Comments on the security of the SPAPA strong password

The hash function based Strong Password Authentication Protocol with User Anonymity (SPAPA) was designed to protect users against monitoring by utilising temporary identities instead of true identities. In this letter we show that it is vulnerable to several attacks, including two which allow an adversary to link the activities of a user

Software Holography: Interferometric Data Analysis for the Challenges of Next Generation Observatories

Next generation radio observatories such as the MWA, LWA, LOFAR, CARMA and SKA provide a number of challenges for interferometric data analysis. These challenges include heterogeneous arrays, direction-dependent instrumental gain, and refractive and scintillating atmospheric conditions. From the analysis perspective, this means that calibration solutions can not be described using a single complex gain per antenna. In this paper we use the optimal map-making formalism developed for CMB analyses to extend traditional interferometric radio analysis techniques--removing the assumption of a single complex gain per antenna and allowing more complete descriptions of the instrumental and atmospheric conditions. Due to the similarity with holographic mapping of radio antenna surfaces, we call this extended analysis approach software holography. The resulting analysis algorithms are computationally efficient, unbiased, and optimally sensitive. We show how software holography can be used to solve some of the challenges of next generation observations, and how more familiar analysis techniques can be derived as limiting cases.Comment: in revie

The miswired brain: making connections from neurodevelopment to psychopathology

Developmental neurobiologists have made great progress in elucidating the molecular mechanisms underlying nervous system development. There has been less focus, however, on the consequences when these processes go wrong. As the evidence increases that mutations in neurodevelopmental genes are associated with major psychiatric disorders, defining these consequences assumes paramount importance in elucidating pathogenic mechanisms

Analysis of the fabric of undisturbed and pluviated silty sand under load over time

Microstructure of two undisturbed silty sands with 4% fines and 35% fines is described and quantified. The materials were sampled by the gel push sampling method. Upon reloading to their in situ stresses, the material fabric was fixed by resin impregnation. A qualitative and quantitative comparison of the microstructure was made with laboratory prepared dry deposited specimens (15% fines) which were loaded over different periods of time. The microstructure is quantified statistically by measuring particle orientation and the distribution of spatial distance between particles. Both undisturbed and reconstituted specimens show a preferred horizontal particle orientation, with little detectable change over time in the reconstituted samples. Spatial microstructural change was assessed using new parameter called index of dispersion. A greater index of dispersion suggests a more interlocked structure (hence, more structurally stable sample). Analysis of the reconstituted samples show that index of dispersion tends to increase with ageing, with the denser sample displaying greater change over time than the looser sample. Values of index of dispersion of reconstituted samples (15% fines) tend to lie between those of the undisturbed sample with 35% silt fines and with 5% fines, showing that this measure is not independent of the particle size distribution

Comment: Horng's identification scheme based on Shamir's 'RSA for paranoids'

In [1], Horng proposed an identification scheme based on Shamir's modified RSA ([2]). We show that the scheme is vulnerable to active attacks which enable the attacker to obtain the factorisation of the public key

Development of a Coherent Doppler Lidar for Precision Maneuvering and Landing of Space Vehicles

A coherent Doppler lidar has been developed to address NASAs need for a high-performance, compact, and cost-effective velocity and altitude sensor onboard its landing vehicles. Future robotic and manned missions to planetary bodies require precise ground-relative velocity vector and altitude data to execute complex descent maneuvers and safe, soft landing at a pre-designated site. This lidar sensor, referred to as a Navigation Doppler Lidar, meets the required performance of landing missions while complying with vehicle size, mass, and power constraints. Operating from over five kilometers altitude, the lidar obtains velocity and range precision measurements with 2 cm/sec and 2 meters, respectively, dominated by the vehicle motion. After a series of flight tests onboard helicopters and rocket-powered free-flyer vehicles, the Navigation Doppler Lidar is now being ruggedized for future missions to various destinations in the solar system

A cross-sectional survey investigating the desensitisation of graphic health warning labels and their impact on smokers, non-smokers and patients with COPD in a London cohort.

OBJECTIVES: There is a lack of evidence regarding the effectiveness of graphic health warning labels (GHWL) in different individuals, including patients with chronic obstructive pulmonary disease (COPD). Investigating knowledge and attitudes may allow better implementation of future public health policies. We hypothesised that differences in the impact of GHWL exist between non-smokers, smokers and patients with COPD, with decreased efficacy in those groups who are longer and more frequently exposed to them. PARTICIPANTS AND SETTING: 163 participants (54% male, aged 21-80) including 60 non-smokers, 53 smokers and 50 patients with COPD (Gold stage II-IV), attending London respiratory outpatient clinics, participated in case-controlled surveys (50 items). OUTCOME MEASURES: Ten different GHWL were shown and demographics, smoking history, plans to quit, smoking-risk awareness, emotional response, processing and impact of GHWL on behaviour were recorded. Patients were further asked to prioritise the hypothetical treatment or prevention of five specific smoking-related diseases. RESULTS: Smokers, in particular those with COPD, were less susceptible to GHWL than non-smokers; 53.4% of all participants expressed fear when looking at GHWL, non-smokers (71.9%) more so than smokers (39.8%, p<0.001). COPD participants were less aware of the consequences than non-COPD participants (p<0.001), including an awareness of lung cancer (p=0.001). Lung cancer (95%), oral cancer (90.2%), heart disease (84.7%) and stroke (71.2%) were correctly associated with smoking, whereas blindness was least associated (23.9%). However, blindness was prioritised over oral cancer, stroke and in patients with COPD also over heart disease when participants were asked about hypothetical treatment or prevention. CONCLUSIONS: GHWL are most effective in non-smokers and a desensitisation effect was observed in smokers and patients with COPD. As a consequence, a tailored and concerted public health approach to use such messages is required and 'blindness' deserves to be mentioned in this context because of an unexpectedly high-deterring impact