Tesis sobre el tema "Cheval de Troie matériel"
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Ba, Papa-Sidy. "Détection et prévention de Cheval de Troie Matériel (CTM) par des méthodes Orientées Test Logique". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT271/document.
Texto completoIn order to reduce the production costs of integrated circuits (ICs), outsourcing the fabrication process has become a major trend in the Integrated Circuits (ICs) industry. As an inevitable unwanted side effect, this outsourcing business model increases threats to hardware products. This process raises the issue of un-trusted foundries in which, circuit descriptions can be manipulated with the aim to possibly insert malicious circuitry or alterations, referred to as Hardware Trojan Horses (HTHs). This motivates semiconductor industries and researchers to study and investigate solutions for detecting during testing and prevent during fabrication, HTH insertion.However, considering the stealthy nature of HTs, it is quite impossible to detect them with conventional testing or even with random patterns. This motivates us to make some contributions in this thesis by proposing solutions to detect and prevent HTH after fabrication (during testing).The proposed methods help to detect HTH as well during testing as during normal mode(run-time), and they are logic testing based.Furthermore, we propose prevention methods, which are also logic testing based, in order tomake harder or quasi impossible the insertion of HTH both in netlist and layout levels
Díaz, Rizo Alán Rodrigo. "Security and Trust for Wireless Integrated Circuits". Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS005.
Texto completoThe origin of the hardware security threats is the massively globalized and outsourcing-based Integrated Circuit (IC) supply chain that we see today. The prohibitively cost of owning a first-rate semiconductor foundry forces IC design houses to go fabless and outsource their IC fabrication, assembly, and testing. Outsourcing these tasks intensifies the risk of IC piracy attacks and Hardware Trojan (HT) insertion, and both threats translate into know-how and financial losses for the IC owner. Moreover, complex Systems-on-Chip (SoCs) are built by integrating third-party Intellectual Property (IP) cores from multiple IP providers. However, SoC integrators and IP providers have an imbalanced trust relationship. While IP providers are vulnerable to IP overuse, IP cloning, and IC overproduction, SoC integrators fear integrating HT-infected IPs into their systems. We propose a locking-based design-for-security methodology. In addition, we develop an RF transceiver-specific locking methodology that consists in two spatially separated mechanisms. inserting a locking mechanism into the circuit that unlocks with a single secret key in the form of a digital word. To assess the security of wireless ICs, we propose an HT attack that leaks sensitive information from the transmitter within a legitimate transmission
Courbon, Franck. "Rétro-conception matérielle partielle appliquée à l'injection ciblée de fautes laser et à la détection efficace de Chevaux de Troie Matériels". Thesis, Saint-Etienne, EMSE, 2015. http://www.theses.fr/2015EMSE0788/document.
Texto completoThe work described in this thesis covers an integrated circuit characterization methodology based on a partial hardware reverse engineering. On one hand in order to improve integrated circuit security characterization, on the other hand in order to detect the presence of Hardware Trojans. Our approach is said partial as it is only based on a single hardware layer of the component and also because it does not aim to recreate a schematic or functional description of the whole circuit. A low cost, fast and efficient reverse engineering methodology is proposed. The latter enables to get a global image of the circuit where only transistor's active regions are visible. It thus allows localizing every standard cell. The implementation of this methodology is applied over different secure devices. The obtained image according to the methodology declined earlier is processed in order to spatially localize sensible standard cells, nay critical in terms of security. Once these cells identified, we characterize the laser effect over different location of these standard cells and we show the possibility with the help of laser fault injection the value they contain. The technique is novel as it validates the fault model over a complex gate in 90nm technology node.Finally, a Hardware Trojan detection method is proposed using the partial reverse engineering output. We highlight the addition of few non listed cells with the application on a couple of circuits. The method implementation therefore permits to detect, without full reverse-engineering (and so cheaply), quickly and efficiently the presence of Hardware Trojans
Cozzi, Maxime. "Infrared Imaging for Integrated Circuit Trust and Hardware Security". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS046.
Texto completoThe generalization of integrated circuits and more generally electronics to everyday life systems (military, finance, health, etc) rises the question about their security. Today, the integrity of such circuits relies on a large panel of known attacks for which countermeasures have been developed. Hence, the search of new vulnerabilities represents one of the largest contribution to hardware security. The always rising complexity of dies leads to larger silicon surfaces.Circuit imaging is therefore a popular step among the hardware security community in order to identify regions of interest within the die. In this objective, the work presented here proposes new methodologies for infrared circuit imaging. In particular, it is demonstrated that statistical measurement analysis can be performed for automated localization of active areas in an integrated circuit.Also, a new methodology allowing efficient statistical infrared image comparison is proposed. Finally, all results are acquired using a cost efficient infrared measurement platform that allows the investigation of weak electrical source, detecting power consumption as low as 200 µW
Sansiaume, Elodie. "Conception et élaboration de nouvelles métalloenzymes artificielles selon la stratégie du cheval de Troie". Paris 11, 2010. http://www.theses.fr/2010PA112237.
Texto completoThe construction of artificial métalloenzymes has appeared to be one of the most promising strategies explored to induce stereoselectivity into chemical reactions. New metalloporphyrin-estradiol conjugates and testosterone conjugates have been synthesized and fully characterized, and have been further associated respectively to a monoclonal anti-estradiol antibody 7A3 and neocarzinostatin's mutants, to generate new artificial metalloenzymes following the so-called 'Trojan Horse' strategy. The spectroscopic characteristics and dissociation constants of these complexes were similar to those obtained for the artificial metalloproteins obtained by association of cationic metalloporphyrin-estradiol conjugates to 7A3. This demonstrates that the nature of the porphyrin substituents, anionic or cationic, had little influence on the association with the antibody that is mainly driven by the tight association of the estradiol anchor with the binding pocket of the antibody. These new biocatalysts appeared to have an interesting catalytic activity in oxidation reactions. The iron(III)-anionic-porphyrin-estradiol-antibody complexes and the iron(III)-anionic-porphyrin-testosterone-neocarzinostatine's mutants complexes were found able to catalyze the chemoselective and slightly enantioselective (ee = 10 % et 24 % à 40 % respectively) sulfoxidation of sulfides by H202. The Mn(III)-porphyrin-estradiol antibody complexes were found to catalyze the oxidation of styrene by KHSO5, the Mn(III)-cationic-porphyrin-estradiol-antibody complexes even showing the highest yields so far reported for the oxidation of styrene catalyzed by artificial metalloproteins
Exurville, Ingrid. "Détection non destructive de modification malveillante de circuits intégrés". Thesis, Saint-Etienne, EMSE, 2015. http://www.theses.fr/2015EMSE0800/document.
Texto completoThe globalization of integrated circuits fabrication involves several questions about the integrity of the fabricated circuits. Malicious modifications called Hardware Trojans (HT) can be introduced during the circuit production process. Due to the complexity of an integrated circuit, it is really difficult to find this kind of alterations.This work focuses on a non-destructive method of HT detection. We use the paths delays of the studied design as a channel to detect HT. A model to describe paths delays is defined. It takes into account two important parameters which are the experimental conditions and the process variations.Faults attacks by clock glitches based on timing constraints violations have been performed to measure data paths delays. Reliable circuits are used for reference. After validating the relevance of this channel to get information on the internal behavior of the targeted design, experimental detections of HT inserted on two different abstraction levels (RTL and after place and route) were achieved. Process variations are taken into consideration in the studies to detect if the tested circuits are infected
Acunha, guimarães Leonel. "Techniques de Test Pour la Détection de Chevaux de Troie Matériels en Circuits Intégrés de Systèmes Sécurisés". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT080/document.
Texto completoThe world globalization has led the semiconductor industry to outsource design and fabrication phases, making integrated circuits (ICs) potentially more vulnerable to malicious modifications at design or fabrication time: the hardware Trojans (HTs). New efficient testing techniques are thus required to disclose potential slight and stealth HTs, and to ensure trusted devices. This thesis studies possible threats and proposes two new post-silicon testing techniques able to detect HTs implanted after the generation of the IC netlist. The first proposed technique exploits bulk built-in current sensors (BBICS) -- which are originally designed to identify transient faults in ICs -- by using them as testing mechanisms that provide statistically-comparable digital signatures of the devices under test. With only 16 IC samples, the testing technique can detect dopant-level Trojans of zero-area overhead. The second proposition is a non-intrusive technique for detection of gate-level HTs in asynchronous circuits. With this technique, neither additional hardware nor alterations on the original test set-up are required to detect Trojans smaller than 1% of the original circuit. The studies and techniques devised in this thesis contribute to reduce the IC vulnerability to HT, reusing testing mechanisms and keeping security features of original devices
Elshamy, Mohamed. "Design for security in mixed analog-digital integrated circuits". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS093.
Texto completoRecently, the enormous cost of owning and maintaining a modern semiconductor manufacturing plant has coerced many companies to go fabless. By outsourcing the manufacturing IC/IP to third-party and often off-shore companies, the process has been extended to potentially untrustworthy companies. This has resulted in several security threats to the semiconductor industry such as counterfeiting, reverse engineering, and HTs insertion. In this thesis, we propose an anti-piracy countermeasure to protect AMS ICs/IPs, a novel HT attack for AMS ICs/IPs, and a novel PUF. More specifically, we propose an anti-piracy technique based on locking for programmable analog circuits. The proposed technique leverages the programmability fabric to implement a natural lock-less locking. We discuss its implementation and its resilience capabilities against foreseen attacks. The proposed HT attack for analog circuits leverages the test infrastructure. The HT is hidden effectively in a digital core and transfers its payload to the analog circuit via the test bus and the interface of the analog circuit to the test bus. Its key characteristic is that it is invisible in the analog domain. The proposed HT is demonstrated on two case studies. This thesis sheds light on the importance of developing new security and trust countermeasures tailored for analog circuits. The proposed PUF, called "neuron-PUF", uses a single spiking neuron as the source of entropy. Its key characteristic is that it uses a single PUF cell and temporal redundancy to generate an arbitrarily long key, which results in significant low area and power overheads compared to mainstream PUFs, such as delay-based and memory-based PUFs
Benhani, El mehdi. "Sécurité des systèmes sur puce complexes hétérogènes". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSES016.
Texto completoThe thesis studies the security of the ARM TrustZone technology in the context of complex heterogeneous SoCs. The thesis presents hardware attacks that affect elements of the SoCs architecture and it also presents countermeasure strategies
Lecomte, Maxime. "Système embarque de mesure de la tension pour la détection de contrefaçons et de chevaux de Troie matériels". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEM018/document.
Texto completoDue to the trend to outsourcing semiconductor manufacturing, the integrity of integrated circuits (ICs) became a hot topic. The two mains threats are hardware Trojan (HT) and counterfeits. The main limit of the integrity verification techniques proposed so far is that the bias, induced by the process variations, restricts their efficiency and practicality. In this thesis we aim to detect HTs and counterfeits in a fully embedded way. To that end we first characterize the impact of malicious insertions on a network of sensors. The measurements are done using a network of Ring oscillators. The malicious adding of logic gates (Hardware Trojan) or the modification of the implementation of a different design (counterfeits) will modify the voltage distribution within the IC.Based on these results we present an on-chip detection method for verifying the integrity of ICs. We propose a novel approach which in practice eliminates this limit of process variation bias by making the assumption that IC infection is done at a lot level. We introduce a new variation model for the performance of CMOS structures. This model is used to create signatures of lots which are independent of the process variations. A new distinguisher has been proposed to evaluate whether an IC is infected. This distinguisher allows automatically setting a decision making threshold that is adapted to the measurement quality and the process variation. The goal of this distinguisher is to reach a 100\% success rate within the set of covered HTs family. All the results have been experientially validated and characterized on a set of FPGA prototyping boards
Paulen, Aurélie. "Utilisation de la stratégie du cheval de Troie pour lutter contre Pseudomonas aeruginosa : synthèses et propriétés biologiques de conjugués sidérophores-antibiotiques". Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ021/document.
Texto completoConstant discovery of innovative therapeutic strategies against pathogenic bacteria is crucial. Iron is essential for bacterial proliferation since it is integrated in the active site of essential enzymes. Many pathogenic bacteria excrete low molecular weight secondary metabolites called siderophores in order to promote iron (III) acquisition. Transmembrane siderophore-dependent iron uptake systems can be used as gates by siderophore-antibiotic conjugates. In this context, we synthesized conjugates between analogs of pyochelin, aminochelin or azotochelin with oxazolidinones antibiotics. In this project many of the conjugation between vectors and antibiotics were the result of click chemistry reactions even the use of peptidic bonds was also explored. Synthesis and biological properties of conjugates and vectors are presented in this manuscript
Cordeau, Françoise. "Le Cheval de Troie (roman) suivi de : L'expression du sentiment d'abandon chez Anne Hébert, Louise Desjardins, Bruno Roy et Björn Larsson". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28293/28293.pdf.
Texto completoReyes, Carillo Tatiana. "L'éco-conception dans les PME : les mécanismes du cheval de Troie méthodologique et du choix de trajectoires comme vecteurs d'intégration de l'environnement en conception". Phd thesis, Université du Sud Toulon Var, 2007. http://tel.archives-ouvertes.fr/tel-00274389.
Texto completoReyes, Carrillo Tatiana. "L'éco-conception dans les PME : les mécanismes du cheval de Troie méthodologique et du choix de trajectoires comme vecteurs d'intégration de l'environnement en conception". Toulon, 2007. http://tel.archives-ouvertes.fr/tel-00274389/fr/.
Texto completoThis research proposes a new solution to fulfill the need to develop an accessible mechanism to implement sustainable design in the long term, based on 2 axes. The first axis relies on the clear identification of integration trajectories. This allows the company to guide the integration process on the long term. The second axis is based on an ecodesign tool that is conceived and developed by all the main participants in the design. This axis enables a progressive evolution of environmental performance within an organization. An investigation work has been done, with specific experts for the first axis and with ecodesign pioneers companies for the second axis. We call this second point mechanism a "methodological Trojan horse" approach ("MTH") because the underlying strategy is to introduce an appropriate pretext that enables collaborative work (the ecodesign tool has to be co-designed) and to supply the organization with the necessary skills to develop the tool at a later stage. The "MTH" approach facilitates the propagation of sustainable design knowledge at all levels within the company and thus allows the company to progress towards complete integration (from a partial sustainable design approach to an eco-innovation approach, integrating the requirements of sustainable development). The whole concept of this MTH was tested over a period of two years in the company Transfix that manufactures transformers. It has successfully highlighted the benefits of this integrated approach based on the "MTH" mechanism and guided by the "ecodesign tools and methods" integration trajectory
Reyes, Carrillo Tatiana Millet Dominique Brissaud Daniel. "L' éco-conception dans les PME les mécanismes du cheval de Troie méthodologique et du choix de trajectoires comme vecteurs d'intégration de l'environnement en conception /". [S.l.] : [s.n.], 2007. http://tel.archives-ouvertes.fr/tel-00274389/fr.
Texto completoBoos, Romain. "La lutte contre la cybercriminalité au regard de l’action des États". Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0158/document.
Texto completoThe twenty-first century sees the consecration of digital technologies just as the end of the Middle-Ages saw the creation of printing.Henceforth, the digital era has no limits. It gives access to culture and knowledge, encourages the exchanges between people.It allows the constitution of an economy online and brings citizens closer to their adminitration. Digital technologies generate innovation and growth, and can help or accelerate the development of the emergent countries as well. But a certain pessimism moderates this idealistic approach.All these advances also generate new fragilities and vulnerabilities propicious to threats or risks, as they stimulate the criminals' imagination.Now , cybercriminality has become reality.It is all the more dangerous as it penetrates within families , where ordinary delinquency didn't exist until now. From now on, this new kind of criminality made it obvious that the judicial system had to be adapted. Indeed , faced with these violations , there are of course laws that are applied here and now to the Internet.But , are they really efficient? In the same way, is the intersate cooperation also sufficient to fight against cybercriminality? So , it is important to wonder whether , in our modern society , the legislative framework and the institutional cooperation , both european and international , are sufficient and efficient to penalize the cybercriminal offences
Madaoui, Mimouna. "Synthèse de conjugués glycoclusters-sidérophores pour augmenter l’activité anti-infectieuse contre Pseudomonas aeruginosa". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS073.
Texto completoThe growth of multidrug resistance is one of the major public health issues of the 21st century. Pseudomonas aeruginosa (PA) ranks among the top five virulent bacterial pathogens. Many strategies have been developed to fight them and among them we investigated the use of glycoclusters to block PA virulence factors leading to the reduction of biofilm, adhesion and internalization. For this goal, we have particularly targeted the two soluble PA lectins: LecA and LecB that recognize specifically D-galactose and L-fucose respectively. Certain glycoclusters are able to decrease the biofilm formation of PAO1 strain and to reduce the internalization of PA in epithelial cells.On other hand, iron play an important role in growth and survival mechanisms in PA. In order to catch this mineral compound, microorganisms produce low molecular weight molecules named siderophores. Fe3+-siderophore complex is transported across membrane by sophisticated active transport. In goal to improve anti-infective activity of glycoclusters, it was imagined to combine glycoclusters with pseudo-siderophores. This «Trojan Horse» strategy could help glycoclusters to cross bacteria membrane and target the lectins that are located there. To this end, we have developed a synthesis strategy based on nucleic acid chemistry and click chemistry starting from simple building blocks. In this thesis, we will present the synthesis of these conjugates and their efficiency to target LecA and LecB
Loupias, Pauline. "Synthèse et étude d'analogues de sidérophores à large spectre antibactérien". Thesis, Amiens, 2020. http://www.theses.fr/2020AMIE0032.
Texto completoThis work consisted in exploiting a new therapeutic strategy to fight Pseudomonas aeruginosa and Burkholderia pseudomallei, two Gram-negative bacteria particularly concerning. While P. aeruginosa, which is part of the ESKAPE bacteria, is responsible for the majority of nosocomial infections, B. pseudomallei, formerly classified in the Pseudomonas group, is involved in Whitmore's disease and is considered by the CDC as a potential bioterrorist weapon. These two pathogens have natural and acquired resistance to many antibiotics by efflux or via a lack of membrane permeability, which makes treatment difficult. Facing this health emergency, the use of the "Trojan Horse" strategy to vectorize antibiotics can help restore their activities. Iron is a micronutrient necessary for the survival of bacteria, but it is not very bioavailable due to its low solubility in water. To acquire it, many bacteria synthesize molecules of low molecular weight, called siderophores, capable of chelating the surrounding iron. The complexes formed are then recognized specifically by TonB-dependent receptors in order to transport iron within bacteria. Depending on their type, bacteria express different receptors recognizing their endogenous siderophores but also xenosiderophores or synthetic siderophores. The use of these different kinds of siderophores to carry an antibiotic or a toxic metal such as gallium into the bacteria has already led to promising results. The objectives of this PhD were to synthesize new siderophores of piperazine structure, new siderophore-antibiotic conjugates and toxic siderophore-gallium complexes. Physico-chemical and biological studies were also carried out in order to validate the interest of the structures chosen in anti-infectious chemotherapy
Al-Sid-Cheikh, Maya. "Impact des oxydes de fer naturels et des nanoparticules manufacturées sur la dynamique des éléments traces dans les sols de zones humides". Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S144.
Texto completoNanoscience is based on changes in particle properties when their diameter is below 100 nm (ie nanoparticles, NPs). Considering the increasing use of such NPs and their discharge into the environment, the assessment of their risks to human health and the environment is a major issue. Underneath the protection of waters and soils, the surface water assessment quality is particularly important, especially in wetlands, where the toxic metals dynamic (e.g. As, Pb, Ni, Cr , Hg) is complex and depends on the redox conditions of the environment. As magnetite (nano-Fe3O4), a natural or manufactured NP, is known for its significant adsorption capacity with heavy metals, their interactions in riparian wetlands with trace metals (TMs) remain critical concerning their direct of indirect impact on trace metals (TMs) mobility. The objective of this thesis was to study the role of manufactured nano-Fe3O4 (~ 10nm) and natural iron oxides on the TMs dynamics in wetland surface waters and soils. Therefore, in a first part considering natural colloidal precipitates from reoxidation products from riparian areas (subject to redox oscillations), a spatial distribution of elements was performed using nanoSIMS isotope mapping (i.e. 75As-, 56Fe16O-, sulfur (32S-) and organic matter (12C14N-), while the sulfur speciation was evaluated X-ray adsorption at K edge of the sulfur (S) (XANES). These analyzes allowed to highlight the interactions between natural iron oxides, natural organic matter (NOM) and a toxic metalloid, As. Our results suggest, with a statistical colocalization of nanoSIMS images, the existence of two interaction types: (1) 12C14N-, 32S-, 56Fe16O- and 75As-, and (2) 12C14N-, 32S- and 75As-. The coexistence of the oxidized and reduced forms of S, confirmed by the XANES analyses might be attributed to the slow oxidation kinetic of MON. Thus, this first part shows that in addition to the known interactions between MON, iron oxides and As, a possible direct interaction between As and NOM through sulfur functional groups (e.g. thiols) are also possible in oxidized environment. In a second part, the effect of nano-Fe3O4 (~ 10 nm) on trace elements (TEs) and colloids mobility in the organomineral horizon of a natural wetland soil was assessed using soil columns. Our results show that the nanoparticles coating influences the mobility of NOM and TMs. Indeed, the TMs mobility increases in presence of naked nano-Fe3O4, suggesting associations where NOM stabilizes the nanoparticles and increase the nanoparticles and associated TMs mobility. This mechanism seems less possible with coated nano-Fe3O4 where MON blocks the coating adsorption sites and therefore the adsorption of metals
Pesset, Bénédicte. "Conception, synthèse et vectorisation d'inhibiteurs potentiels de la protéine bactérienne TonB". Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAJ089/document.
Texto completoThe increasing resistances to the current antibiotherapies, and the potential use of pathogenic bacteria as biological weapons led us to the absolute necessity of discovering new biological targets and new antibiotic strategies. In this context, iron uptake pathways of Gram negative bacteria are promising targets. Indeed, iron is an essential nutrient, but it has a low bioavailability. Bacteria have developed efficient iron uptake pathways in order to proliferate. Iron is transported in the bacterial cell by specific outer membrane transporters and thanks to the energy provided by a complex molecular machinery, called TonB. The TonB protein, which is the keystone of this machinery, is a key target for the development of new antibiotics. We would like to sequester this protein in the periplasm thanks to molecules constituted of a peptidic moiety and a heterocyclic moiety such as isoindole or 1,2,4-triazine. The conception and the synthesis of these compounds are presented in this document, as well as their possibilities to be vectorized using a “Trojan Horse” strategy. Our contribution to the development of an in vitro test of affinity is presented as well
Baillif, Christele. "La pratique de la monte à cheval au haut Moyen Age (fin V - VII siècle) dans le nord-est de la Gaule. : Εtat des cοnnaissances archéοlοgiques, recherche méthοdοlοgique sur le "syndrοme du cavalier" et applicatiοn d'un nοuveau prοtοcοle d'étude aux pοpulatiοns mérοvingiennes". Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC021/document.
Texto completoThe topic of the equestrian practice of Western archaeological populations often leads to the question of the use of stirrups or not ? This question on the absence or presence of the stirrup in the ancient times is closely related to L. T. White's thought about his introduction to the West. He qualifies the character of this equestrian object as "revolutionary". This element of the equestrian equipment does not favor a better control of the animal, as you can be an excellent rider without stirrups like North American Indians during the colonial period. The stirrup or the stirrups offer new points of support to the rider and undeniably modify his posture on the horse. The posture of the rider has been the subject of many attentions as shown by the ancient, modern and current equestrian treaties. A large group of occupational stress markers described, by anthropological studies, and known with the term "horse-riding syndrome" would make it possible to recognize bone lesions associated with this equestrian activity. The rider’s change of position on the horse, especially during the introduction of new equestrian equipment such as the stirrup, raises the question of the universality of this syndrome regardless of the chronological period studied : a Greek rider does not have the same equestrian equipment as a rider of the 18th century. Therefore, both do not position themselves in the same way on their equine partner. The new study of this syndrome has helped to emphasizing the importance of conducting interdisciplinary research (using horse archeology, biological anthropology and equestrian sport medicine data) in order to rigorously discuss the injury impact of this activity on the rider's body as well as the influence of the equipment used. The Merovingian period offers an ideal archaeological context for such a study because of the presence of both equestrian artifacts and stirrup from the end of the 6th century in the burials, helping in defining occupational stress markers of this equestrian activity, and identifying riders, within the Merovingian funerary groups
Martinez, Alvarez Ignacio. "Les nanomatériaux comme porteurs des polluants organiques persistants : évaluation des risques pour l'environnement aquatique basée sur l’étude d’un petit invertébré et d’un poisson modèle". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0332.
Texto completoPresence and effects of micro- (< 5mm) and nanomaterials (<100 nm, NM) in the environment are a current issue of concern. Aquatic ecosystems with high pollution pressure already present a cocktail of chemicals, where micro- and NMs can act as sponges for these pollutants due to their high surface to volume ratio and hydrophobic surface. This phenomenon can alter the bioavailability of the pollutants present in the aquatic ecosystem, especially for hydrophobic compounds and, therefore, modulate their toxicity to aquatic organisms. Therefore, in the present Thesis the following objectives were established: (1) To assess the potential bioavailability and toxicity of polystyrene nanoplastics (NPs), and of microplastics (MPs) alone and with sorbed polycyclic aromatic hydrocarbons (PAHs) to brine shrimp larvae and zebrafish; (2) To determine sorption capacity of PAHs to MPs and graphene oxide NMs (GNMs); (3) To assess the potential bioavailability and toxicity of GNMs alone and with sorbed PAHs to zebrafish.Exposure to pristine MPs did not cause any significant impact on brine shrimp larvae and zebrafish embryo survival, while some treatments containing elevated concentrations (mg/L) of MPs with sorbed benzo(a)pyrene (B(a)P) and B(a)P alone resulted in acute toxicity. In addition, both sizes of MPs were successful vectors of B(a)P to brine shrimp and zebrafish embryos. Results indicated that small MPs (0.5 µm) showed higher maximum sorption capacity for B(a)P than larger MPs (4.5 µm). In the case of a complex and environmentally relevant PAH mixture, as that formed in the water accommodated fraction (WAF) of a crude oil, a relatively limited sorption to 4.5 µm MPs, driven by the hydrophobicity and initial concentration of each PAH, was observed. In adult zebrafish, MPs did not act as PAH vehicle after 21-day exposure to MPs with sorbed PAHs. Only fish exposed to MPs for 21 days presented changes in the transcription level of biotransformation metabolism-related gene cyp1a in the liver, along with a significant increase in the prevalence of liver vacuolisation. 21 days of exposure to NPs, but not to MPs, caused oxidative stress in adult zebrafish. Ingestion of NPs was observed in the developing organisms (brine shrimp and zebrafish). In embryos, fluorescent NPs were specially localised in the eyes, yolk sac and tail, showing their capacity to translocate and spread into the embryo body.For GNMs, graphene oxide (GO) showed a higher sorption capacity for B(a)P than MPs. For the PAH mixture of the WAF, sorption to GO was also higher than to MPs. In embryos exposed to different GNMs alone and with PAHs, no significant mortality was recorded for any treatment. Nevertheless, malformation rate increased significantly in embryos exposed to the highest concentrations (5 or 10 mg/L) of GO, reduced GO alone and with sorbed B(a)P. According to chemical analysis of adult fish tissues, bioavailability of PAH sorbed to GO for fish was lower than in the case of PAHs alone. Only biochemical responses and genes related to biotransformation metabolism were altered in the liver of fish exposed to B(a)P for 3 days. Transcription level of genes related to oxidative stress were not altered. On the contrary, the gills of fish exposed to GO with sorbed B(a)P and to B(a)P for 3 days and co-exposed to GO and WAF for 21 days showed significantly higher oxidative stress than control fish. A common neurotoxic effect was caused in all fish treated for 21 days. Finally, adult fish exposed to GO presented GO ingestion and liver vacuolisation, but absence of GO translocation to the adult tissue was reported. The present work shows evidences of the capacity of MPs with sorbed PAHs to cause sublethal effects (1) and to carry PAHs (2) in brine shrimp and zebrafish. Finally, GO was greater carrier of PAHs to zebrafish than MPs (3) due to its higher sorption capacity (2), exerting oxidative stress and neurotoxicity as the main sublethal effects in adult zebrafish
La presencia y los efectos de micro- (<5 mm) y nanomateriales (100 nm, NM) en el medio ambiente es un tema de preocupación actual. En sistemas acuáticos que presentan un coctel de químicos debido a la alta presión de la contaminación, los micro- y NMs pueden actuar como esponjas para los contaminantes debido a su alto ratio superficie/volumen y a la hidrofobicidad de su superficie. Este fenómeno puede alterar la biodisponibilidad de los contaminantes presentes en los ecosistemas acuáticos, especialmente para los compuestos hidrófobos, y seguidamente, modular su toxicidad para los organismos acuáticos. Por ello, en la presente tesis los siguientes objetivos fueron establecidos: (1) Evaluar la biodisponibilidad y la toxicidad potencial de nanoplásticos de poliestireno (NPs), y de microplásticos (MPs) solos o con hidrocarburos aromáticos policíclicos ad/absorbidos (HAPs) para la larva de Artemia y el pez cebra; (2) Determinar la capacidad de ad/absorción de HAPs por los MPs y los NMs de óxido de grafeno (GNMs); (3) Evaluar la biodisponibilidad y toxicidad de GNMs solos o con HAPs ad/absorbidos para el pez cebra.La exposición a MPs prístinos no causó ningún impacto significativo en la supervivencia de la larva de Artemia o del embrión de pez cebra, mientras que algunos tratamientos que contenían elevadas concentraciones (mg/L) de MPs con benzo(a)pireno (B(a)P) ad/absorbido y B(a)P sólo resultaron en toxicidad aguda. Además, ambos tamaños de MPs fueron exitosos vectores de B(a)P en larvas de Artemia y embriones de pez cebra. Los resultados indicaron que los MPs pequeños (0.5 μm) mostraron una mayor capacidad máxima de ad/absorción de B(a)P que los MPs grandes (4.5 μm MPs). Para una mezcla compleja y medioambientalmente relevante de HAPs, como es la formada en la fracción acomodada al agua (WAF) de un petróleo crudo, se observó una ad/absorción limitada relativamente a 4.5 μm MPs y que dependió de la hidrofobicidad y la concentración inicial de cada HAP. En adultos de pez cebra, los MPs no actuaron como vehículos de HAP después de 21 días de exposición a MPs con HAPs ad/absorbidos. Solo aquellos peces expuestos a MPs durante 21 días presentaron cambios en los niveles de transcripción del gen cyp1a relacionado con el metabolismo de biotransformación en el hígado, junto con un aumento significativo de la prevalencia de la vacuolización del hígado. 21 días de exposición a NPs, pero no a MPs, causó un estrés oxidativo en los adultos de pez cebra. La ingestión de NPs se observó en los organismos en desarrollo (Artemia y pez cebra). En embriones, los NPs fluorescentes se localizaron específicamente en los ojos, saco vitelino y cola, mostrando la capacidad de los mismos para ser internalizados y repartidos en el interior del cuerpo del embrión.Para los GNMs, el óxido de grafeno (GO) presentó una mayor capacidad de ad/absorción de B(a)P que los MPs. Para la mezcla de HAPs del WAF, la ad/absorcíon a GO fue de nuevo mayor que para los MPs. Para los embriones expuestos a diferentes GNMs solos y con HAPs no se obtuvo una mortalidad significativa. Aun así, el ratio de malformaciones aumento significativamente en embriones expuestos a las concentraciones más altas (5 o 10 mg/L) de GO, GO reducido solo o con B(a)P ad/absorbido. De acuerdo con los ensayos químicos en el tejido de pez adulto, la biodisponibilidad de HAP ad/absorbidos a GO para peces fue menor que en los peces expuestos a HAPs solos. Solo se vieron alteradas las respuestas bioquímicas y los genes relacionados con el metabolismo de biotransformación en hígado de pez expuesto a B(a)P durante 3 días. [...]
Vermeys, Nicolas. "La responsabilité civile des intermédiaires ayant participé à la transmission de virus informatiques sur Internet". Thèse, 2002. http://hdl.handle.net/1866/15127.
Texto completoNivine, Alnaga. "Synthèse de la Quinolobactine, de l'Entérobactine et leurs dérivés. Etudes de la complexation du fer". Phd thesis, 2007. http://tel.archives-ouvertes.fr/tel-00405713.
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