Mapping fibre orientation in complex-shaped biological systems with micrometre resolution by scanning X-ray microdiffraction

A fully automated procedure to extract and to image local fibre orientation in biological tissues from scanning X-ray diffraction is presented. The preferred chitin fibre orientation in the flow sensing system of crickets is determined with high spatial resolution by applying synchrotron radiation based X-ray microbeam diffraction in conjunction with advanced sample sectioning using a UV micro-laser. The data analysis is based on an automated detection of azimuthal diffraction maxima after 2D convolution filtering (smoothing) of the 2D diffraction patterns. Under the assumption of crystallographic fibre symmetry around the morphological fibre axis, the evaluation method allows mapping the three-dimensional orientation of the fibre axes in space. The resulting two-dimensional maps of the local fibre orientations - together with the complex shape of the flow sensing system - may be useful for a better understanding of the mechanical optimization of such tissues.

Are definitions of adiposity appropriate for identification of cardiovascular disease risk in South Asian populations?

South Asian populations living in the UK have a high prevalence of the metabolic syndrome, cardiovascular disease (CVD) and type 2 diabetes which impacts greatly on the morbidity and mortality of this ethnic group. The identification of ‘at risk’ individuals is essential to initiate reventative treatment. However, this is considerably hindered by the lack of appropriate cut-off values for anthropometric measures. CVD risk is significantly higher at a lower body mass index (BMI) in many Asian groups compared with Caucasians and adiposity (particularly central deposition) is higher at similar BMI levels. The definition of adiposity in Asians needs to be firmly established and appropriate lower BMI and waist circumference cut-offs implemented in ethnic subpopulations to facilitate appropriate treatment strategies.

Involuntary inhibition of movement initiation alters oculomotor competition resolution

Identifying a stimulus as the target for a goal-directed movement involves inhibiting competing responses. Separable inhibitory interconnections bias local competition to ensure only one stimulus is selected and to alter movement initiation. Behavioural evidence of these inhibitory processes comes from the effects of distracters on oculomotor landing positions and saccade latencies. Here, we investigate the relationship between these two sources of inhibition. Targets were presented with or without close and remote distracters. In separate experiments the possible position and identity of the target and distracters were manipulated. In all cases saccade landing position was found to be less affected by the presence of the close distracter when remote distracters were also present. The involuntary increase in the latency of saccade initiation caused by the presence of the remote distracters alters the state of competitive processes involved in selecting the saccade target thus changing its landing position.

A novel spectral representation of electromyographic signals

Time/frequency and temporal analyses have been widely used in biomedical signal processing. These methods represent important characteristics of a signal in both time and frequency domain. In this way, essential features of the signal can be viewed and analysed in order to understand or model the physiological system. Historically, Fourier spectral analyses have provided a general method for examining the global energy/frequency distributions. However, an assumption inherent to these methods is the stationarity of the signal. As a result, Fourier methods are not generally an appropriate approach in the investigation of signals with transient components. This work presents the application of a new signal processing technique, empirical mode decomposition and the Hilbert spectrum, in the analysis of electromyographic signals. The results show that this method may provide not only an increase in the spectral resolution but also an insight into the underlying process of the muscle contraction.

User-intimate requirements hierarchy resolution framework (UI-REF)

Abstract. This paper presents the User-Intimate Requirements Hierarchy Resolution Framework (UI-REF) based on earlier work (Badii 1997-2008) to optimise the requirements engineering process particularly to support userintimate interactive systems co-design. The stages of the UI- EF framework for requirements resolution-and-prioritisation are described. UI-REF has been established to ensure that the most-deeply-valued needs of the majority of stakeholders are elicited and ranked, and the root rationale for requirements evolution is trace-able and contextualised so as to help resolve stakeholder conflicts. UI-REF supports the dynamically evolving requirements of the users in the context of digital economy as under-pinned by online service provisioning. Requirements prioritisation in UI-REF is fully resolved while a promotion path for lower priority requirements is delineated so as to ensure that as the requirements evolve so will their resolution and prioritisation.

Towards semantic resolution of security in ambient environments

Driven by new network and middleware technologies such as mobile broadband, near-field communication, and context awareness the so-called ambient lifestyle will foster innovative use cases in different domains. In the EU project Hydra high-level security, trust and privacy concerns such as loss of control, profiling and surveillance are considered at the outset. At the end of this project the. Hydra middleware development platform will have been designed so as to enable developers to realise secure ambient scenarios. This paper gives a short introduction to the Hydra project and its approach to ensure security by design. Based on the results of a focus group analysis of the user domain "building automation" typical threats are evaluated and their risks are assessed. Then, specific security requirements with respect to security, privacy, and trust are derived in order to incorporate them into the Hydra Security Meta-Model. How concepts such as context, semantic resolution of security, and virtualisation support the overall Hydra approach will be introduced and illustrated on the basis of it technical building automation scenario.