To see the other types of publications on this topic, follow the link: Continuum de soin.
Dissertations / Theses on the topic 'Continuum de soin'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Continuum de soin.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Luong, Nguyen Liêm Binh. "Modélisation et analyse en coût-efficacité des stratégies de prévention, de dépistage et de traitement de l'infection par le VIH à Ndhiwa, Kenya." Electronic Thesis or Diss., Université Paris Cité, 2021. http://www.theses.fr/2021UNIP5233.
Full textAbstract:
Médecin Sans Frontière (MSF) intervient depuis les années 1980 à Ndhiwa, un sous-comté du Sud-Ouest du Kenya, où sévit une épidémie généralisée de VIH, avec une prévalence à 24% et une incidence à 2,2/100 personnes année (PA). Conformément aux objectifs de l’ONUSIDA 90-90-90, puis 95-95-95, MSF a décidé de mettre en place différentes interventions pour diminuer l’incidence de l’infection par le VIH. Dans un premier temps, nous avons développé un modèle mathématique de la transmission et de l’histoire naturelle de l’infection par le VIH à Ndhiwa afin d’étudier l’efficacité et le coût efficacité de trois niveaux d’interventions sur le continuum de soin. Nous avons ainsi estimé qu’en maintenant l’offre de soins à son niveau actuel, sans intervention, l’incidence de l’infection par le VIH diminuerait à 1,51/100 PA en 2032, tandis que seules les interventions de rétention et la combinaison de toutes les stratégies faisaient baisser l’incidence respectivement à 1,03/100 PA et 0,75/100 PA. Comparé au standard de soins, la stratégie de rétention avait un rapport incrémental de coût-efficacité de 130€/année de vie gagnée (AVG) tandis que La combinaison des interventions atteint un ICER de 370€/AVG. Dans un deuxième temps, nous avons modélisé l’efficacité d’une intervention qui améliorerait le continuum de soin de 90-90-90 à 95-95-95, comparée à une intervention qui implémenterait une prophylaxie pré-exposition (PrEP) sur une population à haut risque avec un taux de couverture de 10%. Nous estimons que dans une épidémie généralisée où le continuum de soin atteint 90-90-90, l’amélioration du continuum de soin à 95-95-95 est plus efficace que la PrEP pour diminuer l’incidence de l’infection par le VIH En conclusion, les résultats de notre travail soulignent les effets synergiques e très coût-efficace d’interventions multimodales sur le continuum de soin, et leur rôle important aussi important que la PrEP pour diminuer l’incidence de l’infection par le VIH<br>Médecin Sans Frontière (MSF) have been working since the early 1980’s on HIV care delivery in Ndhiwa, a rural sub-county in Southwest Kenya. This area suffers from a generalized HIV epidemic, with 24% prevalence and 2.2/100 person years (PY) incidence. In line with the UNAIDS 90-90-90 and 95-95-95 targets, MSF has implemented interventions to decrease HIV incidence. In the first part of this work, we have developped a mathematical model of HIV natural history and transmission in Ndhiwa to evaluate the effectiveness and cost-effectiveness of three different interventions on HIV continuum of care. We estimated than current standard of care would decrease HIV incidence to 1.51/100 PY in 2032, whereas only retention intervention and combined interventions would further decrease HIV incidence to 1.03/100 PY and 0,75/100 PY, respectively. Compared to standard of care, retention to care intervention has an incremental cost-effectiveness ratio (ICER) of 130€/years of live saved (YLS) whereas combined intervention has an ICER of 370€/YLS. In the second part, we modeled the effectiveness of the improvement of continuum of care from 90-90-90 to 95-95-95, compared with a Pre-exposure Prophylaxis (PrEP) intervention with 10% coverage in high-risk group. We found that in the context of generalized epidemic where continuum of care reach 90-90-90, an improvement to 95-95-95 would be more effective than PrEP to decrease incidence. To conclude, combined interventions on HIV continuum of care have synergic effects and are very cost-effective. We also underlined the importance of maintaining a high level continuum of care to decrease HIV incidence, which is as important as PrEP to fight the HIV pandemic
2
Park, Soojin. "Modelling soil-landform continuum on a three-dimensional hillslope." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670238.
Full text
3
Williams, Jonathan Simon. "Fate and transport of lignin in the soil-water continuum." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2668.
Full textAbstract:
Vascular plants comprise 20-30% lignin, constituting a considerable organic input to soils. Lignin is not necessarily preserved in soils, but the fate of its decomposition products in the wider environment is not well understood. Therefore, the overarching hypothesis tested herein was that a significant proportion of lignin is solubilised and lost from soils by transport in water. Solid phase extraction was used to extract lignin phenols from dissolved organic matter (DOM) from water outlets adjacent to major land use types (grazed grassland, deciduous woodland, and moorland) and compared to the lignin phenols from representative vegetation types, animal dungs and soils from each land use type. The phenols were identified and quantified using thermally assisted hydrolysis and methylation using tetramethylammonium hydroxide. Leachates from lysimeters treated with four vegetation types (grass, buttercup, ash, and oak) were sampled in a 22 month chronosequence, showing that some of the dominant phenols detected in the vegetation were also dominant in the respective DOM. A proportional relationship between increasing temperature and loss of representative lignin phenols in DOM was observed. Comparison of the dominant phenols in vegetation, soil and water sampled from field sites suggested specific lignin phenols could be used as biomarkers for different land uses. The concentrations of organic carbon-normalised total lignin phenols in the soils were similar to those in water, indicating that a considerable proportion of lignin in soils is lost via leaching. There was no significant difference in losses of lignin phenols between each land use type. Application of different rates of dissolved lignin to lysimeters indicated that the amount of water added was a dominant driver of transport through soil over 16 days, and that molecular structure also influenced transport rates of individual phenols. The impact of this research is that climate change (increased precipitation and warming) may significantly affect the loss of lignin by increased solubilisation and leaching from soils.
4
Busato, Laura. "Non-invasive monitoring and numerical modeling of the Soil-Plant continuum." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3425720.
Full textAbstract:
The Earth’s critical zone (ECZ) is the near-surface domain that regulates the availability of most life-sustaining resources. Among all the subdomains of the ECZ, a crucial role is played by the Soil-Plant continuum (SP), as it is a major performer of the exchanges of mass and energy between soil and plants (and then atmosphere). However, despite its importance and its strong interconnection with human activity, the characterization of this subdomain is still in an early stage, mainly because of the lack of spatial and temporal information regarding the occurring processes. To overcome this issue, we present the combination of geophysical measurements and hydrological modeling in the framework of a hydrogeophysical approach, with the aim of characterizing the active root zone, i.e. the portion of the root system involved in the water uptake. In fact, the water uptake is performed by root hair, the microscopic cell outgrowths whose location is difficult (if not impossible) also after the removal of the root system from the soil. Nevertheless, determining its position is fundamental not only for merely scientific purposes, but most of all for practical applications, as it affects the performing of precision irrigation. Therefore, in this work I propose the identification of the active root zone on the basis of its main effect, i.e. the reduction of soil water content over time. This is achieved by means of 3-D small-scale electrical resistivity tomography (ERT) carried out combining superficial and borehole electrodes. We monitored the processes occur-ring in the root zone of three orange trees located in south-eastern Sicily. These trees are drip irrigated according to different deficit irrigation techniques to improve the exploitation of the water resource, while the plants’ transpiration is monitored thanks to sap flow and eddy covariance measurements. More in detail, in the first case study ERT measurements before and after the cut of the tree are compared, while in the second case study the ERT monitoring is focused on two orange trees drip irrigated with different treatments (i.e. full irrigation and partial root drying). The datasets thus obtained provide interesting insights into the root system activity, given their abundance of information regarding both atmospheric and underground phenomena (i.e. transpiration and root water uptake, respectively). In particular, the ERT time-lapse approach well highlights the portions subject to a decrease in water content, which can be related to the water uptake put in place by the plants. Nevertheless, the interpretation of the resistivity patterns, although combined with agronomic information, can be rather intricate. A proper hydrological modeling provides a solution to this problem, even if choosing the most suitable approach requires a specific mathematical analysis. To do this, we developed a synthetic case study with two identical hydrological models, one of which describing also the activity of an orange tree. These models resemble the real datasets provided by the ERT measurements, without all the uncertainties introduced by the geophysical acquisition and the model calibration. The location of the active root zone is reconstructed from the combination of these two models by means of Taylor series expansion, with particular reference to the effects of the approximation thus introduced. The final aim is to evaluate the proposed numerical procedure for a future application on one of real case study presented in this work.<br>La Earth's critical zone (ECZ) rappresenta la porzione più esterna del pianeta Terra ed è sede di numerosi processi che regolano la disponibilità della maggior parte delle sostanze necessarie alla vita. Tra i vari sottodomini in cui essa può essere suddivisa, il continuum Suolo-Pianta (SP) svolge un ruolo cruciale, in quanto è uno dei maggiori regolatori degli scambi di massa ed energia tra suolo e piante (e quindi atmosfera). Nonostante la forte interconnessione con l'attività umana, la caratterizzazione del SP è ancora in una fase embrionale, principalmente legata alla mancanza di informazioni sia spaziali che temporali riguardo ai processi che lo caratterizzano. In questo lavoro presentiamo quindi una combinazione di tomografia di resistività elettrica (ERT) e modellazione idrologica secondo l'approccio idrogeofisico, con l'obiettivo di caratterizzare la "active root zone", ossia la porzione del sistema radicale coinvolta nel processo di assorbimento di acqua dal suolo. Più nel dettaglio, questo processo è messo in atto dai peli radicali, delle microscopiche estroflessioni la cui localizzazione è difficile (se non impossibile) anche in seguito alla rimozione del sistema radicale dal suolo. Ciononostante, la sua localizzazione è fondamentale soprattutto da un punto di vista agronomico, poiché necessaria per una corretta applicazione delle tecniche di irrigazione di precisione. In questo lavoro presento quindi due casi studio in cui l'active root zone è identificata sulla base del suo effetto principale, ossia la diminuzione di contenuto idrico del suolo. I casi studio presentati comprendono tre alberi d’arancio situati nel sud-est della Sicilia ed irrigati mediante diverse tecniche di microirrigazione (nota anche come "irrigazione a goccia"). In particolare, nel primo caso studio sono comparate misure ERT acquisite prima e dopo il taglio della pianta, mentre nel secondo caso studio il monitoraggio ERT è focalizzato su due aranci irrigati con diverse tecniche (piena irrigazione e disseccamento parziale delle radici). Il monitoraggio ERT dei processi in atto è effettuato sulla piccola scala (cioè sulla singola pianta) grazie alla combinazione di elettrodi superficiali ed in pozzo, permettendo così una acquisizione ed una rappresentazione tridimensionale del dato geofisico. Parallelamente ha luogo anche il monitoraggio agronomico, grazie al quale la traspirazione è determinata mediante misure di sap flow e di eddy covariance. I dati così ottenuti forniscono molte informazioni rispetto ai diversi processi in atto, sia atmosferici (traspirazione), che nel sottosuolo (assorbimento di acqua dal suolo). In particolare, il monitoraggio ERT in time-lapse è in grado di mostrare quali porzioni del dominio investigato siano soggette ad una diminuzione del contenuto idrico, la quale può essere collegata all’attività radicale. Nonostante la quantità e qualità dei dati a disposizione, l'interpretazione dei risultati (specialmente in termini quantitativi) risulta comunque piuttosto complessa. Una soluzione può essere fornita da un'appropriata modellazione idrologica, sebbene la scelta dell’approccio migliore richieda una specifica analisi matematica. Sotto quest’ottica abbiamo sviluppato un caso sintetico costituito da due modelli idrologici identici, dove uno quali descrive anche l'attività di una pianta d'arancio. Questi modelli hanno lo scopo di ricreare dei dataset riconducibili all'output delle misure ERT, senza però tutte le incertezze introdotte dall’acquisizione geofisica e dalla calibrazione del modello. La ricostruzione della "active root zone" è quindi ottenuta dalla combinazione di questi due modelli mediante l'espansione in serie di Taylor, con particolare attenzione alle approssimazioni così introdotte. L'obiettivo finale è quello di valutare questa procedura numerica per una futura applicazione ad uno dei casi studio reali presentati in questo lavoro.
5
Sadeghi, Tehrani Faraz. "An investigation of continuous compaction control systems." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 435 p, 2009. http://proquest.umi.com/pqdweb?did=1889078521&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full text
6
Rahgozar, Mandana Seyed. "Estimation of evapotranspiration using continuous soil moisture measurement." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001812.
Full text
7
Davison, L. R. "Continuous loading consolidation tests on soils." Thesis, University of the West of England, Bristol, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234804.
Full text
8
Vanella, Daniela. "Monitoring and modeling fluxes transfer processes in soil-plant-atmosphere continuum across scales." Doctoral thesis, Università di Catania, 2017. http://hdl.handle.net/10761/4084.
Full textAbstract:
Alle interazioni tra le diverse componenti del sistema suolo-pianta-atmosfera (SPA) è attribuito un ruolo critico nel ciclo idrologico e della biosfera terrestre.
La comunità scientifica specializzata è sempre più consapevole della necessità di portare avanti studi a carattere interdisciplinare per la comprensione delle interazioni funzionali tra le risorse naturali ed i relativi problemi di sostenibilità del sistema SPA.
All interno di tali studi interdisciplinari, l analisi delle interazioni suolo-radice risulta rilevante anche per la gestione ottimale dell'irrigazione, in particolare nelle zone caratterizzate da scarsa disponibilità idrica, come le aree mediterranee. A tal fine nasce l esigenza di valutare, ad alta risoluzione sia spaziale che temporale, le dinamiche idrologiche del sistema SPA, sino alla scala dell apparato radicale.
Il contributo della tesi di dottorato consiste nell applicazione di tecniche di monitoraggio avanzate e minimamente invasive, per valutare gli scambi di massa ed energia all'interno del sistema SPA.
L aspetto innovativo del lavoro di tesi consiste nell integrazione di tecniche geofisiche con misure micrometeorologiche e dati di traspirazione, al fine di interpretare alcuni dei principali processi di trasferimento di flussi nel sistema SPA (evapotraspirazione ed assorbimento radicale) in ambiente semi-arido.
Tale approccio, è stato applicato a due Casi studio con l obiettivo di monitorare le complesse interazioni del sistema suolo-pianta, con particolare riferimento al processo di assorbimento radicale di alberi di agrume.
Nel primo Caso studio, la tecnica della tomografia di resistività elettrica (ERT) tridimensionale è stata integrata con dati di traspirazione, misure micrometeorologiche e modellistica idrologica al fine di delineare la porzione di suolo non satura interessata dalle radici attive di un aranceto adulto.
Nel secondo Caso studio, il monitoraggio ERT è stato integrato con misure di traspirazione al fine di delineare i pattern di RWU di alberi di arancio irrigati in regime di deficit.
I risultati del lavoro di tesi dimostrano l abilità della tecnica di monitoraggio geofisico ERT nello spiegare le dinamiche idriche del suolo e la risposta fisiologica della pianta, in termini di attività delle radici nel processo di uptake, contribuendo, in tal senso, a migliorare la conoscenza dei processi di assorbimento radicale.
9
Cottier, Jean-Bernard. "Soigner son travail pour prendre soin des autres : l’expérience d’un espace de parole entre soignants : une occasion de professionnalisation du rôle relationnel ?" Thesis, Nantes, 2019. http://www.theses.fr/2019NANT2037.
Full textAbstract:
Cette recherche est issue d’une expérience qui s’est déroulée sur une période de cinq ans (2003-2008) dans un service de gastro-entérologie. L’auteur de cette thèse a éprouvé le besoin de solliciter quelques soignants ayant volontairement participé à un groupe de réflexion qui les réunissait régulièrement dans leur service ; ces instants leur permettaient d’évoquer leurs difficultés, leurs interrogations, leurs doutes, voire leurs souffrances. Bien des années plus tard, l’infirmier-doctorant qui a participé activement à cette initiative a voulu comprendre pourquoi cette expérience avait mobilisé certains soignants. Il importait de les rencontrer dix ans plus tard pour identifier avec le recul les bénéfices qu’ils avaient éventuellement retirés de ces temps d’éducation informelle. A la faveur des récits recueillis, une thèse s’est progressivement imposée : pour prendre soin des autres, le soignant n’a d’autres recours que de se raconter, entouré par ses pairs. C’est la figure du sujet apprenant qui émerge à travers ces récits d’apprentissage réalisés au sein d’un groupe. En faisant ces choix, ces professionnels accèdent aux quatre dimensions qui caractérisent le sujet : il est capable, sensible, situé socialement et en mesure de conduire une réflexion. C’est à la faveur de l’émergence de cette figure énigmatique d’un sujet apprenant au sein de ce groupe de réflexion que ces soignants construisent un rapport critique au savoir, se remettent en question et participent ainsi à un processus de développement professionnel et personnel tant pour eux-mêmes que pour les autres<br>This research is based on a five-year experience (2003-2008) in a gastroenterology department. The author of this thesis has felt the need to request some caregivers having voluntarily participated in a think tank which gathered them regularly in the department; these moments allowed them to express their hardships, their questioning, their doubts, even their suffering. Many years later, the nurse and PhD student who actively participated wanted to know why this experience had motivated some of the caregivers. It was important to meet them ten years later to identify with hindsight the benefits which they had possibly gained from these educational informal times. Thanks to the collected narratives, a hypothesis became obvious: to take care of others, the caregivers has no recourse but to talk, surrounded by his peers. This is the position of the learner which emerges through these learning narratives realized into group practice. By making their choice, these learners have access to four dimensions that characterize the subject : he is capable, sensitive, socially situated and able to lead a reflexion. By the emergence of this enigmatic learning subject within think tank, these caregivers make a criticism of their own knowledge, question themselves and so participate in a process of professional and personal self-growth both for themselves and others
10
Viscarra, Rossel Raphael A. "Development of a Proximal Soil Sensing System for the Continuous Management of Acid Soil." Thesis, The University of Sydney, 2001. http://hdl.handle.net/2123/674.
Full textAbstract:
The notion that agriculturally productive land may be treated as a relatively homogeneous resource at thewithin-field scale is not sound. This assumption and the subsequent uniform application of planting material,chemicals and/or tillage effort may result in zones within a field being under- or over-treated. Arising fromthese are problems associated with the inefficient use of input resources, economically significant yield losses,excessive energy costs, gaseous or percolatory release of chemicals into the environment, unacceptable long-term retention of chemicals and a less-than-optimal growing environment. The environmental impact of cropproduction systems is substantial. In this millennium, three important issues for scientists and agrariancommunities to address are the need to efficiently manage agricultural land for sustainable production, the maintenance of soil and water resources and the environmental quality of agricultural land.Precision agriculture (PA) aims to identify soil and crop attribute variability, and manage it in an accurate and timely manner for near-optimal crop production. Unlike conventional agricultural management where an averaged whole-field analytical result is employed for decision-making, management in PA is based on site-specific soil and crop information. That is, resource application and agronomic practices are matched with variation in soil attributes and crop requirements across a field or management unit. Conceptually PA makes economic and environmental sense, optimising gross margins and minimising the environmental impact of crop production systems. Although the economic justification for PA can be readily calculated, concepts such as environmental containment and the safety of agrochemicals in soil are more difficult to estimate. However,it may be argued that if PA lessens the overall agrochemical load in agricultural and non-agricultural environments, then its value as a management system for agriculture increases substantially.Management using PA requires detailed information of the spatial and temporal variation in crop yield components, weeds, soil-borne pests and attributes of physical, chemical and biological soil fertility. However,detailed descriptions of fine scale variation in soil properties have always been difficult and costly to perform.Sensing and scanning technologies need to be developed to more efficiently and economically obtain accurate information on the extent and variability of soil attributes that affect crop growth and yield. The primary aim of this work is to conduct research towards the development of an 'on-the-go' proximal soil pH and lime requirement sensing system for real-time continuous management of acid soil. It is divided into four sections.Section one consists of two chapters; the first describes global and historical events that converged into the development of precision agriculture, while chapter two provides reviews of statistical and geostatistical techniques that are used for the quantification of soil spatial variability and of topics that are integral to the concept of precision agriculture. The review then focuses on technologies that are used for the complete enumeration of soil, namely remote and proximal sensing.Section two comprises three chapters that deal with sampling and mapping methods. Chapter three provides a general description of the environment in the experimental field. It provides descriptions of the field site,topography, soil condition at the time of sampling, and the spatial variability of surface soil chemical properties. It also described the methods of sampling and laboratory analyses. Chapter four discusses some of the implications of soil sampling on analytical results and presents a review that quantifies the accuracy,precision and cost of current laboratory techniques. The chapter also presents analytical results that show theloss of information in kriged maps of lime requirement resulting from decreases in sample size. The messageof chapter four is that the evolution of precision agriculture calls for the development of 'on-the-go' proximal soil sensing systems to characterise soil spatial variability rapidly, economically, accurately and in a timely manner. Chapter five suggests that for sparsely sampled data the choice of spatial modelling and mapping techniques is important for reliable results and accurate representations of field soil variability. It assesses a number of geostatistical methodologies that may be used to model and map non-stationary soil data, in this instance soil pH and organic carbon. Intrinsic random functions of order k produced the most accurate and parsimonious predictions of all of the methods tested.Section three consists of two chapters whose theme pertains to sustainable and efficient management of acid agricultural soil. Chapter six discusses soil acidity, its causes, consequences and current management practices.It also reports the global extent of soil acidity and that which occurs in Australia. The chapter closes by proposing a real-time continuous management system for the management of acid soil. Chapter seven reports results from experiments conducted towards the development of an 'on-the-go' proximal soil pH and lime requirement sensing system that may be used for the real-time continuous management of acid soil. Assessment of four potentiometric sensors showed that the pH Ion Sensitive Field Effect Transistor (ISFET)was most suitable for inclusion in the proposed sensing system. It is accurate and precise, drift and hysteresis are low, and most importantly it's response time is small. A design for the analytical system was presented based on flow injection analysis (FIA) and sequential injection analysis (SIA) concepts. Two different modes of operation were described. Kinetic experiments were conducted to characterise soil:0.01M CaCl2 pH(pHCaCl2) and soil:lime requirement buffer (pH buffer) reactions. Modelling of the pH buffer reactions described their sequential, biphasic nature. A statistical methodology was devised to predict pH buffer measurements using only initial reaction measurements at 0.5s, 1s, 2s and 3s measurements. The accuracy of the technique was 0.1pH buffer units and the bias was low. Finally, the chapter describes a framework for the development of a prototype soil pH and lime requirement sensing system and the creative design of the system.The final section relates to the management of acid soil by liming. Chapter eight describes the development of empirical deterministic models for rapid predictions of lime requirement. The response surface models are based on soil:lime incubations, pH buffer measurements and the selection of target pH values. These models are more accurate and more practical than more conventional techniques, and may be more suitably incorporated into the spatial decision-support system of the proposed real-time continuous system for the management of acid soil. Chapter nine presents a glasshouse liming experiment that was used to authenticate the lime requirement model derived in the previous chapter. It also presents soil property interactions and soil-plant relationships in acid and ameliorated soil, to compare the effects of no lime applications, single-rate and variable-rate liming. Chapter X presents a methodology for modelling crop yields in the presence of uncertainty. The local uncertainty about soil properties and the uncertainty about model parameters were accounted for by using indicator kriging and Latin Hypercube Sampling for the propagation of uncertainties through two regression functions; a yield response function and one that equates resultant pH after the application of lime. Under the assumptions and constraints of the analysis, single-rate liming was found to be the best management option.
11
Viscarra, Rossel Raphael A. "Development of a Proximal Soil Sensing System for the Continuous Management of Acid Soil." University of Sydney. Agricultural Chemistry and Soil Science, 2001. http://hdl.handle.net/2123/674.
Full textAbstract:
The notion that agriculturally productive land may be treated as a relatively homogeneous resource at thewithin-field scale is not sound. This assumption and the subsequent uniform application of planting material,chemicals and/or tillage effort may result in zones within a field being under- or over-treated. Arising fromthese are problems associated with the inefficient use of input resources, economically significant yield losses,excessive energy costs, gaseous or percolatory release of chemicals into the environment, unacceptable long-term retention of chemicals and a less-than-optimal growing environment. The environmental impact of cropproduction systems is substantial. In this millennium, three important issues for scientists and agrariancommunities to address are the need to efficiently manage agricultural land for sustainable production, themaintenance of soil and water resources and the environmental quality of agricultural land.Precision agriculture (PA) aims to identify soil and crop attribute variability, and manage it in an accurate andtimely manner for near-optimal crop production. Unlike conventional agricultural management where anaveraged whole-field analytical result is employed for decision-making, management in PA is based on site-specific soil and crop information. That is, resource application and agronomic practices are matched withvariation in soil attributes and crop requirements across a field or management unit. Conceptually PA makeseconomic and environmental sense, optimising gross margins and minimising the environmental impact ofcrop production systems. Although the economic justification for PA can be readily calculated, concepts suchas environmental containment and the safety of agrochemicals in soil are more difficult to estimate. However,it may be argued that if PA lessens the overall agrochemical load in agricultural and non-agriculturalenvironments, then its value as a management system for agriculture increases substantially.Management using PA requires detailed information of the spatial and temporal variation in crop yieldcomponents, weeds, soil-borne pests and attributes of physical, chemical and biological soil fertility. However,detailed descriptions of fine scale variation in soil properties have always been difficult and costly to perform.Sensing and scanning technologies need to be developed to more efficiently and economically obtain accurateinformation on the extent and variability of soil attributes that affect crop growth and yield. The primary aimof this work is to conduct research towards the development of an �on-the-go� proximal soil pH and limerequirement sensing system for real-time continuous management of acid soil. It is divided into four sections.Section one consists of two chapters; the first describes global and historical events that converged into thedevelopment of precision agriculture, while chapter two provides reviews of statistical and geostatisticaltechniques that are used for the quantification of soil spatial variability and of topics that are integral to theconcept of precision agriculture. The review then focuses on technologies that are used for the completeenumeration of soil, namely remote and proximal sensing.Section two comprises three chapters that deal with sampling and mapping methods. Chapter three provides ageneral description of the environment in the experimental field. It provides descriptions of the field site,topography, soil condition at the time of sampling, and the spatial variability of surface soil chemicalproperties. It also described the methods of sampling and laboratory analyses. Chapter four discusses some ofthe implications of soil sampling on analytical results and presents a review that quantifies the accuracy,precision and cost of current laboratory techniques. The chapter also presents analytical results that show theloss of information in kriged maps of lime requirement resulting from decreases in sample size. The messageof chapter four is that the evolution of precision agriculture calls for the development of �on-the-go� proximalsoil sensing systems to characterise soil spatial variability rapidly, economically, accurately and in a timelymanner. Chapter five suggests that for sparsely sampled data the choice of spatial modelling and mappingtechniques is important for reliable results and accurate representations of field soil variability. It assesses anumber of geostatistical methodologies that may be used to model and map non-stationary soil data, in thisinstance soil pH and organic carbon. Intrinsic random functions of order k produced the most accurate andparsimonious predictions of all of the methods tested.Section three consists of two chapters whose theme pertains to sustainable and efficient management of acidagricultural soil. Chapter six discusses soil acidity, its causes, consequences and current management practices.It also reports the global extent of soil acidity and that which occurs in Australia. The chapter closes byproposing a real-time continuous management system for the management of acid soil. Chapter seven reportsresults from experiments conducted towards the development of an �on-the-go� proximal soil pH and limerequirement sensing system that may be used for the real-time continuous management of acid soil.Assessment of four potentiometric sensors showed that the pH Ion Sensitive Field Effect Transistor (ISFET)was most suitable for inclusion in the proposed sensing system. It is accurate and precise, drift and hysteresisare low, and most importantly it�s response time is small. A design for the analytical system was presentedbased on flow injection analysis (FIA) and sequential injection analysis (SIA) concepts. Two different modesof operation were described. Kinetic experiments were conducted to characterise soil:0.01M CaCl2 pH(pHCaCl2) and soil:lime requirement buffer (pHbuffer) reactions. Modelling of the pHbuffer reactions describedtheir sequential, biphasic nature. A statistical methodology was devised to predict pHbuffer measurements usingonly initial reaction measurements at 0.5s, 1s, 2s and 3s measurements. The accuracy of the technique was 0.1pHbuffer units and the bias was low. Finally, the chapter describes a framework for the development of aprototype soil pH and lime requirement sensing system and the creative design of the system.The final section relates to the management of acid soil by liming. Chapter eight describes the development ofempirical deterministic models for rapid predictions of lime requirement. The response surface models arebased on soil:lime incubations, pHbuffer measurements and the selection of target pH values. These models aremore accurate and more practical than more conventional techniques, and may be more suitably incorporatedinto the spatial decision-support system of the proposed real-time continuous system for the management ofacid soil. Chapter nine presents a glasshouse liming experiment that was used to authenticate the limerequirement model derived in the previous chapter. It also presents soil property interactions and soil-plantrelationships in acid and ameliorated soil, to compare the effects of no lime applications, single-rate andvariable-rate liming. Chapter X presents a methodology for modelling crop yields in the presence ofuncertainty. The local uncertainty about soil properties and the uncertainty about model parameters wereaccounted for by using indicator kriging and Latin Hypercube Sampling for the propagation of uncertaintiesthrough two regression functions; a yield response function and one that equates resultant pH after theapplication of lime. Under the assumptions and constraints of the analysis, single-rate liming was found to bethe best management option.
12
Rappaport, Bruce D. "Availability and distribution of heavy metals from sewage sludge in the plant-soil continuum." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71177.
Full textAbstract:
An investigation was conducted using in situ lysimeters (1.5 m x 2.3 m) to determine Cd, Cu, Ni, and Zn availabilities for barley (Hordeum vulgare L.) and corn (Zea mays L.) grown on four sludge-amended soils. These lysimeters were constructed in Acredale silt loam (Typic Ochraqualf), Bojac loamy sand (Typic Hapludult), Davidson clay loam (Rhodie Paleudult), and Groseclose silt loam (Typic Hapludult) soils. An aerobically digested sewage sludge from a sewage system with major industrial inputs was applied at rates of 0, 42, and 84 dry Mg ha-t to the lysimeters in the poorly-drained Acredale soil. Rates of 0, 42, 84, 126, 168, and 210 dry Mg ha-1 were applied to the lysimeters in the well-drained Bojac, Davidson, and Groseclose soils.
Tissue metal concentrations were determined in 1984 and 1985 for a three crop rotation, which consisted of corn, barley, and corn on the Acredale soil. Increases in sludge-borne Ni and Zn led to increases in Ni and Zn concentrations in corn earleaf, corn grain, and barley silage. Copper concentration was increased in barley silage but not in corn grain and stover. On this poorly-drained soil, metal movement did not occur below the Ap horizon even when Cu was applied in excess of USEPA guidelines. Although there were increases in metal levels, all four metals were within the range considered normal for corn and barley growth.
Soil, corn, and barley plants were sampled in 1984 and 1985 to determine Cd, Cr, Cu, Ni, and Zn availabilities for crops grown on the sludge-amended Bojac, Davidson, and Groseclose soils. Levels of DTPA-extractable Cd, Cu, Ni, and Zn in the Ap horizon of these soils increased linearly with sludge rate. Corn grain and stover yields were not decreased on the Bojac, Davidson, and Groseclose soils when 4.5, 5105, 760, 43.0, 135, and 620 kg ha-1 of Cd, Cr, Cu, Ni, Pb, and Zn were added as a sludge-amendment. Copper and Zn applied in excess of 480 and 60 kg ha- 1 of USEPA guidelines, respectively on the Bojac, Davidson, and Groseclose soils were not phytotoxic to corn plants in 1984. Corn and barley tissue sampled for three consecutive seasons had Cr concentrations <2.8 mg kg-1.<br>Ph. D.
13
Eude, Yohann. "Développement d'un outil de simulation numérique des écoulements réactifs sur maillage auto-adaptatif et son application à un moteur à détonation continue." Phd thesis, Université d'Orléans, 2011. http://tel.archives-ouvertes.fr/tel-00702569.
Full textAbstract:
Dans le but d'améliorer le rendement des propulseurs aérospatiaux, on s'intéresse à l'utilisation de ladétonation dans le cycle moteur. Cette thèse porte sur le développement et l'utilisation d'un codepour la compréhension du fonctionnement d'un moteur à détonation continue (CDWE). Le 1erchapitre place le cadre de l'étude, et positionne le CDWE par rapport à différents concepts demoteurs à détonation. Un état des lieux des simulations numériques concernant le fonctionnementd'un CDWE est établi afin de justifier l'approche numérique à utiliser. Cette approche numérique estdétaillée dans le 2e chapitre. Les équations d'Euler, les modèles thermochimiques, ainsi que lesschémas cinétiques utilisés dans cette étude y sont présentés. Le 3e chapitre décrit les méthodesnumériques implémentées dans le code. Le schéma WENO d'ordre 5 est utilisé pour l'évaluation desflux numériques. L'avancement temporel est assuré par le schéma semi-implicite d'ordre 2 ASIRK2Cou explicite d'ordre 3 RK3. Le 4e chapitre est consacré à la technique de raffinement adaptatif demaillage (AMR) et à la bibliothèque choisie. Le code est testé dans le 5e chapitre sur différents cas etappliqué à la simulation d'une onde de détonation afin de préparer les simulations présentées dans ledernier chapitre. Le 6e chapitre présente les résultats des simulations d'un CDWE. La structure 2Dd'une onde de détonation continue est présentée et comparée avec la structure 3D. L'influence durayon de courbure du canal et l'effet d'une injection par une fente sur la structure de l'écoulementsont étudiés.
14
Göttlicher, Sabine. "On the tree-root-soil-continuum - temporal and spatial coupling of the belowground carbon flux /." Umeå : Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200743.pdf.
Full text
15
Peukert, Sabine. "Understanding the effects of different grassland management practices on the soil-to-water transfer continuum." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/16687.
Full textAbstract:
One of the major challenges for agriculture today is to manage soil properties and their spatial distribution to optimize productivity and minimize environmental impacts, such as diffuse pollution. To identify best management practices, the effects of different agricultural management practices on pollutant sources, mobilization, transfer and delivery to water bodies need to be understood. Grasslands managed for dairy and meat production, despite being widespread, have received less research attention than other agricultural land uses. Therefore, this thesis studies the effects of different grassland management practices on soil properties and their spatial distribution and the mobilization and delivery of multiple diffuse pollutants. As a grassland case study, monitoring for this thesis was conducted across three fields (6.5 – 7.5 ha) on the North Wyke Farm Platform, a grassland experimental farm in the UK. First, the effects of permanent grassland management (permanent for at least 6 years, but different grassland management > 6 years ago) were characterized as a baseline, followed by quantifying the short-term effects of ploughing and reseeding of permanent grassland fields. Throughout those management periods, i) a range of soil physical (bulk density [BD]) and chemical (soil organic matter [SOM], total N [TN], total phosphorus [TP], total carbon [TC]) soil properties and their spatial distribution were sampled and analysed by geostatistics, and ii) hydrological characteristics and multiple pollutant fluxes (suspended sediment [SS] and the macronutrients: total oxidized nitrogen-N [TONN], total phosphorus [TP], and total carbon [TC]) were monitored at high temporal resolution (monitoring up to every 15 minutes). The permanent grassland fields (or areas within fields) can be considered to be functioning differently. Past management legacy (more than 6 years ago) has affected soil properties and their distribution with subsequent effects on sediment and macronutrient delivery from the fields to surface waters. Overall, permanent grasslands were found to contribute significantly to agricultural diffuse pollution. The estimated erosion and macronutrient losses were similar to or exceeded the losses reported for other grasslands, mixed land use and even arable sites, and sediment and TP concentrations exceeded those recommended by EU / UK water quality guidelines. Ploughing and reseeding did not homogenize spatial variation and did not override past management effects. Long-term management differences affected soil properties and altered soil processes, so that the fields subsequently responded differently to ploughing and reseeding. All nutrient concentrations were significantly reduced in the older grassland field (no ploughing for 20 years), but not in the younger grassland field (no ploughing for 6 years). Ploughing and reseeding significantly accelerated the losses of sediment and macronutrients and sediment, TP and TONN exceedance frequencies of EU / UK water quality guidelines increased. Additionally, ploughing and reseeding caused a shift in the relative importance of nutrients, by increasing the relative importance of N. Such large sediment and nutrient losses from intensively managed grasslands should be acknowledged in land management guidelines and advice for future compliance with surface water quality standards. The between-field and within-field variation highlights the importance of baseline characterization and paired catchment studies. The long-term effects of management still acting on soil properties and subsequently water quality indicates how long it may take to see soil and water quality improvements after implementing mitigation measures. Therefore, long-term management history always has to be included when interpreting soil and water quality data.
16
Ahlman, Björn. "Coarse-Graining Fields in Particle-Based Soil Models." Thesis, Umeå universitet, Institutionen för fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-173534.
Full textAbstract:
In soil, where trees and crops grow, heavy vehicles shear and compact the soil, leading to reduced plant growth and diminished nutrient recycling. Computer simulations offer the possibility to improve the understanding of these undesired phenomena. In this thesis, soils were modelled as large collections of contacting spherical particles using the Discrete Element Method (DEM) and the physics engine AGX Dynamics, and these entities were analyzed. In the first part of the thesis, soils, which were considered to be continua, were subjected to various controlled deformations and fields for quantities such as stress and strain were visualized using coarse graining (CG). These fields were then compared against analytical solutions. The main goal of the thesis was to evaluate the usefulness, accuracy, and precision of this plotting technique when applied to DEM-soils. The general behaviour of most fields agreed well with analytical or expected behaviour. Moreover, the fields presented valuable information about phenomena in the soils. Relative errors varied from 1.2 to 27 %. The errors were believed to arise chiefly from non-uniform displacement (due to the inherent granularity in the technique), and unintended uneven particle distribution. The most prominent drawback with the technique was found to be the unreliability of the plots near the boundaries. This is significant, since the behaviour of a soil at the surface where it is in contact with e.g. a vehicle tyre is of interest. In the second part of the thesis, a vehicle traversed a soil and fields were visualized using the same technique. Following a limited analysis, it was found that the stress in the soil can be crudely approximated as the stress in a linear elastic solid.
17
Scott, James D. "Availability and distribution of nitrogen and phosphorus from sewage sludge in the plant-soil-water continuum." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/43892.
Full textAbstract:
Research was conducted in 1984 and 1985 to determine N and P availabilities for barley (Hordeum vulgare L.) and com ( Zea mays L.) grown on four sludge-amended soils. Tests were conducted on the Acredale silt loam (Typic Ochraquall), Bojac loamy sand (Typic Hapludult), Davidson clay loam (Rhodic Paleudult), and Groseclose silt loam (Typic Hapludult) soils. An aerobically·digested sewage sludge from a sewage treatment plant with major industrial irrputs was applied at rates of 0, 42, and 84 dry Mg ha' 1 on the poorly-drained Acredale soil. Rates of 0, 42, 84, 126, 168, and 210 dry Mg ha'1 were applied on the well-drained Bojac, Davidson, and Groseclose soils. The 210 dry Mg haâ 1 sludge rate supplied 3300 and 6600 kg of N and P haâ 1, respectively. A 14-day anaerobic N incubation study indicated that mirreralization varied from approximately nine to four percent of sludge N from the 42 to 210 Mg haâ 1 application rates, respectively. Sludge application increased N uptake (rz = 0.98** to 0.99**) by the 1984 com grown on the three well-drained soils. Nitrogen balance data indicated that quantities of unrecovered N ranged from six to 21 percent where sludge was applied.<br>Master of Science
18
DeJong, Jason Theodore. "Investigation of particulate-continuum interface mechanisms and their assessment through a multi-friction sleeve penetrometer attachment." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/21536.
Full text
19
Manunta, Paolo. "Modelling strategies of the soil plant atmosphere continuum in water limited environments and elevated atmospheric CO¦2." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0010/NQ59998.pdf.
Full text
20
von, Rein Isabell. "Plant and soil microbial responses to drought stress in different ecosystems: the importance of maintaining the continuum." Doctoral thesis, Humboldt-Universität zu Berlin, 2017. http://dx.doi.org/10.18452/18064.
Full textAbstract:
Der Klimawandel bedroht Ökosysteme auf der ganzen Welt. Besonders der Anstieg in Länge, Intensität und Häufigkeit von Dürren kann bedeutenden Einfluss auf den globalen Kohlenstoffkreislauf haben. Die Frage, ob Pflanzen und Mikroorganismen anfällig gegenüber ökologischem Stress wie Dürren sind, wurde bereits in vielen Studien für verschiedene Ökosysteme und mit verschiedenen Ansätzen untersucht, aber Analysen von Dürreauswirkungen, die ober- und unterirdische Interaktionen von Pflanzen und Mikroorganismen mit einbeziehen, sind eher selten. Deshalb wird in der vorliegenden Studie die Frage erörtert, wie Trockenheit und/oder Hitze die Interaktionen von Pflanzen und Mikroorganismen in Bezug auf ihre Kohlenstoff-Verbindung beeinflussen. Dies dient zur Bestimmung der Stärke der Pflanze-Mikroorganismen-Kohlenstoff-Verbindung, wenn das Ökosystem an seine Grenzen gebracht wird.
Der Fokus liegt deshalb auf durch Trockenstress und Hitze hervorgerufenen Veränderungen in der ober-unterirdischen Kohlenstoff-Dynamik in zwei vom Klimawandel bedrohten Ökosystemen. Es wurde untersucht, wie extreme Klimaereignisse, deren Häufigkeit in Zukunft weiter ansteigen soll, die Kohlenstoff-Verbindung zwischen Pflanzen und Mikroorganismen beeinflusst und wie mikrobielle Gemeinschaften unter diesen Umständen reagieren, um die Resistenz und Reaktionsmechanismen von Ökosystemen im zukünftigen Klimawandel besser vorhersagen zu können.
In Kapitel 4 wurde ein Buchenwaldunterholz-Ökosystem untersucht. Buchenwaldmonolithen wurden einem extremen Klimaereignis (Trockenheit und/oder Hitze) ausgesetzt. Die Stärke der Pflanze-Mikroorganismen-Kohlenstoff-Verbindung und Veränderungen in der mikrobiellen Gemeinschaftsstruktur und -aktivität wurden mithilfe von stabilen 13C Isotopenmethoden und Ansätzen auf molekularer Basis, wie 16S rRNA- und Phospholipid-Analysen, bestimmt. In Kapitel 5 wurde ein kleines aquatisches Ökosystems untersucht. Zwei emerse aquatische Makrophyten, Phragmites australis und Typha latifolia, wurden in einem Mesokosmos-Experiment mit Sediment aus einem Soll einer einmonatigen Dürre ausgesetzt. Mithilfe einer 13CO2 Pulsmarkierung, sowie PLFA- und nicht-strukturbildenden Kohlenhydrat-Analysen wurde Kohlenstoff von den Blättern in die Wurzeln bis ins Sediment verfolgt, wo er teilweise in mikrobielle Phospholipide eingebaut wird.
Diese Studie hat gezeigt, dass die zwei untersuchten Ökosysteme Trockenstress und Hitze relativ gut widerstehen können, zumindest kurzfristig, und dass das Kohlenstoff-Kontinuum, beziehungsweise die Verbindung zwischen ober- und unterirdischen Gemeinschaften, auch unter starkem Stress intakt bleibt. Zusammenfassend scheint es, dass Ökosysteme stark von einem funktionierenden Pflanze-Boden/Sediment-Mikroorganismen Kohlenstoff-Kontinuum abhängen und versuchen, es auch unter starkem Stress zu erhalten, was möglicherweise dazu beiträgt, dem Anstieg von extremen Dürreperioden aufgrund des Klimawandels besser zu widerstehen.<br>Climate change is threatening ecosystems around the world. Especially the increase in duration, intensity, and frequency of droughts can have a considerable impact on the global carbon cycle. The question whether plants and microbes are susceptible to environmental stress like drought has been assessed in many studies for different ecosystem types and by using numerous approaches, but research on drought effects that includes above- and belowground interactions is rather scarce. Therefore, the present study assesses the question of how drought and/or heat influence the interactions of plants and microbes, especially the carbon coupling, in order to determine the strength of plant-microbe carbon linkages when an ecosystem is pushed to its limits.
The focus of this study thus lies on changes in aboveground-belowground carbon dynamics and the subsequent effects on the soil microbial community under drought and/or heat stress in two climate-threatened ecosystems. It was evaluated how extreme climate events, that are predicted to be more frequent in the near future, affect the carbon coupling between plants and microorganisms and how microbial communities respond under these circumstances, in order to be able to better predict ecosystem resistance and response mechanisms under future climate change.
In chapter 4 a beech forest understory ecosystem was investigated. An extreme climate event (drought and/or heat) was imposed on beech forest monoliths and the strength of the plant-microbe carbon linkages and changes in the microbial community structure and activity were determined by using stable 13C isotope techniques and molecular-based approaches like 16S rRNA and microbial phospholipid-derived fatty acid (PLFA) analysis. In chapter 5 a small aquatic ecosystems was investigated. Two emergent aquatic macrophytes, Phragmites australis and Typha latifolia, were grown on kettle hole sediment and then exposed to a month-long summer drought in a mesocosm experiment. By conducting a 13CO2 pulse labeling as well as PLFA and non-structural carbohydrate analyses, the fate of carbon was traced from the plant leaves to the roots and into the sediment, where some of the recently assimilated carbon is incorporated into microbial PLFAs.
Overall, this study showed that the two investigated ecosystems can endure environmental stress like heat and drought relatively well, at least in the short-term, and that the carbon continuum, or the linkage between above- and belowground communities, remained intact even under severe stress. In conclusion, it seems that ecosystems strongly depend on and try to maintain a functional plant-soil/sediment microorganism carbon continuum under drought, which might help to withstand the increase in extreme drought events under future climate change.
21
Berg, Karin. "Simulations of groundwater levels and soil water content : Development of a conceptual hydrological model with a continous soil profile." Thesis, Linköping University, Department of Thematic Studies, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1910.
Full textAbstract:
<p>Transport of chemical substances through a catchment depend to a large extent on the water content of the soil through which they are transported. When the groundwater level rise and fall, redox conditions change in the soil and the transport of substances is affected. </p><p>The aim of this study is to develop a hydrological model which is able to simulate soil water content at different depths and groundwater level in a soil profile. A new type of conceptual model is developed, which uses a continous represenation of the soil and soil water from the soil surface down to the bedrock. The model is intended to be applied on small catchments at a later stage. </p><p>The results show that the simulation of groundwater levels was greatly improved compared to previous results. Simulation of soil water content at selected depths is not yet satisfactory. The runoff simulation was accurate at one of the sites but did not work as well at the other. At one of the sites it was also possible to combine good simulations of runoff and groundwater levels but at the other it was only possible to obtain acceptable simulations of either runoff or groundwater. </p><p>It is suggested that model performance could be improved by letting the porosity decrease and the soil water content increase non-linearly with depth. Calculations of evaporation from soil and runoff also need to be modified.</p>
22
Martinez, Alejandro. "Multi-scale studies of particulate-continuum interface systems under axial and torsional loading conditions." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54423.
Full textAbstract:
The study of the shear behavior of particulate (soil) – continuum (man-made material) interfaces has received significant attention during the last three decades. The historical belief that the particulate – continuum interface represents the weak link in most geotechnical systems has been shown to be incorrect for many situations. Namely, prescribing properties of the continuum material, such as its surface roughness and hardness, can result in interface strengths that are equal to the contacting soil mass internal shear strength. This research expands the engineering implications of these findings by studying the response of interface systems in different loading conditions. Specifically, the axial and torsional shear modes are studied in detail. Throughout this thesis it is shown that taking an engineering approach to design the loading conditions induced to the interface system can result in interface strengths that exceed the previously considered limiting shear strength of the contacting soil.
Fundamental experimental and numerical studies on specimens of different types of sand subjected to torsional and axial interface shear highlighted the inherent differences of these processes. Specifically, micro-scale soil deformation measurements showed that torsional shear induces larger soil deformations as compared to axial shear, as well as complex volume-change tendencies consisting of dilation and contraction in the primary and secondary shear zones. Studies on the global response of torsional and axial shear tests showed that they are affected differently by soil properties such as particle angularity and roughness. This difference in global behavior highlights the benefits of making systems that transfer load to the contacting soil in different manners available for use in geotechnical engineering. Discrete Element Modeling (DEM) simulations allowed for internal information of the specimens to be studied, such as their fabric and shear-induced loading conditions. These findings allowed for the development of links between the measured micro-scale behavior and the observed global-scale response.
The understanding of the behavior of torsional and axial interfaces has allowed provides a framework for the development of enhanced geotechnical systems and applications. The global response of torsional shear found to induce larger cyclic contractive tendencies within the contacting soil mass. Therefore, this shear mode is more desirable than the conventional axial shear for the study of phenomena that depend on soil contractive behavior, such as liquefaction. A study on the influence of surface roughness form revealed that surfaces with periodic profiles of protruding elements that prevent clogging are capable of mobilizing interface friction angles that are 20 to 60% larger than the soil friction angle. These findings have direct implications in engineering design since their implementation can result in more resilient and sustainable geotechnical systems.
23
Bakker, Eleanor. "The impact of plant growth and potassium uptake on clay minerals in soil." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAU012/document.
Full textAbstract:
Le potassium est un nutriment essentiel à la croissance et au développement des plantes. Les minéraux argileux dans les sols représentent un important réservoir de K disponible pour les plantes. L'extraction de K fixé à partir de l'espace interfoliaire des minéraux micacés 2:1 peut entraîner une augmentation de la distance feuillet à feuillet qui peut être mesurée par diffraction des rayons X . Des échantillons de l'expérience Morrow Plots continue avec du maïs (C) ou du maïs-avoine-foin (R), provenant de sous-parcelles fertilisées (F) et non fertilisées (U) pour les années 1904, 1957, 1980, 1997 et 2013-2014, ont été soumis au fractionnement granulométrique séquentiel pour obtenir la fraction limoneuse (50-2 um) et les sous-fractions argileuses (2-0,2, 0,2-0,05 et <0,05 um). Les résultats granulométriques montrent une hétérogénéité significative malgré la petite taille de la MP, et un gain de sous-fraction < 0,05 um avec le temps. La modélisation des diagrammes de diffraction des rayons X a été effectuée pour obtenir une identification concluante de l'assemblage de minéraux argileux et évaluer l'impact de 110 ans d'agriculture continue et de différentes pratiques agronomiques. Un assemblage complexe de minéraux argileux a été identifié avec jusqu'à onze contributions différentes nécessaires pour reproduire les données expérimentales de sous-fractions de moins de 2 um, y compris jusqu'à six couches mixtes d'illite-smectite-chlorite. L'analyse de phase quantitative pour toutes les sous-parcelles et toutes les années, a montré que l'assemblage minéral du MP est similaire entre les différentes sous-parcelles, quel que soit le traitement agronomique. Aucune preuve significative d'altération ou de transformation des phases minérales argileuses n'a été observée au fil du temps. La nature dioctaédrique des minéraux argileux de la MP désavantage l'extraction du K et donc la dissolution est le mécanisme privilégié pour l'absorption du K et la perte de sous-fractions 2-0,2 et 0,2-0,05 um est attribuée à ce processus<br>Potassium is an essential nutrient for plant growth and development. Clay minerals in soils represent an important reservoir of plant-available K. Extraction of fixed K from the interlayer space of micaceous 2:1 minerals can lead to an increase in the layer-to-layer distance which can be measured by X-ray diffraction. Samples from the Morrow Plots continuous corn (C) and corn-oats-hay (R) experiment, from fertilised (F) and non-fertilised (U) subplots for the years 1904, 1957, 1980, 1997 and 2013-2014 were subjected to sequential size-fractionation to obtain the silt fraction (50-2 um) and clay-sized subfractions (2-0.2, 0.2-0,05 and <0.05 um). Granulometric results show siginificant heterogeneity despite the small size of the MP, and a gain in <0.05 um subfraction with time. Full-profile fitting of X-ray diffraction patterns was performed to obtain conclusive identification of the clay mineral assemblage and assess the impact of 110-years of continuous agriculture and different agronomic practices. A complex clay mineral assemblage was identified with up to eleven different contributions necessary to reproduce the experimental data of <2 um subfractions, including up to six illite-smectite-chlorite mixed-layers. Quantitative phase analysis for all subplots and years showed that the mineral assemblage of the MP is similar between different subplots, regardless of agronomic treatment. No significant evidence of alteration or transformation of clay mineral phases was observed over time. The dioctahedral nature of the clay minerals of the MP disfavours K-extraction and thus dissolution is the favoured mechanism for K-uptake and the loss of 2-0.2 and 0.2-0.05 um subfractions is attributed to this process
24
Moreno-Urquiza, Magdalena 1967. "Intelligent data acquisition system for continuous measurements of soil moisture in the field." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278271.
Full textAbstract:
A data acquisition system to collect soil moisture readings at 60 field locations was developed. The system predicted a resistance value from a measured counts per time. An error was associated with the measured counts and time, however, this error was minimized by increasing the time for resistance measurement. The effect of temperature was minimized by an automatic calibration of the system before collecting readings. The Watermark electrical resistance moisture sensor was used to sense water content. The system, including eight sensors, was tested in the field. The data collected was difficult to explain. An evaluation of the Watermark sensors indicated a large variation from sensor to sensor, and also indicated a marked influence of soil texture on sensor resistance.
25
Spargo, John T. "Continuous No-till Management: Implications for Soil Quality, Carbon Sequestration, and Nitrogen Conservation." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26166.
Full textAbstract:
No-till management for agronomic crop production is recognized as an effective practice to regain a portion of soil organic matter lost following decades of cultivation. Increasing soil organic matter sequesters C, conserves organic N and concomitantly improves soil quality. Objectives of this research were to: i) quantify C sequestration rate and N conservation with duration of continuous no-till; ii) measure C stratification with continuous no-till as an indicator of soil quality; and iii) evaluate the Illinois soil N test (ISNT) for its value to predict fertilizer N needs of corn in Virginia.
Objectives i and ii were achieved by collecting soil samples from 63 production fields in the Virginia Coastal Plain that were managed using continuous no-till from 0 to 14 yrs. No-till management resulted in sequestration of 0.308 ± 0.280 Mg C ha-1 yr-1 and conservation of 22.2 ± 21.2 kg N ha-1 yr-1 (0-15 cm). The C stratification ratio (0-2.5 cm: 7.5-15 cm) increased with increasing duration of continuous no-till (0.133 ± 0.056 yr-1) due to the accumulation of organic matter at the soil surface indicating improved soil quality with continuous no-till management.
Objective iii was addressed by conducting 29 on-farm fertilizer N response trials in major corn producing areas of Virginia with the duration of continuous no-till management ranging from 0 to 25 yrs. The ISNT values were significantly related to yield without fertilizer N (r2 = 0.57; p<0.001) and relative yield (r2 = 0.64; p<0.0001). We also found that the ISNT extracted a relatively consistent percentage of total soil N (16.3 ± 0.73 %) suggesting it is a poor indicator of labile N. Total soil N values did almost as well as the ISNT in predicting yield without fertilizer N (r2 = 0.53; p = 0.0002), and equally well predicting relative yield (r2 = 0.64; p<0.0001). Results do not suggest the ISNT is useful for measuring mineralizalbe N or improving fertilizer N recommendations in Virginia cropping systems.<br>Ph. D.
26
Marceau, Mélanie. "Développement et évaluation d'une activité de formation continue adaptée aux infirmières et infirmiers oeuvrant en traumatologie." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/4003.
Full textAbstract:
L'écart entre les compétences attendues des infirmières et infirmiers dans le service des urgences et la formation ne cesse de s'agrandir. De plus, la clientèle polytraumatisée, complexe et variée, nécessite une approche structurée, basée sur des standards de pratique, connue par toute l'équipe infirmière, médicale et d'inhalothérapie. Pour pallier à ces difficultés, la formation continue est essentielle et contribue, entre autres, à augmenter la qualité des soins et à diminuer la mortalité et la morbidité auprès des personnes polytraumatisées. Peu d'activités de formation continue existent pour les infirmières et infirmiers du service des urgences oeuvrant auprès de la clientèle polytraumatisée. Les formations continues reconnues sont coûteuses, difficilement accessibles et elles ne reposent pas sur une évaluation des besoins du personnel infirmier ciblé. Objectifs. Cette étude avait pour but de développer et d'évaluer une activité de formation continue pour les infirmières et infirmiers du service des urgences oeuvrant en traumatologie en (1) identifiant leurs besoins spécifiques de formation continue, (2) évaluant leurs connaissances générales avant, après et trois mois suivant une activité de formation continue, (3) évaluant les connaissances procédurales avant, après et trois mois suivant une activité de formation continue et (4) évaluant la satisfaction des participantes et participants concernant la réponse à leurs besoins de formation. Méthodologie. Cette étude s'appuie sur le modèle conceptuel de compétence de Le Boterf (2006) et utilise un devis qualitatif évaluatif de 4e génération selon Guba et Lincoln (1989) dans lequel se sont ajoutées des données quantitatives. Les données quantitatives ont été recueillies par le biais d'un questionnaire sociodémographique et de questionnaires d'évaluation des connaissances alors que, pour les données qualitatives, des entrevues de groupe focalisé ainsi qu'un questionnaire d'évaluation de la satisfaction ont été nécessaires. Résultats. Les résultats recueillis auprès de 33 participantes et participants illustrent le lien entre l'évaluation des besoins et la construction d'une activité de formation continue par et pour les infirmières et infirmiers du service des urgences d'un centre hospitalier universitaire oeuvrant auprès de personnes polytraumatisées. Cette activité de formation continue, construite avec la collaboration des ressources du milieu, s'est avérée peu coûteuse pour les personnes participantes, accessible et basée sur les besoins du personnel infirmier. On remarque une augmentation des connaissances générales et procédurales concernant les soins donnés aux personnes polytraumatisées qui se sont maintenues dans le temps. Conclusion. L'approche participative innovatrice utilisée dans cette étude a contribué au sentiment d'implication ressenti par le personnel infirmier tout au long du processus de construction et de mise en oeuvre d'activités de formation continue.
27
Kuruppuarachchi, Don Stanley Premalal. "Productivity of irrigated potatoes in warm tropical lowlands influenced by water transport in the soil-plant-atmosphere continuum." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302821.
Full text
28
CHAMPION, PASCALE. "L'enregistrmeent cardiaque continu : son interet dans un service de medecine interne." Angers, 1994. http://www.theses.fr/1994ANGE1010.
Full text
29
Tremblay, Pierre-Luc. "Développement et évaluation d’une activité de formation continue pour les infirmières et infirmiers œuvrant en soins critiques pédiatriques concernant le processus de don d’organes." Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8959.
Full textAbstract:
Introduction. Le don d’organes chez la clientèle pédiatrique demeure un domaine peu étudié. Malgré que la population pédiatrique représente moins de 10 % de l’ensemble des donneurs au Québec, il demeure que des donneurs potentiels ne sont pas identifiés et le taux de refus des familles demeure élevé. Les infirmières sont les seules professionnelles constamment au chevet des patients et, selon leurs dires, elles manquent de connaissances sur ce sujet. La formation des infirmières pourrait amener une meilleure connaissance du processus de don d’organes et un meilleur accompagnement des familles dans ce contexte. Par ailleurs, les formations sont peu nombreuses, coûteuses et ne sont pas basées sur une évaluation des besoins de formation identifiés par les infirmières elles-mêmes. Objectifs. Cette recherche avait pour but de développer et d’évaluer une activité de formation continue concernant le don d’organes pédiatrique et destinée aux infirmières de ce domaine de soins. Les objectifs étaient : 1) de décrire les composantes essentielles d’une formation continue concernant le processus de don d’organes, 2) valider ces composantes essentielles auprès des détenteurs d’enjeux, 3) construire une activité de formation basée sur ces composantes, 4) d’évaluer les connaissances et les intérêts avant et après l’activité de formation continue, et 5) d’évaluer la satisfaction des participants après la formation. Méthodologie. Le modèle de Michaud, Dionne et Beaulieu (2007) a servi de cadre conceptuel de la compétence dans cette étude et s’inspire du devis qualitatif évaluatif de 4e génération de Guba et Lincoln (1989). D’abord, pour l’évaluation des besoins, des données quantitatives issues d’un questionnaire préliminaire en ligne, suivi d’un forum de discussion virtuel, furent utilisés. Une activité de formation continue modulaire en ligne fut créée, combinée à un pré-test et post-test. À ce dernier était greffé un questionnaire de satisfaction des participants. Résultats. Au départ, 51 participants contribuèrent à l’établissement des besoins de formation. Pour la formation, 13 infirmières l’ont suivie et ont montré une amélioration de leurs connaissances, notamment au niveau du soutien aux familles et sur le concept de mort cérébrale. Le sentiment augmenté d’auto-efficacité, associé aux ressources internes furent partagés par les participants lors du questionnaire de satisfaction.
30
Boyer, Eric. "Continuous auditory feedback for sensorimotor learning." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066165/document.
Full textAbstract:
Notre système sensorimoteur a développé une relation particulière entre nos actions et le retour sonore qui en découle. Les systèmes de captation gestuelle et les technologies audio permettent de manipuler ce retour sonore par la sonification interactive du mouvement. Nous explorons dans divers cadres expérimentaux la contribution de la sonification à l'apprentissage moteur dans les systèmes interactifs. Tout d'abord, nous montrons que le système auditif intègre des indices acoustiques issus du mouvement pour le contrôle moteur. Des représentations de l'espace émergent de ces indices et sont transformées en commandes motrices. Le cas d'un objet virtuel sonore nous apprend que ces représentations audiomotrices influencent les stratégies d'exploration et permettent des cas de substitution sensorielle par le son. Ensuite, nous mesurons qu'un retour sonore continu permet d'améliorer significativement la performance à une tâche de poursuite. La sonification de l'erreur et des paramètres de la tâche aident à la performance mais montrent des effets différents sur l'apprentissage. Nous observons également que la sonification du mouvement de l'utilisateur augmente l'énergie contenue dans le geste et prévient la dépendance au retour sonore. Enfin, nous présentons le concept de tâche sonore dans lequel la cible est présentée et s'exprime sous forme de paramètres sonores à reproduire. Les résultats montrent qu'une adaptation motrice peut être provoquée par des indices acoustiques seuls. Ce travail permet de dégager des principes importants du design de l'interaction geste-son, et présente des applications originales comme des scénarios interactifs pour la rééducation<br>Our sensorimotor system has developed a specific relationship between our actions and their sonic outcomes, which it interprets as auditory feedback. The development of motion sensing and audio technologies allows emphasizing this relationship through interactive sonification of movement. We propose several experimental frameworks (visual, non-visual, tangible, virtual) to assess the contribution of sonification to sensorimotor control and learning in interactive systems. First, we show that the auditory system integrates dynamic auditory cues for online motor control, either from head or hand movements. Auditory representations of space and of the scene can be built from audio features and transformed into motor commands. The framework of a virtual sonic object illustrates that auditory-motor representations can shape exploratory movement features and allow for sensory substitution. Second, we measure that continuous auditory feedback in a tracking task helps significantly the performance. Both error and task sonification can help performance but have different effects on learning. We also observe that sonification of user’s movement can increase the energy of produced motion and prevent feedback dependency. Finally, we present the concept of sound-oriented task, where the target is expressed as acoustic features to match. We show that motor adaptation can be driven by interactive audio cues only. In this work, we highlight important guidelines for sonification design in auditory-motor coupling research, as well as applications through original setups we developed, like perceptual and physical training, and playful gesture-sound interactive scenarios for rehabilitation
31
Tsang, Chiu Ming. "Life-time analysis of continuous beam bridges with integral abutments using rheological models." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/8609.
Full text
32
Diendere, Ella. "Issues cliniques des patients autochtones victimes d'un empoisonnement dans le continuum de soins : une étude de cohorte rétrospective multicentrique." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/70361.
Full textAbstract:
Introduction Les populations autochtones du Canada ont une incidence élevée d'empoisonnements, lesquels sont associés à une morbidité et mortalité élevées. Des soins sous-optimaux prodigués aux populations autochtones ont d’ailleurs été énoncés pour expliquer ce fardeau. Malgré ces constats alarmants, notre connaissance des soins d’urgence offerts à ces populations est très limitée. Notre étude se propose donc d’évaluer si des différences existent dans le continuum de soins des patients victimes d’empoisonnement, vivant en milieu rural dans la province de Québec au Canada, en fonction de l’origine ethnique. Méthodologie Nous avons réalisé une étude de cohorte rétrospective multicentrique à partir des données du Centre antipoison du Québec (CAPQ) entre 2016-2017. Les patients d’origine autochtone ont été comparés aux patients non-autochtone, tous vivant en région éloignée. Notre critère de jugement principal était la durée de prise en charge prodiguée par le CAPQ. Une méthode de régression linéaire généralisée a été utilisée pour évaluer les différences de durée de prise en charge entre les groupes. Une analyse différenciée selon le sexe a également été effectuée. Notre critère de jugement secondaire était la gravité des symptômes au terme du suivi. Résultats Parmi 362 patients (184 autochtones/178 non-autochtones), nous n’avons pas observé de différence dans le délai de prise en charge entre les groupes (GMR ajusté=1,09 [IC 95% 0,87 ; 1,38]). L’association n’était pas différente en fonction du sexe. Les symptômes au terme du suivi étaient légers à modérés pour la majorité des patients (78%). Un seul cas de décès a été enregistré dans chaque groupe. Le CAPQ a reçu très peu de références des Premières Nations dites ‘non-conventionnées’. Conclusion Nous n’avons pas observé de disparités de prise en charge chez les patients vivant en région éloignée. La perception de soins sous-optimaux offerts aux populations autochtones semble liée à l’éloignement géographique et non à l’origine ethnique.<br>Background Indigenous population have a high incidence of poisoning cases across Canada, which is associated with high morbidity and mortality. A suboptimal provision of health care was suggested to explain suchburden. Unfortunately, very little information is available to describe the specific presentations of poisoning cases in Indigenous populations. There fore, our study aims to assess whether differences exist in the continuum of care of poisoned patients living in rural regions in Quebec, Canada, according to their ethnic origin. Methods We conducted a multicenter retrospective cohort study using data from the Centre antipoison du Québec (CAPQ) between 2016 and 2017. Indigenous poisoned patients were compared to non Indigenous patients living in rural areas. Our main outcome was the duration of involvement by the CAPQ in case management, reflecting the time required to complete toxicological management. Generalized linear regression was used to evaluate differences in the duration of poison center involvement between the two populations. A sex-specific analysis was also conducted. Our secondary outcome was the symptom severity at the conclusion of management. Results Among 362 identified poisoned patients (184 Indigenous and 178 non-Indigenous), we observed no differences in the duration of case management between groups (GMR adjusted = 1.09; [95% CI 0.87;1.38]). Moreover, the sex-specific analysis showed that the association was not significant in either male or female groups. High proportion of patients, in both Indigenous and non-Indigenous groups,showing mild to moderate symptoms at follow-up (78%). One death was registered in each group. The CAPQ received very few calls from the non-conventioned First Nations during the study period. Interpretation We did not observe any difference on the duration in case management of cases between patients living in rural areas. Perceptions of suboptimal care provided to rural Indigenous population are likelyto be related to geographical remoteness rather than ethnicity.
33
REGNI, MARCO. "The Role of Soil-Structure Interaction in Interpretation of Vibration Measurements on Continuous Viaducts." Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263550.
Full textAbstract:
L’oggetto della tesi è lo studio dell’effetto dell'interazione terreno-struttura e della risposta di sito sul comportamento dinamico di viadotti continui a più campate, sviluppato sia sperimentalmente tramite misure di vibrazioni ambientali sia numericamente, tramite modelli raffinati agli elementi finiti.
A tal fine, sono state eseguite prove di vibrazione ambientale su un ponte multi-campata, fondato su pali in un deposito eluviale-colluviale, caratterizzato dinamicamente da indagini geofisiche. Le proprietà modali sperimentali sono state valutate mediante l'analisi modale operativa sui dati misurati e il ruolo dell'interazione terreno-struttura nell'interpretazione dei test è stato riscontrato mediante modelli agli elementi finiti caratterizzati da diversa accuratezza nella modellazione delle fondazioni e dell’interazione con il terreno. Le impedenze tra fondazioni e terreno sono state definite a partire dalla condizione locale del sito in corrispondenza di ciascuna pila. Il confronto tra i risultati sperimentali ottenuti dalle prove sul terreno e sull’impalcato consente di identificare sia il periodo predominante del sito che i periodi fondamentali della struttura. Inoltre, il confronto tra i risultati ottenuti dai diversi modelli numerici con la risposta dinamica del viadotto, consente l'identificazione del contributo di diversi aspetti di interazione tra terreno e struttura come l’interazione tra le pile, il problema della dissipazione per radiazione, l'ingombro della zattera e la variabilità della stratigrafia del suolo lungo la direzione longitudinale del viadotto.
Sono state eseguite alcune prove in corrispondenza di una pila del viadotto per identificare il contributo allo spostamento modale trasversale dovuto alla deformazione elastica delle pile e alla rotazione della fondazione.
In aggiunta, vengono presentati altri due casi studio di viadotti con caratteristiche diverse al precedente, allo scopo di ampliare lo studio dell’interazione terreno-struttura.<br>The scope of this thesis is to identify the significance of soil-structure interaction (SSI) and site response on the dynamic behaviour of continuous multi-span reinforced concrete viaducts, based on ambient vibration tests (AVTs) and numerical simulations with finite element models.
For this purpose, a long bridge located in Central Italy, founded on piles in eluvial-colluvial soil deposit was instrumented and AVTs together with geophysical investigations were performed. Experimental modal properties were evaluated by means of operational modal analysis on recorded data and the role of SSI in the interpretation of the tests was detected by means of finite element models characterised by different accuracy in addressing the interaction problem. In the SSI models the local site condition in correspondence with each bridge piers were considered in the definition of soil-foundations impedances. Comparison between the experimental results obtained from AVTs on the free-field and on the viaduct deck, permits the identification of both predominant period of the site and the fundamental periods of the structure. In addition, comparisons between results obtained from the different numerical models with the measured dynamic response of the viaduct, in terms of fundamental frequencies and mode shapes, allow the identification of the contribution of different SSI aspects such as the pile-soil-pile interaction, the radiation problem, the pile cap embedment as well as the variability of the soil stratigraphy along the longitudinal direction of the viaduct.
About the transverse behaviour, some tests were performed in correspondence with one pier, measuring accelerations of the foundation cap and the pier bent, to identify the contribution to the transverse modal displacement due to the elastic deflection of the pier and the foundation rocking.
In addition, other two viaducts, with different characteristics respect to the previous one, were presented, for extending the study of SSI.
34
Dallaire, Frédéric. "Création sonore et cinéma contemporain : la pensée et la pratique du mixage." Thèse, Paris 10, 2014. http://hdl.handle.net/1866/11587.
Full textAbstract:
Notre thèse décrit et analyse les conditions esthétiques, matérielles et idéelles qui rendent possibles les agencements sonores du cinéma contemporain. Au cours des 30 dernières années, le raffinement des outils de manipulation du son, l’importance grandissante du concepteur sonore et le nouvel espace de cohabitation des sons (favorisé par le Dolby et la diffusion multicanal) sont des facteurs qui ont transformé la création et l’écoute du son au cinéma. Ces transformations révèlent un nouveau paradigme : le mixage s’est graduellement imposé comme le geste perceptif et créateur qui rend compte de la sensibilité contemporaine. Notre thèse explore les effets de la pensée du mixage (qui procède par résonance, simultanéité, dosage et modulation) sur notre écoute et notre compréhension de l'expérience cinématographique. À l'aide de paroles de concepteurs sonores (Murch, Beaugrand, Thom, Allard…), de textes théoriques sur le son filmique (Cardinal, Chion, Campan), de documentaires sur des musiciens improvisateurs (Lussier, Glennie, Frith), de films de fiction à la dimension sonore affirmée (Denis, Van Sant), de textes philosophiques sur la perception (Leibniz, James, Straus, Szendy…), d'analyses du dispositif sonore cinématographique, notre thèse rend audibles des tensions, des récurrences, de nouveaux agencements, des problèmes actuels et inactuels qui forgent et orientent l'écoute du théoricien, du créateur et de l'auditeur. En interrogeant la dimension sonore de la perception, de l’action, de l’espace et de la pensée, cette thèse a pour objectif de modifier la façon dont on écoute, crée et pense le son au cinéma.<br>This thesis describes and analyzes the esthetic, material and conceptual conditions that make the acoustic structures of contemporary cinema possible. The refinement of tools used for manipulating sound, the growing importance the sound designer and the emergence of a new space for sounds to coexist in (brought on by Dolby and multichannel sound systems) are factors that, over the past 30 years, have transformed the way we work with and listen to sound in film. These transformations reveal a new paradigm: mixing gradually imposed itself as the creative and perceptual act capable of accounting for our contemporary sensibility. This thesis explores the effects of the “thought process of mixing” (which functions by resonance, simultaneity, dosage and modulation) on the way we hear and understand the cinematographic experience. Working from the accounts of sound designers (Murch, Beaugrand, Thom Allard…), theoretical texts on film sound (Cardinal, Chion, Campam), documentaries on improvisational musicians (Lussier, Glennie, Frith), fiction films with a acute acoustic sensibility (Denis, Van Sant), philosophical texts on perception (Leibniz, James, Straus, Szendy…) and analyses of the cinematographic sound apparatus, this thesis renders audible the tensions, the recurrences, the structural connections and the problems, old and new, that forge and direct the theoretician, the artist and the auditor’s way of listening. By questioning the auditory dimension of perception, action, space and thought, this thesis aims to change the way we hear, create and think cinema.
35
Palmtag, Juri. "Landscape partitioning and burial processes of soil organic carbon in contrasting areas of continuous permafrost." Doctoral thesis, Stockholms universitet, Institutionen för naturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-136383.
Full textAbstract:
Recent studies have shown that permafrost soils in the northern circumpolar region store almost twice as much carbon as the atmosphere. Since soil organic carbon (SOC) pools have large regional and landscape-level variability, detailed SOC inventories from across the northern permafrost region are needed to assess potential remobilization of SOC with permafrost degradation and to quantify the permafrost carbon-climate feedback on global warming. This thesis provides high-resolution data on SOC storage in five study areas located in undersampled regions of the continuous permafrost zone (Zackenberg in NE Greenland; Shalaurovo and Cherskiy in NE Siberia; Ary-Mas and Logata in Taymyr Peninsula). The emphasis throughout the five different study areas is put on SOC partitioning within the landscape and soil horizon levels as well as on soil forming processes under periglacial conditions. Our results indicate large differences in mean SOC 0–100 cm storage among study areas, ranging from 4.8 to 30.0 kg C m-2, highlighting the need to consider numerous factors as topography, geomorphology, land cover, soil texture, soil moisture, etc. in the assessment of landscape-level and regional SOC stock estimates. In the high arctic mountainous area of Zackenberg, the mean SOC storage is low due to the high proportion of bare grounds. The geomorphology based upscaling resulted in a c. 40% lower estimate compared to a land cover based upscaling (4.8 vs 8.3 kg C m-2, respectively). A landform approach provides a better tool for identifying hotspots of SOC burial in the landscape, which in this area corresponds to alluvial fan deposits in the foothills of the mountains. SOC burial by cryoturbation was much more limited and largely restricted to soils in the lower central valley. In the lowland permafrost study areas of Russia the mean SOC 0–100 cm storage ranged from 14.8 to 30.0 kg C m-2. Cryoturbation is the main burial process of SOC, storing on average c. 30% of the total landscape SOC 0–100 cm in deeper C-enriched pockets in all study areas. In Taymyr Peninsula, the mean SOC storage between the Ary-Mas and Logata study areas differed by c. 40% (14.8 vs 20.8 kg C m-2, respectively). We ascribe this mainly to the finer soil texture in the latter study area. Grain size analyses show that cryoturbation is most prominent in silt loam soils with high coarse silt to very fine sand fractions. However, in profiles and samples not affected by C-enrichment, C concentrations and densities were higher in silt loam soils with higher clay to medium silt fractions.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
36
Fujisao, Kazuhiko. "A Study on Maize Productivity under Continuous Cultivation in Farmers’ Fields in Sainyabuli Province, Northern Laos." Kyoto University, 2018. http://hdl.handle.net/2433/232345.
Full text
37
Piccinin, Jorge Luiz. "Modificações no perfil de solo sob plantio direto continuo e com intervenção mecanica sob sucessão e rotação de culturas." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257181.
Full textAbstract:
Orientador: Carlos Roberto Espindola<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola<br>Made available in DSpace on 2018-08-06T00:13:09Z (GMT). No. of bitstreams: 1
Piccinin_JorgeLuiz_D.pdf: 8786874 bytes, checksum: 8dad73f5093ab76d1710ad9b0c02381e (MD5)
Previous issue date: 2005<br>Resumo: Tem-se como objetivo acrescentar esclarecimentos adicionais sobre mecanismos de degradação, transformação e reorganização de atributos morfoestruturais do solo, mediante caracterizações físicas, biológicas e químicas de perfis submetidos a diferentes práticas de manejo. Destaque especial foi dado ao sistema plantio direto, adotando seqüência de culturas em sucessão e rotação, assim como do manejo do solo em sistema contínuo e com interferência mecânica com escarificador. Os estudos foram realizados em LA TOSSOW VERMELHO Distroférrico do Centro Nacional de Pesquisa de Soja (EMBRAPA Soja), em Londrina (PR). Os sistemas estudados foram de plantio direto contínuo há 15 anos e com interferência mecânica na camada superficial a cada três anos, em áreas cultivadas em sucessão e rotação de culturas; uma área sob vegetação natural foi utilizada para comparação dos efeitos estudados. Utilizaram-se as metodologias do Perfil Pedológico e de Manejo, análises fisicas e químicas por horizontes e unidades estruturais homogêneas. O estudo de campo foi complementado com o perfil de raízes, resistência do solo à penetração, coletados dados climáticos, de resíduos orgânicos na superficie do solo e produtividade das áreas estudadas durante cinco anos. Modificações mais acentuadas ocorreram nos primeiros 40 em de profundidade, com maior variabilidade horizontal de unidades estruturais entre 0,05 e 0,25 m de profundidade, com decréscimo da compactação do solo da superficie para subsuperficie, que se desenvolveu de forma localizada no espaço horizontal e somente intra-agregados. As condições morfoestruturais sob rotação de culturas mostraram mais similaridade com as observadas sob vegetação natural, além de menores valores de densidade e maior aporte de resíduos culturais na superficie após a introdução da cultura do milho, na seqüência de culturas. Após três anos da passagem do escarificador tipo cruzador, a densidade foi maior no sistema de rotação, em relação ao sistema contínuo há quinze anos, mas nas áreas de sucessão foram semelhantes. No entanto, o modo de organização estrutural no perfil de solo foi semelhante à condição de solo natural apenas nas áreas sob rotação de culturas. Evidenciou-se que a disponibilidade e retenção da água e nutrientes no solo, assim como o desenvolvimento radicular, é conseqüência da distribuição, continuidade e diâmetro dos vazios, tipo, classe e localização das estruturas, e menos dependente dos valores de densidade de solo. Os valores de densidade estão mais associados aos índices de resistência à penetração do solo, o que não afeta, no entanto, o maior ou menor desenvolvimento radicular, relacionado de forma mais direta a vazios de origem estrutural.
Não se constatou o desenvolvimento de processos de degradação do solo, mas foram caracterizadas diferenças na produtividade em função dos sistemas e manejo de solo e de cultivo avaliados. A adoção de rotação de culturas se revelou essencial para a continuidade de um sistema, principalmente no seu início<br>Abstract: Therefore there's the necessity to add more knowledge about the mechanisms old degradation, transformation and reorganization of morpho -structural ana1ysis models associated with physical, biological and chemical relations when referring to horizontal and vertical zones the soil profile. Special attention was given to the of no tillage system planting adopting the culture sequences in succession an rotation, like the soil management in a continuous system and with mechanical interference. The studies were developed in LATOS SOLO VERMRLHO Distroférrico located in Centro Nacional de Pesquisa de Soja (EMBRAP A Soja), in Londrina (PR). The studied system were no tillage system planting that has been continuous for 15 years and with mechanical interference, aiming at the rupture of superficial layer of soil every three years, cultivated areas in cultures of sucession and rotation and areas under natural vegetation as reference for modifications. In this study they used of cultivation, physical and chemical analyses. In this study they used the methodologies os morfpho-structural analysis and profile cultural, physical and chemical analyses. The study made in the area of roots, soil resistant to penetration, climatic data organic residue in the soil studied areas during five years. The studies describer more perceptive modifications in the first 40 cm of profundity with more horizontal variability of structural units between 5 and 20_25 cm of profundity. With decrease of compression of soil surfase into subsurface which developed itself localizing in horizontal space and only intraa-aggregated.It has become evident that the availability and retention of water and nutruients in soil, the development of roots is a consequence of distribution, continuity and diameter of empty, 1ype, class and localization of structure, and less dependent of value of soil density.It isn't evident the development of process of soil degradation as a productive way, as well a it's not described difference in productivity and due to systems of management and valued cultivation, the adaption of rotation of cultures demonstrates essential to the continuity system, specially in the beginning<br>Doutorado<br>Agua e Solo<br>Doutor em Engenharia Agrícola
38
Blotevogel, Simon. "Etude des transferts élémentaires et mécanismes biogéochimiques dans le continuum sol-plante-vin par l'utilisation de traceurs isotopiques et biochimiques." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30373/document.
Full textAbstract:
Dans l'ouest de l'Europe, une grande importance est accordée à la composante sol dans l'élaboration des vins. La nutrition minérale est la principale voie par laquelle le sol peut avoir une influence sur la vigne et par conséquent sur le vin qui en est issu. Dès lors, ce travail de thèse appréhende la question plus large des transferts élémentaires entre le sol et la plante à travers de l'utilisation d'outils géochimiques en milieu viticole. Une combinaison de techniques impliquant des indicateurs classiques tels que les rapports élémentaires ou des bilans de masses ainsi que des traceurs plus innovants comme les rapports isotopiques du Cu et la résonance paramagnétique électronique (RPE) est utilisée. Dans un premier temps, l'influence du sol sur la composition élémentaire du vin a été étudiée dans plus que 200 vins provenant d'Allemagne, d'Espagne, de France, et d'Italie. A cette échelle, le type de sol (classé comme calcaire ou non-calcaire) et les conditions météorologiques apparaissent comme des critères discriminants. Par la suite, deux parcelles viticoles de Soave (Italie) aux sols contrastés ont été étudiées afin de d´déterminer l'influence du type du sol sur les vignes. Même si les sols présentent des propriétés pédologiques différentes, une pédogénèse complexe a induit des propriétés géochimiques similaires. Dans les vignes, les traceurs élémentaires et biochimiques montrent que la variabilité inter-annuelle et inter-individuelle est plus grande que la différence liée au sol lui-même. Néanmoins, il est possible de déterminer quel est le sol considéré par l'étude des rapports isotopiques du Sr. Parmi tous les nutriments et éléments toxiques généralement étudiés pour leur mobilité dans les sols, le cuivre a été suivi dans la dernière partie de cette thèse, essentiellement du fait de son épandage toujours massif comme fongicide en viticulture. En effet, les pesticides cupriques comme la bouillie bordelaise sont utilisés depuis environ 150 ans en viticulture. Le Cu s'accumule d`es lors dans les sols et les conséquences ´ecotoxicologiques en font un sujet de plus en plus sensible. Parmi les pesticides analysés dans notre étude, les rapports isotopiques du Cu varient autant entre les différents fongicides que dans les sols étudiés dans la littérature, rendant ainsi impossible l'utilisation de ces isotopes comme traceurs d'origine du Cu dans les sols. [...]<br>In western Europe, soil is of primordial importance for wine making. Soil qualities are often discussed and an influence on wine flavor is frequently inferred. However, evidence for a role of soil chemistry on wine composition and taste is scarce, but mineral nutrition of grapevine plants is one possible way of influence. This thesis approaches the complex question of elemental cycling between soil and plant through the use of geochemical tracers in vineyard environments. A combination of traditional tracers such as elemental ratios and mass balances as well as innovative tools such as Cu isotope analysis and electron paramagnetic resonance (EPR) are used on different observation scales. The influence of soil type on wine elemental composition was investigated using over 200 wine samples from France, Germany, Italy and Spain. Results of chemical analysis were then statistically linked to environmental conditions. At this scale, elemental contents of wine vary depending on soil type (calcareous or not), meteorological conditions, and wine making practice. To determine which soil properties can influence the chemical composition of grapevine plants, two vineyard plots on contrasted soils in Soave (Italy) were examined. Soil forming mechanisms were studied along two catenas and subsequently linked to elemental composition of grapevine plants and biochemical markers of plant health. Even though soil morphology was different, complex soil forming processes led to similar geochemical properties of soils. Differences in plant chemical compositions between soil types are small compared to inter-individual and inter-annual variability. However the use of Sr isotopic ratios allows the determination of the pedological origin of plants. In a next step, the fate of Cu pesticides in vineyard soils was studied. Cu-based pesticides have been used for almost 150 years in European vineyards and Cu accumulates in soils, so that the fate of Cu and its ecotoxicological implications are of growing importance. Therefore, Cu mobility in vineyard soils and transfer to grapevine plants were investigated using stable Cu-isotope ratios and EPR-measurements. Isotope ratios of Cu-based fungicides vary largely between products, covering Cu isotope ratios in soils reported in literature and thus making source tracing impossible. However, Cu isotope ratios are useful for tracing biogeochemical mechanisms of Cu transport in soils. The vertical transport of Cu in different soil types was investigated in the Soave vineyard using a combination of mass balance calculations, kinetic extractions and δ65Cu-isotope ratios. Results suggest that Cu can be transported to depth even in carbonated environments. Besides it is shown that heavy organic-bound Cu is lost from carbonated soil columns likely caused by dissolution of Cu carbonates by organic matter. [...]
39
Jarrousse, Jean-Michel. "Conception d'un convertisseur DC/DC à très haute fréquence pour l'alimentation d'une cellule radar, contributions à son intégration." Cachan, Ecole normale supérieure, 2008. https://theses.hal.science/tel-01199523.
Full textAbstract:
Ce document de thèse traite de la problématique de I'intégration de convertisseurs DC-DC isolés de faible puissance fonctionnant à très haute fréquence et à haut rendement. Pour commencer, I'environnement particulier d'utilisation de ce convertisseur est présenté. II s'agit du domaine des alimentations de radars avioniques, pour lequel les spécifications tant électriques, mécaniques, que CEM sont sévères. Cette partie sert donc de point de départ, car en découle Ie cahier des charges du convertisseur. L'étude qui suit détaille Ie choix de la structure de conversion qui semble la plus adaptée à la fois à I'environnement, mais aussi au cahier des charges. D'autre part, ce document traite de la faisabilité des procédés de cofrittage en vue de la réalisation des composants magnétiques indispensables à la réalisation d'un tel convertisseur. II en decoule Ie choix et la réalisation d'un matériau céramique ferromagnétique spécifique à notre application. Cette étape a conduit à la caractérisation d'un modèle d'évolution des pertes magnétiques en fonction de I'amplitude de I'induction magnétique et de sa fréquence. L'étape suivante presente la mise en oeuvre des outils d'optimisation sous contraintes des éléments magnétiques, tels transformateurs et inductances de résonance. Ces éléments étant composés de notre céramique ferromagnétique adaptee à une fréquence de découpage de 3MHz. Toutefois, I'un des points les plus critiques de cette étude s'avère être la commande rapprochée des interrupteurs de puissance qui a nécessité la mise au point d'une structure originale sans laquelle Ie rendement du convertisseur 3MHz n'aurait pu dépasser les 40% à 50%. Cette structure ainsi que Ie mode de régulation particulier de ce convertisseur ont d'ailleurs donnés lieu à plusieurs brevets. Pour conclure, ce rapport de thèse présente Ie prototype réalisé ainsi que les résultats très encourageants qui ont été obtenus. Un regard critique est porté sur cette réalisation fonctionnelle afin d'ouvrir sur des perspectives de haut niveau d'intégration d'un convertisseur cofritté basé sur cette thèse<br>This thesis report deals with the issue of integration of isolated DC-DC converters operating at low power high frequency and high efficiency. To begin with, the particular environment of this converter is presented. This is the field radar avionics power supply, for which electrical, mechanical, EMC specifications are hard. Therefore, this part is a starting point for the converter specifications. The bellowing study details the choice of conversion structure that seems best for both, the environment but also specifications. On the other hand, this paper discusses the feasibility of co-sintering process for the realization of magnetic components. This components. Which are essential to realized such of converter. It follows the selection and implementation of a ferromagnetic ceramic material specific to our application. This step led to the characterization of a model of evolution for magnetic losses tacking into account the magnetic induction amplitude and the operating frequency. The next step is the implementation of a tools of constrained optimization sizing for magnetic components such as transformers and resonance inductors. These elements are composed of our ferromagnetic ceramic suitable for 3MHz as witching frequency. However, one of the most critical points of this study proves to driver of the power switches. The driver requires a development of an original structure without which efficiency for 3MHz converter couldn't exceed 40% to 50%. Several patents results of this structure, as the particular converter regulation mode. In conclusion, this report presents the realized prototype and the very encouraging results that we have been obtained. A critical eye is focused on this functional achieving to open on the prospects for highly integrated co-sintered converter based on this thesis
40
Petibon, Agnès Chaudot Jean-Pierre. "La formation médicale continue en médecine générale de ses origines à son organisation actuelle." Crétéil : Université Paris-Val-de-Marne, 2004. http://doxa.scd.univ-paris12.fr:80/theses/th0232644.pdf.
Full text
41
Blondet, Vanessa. "Les pratiques sédatives en unités de soins palliatifs, entre travail du care et négociation." Thesis, Strasbourg, 2019. https://publication-theses.unistra.fr/restreint/theses_doctorat/2019/Blondet_Vanessa_2019_ED519.pdf.
Full textAbstract:
Quels sont les différentes formes de la sédation en unité de soins palliatifs ? Comment les sédations sont-elles négociées entre les soignants, le patient et ses proches ? Qu’est-ce que l’usage du Midazolam et sa négociation nous dit du travail en unité de soins palliatifs en France ? Cette thèse repose sur une enquête qualitative menée auprès de quatre structures de soins palliatifs différentes. Le travail s’appuie sur des observations directes et indirectes au sein des structures, le suivi des évolutions dans les doses de Midazolam pour 42 patients, ainsi que soixante entretiens semi-directifs. L'analyse des matériaux montre l’existence de huit usages du Midazolam, dont cinq pratiques sédatives. Les entretiens révèlent que le travail en soins palliatifs vise notamment à (re)socialiser la fin de vie. Cette visée entre en contradiction avec la mise en place d’une sédation profonde et continue jusqu’au décès, ce qui amène parfois les équipes à préférer une sédation plus progressive<br>What are the different type of sedation in palliative care units ? How caregivers, patients and relatives negociate any kind of sedation ? What are uses of Midazolam and its negociation saying about the work in palliative care units in France ? This thesis is based on a qualitative survey, conducted among four palliative care structures. The work is based on direct and undirect observations, tracking Midazolam doses progression for 42 patients, and sixty semi-structured interviews. Materials analysis show eight Midazolam uses and among them, five sedations types. Semi-structured interviews show that palliative care work seek notably end of life (re)socialisation. Yet, there is a contradiction between this goal and the implementation of continuous deep sedation until death. Therefore, caregivers sometimes prefer a more progressive form of sedation
42
Mestelan, Silvia A. "Impact of long-term no till and plow till on soil properties and soil nutrient cycling." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1199221756.
Full text
43
Duncan, Carla S. "Carbon and nitrogen dynamics on a forest site receiving continual papermill sludge applications : a soil column study /." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10102009-020250/.
Full text
44
Depaquy, Antoine Marty Jean-Michel. "Intérêt de l'audit des pratiques dans l'évaluation des séminaires de formation médicale continue." [S.l.] : [s.n.], 2007. http://www.scd.uhp-nancy.fr/docnum/SCDMED_T_2007_DEPAQUY_ANTOINE.pdf.
Full text
45
Tomczyk, Martyna. "Sédation continue, maintenue jusqu'au décès : quelle communication dans les unités de soins palliatifs en France et en Pologne ? Pour une éthique de la présence à l'autre." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCB214/document.
Full textAbstract:
Cette thèse d’éthique médicale, située dans une approche interdisciplinaire et tentant de s’affranchir de tout préjugé personnel de la part de l’auteur, tend à apporter un éclairage, aussi objectif que possible, sur une question, jusqu’à présent, inexplorée : la communication sur la sédation continue, maintenue jusqu’au décès, dans les unités de soins palliatifs, en France et en Pologne. En premier lieu, une recherche bibliographique a été réalisée et les principales failles des publications existantes ont été mises en exergue dont deux en particulier : le flou terminologique et conceptuel autour de la notion de sédation dans le champ de la médecine palliative, et de la notion de représentation elle-même. Pour que l’objet de recherche soit correctement cerné, deux notions-clés – la notion de sédation continue, maintenue jusqu’au décès et la notion de représentation – ont été d’abord explicitées, puis articulées entre elles. En second lieu, une recherche qualitative fondée sur l’étude de cas multiples a été réalisée sur le terrain, c’est-à-dire dans différentes unités de soins palliatifs, en France et en Pologne. Deux méthodes qualitatives ont été adoptées : l’analyse de dossiers et les entretiens semi-directifs individuels. Ces derniers ont été réalisés auprès des principaux acteurs impliqués dans une situation de communication : les médecins prescripteurs, les infirmières et les proches des malades sédatés. Les malades n’ont pas été interrogés, mais leurs témoignages ont été recueillis via les entretiens avec les professionnels de santé et les proches. Quinze cas complets par pays, soit trente cas en tout, ont été inclus dans l’étude. Les données obtenues ont été analysées à l’aide d’outils linguistiques adaptés. Les résultats ont montré que les représentations de la « sédation continue, maintenue jusqu’au décès », faites par les professionnels de santé, avaient un impact sur la délivrance de l’information. Une certaine influence des contextes nationaux a été observée, dans la plupart des cas. En revanche, les souhaits des malades et de leurs proches, quant au contenu de l’information, étaient les mêmes dans les deux pays. Par ailleurs, ce n’était pas tant l’information stricto sensu qui comptait mais une présence bienveillante. Ce besoin de relation nous a amenés à nous interroger sur une certaine universalité de l’être souffrant, malgré ses particularités, d’où notre proposition d’une éthique de la présence à l’autre. Ne devrait-elle pas être intégrée dans le champ de la médecine palliative ou plutôt dans la médecine toute entière, voire dans nos vies de tous les jours ?<br>This thesis addresses an issue of medical ethics which has previously been investigated, that of communication concerning continuous sedation until death as practised in palliative care units in France and Poland. Using an interdisciplinary approach, free of any personal preconceptions by the author, it aims to provide an objective insight into the issue. A literature review is performed initially which highlights the main flaws in the existing publications of which there are two in particular: terminological and conceptual confusion around the idea of sedation in palliative medicine and its conceptual representation. In order to properly frame the object of research, two key concepts: continuous sedation until death and representation are first clarified and then linked together. Subsequently, a qualitative multiple-case field study is performed in a number of different palliative care units in France and Poland. Two qualitative methods are used: case analyses and individual semi-structured interviews with the main parties involved in the communication process - prescribing clinicians, nurses and the families and friends of sedated patients. Patients were not directly interviewed but their experiences were accounted for via the interviews with the carers and family members. Thirty completed case, fifteen per country, are included in the study. The data obtained are analysed using the appropriate linguistic tools. The results show that carers' representations of “continuous sedation until death” influence the delivery of information to patients. The national contexts are seen to exert a certain influence in most cases. However, with regard to the content of information, the wishes of patients and family members are the same in both countries. Moreover, it is less the information itself that counts as much as the caring way it is delivered. The emergence from this study of a needful wish to be cared for leads us to question whether, despite individual differences, there is not a universal dimension to the suffering being. This in turn prompts our suggestion of an ethical scope to the presence of the other. Should this not be at the root of palliative medicine and moreover throughout the entire field of medicine? And if that's the case, why not in our everyday lives ?
46
Whelan, Brett Michael. "Reconciling continuous soil variation and crop yield : a study of some implications of within-field variability for site-specific crop management." Thesis, University of Sydney, 1998. https://hdl.handle.net/2123/27516.
Full textAbstract:
Within-field variability in cropping system attributes is often obvious but difficult to accurately and efficiently quantity. The magnitude of the variation also changes with attribute, location and time. Importantly, variability at this scale of the soil/crop system may give rise to economic, environmental and societal problems on cropping enterprises under traditional 'uniform' management. In general, the problems arise from a decision to use 'mean-of-field' information to guide the amelioration of an area which may result in zones being under-or over-treated. Gathering data on, and extracting useful management information from, within-field variability is the goal of Precision Agriculture.
47
Seward, Linda. "The effect of Continuous Flight Auger pile installation on the soil-pile interface in the Mercia Mudstone Group." Thesis, City, University of London, 2009. http://openaccess.city.ac.uk/18263/.
Full textAbstract:
The research reported in this dissertation examines the physical and chemical changes that occur to in situ soil at the soil-pile interface for continuous flight auger piles installed in the Mercia Mudstone Group. Four Continuous Flight Auger (CFA) piles were installed in the Gunthorpe Member of the Mercia Mudstone Group, central England. The effect on the soil-pile interface of overrotation of the auger during installation, and the addition of water during installation were investigated. Once the piles had been left to cure, they were excavated and returned to City University, London, with the surrounding soil. The excavated piles and soil were examined using a variety of microscopic and macroscopic techniques including inductively coupled plasma spectroscopy (ICP) and X-ray diffraction (XRD); with water contents, chemical content (ICP) and mineralogical content (XRD) tested. Plastic index and particle size distribution tests were used to show the physical effects of piling on the host soil and preliminary strength testing was carried out to provide insight into the strength characteristics of the soil surrounding the pile. In all four piles a distinct zone of remoulding was observed around the pile shaft. In each case the remoulded zone was a brown to red, clay rich layer varying between 0mm and 55mm in thickness. In almost all cases this remoulded zone had a structure and fabric which was not related to the in situ soil. Around all piles it was further noted that vertical fissures were present, and fanned out from the pile shaft in a clockwise direction. Two of the piles were installed with the addition of water. Around these piles it was noted that the remoulded layer often split into two or three distinct layers, with one of these layers often containing millimetre scale aggregations of green silt. Tests showed a higher percentage of clays present within this remoulded zone, and indicated that SiO2 (a major rock forming element and considered by some authors to be an aggregating agent within the Mercia Mudstone Group) was more abundant within remoulded than undisturbed soil. The clay fraction showed a low abundance of high swelling clays in all cases. It was concluded that installing piles within the Mercia Mudstone Group causes remoulding of the soil directly adjacent to the pile shaft. The least remoulding occurred when the pile was augered normally with no added water. All four remoulded zones contained fissures, fanning clockwise from the pile, however, these were more pronounced in the dry piles, while the wet piles had a more massive, granular texture to the remoulded zone. For all piles, except the pile which was over-rotated and installed with no added water, the percentage of clays within the remoulded zone was greater than outside the remoulded zone. This indicates that the aggregates of clays found naturally within the Mercia Mudstone Group may be split into their constituent clays during the piling process.
48
Pulcini, Céline. "Evaluation et amélioration de l'utilisation des anti-infectieux en pathologie humaine." Thesis, Montpellier 1, 2010. http://www.theses.fr/2010MON1T004.
Full textAbstract:
La maîtrise de la résistance bactérienne passe par une amélioration de la prescription des anti-infectieux en pathologie humaine. L'objectif de ce travail était de mettre au point et d'évaluer l'impact d'une intervention destinée à améliorer la qualité de l'antibiothérapie, en ciblant en priorité les prescriptions hospitalières. Nous avons voulu utiliser des stratégies dérivées des sciences sociales et de l'industrie, notamment les techniques d'amélioration continue de la qualité, pour changer le comportement des prescripteurs. Nous avons ensuite ciblé une étape-clé de la prescription antibiotique, i.e. la réévaluation des antibiothérapies probabilistes 24-96 heures après leur initiation, que nous avons sélectionnée à l'issue d'une revue de la littérature et d'une analyse quantitative par questionnaire des perceptions, attitudes et connaissances des prescripteurs ; le questionnaire permettait également d'approcher les barrières locales à cette intervention. Puis nous avons mis au point des indicateurs de processus permettant de mesurer cette réévaluation des antibiothérapies. Enfin, nous avons étudié l'impact sur la qualité de l'antibiothérapie d'une intervention utilisant une stratégie d'audit et de retour d'information, visant à améliorer la documentation de la réévaluation des antibiothérapies par des médecins non-infectiologues dans deux services. En conclusion, les stratégies d'amélioration continue de la qualité s'avèrent utiles pour promouvoir le bon usage des anti-infectieux<br>Antibiotic stewardship is essential to curb bacterial resistance in humans. Our aim was to design an intervention to improve the quality of prescription of antibiotics, focusing on the inpatient setting. We used strategies derived from the social sciences and the industry, particularly continuous quality improvement techniques, to lead the doctors to change their behaviour. We focused on a key process of antibiotic prescribing, i.e. reassessment of antibiotic therapies 24-96 hours after their start ; we selected this process based on a review of the literature and on the results of a survey designed to assess the perceptions, attitudes and knowledge of the prescribers. This survey also enabled us to approach potential barriers to the intervention. We designed then a set of process measures of quality of care in the reassessment of inpatient empirical antibiotic prescriptions. Finally, we assessed the impact of an intervention designed to improve the documentation of the reassessment of inpatient empiric antibiotic prescriptions on the quality of these prescriptions ; this intervention was conducted on two wards and targeted non-infectious diseases specialists, using an audit and feedback approach. In conclusion, continuous quality improvement strategies are a valuable tool to improve antibiotic use
49
George, Eckhard [Gutachter], Michael [Gutachter] Bahn, and Arthur [Gutachter] Gessler. "Plant and soil microbial responses to drought stress in different ecosystems: the importance of maintaining the continuum / Gutachter: Eckhard George, Michael Bahn, Arthur Gessler." Berlin : Humboldt-Universität zu Berlin, 2017. http://d-nb.info/1190292556/34.
Full text
50
Barraza, Castelo Fiorella. "Evaluation de l'exposition humaine liée aux activités pétrolières en Equateur : de la surveillance de la qualité de l'air à l'étude du transfert des contaminants métalliques dans le continuum sol-plante." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30168/document.
Full textAbstract:
L'Équateur est le 5ème pays producteur de pétrole en Amérique du Sud. Les étapes d'extraction et de raffinage génèrent des déchets contentant des métaux co-émis avec les hydrocarbures aromatiques polycycliques (HAPs), connus pour leurs effets cancérogènes et toxiques chez l'homme. Dans ce contexte et dans le cadre du programme ANR MONOIL, le premier objectif de cette thèse était de déterminer la distribution des métaux dans l'environnement sur les provinces d'Orellana et Sucumbíos (zones d'extraction du pétrole en Amazonie, " NAR ") et dans la ville d'Esmeraldas (raffinerie, sur la côte Pacifique," NPC "). Le 2ème objectif était d'étudier le transfert des métaux depuis le sol ou l'air vers les cacaoyers, largement cultivés en Equateur, et d'en déterminer les impacts sur la santé après ingestion. Enfin, le 3ème objectif était de surveiller la qualité de l'air (PM10) afin d'évaluer l'impact des activités anthropiques et le potentiel oxydatif des particules. Des sols et des cultures ont été collectés dans 31 fermes entre 2014 et 2016. Des échantillons d'air ont été prélevés mensuellement sur 3 sites, à proximité des plateformes pétrolières et de la raffinerie. La composition chimique (teneurs en métaux, carbone organique et élémentaire, ions, sucres, polyols, HAPs) a été déterminée dans les PM10. L'évaluation des risques sanitaires a été réalisée via 3 voies d'exposition. Les effets non cancérogènes et cancérogènes ont été quantifiés à l'aide de l'Indice de Risque (HI) et du Risque Total de Cancer (TCR). La bioaccessibilité du Cd par ingestion a été déterminée avec le test BARGE dans les pâtes et fèves de cacao. La formation d'espèces réactives de l'oxygène (ROS) a été quantifiée par spectrophotométrie en utilisant 3 essais acellulaires: DTT, AA et DCFH. Les résultats montrent que dans 72% des sites, les concentrations en Ba, Co, Cu, Cr, Ni, V et Zn dans les sols dépassent les limites de la législation équatorienne. Pour la plupart des cultures, les concentrations en métaux sont inférieures aux limites de détection, sauf pour le Cd dans le cacao et le Pb dans le manioc, qui dérogent aux normes de qualité alimentaire. Les cacaoyers accumulent le Cd dans les feuilles, les cabosses et les fèves. Comme la teneur en Cd du pétrole est inférieure à la limite de détection, les produits agrochimiques et les intrants organiques peuvent être incriminés. Près de 100% de la teneur totale en Cd dans les pâtes et fèves de cacao est bioaccessible par ingestion. Le risque pour la santé après consommation de chocolat oscille entre faible et élevé, selon la quantité ingérée. Dans les PM10, le Ba et le Mo, traceurs spécifiques des activités pétrolières, ont montré des valeurs beaucoup plus élevées que celles enregistrées dans les sites industriels. Les ratios OC/EC étaient plus élevés en Amazonie, suggérant des émissions biogéniques plus importantes. La teneur en HAPs est plus élevée sur la côte, cependant les niveaux de BaP étaient inférieurs aux limites de l'UE. Les résultats du potentiel oxydatif ont montré que les composés émis par l'industrie pétrolière (HAPs, Ba, Ni, Zn), par la combustion de la biomasse (sucres) dans le NAR ainsi que les traceurs industriels dans le NPC (As, Ba, Ni, NH4+) corrèlent avec la génération de ROS. Les principales voies d'exposition aux métaux sont l'ingestion et l'inhalation et, dans une moindre mesure, le contact dermique avec le sol. Les enfants tout comme les adultes sont vulnérables aux effets toxiques de ces composés. Enfin, d'autres facteurs comme la déforestation, l'agriculture et les émissions naturelles (volcans) dans le NAR mais aussi les industries dans le NPC contribuent également aux dégâts environnementaux constatés et aux effets néfastes sur la santé<br>Ecuador is the 5th crude oil producer country in South America. Oil extraction and refining generate toxic waste containing metals co-emitted with polycyclic aromatic hydrocarbons (PAHs), naturally present in crude oil or added during production, and known for their carcinogenic and toxic effects in humans. In this context and as a part of the ANR MONOIL program, the first aim of this PhD research was to determine the distribution of metal(loid)s in the environment in the provinces of Orellana and Sucumbíos (oil extraction, North Amazon " NAR ") and the city of Esmeraldas (oil refining, North Pacific Coast, " NPC "). The second aim was to determine if there was a transfer of toxic metals, such as Cd, from soil or air to cacao crops, widely cultivated in Ecuador, and if the consumption of cacao-based products could imply risks for human health. Finally, the third aim was to monitor air quality over 2 years in both areas to assess the impact of anthropogenic activities and the oxidative burden of particulate matter (PM10). Soils and local crops were collected in 31 small-scale farms, between 2014 and 2016. Monthly PM10 samples were collected in 3 sites, in the vicinity of oil platforms close to the refinery. PM10 chemical composition (contents in metals, organic and elementary carbon (OC, EC), ions, sugars, polyols, PAHs) was determined. Human health risk assessment was performed taking into account ingestion, inhalation and dermal contact. Non carcinogenic and carcinogenic effects were quantified using the Hazard Index (HI) and the Total Cancer Risk (TCR). Bioaccessibility of Cd after ingestion was determined by the BARGE in vitro test in cacao beans and liquors. In aerosols, reactive oxygen species (ROS) formation was quantified using 3 acellular assays: DTT (dithiothreitol), AA (ascorbic acid) and DCFH (2',7'-dichlorodihydrofluorescein). Ba, Co, Cu, Cr, Ni, V and Zn concentrations in 72% of the study soils exceeded the limits of the Ecuadorian legislation. For most of the crops, elements were below the limits of detection but, Cd in cacao and Pb in manioc were above the international standards for food quality. Cacao trees accumulate Cd in leaves, pod husks and beans. Because Cd contents in crude oil were below the detection limits, agrochemical products and natural inputs may also be important sources. Almost 100% of the total Cd content in cacao beans and liquor was bioaccessible by ingestion. The health risk after chocolate consumption was low to high, depending on the ingestion rate and the cacao liquor percentage. In PM10, As, Cd, Ni and Pb were below the EU thresholds. However, Ba and Mo, specific tracers of oil activities, used as weighting agents or catalyzers during drilling and refining, showed values much higher than those recorded in other urban-industrialized sites. PM10 composition depended on oil activity. OC/EC ratios were higher in the NAR (oil extraction) than in the NPC (oil refining), suggesting that biogenic emissions were more important in the Amazon area. PAHs contents were higher in the NPC, but levels of benzo-a-pyrene were below the EU limits. Oxidative potential results showed that compounds emitted by oil industry (PAHs, Ba, Ni, Zn) and by biomass burning (sugars) in the NAR as well as industrial tracers in the NPC (As, Ba, Ni, NH4+) were correlated with ROS generation. Regarding residential exposure, the main routes of exposure to metal(loid)s were first ingestion, inhalation and in a small extent soil dermal contact, being both children and adults vulnerable. Finally, the oil Ecuadorian environment is not only contaminated by oil activities. Other factors like deforestation, agriculture and natural emissions (volcanos) in the NAR and industries in the NPC also contribute to environmental damages and may lead to adverse health effects