Artificial Intelligence Methods in Fault Tolerant Control

Non

Cervical cancer is not just a young woman's disease

Cervical screening programmes in many countries stop at around the age of 65 and much of the focus is often on younger women. For example, recent media campaigns in England and Wales have centred on lowering the age at first screening. Comparatively little attention has been given to older women despite the fact that they account for about a fifth of cases each year and half of deaths.1 2 Of the 3121 women diagnosed on average each year between 2009 and 2011 in the UK, only 64 were younger than 25 compared with 616 who were older than 65.1 As the population ages, this number of older women affected is set to increase. We argue that screening programmes should reflect this

Finite Element Simulations of Two-phase Flow and Floating Bodies Using FEniCS-HPC

We present a variational multiscale stabilized finite element method to solve the variable density incompressible Navier-Stokes equations for the simulation of two-phase flow. We introduce a level-set method based on the compression technique similar to [1]. For the simulation of floating devices we make use of a simplified rigid body motion scheme and a deforming mesh approach [2]. The mesh deforms elastically following the movement of the body. An implicit turbulence model is used where turbulence is modelled by the numerical stabilization. The described methods are implemented in the open source software framework FEniCS-HPC [3] provided with an automated methodology for discretization and error control. We are working in a project for marine energy generation together with Tecnalia R&I. In this context we simulate floating platforms that will be used for marine energy generation or device experimentation in the ocean. The aim is to study the dynamics of this kind of off-shore devices. Our simulation results are compared against the experimental data obtained by Tecnalia R&I company in the experimental tank of CEHIPAR in Spain. We also participate in the IEA-OES Task 10 project where different simulations of floating bodies are carried out. The results are compared against other groups simulations that use different methodologies

Direct finite element simulation of turbulent flow for marine based renewable energy

In this article we present a computational framework for simulation of turbulent flow in marine based renewable energy applications. In particular, we focus on floating structures and rotating turbines. This work is an extension to multiphase turbulent flow, of our existing framework of residual based turbulence modeling for single phase turbulent incompressible flow. We illustrate the framework in four examples: a regular wave test where we compare against an exact solution, the standard MARIN wave impact benchmark with experimental validation data, a vertical axis turbine with complex geometry from an existing turbine, and finally a prototype simulation of decay test in a coupled moving boundary rigid-body and two-phase fluid simulation.IEA-OES Task 1

Migration of Zebrafish Primordial Germ Cells: A Role for Myosin Contraction and Cytoplasmic Flow

SummaryThe molecular and cellular mechanisms governing cell motility and directed migration in response to the chemokine SDF-1 are largely unknown. Here, we demonstrate that zebrafish primordial germ cells whose migration is guided by SDF-1 generate bleb-like protrusions that are powered by cytoplasmic flow. Protrusions are formed at sites of higher levels of free calcium where activation of myosin contraction occurs. Separation of the acto-myosin cortex from the plasma membrane at these sites is followed by a flow of cytoplasm into the forming bleb. We propose that polarized activation of the receptor CXCR4 leads to a rise in free calcium that in turn activates myosin contraction in the part of the cell responding to higher levels of the ligand SDF-1. The biased formation of new protrusions in a particular region of the cell in response to SDF-1 defines the leading edge and the direction of cell migration

Impact of cervical screening on cervical cancer mortality: estimation using stage-specific results from a nested case-control study

Cancer Research UK (A16892 to P.S.)

Tunnel junctions based on interfacial 2D ferroelectrics

Van der Waals (vdW) heterostructures have opened new opportunities to develop atomically thin (opto)electronic devices with a wide range of functionalities. The recent focus on manipulating the interlayer twist angle has led to the observation of out-of-plane room temperature ferroelectricity in twisted rhombohedral (R) bilayers of transition metal dichalcogenides (TMDs). Here we explore the switching behaviour of sliding ferroelectricity using scanning probe microscopy domain mapping and tunnelling transport measurements. We observe well-pronounced ambipolar switching behaviour in ferroelectric tunnelling junctions (FTJ) with composite ferroelectric/non-polar insulator barriers and support our experimental results with complementary theoretical modelling. Furthermore, we show that the switching behaviour is strongly influenced by the underlying domain structure, allowing fabrication of diverse FTJ devices with various functionalities. We show that to observe the polarisation reversal, at least one partial dislocation must be present in the device area. This behaviour is drastically different from that of conventional ferroelectric materials and its understanding is an important milestone for future development of optoelectronic devices based on sliding ferroelectricity.Comment: 3 figure

A Solution for the Generalized Synchronization of a Class of Chaotic Systems Based on Output Feedback

A solution to the output-feedback generalized synchronization problem for two chaotic systems, namely, the master and the slave, is presented. The solution assumes that the slave is controlled by a single input, and the states of each system are partially known. To this end, both systems are expressed in their corresponding observable generalized canonical form, through their differential primitive element. The nonavailable state variables of both systems are recovered using a suitable Luenberger observer. The convergence analysis was carried out using the linear control approach in conjunction with the Lyapunov method. Convincing numerical simulations are presented to assess the effectiveness of the obtained solution

A Wireless Brain-Machine Interface for Real-Time Speech Synthesis

This is the published version, also available here: http://dx.doi.org/10.1371/journal.pone.0008218.Background Brain-machine interfaces (BMIs) involving electrodes implanted into the human cerebral cortex have recently been developed in an attempt to restore function to profoundly paralyzed individuals. Current BMIs for restoring communication can provide important capabilities via a typing process, but unfortunately they are only capable of slow communication rates. In the current study we use a novel approach to speech restoration in which we decode continuous auditory parameters for a real-time speech synthesizer from neuronal activity in motor cortex during attempted speech. Methodology/Principal Findings Neural signals recorded by a Neurotrophic Electrode implanted in a speech-related region of the left precentral gyrus of a human volunteer suffering from locked-in syndrome, characterized by near-total paralysis with spared cognition, were transmitted wirelessly across the scalp and used to drive a speech synthesizer. A Kalman filter-based decoder translated the neural signals generated during attempted speech into continuous parameters for controlling a synthesizer that provided immediate (within 50 ms) auditory feedback of the decoded sound. Accuracy of the volunteer's vowel productions with the synthesizer improved quickly with practice, with a 25% improvement in average hit rate (from 45% to 70%) and 46% decrease in average endpoint error from the first to the last block of a three-vowel task. Conclusions/Significance Our results support the feasibility of neural prostheses that may have the potential to provide near-conversational synthetic speech output for individuals with severely impaired speech motor control. They also provide an initial glimpse into the functional properties of neurons in speech motor cortical areas