Head turns bias the brain's internal random generator

SummaryNumerical and spatial cognition rely on common functional circuits in the parietal lobes of the brain [1]. While previous work has established that the mere perception of numbers can bias a subject's attention in space [2], the method of random digit generation has only recently been introduced to a rapidly growing literature exploring asymmetries in number space [3]. Here we show that human subjects' attempts to generate numbers ‘at random’ are systematically influenced by lateral head turns, which are known to reallocate spatial attention in the outside world. Specifically, while facing left, subjects produced relatively small numbers, whereas while facing right they tended to produce larger numbers. These results support current concepts of parietal cortex as mediating the interplay between spatial attention and abstract thought [4]

Stochastic IMT (insulator-metal-transition) neurons: An interplay of thermal and threshold noise at bifurcation

Artificial neural networks can harness stochasticity in multiple ways to enable a vast class of computationally powerful models. Electronic implementation of such stochastic networks is currently limited to addition of algorithmic noise to digital machines which is inherently inefficient; albeit recent efforts to harness physical noise in devices for stochasticity have shown promise. To succeed in fabricating electronic neuromorphic networks we need experimental evidence of devices with measurable and controllable stochasticity which is complemented with the development of reliable statistical models of such observed stochasticity. Current research literature has sparse evidence of the former and a complete lack of the latter. This motivates the current article where we demonstrate a stochastic neuron using an insulator-metal-transition (IMT) device, based on electrically induced phase-transition, in series with a tunable resistance. We show that an IMT neuron has dynamics similar to a piecewise linear FitzHugh-Nagumo (FHN) neuron and incorporates all characteristics of a spiking neuron in the device phenomena. We experimentally demonstrate spontaneous stochastic spiking along with electrically controllable firing probabilities using Vanadium Dioxide (VO$_2$) based IMT neurons which show a sigmoid-like transfer function. The stochastic spiking is explained by two noise sources - thermal noise and threshold fluctuations, which act as precursors of bifurcation. As such, the IMT neuron is modeled as an Ornstein-Uhlenbeck (OU) process with a fluctuating boundary resulting in transfer curves that closely match experiments. As one of the first comprehensive studies of a stochastic neuron hardware and its statistical properties, this article would enable efficient implementation of a large class of neuro-mimetic networks and algorithms.Comment: Added sectioning, Figure 6, Table 1, and Section II.E Updated abstract, discussion and corrected typo

Avalanche survival depends on the time of day of the accident: A retrospective observational study.

INTRODUCTION We aimed to investigate the relationship between the time of the day and the probability of survival of completely buried avalanche victims. We explored the frequency of avalanche burials occurring after sunset, and described victims' characteristics, duration of burial and rescue circumstances compared to daytime avalanches. METHODS In this retrospective, observational study, we analysed avalanche data from the registry of the Swiss Institute for Snow and Avalanche Research, from 1998 to 2020. RESULTS A total of 3,892 avalanche victims were included in the analysis, with 72 of the accidents (1.85%) occurring in the nighttime. Nearly 50% of the victims involved in nighttime avalanche accidents were completely buried, compared to about 25% of victims in daytime avalanches. Completely buried victims were rescued by a companion less often at night than in the daytime (15% vs. 51%, p<.001). The search and rescue of completely buried avalanche victims took longer during the nighttime compared to the daytime (median 89 min vs 20 min, p=.002). The probability of survival decreased as the day progressed; it was highest at around midday (63.0%), but decreased at sunset (40.4%) and was the lowest at midnight (28.7%). CONCLUSIONS Avalanche accidents at night are a rare event, and probability of survival after complete burial is lower during the nighttime compared to the daytime. The most relevant reason for this is the longer duration of burial, which is explained in part by the lower rate of companion rescue and the lower rate of victim localisation with an avalanche transceiver

Automated Counting of Bacterial Colony Forming Units on Agar Plates

Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates

Virus Movements on the Plasma Membrane Support Infection and Transmission between Cells

How viruses are transmitted across the mucosal epithelia of the respiratory, digestive, or excretory tracts, and how they spread from cell to cell and cause systemic infections, is incompletely understood. Recent advances from single virus tracking experiments have revealed conserved patterns of virus movements on the plasma membrane, including diffusive motions, drifting motions depending on retrograde flow of actin filaments or actin tail formation by polymerization, and confinement to submicrometer areas. Here, we discuss how viruses take advantage of cellular mechanisms that normally drive the movements of proteins and lipids on the cell surface. A concept emerges where short periods of fast diffusive motions allow viruses to rapidly move over several micrometers. Coupling to actin flow supports directional transport of virus particles during entry and cell-cell transmission, and local confinement coincides with either nonproductive stalling or infectious endocytic uptake. These conserved features of virus–host interactions upstream of infectious entry offer new perspectives for anti-viral interference

Public Sector Perspectives 2024: Empfehlungen für den öffentlichen Sektor

Nachhaltigkeit und Digitalisierung sind die zwei Megatrends des 21. Jahrhunderts. Das Institut Public Sector Transformation widmet sich diesen beiden Trends in zahlreichen Forschungsprojekten, die wir mit Praxispartnern aus Verwaltung, Wirtschaft und Zivilgesellschaft umsetzen. Der vorliegende Bericht fasst unsere Erfahrungen in komprimierter Form zusammen. Konkrete Erkenntnisse, zukünftige Entwicklungen und Empfehlungen zeigen Perspektiven auf, wohin die Reise im Jahr 2024 gehen wird und was es dabei zu beachten gilt. Diese gliedern sich in sechs zentralen Themencluster: Nachhaltigkeit & Gesellschaft, öffentliche Beschaffung, Smart Government, Daten, Public Sector IT und künstliche Intelligenz. Die «Public Sector Perspectives» sind eine Momentaufnahme, ein Innehalten in dieser herausfordernden Zeit. Wir zeigen, was uns beschäftigt, was wir wissen, was wir ahnen und wie wir uns die Zukunft des öffentlichen Sektors vorstellen. In 27 Kapiteln haben über 30 Forschende des Instituts Public Sector Transformation ihren aktuellen Wissensstand sowie ihre Handlungsempfehlungen aufgezeichnet

A multilingual audiometer simulator software for training purposes

A set of algorithms, which allows a computer to determine the answers of simulated patients during pure tone and speech audiometry, is presented. Based on these algorithms, a computer program for training in audiometry was written and found to be useful for teaching purposes

Graphical user interface (GUI) of the automated colony counter.

<p>GUI showing a typical result obtained after counting a blood agar plate with pneumococcal colonies. Red: counted as a single bacterial colony. Green: counted as double colonies.</p