Appropriate counseling approach to disclose HIV status to HIV-infected children: Chiradzulu, Malawi

Mexico AIDS Conference 200

Detection of app collusion potential using logic programming

Mobile devices pose a particular security risk because they hold personal details (accounts, locations, contacts, photos) and have capabilities potentially exploitable for eavesdropping (cameras/microphone, wireless connections). The Android operating system is designed with a number of built-in security features such as application sandboxing and permission-based access control. Unfortunately, these restrictions can be bypassed, without the user noticing, by colluding apps whose combined permissions allow them to carry out attacks that neither app is able to execute by itself. While the possibility of app collusion was first warned in 2011, it has been unclear if collusion is used by malware in the wild due to a lack of suitable detection methods and tools. This paper describes how we found the first collusion in the wild. We also present a strategy for detecting collusions and its implementation in Prolog that allowed us to make this discovery. Our detection strategy is grounded in concise definitions of collusion and the concept of ASR (Access-Send-Receive) signatures. The methodology is supported by statistical evidence. Our approach scales and is applicable to inclusion into professional malware detection systems: we applied it to a set of more than 50,000 apps collected in the wild. Code samples of our tool as well as of the detected malware are available

Estimation of the mechanical properties of the eye through the study of its vibrational modes

Measuring the eye's mechanical properties in vivo and with minimally invasive techniques can be the key for individualized solutions to a number of eye pathologies. The development of such techniques largely relies on a computational modelling of the eyeball and, it optimally requires the synergic interplay between experimentation and numerical simulation. In Astrophysics and Geophysics the remote measurement of structural properties of the systems of their realm is performed on the basis of (helio-)seismic techniques. As a biomechanical system, the eyeball possesses normal vibrational modes encompassing rich information about its structure and mechanical properties. However, the integral analysis of the eyeball vibrational modes has not been performed yet. Here we develop a new finite difference method to compute both the spheroidal and, specially, the toroidal eigenfrequencies of the human eye. Using this numerical model, we show that the vibrational eigenfrequencies of the human eye fall in the interval 100 Hz - 10 MHz. We find that compressible vibrational modes may release a trace on high frequency changes of the intraocular pressure, while incompressible normal modes could be registered analyzing the scattering pattern that the motions of the vitreous humour leave on the retina. Existing contact lenses with embebed devices operating at high sampling frequency could be used to register the microfluctuations of the eyeball shape we obtain. We advance that an inverse problem to obtain the mechanical properties of a given eye (e.g., Young's modulus, Poisson ratio) measuring its normal frequencies is doable. These measurements can be done using non-invasive techniques, opening very interesting perspectives to estimate the mechanical properties of eyes in vivo. Future research might relate various ocular pathologies with anomalies in measured vibrational frequencies of the eye.Comment: Published in PLoS ONE as Open Access Research Article. 17 pages, 5 color figure

A Survey of Wearable Biometric Recognition Systems

The growing popularity of wearable devices is leading to new ways to interact with the environment, with other smart devices, and with other people. Wearables equipped with an array of sensors are able to capture the owner’s physiological and behavioural traits, thus are well suited for biometric authentication to control other devices or access digital services. However, wearable biometrics have substantial differences from traditional biometrics for computer systems, such as fingerprints, eye features, or voice. In this article, we discuss these differences and analyse how researchers are approaching the wearable biometrics field. We review and provide a categorization of wearable sensors useful for capturing biometric signals. We analyse the computational cost of the different signal processing techniques, an important practical factor in constrained devices such as wearables. Finally, we review and classify the most recent proposals in the field of wearable biometrics in terms of the structure of the biometric system proposed, their experimental setup, and their results. We also present a critique of experimental issues such as evaluation and feasibility aspects, and offer some final thoughts on research directions that need attention in future work

The avian remains from El Juyo, Lower Magdalenian Cantabrian Spain

El Juyo is one of the Cantabrian sites of Iberia known from long ago for its important Lower Magdalenian sequence. The present study reports the results of the zooarchaeological and taphonomic analysis of the avian remains recovered at the site, which complements the archaeological and palaeoecological data already avail-able. The remains recovered are limited, but they seem to indicate that humans were the main accumulating agent in the site, with sporadic presence of owls' activity. Additionally, humans could have used birds for other purposes than as a dietary resource, as suggested by cut marks observed on two wing bones.info:eu-repo/semantics/publishedVersio

Managing emergency situations in the smart city: The smart signal

In a city there are numerous items, many of them unnoticed but essential; this is the case of the signals. Signals are considered objects with reduced technological interest, but in this paper we prove that making them smart and integrating in the IoT (Internet of Things) could be a relevant contribution to the Smart City. This paper presents the concept of Smart Signal, as a device conscious of its context, with communication skills, able to offer the best message to the user, and as a ubiquitous element that contributes with information to the city. We present the design considerations and a real implementation and validation of the system in one of the most challenging environments that may exist in a city: a tunnel. The main advantages of the Smart Signal are the improvement of the actual functionality of the signal providing new interaction capabilities with users and a new sensory mechanism of the Smart City