Beyond LIF neurons on neuromorphic hardware

Neuromorphic systems aim to provide accelerated low-power simulation of Spiking Neural Networks (SNNs), typically featuring simple and efficient neuron models such as the Leaky Integrate-and-Fire (LIF) model. Biologically plausible neuron models developed by neuroscientists are largely ignored in neuromorphic computing due to their increased computational costs. This work bridges this gap through implementation and evaluation of a single compartment Hodgkin-Huxley (HH) neuron and a multi-compartment neuron incorporating dendritic computation on the SpiNNaker, and SpiNNaker2 prototype neuromorphic systems. Numerical accuracy of the model implementations is benchmarked against reference models in the NEURON simulation environment, with excellent agreement achieved by both the fixed- and floating-point SpiNNaker implementations. The computational cost is evaluated in terms of timing measurements profiling neural state updates. While the additional model complexity understandably increases computation times relative to LIF models, it was found a wallclock time increase of only 8× was observed for the HH neuron (11× for the mutlicompartment model), demonstrating the potential of hardware accelerators in the next-generation neuromorphic system to optimize implementation of complex neuron models. The benefits of models directly corresponding to biophysiological data are demonstrated: HH neurons are able to express a range of output behaviors not captured by LIF neurons; and the dendritic compartment provides the first implementation of a spiking multi-compartment neuron model with XOR-solving capabilities on neuromorphic hardware. The work paves the way for inclusion of more biologically representative neuron models in neuromorphic systems, and showcases the benefits of hardware accelerators included in the next-generation SpiNNaker2 architecture

Community-based prescribing for impetigo in remote Australia: An opportunity for antimicrobial stewardship

Background: To support antibiotic prescribing for both hospital and community-based health professionals working in remote North Western Australia, a multidisciplinary Antimicrobial Stewardship (AMS) Committee was established in 2013. This Committee is usually focused on hospital-based prescribing. A troubling increase in sulfamethoxazole/ trimethoprim resistance in Staphylococcus aureus antibiograms from 9 to 18% over 1 year prompted a shift in gaze to community prescribing. What we did: Finding a paucity of relevant research, we first investigated contextual factors influencing local prescribing. We also designed a systematic survey of experts with experience relevant to our setting using a structured response survey (12 questions) to better understand specific AMS risks. Using these findings, recommendations were formulated for the AMS Committee. What we learned: Prescribing recommendations in a regional Skin Infections Protocol had previously been altered in December 2014. From 15 experts, we received 9 comprehensive responses (60%) about AMS risks in community prescribing. If feasible, pre-scribing audits also would have been valuable. Ten recommendations regarding specific antibiotic recommendations were submitted to the AMS Committee. Strengthening AMS in remote settings: As AMS Committees in Australia usually focus on hospital-based prescribing, novel methods such as external expert opinion could inform delib-erations about community-based prescribing. Our approach meant that this AMS Committee was able to intervene in the 2017 organizational review of the regional Skin Infections Protocol used by prescribers likely unaware of AMS risks. This experience demonstrates the value of incorporating AMS principles in community-based prescribing in context of a remote setting

From Photodriven Charge Accumulation to Fueling Enzyme Cascades in Molecular Factories

In a multi-disciplinary team effort we gather experts on light-to-chemical energy conversion, artificial metalloenzymes, and bio-inspired polymer vesicles in order to construct molecular factories which produce added-value chemicals in an overall process fueled by solar energy. We outline our long-term vision and discuss specific challenges associated with this endeavor

Comparison of Natural Feature Descriptors for Rigid-Object Tracking for Real-Time Augmented Reality

This paper presents a comparison of natural feature descrip- tors for rigid object tracking for augmented reality (AR) applica- tions. AR relies on object tracking in order to identify a physical object and to superimpose virtual object on an object. Natu- ral feature tracking (NFT) is one approach for computer vision- based object tracking. NFT utilizes interest points of a physcial object, represents them as descriptors, and matches the descrip- tors against reference descriptors in order to identify a phsical object to track. In this research, we investigate four different nat- ural feature descriptors (SIFT, SURF, FREAK, ORB) and their capability to track rigid objects. Rigid objects need robust de- scriptors since they need to describe the objects in a 3D space. AR applications are also real-time application, thus, fast feature matching is mandatory. FREAK and ORB are binary descriptors, which promise a higher performance in comparison to SIFT and SURF. We deployed a test in which we match feature descriptors to artificial rigid objects. The results indicate that the SIFT de- scriptor is the most promising solution in our addressed domain, AR-based assembly training

Thermal and Visual Imaging to Assist with Juvenile Idiopathic Arthritis Examination of the Knees

Juvenile idiopathic arthritis (JIA) causes inflammation of the joints, and it is frequently associated with their pain and stiffness. Its timely diagnosis is important to avoid its progressive damage to the bones and cartilage. Increases in the joint’s temperature and redness could be indicators of active JIA, hence their accurate quantification could assist with diagnosis. Thermal and visual images of the knees in 20 JIA participants (age: mean = 11.2 years, standard deviation = 2.3 years) were studied. The median temperature of knees with active inflammation was 3.198% higher than that of inactive knees. This difference, examined by a Wilcoxon signed-rank test, was statistically significant (p = 0.0078). In six out of the eight participants who had one active inflamed knee, thermal imaging identified the corresponding knee as warmer. In 16 out of 20 participants, the knee identified as warmer by thermal imaging was also identified as having a greater colour change by visual imaging as compared to their respective reference regions. The devised methods could accurately quantify the colour and temperature of the knees. It was concluded that thermal and visual imaging methods can be valuable in examining JIA. Further studies involving a larger number of participants and more detailed explorations would be needed prior to clinical application

The Karyotype of the Yellow Dung Fly, Scathophaga stercoraria, a Model Organism in Studies of Sexual Selection

Knowledge of karyotypical characteristics of a species is essential for understanding how sexually selected and sexually antagonistic traits evolve. The yellow dung fly Scathophaga stercoraria L. (Diptera: Scathophagidae) is an established model system for studies of sexual selection and sexual conflict, but karyotypical data are lacking to date. Here, the karyotype of S. stercoraria was characterized using conventional Giemsa-staining and C-banding techniques. The diploid chromosome set consists of 6 pairs of bi-armed meta- or submetacentric chromosomes. The sex chromosomes are the largest chromosomes and constitute 30% of the total length of the diploid set in females and about 25% in males. Males are the heterogametic sex, and the length of the Y chromosome is about three-quarters of that of the X chromosome. C-banding revealed that both sex chromosomes are largely heterochromatic. In contrast, in the five autosome pairs, heterochromatin is limited to narrow bands in the centromeric regions. This karyotypic information will help provide a more profound understanding of the inheritance of phenotypic variation in reproductive traits and the chromosomal locations of underlying genes

Are You on My Wavelength? Interpersonal Coordination in Dyadic Conversations

Conversation between two people involves subtle nonverbal coordination in addition to speech. However, the precise parameters and timing of this coordination remain unclear, which limits our ability to theorize about the neural and cognitive mechanisms of social coordination. In particular, it is unclear if conversation is dominated by synchronization (with no time lag), rapid and reactive mimicry (with lags under 1 s) or traditionally observed mimicry (with several seconds lag), each of which demands a different neural mechanism. Here we describe data from high-resolution motion capture of the head movements of pairs of participants (n = 31 dyads) engaged in structured conversations. In a pre-registered analysis pathway, we calculated the wavelet coherence of head motion within dyads as a measure of their nonverbal coordination and report two novel results. First, low-frequency coherence (0.2–1.1 Hz) is consistent with traditional observations of mimicry, and modeling shows this behavior is generated by a mechanism with a constant 600 ms lag between leader and follower. This is in line with rapid reactive (rather than predictive or memory-driven) models of mimicry behavior, and could be implemented in mirror neuron systems. Second, we find an unexpected pattern of lower-than-chance coherence between participants, or hypo-coherence, at high frequencies (2.6–6.5 Hz). Exploratory analyses show that this systematic decoupling is driven by fast nodding from the listening member of the dyad, and may be a newly identified social signal. These results provide a step towards the quantification of real-world human behavior in high resolution and provide new insights into the mechanisms of social coordination

Developing cognitive complexity and value pluralism within prevention curricula:: An empirical assessment of the Living Well with Difference course for secondary schools in England

Purpose: To promote gains in cognitive complexity (measured by integrative complexity, IC) associated with recognition of validity in others’ viewpoints/values, supporting peaceful conflict reduction. Design: Assessment of effectiveness of Living Well with Difference (LWWD) course designed to promote critical thinking about contested social issues. LWWD was delivered to 199 secondary school students in England, comprising eight hours of sessions in curriculum time. Findings: Results using Paragraph Completion Tests showed that IC increased in the intervention condition in comparison to the smaller control condition IC gains. Resilience scores did not show significant gain, although it correlated moderately with IC gain. Research Limitations: Unequal numbers of control: intervention groups, non-random school sample, and a moderate amount of missing data are potential limitations. Practical Implications: The discussion explores the possible contribution that LWWD can make to citizenship education and ‘deep’ critical thinking that engages with emo-tions and values, complementing prevention curricula in the light of EU recommendations

Combined cooling and bio-treatment of beet sugar factory condenser water effluent

Submitted to Office of Water Resources Research, U.S. Department of Interior.Bibliography: pages 76-78.OWRR project no. A-008-COLO under agreement no. 14-31-0001-3006

Tuning the thiolen: Al(III) and Fe(III) thiolen complexes for the isoselective ROP of rac-lactide

A series of five iron and aluminum complexes bearing {ONSO} imine thiobis(phenolate) ligands have been prepared and applied to the ring-opening polymerization (ROP) of rac-lactide. Fe(1)Cl produced polylactide with a very strong isotactic bias (Pm = 0.79–0.89) and well-defined melting temperatures (Tm = 154–181 °C). The polymers have been characterized by a combination of 1H{1H} NMR, 13C{1H} NMR, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, and powder X-ray diffraction. Fe(1)Cl has also been shown to activate CO2, at atmospheric pressure and concentrations, to form a carbonato-bridged dimer. Fe(2–5)Cl and Al(1–5)Me were also active for lactide ROP demonstrating good-molecular-weight control (Đ = 1.04–1.12) and moderate isotactic preference (Pm = 0.56–0.72), with polymerization outcome correlating with ligand substituents