Thèse Médecine Paris, 1836 numéro 376.

Thèse d'exercice : Chirurgie dentaire : Université de Nantes : 2005. / Bibliogr. [23] f. [251 réf.].

Thèses (M.Sc.)--Université de Sherbrooke (Canada), 2001. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.

Middleboxes, such as firewalls, Network Address Translators (NATs), Wide Area Network (WAN) optimizers, or Deep Packet Inspector (DPIs), are widely deployed in modern networks to improve network security and performance. Traditional middleboxes are typically hardware based, which are expensive and closed systems with little extensibility. Furthermore, they are developed by different vendors and deployed as standalone devices with little scalability. As the development of networks in scale, the limitations of traditional middleboxes bring great challenges in middlebox deployments. Network Function Virtualization (NFV) technology provides a promising alternative, which enables flexible deployment of middleboxes, as virtual machines (VMs) running on standard servers. However, the flexibility also creates a challenge for efficiently placing such middleboxes, due to the availability of multiple hosting servers, capabilities of middleboxes to change traffic volumes, and dependency between middleboxes. In our first two work, we addressed the optimal placement challenge of NFV middleboxes by considering middlebox traffic changing effects and dependency relations. Since each VM has only a limited processing capacity restricted by its available resources, multiple instances of the same function are necessary in an NFV network. Thus, routing in an NFV network is also a challenge to determine not only via a path from the source to destination but also the service (middlebox) locations. Furthermore, the challenge is complicated by the traffic changing effects of NFV services and dependency relations between them. In our third work, we studied how to efficiently route a flow to receive services in an NFV network. We conducted large-scale simulations to evaluate our proposed solutions, and also implemented a Software-Defined Networking (SDN) based prototype to validate the solutions in realistic environments. Extensive simulation and experiment results have been fully demonstrated the effectiveness of our design.

Thèse d'exercice : Médecine. Biologie médicale : Université de Nantes : 2005. / Bibliogr. f. 115-123.

Thèse (Ph. D.)--Université Laval, 2002. / Bibliogr. Publié aussi en version électronique.

Texte remanié de: Thèse de doctorat--Lettres--Taipei, 2002. / Mention parallèle de titre ou de responsabilité : The @study of sacrificial inscriptions on the Fourth period oracle bone of the Shang dynasty. Bibliogr. p. [359]-375. Index.

Leber’s Hereditary Optic Neuropathy (LHON) is a devastating mitochondrial disorder that leads to irreversible blindness. A mutation in the mitochondrial ND4 gene causes the majority of cases. Oxidative stress plays a role in disease pathology. WN1316 is a small molecule compound with potent anti-oxidant properties. Using in vitro and in vivo assays, the effectiveness of WN1316 in the treatment of LHON was tested. In vitro, the neuroprotective effects of WN1316 were tested against the oxidative stressors menadione and H2O2. These studies showed that WN1316 can protect SH-SY5Y neuronal cells and 661W photoreceptor-derived cells from oxidative stress in a concentration-dependent manner. Combination therapies with WN1316 and the X-linked Inhibitor of Apoptosis (XIAP) provided even better protection. In vivo, LHON disease had not progressed sufficiently to assess WN1316 effects on retinal function and axon counts. However we saw some delay in disease progression in the WN1316 group using electron microscopy. These initial studies suggest that WN1316 will be effective in the treatment of LHON, but we need to increase the timeline for disease progression to see the full effects of the compound.

Proliferation of new computing hardware platforms that support increasing numbers of cores, as well as increasing ISA heterogeneity, is creating opportunity for systems software developers to question existing software architecture. One promising emerging systems architecture is the multikernel, pioneered in Barrelfish OS. The multikernel directly addresses the challenges of high core counts and increased heterogeneity by partitioning the system into multiple independently running kernel instances which cooperate to form a single operating system. Popcorn Linux is an adaptation of the multikernel concept to a Linux environment, melding the multikernel concept with the power and ubiquity of the Linux platform. The goal of the Popcorn Linux project is to provide a Linux-based single-system image environment for heterogeneous hardware. In constructing this environment, Linux must be extended to distribute the plethora of operating system services that it provides across kernel instances. This thesis presents the newly developed Popcorn Linux mechanism for migrating tasks and their address spaces between kernel instances at arbitrary points in their execution. Both process and thread migration is supported, and distributed address spaces are maintained and guaranteed to remain consistent between distributed thread group members running on different kernel instances. Tasks can migrate through an unlimited number of kernel instances, as well as back to previously visited kernel instances. Additionally, the full task life-cycle is supported, allowing migrated tasks to exit and create new children on whichever kernel instance happens to be hosting them. The mechanisms developed were vetted through unit testing, review, and a number of compute-bound benchmarks in a homogeneous x86 64bit environment. Correctness was demonstrated, and performance metrics were acquired. Popcorn Linux performance was shown to be reasonable when compared to SMP Linux. The mechanisms developed are therefore deemed feasible. Scalability was determined to be a function of workload characteristics, where in some cases Popcorn Linux out-scales SMP Linux and in other cases SMP Linux out-scales Popcorn Linux. Optimizations are recommended to reduce the maturity gap between Popcorn Linux and SMP Linux, improving Popcorn Linux performance. / Master of Science

Thèse d'exercice : Médecine. Chirurgie orthopédique et traumatologique : Université de Nantes : 2005. / Bibliogr. f. 43-47 [35 réf.].