Performance of HAGRID array in beta delayed neutron emission measurements

One of the most prevalent decay modes of unstable nuclei is β[beta] decay. For nuclei far from stability these decays can be followed by the emission of a neutron. The Versatile Array of Neutron Detectors at Low Energy (VANDLE) is a proven detection system for measuring the energies of delayed neutrons. VANDLE has been upgraded to include high-efficiency scintillators for gamma-ray detection. This increases the sensitivity for the γ[gamma]-rays that can follow the neutron emission. These scintillator components form an array of large volume NaI detectors and the Hybrid Array of Gamma-Ray Detectors (HAGRiD), which is an array of LaBr3[LaBr3] scintillators (BrilLanCe 380™). An experimental campaign at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory was completed in the Spring of 2016. Beams of several 238U[238U] fission fragments were delivered to VANDLE. Some of the advantages and drawbacks of the new γ[gamma]-ray systems, in particular HAGRiD, will be presented in this work through the results for the decays of two neutron rich Rubidium isotopes (94Rb [94Rb] and 97Rb [97Rb])

The role of anterior cingulate cortex in the affective evaluation of conflict

An influential theory of anterior cingulate cortex (ACC) function argues that this brain region plays a crucial role in the affective evaluation of performance monitoring and control demands. Specifically, control-demanding processes such as response conflict are thought to be registered as aversive signals by ACC, which in turn triggers processing adjustments to support avoidance learning. In support of conflict being treated as an aversive event, recent behavioral studies demonstrated that incongruent (i.e., conflict inducing), relative to congruent, stimuli can speed up subsequent negative, relative to positive, affective picture processing. Here, we used fMRI to investigate directly whether ACC activity in response to negative versus positive pictures is modulated by preceding control demands, consisting of conflict and task-switching conditions. The results show that negative, relative to positive, pictures elicited higher ACC activation after congruent, relative to incongruent, trials, suggesting that ACC's response to negative (positive) pictures was indeed affectively primed by incongruent (congruent) trials. Interestingly, this pattern of results was observed on task repetitions but disappeared on task alternations. This study supports the proposal that conflict induces negative affect and is the first to show that this affective signal is reflected in ACC activation

Affective modulation of cognitive control is determined by performance-contingency and mediated by ventromedial prefrontal and cingulate cortex

Cognitive control requires a fine balance between stability, the protection of an on-going task-set, and flexibility, the ability to update a task-set in line with changing contingencies. It is thought that emotional processing modulates this balance, but results have been equivocal regarding the direction of this modulation. Here, we tested the hypothesis that a crucial determinant of this modulation is whether affective stimuli represent performance-contingent or task-irrelevant signals. Combining functional magnetic resonance imaging with a conflict task-switching paradigm, we contrasted the effects of presenting negative- and positive-valence pictures on the stability/flexibility trade-off in humans, depending on whether picture presentation was contingent on behavioral performance. Both the behavioral and neural expressions of cognitive control were modulated by stimulus valence and performance contingency: in the performance-contingent condition, cognitive flexibility was enhanced following positive pictures, whereas in the nonperformance-contingent condition, positive stimuli promoted cognitive stability. The imaging data showed that, as anticipated, the stability/flexibility trade-off per se was reflected in differential recruitment of dorsolateral frontoparietal and striatal regions. In contrast, the affective modulation of stability/flexibility shifts was mirrored, unexpectedly, by neural responses in ventromedial prefrontal and posterior cingulate cortices, core nodes of the “default mode” network. Our results demonstrate that the affective modulation of cognitive control depends on the performance contingency of the affect-inducing stimuli, and they document medial default mode regions to mediate the flexibility-promoting effects of performance-contingent positive affect, thus extending recent work that recasts these regions as serving a key role in on-task control processes

MicroNAS: Memory and Latency Constrained Hardware-Aware Neural Architecture Search for Time Series Classification on Microcontrollers

This paper presents MicroNAS, a system designed to automatically search and generate neural network architectures capable of classifying time series data on resource-constrained microcontrollers (MCUs) and generating standard tf-lite ML models. MicroNAS takes into account user-defined constraints on execution latency and peak memory consumption on a target MCU. This approach ensures that the resulting neural network architectures are optimised for the specific constraints and requirements of the MCU on which they are implemented. To achieve this, MicroNAS uses a look-up table estimation approach for accurate execution latency calculations, with a minimum error of only 1.02ms. This accurate latency estimation on MCUs sets it apart from other hardware-aware neural architecture search (HW-NAS) methods that use less accurate estimation techniques. Finally, MicroNAS delivers performance close to that of state-of-the-art models running on desktop computers, achieving high classification accuracies on recognised datasets (93.93% on UCI-HAR and 96.33% on SkodaR) while running on a Cortex-M4 MCU

The presence and influence of glacier surging around the Geladandong ice caps, North East Tibetan Plateau

This study was supported by the Strategic Priority Research Program of Chinese Academy of Sciences (XDA20100300).Many glaciers and ice caps on the Tibetan Plateau have retreated and lost mass in recent years in response to temperature increases, providing clear evidence of the impact of climate change on the region. There is increasing evidence that many of the glaciers on the Tibetan Plateau have also shown periodically dynamic behaviour in the form of glacier surging and some even catastrophic collapse events. In this study, we examine the prevalence of glacier surging at the Geladandong ice caps, North East Tibetan Plateau, to better understand the role of surge events in the evolution of glacier mass loss budgets. Using glacier surface elevation change data over the period 1969–2018 and glacier surface velocity data from the ITS_LIVE dataset, we find that 19 outlet glaciers of the ice caps are of surge-type. Our multi-temporal measurements of glacier mass balance show that surge-type glacier mass budgets vary depending on the portion of the surge-cycle captured by geodetic data. At the regional level, pre- and post-surge glacier mass loss variability does not bias regional mass budget estimates, but enhanced, or suppressed, mass loss estimates are likely when small groups of glaciers are examined. Our results emphasise the importance of accurate surge-type glacier inventories and the need to maximise geodetic data coverage over glacierised regions known to contain surge-type glaciers.Publisher PDFPeer reviewe

OpenEarable:Open Hardware Earable Sensing Platform

Earables are ear-worn devices that offer functionalities beyond basic audio in- and output. In this paper we present the ongoing development of a new, open-source, Arduino-based earable platform called OpenEarable. It is based on standard components, is easy to manufacture and costs roughly $40 per device at batch size ten. We present the first version of the device which is equipped with a series of sensors and actuators: a 3-axis accelerometer and gyroscope, an ear canal pressure and temperature sensor, an inward facing ultrasonic microphone as well as a speaker, a push button, and a controllable LED. We demonstrate the versatility of the prototyping platform through three different example application scenarios. In sum, OpenEarable offers a general-purpose, open sensing platform for earable research and development.<br/

Implications of Contemporary Bluegrass Music Performance at and around a New York City Jam Session

Bluegrass as it is played in the United States today is not simply a resistant category of country music, but performs a particular and emergent view of past/present relations. More than a "micromusic" mediating between "supercultures" and "subcultures" (in Mark Slobin's terms 1993), in fact bluegrass's complex history resists simple top down or bottom up perspectives, articulating a distinct space of authenticity. Active `genre tending' in a jam setting poetically articulates emergent social relations, in a specific spatiotemporal frame, at New York City's The Baggot Inn jam scene, a site of bluegrass performance at which the genre is employed creatively as a way of socializing and articulating contemporary presence. Learning a genre on an individual level is an actively embodied linking of technique and feeling, and differing listening experiences may lead to differing ideas of what a musical text represents. Expressive skill, executed through embodied musical gestures derived from specific pieces of music, may embed personal biography with social history and experience. Successful coperformance of a genre (bluegrass, in this case) requires a dynamic performative flexibility. This flexibility in turn can permanently affect both player and context, though different players may have to work to agree or disagree. These live, face to face interactions which depend on local specifics, maintain the coherence of the wider musical genre that facilitates those very actions themselves

Measurement of Untruncated Nuclear Spin Interactions via Zero- to Ultra-Low-Field Nuclear Magnetic Resonance

Zero- to ultra-low-field nuclear magnetic resonance (ZULF NMR) provides a new regime for the measurement of nuclear spin-spin interactions free from effects of large magnetic fields, such as truncation of terms that do not commute with the Zeeman Hamiltonian. One such interaction, the magnetic dipole-dipole coupling, is a valuable source of spatial information in NMR, though many terms are unobservable in high-field NMR, and the coupling averages to zero under isotropic molecular tumbling. Under partial alignment, this information is retained in the form of so-called residual dipolar couplings. We report zero- to ultra-low-field NMR measurements of residual dipolar couplings in acetonitrile-2-$^{13}$C aligned in stretched polyvinyl acetate gels. This represents the first investigation of dipolar couplings as a perturbation on the indirect spin-spin $J$-coupling in the absence of an applied magnetic field. As a consequence of working at zero magnetic field, we observe terms of the dipole-dipole coupling Hamiltonian that are invisible in conventional high-field NMR. This technique expands the capabilities of zero- to ultra-low-field NMR and has potential applications in precision measurement of subtle physical interactions, chemical analysis, and characterization of local mesoscale structure in materials.Comment: 6 pages, 3 figure