Dissertations / Theses on the topic 'Détection précoce de broutage'
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Zhao, Yanqing. "Contributions à la détection précoce de chatter et à l’identification des bifurcations de période-N basée sur une approche de diagnostic cumulatif." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0250.
Cumulative diagnosis of dynamic systems requires the detection, identification, and characterization of incipient degradations. Its application to high-speed machining, for instance, could rely on period-N bifurcations phenomena analysis to detect and identify early-chatters and improve the quality of milling products and processes. Up to now, many efficient methods were proposed to detect early-chatter and identify period-N bifurcations. But these methods are struggling to implement these tasks reliably and accurately due to the complex nonlinear characteristics of their dynamic behaviors, the noise, and the variation of their operating conditions. The present thesis aims to develop and implement methods of early-chatter detection and period-N bifurcations identification within a real-time cumulative diagnosis approach. Aimed at early-chatter detection, we proposed three detection methods and one identification method for the cumulative diagnosis. The first method can be used to detect early-chatters remotely. The second one detects early-chatter quickly under specific operating and measuring conditions. However, in practice, the operating and measuring conditions are complex and variable. To adapt to different operating and measuring conditions, we proposed a third method, and the latter detects early-chatter reliably. It is also noted that in milling processes, the early-chatter can give rise to a bifurcation of period-N or Hopf type. The machining quality under the bifurcation process of the period-N type is less critical than that under the Hopf bifurcation type. To improve machining productivity and ensure the required machining quality, we can mill the workpiece under the condition of period-N bifurcations. Thus, it is compulsory to identify the early period-N bifurcations for improving machining productivity. For that purpose, we developed a method for identifying the type and size of the period-N bifurcations. We also proved the effectiveness of the proposed methods, using two benchmark milling process models. Besides, the proposed methods can be used for fault diagnosis of other dynamic systems, such as the pulse energy conversion systems or bearing or gearing systems
Zouari, Rafik. "Détection précoce d’instabilité aérolélastique des structures aéronautiques." Rennes 1, 2008. ftp://ftp.irisa.fr/techreports/theses/2008/r-zouari.pdf.
The goal of this thesis is to design useful statistical detection approaches to improve the aeroelastic flutter monitoring during the flight testing process. Flutter monitoring is investigated as a detection problem regarding the deviations of instability indicators. It consists of a combination of a subspace-based identification method to define a residual vector sensitive to a flutter indicator and a statistical CUSUM test for an on-line deviations monitoring with respect to a fixed reference value. This thesis proposes three approaches. The first performs a flutter detection with respect to a reference modal state predicted close to instability using the a priori knowledge of an aeroelastic model and/or experimental flight testing data. The second approach uses an adaptive flutter monitoring through updating the reference state during the on-line test. The third approach exploits detection tests for damping assessment with confidence bounds determination
Surre, Jérémy. "Détection précoce de la sensibilité bactérienne aux antibiotiques." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB078/document.
Following the discovery of antibiotics, the therapeutic successes foreshadowed a future where infectious diseases of bacterial origin would be eradicated. However, in less than a century, the massive use of broad-spectrum antibiotics led to the emergence of resistance thus reducing therapeutic options. My research project aims to understand early bacterial metabolic and morphological changes induced by antibiotics and to contribute to the development of rapid and reliable diagnostic tests to promote the implementation of more targeted antibiotic treatments. By monitoring changes in various metabolic and morphological parameters of bacteria after antibiotic treatment, we have shown the interest of viability markers such as DiBAC4(3), TOPRO®-3 or Alexa FluorTM Hydrazide for rapid detection (<3h) of bacterial susceptibility to antibiotics. In particular, we have shown for the first time that protein carbonylation, which is induced under conditions of oxidative stress and cellular aging, is a universal early marker of bactericidal antibiotic susceptibility. Following this first part of the study, we wanted to understand the mechanisms involved in bacterial response to lethal stress caused by antibiotics. Following this first part of the study, we wanted to understand the bacterial mechanisms involved in response to lethal stress caused by antibiotics. In our experiments, it was observed that when the conditions no longer allowed the organism survival, a fluorescence signal intrinsically linked to the bacterium allowed to predict the fatal outcome after only 2 hours of incubation. Indeed, following a treatment with a bactericidal antibiotic targeting the synthesis of bacterial peptidoglycan (ampicillin), we observed a maximum fluorescence of the cells at the dose of antibiotic corresponding to the Minimum Inhibitory Concentration (MIC). The fluorescence increase of bacterial cells was also observed during the lethal treatment with a biocidal agent (sodium hypochlorite). However, this phenomenon is no longer observable with bacteriostatic or bactericidal antibiotics that inhibit protein synthesis indicating active bacterial metabolism importance. The correlations of spectral properties allowed us to suspect the flavin molecules as responsible for the observed autofluorescence phenomenon. In addition, we showed an overactivation of the biosynthesis pathway of flavin-type cofactors and flavoproteins occurring during ampicillin treatment. Finally, we performed cell sorting and cell survival experiments of ampicillin-treated bacterial populations. Our results showed that highly fluorescent cells have an average survival 5 times higher than low fluorescent cells. This suggests that the fluorescence signal observed is a cellular response mediated by flavonoid compounds in an attempt to survive to antibiotic treatment. Exploratory work suggests that the phenomenon studied in bacteria is conserved among yeasts and human cells. These results open new perspectives in bacterial physiology understanding, the study of bacterial response to exogenous stress and the rapid monitoring of cell viability
Cosin, Charlotte. "Troubles de l'humeur post-AVC, caractérisation et détection précoce." Thesis, Paris, EPHE, 2016. http://www.theses.fr/2016EPHE3051/document.
Stroke is the second leading cause of death and the leading cause of acquired disability in adults worldwide. Over the last twenty years, treatment in the acute phase of stroke has improved considerably. As a result, post-stroke mortality began to decline and the proportion of surviving patients with mild or moderate disabilities has increased. The long-term monitoring of this category of patients allowed to highlight, in a significant proportion of them, the occurrence of high psychological distress. These mood disorders significantly reduce post-stroke quality of life and, therefore, the assumption that put primary emphasis on the motor deficits, sensory or language now begins to move towards the psychological care of patients. These complications are however still insufficiently understood and their management remains unsatisfactory.In this context, the objective of this PhD was to better describe these post-stroke mood disorders and highlight, through objective measurement tools, the existence of risk factors for their occurrence. 91 patients were followed during one year after stroke and were evaluated on cognitive assessments, mood state evaluation, sleep recording and language recording. The results allowed us to better understand the involvement of some variables in the occurrence or progression of some mood disorders, for example sleep fragmentation and post-stroke apathy or affective prosody and post-stroke depression. Cerebellar lesions also appear to be related to the occurrence of post-stroke mood disorders. These results are part of the increasing research on post-stroke mood disorders
Leclère, Brice. "Algorithmes de détection précoce des épidémies hospitalières : synthèse et propositions." Thesis, Nantes, 2020. http://www.theses.fr/2020NANT4023.
Despite the development of syndromic surveillance and of modern decision making methods, outbreak surveillance within hospitals remains mainly manual. Yet, the use of detection algorithms could improve surveillance efficiency, broaden its scope and overall reduce the time spent to accomplish this task. However, the methodological quality of the evaluations published to this date is too low to conclude about the real utility of these tools. We propose in this memoir several key elements of an adequate methodological framework for early outbreak detection, as well as a first data set containing labelled potential outbreaks. This data set can be used by researchers to develop, evaluate and compare detection algorithms. However, as research on surveillance systems and healthcare artificial intelligence tools has shown, implementing these tools can be difficult, and the results observed in real life can be quite different from those of the development phase. It is therefore necessary to use alternative indicators and evaluation methods to assess the real utility of these tools in real life, measuring for example their acceptability, ease of use, costs and impacts on daily practices
Berrichi, Houria. "Détection précoce des troubles de la vigilance : approches neurophysiologiques et comportementales." Toulouse 3, 1994. http://www.theses.fr/1994TOU30233.
Bisson, Guy. "Détection précoce des maladies inflammatoires du poumon : apport de la médecine nucléaire." Mémoire, Université de Sherbrooke, 1989. http://hdl.handle.net/11143/12038.
Ettori, Dominique. "Spectroscopie d'autofluorescence induite par laser appliquée à la détection précoce des tumeurs." Paris 13, 1996. http://www.theses.fr/1996PA132005.
Dubois, Rémi. "Application des nouvelles méthodes d'apprentissage à la détection précoce d'anomalies en électrocardiographie." Paris 6, 2004. https://pastel.archives-ouvertes.fr/pastel-00000571.
Dubois, R. "Application des nouvelles méthodes d'apprentissage à la détection précoce d'anomalies cardiaques en électrocardiographie." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://pastel.archives-ouvertes.fr/pastel-00000571.
Hocepied, Gatien. "Détection précoce de crises d'épilepsie à l'aide d'une modélisation du comportement oscillatoire neuronal." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209579.
Simon, Pascal. "Détection robuste et précoce des pannes oscillatoires dans les systèmes de commandes de vol." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14377/document.
The research work done in this PhD has been caried out in the frame of an industrial convention (CIFRE) between the IMS laboratory and Airbus Operations S.A.S. The thesis deals with robust and early detection of oscillatory failures (OFC: Oscillatory Failure Case) in the Electrical Flight Control System. An oscillatory failure is an abnormal oscillation of a control surface due to component malfunction in control surface servoloops. OFCs have an influence on structural loads, aeroelasticity and controllability when located within the actuator bandwidth. The ability to detect these failures is very important because they have an impact on the structural design of the aircraft. Usual monitoring techniques cannot always guarantee to remain within an envelope with acceptable robustness. In this work, we develop a model based strategy to detect such failures with small amplitude at a very early stage. The monitoring strategy is based on dedicated non linear local filtering for on-line joint parameter/state estimation, allowing for model parameter variations during A/C flight. This strategy is associated with the same decision making rules as currently used for in-service Airbus A380. We propose a method for adjusting the tuning parameters so that various design goals and trades-off can be easily formulated and managed. The performance of the proposed fault detection scheme is measured by its detection delay, its propensity to issue false alarms and whether it permits a failure to go undetected. The proposed technique has been implemented and tested with success on Airbus test facilities including an A380 flight simulator
Bouthillon, Marine. "Dispositif de discrimination entre des micro-organismes et leur environnement pour une détection précoce." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD005.
An acquisition system and its algorithm are designed. Their purpose is contaminants detection as quality control in pharmaceutical industry. Contaminants are colonies of micro-organisms growing on micro-porous membrane. We use 3D surface measurement, which has never been done in a microbiological context. In addition, our contribution is to use an LED based lighting instead of a laser. It leads to an important noise reduction. It allows to decrease micro-organisms incubation period from 14 days in current method to 5 days or less. The height map from the system are processed with an outlier detection method combined to a support vector machine. Colonies show varying and various signals, and artifacts are present in the data. Nevertheless, we have been able to detect with success the presence or absence of contaminants with a rate of 98%
D'Amours, Guillaume. "Détection précoce de la propagation de fissures dans les engrenages droits par analyse vibratoire." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0016/MQ53935.pdf.
Hamadene, Wassila. "Systèmes chaotiques et méthode des récurrences : application à la détection précoce des crises d'épilepsie." Lille 1, 2005. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2005/50376-2005-194.pdf.
Bretagnol, Frédéric. "Les métastases hépatiques expérimentales d'origine colorectale : détection précoce et croissance tumorale après occlusion portale." Paris 6, 2010. http://www.theses.fr/2010PA066120.
Texier, Gaëtan. "Méthode d'évaluation des algorithmes de détection temporelle des épidémies dans le cadre de l'alerte précoce." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5043.
The main goal of this work is to propose an assessment method to evaluate outbreak detection algorithm with the following characteristics: realistic, pragmatic, operational (easy to implement), validated and reproducible. This method will allow testing and evaluating outbreak detection algorithms with the objective to determine their features and limits. To reach this goal, firstly, we propose to model the surveillance process with their associated tasks, the decision-making and the use of ODA in real conditions. A work focused of uncertainty during the outbreak management and identification of possible tools to support the expert decision-making is presented.Secondly, because building a standardized dataset of evaluation is a prior before any evaluation, we proposed a new approach to simulate in few minutes, from published epidemics, realistic outbreak curve. We used a Monte-Carlo sampling approach to solved several problems non treated in literature and identified theχ²divergence to realized the quality control of data simulated. We also proposed a detailed and commented review on published evaluation metrics (>50). An example of ODA evaluation was realized by comparing several change point analysis (CPA) model and expert judgment while seeking to identify the complementarity between human and statistical tool in a goal of help to decision-making
Angermann, Quentin. "'Détection temps réel assistée par ordinateur pour le dépistage précoce du cancer colorectal en vidéocoloscopie'." Thesis, Cergy-Pontoise, 2018. http://www.theses.fr/2018CERG0926/document.
This manuscript presents the work carried out for the development of a new tool dedicated to real-time computer-assisted detection for the detection of colorectal polyps in videocoloscopy, in the context of early detection of colorectal cancer. This cancer remains today associated with a high mortality rate when detected too late. A such tool could help to improve medical care.First of all, an analysis of the state of the art makes it possible to highlight the limitations of current methods. It is then possible to determine the scientific and technical positioning to adopt in order to create an innovative tool dedicated to this detection task.A first phase dedicated to the analysis of still frames confirms or invalidates the possible scientific choices and thus develops an approach in accordance with the constraints imposed by clinical use (processing time, performance in particular). This first method is able to detect polyps in less than 40 milliseconds per image, which is compatible with real time, with good performance (F1 Score of 47.55%).Logically, we are interested in the detection of polyps in videos, which allows to get closer to real exams. In particular, several optimizations (such as temporal coherence) are proposed to benefit from video. The tool is then able to alert the doctor about the presence of polyps in 97.6% of cases (on a set of 36 videos) in real time with only an average processing time of 23 milliseconds per frame.In the end, this tool, which can alert the doctor of the presence of colorectal polyps in real time during the examination, could therefore be part of the clinical routine of videocoloscopy. Future clinical trials will identify possible limitations to be overcome
Barboza, Philippe. "Evaluation des systèmes d'intelligence épidémiologique appliqués à la détection précoce des maladies infectieuses au niveau mondial." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066529/document.
Our work demonstrated the performance of the epidemic intelligence systems used for the early detection of infectious diseases in the world, the specific added value of each system, the greater intrinsic sensitivity of moderated systems and the variability of the type information source’s used. The creation of a combined virtual system incorporating the best result of the seven systems showed gains in terms of sensitivity and timeliness that would result from the integration of these individual systems into a supra-system. They have shown the limits of these tools and in particular: the low positive predictive value of the raw signals detected, the variability of the detection capacities for the same disease, but also the significant influence played by the type of pathology, the language and the region of occurrence on the detection of infectious events. They established the wide variety of epidemic intelligence strategies used by public health institutions to meet their specific needs and the impact of these strategies on the nature, the geographic origin and the number of events reported. As well, they illustrated that under conditions close to the routine, epidemic intelligence permitted the detection of infectious events on average one to two weeks before their official notification, hence allowing to alert health authorities and therefore the anticipating the implementation of eventual control measures. Our work opens new fields of investigation which applications could be important for both users systems
Gheorghe, Anca. "Détection robuste et précoce de l’embarquement et du grippage dans le système de commandes de vol." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14801/document.
The research work done in this PhD has been carried out under an industrial convention (CIFRE) between the IMS laboratory (Bordeaux University, France) and Airbus Operations S.A.S. (Toulouse, France). The thesis deals with two important Electrical Flight Control System failure cases: runaway (a.k.a. hard over) and jamming (or lock-in-place failure) of aircraft control surfaces. Early and robust detection of such failures is an important issue for achieving sustainability goals and for early system reconfiguration. The thesis focuses on the elevator runaway and jamming. Three model-based monitoring strategies are presented. The first approach is based on a dedicated Kalman filtering with optimised tuning parameters. The second method is based on a decision test applied to an identified sensitive direction in the parametric space. Finally, the third solution is based on a sliding mode differentiator. The techniques have been implemented in the flight control computer and validated on Airbus test facilities and during real flight tests. The experimental results confirmed that good level of performance and robustness can be obtained
Gheorghe, Anca. "Détection robuste et précoce de l'embarquement et du grippage dans le système de commandes de vol." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00879224.
Chabrol, Jérôme. "Détection précoce par l'activité caspase de l'apoptose chimio-induite dans les leucémies aiguës myéloïdes de l'adulte." Bordeaux 2, 1997. http://www.theses.fr/1997BOR23075.
Magaud, Emilie. "Intérêts des marqueurs cognitifs dans la détection précoce des sujets à Ultra Haut Risque de psychose." Paris 6, 2011. http://www.theses.fr/2011PA066633.
Diop-Bruckler, Marguerite. "Détection précoce de Ceratocystis fimbriata F. Platani, agent du chancre coloré du platane, par le test Elisa." Montpellier 2, 1991. http://www.theses.fr/1991MON20020.
Bleunven, Angel. "Contribution à la conception d'un système d'imagerie polarimétrique en vue d'applications pour la détection précoce du mélanome." Thesis, Brest, 2016. http://www.theses.fr/2016BRES0088/document.
Melanoma is a rare cancer that develops from the pigmentation cells of the skin. Recently, we notice a significant increase in the number of people affected by this aggressive disease with a poor prognosis (132 000 new cases each year worldwide). The mortality rate of this cancer is very high, which is due to the rapid spread of cancerous cells to other parts of the body. In France, there is a relatively high number of cases detected, especially in Britanny. The tumor is a spot which looks like a mole. If detected early, a levy is sufficient to healing and the risk of recurrence is very low. However, once metastasis spread, the long-term prognosis is very low. Despite recent advances in targeted therapy, the treatments of metastatic melanoma are still limited. In partnership with the Malakoff Mederic group, we are currently developing an optical system for early detection of cutaneous melanoma. It is based on the polarization properties of light. The PhD focuses on the design of the system, from the feasibility study to the final calibration. We also present various tests on samples of simulation. These allow us to demonstrate the correlation between the effects of polarization and biological changes during the development of melanoma. This preliminary study prepares us to experiments on real samples
Jeancolas, Laetitia. "Détection précoce de la maladie de Parkinson par l'analyse de la voix et corrélations avec la neuroimagerie." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLL019.
Vocal impairments, known as hypokinetic dysarthria, are one of the first symptoms to appear in Parkinson's Disease (PD). A large number of articles exist on PD detection through voice analysis, but few have focused on the early stages of the disease. Furthermore, to our knowledge, no study had been published on remote PD detection via speech transmitted through the telephone channel. The aim of this PhD work was to study vocal changes in PD at early and preclinical stages, and develop automatic detection and monitoring models. The long-term purpose is to build a cheap early diagnosis and monitoring tool, that doctors could use at their office, and even more interestingly, that could be used remotely with any telephone. The first step was to build a large voice database with more than 200 French speakers, including early PD patients, healthy controls and idiopathic Rapid eye movement sleep Behavior Disorder (iRBD) subjects, who can be considered at PD preclinical stage. All these subjects performed different vocal tasks and were recorded with a professional microphone and with the internal microphone of a computer. Moreover, they called once a month an interactive voice server, with their own phone. We studied the effect of microphone quality, speech tasks, gender, and classification analysis methodologies. We analyzed the vocal recordings with three different analysis methods, covering different time scale analyses. We started with cepstral coefficients and Gaussian Mixture Models (GMM). Then we adapted x-vectors methodology (which never had been used in PD detection) and finally we extracted global features classified with Support Vector Machine (SVM). We detected vocal impairments at PD early and preclinical stages in articulation, prosody, speech flow and rhythmic abilities. With the professional microphone recordings, we obtained an accuracy (Acc) of 89% for male early PD detection, just using 6min of reading, free speech, fast and slow syllable repetitions. As for women, we reached Acc = 70% with 1min of free speech. With the telephone recordings, we achieved Acc = 75% for men, with 5min of rapid syllable repetitions, and 67% for women, with 5min of free speech. These results are an important first step towards early PD telediagnosis. We also studied correlations with neuroimaging, and we were able to linearly predict DatScan and Magnetic Resonance Imaging (MRI) neuromelanin sensitive data, from a set of vocal features, in a significant way. This latter result is promising regarding the possible future use of voice for early PD monitoring
Salomez, Pierre-Marie. "Caractérisation des fluctuations de pression dans un lit fluidisé en vue d'une méthode de détection précoce des dysfonctionnements." Compiègne, 1996. http://www.theses.fr/1996COMPD905.
Benachenhou, Habib Mustapha. "Intérêt des tests psychométriques dans la détection précoce du psychosyndrome dû aux solvants : intérêt en médecine du travail." Angers, 2003. http://www.theses.fr/2003ANGE0501.
I. Introduction : the solvents are commonly used on a large scale in a great many different professional activities. Such solvents are toxic to the nervous system. The present is an investigation dealing with two (02) types of populations : an exposed and a non-exposed to solvents; aiming at the search for early subclinical disorders induced by solvents. II. Studied population : exposed population : 150 subjects; non-exposed population : 150 subjects exposed neither to any solvents or to any product likely to be neurotoxic. III. Methodology : for undertaking properly this study, it was necessary to measure the level of exposure to solvents, and then, through extrapolation on the past, appraise the quantity of solvent accumulated. Hodgsedt's questionnaire (translated) referring to the subjective symptoms felt during the year preceding the study. Psychometric tests : a battery of WHO neurobehavioral tests including : simple reaction time, test of dexterity (Purdue Pegboard Test), test of pointing, Benton's test of image recognition, test of coding (WAIS code), test of digit memorizing (WAIS Digit-Span test). .
Dutrieux, Sylvain. "Conception d’un implant instrumenté in vivo et du système de détection associé pour prothèse orthopédique : Application à la détection précoce du descellement et au diagnostic post-opératoire." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS115.
Many technical advances have emerged in recent years in medicine and surgery. They allow to live better and longer. While efforts have been made in the development of innovative devices, their in vivo monitoring has shortcomings, particularly with regard to implantable devices, critical entities implanted in a fragile environment. Thus, at present, the fact is that a product of the agri-food industry is better followed than a medical device implanted in a patient. The problems raised by this lack of traceability are numerous: impossibility of controlling medical devices once implanted, impossibility of having well-filled materovigilance registers, for example. In addition, there is also a lack of data on the behavior of implants in vivo, which are essential for their monitoring and improvement. The aim of this thesis is to develop a device capable of both identifying and tracing all knee prostheses in the world, and to provide a means of control of these prostheses once implanted. For this, two devices are studied: a long-term passive electronic implant (with all the constraints imposed by this type of implants: biocompatibility, biostability) and an innovative imaging system, low cost and not exploiting any radiation or products injection
Ni, Zhuoya. "Méthode pour l'estimation de la fluorescence de la chlorophylle et son application pour la détection précoce du stress hydrique." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD022/document.
Sun-induced chlorophyll fluorescence is a new way to monitor the vegetation change and global carbon cycle. Through the model simulated analysis, the pot experiment and the airborne flying experiment, the research on detecting the multi-scale sun-induced chlorophyll fluorescence is developed in this dissertation. The main conclusions and innovations are as follows: 1. The maize water control experiments demonstrate that the passive fluorescence can be used to detect the crop water stress, and the analysis of the different responses of the fluorescence and temperature illustrates that the fluorescence is much sensitive to the early water stress. 2. Analyze the effects of temperature, sun zenith angle and fluorescence quantum efficiency on the qualitative fluorescence retrieval, and propose a qualitative fluorescence retrieval method based on the reflectance index. 3. Analyze the effects of airborne fluorescence retrieval, and obtain that sun zenith angle and airborne sensor height are the important factors to affect the sun-induced fluorescence retrieval from the simulated analysis and airborne flying experiment
Zaremski, Alba. "Les Aphyllophorales impliquées dans la dégradation du bois : caractérisation taxinomique, phylogénie et détection précoce des champignons dans le bois." Aix-Marseille 1, 2005. http://www.theses.fr/2005AIX11078.
After a review of our knowledge about wood and wood decaying fungi, three chapters are developed to improve our understanding of the organization of wood decaying fungi diversity to optimize wood uses. A taxonomical study (PCR-RFLP and ITS sequencing) was carried out on 98 Basidiomycetes degrading wood in cubic and fibrous rots. The analysis of ITS molecular weight allowed to define two clusters: one having an about 635 bases pairs ITS and a second having a 725 bases pairs ITS. Genomic diversity within these isolates has been specified using restriction enzymes. Error in molecular weight assessment of PCR products and restriction fragments was of 12 %. Partly because of that fact, the use of sequencing appeared better adapted for taxononical studies, including the assessment of ITS length. The phylogenetical analyses of ITS performed on 57 collection strains and 96 data bank sequences allowed to evidence groups of cubic rots distinct from groups of fibrous rots. These analyses permited to evidence relationships between phylogeny and function and to specify the taxonomical position of unidentified strains. Lastly, a tool for the early detection of fungi in different wood has been developed. For that purpose, five different woods have been infected by five different strains. In spite of weight losses, generally below 5 % indicating a very low level of infection, a DNA sequence homologous to the strain used was obtained in 21 of the 25 wood/fungus combination tested, demonstrating the pertinence of this method. The work opened new possibilities for further development in the field of wood preservation
Schaefauer, Christof. "Développement d'un prototype clinique d'imagerie d'autofluorescence excitée dans l'UV destiné à la détection précoce des carcinomes de la vessie." Paris 13, 2006. http://www.theses.fr/2006PA132016.
The purpose of this thesis was to conceive and to achieve a clinical prototype for early endoscopic imaging detection of blader carcinomas. The principale is to excite the fluorescence of molecules naturally present in the tissue with 308nm laser pulses. The weak emitted signal is collected by a catheter entirely conceived in the laboratory and which is able to transmit UV images. The fluorescence spectrum is spectrally analysed and then detected by an amplified camera. The intensity ratio of the light emitted around 360 nm and around 450 nm depends on the histopathologic state of the tissue. These two signals correspond to the concentrations of tryptophan and NADH which vary with cell activity. Diagnostic data are treated by computer and shown in real-time on a screen seen by the doctor. A clinical test on 36 patients allowwed to confirm the functionality of the apparatus and the pertinence of method
Saad, Mehdi. "Détection précoce et quantification objective par mesures chronoampérometriques de l’atteinte neurologique périphérique chez des patients recevant une chimiothérapie neurotoxique." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS060/document.
Introduction : Cytotoxic chemotherapy is a treatment modality for many cancers. The improved survival time of patients showed some complications of these cytotoxic treatments including chemotherapy-induced peripheral neuropathy (CIPN). This is a common and potentially severe complication that can have a lasting impact on the quality of life. Although neurotoxic chemotherapies are known, there is no accurate data to predict individual tolerance. Early detection of CIPN is therefore essential to assess the contributing factors. To this end, the use of the TNSc (Total Neuropathy Score clinical view) and the Sudoscan® can improve the detection CIPN.Indeed, the TNSc (Total Neuropathy Score clinical view), a composite score assessing small and large nerve fibers, has been validated to evaluate the severity of CIPN. The nerve impairment concerns the large myelinated fibers or small fibers, depending on the treatment. The objective assessment of large fibers is standardized by means of the EMG (Electromyography), but it is not the same for the diagnosis of the small fibers impairment.On the other hand, the Sudoscan® measures skin conductance (chronoamperometric measurement) after exposure to a direct current of less than 100μA and 6V, and can assess the sudomotor function. Interestingly, studies in diabetes have shown that sudomotor function is directly related to the status of the small fibers that control the sweat glands. The Sudoscan® could thus be used for the detection of CIPN.Objectives: i) to evaluate the impact, depending on the dose received of chemotherapy, of CIPN by TNSc and assess the impairment of small fibers in patients during treatment with Platinum compounds or Taxanes or vinca alkaloids; ii) to study the evolution of the peripheral neurologic impairment by TNSC and skin conductance measurements during chemotherapy and after the end of the treatment; iii) to characterize risk factors for CIPN; iv) to assess the usefulness of conductance measurements compared to TNSc.Results: Particular attention has been given to patients treated with Oxaliplatin (n= 65) and Taxanes (n= 28), known to damage small fibers. We found an increased TNSc in all patients receiving neurotoxic chemotherapy. During follow-up, 57% of patients receiving Oxaliplatin and 58% of patients receiving Taxanes reach a TNSc corresponding to a clinical neuropathy. However, there was no difference of TNSc during the follow-up between symptomatic and asymptomatic patients, 4 months after the end of the treatment by Oxaliplatin. Similarly, we did not find differences of TNSc during the follow-up between symptomatic and asymptomatic patients, 4 months after the end of the treatment by Taxanes.Regarding conductance values, we didn’t observe changes depending on the dose received for patients treated by Oxaliplatin. However, in patients receiving Taxanes we found significant differences, based on the cumulative dose, for the hands and feet. Indeed, the lowest measure of the feet during the tracking is observed within an average of 23 days before the TNSc reached its highest value (p = 0.03). We didn’t find differences in conductance values during follow-up among symptomatic and asymptomatic patients 4 months after the end of their treatment. However, 4 months after the end of the chemotherapy, symptomatic patients treated with Taxanes had feet conductance values lower than asymptomatic patients (p= 0.004). The TNSc was higher in diabetic patients than in non-diabetic patients depending on the dose received during the follow-up. During the follow-up, the conductance values of the hands and feet were significantly lower (p= 0.003) for these patients than in nondiabetic ones.Conclusion: These results suggest that the chronoamperometric measurements can be useful in the detection and quantification of small fibers impairment in patients receiving Taxanes
Tanos, Rita. "Développement de tests diagnostiques par détection d'ADN extracellulaire." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTT054.
After its discovery in 1948, circulating DNA (cirDNA) was studied in various fields. It has become an emerging biomarker, particularly in oncology, and several studies have recently sought to investigate its interest in cancer screening and early detection. The first part of my thesis was devoted to the study of the quantitative and structural characteristics of cirDNA, taking into account its origin (nuclear and mitochondrial cirDNA) and its structure (fragmentation and size profile), for the screening and early detection of cancer. Two cirDNA parameters, the Ref A 67 (total nuclear cirDNA concentration) and the MNR (Mitochondrial to Nuclear Ratio), were quantified by q-PCR in a mouse model and further validated in cell culture media to assess their potential to discriminate between a healthy and a cancerous state. These two variables were evaluated by taking into account other quantitative and structural parameters of cirDNA, after age adjustment, in the plasma of 289 healthy individuals, 99 individuals at risk of colorectal cancer (CRC) and 983 patients with CRC (n = 791), breast cancer (n = 169) and other cancers (hepatocellular, pancreatic, ovarian and lymphoma) (n = 23). Through a machine learning approach, we combined these different parameters into a prediction model using decision trees for the classification of healthy and cancer patients. We have obtained very encouraging results, especially for early-stage cancers. This method seems promising for early and non-invasive cancer detection. The addition of other biomarkers such as the size profile of the cirDNA or the detection of methylation markers could further increase its potential.The second part of my thesis was devoted to the study of the relationship between the quantity of extracellular DNA of nuclear and mitochondrial origin in the embryo culture medium, and the quality of these embryos during in vitro fertilization (IVF). It has been shown that an embryo releases extracellular DNA into the culture medium during IVF, and that this DNA could be a predictive biomarker of embryo quality and thus be used as a non-invasive preimplantation genetic test (PGT). We detected, as well, the SRY gene in the culture medium to determine the sex of the embryo, which is an important information in the case of gender-related genetic disorders. We also tried to detect the presence of the Delta F508 mutation of the CFTR gene responsible for cystic fibrosis, by analyzing extracellular DNA from high-risk embryos to assess its potential as a non-invasive PGT
Montrose, Armelle. "Développement d'un immunocapteur impédimétrique pour la détection et la quantification d'une sous-population cellulaire : application au diagnostic précoce des infections." Toulouse 3, 2013. http://thesesups.ups-tlse.fr/1963/.
Biosensors and lab-on-chips are becoming important tools for diseases diagnosis and treatment monitoring. This work is a part of a research project which aims to design an integrated device for isolation, sorting and counting of cells subpopulations for early and real time diagnosis of infectious diseases. It consists in developing an impedimetric immunosensor to detect inflammatory monocytes found in larger number in the blood of patients with inflammation and infectious diseases. The functionalization for cells trapping via an immunochemical interaction has firstly been optimized on gold electrodes fabricated thanks to microtechnologies. The antibodies grafting lies on a multilayer system consisting of stacking self assembled monolayers and cells adhesion proteins and each assembly step have been characterized by optical and electrochemical techniques for different electrodes sizes. Then, the biosensor performances have been investigated by electrochemical impedance spectroscopy and we successfully demonstrated a selective and quantitative detection of trapped monocytes according to the immobilized antibody. Miniaturization enhancing the detection sensitivity, microelectrodes have been developed. After optimization of the fabrication process and functionalization of the microelectrodes, detection of monocytes has been validated by impedance. The integration of these microsystems in a microfluidic device is actually under development
Girond, Florian. "Mise en place d’un système d’information géographique pour la détection précoce et la prédiction des épidémies de paludisme à Madagascar." Thesis, La Réunion, 2017. http://www.theses.fr/2017LARE0012/document.
We describe a Malaria Early Warning System (MEWS) using various epidemic thresholds and a forecasting component with the support of recent technologies to improve the performance of a sentinel MEWS. Malaria-related data from sentinel sites collected by Short Message Service are automatically stored in a database hosted on a server at Institut Pasteur de Madagascar. Concomitantly our system routinely and automatically acquires site specific satellite weather data related to changes in malaria prevalence such as temperature, rainfall and Normalized Difference Vegetation Index (NDVI). A Malaria Control Intervention data base has also been. This system has already demonstrated its ability to detect a malaria outbreak in southeastern part of Madagascar in 2014. In a second time, we conducted a study to assess the relationship between the effectiveness of mass campaign of long-lasting insecticidal nets (LLIN) over time and malaria outbreaks identified in Madagascar from 2009 to 2015 through the Sentinel surveillance system. This study showed that the difference between efficacy and effectiveness may result in gaps in service coverage during the subsequent years contributing to malaria rebound well before the replacement of the LLINs and highlights the need of continuous distribution mechanism of LLINs.This work aims to maximize the usefulness of a sentinel surveillance system to predict and detect epidemics in limited-resource environments, to guide any changes in the orientation of malaria control programs and to provide practical examples and suggestions for use in other systems or settings
Collin, Samuel. "Optimisation des stratégies de surveillance pour la détection précoce d'un tunicier envahissant par l'évaluation des mécanismes et des patrons de recrutement." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30302/30302.pdf.
The globalisation of human activity has contributed greatly to the artificial dispersal and introduction of non-indigenous species (NIS) around the world. The potential for damage is such that there is great pressure on environmental managers to detect and control problematic NIS (i.e., invasive species) before any impacts occur. By studying NIS, ecologists can examine aspects of species survival, dispersal, and establishment, which, in addition to addressing fundamental questions of ecology, provide vital information for optimizing management effort. However, the difficulties associated with studying and detecting nascent populations has restricted quantitative studies on the processes that precede invasion, leaving environmental mangers with little guidance for detecting NIS. To alleviate this shortcoming, this study provides a quantitative assessment of the determinants of recruitment and dispersal of the notoriously problematic invasive tunicate, Ciona intestinalis (henceforth Ciona), in Prince Edward Island (PEI), Canada, during the early stages of invasion. Recruitment data from a nascent population of Ciona was collected over a two-year period (2008 & 2009), which allowed for dispersal to be modelled (range and peak) and for patterns of recruitment during establishment to be examined. These data highlight the importance of incorporating dispersal, as well as environmental variability, into early-detection monitoring strategies and demonstrate how drivers of recruitment change as the invading population becomes larger and more widespread. Additionally, a series of small-scale manipulative field studies were performed to assess patterns of recruitment during settlement. The respective roles of light and gravity on Ciona larval behaviour were identified and their incorporation into the design of monitoring equipment (to increase settlement rates and, thus, probability of detection) are discussed. Finally, biotic resistance towards NIS was examined by investigating the interactions between Ciona larvae and two species of caprellid amphipod, Caprella linearis (native) and C. mutica (invasive) found in PEI. This study shows how the presence of caprellids reduces Ciona recruitment and illustrates the potential for negative interactions between two NIS (C. mutica and Ciona), a phenomenon rarely documented. From a managerial perspective, these negative interactions can provide valuable insights to potential biocontrol agents. Moreover, this study presents a detailed account of the underlying mechanisms that influence patterns of recruitment of a problematic invader and discusses the utility of these findings for future monitoring and management of invasive species.
Aufort, Marie. "Chimiothèques de complexes du technétium et du rhénium ciblant l'intégrine alphaVbeta3 : développement de traceurs pour la détection précoce de la néoangiogenèse tumorale." Phd thesis, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00339820.
Les traceurs ont été obtenus selon deux stratégies : 1) cyclisation d'analogues linéaires de RGD par un motif NS2/S coordinant un cœur oxotechnétium ; 2) assemblage combinatoire de motifs indépendants par coordination du cœur oxotechnétium par le motif NS2+S. La stabilité des traceurs technétiés et de leurs analogues rhéniés a été testée en présence de glutathion et dans le plasma. Une première évaluation in vitro sur intégrine purifiée a montré que l'un des peptides RGD, cyclisé par le rhénium, se lie spécifiquement à alphaVbeta3. Un modèle tumoral (tumeur U87-MG, implantée sur des souris nude) a été validé au laboratoire et une méthode d'analyse du criblage in vivo a été mise au point à l'aide de composés modèles marqués au 99mTc. Il s'avère que les données de biodistribution et le pourcentage d'activité retrouvé dans la tumeur sont encourageants pour les complexes cycliques, bien que l'identification des traceurs efficaces soit rendue difficile par leur instabilité dans les conditions d'analyse.
Kodewitz, Andreas. "Méthodes pour l'analyse de grands volumes d'images appliquées à la détection précoce de la maladie d'Alzheimer par analyse de PDG-PET scans." Phd thesis, Université d'Evry-Val d'Essonne, 2013. http://tel.archives-ouvertes.fr/tel-00846689.
Aufort, Marie. "Chimiothèques de complexes du technétium et du rhénium ciblant l’intégrine alphaVbéta3 : développement de traceurs pour la détection précoce de la néoangiogenèse tumorale." Paris 11, 2008. http://www.theses.fr/2008PA112204.
Integrins form a family of heterodimeric integral glycoproteins which play a central role in cell-cell adhesion and cell-matrix interactions. In particular, they are overexpressed during tumor neoangiogenesis. About 10 of them recognize a structured RGD (Arg-Gly-Asp) sequence. Analogs of this sequence can be used for the early detection of tumors and metastases. We developed new tracers, labeled with 99mTc, for the molecular imaging of alphaVβ3 integrin. Until recently, there was no reliable ab initio structure prediction of complex molecules containing Re and Tc chelates. Therefore, we preferred a combinatorial approach to develop potential ligands of alphaVβ3 integrin and we attempted to identify efficient tracers by in vivo screening. This method would account for biodistribution and pharmacokinetics properties in the early steps of the study. Tracers were obtained according two strategies: i) cyclization of linear RGD analogs; ii) combinatorial assembling of independent modules through metal core coordination by the well-known NS2+S motif. After synthesis and labeling, the stability of the tracers was investigated in presence of glutathione and in murine plasma. In vitro screening on purified integrin showed that a cyclic rhenium coordinate binds specifically alphaVβ3. A tumor model (U87-MG tumor on nude mice) was validated in the laboratory and a method was developed to analyze in vivo experiments. Biodistribution data and percentage of activity found in tumors are encouraging for cyclic compounds though identification of efficient tracers is difficult due to their instability in the conditions of analyses
Guibbal, Florian. "Développement, synthèse et marquage au fluor-18 de ligands de la Lp-PLA2 pour la détection précoce de plaques d’athérome par imagerie TEP." Thesis, La Réunion, 2017. http://www.theses.fr/2017LARE0017/document.
Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. Atherosclerosis, which leads to the obstruction of large arteries, represents 50% of deaths in industrialized societies. Rupture of a vulnerable atherosclerotic plaque can lead to several complications which, depending on the site, can cause stroke or myocardial infarction.To address this public health issue, there is a real need to develop new diagnostic tools to prevent these cardiovascular complications in a high risk population in Reunion island. However, no potent tool is available to doctors in order to predict the formation of vulnerable atherosclerotic plaques. Nuclear medicine with its high sensibility could offer new powerful diagnostic tools in order to assess vulnerable atheroma formation. Among all biomarkers available to the scientific community, we chose Lp-PLA2 (Lipoprotein-associated phospholipase A2) which is an enzyme associated to inflammatory processes (produced by monocytes and macrophages) as a target for PET (Positron Emission Tomography) imaging of atherosclerosis.Our work describes the radiolabelling of a potent inhibitor of this enzyme: Darapladib and associated analogs. We were able to perform its radiolabelling and to study its potential accumulation in atheroma murin models and in ex vivo human endarterectomy pieces
Krayem, Maha. "Etude des effets de l'arsenic et du cuivre sur un macrophyte aquatique, Myriophyllum alterniflorum D.C. : évaluation des biomarqueurs pour la détection précoce de pollution." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0131.
Alternate watermilfoil, Myriophyllum alterniflorum is an aquatic macrophyte presented in the rivers of the Limousin region in France whose potential for bioindication of metal pollution has been demonstrated. The objective of this study is to identify in this species sensitive biomarkers for the early detection of pollution in a river by a metal copper, and a metalloid, arsenic. To achieve this goal, a synthetic medium whose composition is representative of the water quality of the river Vienne, was prepared (Vienne medium). The composition of the medium studied is verified by ICP-MS and ion chromatography (IC). The development of the macrophyte was followed in a control medium, a copper contaminated medium and another contaminated with arsenic at a concentration of 100 µg/L for 21 days. During this period, the respiratory and photosynthetic activities of Myriophyllum alterniflorum, the concentrations of chlorophyll a, b and carotenoids, levels of malondialdehyde, osmotic potential, and phytochelatins were recorded. This monitoring has been made in a closed system (400mL culture boxes) taking into account the trophy of the medium (eutrophic and oligotrophic conditions), and then in a recirculating system (aquariums of 150 L) taking into account the hydrodynamic conditions (turbulent, laminar and quiet areas)
Aide, Nicolas. "Médecine nucléaire et tumeurs germinales testiculaires : études précliniques sur l'évaluation thérapeutique précoce et la détection du tératome mature au sein des masses résiduelles après chimiothérapie." Paris 11, 2010. http://www.theses.fr/2010PA11T088.
Billard, Julien. "Contribution à l’identification de facteurs impliqués dans le phénomène de giclage de la bière en vue du développement d’une méthode de détection précoce du « risque giclage »." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0195.
Beer gushing is an explosive over-generation of foam following the opening of a bottle. It is highly dependent on barley growing and harvesting climatic conditions and has been observed more frequently over the past years. Current technics, such as the modified Carlsberg test, only provide informations on a predictive gushing potential of malt with a large uncertainty. A rapid screening test on raw material leading to the identification of actual factor(s) responsible for the gushing is consequently highly required by the brewing industry. But a lack of informations about the compounds involved in gushing limits the development of such a technic. The initial goal of this study was to identify the compounds involved in beer gushing. This approach has been applied to industrial malts presenting gushing potential or not and artificially contaminated barleys in order to set a procedure to isolate compounds which may trigger gushing. In a first time, malt extracts, which are complex mixtures, have been produced and fractionated according to the properties of compounds such as their size, their foaming capacity or hydrophobicity. A good reduction of complexity of sample has been obtained after membrane filtration. Nevertheless, compounds like carbohydrates, proteins and polyphenols could not have been separated. Besides, separation by hydrophobicity has provided good information about the diversity of proteins but the analysis of their gushing potential remains difficult. Afterwards, in order to investigate the production of compounds by fungus at the surface of barley simulating real field crop production conditions, an artificial contamination was achieved and surface extraction with ultrapure water has been performed. Extracted molecules have been screened for their gushing activity. Thus, a purification of molecules by reverse phase chromatography allowed to isolate a gushing fraction from the surface extract. This fraction, which concentrates the gushing properties, is composed by proteins with high hydrophobicity which may be involved in gushing. This fraction was analyzed more in depth with a 2DE, and led to the identification of proteins all produced by fungus family. Among them, a protein called Epl1 appears to be of interest and could be a good candidate thanks its properties closed to hydrophobins (size and hydrophobicity). In conclusion, this methodology is developed to acquire a better knowledge about compounds produced by fungi at the surface of barley as well as to some industrial malt
Boccara, Gilles. "Embolie gazeuse et coelioscopie : détection précoce par doppler transoesophagien et évaluation de l'argon, nouveau gaz effecteur du pneumopéritoine : à propos de 2 études expérimentales chez le porc." Montpellier 1, 1995. http://www.theses.fr/1995MON11112.
Espinoza, Christian. "Approche métabolomique non-ciblée pour révéler les réponses métaboliques des prunus à l'infection par le PPV, conduisant au développement d'un outil de détection innovant pour la détection précoce de la maladie de la sharka et la sauvegarde des vergers en Occitanie." Thesis, Perpignan, 2022. http://www.theses.fr/2022PERP0018.
Sharka disease, caused by Plum pox virus (PPV), is responsible for significant economic losses in Prunus. However, no preventive or curative treatments are currently available and only a few sources of natural resistance have been found. In France, a prophylactic approach has been adopted in an attempt to limit the spread of the PPV, which is essentially based on the rapid detection and removal of infected trees. However, certain technical and economic limitations do not allow the early andeffective detection of PPV on a large scale by conventional methods. The department of Pyrénées Orientales (France) is the most affected by this disease (85% of infections). These issues motivated the creation of the Antishark project, which is the result of a collaboration between AkiNaO, the University of Perpignan Via Domitia, FDGDON66 and local producers. The objective of the project was to develop an innovative method of early detection, targeting the metabolic responses of Prunuspersica at an early stage of the infection. Consequently, two studies under monitored conditions using an untargeted metabolomics approach (UHPLC-HRMS) were carried out. This approach is a promising tool to reveal the metabolic interactions between PPV and its host. In a first study, the global metabolic response to PPV-infection (Dideron and Marcus strains), including symptomatic and asymptomatic leaves, allowed the discrimination of metabolic profiles from PPV-infected and healthy leaves. Although there was a common response between the two strains, metabolic differences were also revealed, notably highlighting strain-specific metabolic alterations. In fact, this novel result could eventually lead to the possibility of identifying the viral strain(s) responsible for the infection. Furthermore, it was possible to discriminate PPV-infected plants (symptomatic and asymptomatic leaves) from healthy plants and from plants infected by another plant pathogenic virus. These observations suggest the existence of a potential specific response to the sharka disease. Based on all these findings, the hypothesis that asymptomatic PPVinfected trees could be detected through virus-induced metabolic alterations is supported.Furthermore, the metabolic responses collected from asymptomatic leaves could be considered as early responses to PPV-infection, i.e., before the appearance of symptoms. In a second step, early metabolic alterations, before the appearance of sharka symptoms, were confirmed by a kinetic study, despite negative molecular tests (RT-qPCR). Our results indicate that early detection of PPVinfected plants by targeting metabolic responses in Prunus persica was a promising strategy. Finally,statistical correlations between the two studies were found. Although the cultivars showed significantly different metabolic profiles, some discriminant features were common between the different cultivars tested (GF-305, yellow nectarine, yellow peach) and also between the different stages of the virus infection (symptomatic and asymptomatic). Nevertheless, a co-infection of PPV and powdery mildew observed during the kinetic experiment under monitored conditions could alter the impact of PPV-infection. Consequently, a new kinetic study without co-infection, is ongoing to confirm or refute these first observations. In addition, the identification of biomarkers related to the sharka disease, also in progress, would provide a betterunderstanding of the metabolic interactions between peach and PPV. Finally, other experiments under natural conditions are underway to evaluate the robustness of our potential biomarkers
Su'ud, Mazliham Bin Mohd. "Conception d'un système d'aide à la décision à partir de données ponctuelles et imparfaites : application à la détection précoce de l'infection du palmier à huile par Ganoderma Fungus." La Rochelle, 2008. http://www.theses.fr/2008LAROS235.
Limitation in accessibility and constrain to perform non destruction observation imply difficulties faced by equipments to acquire complete information on the phenomena understudy. Even as the sensors have become increasingly reliable and accurate, their miniaturization (hand held) or their deployment in a hostile environment (signal reception quality, acquisition condition, etc. . . ) implies significant imperfection in the acquired data. The imperfection of the data is expressed classically in term of imprecision, inconsistency, uncertainty and incompleteness. This work concerns the management of spatially distributed and imperfect data, with the objective of providing assistance to bring the most reliable possible decision, with the constraint of making it legible by a human expert. A Decision Support System based on Human Driven Waterfall Model is proposed to fulfill this requirement. Based on the hierarchisation of data interpolation and observation classification phase, our approach aims to rebuild an estimated non attainable 2D image. The loss of information due to these first few phases is later compensated by the possibility of injecting relevant expert knowledge modeled using a Fuzzy Inference System. Our decision making system is based on fusion of evidence using Dempster Shafer combination. After solving the problem of mass initialization and mass combination rules, we propose an adaptive Dempster Shafer combination to combine regional information from the image. In the second phase of this work, the study is then applied in a quasi non invasive diagnostic of tree health problems near the lower trunk in oil palm plantations in Malaysia. The palm oil industries in Malaysia, which is the main palm oil exporter in the world, is severely affected by the infection. Our approach consists of the internal cartography estimation of the phyto-sanitary state of a cross section of the trunk understudy. From the sonic tomography image which provides some measurement points, we produce a sound image representing the modifications of structural and density of the stem. An image processing technique together with a fuzzy inference system is used to integrate experts knowledge on the low information level image. Our approach was validated by in situ experiments using a prototype designed at the laboratory and validated by Malaysian Palm Oil Board; this prototype allows an expert to estimate in a more objective way the health condition of the Ganoderma infected trees
Vialatte, François Benoît. "Modélisation en bosses pour l'analyse de motifs oscillatoires reproductibles dans l'activité de populations neuronales: applications à l'apprentissage olfactif chez l'animal et à la détection précoce de la maladie d'Alzheimer." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2005. http://pastel.archives-ouvertes.fr/pastel-00001508.
Surini, Thibaud. "Analyse dynamique de la biodégradation du bois et des composites à base de bois et fibres végétales." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13848/document.
Wood biodegradation is studied in order to understand and quantify the mechanical damage. Wood, and especially maritime pine, is sensitive to a fungal attack that causes a decrease of its strength (compression or fracture resistance), before a weight loss occurs. This requires developing or ameliorating the tools of early detection, such as NMR relaxometry, in order to detect the appearance of a pathogen in wooden structures that are more and more appreciated. Besides, wooden composites are a good alternative to make the material more durable, and are ecologically interesting, as they permit to recycle some element, like plastics. This “green” effect is of main importance, which implies a development of new ways in wood preservation. This thesis, led in a short as well as in a long term scale, also studies the behaviour of wood, impregnated with anhydrides or oils from a vegetal origin, or even heat-treated wood. Not only mechanics is described, so that many phenomena are explained and perspectives are clarified
Vialatte, François-Benoît. "Modélisation en bosse pour l'analyse des motifs oscillatoires reproductibles dans l'activité de populations neuronales : applications à l'apprentissage olfactif chez l'animal et à la détection précoce de la maladie d' Alzheimer." Paris 6, 2005. https://pastel.archives-ouvertes.fr/pastel-00001508.