Statistical Properties and Predictability of Extreme Epileptic Events

The use of extreme events theory for the analysis of spontaneous epileptic brain activity is a relevant multidisciplinary problem. It allows deeper understanding of pathological brain functioning and unraveling mechanisms underlying the epileptic seizure emergence along with its predictability. The latter is a desired goal in epileptology which might open the way for new therapies to control and prevent epileptic attacks. With this goal in mind, we applied the extreme event theory for studying statistical properties of electroencephalographic (EEG) recordings of WAG/Rij rats with genetic predisposition to absence epilepsy. Our approach allowed us to reveal extreme events inherent in this pathological spiking activity, highly pronounced in a particular frequency range. The return interval analysis showed that the epileptic seizures exhibit a highly-structural behavior during the active phase of the spiking activity. Obtained results evidenced a possibility for early (up to 7 s) prediction of epileptic seizures based on consideration of EEG statistical properties

Increasing Human Performance by Sharing Cognitive Load Using Brain-to-Brain Interface

Brain-computer interfaces (BCIs) attract a lot of attention because of their ability to improve the brain's efficiency in performing complex tasks using a computer. Furthermore, BCIs can increase human's performance not only due to human-machine interactions, but also thanks to an optimal distribution of cognitive load among all members of a group working on a common task, i.e., due to human-human interaction. The latter is of particular importance when sustained attention and alertness are required. In every day practice, this is a common occurrence, for example, among office workers, pilots of a military or a civil aircraft, power plant operators, etc. Their routinely work includes continuous monitoring of instrument readings and implies a heavy cognitive load due to processing large amounts of visual information. In this paper, we propose a brain-to-brain interface (BBI) which estimates brain states of every participant and distributes a cognitive load among all members of the group accomplishing together a common task. The BBI allows sharing the whole workload between all participants depending on their current cognitive performance estimated from their electrical brain activity. We show that the team efficiency can be increased due to redistribution of the work between participants so that the most difficult workload falls on the operator who exhibits maximum performance. Finally, we demonstrate that the human-to-human interaction is more efficient in the presence of a certain delay determined by brain rhythms. The obtained results are promising for the development of a new generation of communication systems based on neurophysiological brain activity of interacting people. Such BBIs will distribute a common task between all group members according to their individual physical conditions

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

Declarative, SAT-solver-based Scheduling for an Embedded Architecture with a Flexible Datapath

Abstract-Much like VLIW, statically scheduled architectures that expose all control signals to the compiler offer much potential for highly parallel, energy-efficient performance. Bau is a novel compilation infrastructure that leverages the LLVM compilation tools and the MiniSAT solver to generate efficient code for one such exposed architecture. We first build a compiler construction library that allows scheduling and resource constraints to be expressed declaratively in a domainspecific language, and then use this library to implement a compiler that generates programs that are 1.2-1.5 times more compact than either a baseline MIPS R2K compiler or a basic-block-based, sequentially phased scheduler

A SAT-Based Compiler for FlexCore

Much like VLIW, statically scheduled architectures that expose all control signals to the compiler offer much potential for highly parallel, energy-efficient performance. Bau is a novel compilation infrastructure that leverages the LLVM compilation tools and the MiniSAT solver to generate efficient code for one such exposed architecture. We first build a compiler construction library that allows scheduling and resource constraints to be expressed declaratively in a domain-specific language, and then use this library to implement a compiler that generates programs that are 1.2–1.5 times more compact than either a baseline MIPS R2K compiler or a basic-block-based, sequentially phased scheduler

Declarative, SAT-solver-based Scheduling for an Embedded Architecture with a Flexible Datapath

Much like VLIW, statically scheduled architectures that expose all control signals to the compiler offer much potential for highly parallel, energy-efficient performance. Bau is a novel compilation infrastructure that leverages the LLVM compilation tools and the MiniSAT solver to generate efficient code for one such exposed architecture. We first build a compiler construction library that allows scheduling and resource constraints to be expressed declaratively in a domain specific language, and then use this library to implement a compiler that generates programs that are 1.2–1.5 times more compact than either a baseline MIPS R2K compiler or a basic-block-based, sequentially phased scheduler

Synthesis and microbiological properties of novel bis-quaternary ammonium compounds based on 4,4′-oxydiphenol spacer

Novel gemini (tail–head–spacer–head–tail) bis-quaternary ammonium compounds with a 4,4′-oxydiphenol spacer between two pyridinium heads were synthesized and compared with commonly used antiseptics such as benzalkonium chloride and chlorhexidine gluconate. Analogues bearing CH, CH and CH aliphatic groups displayed potent broad spectrum in vitro activity against five bacterial strains and two fungi, with minimum inhibtory concentrations relatively independent of the counter ion