292 research outputs found

    An iterative deep learning procedure for determining electron scattering cross-sections from transport coefficients

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    We propose improvements to the Artificial Neural Network (ANN) method of determining electron scattering cross-sections from swarm data proposed by coauthors. A limitation inherent to this problem, known as the inverse swarm problem, is the non-unique nature of its solutions, particularly when there exists multiple cross-sections that each describe similar scattering processes. Considering this, prior methods leveraged existing knowledge of a particular cross-section set to reduce the solution space of the problem. To reduce the need for prior knowledge, we propose the following modifications to the ANN method. First, we propose a Multi-Branch ANN (MBANN) that assigns an independent branch of hidden layers to each cross-section output. We show that in comparison with an equivalent conventional ANN, the MBANN architecture enables an efficient and physics informed feature map of each cross-section. Additionally, we show that the MBANN solution can be improved upon by successive networks that are each trained using perturbations of the previous regression. Crucially, the method requires much less input data and fewer restrictive assumptions, and only assumes knowledge of energy loss thresholds and the number of cross-sections present

    The role of carboxylato ligand dissociation in the oxidation of chrysin with H2O2 catalysed by [Mn-2 (III, IV)(mu-CH3COO)(mu-O)(2)(Me(4)dtne)](PF6)(2)

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    The aqueous and non-aqueous chemistry of the complex [Mn-2 (III,IV)(mu-CH3COO)(mu-O)(2)(Me(4)dtne)](PF6)(2) (where Me(4)dtne = 1,2-bis(4,7-dimethyl- 1,4,7-triazacyclonon-1-yl) ethane), which has been demonstrated as an exceptionally active catalyst in the bleaching of raw cotton and especially wood pulp at high pH (&gt;11), is explored by UV/vis absorption, Raman and EPR spectroscopies and cyclic voltammetry. The data indicate that dissociation of the mu-acetato bridge is essential to the catalyst activity and rationalises the effect of sequestrants such as DTPA on its performance.</p

    Radio Observations of the Hubble Deep Field South region: I. Survey Description and Initial Results

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    This paper is the first of a series describing the results of the Australia Telescope Hubble Deep Field South (ATHDFS) radio survey. The survey was conducted at four wavelengths - 20, 11, 6, and 3 cm, over a 4-year period, and achieves an rms sensitivity of about 10 microJy at each wavelength. We describe the observations and data reduction processes, and present data on radio sources close to the centre of the HDF-S. We discuss in detail the properties of a subset of these sources. The sources include both starburst galaxies and galaxies powered by an active galactic nucleus, and range in redshift from 0.1 to 2.2. Some of them are characterised by unusually high radio-to-optical luminosities, presumably caused by dust extinction.Comment: Accepted by AJ. 32 pages, 4 tables, 3 figures. PDF with full-resolution figures is on http://www.atnf.csiro.au/people/rnorris/N197.pd

    Nocturnal temperature controlled laminar airflow for treating atopic asthma: a randomised controlled trial

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       Objective To determine whether environmental control using nocturnal temperature controlled laminar airflow (TLA) treatment could improve the quality of life of patients with persistent atopic asthma. &lt;br&gt; &lt;br&gt;Design Randomised, double-blind, placebo-controlled, parallel-group trial. &lt;br&gt; &lt;br&gt;Setting Nineteen European asthma clinics. &lt;br&gt; &lt;br&gt;Participants 312 patients aged 7-70 with inadequately controlled persistent atopic asthma. &lt;br&gt; &lt;br&gt;Main outcome measure Proportion of patients with an increase of &amp;gt;= 0.5 points in asthma quality of life score after 1 year of treatment. &lt;br&gt; &lt;br&gt;Results TLA devices were successfully installed in the bedrooms of 282 (90%) patients included in the primary efficacy analysis. There was a difference in treatment response rate between active (143 of 189, 76%) and placebo (56 of 92, 61%) groups, difference 14.8% (95% CI 3.1 to 26.5, p=0.02).(3) In patients aged &amp;gt;= 12, on whom the study was powered, the difference in response rate was similar-active 106 of 143 (74%), placebo 42 of 70 (60%), difference 14.1% (0.6 to 27.7, p=0.059). There was a difference between groups in fractional exhaled nitric oxide change of -7.1 ppb (-13.6 to -0.7, p=0.03). Active treatment was associated with less increase in cat-specific IgE than placebo. There was no difference in adverse event rates between treatment groups. &lt;br&gt; &lt;br&gt;Conclusion Inhalant exposure reduction with TLA improves quality of life, airway inflammation and systemic allergy in patients with persistent atopic asthma. TLA may be a treatment option for patients with inadequately controlled persistent atopic asthma.funding agencies|Airsonett AB||National Institute for Health Research||National Institute for Health Research Biomedical Research Centre||MRC||Asthma UK Centre in Allergic Mechanisms of Asthma||</p

    Mitochondrial Hâ‚‚Oâ‚‚ emission and cellular redox state link excess fat intake to insulin resistance in both rodents and humans

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    High dietary fat intake leads to insulin resistance in skeletal muscle, and this represents a major risk factor for type 2 diabetes and cardiovascular disease. Mitochondrial dysfunction and oxidative stress have been implicated in the disease process, but the underlying mechanisms are still unknown. Here we show that in skeletal muscle of both rodents and humans, a diet high in fat increases the Hâ‚‚Oâ‚‚-emitting potential of mitochondria, shifts the cellular redox environment to a more oxidized state, and decreases the redox-buffering capacity in the absence of any change in mitochondrial respiratory function. Furthermore, we show that attenuating mitochondrial Hâ‚‚Oâ‚‚ emission, either by treating rats with a mitochondrial-targeted antioxidant or by genetically engineering the overexpression of catalase in mitochondria of muscle in mice, completely preserves insulin sensitivity despite a high-fat diet. These findings place the etiology of insulin resistance in the context of mitochondrial bioenergetics by demonstrating that mitochondrial Hâ‚‚Oâ‚‚ emission serves as both a gauge of energy balance and a regulator of cellular redox environment, linking intracellular metabolic balance to the control of insulin sensitivity. Original version available at http://www.jci.org/articles/view/3704

    OpenCrystalData : an open-access particle image database to facilitate learning, experimentation, and development of image analysis models for crystallization processes

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    Imaging and image-based process analytical technologies (PAT) have revolutionized the design, development, and operation of crystallization processes, providing greater process understanding through the characterization of particle size, shape and crystallization mechanisms in real-time. The performance of corresponding PAT models, including machine learning/artificial intelligence (ML/AI)-based approaches, is highly reliant on the data quality used for training or validation. However, acquiring high quality data is often time consuming and a major roadblock in developing image analysis models for crystallization processes. To address the lack of diverse, high-quality, and publicly available particle image datasets, this paper presents an initiative to create an open-access crystallization-related image database: OpenCrystalData (OCD, at www.kaggle.com/opencrystaldata/datasets). The datasets consist of images from different crystallization systems with different particle sizes and shapes captured under various conditions. The initial release consists of four different datasets, addressing the estimation of particle size distribution using in-situ images for different categories of particles and detection of anomalous particles for process monitoring purposes. Images are collected using various instruments, followed by case-specific processing steps, such as ground-truth labeling and particle size characterization using offline microscopy. Datasets are released on the online collaborative platform Kaggle, along with specific guidelines for each dataset. These datasets are aimed to serve as a resource for researchers to enable learning, experimentation, development, and evaluation and comparison of different analytical approaches and algorithms. Another goal of this initiative is to encourage researchers to contribute new datasets focusing on various systems and problem statements. Ultimately, OpenCrystalData is intended to facilitate and inspire new developments in imaging-based PAT for crystallization processes, encouraging a shift from time-consuming offline analysis towards comprehensive real-time process insights that drive product quality

    Transgenic Mice for a Tamoxifen-Induced, Conditional Expression of the Cre Recombinase in Osteoclasts

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    Background: Studies on osteoclasts, the bone resorbing cells, have remained limited due to the lack of transgenic mice allowing the conditional knockout of genes in osteoclasts at any time during development or adulthood. Methodology/Principal Finding: We report here on the generation of transgenic mice which specifically express a tamoxifen-inducible Cre recombinase in osteoclasts. These mice, generated on C57BL/6 and FVB background, express a fusion Cre recombinase-ERT2 protein whose expression is driven by the promoter of cathepsin K (CtsK), a gene highly expressed in osteoclasts. We tested the cellular specificity of Cre activity in CtsKCreERT2 strains by breeding with Rosa26LacZ reporter mice. PCR and histological analyses of the CtsKCreERT2LacZ positive adult mice and E17.5 embryos show that Cre activity is restricted largely to bone tissue. In vitro, primary osteoclasts derived from the bone marrow of CtsKCreERT2+/2LacZ+/2 adult mice show a Cre-dependent b-galactosidase activity after tamoxifen stimulation
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