Estimating numerical error in neural network simulations on Graphics Processing Units

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Dense gas and HII regions in the starburst galaxy NGC 253

The energetic activity in the nuclear barred region of NGC 253 is attributable to a burst of star formation. NGC 253 is in many ways a twin of the prototypical starburst galaxy M82; the strong non-thermal radio continuum, high far-infrared luminosity, and bright molecular emission of the central 1 Kpc parallel the morphology of the M82 starburst. Furthermore, the filamentary low ionization optical emission and extended x ray emission along the minor axis in NGC 253 is similar to a scaled down version of the well developed galactic bipolar wind in M82. The infrared luminosity of NGC 253, 3(exp 10) solar luminosity, is comparable to M82 but is emitted from a smaller region (Telesco and Harper 1980). This suggests that the NGC 253 starburst may be more intense and at an earlier evolutionary stage than M82. However, the presence of a non-stellar AGN in NGC 253 may complicate the comparison (Turner and Ho, 1985). Researchers used the Hat Creek millimeter interferometer to map emission from the J = 1 to 0 transitions of HCN and HCO(+) as well as 3 mm continuum emission, toward the nuclear region of NGC 253. The HCO(+) and continuum observations are sensitive to spatial scales from 6 to 45 seconds. The 2 minute field of view comfortably includes the entire starburst region (about 40 seconds; 650 pc). Because the longer baseline HCN observations are not yet complete, they are only sensitive to spatial scales from 15 to 45 seconds

Dynamic plantar loading index detects altered foot function in individuals with rheumatoid arthritis but not changes due to orthotic use

Background Altered foot function is common in individuals with rheumatoid arthritis. Plantar pressure distributions during gait are regularly assessed in this patient group; however, the association between frequently reported magnitude-based pressure variables and clinical outcomes has not been clearly established. Recently, a novel approach to the analysis of plantar pressure distributions throughout stance phase, the dynamic plantar loading index, has been proposed. This study aimed to assess the utility of this index for measuring foot function in individuals with rheumatoid arthritis.Methods Barefoot plantar pressures during gait were measured in 63 patients with rheumatoid arthritis and 51 matched controls. Additionally, 15 individuals with rheumatoid arthritis had in-shoe plantar pressures measured whilst walking in standardized footwear for two conditions: shoes-only; and shoes with prescribed custom foot orthoses. The dynamic plantar loading index was determined for all participants and conditions. Patient and control groups were compared for significant differences as were the shod and orthosis conditions.Findings The patient group was found to have a mean index of 0.19, significantly lower than the control group's index of 0.32 (p > 0.001, 95% CI [0.054, 0.197]). No significant differences were found between the shoe-only and shoe plus orthosis conditions. The loading index was found to correlate with clinical measures of structural deformity.Interpretation The dynamic plantar loading index may be a useful tool for researchers and clinicians looking to objectively assess dynamic foot function in patients with rheumatoid arthritis; however, it may be unresponsive to changes caused by orthotic interventions in this patient group.</p

A Model-Free Sampling Method for Estimating Basins of Attraction Using Hybrid Active Learning (HAL)

Understanding the basins of attraction (BoA) is often a paramount consideration for nonlinear systems. Most existing approaches to determining a high-resolution BoA require prior knowledge of the system's dynamical model (e.g., differential equation or point mapping for continuous systems, cell mapping for discrete systems, etc.), which allows derivation of approximate analytical solutions or parallel computing on a multi-core computer to find the BoA efficiently. However, these methods are typically impractical when the BoA must be determined experimentally or when the system's model is unknown. This paper introduces a model-free sampling method for BoA. The proposed method is based upon hybrid active learning (HAL) and is designed to find and label the "informative" samples, which efficiently determine the boundary of BoA. It consists of three primary parts: 1) additional sampling on trajectories (AST) to maximize the number of samples obtained from each simulation or experiment; 2) an active learning (AL) algorithm to exploit the local boundary of BoA; and 3) a density-based sampling (DBS) method to explore the global boundary of BoA. An example of estimating the BoA for a bistable nonlinear system is presented to show the high efficiency of our HAL sampling method.Comment: Update: 1) add the schematic of the magnet-induced bistable system, 2) emphasize that the proposed method can be implemented when the system's model is unknown. 6 pages, 5 figures, 2 table

Reframing How Physical Activity Reduces The Incidence of Clinically-Diagnosed Cancers: Appraising Exercise-Induced Immuno-Modulation As An Integral Mechanism

Undertaking a high volume of physical activity is associated with reduced risk of a broad range of clinically diagnosed cancers. These findings, which imply that physical activity induces physiological changes that avert or suppress neoplastic activity, are supported by preclinical intervention studies in rodents demonstrating that structured regular exercise commonly represses tumour growth. In Part 1 of this review, we summarise epidemiology and preclinical evidence linking physical activity or regular structured exercise with reduced cancer risk or tumour growth. Despite abundant evidence that physical activity commonly exerts anti-cancer effects, the mechanism(s)-of-action responsible for these beneficial outcomes is undefined and remains subject to ongoing speculation. In Part 2, we outline why altered immune regulation from physical activity - specifically to T cells - is likely an integral mechanism. We do this by first explaining how physical activity appears to modulate the cancer immunoediting process. In doing so, we highlight that augmented elimination of immunogenic cancer cells predominantly leads to the containment of cancers in a ‘precancerous’ or ‘covert’ equilibrium state, thus reducing the incidence of clinically diagnosed cancers among physically active individuals. In seeking to understand how physical activity might augment T cell function to avert cancer outgrowth, in Part 3 we appraise how physical activity affects the determinants of a successful T cell response against immunogenic cancer cells. Using the cancer immunogram as a basis for this evaluation, we assess the effects of physical activity on: (i) general T cell status in blood, (ii) T cell infiltration to tissues, (iii) presence of immune checkpoints associated with T cell exhaustion and anergy, (iv) presence of inflammatory inhibitors of T cells and (v) presence of metabolic inhibitors of T cells. The extent to which physical activity alters these determinants to reduce the risk of clinically diagnosed cancers – and whether physical activity changes these determinants in an interconnected or unrelated manner – is unresolved. Accordingly, we analyse how physical activity might alter each determinant, and we show how these changes may interconnect to explain how physical activity alters T cell regulation to prevent cancer outgrowth

Intensive exercise does not preferentially mobilise skin-homing T cells and NK cells

Purpose: This study investigated whether natural killer (NK) cells and CD8+ T cells expressing cutaneous lymphocyte antigen (CLA) – a homing molecule for endothelial cell leukocyte adhesion molecule 1 (ELAM-1), which enables transmigration to the skin – are selectively mobilised in response to acute exercise. Methods: Nine healthy males (mean ± SD age: 22.1 ± 3.4 years) completed two exercise sessions: high-intensity continuous cycling (‘continuous exercise’ at 80% MAX for 20 min) and low-volume high-intensity interval exercise (‘HIIE’ at 90% MAX 10 × 1 min repetitions with 1 min recovery intervals). Blood was collected before, immediately- and 30 min post-exercise for cryo-preservation of peripheral blood mononuclear cells. CLA+ and CLA− cells were quantified within NK subpopulations (CD56bright ‘regulatory’ and CD56dim ‘cytotoxic’ cells) as well as the following CD8+ T cell subpopulations: naive (‘NA’; CD45RA+CCR7+), central memory (‘CM’; CD45RA−CCR7+), effector-memory (‘EM’; CD45RA−CCR7−) and CD45RA-expressing effector-memory cells (‘EMRA’; CD45RA+CCR7−). Results: CLA+ NK cells and CD8+ memory T cells increased in response to both exercise bouts, but, overall, their numerical contribution to the exercise lymphocytosis was inferior to CLA− cells, which increased to a much greater extent during exercise. Tellingly, the most exercise-responsive cells – effector memory CD8+ cells and CD56dim cells – were CLA−. Conclusions: A small subset of CLA+ lymphocytes are mobilised into blood during acute intensive exercise, but CLA+ cells are not major contributors to exercise lymphocytosis, thus providing preliminary evidence that the skin is not a major origin, or homing-destination, of exercise-sensitive lymphocytes

Chemical vapor-deposited carbon nanofibers on carbon fabric for supercapacitor electrode applications

Entangled carbon nanofibers (CNFs) were synthesized on a flexible carbon fabric (CF) via water-assisted chemical vapor deposition at 800A degrees C at atmospheric pressure utilizing iron (Fe) nanoparticles as catalysts, ethylene (C2H4) as the precursor gas, and argon (Ar) and hydrogen (H-2) as the carrier gases. Scanning electron microscopy, transmission electron microscopy, and electron dispersive spectroscopy were employed to characterize the morphology and structure of the CNFs. It has been found that the catalyst (Fe) thickness affected the morphology of the CNFs on the CF, resulting in different capacitive behaviors of the CNF/CF electrodes. Two different Fe thicknesses (5 and 10 nm) were studied. The capacitance behaviors of the CNF/CF electrodes were evaluated by cyclic voltammetry measurements. The highest specific capacitance, approximately 140 F g(-1), has been obtained in the electrode grown with the 5-nm thickness of Fe. Samples with both Fe thicknesses showed good cycling performance over 2,000 cycles

Measuring the development of deep learning

The Higher Education Funding Council for England (HEFCE) in addressing teaching, learningand assessment (circular 26/95) list three key features, one of which is "[the] opportunity for andassessment of: development of ...values, motivation, or attitudes to learning."It has been reported (Fyfe, 1996) that the develop of attitudes to learning varies according towhether the programme of study is "Arts" or "Science" based. As students progress through Artsprogrammes they develop a deeper approach to learning whereas students following Scienceprogrammes develop a surface approach. In his report Fife makes no reference tointerdisciplinary programmes such as those related to the study of the environment which areinterdisciplinary.This study sets identify an appropriate method for recording students' approach to learning, toestablish base line data for four environmental orientated undergraduate programmes and toinvestigate the influence of a period of work-based learning on the development of attitudes tolearning