SAFIUS - A secure and accountable filesystem over untrusted storage

We describe SAFIUS, a secure accountable file system that resides over an untrusted storage. SAFIUS provides strong security guarantees like confidentiality, integrity, prevention from rollback attacks, and accountability. SAFIUS also enables read/write sharing of data and provides the standard UNIX-like interface for applications. To achieve accountability with good performance, it uses asynchronous signatures; to reduce the space required for storing these signatures, a novel signature pruning mechanism is used. SAFIUS has been implemented on a GNU/Linux based system modifying OpenGFS. Preliminary performance studies show that SAFIUS has a tolerable overhead for providing secure storage: while it has an overhead of about 50% of OpenGFS in data intensive workloads (due to the overhead of performing encryption/decryption in software), it is comparable (or better in some cases) to OpenGFS in metadata intensive workloads.Comment: 11pt, 12 pages, 16 figure

Political Economy of Tribal Development : A Case Study of Andhra Pradesh

The tribal population in the State of Andhra Pradesh, and in the country as a whole, is the most deprived and vulnerable community that faces severe economic exclusion. Although certain constitutional safeguards are provided, no significant economic, social and political mobility has taken place across this community. Contrary to Scheduled Castes and other Backward Castes who witnessed certain degrees of progress because of protective discrimination policies of the government, the Scheduled Tribes remain abysmally backward and socially excluded, still living in harsh environs. Our paper on "Political Economy of Tribal Development : A Case Study of Andhra Pradesh", delineates the situation of the Scheduled Tribes in the background of various policies of the state during the successive plan periods and its impact on their socio-economic mobility. Politically, this community is the most voiceless in the state. Their unsecured livelihood position in terms of lack of legal entitlements of the resources they use, both land and non-timber forest produce, push them into deep economic vulnerability. The paper also discusses the implications of the new act - Forest Right Act, 2006, on the livelihood security of the tribal communities and whether this act will finally lead to the inclusion of these people into the mainstream.Andhra Pradesh, India, economic exclusion, caste system, socio-economic mobility, Forest Right Act 2006

Particle diffusion in active fluids is non-monotonic in size

We experimentally investigate the effect of particle size on the motion of passive polystyrene spheres in suspensions of Escherichia coli. Using particles covering a range of sizes from 0.6 to 39 microns, we probe particle dynamics at both short and long time scales. In all cases, the particles exhibit super-diffusive ballistic behavior at short times before eventually transitioning to diffusive behavior. Surprisingly, we find a regime in which larger particles can diffuse faster than smaller particles: the particle long-time effective diffusivity exhibits a peak in particle size, which is a deviation from classical thermal diffusion. We also find that the active contribution to particle diffusion is controlled by a dimensionless parameter, the Peclet number. A minimal model qualitatively explains the existence of the effective diffusivity peak and its dependence on bacterial concentration. Our results have broad implications on characterizing active fluids using concepts drawn from classical thermodynamics.Comment: 5 Figure

Predication of Drug Target Interaction using Reliable Multicast Routing in Wireless Ad hoc Molecular Network

Wireless Ad hoc Molecular network consists of atoms in terms of nodes in the absence of administrative point. In this connection, there is a need to adopt molecular analogy to define the architecture. Prediction of Drug Target Interaction (DTI) is a major impact in molecular ad hoc network. Efforts were made to combine such information with data to define DTI and to construct biological space. The concept of Conditional Random Field (CRF) is used in our proposed reliable multicast routing to integrate genomic, chemical and functional data to predict DTI. Reliability of links was also maintained to increase the network performance. Based on the extensive simulation results, the proposed reliable routing protocol achieves better performance than existing schemes

Re: Controversies in Odontogenic Tumours Review

Letter to the Edito

Response of a Thin Flat Scored Metallic Disc Under Pressure Impulse

This paper presents the large deformation, and failure response of a thin flat scored metallic disc (FSMD) subjected to a pressure impulse as experienced in a break-away disc or an explosion vent. The response of this thin FSMD is numerically simulated for a loading rate and validated with an experiment, where a good agreement is found on plastic strains, burst pressure, and deformation pattern. The loading rate and several geometric parameters of FSMD significantly influence its response. Therefore, the influence of loading rate ( P& ), score depth and width-todisc thickness ratio (t 1 /t and b/t), diameter-to-disc thickness ratio (D/t), score length-to-disc radius ratio (l/R), score pattern, and score geometry on the deformation and failure response of the thin FSMD is thoroughly investigated. The studies demonstrate that 1) the failure initiation point shifts from disc centre to between 1/5th and 1/3rd radius for loading rates ≤ 25 MPa/s; 2) the responses such as burst pressure, burst time, central deflection, and equivalent strain are i) sensitive to the loading rates up to 100 MPa/s, ii) sensitive to score’s depth, only up to 0.6t and insensitive to score’s width, iii) significantly unaffected for the number of scores N > 8, iv) stabilised for l/R > 0.5 and D/t > 250, v) almost the same for semi-circular, rectangular and triangular score geometries, and vi) very minimal for the number of scores N = 3; and 3) the failure do not initiate and propagate along all scores for N > 4 in the disc