflavones, including daidzin, glycitin, genistin and acetylgenistin. The total isoflavones ranged from 12 mg 100 g-1 (cv. Embrapa 48) to 461 mg 100 g-1 (cv. CS 305) among the 233 cultivars grown in Ponta Grossa, and the differences among them are due to genetic effects since all cultivars were grown and collected at the same locatation and year. This is an indication of the possibility of breeding for isoflavone content. Differences in isoflavone content observed in the cultivars grown in different locations permit the selection of locations for optimum isoflavone content (low or high), depending on the uses of soybean. In the Northeast region (5-8°S), higher concentrations of total isoflavones were observed at São Raimundo das Mangabeiras (232 mg 100 g-1) and Tasso Fragoso (284 mg 100 g-1) municipalities, and in the South (23-30°S), isoflavones were higher in Guarapuava, Canoinhas, Vacaria and Campos Novos municipalities, ranging from 130 to 409 mg 100 g-1.

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Résumé Ce travail de thèse étudie des moyens de formalisation permettant d'assister l'expert forensique dans la gestion des facteurs influençant l'évaluation des indices scientifiques, tout en respectant des procédures d'inférence établies et acceptables. Selon une vue préconisée par une partie majoritaire de la littérature forensique et juridique - adoptée ici sans réserve comme point de départ - la conceptualisation d'une procédure évaluative est dite 'cohérente' lors qu'elle repose sur une implémentation systématique de la théorie des probabilités. Souvent, par contre, la mise en oeuvre du raisonnement probabiliste ne découle pas de manière automatique et peut se heurter à des problèmes de complexité, dus, par exemple, à des connaissances limitées du domaine en question ou encore au nombre important de facteurs pouvant entrer en ligne de compte. En vue de gérer ce genre de complications, le présent travail propose d'investiguer une formalisation de la théorie des probabilités au moyen d'un environment graphique, connu sous le nom de Réseaux bayesiens (Bayesian networks). L'hypothèse principale que cette recherche envisage d'examiner considère que les Réseaux bayesiens, en concert avec certains concepts accessoires (tels que des analyses qualitatives et de sensitivité), constituent une ressource clé dont dispose l'expert forensique pour approcher des problèmes d'inférence de manière cohérente, tant sur un plan conceptuel que pratique. De cette hypothèse de travail, des problèmes individuels ont été extraits, articulés et abordés dans une série de recherches distinctes, mais interconnectées, et dont les résultats - publiés dans des revues à comité de lecture - sont présentés sous forme d'annexes. D'un point de vue général, ce travail apporte trois catégories de résultats. Un premier groupe de résultats met en évidence, sur la base de nombreux exemples touchant à des domaines forensiques divers, l'adéquation en termes de compatibilité et complémentarité entre des modèles de Réseaux bayesiens et des procédures d'évaluation probabilistes existantes. Sur la base de ces indications, les deux autres catégories de résultats montrent, respectivement, que les Réseaux bayesiens permettent également d'aborder des domaines auparavant largement inexplorés d'un point de vue probabiliste et que la disponibilité de données numériques dites 'dures' n'est pas une condition indispensable pour permettre l'implémentation des approches proposées dans ce travail. Le présent ouvrage discute ces résultats par rapport à la littérature actuelle et conclut en proposant les Réseaux bayesiens comme moyen d'explorer des nouvelles voies de recherche, telles que l'étude de diverses formes de combinaison d'indices ainsi que l'analyse de la prise de décision. Pour ce dernier aspect, l'évaluation des probabilités constitue, dans la façon dont elle est préconisée dans ce travail, une étape préliminaire fondamentale de même qu'un moyen opérationnel.

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The function of dowel bars is the transfer of a load across the transverse joint from one pavement slab to the adjoining slab. In the past, these transfer mechanisms have been made of steel. However, pavement damage such as loss of bonding, deterioration, hollowing, cracking and spalling start to occur when the dowels begin to corrode. A significant amount of research has been done to evaluate alternative types of materials for use in the reinforcement of concrete pavements. Initial findings have indicated that stainless steel and fiber composite materials possess properties, such as flexural strength and corrosion resistance, that are equivalent to the Department of Transportation specifications for standard steel, 1 1/2 inch diameter dowel bars. Several factors affect the load transfer of dowels; these include diameter, alignment, grouting, bonding, spacing, corrosion resistance, joint spacing, slab thickness and dowel embedment length. This research is directed at the analysis of load transfer based on material type and dowel spacing. Specifically, this research is directed at analyzing the load transfer characteristics of: (a) 8-inch verses 12-inch spacing, and (b) alternative dowel material compared to epoxy coated steel dowels, will also be analyzed. This report documents the installation of the test sections, placed in 1997. Dowel material type and location are identified. Construction observations and limitations with each dowel material are shown.

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Malaria, a disease of worldwide significance, is responsible for over one million deaths annually. The liver-stage of Plasmodium's life cycle is the first, obligatory, but clinically silent step in malaria infection. The P. falciparum type II fatty acid biosynthesis pathway (PfFAS-II) has been found to be essential for complete liver-stage development and has been regarded as a potential antimalarial target for the development of drugs for malaria prophylaxis and liver-stage eradication. In this paper, new coumarin-based triclosan analogues are reported and their biological profile is explored in terms of inhibitory potency against enzymes of the PfFAS-II pathway. Among the tested compounds, 7 and 8 showed the highest inhibitory potency against Pf enoyl-ACP-reductase (PfFabI), followed by 15 and 3. Finally, we determined the crystal structures of compounds 7 and 11 in complex with PfFabI to identify their mode of binding and to confirm outcomes of docking simulations.

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Isotopic and trace element compositions of Miocene and Pliocene phosphatic brachiopods (Lingulidae and Discinidae) from southern North Sea, the Central Paratethys and the Atlantic coast of Europe were investigated in order to trace past environmental conditions and marine connections between the northern boreal and the southern subtropical-tropical marine basins. The North Sea genus Glottidia yielded low epsilon(Nd) and high delta O-18(PO4) values through the Mio-Pliocene indicating cold habitat temperature where the local seawater was dominated by the Atlantic Ocean. In contrast, the Middle Miocene Lingulidae and Discinidae of the Paratethys inhabited warm subtropical seawater with the possible influence of the Indian Ocean via the Mediterranean, as supported by their average epsilon(Nd) value of -8.3. The combined geochemical data support a thermal and marine separation of the Paratethys from the North Sea with no direct connection or major exchange of water from the Miocene onwards. The temperature in the Paratethys was very similar to that inferred from brachiopods from the Middle Miocene of western France, but the seawater epsilon(Nd) value here is identical to that of contemporaneous Atlantic Ocean. A Late Miocene lingulid brachiopod from southern Portugal has a high delta O-18(PO4), similar to the specimens investigated from the North Sea, reflecting either a deep water habitat or formation after the onset of major global cooling that resulted in an increased delta O-18 value of seawater. The epsilon(Nd) value of -8.4 for this site is compatible with an influence of Mediterranean outflow. (C) 2012 Elsevier B.V. All rights reserved.

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The objective of this work was to evaluate the production of flour using by-products (cephalothorax) obtained from the shrimp (Litopenaeus vannamei) industry, and to perform a sensory analysis of shrimp flour-based products. Physicochemical and microbiological analyses on fresh cephalothorax and on manufactured flour were performed, as well as the determination of cholesterol content of this flour, and the sensorial evaluation of soup and pastry made with this flour. By the microbiological analyses, no pathogenic microorganism was detected in the samples. Physicochemical analyses of flour showed high levels of protein (50.05%) and minerals (20.97%). Shrimp cephalothorax flour showed high levels of cholesterol. The sensory evaluation indicated a good acceptance of the products, with satisfactory acceptability index (81% for soup, and 83% for pastry), which indicates that shrimp cephalothorax in the form of flour has a potential for developing new products.

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Follicular Th (T(FH)) cells have emerged as a new Th subset providing help to B cells and supporting their differentiation into long-lived plasma cells or memory B cells. Their differentiation had not yet been investigated following neonatal immunization, which elicits delayed and limited germinal center (GC) responses. We demonstrate that neonatal immunization induces CXCR5(high)PD-1(high) CD4(+) T(FH) cells that exhibit T(FH) features (including Batf, Bcl6, c-Maf, ICOS, and IL-21 expression) and are able to migrate into the GCs. However, neonatal T(FH) cells fail to expand and to acquire a full-blown GC T(FH) phenotype, as reflected by a higher ratio of GC T(FH)/non-GC CD4(+) T cells in immunized adults than neonates (3.8 × 10(-3) versus 2.2 × 10(-3), p = 0.01). Following the adoptive transfer of naive adult OT-II CD4(+) T cells, OT-II T(FH) cells expand in the vaccine-draining lymph nodes of immunized adult but not infant recipients, whereas naive 2-wk-old CD4(+) OT-II cells failed to expand in adult hosts, reflecting the influence of both environmental and T cell-intrinsic factors. Postponing immunization to later in life increases the number of T(FH) cells in a stepwise manner, in direct correlation with the numbers of GC B cells and plasma cells elicited. Remarkably, adjuvantation with CpG oligonucleotides markedly increased GC T(FH) and GC B cell neonatal responses, up to adult levels. To our knowledge, this is the first demonstration that the T(FH) cell development limits early life GC responses and that adjuvants/delivery systems supporting T(FH) differentiation may restore adultlike early life GC B cell responses.

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Tutkielmantavoitteena oli luoda ohjeistus toimittajan valinnasta ja suorituskyvyn arvioinnista case - yrityksen, Exel Oyj:n, käyttöön. Ohjeistuksen tarkoituksena oli ollalähtökohtana toimittajan valinta- ja suoristuskyvyn arviointiprosessien kehittämisessä. Tutkielma keskittyy esittelemään toimittajan valintakriteereitä ja toimittajan suorituskyvyn arviointikriteereitä. Kriteerit valittiin ja analysoitiin teorian ja empirian avulla ja kriteereistä tehtiin selkeät listaukset. Näitä listoja käytettiin avuksi pohdittaessa uusia valintakriteereitä ja suorituskyvyn arviointikriteereitä, joita case -yritys voi jatkossa käyttää. Tutkielmassa käytiin läpi myös toimittajan valintaprosessi jaapuvälineitä ja mittareita toimittajan arviointiin liittyen. Empiirisen aineiston keruu toteutettiin haastattelemalla hankintapäällikköä sekä keräämällä tietoavuosikertomuksesta ja yrityksen internet sivuilta. Tutkielman tuloksena saatiinlistauksia kriteereistä, joita yritys voi hyödyntää jatkossa sekä listaukset kriteereistä, jotka valittiin alustavasti yrityksen käyttöön.

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Tutkimus koostuu neljästä artikkelista, jotka käsittelevät suomalaisten pienten ja keskisuurten teollisuusyritysten (PKT-yritysten) innovatiivisuutta, sen attribuutteja (ominaispiirteitä) sekä indikaattoreita. Tutkimuksessa tarkastellaan sekä kirjallisuudessa esitettyjä että PKT-johtajien ja PKT-yritystenkehityshankkeiden rahoituspäätöksiin osallistuvien yritystutkijoiden haastatteluissa esittämiä innovatiivisuuden määritelmiä. Innovatiivisuusindikaattoreista tarkastellaan PKT-yritysten kehittämishankkeille sovellettavia rahoitus- ja arviointikriteerejä sekä yritysten ulkopuolisten rahoittajien että PKT-johtajien näkökulmasta. Erityistä huomiota kohdistetaan sovellettuihin laadullisiin ja ei-numeerisiin innovatiivisuuden arviointikriteereihin. Sekä kirjallisuudessa että kymmenen yritystutkijan ja kuuden esimerkkiyrityksen johtajan haastatteluissa innovaation uutuus yhdistetään innovatiivisuuteen. Muita tärkeitä innovatiivisuuteen liitettyjä ominaisuuksia olivat markkinat, muista yrityksistä erottuminen ja yksilöiden luovuus. Ihmisläheiset ja yksilöihin liittyvät näkökulmat korostuvat yritystutkijoiden ja PKT-johtajien innovatiivisuuden määritelmissä, kun taas kirjallisuudessa annetaan enemmän painoa ympäristölle, tuotteille ja markkinoille. Yritystutkijat pitivät yritykseen ja sen johtajaan liittyviä tekijöitä tärkeinä rahoitettavien kehittämishankkeiden panosten arviointikriteereinä. Tuotteiden kaupallinen menestys oli rahoittajan kannalta tärkein tulostekijä. Tarkastelluissa esimerkkiyrityksissä kehityshankkeista päättäminen ja hankkeiden arviointi on toisaalta intuitiivista ja saattaa olla tiedostamatontakin, koska yritysten kehittämistoiminta on vähäistä. Pienyritysten johtajat korostavat arvioinnissa rahallisiamittareita, vaikka sekä numeerisia että laadullisia kriteereitä sovelletaan. Todennäköisin syy tälle on pienyritysten rajalliset taloudelliset voimavarat. Toinen mahdollinen syy rahoituksellisten tekijöiden painottamiseen on, että tämän päivän ihannejohtaja ymmärretään analyyttiseksi ja mm.rahavirtoja valvovaksi. Kuitenkin innovatiiviset yritysjohtajat pitävät innovaatioiden luomista yhtenä elämän hauskoista puolista. Innovatiiviset esimerkkiyritykset ovat tulevaisuuteen ja kasvuun suuntautuneita strategisella tasolla. Operationaalisella tasolla ne tuottavat keksintöjä ja innovaatioita. Patentteja tarkastelluilla yrityksillä on kuitenkin vähän. Sekä innovatiiviset että vähemmän innovatiiviset esimerkkiyritykset ovat voimakkaasti asiakassuuntautuneita ja erikoistuneita tiettyihin tuotteisiin ja asiakkaisiin. Asiakkaiden tarpeita tyydytetään kehittämällä niitä vastaavia tuotteita. Tästä johtuu, että valtaosa yritysten kehittämistoiminnasta kohdistuu tuotteisiin tai tuotantoon.

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Given the climatic changes around the world and the growing outdoor sports participation, existing guidelines and recommendations for exercising in naturally challenging environments such as heat, cold or altitude, exhibit potential shortcomings. Continuous efforts from sport sciences and exercise physiology communities aim at minimizing the risks of environmental-related illnesses during outdoor sports practices. Despite this, the use of simple weather indices does not permit an accurate estimation of the likelihood of facing thermal illnesses. This provides a critical foundation to modify available human comfort modeling and to integrate bio-meteorological data in order to improve the current guidelines. Although it requires further refinement, there is no doubt that standardizing the recently developed Universal Thermal Climate Index approach and its application in the field of sport sciences and exercise physiology may help to improve the appropriateness of the current guidelines for outdoor, recreational and competitive sports participation. This review first summarizes the main environmental-related risk factors that are susceptible to increase with recent climate changes when exercising outside and offers recommendations to combat them appropriately. Secondly, we briefly address the recent development of thermal stress models to assess the thermal comfort and physiological responses when practicing outdoor activities in challenging environments.

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Cirrhosis is the final stage of most of chronic liver diseases, and is almost invariably complicated by portal hypertension, which is the most important cause of morbidity and mortality in these patients. This review will focus on the non-invasive methods currently used in clinical practice for diagnosing liver cirrhosis and portal hypertension. The first-line techniques include physical examination, laboratory parameters, transient elastography and Doppler-US. More sophisticated imaging methods which are less commonly employed are CT scan and MRI, and new technologies which are currently under evaluation are MR elastography and acoustic radiation force imaging (ARFI). Even if none of them can replace the invasive measurement of hepatic venous pressure gradient and the endoscopic screening of gastroesophageal varices, they notably facilitate the clinical management of patients with cirrhosis and portal hypertension, and provide valuable prognostic information.

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This work presents new, efficient Markov chain Monte Carlo (MCMC) simulation methods for statistical analysis in various modelling applications. When using MCMC methods, the model is simulated repeatedly to explore the probability distribution describing the uncertainties in model parameters and predictions. In adaptive MCMC methods based on the Metropolis-Hastings algorithm, the proposal distribution needed by the algorithm learns from the target distribution as the simulation proceeds. Adaptive MCMC methods have been subject of intensive research lately, as they open a way for essentially easier use of the methodology. The lack of user-friendly computer programs has been a main obstacle for wider acceptance of the methods. This work provides two new adaptive MCMC methods: DRAM and AARJ. The DRAM method has been built especially to work in high dimensional and non-linear problems. The AARJ method is an extension to DRAM for model selection problems, where the mathematical formulation of the model is uncertain and we want simultaneously to fit several different models to the same observations. The methods were developed while keeping in mind the needs of modelling applications typical in environmental sciences. The development work has been pursued while working with several application projects. The applications presented in this work are: a winter time oxygen concentration model for Lake Tuusulanjärvi and adaptive control of the aerator; a nutrition model for Lake Pyhäjärvi and lake management planning; validation of the algorithms of the GOMOS ozone remote sensing instrument on board the Envisat satellite of European Space Agency and the study of the effects of aerosol model selection on the GOMOS algorithm.

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AIMS AND OBJECTIVES: To evaluate the reliability and the factor structure of the Readiness for Hospital Discharge Scale - French version. BACKGROUND: The patient's perspective is essential when assessing risk for adverse events at hospital discharge. Developed in the USA, the Readiness for Hospital Discharge Scale is the only instrument that measures an individual's self-perception of readiness before leaving the hospital. A French version of the Readiness for Hospital Discharge Scale was developed and validated. DESIGN: Cross-sectional study. METHODS: A convenience sample of 265 older inpatients from four medical units was selected. The translation and cultural adaptation of the scale involved experts in gerontology and the French language and included back translation. The items were semantically evaluated and pretested in 10 older inpatients. The scale's psychometric properties were internally validated by using confirmatory and exploratory factor analyses. Reliability was assessed by examining the internal consistency of its items. RESULTS: Goodness-of-fit indices of the confirmatory factor analyses were not adequate, but reliability was acceptable (Cronbach's α = 0·80). Exploratory factor analysis of the French version provided results close to those described for the English version, with three similar subscales (physical and emotional readiness, coping with medical treatment and personal care), whereas the initially described Expected Support subscale was not identified in the French version. CONCLUSION: The Readiness for Hospital Discharge Scale - French version appears to be partially consistent with its original English version, but requires additional adaptation to fully take into account the Swiss context and culture to achieve its original aim. RELEVANCE TO CLINICAL PRACTICE: Assessing patient readiness for hospital discharge before leaving hospital could help nurses to improve the discharge planning process and achieve better patient preparedness and care coordination.