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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

L'appropriation des avoirs criminels : les saisies pénales spéciales garantissant la peine de confiscation, une étape majeure pour une stratégie pénale patrimoniale repensée ? / The recovery of criminal assets. Special penal seizures and confiscation, a major evolution for a new patrimonial penal strategy

Peter, Marc 21 September 2018 (has links)
La lutte contre la délinquance de lucre et de trafic repose aujourd’hui en France sur une stratégie fondée principalement sur l’appréhension des avoirs illicites ainsi générés par cette activité. En pratique, la loi française a conféré aux magistrats, et sous certaines conditions aux enquêteurs, des prérogatives très offensives permettant de placer sous-main de justice des biens patrimoniaux très en amont de la procédure, au plus tôt, et ce indépendamment du droit de propriété et de la présomption d’innocence. Cependant, si la loi a grandement réformé le droit des saisies en créant les saisies pénales spéciales, elle n’a pas donné le cadre à un droit de l’exécution des confiscations. En effet, la confiscation reste le pivot de l’enquête pénale patrimoniale, même si les saisies pénales spéciales en sont aujourd’hui le moteur. Pourtant, l’absence d’une procédure post-sentence est de nature à ouvrir un nouvel espace d’opportunité pour permettre aux condamnés de dissiper une partie de leurs biens. C’est la raison pour laquelle le droit pénal patrimonial français devrait connaître une mise à jour pour conférer à la justice un cadre complet pour garantir que le crime ne paie pas / In France, the money-laundering and trafficking fight is based on a apprehension of the illicit assets strategy. French law give to magistrates, and under conditions to investigators, very offensive prerogatives to seize property assets very early in the proceedings and regardless of the property and the presumption of innocence rights. However, the law largely reformed law of seizures by creating special criminal seizures, it did not provide a framework for confiscation enforcement. Indeed, confiscation remains the pivot of criminal property investigation, although special criminal seizures are now the driving force. The absence of a post sentential procedure is likely to open a new space of opportunity for the convicteds to dissipate part of their property. This is the reason why French criminal law should be updated to give justice a complete framework to ensure that crime does not pay
342

Development of Novel Biocompatible Hydrogel Coatings for Implantable Glucose Sensors

Wang, Chunyan 19 November 2008 (has links)
Due to sensor -tissue interactions, currently none of the commercially available glucose sensors are capable of continuous, reliable monitoring of glucose levels during long-term implantation. In order to improve the lifetime of implanted glucose sensors, two series of biocompatible novel hydrogel coatings were designed, synthesized and the physical properties were measured. Different hydrogels with various 2,3-dihydroxypropyl methacrylate (DHPMA) compositions were coated onto glucose sensors. Results show that the higher freezable water content, swelling rate and uniform porosity that resulted from high DHPMA content increased the sensitivity and shortened the response time of glucose sensors. The linear range of a glucose sensor coated only with hydrogel is short, however, the range can be improved by coating the epoxy- polyurethane (PU) with a layer of hydrogel. Since the hydrogel minimizes the fibrosis and inflammation, it shows promise for use in implantable glucose sensors. However, the in vivo experiment shows only 25% of sensors still worked after 4 weeks. In order to overcome problems present in the first series of experiments, another series of novel hydrogels with various N-vinyl pyrolidone (VP) contents was developed. This study has provided a feasible approach to design and select the properties of the copolymer for coating implantable biosensors. The in vivo experiments demonstrate that a hydrogel coating significantly improved the performance of implanted glucose sensors. In order to suppress the acute inflammation caused by the surgery, dexamethasone-21 phosphate disodium salt (DX-21) was incorporated to a series of poly (HEMA-DHPMA-VP) hydrogels to investigate the drug delivery in vitro. All hydrogels showed a high initial release, followed by slow, long term release during the next hours to days. This release pattern is believed to be optimum for implanted glucose sensors suppressing the acute and chronic inflammation. Water structures in hydrogels swollen in different media water, PBS and DX-21 solution were also investigated. 1HEMA:1DHPMA copolymer and VP-HEMA-DHPMA copolymers imbibed higher freezable water fractions in DX-21 solution. The ratio of transporting water mass to DX-21 mass is 9.6 which is independent of the hydrogel composition.
343

Apport de prévisions météorologiques à échelle kilométrique pour la modélisation du manteau neigeux en montagne / Potential of kilometric-resolution meteorological forecasts for snowpack modelling in mountainous terrain

Quéno, Louis 24 November 2017 (has links)
Le suivi et la représentation de la variabilité du manteau neigeux en montagne sont des enjeux écologiques et sociétaux majeurs. Le récent développement de modèles météorologiques à échelle kilométrique offre un potentiel nouveau pour améliorer les simulations d'enneigement en montagne. Dans cette thèse, nous avons évalué l'apport des prévisions météorologiques du modèle de prévision numérique du temps AROME à 2.5 km de résolution horizontale pour alimenter le modèle détaillé de manteau neigeux Crocus. Les simulations AROME-Crocus distribuées ont d'abord été évaluées sur les Pyrénées de 2010 à 2014, montrant un apport en termes de représentation de la variabilité spatio-temporelle du manteau neigeux par rapport à l'approche par massif du système opérationnel actuel SAFRAN-Crocus, malgré une surestimation des hauteurs de neige. Par la suite, la valeur ajoutée de produits satellitaires de rayonnements incidents a été étudiée pour des simulations d'enneigement dans les massifs alpins et pyrénéens, soulignant leur bonne qualité en montagne mais un impact mitigé sur le couvert neigeux simulé. Enfin, on a montré comment le schéma de microphysique nuageuse d'AROME associé à Crocus permet de mieux prévoir la formation de glace en surface du manteau neigeux par précipitations verglaçantes dans les Pyrénées. Ces travaux ouvrent la voie à une prévision nivologique distribuée à haute résolution en montagne. / Monitoring and representing the snowpack variability in mountains are crucial ecological and societal issues. The recent development of meteorological models at kilometric scale offers a new potential to improve snowpack simulations in mountains. In this thesis, we assessed the potential of forecasts from the numerical weather prediction model AROME at 2.5 km horizontal resolution to drive the detailed snowpack model Crocus. AROME-Crocus distributed simulations were first evaluated over the Pyrenees from 2010 to 2014. They showed benefits in representing the snowpack spatio-temporal variability as compared to the massif-based approach of the current operational system SAFRAN-Crocus, despite an overestimation of snow depth. Then, we studied the potential added value of satellite-derived products of incoming radiations for simulating the snow cover in the French Alps and Pyrenees. These products were found of good quality in mountains but their impact on the simulated snow cover is questionable. Finally, we showed how the cloud microphysics scheme of AROME associated with Crocus enables to better predict ice formation on top of the snowpack due to freezing precipitation in the Pyrenees. These works pave the way for high-resolution distributed snowpack forecasting in mountains.
344

Les céramiques venues du froid… : Formulation, congélation et structuration par ice-templating / The ceramics rising from the cold… : Formulation, freezing and structuring by ice-templating

Lasalle, Audrey 08 June 2011 (has links)
La mise en forme par ice-templating est un procédé d’élaboration permettant via la congélation d’une suspension, d’obtenir des matériaux poreux à porosité contrôlée. L’analyse des mécanismes régissant la congélation de suspensions concentrées en particules et leurs conséquences sur les microstructures poreuses, est très peu développée dans la littérature du point de vue de l’influence de la composition de la suspension, en termes de nature et quantité d’additifs. Les objectifs de ces travaux de thèse sont d’observer et caractériser in situ et ex situ la formation des structures par ice-templating. Il s’agit également d’établir les liens entre la composition des suspensions, le procédé et la morphologie poreuse obtenue pour les structures congelées et frittées qui en découlent. L’évolution de l’avancée du front de congélation d’un panel de suspensions d’alumine aux propriétés caractérisées a été observée par radiographie X et la microstructure des échantillons congelés et frittés a été caractérisée par tomographie X ou par MEB. Nous avons ainsi pu caractériser les différentes étapes de la congélation par ice templating, les microstructures congelées associées, l’influence de la composition de la suspension ainsi que les mécanismes générateurs de défauts. La force ionique générée par la quantité de dispersant, la présence ou non de liant et la vitesse de refroidissement des suspensions sont trois paramètres ayant des conséquences critiques sur la microstructure et sur l’orientation ou la désorientation des cristaux. Nos résultats apportent un éclairage inédit sur les mécanismes de congélation des sols étudiés en géophysique et notamment la formation de glace lenticulaire. / Ice-templating is a processing route used to obtain porous material with a controlled porosity by freezing a suspension. Researches focused on this subject so far revealed a lack of information about mechanisms controlling the freezing of suspensions with a high solid loading and their consequences over porous microstructures, depending on the composition of the suspension in terms of additives nature and quantity. The objectives of this work are to observe and characterize in and ex situ the formation of structures by ice-templating and to establish the relationships between the composition of suspensions, process and porous morphology of frozen and sintered bodies. The advancement of the freezing front of a panel of alumina suspensions, with characterized properties was investigated by X-ray radiography and the microstructures of frozen or sintered samples were characterized by X-ray tomography and SEM. We have defined the different stages of the freezing by ice-templating, the associated frozen and sintered microstructures, the influence of the composition of the suspension and the mechanisms responsible for defects creation. The ionic strength generated by the dispersant quantity, the addition or not of a binder and the cooling rate of suspension are three parameters with critical consequences on microstructures, orientation and disorientation of ice crystals. Our results shed a new light on the freezing mechanisms of soils in geophysics and more particularly the ice lenses formation.
345

Artificial Ground Freezingin Clayey Soils : Laboratory and Field Studies of Deformations During Thawing at the Bothnia Line

Johansson, Teddy January 2009 (has links)
Artificial ground freezing as a method to temporarily stabilize and create hydraulic sealing in urban as well as in rural areas has been used in a number of Swedish construction projects, particularly during the last decade. One problem with the freezing of soil and rock is that fine-grained clayey types of soils have showed a tendency to under certain circumstances, during the thawing process, create a pore water overpressure and to consolidate, despite a change in the external loading conditions. In certain cases, this condition can be a desired effect as the soil mass after a freeze- and thaw cycle acquires overconsolidated properties. The main objectives of this study are, to describe and review the knowledge and current state of practice of artificial ground freezing, to increase the understanding about the conceptual behaviour for prognosis of the vertical deformation concerning artificial ground freezing and to compare and discuss results from laboratory and field studies concerning vertical deformation during thawing process for Bothnia soil. The field studies and the laboratory tests in this research study have been performed with soil from the freezing of the Bothnia Line in the vicinity of Stranneberget. The Bothnia Line is the railway link between Nyland, north of Kramfors, and Umeå. This thesis relates to a part of the Bothnia Line. It deals with the behaviour of soil during thawing by means of temporary stabilization and hydraulic sealing of fine-grained soil through artificial freezing using brine as the cooling agent. However, the reason behind the problem consists of the final deformations due to the thawing process. The general conclusions of this study are; the Bothnia soil water content decreased in mean approximately 14 % after a freeze-thaw cycle, which approximately corresponds to; wth = 0.8w – 1.5 the decrease of the water content has no correlation to the depth below ground surface, in contrast, there is a strong correlation between the undisturbed soil water content and the magnitude of the decrease in water content the soil liquid limit decreases after a freeze-thaw cycle, simultaneously as the relative share of clay and fine silt grains decreases while the relative share of more coarse grains increases the coarser and denser soil created after a freeze-thaw cycle obtains an increased preconsolidation pressure and an increased undrained shear strength. / QC 20100721
346

Thermophysical Properties of Aqueous Solutions Used as Secondary Working Fluids

Melinder, Åke January 2007 (has links)
Secondary working fluids (secondary refrigerants, heat transfer fluids, antifreezes, brines) have long been used in various indirect re-frigeration and heat pump systems. Aqueous solutions (water solu-tions) have long been used as single phase (liquid only) secondary working fluids for cooling in supermarkets, ice rinks, heat recovery systems, heat pumps and other applications. However, aqueous solutions are increasingly used also for freezers in supermarkets and other applications in low temperature refrigeration. Of importance when comparing different secondary working fluids for indirect systems are the following basic thermophysical properties: freezing point, density, viscosity, specific heat, and thermal conductivity. Reliable data of these properties are needed to choose suitable fluid and to make technical calculations of an indirect refrigeration or heat pump system. The main intention of this work has been to select thermophysical property data with good or acceptable technical accuracy of a number of aqueous solutions that can be used by the refrigeration and heat pump industry, rather than focusing on a limited number of property values or scientifically very accurate measuring techniques. A thorough literature search was in view of this made to find the most reliable property values of aqueous solutions. Detailed literature references are given for thermo-physical properties of the following aqueous solutions, without other additives: Ethylene and propylene glycol, ethyl and methyl alcohol, glycerol, ammonia, potassium carbonate, calcium, lithium, magnesium and sodium chlorides as well as potassium acetate and potassium formate. Some laboratory measurements were made of most of the fluid types when literature values were incomplete or deemed unreliable. Methods used are briefly described and results are given. Much of the work was reported on in the Engineering Licentiate Thesis: Thermophysical properties of liquid secondary refrigerants, A Critical Review on Literature References and Laboratory Measure-ments (Melinder 1998a). That material forms the basis for the charts and tables used in the IIR-publication Thermophysical properties of liquid secondary refrigerants (Melinder, 1997). The present thesis reports on an update made since 1998, including re-view work done on two additional fluids not covered in Melinder (1998a). The thesis describes how the selection of property values results in tables and charts intended for the industry. Coefficients for poly-nomial equations are generated from these property values using a Matlab program and this material is intended as a useful tool for computer treatment. Aqueous solution of ethyl alcohol is used as example to see how this process is made. This choice of fluid can also be seen as a test of this method, as the basic thermophysical properties of aqueous solutions of ethyl alcohol present more chal-lenges than the other fluids examined. A comparison is made of a few types of aqueous solutions used as secondary working fluids for two types of applications. The first example is bedrock heat pumps and the second is cooling cabinets in a supermarket. An effort is made to see how the additive con-centration affects the thermal performance. Most aqueous solutions used as single-phase secondary fluids can also be used as ice slurry, a fluid consisting of liquid and ice where small ice crystals are produced, usually with some type of ice generator. The ice crystals are then transported to the cooling object from which heat is removed when ice crystals melt. This results in less temperature change in the cooling object and makes it also possible to reduce the volume flow rate and to use smaller pipe dimensions in the system. In order to choose a secondary fluid for ice slurry use and to make correct technical calculations of the ice slurry system there is a need to examine and evaluate thermo-physical properties and other aspects of ice and of the aqueous solution used. For dimensioning purposes it is of interest to estimate ice mass fraction and enthalpy values and enthalpy-phase diagrams can serve that purpose. This thesis presents enthalpy-phase diagrams made by author that besides isotherms contain lines with ice fraction and lines connecting enthalpies at freezing point and 1, 2, etc. to 10 K below the freezing point curve. / QC 20100609
347

Evaluación de la capacidad fecundante de espermatozoides porcinos refrigerados y congelados

Selles Soriano, Elena 11 December 2008 (has links)
Este trabajo se ha centrado en el estudio de diferentes factores que afectan a la capacidad fecundante del semen congelado, como la velocidad de descongelación y el sistema antioxidante del semen porcino. También se ha estudiado la capacidad predictiva de la fertilidad in vivo que tienen las diferentes técnicas de análisis seminal tanto para el semen congelado como en condiciones de campo para el semen refrigerado. Se pudo determinar que la velocidad de descongelación más rápida tiene un efecto positivo sobre la funcionalidad espermática de las muestras evaluada mediante un sistema de FIV. Igualmente se concluyó también que el sistema de FIV parece ser la mejor herramienta disponible para evaluar la calidad del semen congelado-descongelado. Se evidenció que el proceso de crioconservación del semen supuso una pérdida siginificativa en el contenido de GSH intracelular. Finalmente, se demostró que el análisis seminal sólo puede identificar eyaculados con bajo potencial fértil. / Boar frozen-thawed semen is still a valuable tool as a complement to artificial insemination with fresh semen in some conditions. The objectives were firstly, the design of better freezing methods in order to obtain acceptable semen quality (freezing-thawing procedures) and secondly, to address the question of whether differences in farrowing rate and litter size after the use of different ejaculates could be predicted using the standard semen parameters under commercial conditions.We can determine that the IVF fertilization system seems to be a good tool to evaluate the quality of frozen-thawed boar semen previous to its commercial way. In other way, we found that there was a loss in GSH content after cryopreservation of boar semen and the addition of GSH to the thawing extender resulted in a significant increase in sperm fertilizing ability. Finally, semen analysis, under commercial conditions, allows to identify ejaculates with very low fertility potential. Therefore, it is unlikely to detect fertility differences associated with seminal parameters.
348

Various Durability Aspects Of Slurry Infiltrated Fiber Concrete

Gilani, Adel Mohamed 01 September 2007 (has links) (PDF)
Slurry infiltrated fiber concrete (SIFCON) was first produced in 1979 in the USA, by incorporating large amounts of steel fiber in molds to form very dense network of fibers. The network is then infiltrated by a fine liquid cement-based slurry or mortar. The steel fiber content can be as high as 30 % by volume. This percentage usually does not exceed 2 % in normal fiber reinforced concrete (FRC) for reasons related to mixing and workability. Due to its high fiber content, SIFCON demonstrates unique and superior mechanical properties in the areas of both strength and ductility. Most of previous research work on SIFCON has focused mainly on investigating the mechanical properties of this material. On the other hand, the studies carried out in the field of durability of SIFCON are quite limited. v Therefore, it seemed that it would be worth to study the various durability aspects of SIFCON. In view of the above, the objectives of this study are to investigate and provide information about durability of SIFCON, mainly permeability, resistance to chloride penetration, freezing and thawing and drying shrinkage. This information will help in providing the necessary database and knowledge about the ability of SIFCON to withstand the conditions for which it has been designed without deterioration, especially when it is intended to be used in aggressive environments The investigations included studying the effects of the following on durability of SIFCON: (i) matrix type (slurry or mortar), (ii) fiber contents (7%, 9.5%, and 12% by volume), and (iii) steel fiber geometry (hooked or crimped). The results obtained indicated that SIFCON, especially when prepared using mortar not slurry, has shown good durability characteristics in spite of its apparent high water absorption. The SIFCON made with the highest possible fiber volume fractions showed the best results. However, it was concluded that SIFCON needs to be protected with suitable low permeability overlays to ensure ideal improved performance by protecting the steel fibers exposed on the surfaces especially against chloride attack.
349

Mechanisms of frost adaptation and freeze damage in grapevine buds

Valle, Radu Virgil Badulescu. January 2002 (has links) (PDF)
Disputats. Universität Hohenheim, 2002. / Haves kun i elektronisk udg. Thesis (Ph.D.). 41 ill., 5 tables; approx. 200 ref. Summaries (En, Ge).
350

Nanoparticle formulations of poorly water soluble drugs and their action in vivo and in vitro

Purvis, Troy Powell 01 February 2011 (has links)
Poorly water soluble drugs have been manipulated to make them more soluble, increasing the bioavailability of these drugs. Several cryogenic processes allow for production of drug nanoparticles, without mechanical stress that could cause degradation. The Ultra Rapid Freezing (URF) process is a technique which improves water solubility of drugs by reducing primary drug particle size by producing amorphous solid dispersions. Heat conduction is improved, using a cryogenic material with a high thermal conductivity relative to the solution being frozen to maintain the surface temperature and heat transfer rate while the solution is being frozen. With URF technology, the freezing rate is fixed, which drives the particle formation and determines its characteristics. Supersaturation of drug in aqueous solution can allow for better absorption of the drug via the oral and pulmonary routes. Drug formulations that supersaturate the dissolution media show the possibility for increased bioavailability from an amorphous drug form. If the concentration of drug in solution is significantly increased, higher chemical potential will lead to an increase in flux across an exposed membrane, leading to higher blood levels for an amorphous drug, compared to an identical crystalline formulation. During oral delivery, supersaturated drug concentrations would also saturate PGP efflux sites in the gut lumen, increasing the drug's bioavailability. Saturated PGP sites show zero order efflux kinetics, so increasing the drug concentration in supersaturated biological fluid will increase serum drug levels. High supersaturation levels maintained for prolonged periods would have a beneficial effect on a drug's absolute bioavailability. Pulmonary administration offers therapeutic advantages over more invasive routes of administration. Limited amount of metabolizing enzymes like CYP 3A4 in lung tissue along with avoidance of first pass metabolism are advantages to pulmonary delivery. The objective of the research presented in this dissertation is to show the versatility of nanoparticulate poorly water soluble drug formulations. Due to the reduced particle size and the URF manufacturing process, a wide range of applications can be used with these nanoparticles. Oral and pulmonary administration routes can be explored using nanoparticles, but in vitro cell culture testing can show clinical benefits from this type of processing technology. / text

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