3,029 research outputs found
Testing a goal-driven account of involuntary attentional capture by threat
Attention has long been characterised within prominent models as reflecting a competition between goal-driven and stimulus-driven processes. It remains unclear, however, how involuntary attentional capture by affective stimuli, such as threat-laden content, fits into such models. While such effects were traditionally held to reflect stimulus-driven processes, recent research has increasingly implicated a critical role of goal-driven processes. Here we test an alternative goal-driven account of involuntary attentional capture by threat, using an experimental manipulation of goal-driven attention. To this end we combined the classic ‘contingent capture’ and ‘emotion-induced blink’ (EIB) paradigms in an RSVP task with both positive or threatening target search goals. Across six experiments, positive and threat distractors were presented in peripheral, parafoveal, and central locations. Across all distractor locations, we found that involuntary attentional capture by irrelevant threatening distractors could be induced via the adoption of a search goal for a threatening category; adopting a goal for a positive category conversely led to capture only by positive stimuli. Our findings provide direct experimental evidence for a causal role of voluntary goals in involuntary capture by irrelevant threat stimuli, and hence demonstrate the plausibility of a top-down account of this phenomenon. We discuss the implications of these findings in relation to current cognitive models of attention and clinical disorders
Supercomputing with MPI meets the Common Workflow Language standards: an experience report
Use of standards-based workflows is still somewhat unusual by
high-performance computing users. In this paper we describe the experience of
using the Common Workflow Language (CWL) standards to describe the execution,
in parallel, of MPI-parallelised applications. In particular, we motivate and
describe the simple extension to the specification which was required, as well
as our implementation of this within the CWL reference runner. We discuss some
of the unexpected benefits, such as simple use of HPC-oriented performance
measurement tools, and CWL software requirements interfacing with HPC module
systems. We close with a request for comment from the community on how these
features could be adopted within versions of the CWL standards.Comment: Submitted to 15th Workshop on Workflows in Support of Large-Scale
Science (WORKS20
Not looking for any trouble? Purely affective attentional settings do not induce goal-driven attentional capture
It is well established that directing goal-driven attention to a particular stimulus property (e.g. red), or a conceptual category (e.g. toys) can induce powerful involuntary capture by goal-matching stimuli. Here we tested whether broad affective search goals (e.g. for anything threat-related) could similarly induce a generalised capture to an entire matching affective category. Across four experiments, participants were instructed to search for threat-related images in a Rapid Serial Visual Presentation (RSVP) stream, while ignoring threat-related distractors presented in task-irrelevant locations. Across these experiments we found no evidence of goal-driven attentional capture by threat distractors when participants adopted a general ‘threat detection’ goal encompassing multiple sub-categories of threat (Experiments 1a, 1b). This was true even when there was partial overlap between the threat distractors and the search goal (i.e. subset of the targets matched the distractor; Experiment 2). However, when participants adopted a more specific goal for a single sub-category of threat (e.g. fearful faces), robust goal-driven capture occurred by distractors matching this sub-category (Experiment 3). These findings suggest that while affective criteria can be used in the guidance of attention, attentional settings based on affective properties alone may not induce goal-driven attentional capture. We discuss implications for recent goal-driven accounts of affective attentional biases
The SKA Mid-frequency All-sky continuum survey: Discovering the unexpected and transforming radio-astronomy
SKA is an instrument, not an experiment (Phil Diamond, Stellenbosch, 17 Feb 2014) We show that, in addition to specific science goals, there is a strong case for conducting an all-sky (i.e. the visible 3p steradians) SKA continuum survey which does not fit neatly into conventional science cases. History shows that the greatest scientific impact of most major telescopes (e.g., HST, VLA) lies beyond the original goals used to justify the telescope. The design of the telescope therefore needs to maximise the ultimate scientific productivity, in addition to achieving the specific science goals. In this chapter, we show that an all-sky continuum survey is likely to achieve transformational science in two specific respects
Structure of the complete, membrane-assembled COPII coat reveals a complex interaction network
COPII mediates Endoplasmic Reticulum to Golgi trafficking of thousands of cargoes. Five essential proteins assemble into a two-layer architecture, with the inner layer thought to regulate coat assembly and cargo recruitment, and the outer coat forming cages assumed to scaffold membrane curvature. Here we visualise the complete, membrane-assembled COPII coat by cryo-electron tomography and subtomogram averaging, revealing the full network of interactions within and between coat layers. We demonstrate the physiological importance of these interactions using genetic and biochemical approaches. Mutagenesis reveals that the inner coat alone can provide membrane remodelling function, with organisational input from the outer coat. These functional roles for the inner and outer coats significantly move away from the current paradigm, which posits membrane curvature derives primarily from the outer coat. We suggest these interactions collectively contribute to coat organisation and membrane curvature, providing a structural framework to understand regulatory mechanisms of COPII trafficking and secretion
Structure of the complete, membrane-assembled COPII coat reveals a complex interaction network
COPII mediates Endoplasmic Reticulum to Golgi trafficking of thousands of cargoes. Five essential proteins assemble into a two-layer architecture, with the inner layer thought to regulate coat assembly and cargo recruitment, and the outer coat forming cages assumed to scaffold membrane curvature. Here we visualise the complete, membrane-assembled COPII coat by cryo-electron tomography and subtomogram averaging, revealing the full network of interactions within and between coat layers. We demonstrate the physiological importance of these interactions using genetic and biochemical approaches. Mutagenesis reveals that the inner coat alone can provide membrane remodelling function, with organisational input from the outer coat. These functional roles for the inner and outer coats significantly move away from the current paradigm, which posits membrane curvature derives primarily from the outer coat. We suggest these interactions collectively contribute to coat organisation and membrane curvature, providing a structural framework to understand regulatory mechanisms of COPII trafficking and secretion
Determinants of E2-ubiquitin conjugate recognition by RBR E3 ligases
Abstract RING-between-RING (RBR) ubiquitin ligases work with multiple E2 enzymes and function through an E3-ubiquitin thioester intermediate. The RBR module comprises three domains, RING1, IBR and RING2 that collaborate to transfer ubiquitin from the E2~Ub conjugate, recognised by RING1, onto a catalytic cysteine in RING2 and finally onto the substrate in a multi-step reaction. Recent studies have shown that RING1 domains bind E2~Ub conjugates in an open conformation to supress ubiquitin transfer onto lysine residues and promote formation of the E3 thioester intermediate. However, how the nature of the E2 influences the ubiquitin transfer process is currently unclear. We report here a detailed characterization of the RBR/E2-conjugate recognition step that indicates that this mechanism depends on the nature of the E2 enzyme and differs between UbcH5 and UbcH7. In the case of UbcH5~Ub an interaction with ubiquitin is necessary to stabilize the transfer complex while recognition of UbcH7~Ub is driven primarily by E2-RING1 contacts. Furthermore our analysis suggests that RBRs, in isolation and in complex with ubiquitin-loaded E2s, are dynamic species and that their intrinsic flexibility might be a key aspect of their catalytic mechanism
Taking Blockchain Seriously
In the present techno-political moment it is clear that ignoring or dismissing the hype surrounding blockchain is unwise, and certainly for regulatory authorities and governments who must keep a grip on the technology and those promoting it, in order to ensure democratic accountability and regulatory legitimacy within the blockchain ecosystem and beyond. Blockchain is telling (and showing) us something very important about the evolution of capital and neoliberal economic reason, and the likely impact in the near future on forms and patterns of work, social organization, and, crucially, on communities and individuals who lack influence over the technologies and data that increasingly shape and control their lives. In this short essay I introduce some of the problems in the regulation of blockchain and offer counter-narratives aimed at cutting through the hype fuelling the ascendency of this most contemporary of technologies
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