Temporal dynamics of travelling theta wave activity in infants responding to visual looming

A fundamental property of most animals is the ability to see whether an object is approaching on a direct collision course and, if so, when it will collide. Using high-density electroencephalography in 5- to 11-month-old infants and a looming stimulus approaching under three different accelerations, we investigated how the young human nervous system extracts and processes information for impending collision. Here we show that infants' looming related brain activity is characterized by theta oscillations. Source analyses reveal clear localised activity in the visual cortex. Analysing the temporal dynamics of the source waveform, we provide evidence that the temporal structure of different looming stimuli is sustained during processing in the more mature infant brain, providing infants with increasingly veridical time-to-collision information about looming danger as they grow older and become mobile

Microscope and spectacle : on the complexities of using new visual technologies to communicate about wildlife conservation

Acknowledgments We thank our interviewees for granting us access to data and permission to use images; dot.rural Digital Economy Hub, the University of Aberdeen, and the James Hutton Institute for funding and support; Gina Maffey, Tony James, Katrina Myrvang Brown, and two anonymous reviewers for their comments on earlier versions of the manuscript; and JP Vargheese for technical assistance.Peer reviewedPublisher PD

New Technological Interventions in Conservation Conflicts : Countering Emotions and Contested Knowledge

RCUK Digital Economy programme Grant number EP/G066051/1 Open access via Springer Compact AgreementPeer reviewedPublisher PD

Detection of near-field, low permittivity layers with Ground Penetrating Radar: analytical estimation of the reflection coefficient

peer reviewedThe reflection coefficient of GPR waves encountering embedded thin layers is commonly estimated using a plane wave, far field approximation. But when the thin layer is situated in the near field of the antenna, the spherical nature of the waves and the possible propagation of a lateral wave into the layer may have a strong influence on the measured reflected amplitude. In this work, we studied through 2D FDTD simulations the behavior of a radar wave interacting with thin layers of different thicknesses. The snapshots and radargrams showed a large influence of the layer thickness on the wave propagation. For the very thin layers, the evanescent wave plays a major role and the plane wave approximation gives a good estimation of the reflection coefficient. For thicker layers, the specific inclination of each multiple reflection has to be taken into account, as well as the lateral wave propagation. On the basis of these observations, we determined which analytical method should be used for the analytical prediction of the reflection coefficient, as a function of the layer thickness

EEG Biometrics: On the Use of Occipital Cortex Based Features from Visual Evoked Potentials

The potential of using Electro-Encephalo-Gram (EEG) data as a biometric identifier is studied. This is the first study that assesses looming stimuli for the creation of biometrically useful Visual Evoked Potentials (VEP), i.e. EEG responses due to visual stimuli. A novel method for the detection of VEP responses with minimal expert interaction is introduced. The EEG data, segmented based on the VEP, are used to create a reliable feature vector. In contrast to previous studies, we provide a publicly available evaluation dataset based on infants which is therefore not biased due to unhealthy individuals. Only data from the occipital cortex are used (i.e. about 3 of the many possible electrode positions in the scalp), making the potential EEG biometric capture devices relatively simpler

Non-Destructive Methods for the Detection of Delaminations in Concrete Bridge Decks

To detect delaminations in concrete bridge decks, the non-destructive techniques (NDT) permit a frequent inspection of the slabs without damaging the structures. Within this study, twelve samples were realized, presenting diverse horizontal defects simulating delaminations. They were scanned with high frequency GPR with the common offset (CO) and common mid point (CMP) methods. The electromagnetic waves speed and defects depth were determined from the CMPs. A 3D visualization program was also created to display the CO measurements. The visibility of the inserted defects revealed to be dependent on their lateral extension, their thickness and especially their constitutive material

Changes in the genomic content of circulating Bordetella pertussis strains isolated from the Netherlands, Sweden, Japan and Australia: adaptive evolution or drift?

Abstract Background Bordetella pertussis is the causative agent of human whooping cough (pertussis) and is particularly severe in infants. Despite worldwide vaccinations, whooping cough remains a public health problem. A significant increase in the incidence of whooping cough has been observed in many countries since the 1990s. Several reasons for the re-emergence of this highly contagious disease have been suggested. A particularly intriguing possibility is based on evidence indicating that pathogen adaptation may play a role in this process. In an attempt to gain insight into the genomic make-up of B. pertussis over the last 60 years, we used an oligonucleotide DNA microarray to compare the genomic contents of a collection of 171 strains of B. pertussis isolates from different countries. Results The CGH microarray analysis estimated the core genome of B. pertussis, to consist of 3,281 CDSs that are conserved among all B. pertussis strains, and represent 84.8% of all CDSs found in the 171 B. pertussis strains. A total of 64 regions of difference consisting of one or more contiguous CDSs were identified among the variable genes. CGH data also revealed that the genome size of B. pertussis strains is decreasing progressively over the past 60 years. Phylogenetic analysis of microarray data generated a minimum spanning tree that depicted the phylogenetic structure of the strains. B. pertussis strains with the same gene content were found in several different countries. However, geographic specificity of the B. pertussis strains was not observed. The gene content was determined to highly correlate with the ptxP-type of the strains. Conclusions An overview of genomic contents of a large collection of isolates from different countries allowed us to derive a core genome and a phylogenetic structure of B. pertussis. Our results show that B. pertussis is a dynamic organism that continues to evolve.</p