Methodology of the biological risk classification of animal pathogens in Belgium

The biological hazards posed by micro-organisms have lead to their categorisation into risk groups and the elaboration of classification lists. Current classification systems rely on criteria defined by the World Health Organization, which cover the severity of the disease the micro-organism might cause, its ability to spread and the availability of prophylaxis or efficient treatment. Animal pathogens are classified according to the definitions of the World Organization of Animal Health, which also consider economic aspects of disease. In Europe, classification is often directly linked to containment measures. The Belgian classification system however, only considers the inherent characteristics of the micro-organism, not its use, making the risk classification independent of containment measures. A common classification list for human and animal pathogens has been developed in Belgium using as comprehensive an approach as possible. Evolution of scientific knowledge will demand regular updating of classification lists. This paper describes the Belgian risk classification system and the methodology that was used for its peer-reviewed revision (with a focus on animal pathogens)

Numerical study of beam shape adaptation by anisotropic disk covering transducer or metamaterial

Metamaterials are intensely explored for their capabilities to modify sound beams. In addition to frequency filtering, acoustic lenses offer intriguing possibilities for shaping sound beams. For the time being, the versatility of metamaterials remains limitless. In beam-shape adaptation, however, their complexity suggests that manufacturers of transducers could benefit from combining metamaterials with more conventional materials. This paper investigates the transmission of a circumscribed beam through a stratum of anisotropic material to examine the change in beam shape after transmission. The incident sound is presumed to originate from a conventional transducer, possibly coated with a metamaterial to modify the sound field, before being transmitted through the anisotropic layer. Different incident beam shapes, such as conical-like, Gaussian, and pillar beams, are investigated. While the results are not exhaustive, they demonstrate the beam shape’s adaptability

Noise-aided gradient descent bit-flipping decoders approaching maximum likelihood decoding

International audienceIn the recent literature, the study of iterative LDPC decoders implemented on faulty-hardware has led to the counter-intuitive conclusion that noisy decoders could perform better than their noiseless version. This peculiar behavior has been observed in the finite codeword length regime, where the noise perturbating the decoder dynamics help to escape the attraction of fixed points such as trapping sets. In this paper, we will study two recently introduced LDPC decoders derived from noisy versions of the gradient descent bit-flipping decoder (GDBF). Although the GDBF is known to be a simple decoder with limited error correction capability compared to more powerful soft-decision decoders, it has been shown that the introduction of a random perturbation in the decoder could greatly improve the performance results, approaching and even surpassing belief propagation or min-sum based decoders. For both decoders, we evaluate the probability of escaping from a Trapping set, and relate this probability to the parameters of the injected noise distribution, using a Markovian model of the decoder transitions in the state space of errors localized on isolated trapping sets. In a second part of the paper, we present a modified scheduling of our algorithms for the binary symmetric channel, which allows to approach maximum likelihood decoding (MLD) at the cost of a very large number of iterations

Mii and MiiBump: Supporting pregnant women to continue or commence an active lifestyle

The purpose of this study was to investigate how women perceive exercising during pregnancy and whether existing technologies could be used to support active behaviours. Information for pregnant women who wish to continue or start exercising is limited and not readily offered. With the ever growing capability and accessibility to technologies research is warranted to investigate whether it could be used to help support exercising during pregnancy. An interpretative phenomenological approach was used to conduct in-depth interviews with five women, via purposive sampling. The data revealed that the participants perceived a number of barriers to active behaviours, such as the lack of a pregnant buddy with which to exercise. A lack of provided information was evident with the women claiming to have sought appropriate information themselves. Findings highlighted the potential for existing technologies to be utilised in order to support and enhance exercise behaviours during pregnancy