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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.
71

What's Inside? An Examination of the Characteristic Microbiome of Prairie Grasshoppers and Katydids

Muratore, Melani K. 22 June 2020 (has links)
No description available.
72

A Quantitative Study of the Relationships between Activity Limitation and Participation Restriction among Older People with Vision Impairment and Comorbid Conditions

Sansing, William K 09 May 2015 (has links)
The purpose of the study was to investigate the prevalence and effects of vision impairment co-existing with other comorbid conditions. Utilizing the 2008 National Health Interview Survey, the most recent nationally representative data including expanded vision, health conditions, and activity questions, this study examined the effect of vision impairment co-existing with selected comorbid conditions among non-institutionalized older adults age ≥ 55 years. Specifically, this study compared 4 groups: (a) older adults with neither vison impairment nor comorbid conditions, (b) older adults with vision impairment only, (c) older adults with comorbid conditions only, and (d) older adults with both vision impairment and each of the comorbid conditions to examine the prevalence and effect of vision impairment and comorbid conditions on selected mobility and vision activity limitations, and participation restrictions. Using complex sample techniques to conduct frequency analyses and logistic regression procedures, this study compared these groups of older adults to document the likelihood of experiencing mobility and vision activity limitations, and participatory restrictions. These results suggest that older adults reporting vision impairments are a heterogeneous population, overwhelmingly use corrective lenses, and experience substantial mobility and vision activity limitations, and participatory restrictions; however, relatively few report using low vision aids or rehabilitation services. In addition, these results revealed, even when controlling for age, sex, race/ethnicity, marital status, region of residence, and health status, older adults with vision impairment and any of the selected comorbid conditions were statistically significantly more likely to report mobility and vision activity limitations, and participation restrictions. Moreover, when comparing older adults reporting vision impairment co-existing with comorbid conditions older adults reporting either vision impairment only or a comorbid condition only, the results suggest vision impairment had the largest statistically significant effect on the likelihood of mobility or vision activity limitations, or participatory restriction in 29 of the 44 logistic regression analyses. These findings are significant as vision impairment is framed as a public health concern, and can inform improvements in programs and services for older adults. Finally, these findings highlight the need for expanded research examining the effect of specific eye diseases and comorbid conditions among older adults.
73

An Examination of the Cellular Partitioning of Phosphorus in Freshwater Phytoplankton

Duckworth, Robyn M. 31 December 2009 (has links)
No description available.
74

<b>THE NOISE AND INFLUENCE ON FLUORESCENCE MICROSCOPY</b>

Yilun Li (18710446) 03 June 2024 (has links)
<p dir="ltr">Fluorescence microscopy, a cornerstone in biological imaging, faces inherent challenges due to photon budget constraints that affect the signal-to-noise ratio (SNR), ultimately limiting imaging performance. This thesis explores theoretical frameworks to address two fundamental issues: the denoising limit of fluorescence microscopy images and the resolution limit in the presence of photon noise. Firstly, we extend the application of the Cramér-Rao Lower Bound (CRLB) to establish a variance lower bound for image denoising algorithms in fluorescence microscopy. By incorporating constraints specific to the imaging system and biological specimens, we provide a benchmark for evaluating the performance of state-of-the-art denoising algorithms. Our analysis reveals that this lower bound is determined by factors such as photon count, readout noise, detection wavelength, effective pixel size, and numerical aperture of the microscope system. Secondly, building upon the pioneering work by Ernest Abbe and leveraging modern fluorescence and nanoscopy advancements, we propose a novel theoretical framework to quantify the resolving power of fluorescence microscopes under finite photon conditions. This model integrates the traditional diffraction limit with photon statistics to determine the practical resolution limit, highlighting the trade-offs between photon noise and resolution enhancement in techniques like confocal microscopy. This dual approach not only refined the theoretical understanding of fluorescence microscopy's capabilities but also assisted in designing and optimizing more effective imaging protocols. Through these investigations, this thesis provided a comprehensive theoretical foundation for improving fluorescence microscopy imaging techniques, paving the way for future innovations in biological imaging.</p>
75

Effektbegränsning värme : Analys och energieffektivisering av värmesystem på Umeå campus / Power limitation of heat : Analysis and energy efficiency improvements of the heating systems at Umeå campus

Eriksson, Mattias January 2024 (has links)
För majoriteten av Umeå universitetscampus finns en anslutningspunkt för fjärrvärme från Umeå Energi. Under januari 2024 uppstod problem när fjärrvärmeeffekten överskred den abonnerade nivån under några extremt kalla dagar, vilket resulterade i straffavgifter från leverantören. Projektets syfte är att analysera och lösa överbelastningsproblemen genom att hitta och jämföra olika förbättringar för värmesystemen på campus. Effektsignaturer analyserades för utvärdering av variationen i den inköpta fjärrvärmen på Umeå universitetscampus, för drift under och utanför verksamhetstid. Resultaten visar en maximal potentiell effektreduktion på 29,4% vid DVUT (dimensionerande vinterutetemperatur). En strategisk driftstrategi kan tillämpas genom att ändra styrsystemets globala tidsschema till röd dag för att uppnå effektreduktion i byggnader utan närvaro. Detta motsvarar en maximal potentiell ekonomisk besparing på 1,7 miljoner kronor för den totala effektreduktionen. Effektkartläggning av Fysikhusets värmesystem utfördes. Resultatet vid DVUT visade att radiatorerna endast stod för 30% av fjärrvärmeeffekten, LA001 (ventilationsaggregat i Fysikhuset, laborationssalar) 64% och LA002 (ventilationsaggregat i Fysikhuset, kontor) 6%. Fysikhusets variation i fjärrvärmebehov under och utanför verksamhetstid vid DVUT visar en minimal skillnad på endast 0,3%, vilket främst beror på värmesystemens utformning och verksamheten som bedrivs. Radiatorernas effektbehov i Fysikhuset vid DVUT analyserades vid sänkning av inomhustemperatur från 21°C till 18°C. Resultaten visar en effektreduktion på 8,7kW och en ekonomisk besparing på 5 746kr, jämfört med radiatorernas normala effektbehov på 43,5kW. Sänkning av ventilationsflöde i Fysikhuset enligt BBR (Boverkets byggregler) visar potential för betydande effektreduktion, med möjlighet att minska ventilationen upp till 61,8% under närvaro och 89,1% utanför närvaro, vilket kan leda till en ekonomisk besparing på mellan 4 700 - 59 500kr. Beräkningar visar att för varje grad (°C) sänkning av tilluftstemperaturen i Fysikhusets ventilation kan en effektreduktion på LA001 och LA002 uppnå 4kW och 3,7kW per grad respektive, vid DVUT. / For most of the buildings on Umeå University campus there is one main connection point for district heating from Umeå Energi. In January 2024 problems occurred when the district heating output exceeded the subscribed level during some extremely cold days, resulting in penalty charges from the supplier. The purpose of the project is to analyse and solve the overload problems by finding and comparing different improvements for the heating systems on campus. Power signatures were analysed for evaluation of the variation in the purchased district heating at Umeå University campus, for operation during and outside business hours. The results show a maximum potential power reduction of 29,4% at DVUT (dimensioned winter outdoor temperature). An operating strategy can be applied by changing the control system's global time schedule to public holiday to achieve a power reduction in unoccupied buildings. This corresponds to a maximum potential financial saving of SEK 1,7 million for the total effect reduction. Power mapping of the building “Fysikhusets” heating system was carried out. The results at DVUT showed that the radiators accounted for only 30% of the district heating power, LA001 (ventilation unit in Fysikhuset, laboratory rooms) 64% and LA002 (ventilation unit in Fysikhuset, offices) 6%. The district heating demand variation in Fysikhuset during and outside of operating hours at DVUT shows a minimal difference of only 0,3%, which is mainly due to the design of the heating systems and the operations that are carried out in the building. A power reduction on the radiators in Fysikhuset was analysed by lowering the indoor temperatures from 21°C to 18°C, the results showed a power reduction of 8,7 kW and a financial saving of SEK 5 746. Compared to the radiators normal power requirement of 43,5kW. Reduction of ventilation flow in Fysikhuset according to BBR (Boverket´s building regulations) shows potential for significant power reduction, with the possibility of reducing ventilation up to 61,8% during attendance and 89,1% without attendance, which can lead to a financial saving of between SEK 4,700 - 59,500. Calculations show that for each degree (°C) lowering of the supply air temperature in Fysikhusets ventilation, a power reduction on LA001 and LA002 can reach 4kW and 3,7kW for each degree respectively, at DVUT.
76

Activity Limitations and Life Satisfaction: A Cross-sectional Study among Amputees in an Orthopaedic Rehabilitation Centre in Ghana

Bredu-Darkwa, Peter, Owusu, I. 03 October 2024 (has links)
Yes / The aim of this article is to examine the limitations encountered by amputees in the performance of Activities of Daily Living (ADLs) and Instrumental Activities of Daily Living (IADLs) and its impact on their life satisfaction. A quantitative cross-sectional study was conducted among 200 amputees at the Nsawam Orthopaedic Training Centre (OTC). The Groningen Activity Restriction Scale (GARS) and the Life Satisfaction Questionnaire-11 (LISAT-11) were used to collect data from the respondents. All statistical analyses were made using IBM Statistical Package for the Social Sciences (SPSS) software 23.0 and summarized in tables. A multivariate analysis was used to establish the relationship between activity limitation and life satisfaction. The respondents experienced some limitations in executing ADLs and IADLS with an overall mean activity limitation score of (36.57±10.93). There was a moderate life satisfaction of respondents with a mean score of (3.86±1.15). A multivariate analysis revealed that, there was a strong negative statistically significant relationship between activity limitations and life satisfaction [ß =--0.13, p=0.000] The government of Ghana through the Ministry of Health and its agencies who are involved in the management and rehabilitation of amputees must explore these limitations to inform decision making during the planning and preparation of rehabilitation programs, resource allocation, and policy formulation for amputees to improve their overall satisfaction and well-being.
77

Etude des possibilités de valorisation des pentoses par fermentation alcoolique d'hydrolysats de paille de blé. / Ethanol production by microbial conversion of pentoses from wheat straw hydrolysates

Fromanger, Romain 20 December 2010 (has links)
La levure Candida shehatae est le microorganisme modèle d’étude choisi. Cette levure peutconvertir le xylose et le glucose en éthanol, contrairement à Saccharomyces cerevisiae, levuretraditionnellement utilisée dans les procédés industriels, qui ne peut convertir le xylose.L’optimisation des performances de production d’éthanol à partir de xylose passe par unemaximisation des trois critères suivants : la productivité volumique, le titre final et lerendement éthanol/xylose. Pour diriger le flux de carbone vers la production d'éthanol defaçon optimale, le paramètre majeur qu’il faut contrôler est le degré de limitation en oxygène.Les cultures sont réalisées sur milieu minéral en mode fed-batch et conduites en deux phases :aérobie puis limitation en oxygène. Une valeur moyenne de la vitesse spécifique derespiration (qO2) de 1,19 mmolO2/gX/h permet de maximiser les trois critères deperformances sur xylose : le rendement en éthanol (0,327 gETOH/g-xylose), la productivitéspécifique maximale (0,22 gETOH/gX/h) et le titre en éthanol final (48,81 g/L). Pour lafermentation du glucose, le rendement en éthanol le plus élevé (0,411 gETOH/g-glucose) estobtenu lorsque qO2 est faible et a pour valeur moyenne 0,30 mmolO2/gX/h; tandis que laproductivité spécifique et le titre en éthanol final atteignent les valeurs maximales de 0,35gETOH/gX/h et 54,19 g/L pour respectivement qO2 de 1,7 et de 2,5 mmolO2/gX/h.Pour la consommation simultanée des deux substrats, un phénomène de répression du glucosesur le xylose est démontré par expérience en chemostat de pulse glucose en régime stabilisésur xylose. La simple présence intra-cellulaire des enzymes de la voie du xylose (XR andXDH) ne permet pas la co-consommation efficace des deux sucres et le glucose estpréférentiellement consommé.Afin de structurer la connaissance acquise sur le métabolisme de C. shehatae et pouvoiroptimiser par simulation les co-cultures C. shehatae / S. cerevisiae pour la productiond’éthanol à partir de mélanges xylose/glucose, un modèle cinétique de C. shehatae estconstruit. Ce modèle est validé avec des cultures sur substrats purs (xylose et glucoseséparés). Un modèle cinétique de co-culture est ensuite développé de manière à simulerdifférentes stratégies de fermentation pour l’optimisation de la production d’éthanol surmélange xylose/glucose de type hydrolysats de paille de blé / The yeast Candida shehatae was the model microorganism of the study. This yeast canconvert xylose and glucose into ethanol, unlike Saccharomyces cerevisiae traditionally usedin industrial processes, which cannot convert xylose. Performance optimization of ethanolproduction from xylose is performed through maximization of the following three criteria:volumetric productivity, final ethanol titer and yield of ethanol over xylose. To direct thecarbon flux towards ethanol production, the major parameter which must be controlled is thelevel of oxygen limitation. Cultures are carried out in fed-batch in mineral medium andperformed in two phases: the first one is not limited in oxygen and the second one is oxygenrestricted. A mean value of qO2 equal to 1.19 mmolO2/gX/h maximizes the three criteria ofperformance on xylose: ethanol yield (0.327 gETOH/g-xylose), the maximum specificproductivity (0.22 gETOH/gX/h) and the final ethanol titer (48.81 g/L). For glucosefermentation, ethanol yield is the highest (0.411 gETOH/g-glucose) when qO2 is low as anaverage value of 0.30 mmolO2/gX/h, while the specific productivity and the ethanol final titerreach maximum values of 0.35 gETOH/gX/h and 54.19 g/L for respectively qO2 of 1.7 and2.5 mmolO2/gX/h.For the simultaneous consumption of the two substrates, a phenomenon of glucose repressionover xylose is observed in chemostat experiment with glucose pulse on xylose steady state.The presence of intracellular enzymes of the xylose pathway (XR and XDH) is not sufficientfor efficient co-consumption of both sugars and glucose is preferentially consumed.In order to structure the knowledge obtained on the metabolism of C. shehatae and tooptimize by simulation the co-culture C. shehatae / S. cerevisiae to produce ethanol fromxylose/ glucose mixtures, a kinetic model of C. shehatae is built. This model is validated withpure substrate cultures (xylose and glucose separated). A kinetic model of co-culture is thenbuilt in order to simulate several fermentation strategies to optimize the ethanol productionfrom xylose/glucose mixture similar to wheat straw hydrolysates
78

Biogeochemical cycle of Iron : distribution and speciation in the North Atlantic Ocean (GA01) and the Southern Ocean (GIpr05) (GEOTRACES) / Etude du cycle biogéochimique du fer : distribution et spéciation dans l’Océan Atlantique Nord (GA01) et l’Océan Austral (GIpr05) (GEOTRACES)

Tonnard, Manon 06 July 2018 (has links)
Il est désormais établi que la disponibilité en fer (Fe) contrôle environ 50% de la production primaire des océans du monde. Cependant, les processus régissant l’intensité des puits et des sources du Fe ainsi que la prédominance relative de ces sources au sein des divers bassins océaniques, sont elles-mêmes peu contraintes. Par ailleurs, une fois entrées dans le système océanique, la disponibilité et l’accessibilité des diverses formes de Fe pour les organismes marins restent incertaines. La réactivité du Fe au sein de l’environnement marin dépend de son état d’oxydoréduction et de complexation. Le fer dissous (DFe) est souvent considéré comme la fraction la plus biodisponible pour le phytoplancton et les ligands organiques du Fe augmentent vraisemblablement le temps de résidence du Fe et permettent des concentrations de DFe bien plus élevées que sa solubilité inorganique ne le permet dans l’eau de mer (10 pmol L-1).Dans ce contexte et s’inscrivant dans le programme international GEOTRACES, cette thèse a pour but principal d’implémenter notre savoir du cycle biogéochimique du Fe dans l’océan et ses interactions avec la structure des communautés phytoplanctoniques, en particulier afin de mieux contraindre les formes biodisponibles du Fe. Ainsi, les objectifs de cette thèse reposent sur trois questions scientifiques : 1) Quelles sont les distributions, sources, et puits de Fe ? 2) Quel est le lien entre la structure des communautés phytoplanctoniques et les concentrations en DFe ? 3) Comment la spéciation organique du DFe impacte ses concentrations et sa biodisponibilité ? Ces trois questions ont été explorées sur de deux zones d’études contrastées : l’océan Nord Atlantique (GEOVIDE, GA01 GEOTRACES voyage, PIs G. Sarthou and P. Lherminier) étant occasionnellement et saisonnièrement appauvri en Fe et l’océan Austral (HEOBI, GIpr05 GEOTRACES voyage, PIs A. Bowie, T. Trull, Z. Chase) l’étant de manière permanente. / It is now recognized that iron (Fe) availability dictates the efficiency of the global biological carbon pump such that any perturbation of Fe sources will lead to changes in the carbon cycles with consequences on both other major nutrient cycles and the climate system, controlling about 50% of the worldwide ocean primary production. However, the underlying processes themselves that affect the pathways releasing and trapping Fe, and the relative predominance of Fe sources among the different ocean basins are still poorly constrained. More importantly, the extent to which both the chemical and the physical speciation of Fe are available and accessible for marine organisms, once it enters the ocean, remains uncertain. The reactivity of Fe within the marine environment will depend on its redox and complexation state, with DFe generally considered the most bioavailable form for phytoplankton and Fe-binding organic ligands likely increasing the residence time of Fe that enables enhanced DFe concentrations way above its inorganic solubility in seawater (c.a. 10 pmol L-1).In this context and as part of the international GEOTRACES program, this thesis aims at improving our knowledge on Fe biogeochemical cycle in the ocean and its interactions with the phytoplankton community structure to better constrain the bioavailable forms of Fe. The objectives of this thesis revolve around three scientific questions: 1) What are the distributions, sources, and sinks of dissolved iron? 2) What is the link between the phytoplankton community structure and dissolved iron concentrations? 3) How the organic speciation of dissolved iron affects its concentrations and bioavailability for the phytoplankton community? These three questions were investigated through two contrasted areas: the North Atlantic Ocean (GEOVIDE, GA01 GEOTRACES voyage, PIs G. Sarthou and P. Lherminier) and the Southern Ocean (HEOBI, GIpr05 GEOTRACES voyage, PIs A. Bowie, T. Trull, Z. Chase) the former being occasionally seasonally depleted in Fe, the latter permanently.
79

Production de Polyhydroxybutyrates à partir d'acides gras volatils en culture ouverte : influence du degré de limitation en phosphore sur les réponses cinétiques et les sélections microbiennes. / Production de Polyhydroxybutyrates à partir d'acides gras volatils en culture ouverte : influence du degré de limitation en phosphore sur les réponses cinétiques et les sélections microbiennes

Cavaille, Laetitia 01 June 2015 (has links)
La production de biopolymères de type polyhydroxyalkanoates (PHA) est une alternative attractive pour remplacer, en partie, les plastiques produits à partir de ressources fossiles. Les contraintes techniques imposées par les cultures pures (substrat purifié, stérilité…) impliquent un coût de production qui rend la production de ces bioplastiques difficilement compétitive par rapport à celle des plastiques conventionnels. L’utilisation de cultures non axéniques permettrait de palier les contraintes des cultures pures mais nécessite une étape de sélection des microorganismes producteurs naturels de PHA. A partir d’un inoculum issu de boues d’épuration et de substrats de types AGV (acide butyrique et acétique), une stratégie de limitation de la croissance par le phosphore pour accumuler du PHB a été mise en place. Nous avons étudié, avec les modes de culture fed-batch et continu, le potentiel de sélection de souches productrices et de production de PHA en fonction des paramètres opératoires (taux de dilution) et environnementaux (degré de limitation en phosphore). L’objectif scientifique a consisté à améliorer les connaissances sur le rôle d’une limitation en phosphore selon les conditions opératoires du procédé, tout d’abord sur la nature des souches sélectionnées, et ensuite sur la croissance et l’accumulation de PHB. Pour cela, une démarche associant l’identification des micro-organismes en dynamique par une technique de pyroséquençage, une caractérisation cinétique des micro-organismes sélectionnés, une analyse procédé et le développement d’une modélisation cinétique a été effectué. L’objectif final du travail visait l’optimisation des procédés de production de PHB en culture non axénique : productivité, rendement, titre final en PHB mais aussi fiabilité et robustesse, en vue de définir une stratégie de production optimale de PHA. Les performances atteintes lors des cultures en fed-batch se situent parmi les meilleures de la littérature (70% de PHA) en cultures mixtes sans étape d’enrichissement préalable en microorganismes producteurs. Les résultats ont montré le rôle de la limitation phosphore sur le déclenchement de la production de PHB. En chémostat, l’analyse des paramètres macro-cinétiques, à partir des sélections microbiennes, a révélé des cinétiques de conversion du substrat carboné en PHB, biomasse catalytique et CO2 dépendantes du degré de limitation en phosphore et du taux de croissance. Le taux de phosphore intracellulaire (dépendant du taux de croissance et du degré de limitation phosphore), est le paramètre gouvernant la conversion du carbone. De plus, ce rôle a été observé pour toutes les populations sélectionnées sous limitation phosphore, démontrant un comportement universel de ces populations face à une limitation phosphore. En parallèle, des études dynamiques en batch à partir de ces populations ont permis de caractériser les paramètres cinétiques des souches, montrant une vitesse maximale de production de PHB de 0,6 et 1,2 Cmol/Cmol.h avec acide acétique et butyrique respectivement. Ces hypothèses réalisées à partir des observations expérimentales ont permis l’établissement d’un nouveau modèle cinétique basé sur le rôle du phosphore intracellulaire sur la conversion du carbone. La confrontation de ce modèle aux résultats expérimentaux a conforté et amélioré la compréhension des processus de dilution intracellulaire du phosphore et de stockage de PHB. Ce modèle a également permis d’explorer une large gamme de conditions environnementales et de prédire les comportements microbiens d’organismes producteurs et non producteurs. A partir des résultats observés et du modèle cinétique établi, les performances de différentes configurations de procédés de production de PHA ont pu être discutées : chémostat simple ou double étage, fed-batch, chémostat et batch... Les performances en termes de productivités, taux de PHB intracellulaires, degré de sélection de producteurs et robustesse du procédé sont comparées. / The production of polyhydroxyalkanoates (PHA) is an attractive alternative for plastics produced from fossil resources. The technical constraints imposed by pure cultures (purified substrate, sterilization ...) involve a high production cost of PHA production, and the production of these bioplastics is hardly competitive. The use of non-axenic cultures would avoid the constraints of pure cultures but requires a selection step of PHA producers. From a microbial inoculum (activated sludge) and AGV (butyric and acetic acid), a strategy for limiting the growth by phosphorus to accumulate PHB was established. From fed-batch and continuous culture, we studied the selection of PHA producers and the production of PHA based on operating parameters (dilution rate) and environmental (degree of phosphorus limitation). The scientific objective was to improve knowledge on the role of phosphorus limitation according to the operating conditions of the process, first about the nature of selected strains, and then about the cellular growth and PHB accumulation. For this, an approach involving identification of microorganisms by pyrosequencing method, a kinetic characterization of selected microorganisms, a process analysis and development of a kinetic modeling were performed. The ultimate goal of the work was the optimization of PHB production processes in non-axenic culture: productivity, yield, final PHB concentration but also reliability and robustness, to define an optimal production strategy of PHA. The performance achieved during the fed-batch cultures are among the best in the literature (70% PHA) in mixed cultures without enrichment step of PHA producers. The results showed the role of phosphorus limitation on the PHB production. Thus, it has been demonstrated the importance of degree of phosphorus limitation to maintain cell growth allowing enrichment in PHA producers explaining the high content of PHA obtained. From microbial selections in chemostat culture, the analysis of macro-kinetic parameters revealed conversion kinetics of the carbon substrate in PHB, catalytic biomass and CO2, dependent on the degree of phosphorus limitation and growth rate. The limits on the degree of plasticity of the intracellular phosphorus (ranging from 3.8% to 0.045%) were identified as a function of the specific growth rate. This intracellular phosphorus content (depending on the growth rate and degree of phosphorus limitation), is the parameter governing carbon conversion. Furthermore, this role of the intracellular phosphorus was observed for all populations selected under phosphorus limitation in this study, demonstrating a universal behavior of these populations face to phosphorus limitation. In parallel, dynamic studies in batch reactor from these selected populations were used to characterize the kinetic parameters of the strains, showing a maximum PHB production rate of 0.6 and 1.2 Cmol/Cmol.h with acetic acid and butyric respectively. These hypotheses made from experimental observations allowed the establishment of a new kinetic model based on the role of intracellular phosphorus on carbon conversion. The comparison of this model with experimental results has strengthened and improved the understanding of the mechanisms of intracellular phosphorus dilution and storage PHB. This model was also used to explore a wide range of environmental conditions and predict microbial behavior of PHA producers and non-producing organisms according to the operating conditions in continuous or batch reactor. From the results observed and the established kinetic model, the performance of PHA production processes of different configurations was discussed: chemostat single or two-stage, fed-batch, chemostat plus batch... The productivities, intracellular PHB content, performances of selection and the reliability of the process are compared.
80

Le bien navire et sa fin : essai sur l'évolution des différents états du navire / The ship and its end : essay on the evolution of the statues of the ship with regard to the particularism of the maritime law

Diatta, Jules François 22 January 2018 (has links)
C’est au navire que le droit maritime doit son particularisme, plus précisément au fait qu’il s’expose au risque de mer. On comprend dès lors que les évolutions des règles applicables au bien soient susceptibles d’avoir un impact sur la matière. Ainsi le particularisme du droit maritime ne manquera pas de s’étioler, à mesure que celui du navire se trouvera affecté. Or, le navire est susceptible de connaître plusieurs états qui vont de celui de navire à celui d’épave, en passant par les états de navire abandonné et de navire à démanteler, chacun de ces états du navire faisant intervenir un ensemble de règles juridiques qui lui est applicable. Ce sont les différents statuts du navire. Ils ont connu ces dernières années des évolutions notables de leurs régimes juridiques respectifs, dont le sens et l’influence sur le particularisme du droit maritime sont étudiés dans cette thèse.En effet si la volonté du législateur d’enfermer le navire dans une définition depuis l’entrée en vigueur du code des transports semble manifester une volonté de banaliser l’engin de transport et partant d’atténuer son particularisme, l’intégration des préoccupations et exigences environnementales aux règles gouvernant sa fin révèle, quant à elle, une nécessaire adaptation de la matière. Cette thèse se propose de montrer comment les évolutions du régime juridique des différents états du navire fragilisent davantage le particularisme du droit maritime, ou ce qu’il en reste. L’étude réalisée tend ainsi à démontrer comment le droit maritime qui s’est historiquement construit autour de la nécessité de protéger le navire contre le risque de mer par la mise en mouvement de règles originales se définit désormais de plus en plus comme un droit destiné à protéger la mer contre le navire. Ce mouvement se traduit par une certaine forme d’amarrage progressif du droit maritime au droit terrestre. / It is to the ship that the maritime law owes its particularism, more precisely to the fact that it exposes itself to the risk of sea. One understands then that the evolutions of the rules applicable to the good are likely to have an impact on the subject. Thus the peculiarity of the maritime law would fade if ship peculiarity is affected.However, the ship is likely to know several States that go from that of ship to that of wreck, through the States of abandoned ship and ship to dismantle, each of these States of the ship involving a set of legal rules that it is applicable. These are the different statutes of the ship. In recent years, they have undergone significant changes in their respective legal régimes, whose meaning and influence on the peculiarity of maritime law are studied in this thesis.Indeed, if the will of the legislator to enclose the ship in a definition since the entry into force of the transport code seems to manifest a desire to trivialize the transport vehicle and thereby mitigate its particularism, the integration of concerns and environmental requirements to the rules governing its end reveal, for its part, a necessary adaptation of the subject. This thesis proposes to show how the evolutions of the legal regime of the different statutes of the ship weaken further the particularism of maritime law, or what remains of it. The study carried out thus tends to demonstrate how maritime law, which has historically been built around the need to protect the ship against the risk of the sea by setting in motion original rules, is now more and more defined as a right destined to protect the sea against the ship. This movement is reflected in some form of progressive docking of maritime law to land law.

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