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Our visual perception seems effortless, but the brain has a limited processing capacity which curtails the amount of sensory information that can be brought into conscious awareness at any moment in time. A widely studied exemplar of this limitation is the ‘attentional blink’ (AB), in which observers are unable to report the second of two rapidly sequential targets if it appears within 200-500 ms of the first. Despite the apparent ubiquity of the AB effect, its computational and neurophysiological underpinnings have remained elusive. Here we propose a simple computational model of temporal attention that unifies the AB with spatial and feature-based attention. We took a novel, integrative approach involving human psychophysics and functional brain imaging, along with neuronal recordings in mice to test this model. Specifically, we demonstrate that the AB only arises when visual targets have dissimilar representations in the brain but is absent when both targets have the same representation. Similarity in this context can be determined either by elementary features such as edge orientation, or by acquired, high-level factors such as numerical or alphabetical order. In this parsimonious model of the AB, attention to an initial target establishes a perceptual filter that is tuned to its unique representation in the brain. Subsequent items that match the filter remain available for conscious report, whereas those that do not match elude awareness altogether.

OBJECTIVE Did not wait (DNW) is a frequently cited ED key performance indicator. We conducted a network-based observational study of consecutive DNW presentations. METHODS Prospective cohort study of Western Sydney Local Health District with a primary outcome measure of reported 30-day all-cause mortality and secondary outcomes of demographic characteristics and representation risk. For re-presenting patients who were subsequently admitted, a manual review of electronic records and incident report systems based on a priori plan assessed each case for the length of stay and adverse outcomes. RESULTS During the study window, there were 1114 DNW presentations with 172 (15.4%) re-presentation within 72 h. The analysis of re-presented patients did not reveal adverse outcomes or prolonged length of stay. A review of available outcomes data revealed one DNW patient died within 30 days but had a previous palliative plan for terminal illness. CONCLUSION While a proportion of DNW patients re-presented within 72 h, an excess prevalence of poor outcomes were not observed.

A. aegypti has evolved to become an efficient vector for arboviruses such as Dengue but the mechanisms of host-pathogen immune tolerance are unknown. Toll receptors and Spaetzle (Spz) ligands have undergone duplication raising the possibility of neofunctionalization and mutualism to develop between arboviruses and mosquitoes. Here we present cryo-EM structures and biophysical characterisation of low affinity Toll5A-Spz1C complexes that display transient but specific interactions. Binding of the first ligand alters receptor-receptor interactions and promotes asymmetric contacts in the vicinity of the Z-loop in Toll5A. This conformation then restricts binding of a second ligand, while temporarily bridging the C-termini that promote signalling. Increased receptor concentrations promote inactivating head-to-head receptor assemblies. Furthermore, the transcriptional signature of Spz1C differs from other Spz cytokines in the control of genes involved in innate immunity, lipid metabolism and tissue regeneration. Given the remarkable DENV-induced expression patterns of these proteins, our data rationalises how Spz1C upregulation might promote antimicrobial defence in the midgut, and Toll5A upregulation, viral tolerance in the salivary glands.

The efficiency of sensory coding is affected both by past events (adaptation) and by expectation of future events (prediction). Here we employed a novel visual stimulus paradigm to determine whether expectation influences orientation selectivity in the primary visual cortex. We used two-photon calcium imaging (GCaMP6f) in awake mice viewing visual stimuli with different levels of predictability. The stimuli consisted of sequences of grating stimuli that randomly shifted in orientation or systematically rotated with occasionally unexpected rotations. At the single neuron and population level, there was significantly enhanced orientation-selective response to unexpected visual stimuli through a boost in gain, which was prominent in awake mice but also present to a lesser extent under anesthesia. We implemented a computational model to demonstrate how neuronal responses were best characterized when adaptation and expectation parameters were combined. Our results demonstrated that adaptation and prediction have unique signatures on activity of V1 neurons.

The rope coiling observed in liquid ink with high viscosity has been exploited in additive printing to fabricate architectures with periodically curled structures and tune their mechanical properties. However, the control over the coiling path relying on mechanical motion restricts the spatiotemporal resolution. We develop an electrically assisted high-resolution technique to manipulate coiling paths of viscous ink and structures of the deposited filament. By spatially programming the voltage applied onto the viscous ink, we show that the switching between different filament structures can be accomplished at single wavelength resolution, facilitating the rapid and accurate construction of sophisticated patterns. Furthermore, translational guiding of the electrocoiling enables rapid printing of filaments with complex structures at a line speed of 102 mm s−1. With a simplified trajectory of the printing head, large-area and multiscale patterns can be printed at an unprecedented speed; for instance, centimeter-sized architectures constructed from nanofibers with micron-sized curled structures can be completed in a few minutes. By enabling the printing of complex fiber networks with tunable shape and density, our work provides a route towards custom-design of fiber architectures with unique features such as spatially varying mechanical properties.

Pedestrian intention recognition is very important to develop robust and safe autonomous driving (AD) and advanced driver assistance systems (ADAS) functionalities for urban driving. In this work, we develop an end-to-end pedestrian intention framework that performs well on day- and night- time scenarios. Our framework relies on objection detection bounding boxes combined with skeletal features of human pose. We study early, late, and combined (early and late) fusion mechanisms to exploit the skeletal features and reduce false positives as well to improve the intention prediction performance. The early fusion mechanism results in AP of 0.89 and precision/recall of 0.79/0.89 for pedestrian intention classification. Furthermore, we propose three new metrics to properly evaluate the pedestrian intention systems. Under these new evaluation metrics for the intention prediction, the proposed end-to-end network offers accurate pedestrian intention up to half a second ahead of the actual risky maneuver., 5 pages, 6 figures, 5 tables, IEEE Asilomar SSC

Surgeons of today are faced with unprecedented challenges; necessitating a novel approach to pre-operative preparation which takes into account the specific tests each case poses. In this study, we examine patient-specific mental rehearsal for pre-surgical practice and assess whether this method has an additional effect when compared to generic mental rehearsal. Sixteen medical students were trained how to perform a simulated laparoscopic cholecystectomy (SLC). After baseline assessments, they were randomised to two equal groups and asked to complete three SLCs involving different anatomical variants. Prior to each procedure, Group A practiced mental rehearsal with the use of a pre-prepared checklist and Group B mental rehearsal with the checklist combined with virtual models matching the anatomical variations of the SLCs. The performance of the two groups was compared using simulator provided metrics and competency assessment tool (CAT) scoring by two blinded assessors. The participants performed equally well when presented with a “straight-forward” anatomy [Group A vs. Group B—time sec: 445.5 vs. 496 p = 0.64—NOM: 437 vs. 413 p = 0.88—PL cm: 1317 vs. 1059 p = 0.32—per: 0.5 vs. 0 p = 0.22—NCB: 0 vs. 0 p = 0.71—DVS: 0 vs. 0 p = 0.2]; however, Group B performed significantly better [Group A vs. B Total CAT score—Short Cystic Duct (SCD): 20.5 vs. 26.31 p = 0.02 η 2 = 0.32—Double cystic Artery (DA): 24.75 vs. 30.5 p = 0.03 η 2 = 0.28] and committed less errors (Damage to Vital Structures—DVS, SCD: 4 vs. 0 p = 0.03 η 2=0.34, DA: 0 vs. 1 p = 0.02 η 2 = 0.22). in the cases with more challenging anatomies. These results suggest that patient-specific preparation with the combination of anatomical models and mental rehearsal may increase operative quality of complex procedures.

The rising popularity of intelligent mobile devices and the daunting computational cost of deep learning-based models call for efficient and accurate on-device inference schemes. We propose a quantization scheme that allows inference to be carried out using integer-only arithmetic, which can be implemented more efficiently than floating point inference on commonly available integer-only hardware. We also co-design a training procedure to preserve end-to-end model accuracy post quantization. As a result, the proposed quantization scheme improves the tradeoff between accuracy and on-device latency. The improvements are significant even on MobileNets, a model family known for run-time efficiency, and are demonstrated in ImageNet classification and COCO detection on popular CPUs., Comment: 14 pages, 12 figures

Purpose: CD276 (B7-H3) is an immunoregulatory molecule that is reported to be widely expressed in pediatric embryonal tumors, pediatric sarcomas, and tumor infiltrating blood vessels. CD276 protein is expressed at low levels on several normal tissues, including cerebral cortex, liver and germinal lymph node. m276 is a fully-human IgG1 that binds with similar affinity to both mouse CD276 (24 nM kD) and human CD276 (29 nM kD) (Seaman et al., Cancer Cell, 2017). To generate an antibody-drug conjugate, m276 was site-specifically conjugated to the DNA damaging agent pyrrolobenzodiazepine (PBD) via a cleavable valine-alanine linker, providing m276-PBD with a Drug-to-Antibody Ratio (DAR) of 2. Here we examined the antitumor activity of m276-PBD against preclinical xenograft models of pediatric solid tumors. Experimental Procedures: Expression of CD276 across PPTC xenograft models (>200) representing leukemias, brain tumors and solid tumors was determined by RNA seq, and additionally in neuroblastoma models by IHC. Xenograft experiments were undertaken in heterotopic models using standard methods of the PPTC. Response criteria were tumor regression (PR, CR, maintained CR [at 6 weeks]) and Event-Free Survival (EFS). m276-PBD was administered by intraperitoneal injection at a dose of 0.5 mg/kg, once weekly x 3 consecutive weeks. Results: CD276 expression was high in most solid tumors (median 41 FPKM) with highest expression in osteosarcoma. Neuroblastoma, rhabdomyosarcoma, Wilms tumor and embryonal brain tumor models had similar levels of expression, whereas ALL models showed low expression. In vivo efficacy studies are ongoing, but data to date are available for 5 osteosarcoma, 4 rhabdomyosarcoma, 2 Ewing sarcoma and 2 Wilms tumors. Maintained Complete Response (MCR) at 6 weeks was attained in 2/5 osteosarcoma, 3/4 rhabdomyosarcoma and 1/2 Ewing sarcoma. CR was achieved in 1/2 Wilms tumor, 1/2 rhabdomyosarcoma, and 2/5 osteosarcoma models. Body weight loss ( Citation Format: Raushan Kurmasheva, E. Anders Kolb, Malcolm A. Smith, Beverly A. Teicher, Stephen W. Erickson, John M. Maris, Yael P. Mosse, Kateryna Krytska, David Groff, Matthew Tang, Yifei Wang, Brad St. Croix, Richard Gorlick, Peter J. Houghton. Initial testing of m276-PBD CD276 antibody-drug conjugate in preclinical models of pediatric cancers by the Pediatric Preclinical Testing Consortium (PPTC) [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C003. doi:10.1158/1535-7163.TARG-19-C003

Purpose The emulsification of silicone oil (SO) is associated with many complications. In this study, we investigate a new SO solvent, perfluorobutylpentane (F4H5) with 1% by volume of perfluorinated polyethers–polyethylene glycol–perfluorinated polyethers (PFPE-PEG-PFPE) triblock copolymer, for removing emulsified droplets. Methods An in vitro 3D printed model eye chamber was used to evaluate the efficiency of the three test liquids in removing SO droplets, namely saline, F4H5 and F4H5 with surfactant PFPE-PEG-PFPE. The numbers of SO droplets were quantified using a Coulter Counter. The stability of double emulsion formed was tested with a fluidic device based on electro-coalescence. Two retinal cell lines were used to test the biocompatibility of the liquids. Results The mean number of droplets remaining in the eye chamber after rinsing with a solution of F4H5 with surfactant was 13 315 ± 4620/ml compared to saline (23 460 ± 7595/ml; p

Modern electrically steerable antennas have the ability to evolve their far-field radiation pattern on nanosecond timescales. The transient radiation that occurs during this evolution cannot be captured by conventional radiation pattern measurements, which take at least several minutes to complete. We present a temporal and spatial sampling method of measuring the rapid temporal evolution of an electronically steerable antenna's near- and far-field radiation pattern, which allows for time-domain measurement of the radiation pattern of an antenna at relevantly short timescales and over an arbitrarily large solid angle. An experimental validation of the method is reported, in which an azimuth-plane measurement of a phased-array antenna captures the transient far-field radiation pattern as the antenna switches its main-beam scanning angle with 7-nanosecond time resolution.