1,086 research outputs found

    Stellar Absorption Lines in the Spectra of Seyfert Galaxies

    Get PDF
    We have measured the strengths of Ca II Triplet and Mgb stellar absorption lines in the nuclear and off-nuclear spectra of Seyfert galaxies. These features are diluted to varying degrees by continuum emission from the active nucleus and from young stars. Ca II Triplet strengths can be enhanced if late-type supergiant stars dominate the near-IR light. Thus, objects with strong Ca II Triplet and weak Mgb lines may be objects with strong bursts of star formation. We find that for most of our sample the line strengths are at least consistent with dilution of a normal galaxy spectrum by a power law continuum, in accord with the standard model for AGN. However, for several Seyferts in our sample, it appears that dilution by a power law continuum cannot simultaneously explain strong Ca II Triplet and relatively weak Mgb. Also, these objects occupy the region of the IRAS color-color diagram characteristic of starburst galaxies. In these objects it appears that the optical to near-IR emission is dominated by late-type supergiants produced in a circumnuclear burst of star formation.Comment: 4 pages, 3 figures, to appear in Advances in Space Research, presented at "The AGN/Host Galaxy Connection" as part of the Scientific Assembly of COSPAR, July 12-18 Nagoya, Japa

    Cancer Biomarkers and Targets in Digestive Organs

    Get PDF
    Identification and development of cancer biomarkers and targets have greatly accelerated progress towards precision medicine in oncology. Studies of tumor biology have not only provided insights into the mechanisms underlying carcinogenesis, but also led to discovery of molecules that have been developed into cancer biomarkers and targets. Multi-platforms for molecular characterization of tumors using next-generation genomic sequencing, immunohistochemistry, in situ hybridization, and blood-based biopsies have greatly expanded the portfolio of potential biomarkers and targets. These cancer biomarkers have been developed for diagnosis, early detection, prognosis, and prediction of treatment response. The molecular targets have been exploited for anti-cancer therapy and delivery of therapeutic agents. This Special Issue of Biomedicines focuses on recent advances in the discovery, characterization, translation, and clinical application of cancer biomarkers and targets in malignant diseases of the digestive system. The goal is to stimulate basic and translational research and clinical collaboration in this exciting field with the hope of developing strategies for prevention and early detection/diagnosis of cancer in digestive organs, and improving therapeutic and psychosocial outcomes in patients with these malignant diseases

    A Study of Factors Influencing Green IT Practices, Buying and Subscription Behaviours of Computer and Mobile Devices, and Streaming Services

    Get PDF
    The pressure of environmental sustainability and the introduction of strict transnational and local environment laws, regulations and targets have catalysed the emergency of Green IT. On individual level, Green IT can be achieved through environmentally responsible behaviour to purchase, use and disposal of products and services without damaging the environment. This research aims to investigate the Green IT behaviour of young consumers including their day-to-day Green IT practices, buying behaviour of mobile and computer devices and subscription behaviour of streaming services. The findings show that: 1) Understanding of Green IT practices (specific knowledge) has a positive influence on PBC, 2) Consumer’s PBC has a positive influence on Green IT behaviour and 3) The communication strategy has a positive influence on PBC. Research results also show that young consumers’ buying and subscribing decision are strongly influenced by factors such as appearance, specification, features, content and price than Green IT factors. Available at: https://aisel.aisnet.org/pajais/vol11/iss1/4

    Transformation of stimulus correlations by the retina

    Get PDF
    Redundancies and correlations in the responses of sensory neurons seem to waste neural resources but can carry cues about structured stimuli and may help the brain to correct for response errors. To assess how the retina negotiates this tradeoff, we measured simultaneous responses from populations of ganglion cells presented with natural and artificial stimuli that varied greatly in correlation structure. We found that pairwise correlations in the retinal output remained similar across stimuli with widely different spatio-temporal correlations including white noise and natural movies. Meanwhile, purely spatial correlations tended to increase correlations in the retinal response. Responding to more correlated stimuli, ganglion cells had faster temporal kernels and tended to have stronger surrounds. These properties of individual cells, along with gain changes that opposed changes in effective contrast at the ganglion cell input, largely explained the similarity of pairwise correlations across stimuli where receptive field measurements were possible.Comment: author list corrected in metadat

    Structure-based stabilization of insulin as a therapeutic protein assembly via enhanced aromatic-aromatic interactions

    Get PDF
    Key contributions to protein structure and stability are provided by weakly polar interactions, which arise from asymmetric electronic distributions within amino acids and peptide bonds. Of particular interest are aromatic side chains whose directional π-systems commonly stabilize protein interiors and interfaces. Here, we consider aromatic-aromatic interactions within a model protein assembly: the dimer interface of insulin. Semi-classical simulations of aromatic-aromatic interactions at this interface suggested that substitution of residue TyrB26 by Trp would preserve native structure while enhancing dimerization (and hence hexamer stability). The crystal structure of a [TrpB26]insulin analog (determined as a T3Rf3 zinc hexamer at a resolution of 2.25 Å) was observed to be essentially identical to that of WT insulin. Remarkably and yet in general accordance with theoretical expectations, spectroscopic studies demonstrated a 150-fold increase in the in vitro lifetime of the variant hexamer, a critical pharmacokinetic parameter influencing design of long-acting formulations. Functional studies in diabetic rats indeed revealed prolonged action following subcutaneous injection. The potency of the TrpB26-modified analog was equal to or greater than an unmodified control. Thus, exploiting a general quantum-chemical feature of protein structure and stability, our results exemplify a mechanism-based approach to the optimization of a therapeutic protein assembly

    SUSY-Induced CP Violation in tt Decays at ee+e^-e^+ Colliders

    Full text link
    CP violation in the decays t+νbt \to \ell^+\nu b and tˉνˉbˉ\bar t \to \ell^-\bar\nu \bar b from the production process e^-e^+ \to \ttbar is discussed. Since the asymmetry proposed as a measure of CP violation vanishes even at the one-loop level in the Standard Model (SM), it may be a useful tool to search for sources of CP violation outside of the SM. As an illustration the asymmetry has been computed within supersymmetric extensions of the SM. Prospects for its measurement at future high-energy linear colliders are discussed.Comment: 17 pages, corrected former postscript output mistake

    Furthering the Growth of Cloud Computing by Providing Privacy as a Service

    Get PDF
    The evolution of Cloud Computing as a viable business solution for providing hardware and software has created many security concerns. Among these security concerns, privacy is often overlooked. If Cloud Computing is to continue its growth, this privacy concern will need to be addressed. In this work we discuss the current growth of Cloud Computing and the impact the public sector and privacy can have in furthering this growth. To begin to provide privacy protection for Cloud Computing, we introduce privacy constraints that outline privacy preferences. We propose the expansion of Cloud Service Level Agreements (SLAs) to include these privacy constraints as Quality of Service (QoS) levels. This privacy QoS must be agreed upon along with the rest of the QoS terms within the SLA by the Cloud consumer and provider. Finally, we introduce Privacy as a Service (PraaS) to monitor the agreement and provide enforcement if necessary

    Effect of medications with anti-cholinergic properties on cognitive function, delirium, physical function and mortality:a systematic review

    Get PDF
    Objectives: to determine the effect of drugs with anti-cholinergic properties on relevant health outcomes.Design: electronic published and unpublished literature/trial registries were systematically reviewed. Studies evaluating medications with anti-cholinergic activity on cognitive function, delirium, physical function or mortality were eligible.Results: forty-six studies including 60,944 participants were included. Seventy-seven percent of included studies evaluating cognitive function (n = 33) reported a significant decline in cognitive ability with increasing anti-cholinergic load (P 0.05). Five of the eight included studies reported a decline in physical function in users of anti-cholinergics (P < 0.05). Three of nine studies evaluating mortality reported that the use of drugs with anti-cholinergic properties was associated with a trend towards increased mortality, but this was not statistically significant. The methodological quality of the evidence-base ranged from poor to very good.Conclusion: medicines with anti-cholinergic properties have a significant adverse effect on cognitive and physical function, but limited evidence exists for delirium or mortality outcomes. © The Author 2014. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved
    corecore