An Efficient Pairwise Key Establishment Scheme for Ad-hoc Mobile Clouds

An Ad-hoc Mobile Cloud (AMC) is a new computing model that allows sharing computing power of multiple mobile devices. For a diverse group of individuals that employ such computing model, in an ad-hoc manner, secure peer-to-peer communication becomes very important. Using private or pairwise keys to secure such communication is preferable to public-keys because of computation and energy requirements. With the advent of sensor enabled mobile devices, a protocol (SekGens) that uses sensor data to generate pairwise keys on demand has been proposed. To work successfully SekGens requires devices to be closely located and becomes infeasible for devices situated multiple hops away. SekGens is also expensive in computation and slow in key generation. In this thesis, we investigate how to enable devices in an AMC to establish pairwise keys. We propose an efficient solution which tries to reduce the number of executions of SekGens in the AMC, and establishes pairwise keys between mobile phones multiple hops away by distributing parts of the key on multiple routing paths. Our results show a reduction of up to 75% in the number of SekGens required to establish keys in an AMC, when compared to a naive approach. Also the execution time to come up with the optimal pairs is within 10s of seconds for reasonably large networks

Neurobehavioral assessment of seed extract of Swietenia mahagoni on zebrafish model

Traditional medicine in tropical areas often includes the use of Swietenia mahagoni to treat a wide range of conditions. However, preclinical testing is crucial to ensure their safety profile and address any remaining concerns about their efficacy.  The zebrafish model of open field test shows that decreased dopamine and cholinergic transmission causes impaired locomotion and diminished exploratory behavior. In addition to the elevation of 5-HT and GABA reported in the mirror bite test findings, the extract may have suppressed dopamine expression. The mirror-bite test and the light-dark test both showed elevated levels of GABA expression.  Findings from the predator avoidance test are very suggestive of a neurotransmitter-regulating action of the extract

Channel flow, tectonic overpressure, and exhumation of high-pressure rocks in the greater himalayas

The Himalayas are the archetype of continental collision, where a number of long-standing fundamental problems persist in the Greater Himalayan Sequence (GHS): (1) contemporaneous reverse and normal faulting, (2) inversion of metamorphic grade, (3) origin of high-(HP) and ultrahigh-pressure (UHP) rocks, (4) mode of ductile extrusion and exhumation of HP and UHP rocks close to the GHS hanging wall, (5) flow kinematics in the subduction channel, and (6) tectonic overpressure, here defined as TOP  Combining double low line Pĝ•PL where P is total (dynamic) pressure and PL is lithostatic pressure. In this study we couple Himalayan geodynamics to numerical simulations to show how one single model, upward-Tapering channel (UTC) flow, can be used to find a unified explanation for the evidence. The UTC simulates a flat-ramp geometry of the main underthrust faults, as proposed for many sections across the Himalayan continental subduction. Based on the current knowledge of the Himalayan subduction channel geometry and geological/geophysical data, the simulations predict that a UTC can be responsible for high TOP ( > 2). TOP increases exponentially with a decrease in UTC mouth width, and with an increase in underthrusting velocity and channel viscosity. The highest overpressure occurs at depths < ĝ'60 km, which, combined with the flow configuration in the UTC, forces HP and UHP rocks to exhume along the channel's hanging wall, as in the Himalayas. By matching the computed velocities and pressures wi

Neurobehavioral assessment of seed extract of Swietenia mahagoni on zebrafish model

Traditional medicine in tropical areas often includes the use of Swietenia mahagoni to treat a wide range of conditions. However, preclinical testing is crucial to ensure their safety profile and address any remaining concerns about their efficacy.  The zebrafish model of open field test shows that decreased dopamine and cholinergic transmission causes impaired locomotion and diminished exploratory behavior. In addition to the elevation of 5-HT and GABA reported in the mirror bite test findings, the extract may have suppressed dopamine expression. The mirror-bite test and the light-dark test both showed elevated levels of GABA expression.  Findings from the predator avoidance test are very suggestive of a neurotransmitter-regulating action of the extract

Tectono-metamorphic transitions in the higher Himalayan sequence: A clue for Main Central Thrust (MCT) localization in Darjeeling-Sikkim Himalaya

International audienceThis study recognizes a transition in the modes of ductile deformation across the Himalayan Crystalline Complex (HCC) from field and microstructural evidence. This transition leads to the Main Central Thrust (MCT) zone localization in the Darjeeling-Sikkim Himalaya. In the initial stage of crustal shortening (prior to ∼16 Ma), the HCC experienced temporally varying distributed ductile strains that produced regionally occurring planar fabrics and folds of three generations. Thereafter, the tectonic transition (from distributed to localized deformation) at ∼16 Ma occurred, forming the MCT zone in the HCC. This MCT zone (∼4-6 km thick) marks a diffuse metamorphic/rheological boundary between the hot HCC and the relatively colder Lesser Himalayan terrane to the south. The field data suggests that the base of compressed reverse paleo-isograds at the bottom of the MCT zone coincides with the transition of quartz creep mechanisms, from sub-grain rotation (SGR) to grain boundary migration (GBM). The present study documents the prograde metamorphic imprints to establish the P-T conditions of these multiple deformation episodes. Finally, this study presents a conceptual tectonic model, based on previous laboratory findings, to propose a two-stage tectono-thermal evolution of the Higher Himalaya