User-centred and context-aware identity management in mobile ad-hoc networks

The emergent notion of ubiquitous computing makes it possible for mobile devices to communicate and provide services via networks connected in an ad-hoc manner. These have resulted in the proliferation of wireless technologies such as Mobile Ad-hoc Networks (MANets), which offer attractive solutions for services that need flexible setup as well as dynamic and low cost wireless connectivity. However, the growing trend outlined above also raises serious concerns over Identity Management (IM) due to a dramatic increase in identity theft. The problem is even greater in service-oriented architectures, where partial identities are sprinkled across many services and users have no control over such identities. In this thesis, we review some issues of contextual computing, its implications and usage within pervasive environments. To tackle the above problems, it is essential to allow users to have control over their own identities in MANet environments. So far, the development of such identity control remains a significant challenge for the research community. The main focus of this thesis is on the area of identity management in MANets and emergency situations by using context-awareness and user-centricity together with its security issues and implications. Context- awareness allows us to make use of partial identities as a way of user identity protection and node identification. User-centricity is aimed at putting users in control of their partial identities, policies and rules for privacy protection. These principles help us to propose an innovative, easy-to-use identity management framework for MANets. The framework makes the flow of partial identities explicit; gives users control over such identities based on their respective situations and contexts, and creates a balance between convenience and privacy. The thesis presents our proposed framework, its development and lab results/evaluations, and outlines possible future work to improve the framework

Prior test experience produces changes of t-patterns spatial distribution in the elevated plus maze test

Aim of present research was to investigate in male Wistar rats whether a prior elevated plus maze experience modifies the temporal structure of the behavioral response following a retest applied after 24h. Video files were coded by means of a software coder and event log files generated for each subject were analyzed by means of a specific software for temporal pattern analysis (Theme). Present research shows a clear reduction of the number of t-patterns from trial one to trial two. This reduction is provoked by the disappearance of t-patterns consisting of behavioral elements occurring in the unprotected zones of the maze. The results suggest that the previous experience in the maze causes learning-dependent behavioral changes inducing a more clear-cut response to environmental anxiogenic conditions

T-type channel blockade impairs long-term potentiation at the parallel fiber-Purkinje cell synapse and cerebellar learning

CaV3.1 T-type channels are abundant at the cerebellar synapse between parallel fibers and Purkinje cells where they contribute to synaptic depolarization. So far, no specific physiological function has been attributed to these channels neither as charge carriers nor more specifically as Ca 2+ carriers. Here we analyze their incidence on synaptic plasticity, motor behavior, and cerebellar motor learning, comparing WT animals and mice where T-type channel function has been abolished either by gene deletion or by acute pharmacological blockade. At the cellular level, we show that Ca V3.1 channels are required for long-term potentiation at parallel fiber-Purkinje cell synapses. Moreover, basal simple spike discharge of the Purkinje cell in KO mice is modified. Acute or chronic T-type current blockade results in impaired motor performance in particular when a good body balance is required. Because motor behavior integrates reflexes and past memories of learned behavior, this suggests impaired learning. Indeed, subjecting the KO mice to a vestibulo-ocular reflex phase reversal test reveals impaired cerebellum-dependent motor learning. These data identify a role of low-voltage activated calcium channels in synaptic plasticity and establish a role for CaV3.1 channels in cerebellar learning

Anti-α-Internexin Autoantibody from Neuropsychiatric Lupus Induce Cognitive Damage via Inhibiting Axonal Elongation and Promote Neuron Apoptosis

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a major complication for lupus patients, which often leads to cognitive disturbances and memory loss and contributes to a significant patient morbidity and mortality. The presence of anti-neuronal autoantibodies (aAbs) has been identified; as examples, anti-NMDA receptors and anti-Ribsomal P aAbs have been linked to certain pathophysiological features of NPSLE.In the current study, we used a proteomic approach to identify an intermediate neurofilament alpha-internexin (INA) as a pathogenetically relevant autoantigen in NPSLE. The significance of this finding was then validated in an expanded of a cohort of NPSLE patients (n = 67) and controls (n = 270) by demonstrating that high titers of anti-INA aAb was found in both the serum and cerebrospinal fluid (CSF) of ∼50% NPSLE. Subsequently, a murine model was developed by INA immunization that resulted in pronounced cognitive dysfunction that mimicked features of NPSLE. Histopathology in affected animals displayed cortical and hippocampal neuron apoptosis. In vitro studies further demonstrated that anti-INA Ab mediated neuronal damage via inhibiting axonal elongation and eventually driving the cells to apoptosis.Taken together, this study identified a novel anti-neurofilament aAb in NPSLE, and established a hitherto undescribed mechanism of aAb-mediated neuron damage that could have relevance to the pathophysiology of NPSLE

Le 26RFa : un nouveau peptide pour la régulation glycémique

International audienc

Luxation tarso-métatarsienne : à propos d’un cas survenu chez un conducteur de deux roues

La luxation tarso-métatarsienne peut survenir chez les conducteurs d’engins à deux roues. Nous rapportons le cas d’un patient de sexe masculin âgé de 32 ans, qui a présenté une luxation columno-spatulaire homolatérale droit de l’interligne de Lisfranc, dans le but de montrer la particularité du mécanisme de survenue. C’est un mécanisme complexe avec un varus forcé de l’avant-pied.Mots clés : Luxation-Lisfranc-conducteur- deux roues- mécanism

Rapid Synthesis of Psychoplastogenic Tropane Alkaloids

Tropane alkaloids are an important class of biologically active small molecules characterized by their 8-azabicyclo[3.2.1]octane core. Because of their numerous medicinal applications, microbial biosynthesis and a variety of chemical syntheses have been designed for individual family members. However, current approaches are not amenable to late-stage structural diversification at N8, C3, C6, or C7, positions that are critical for modulating the biological properties of these molecules. Here, we describe a general approach to the synthesis of tropane alkaloids and their analogues that relies on the construction of the 8-azabicyclo[3.2.1]octane core through aziridination of a cycloheptadiene intermediate, followed by vinyl aziridine rearrangement. Using this strategy, we synthesized six tropane alkaloids and several analogues in only 5-7 steps. Given that the tropane alkaloid scopolamine has been reported to promote structural neuroplasticity and produce antidepressant effects, we tested five tropane-containing compounds for their ability to promote dendritic spine growth in cultured cortical neurons. We found that the orientation of the C3 substituent may play a role in the psychoplastogenic effects of tropane alkaloids. Our work provides a robust platform for producing tropane analogs for future structure-activity relationship studies

Temporal Patterns of Rodent Behavior in the Elevated Plus Maze Test

The aim of the present study was to evaluate, by means of a temporal pattern analysis, rat’s behavior in the elevated plus maze test. A specific software called THEME has been used. On the basis of an ethogram encompassing 24 behavioral elements, results demonstrated that 14 components represented the 98% of the displayed activities. 145 different temporal patterns have been detected; length distribution of such patterns showed that three-, four-, and five-elements patterns were more represented than two-elements ones. Finally, a complex temporal pattern encompassing 8 behavioral elements has been discussed. Present article demonstrated the presence of complex temporal patterns characterizing the behavior of rats in the elevated plus maze test

Temporal structure of the rat’s behavior in elevated plus maze test

Aim of the research was to evaluate, by means of quantitative and multivariate temporal pattern analyses, the behavior of Wistar rat in elevated plus maze (EPM) test. On the basis of an ethogram encompassing 24 behavioral elements, quantitative results showed that 130.14 ± 8.01 behavioral elements occurred in central platform and in closed arms (protected zones), whereas 88.62 ± 6.04 occurred in open arms (unprotected zones). Percent distribution was characterized by a prevalence of sniffing, walking and vertical exploration. Analysis of minute-by-minute duration evidenced a decrease for time spent in open arms and central platform and an increase for time spent in closed arms. As to multivariate t-pattern analysis, 126 different temporal patterns were detected. Behavioral stripes, summarizing distribution of such t-patterns along time, showed that several t-patterns were not homogeneously distributed along the test observational period: t-patterns encompassing behavioral events occurring prevalently in central platform-open arms were observed during the first minutes, whereas t-patterns structured on the basis of events occurring mainly in central platform-closed arms were detected during the last minutes. Therefore, during the observation in elevated plus maze, rat’s behavior undergoes significant rearrangements of its temporal features. Present research demonstrates, for the first time, the existence of complex and significantly timed behavioral sequences in the activity of Wistar rats tested in elevated plus maze. Application of t-pattern analysis can provide useful tools to characterize the behavioral dynamics of anxiety-related rodent behavior and differentiate the effect of various anxioselective substances