Adaptive Privacy Management System Design For Context-Aware Mobile Devices

While mobile technologies can provide great personalized services for mobile users, they also threaten their privacy. Such personalization-privacy paradox are particularly salient for context aware technology based mobile applications where user's behaviors, movement and habits can be associated with a consumer's personal identity. In this thesis, I studied the privacy issues in the mobile context, particularly focus on an adaptive privacy management system design for context-aware mobile devices, and explore the role of personalization and control over user's personal data. This allowed me to make multiple contributions, both theoretical and practical. In the theoretical world, I propose and prototype an adaptive Single-Sign On solution that use user's context information to protect user's private information for smartphone. To validate this solution, I first proved that user's context is a unique user identifier and context awareness technology can increase user's perceived ease of use of the system and service provider's authentication security. I then followed a design science research paradigm and implemented this solution into a mobile application called "Privacy Manager". I evaluated the utility by several focus group interviews, and overall the proposed solution fulfilled the expected function and users expressed their intentions to use this application. To better understand the personalization-privacy paradox, I built on the theoretical foundations of privacy calculus and technology acceptance model to conceptualize the theory of users' mobile privacy management. I also examined the role of personalization and control ability on my model and how these two elements interact with privacy calculus and mobile technology model. In the practical realm, this thesis contributes to the understanding of the tradeoff between the benefit of personalized services and user's privacy concerns it may cause. By pointing out new opportunities to rethink how user's context information can protect private data, it also suggests new elements for privacy related business models.

System-level Support for Mobile Ad hoc Communications: an Algorithmic & Practical Approach

A mobile ad hoc network (MANET) is a decentralized and infrastructure-less network. This thesis aims to provide support at the system-level for developers of applications or protocols in such networks. To do this, we propose contributions in both the algorithmic realm and in the practical realm. In the algorithmic realm, we contribute to the field by proposing different context-aware broadcast and multicast algorithms in MANETs, namely six-shot broadcast, six-shot multicast, PLAN-B and ageneric algorithmic approach to optimize the power consumption of existing algorithms. For each algorithm we propose, we compare it to existing algorithms that are either probabilistic or context-aware, and then we evaluate their performance based on simulations. We demonstrate that in some cases, context-aware information, such as location or signal-strength, can improve the effciency. In the practical realm, we propose a testbed framework, namely ManetLab, to implement and to deploy MANET-specific protocols, and to evaluate their performance. This testbed framework aims to increase the accuracy of performance evaluation compared to simulations, while keeping the ease of use offered by the simulators to reproduce a performance evaluation. By evaluating the performance of different probabilistic algorithms with ManetLab, we observe that both simulations and testbeds should be used in a complementary way. In addition to the above original contributions, we also provide two surveys about system-level support for ad hoc communications in order to establish a state of the art. The first is about existing broadcast algorithms and the second is about existing middleware solutions and the way they deal with privacy and especially with location privacy. - Un réseau mobile ad hoc (MANET) est un réseau avec une architecture décentralisée et sans infrastructure. Cette thèse vise à fournir un support adéquat, au niveau système, aux développeurs d'applications ou de protocoles dans de tels réseaux. Dans ce but, nous proposons des contributions à la fois dans le domaine de l'algorithmique et dans celui de la pratique. Nous contribuons au domaine algorithmique en proposant différents algorithmes de diffusion dans les MANETs, algorithmes qui sont sensibles au contexte, à savoir six-shot broadcast,six-shot multicast, PLAN-B ainsi qu'une approche générique permettant d'optimiser la consommation d'énergie de ces algorithmes. Pour chaque algorithme que nous proposons, nous le comparons à des algorithmes existants qui sont soit probabilistes, soit sensibles au contexte, puis nous évaluons leurs performances sur la base de simulations. Nous montrons que, dans certains cas, des informations liées au contexte, telles que la localisation ou l'intensité du signal, peuvent améliorer l'efficience de ces algorithmes. Sur le plan pratique, nous proposons une plateforme logicielle pour la création de bancs d'essai, intitulé ManetLab, permettant d'implémenter, et de déployer des protocoles spécifiques aux MANETs, de sorte à évaluer leur performance. Cet outil logiciel vise à accroître la précision desévaluations de performance comparativement à celles fournies par des simulations, tout en conservant la facilité d'utilisation offerte par les simulateurs pour reproduire uneévaluation de performance. En évaluant les performances de différents algorithmes probabilistes avec ManetLab, nous observons que simulateurs et bancs d'essai doivent être utilisés de manière complémentaire. En plus de ces contributions principales, nous fournissons également deux états de l'art au sujet du support nécessaire pour les communications ad hoc. Le premier porte sur les algorithmes de diffusion existants et le second sur les solutions de type middleware existantes et la façon dont elles traitent de la confidentialité, en particulier celle de la localisation.

Ambulatory gait analysis results after total knee arthroplasty : arguments for mobile or fixed bearing?

Background: Mobile-bearing knee replacements have some theoretical advantages over fixed-bearing devices. However, very few randomized controlled clinical trials have been published to date, and studies showed little clinical and subjective advantages for the mobile-bearing using traditional systems of scoring. The choice of the ideal outcome measure to assess total joint replacement remains a complex issue. However, gait analysis provides objective and quantifying evidences of treatment evaluation. Significant methodological advances are currently made in gait analysis laboratories and ambulatory gait devices are now available. The goal of this study was to provide gait parameters as a new objective method to assess total knee arthroplasty outcome between patients with fixed- and mobile-bearing, using an ambulatory device with minimal sensor configuration. Methods: This randomized controlled double-blind study included to date 31 patients: the gait signatures of 12 patients with mobile-bearing were compared to the gait signatures of 19 patients with fixed-bearing pre-operatively and post-operatively at 6 weeks, 3 months and 6 months. Each participant was asked to perform two walking trials of 30m long at his/her preferred speed and to complete a EQ-5D questionnaire, a WOMAC and Knee Society Score (KSS). Lower limbs rotations were measured by four miniature angular rate sensors mounted respectively, on each shank and thigh. Results: Better relative differences between pre-operative and post-operative 3 months and 6 months KSS (122% vs 34% at 3 months, 138% vs 36% at 6 months) and KSS function (154% vs 8% at 3 months, 183% vs 42% at 6 months) scores were observed for the fixed-bearing compared to the mobile-bearing. The same better improvements for fixed-bearing were also found with the range of knee angles (Affected side: 31% vs -5% at 3 months, 47% vs 5% at 6 months), (Unaffected side: 16% vs 5% at 3 months, 15% vs 6% at 6 months) and peak swing speeds of shank (Affected side: 18% vs -2% at 3 months, 30% vs 4% at 6 months), (Unaffected side: 8% vs -3% at 3 months, 7% vs 4% at 6 months). Conclusions: A new method for a portable system for gait analysis has been developed with very encouraging results regarding the objective outcome of total knee arthroplasty using mobile- and fixed-bearings.

Organisation des secours extrahospitaliers lors du sommet 2003 du G8: nouveau concept de poste médical mobile (PMM) [Prehospital medical care organization during the 2003 G8 summit: a new concept of Mobile Medical Squadrons (MMS)].

OBJECTIVE: The occurrence of the 2003 G8 summit in Evian and the threat of major civil riots or even terrorist attacks in the Swiss neighbourhood forced us to imagine a new system of rescue and medical care in case of numerous victims. Previous occurrences of the G8 in Europe or America have demonstrated the need of flexible and mobile structures, able to respond quickly to crowd movements, unlike the usual static structure of rescue systems designed for major accidents. METHODS: We developed a new concept of Mobile Medical Squadrons (MMS) consisting of several vehicles and medical care and rescue human resources. In our concept, each MMS consisted of 3 emergency doctors, 5 paramedics and 9 first-aid workers. They were designed to handle 15 patients, with a large autonomy in terms of rescue, medical care, evacuation and medical authority. The equipment included medical, resuscitation, simple decontamination, evacuation and communication materials. RESULTS: The MMS were dispatched four times during the G8 summit following civil riots. They took care of 12 injured patients. CONCLUSION: The concept of MMS as a reinforcement of the existing rescue and health care resources appears as a new flexible, a modular and useful concept for the medical management of collective prehospital emergency situations. Its use is suggested instead of the traditional static concept of rescue systems designed for major accidents.

The ubiquitin-proteasome system and signal transduction pathways regulating Epithelial Mesenchymal transition of cancer.

Epithelial to Mesenchymal transition (EMT) in cancer, a process permitting cancer cells to become mobile and metastatic, has a signaling hardwire forged from development. Multiple signaling pathways that regulate carcinogenesis enabling characteristics in neoplastic cells such as proliferation, resistance to apoptosis and angiogenesis are also the main players in EMT. These pathways, as almost all cellular processes, are in their turn regulated by ubiquitination and the Ubiquitin-Proteasome System (UPS). Ubiquitination is the covalent link of target proteins with the small protein ubiquitin and serves as a signal to target protein degradation by the proteasome or to other outcomes such as endocytosis, degradation by the lysosome or specification of cellular localization. This paper reviews signal transduction pathways regulating EMT and being regulated by ubiquitination.

Mobile or fixed bearing for total knee arthroplasty? Ambulatory gait analysis results

Background: Mobile-bearing knee replacements have some theoretical advantages over fixed-bearing devices. However, very few randomized controlled clinical trials have been published to date, and studies showed little clinical and subjective advantages for the mobile-bearing using traditional systems of scoring. The choice of the ideal outcome measure to assess total joint replacement remains a complex issue. However, gait analysis provides objective and quantifying evidences of treatment evaluation. Significant methodological advances are currently made in gait analysis laboratories and ambulatory gait devices are now available. The goal of this study was to provide gait parameters as a new objective method to assess total knee arthroplasty outcome between patients with fixed- and mobile-bearing, using an ambulatory device with minimal sensor configuration. This randomized controlled double-blind study included to date 14 patients: the gait signatures of four patients with mobile-bearing were compared to the gait signatures of nine patients with fixed-bearing pre-operatively and post-operatively at 6 weeks, 3 months and 6 months. Each participant was asked to perform two walking trials of 30m long at his/her preferred speed and to complete a EQ-5D questionnaire, a WOMAC and Knee Society Score (KSS). Lower limbs rotations were measured by four miniature angular rate sensors mounted respectively, on each shank and thigh. A new method for a portable system for gait analysis has been developed with very encouraging results regarding the objective outcome of total knee arthroplasty using mobile- and fixed-bearings.

Ubiquitination and the Ubiquitin-Proteasome System as regulators of transcription and transcription factorsin epithelial mesenchymal transition of cancer.

Epithelial to Mesenchymal Transition (EMT) in cancer is a process that allows cancer cells to detach from neighboring cells, become mobile and metastasize and shares many signaling pathways with development. Several molecular mechanisms which regulate oncogenic properties in neoplastic cells such as proliferation, resistance to apoptosis and angiogenesis through transcription factors or other mediators are also regulators of EMT. These pathways and downstream transcription factors are, in their turn, regulated by ubiquitination and the Ubiquitin-Proteasome System (UPS). Ubiquitination, the covalent link of the small 76-amino acid protein ubiquitin to target proteins, serves as a signal for protein degradation by the proteasome or for other outcomes such as endocytosis, degradation by the lysosome or directing these proteins to specific cellular compartments. This review discusses aspects of the regulation of EMT by ubiquitination and the UPS and underlines its complexity focusing on transcription and transcription factors regulating EMT and are being regulated by ubiquitination.

High-precision satellite positioning system as a new tool to study the biomechanics of human locomotion.

New Global Positioning System (GPS) receivers allow now to measure a location on earth at high frequency (5Hz) with a centimetric precision using phase differential positioning method. We studied whether such technique was accurate enough to retrieve basic parameters of human locomotion. Eight subjects walked on an athletics track at four different imposed step frequencies (70-130steps/min) plus a run at free pace. Differential carrier phase localization between a fixed base station and the mobile antenna mounted on the walking person was calculated. In parallel, a triaxial accelerometer, attached to the low back, recorded body accelerations. The different parameters were averaged for 150 consecutive steps of each run for each subject (total of 6000 steps analyzed). We observed a perfect correlation between average step duration measured by accelerometer and by GPS (r=0.9998, N=40). Two important parameters for the calculation of the external work of walking were also analyzed, namely the vertical lift of the trunk and the velocity variation per step. For an average walking speed of 4.0km/h, average vertical lift and velocity variation were, respectively, 4.8cm and 0.60km/h. The average intra-individual step-to-step variability at a constant speed, which includes GPS errors and the biological gait style variation, were found to be 24. 5% (coefficient of variation) for vertical lift and 44.5% for velocity variation. It is concluded that GPS technique can provide useful biomechanical parameters for the analysis of an unlimited number of strides in an unconstrained free-living environment.

How can a dual oriT system contribute to efficient transfer of an integrative and conjugative element?

Integrative and conjugative elements (ICEs) are particularly interesting model systems for horizontal gene transfer, because they normally reside in an integrated state in the host chromosome but can excise and self-transfer under particular conditions, typically requiring exquisite regulatory cascades. Despite important advances in our understanding of the transfer mechanisms of a number of ICE, many essential details are lacking. Recently we reported that ICEclc, a 103 kb ICE of Pseudomonas knackmussii B13, has two active origins of transfer (oriTs), which is very much unlike conjugative plasmids that usually employ a single oriT. We discuss here how this dual oriT system could function and how it actually could have presented an evolutionary advantage for ICEclc distribution.

On the use of mobile inflatable hypoxic marquees for sport-specific altitude training in team sports.

BACKGROUND/AIM: With the evolving boundaries of sports science and greater understanding of the driving factors in the human performance physiology, one of the limiting factors has now become the technology. The growing scientific interest on the practical application of hypoxic training for intermittent activities such as team and racket sports legitimises the development of innovative technologies serving athletes in a sport-specific setting. METHODS: Description of a new mobile inflatable simulated hypoxic equipment. RESULTS: The system comprises two inflatable units-that is, a tunnel and a rectangular design, each with a 215 m(3) volume and a hypoxic trailer generating over 3000 Lpm of hypoxic air with FiO₂ between 0.21 and 0.10 (a simulated altitude up to 5100 m). The inflatable units offer a 45 m running lane (width=1.8 m and height=2.5 m) as well as a 8 m × 10 m dome tent. FiO₂ is stable within a range of 0.1% in normal conditions inside the tunnel. The air supplied is very dry-typically 10-15% relative humidity. CONCLUSIONS: This mobile inflatable simulated hypoxic equipment is a promising technological advance within sport sciences. It offers an opportunity for team-sport players to train under hypoxic conditions, both for repeating sprints (tunnel configuration) or small-side games (rectangular configuration).

The Learning Affect Monitor (LAM) - A computer-based system integrating quantitative and qualitative assessment of affective states in daily life.

The Learning Affect Monitor (LAM) is a new computer-based assessment system integrating basic dimensional evaluation and discrete description of affective states in daily life, based on an autonomous adapting system. Subjects evaluate their affective states according to a tridimensional space (valence and activation circumplex as well as global intensity) and then qualify it using up to 30 adjective descriptors chosen from a list. The system gradually adapts to the user, enabling the affect descriptors it presents to be increasingly relevant. An initial study with 51 subjects, using a 1 week time-sampling with 8 to 10 randomized signals per day, produced n = 2,813 records with good reliability measures (e.g., response rate of 88.8%, mean split-half reliability of .86), user acceptance, and usability. Multilevel analyses show circadian and hebdomadal patterns, and significant individual and situational variance components of the basic dimension evaluations. Validity analyses indicate sound assignment of qualitative affect descriptors in the bidimensional semantic space according to the circumplex model of basic affect dimensions. The LAM assessment module can be implemented on different platforms (palm, desk, mobile phone) and provides very rapid and meaningful data collection, preserving complex and interindividually comparable information in the domain of emotion and well-being.

Das GRADE-System: ein internationaler Ansatz zur Vereinheitlichung der Graduierung von Evidenz und Empfehlungen in Leitlinien. [The GRADE System: an international approach to standardize the graduation of evidence and recommendations in guidelines]

Clinical practice guidelines have become an important source of information to support clinicians in the management of individual patients. However, current guideline methods have limitations that include the lack of separating the quality of evidence from the strength of recommendations. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) working group, an international collaboration of guideline developers, methodologists, and clinicians have developed a system that addresses these shortcomings. Core elements include transparent methodology for grading the quality of evidence, the distinction between quality of the evidence and strength of a recommendation, an explicit balancing of benefits and harms of health care interventions, an explicit recognition of the values and preferences that underlie recommendations. The GRADE system has been piloted in various practice settings to ensure that it captures the complexity involved in evidence assessment and grading recommendations while maintaining simplicity and practicality. Many guideline organizations and medical societies have endorsed the system and adopted it for their guideline processes.

Frequent users of the emergency department in a universal health coverage system : a randomized controlled trial of a case-management intervention

BACKGROUND: Frequent emergency department users represent a small number of patients but account for a large number of emergency department visits. They should be a focus because they are often vulnerable patients with many risk factors affecting their quality of life (QoL). Case management interventions have resulted in a significant decrease in emergency department visits, but association with QoL has not been assessed. One aim of our study was to examine to what extent an interdisciplinary case management intervention, compared to standard emergency care, improved frequent emergency department users' QoL. METHODS: Data are part of a randomized, controlled trial designed to improve frequent emergency department users' QoL and use of health-care resources at the Lausanne University Hospital, Switzerland. In total, 250 frequent emergency department users (≥5 attendances during the previous 12 months; ≥ 18 years of age) were interviewed between May 2012 and July 2013. Following an assessment focused on social characteristics; social, mental, and somatic determinants of health; risk behaviors; health care use; and QoL, participants were randomly assigned to the control or the intervention group (n=125 in each group). The final sample included 194 participants (20 deaths, 36 dropouts, n=96 in the intervention group, n=99 in the control group). Participants in the intervention group received a case management intervention by an interdisciplinary, mobile team in addition to standard emergency care. The case management intervention involved four nurses and a physician who provided counseling and assistance concerning social determinants of health, substance-use disorders, and access to the health-care system. The participants' QoL was evaluated by a study nurse using the WHOQOL-BREF five times during the study (at baseline, and at 2, 5.5, 9, and 12 months). Four of the six WHOQOL dimensions of QoL were retained here: physical health, psychological health, social relationship, and environment, with scores ranging from 0 (low QoL) to 100 (high QoL). A linear, mixed-effects model with participants as a random effect was run to analyze the change in QoL over time. The effects of time, participants' group, and the interaction between time and group were tested. These effects were controlled for sociodemographic characteristics and health-related variables (i.e., age, gender, education, citizenship, marital status, type of financial resources, proficiency in French, somatic and mental health problems, and behaviors at risk).

Privacy as a Tradeoff: Introducing the Notion of Privacy Calculus for Context-Aware Mobile Applications

Evidences collected from smartphones users show a growing desire of personalization offered by services for mobile devices. However, the need to accurately identify users' contexts has important implications for user's privacy and it increases the amount of trust, which users are requested to have in the service providers. In this paper, we introduce a model that describes the role of personalization and control in users' assessment of cost and benefits associated to the disclosure of private information. We present an instantiation of such model, a context-aware application for smartphones based on the Android operating system, in which users' private information are protected. Focus group interviews were conducted to examine users' privacy concerns before and after having used our application. Obtained results confirm the utility of our artifact and provide support to our theoretical model, which extends previous literature on privacy calculus and user's acceptance of context-aware technology.