679 research outputs found

    Heating of the molecular gas in the massive outflow of the local ultraluminous-infrared and radio-loud galaxy 4C12.50

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    We present a comparison of the molecular gas properties in the outflow vs. in the ambient medium of the local prototype radio-loud and ultraluminous-infrared galaxy 4C12.50 (IRAS13451+1232), using new data from the IRAM Plateau de Bure interferometer and 30m telescope, and the Herschel space telescope. Previous H_2 (0-0) S(1) and S(2) observations with the Spitzer space telescope had indicated that the warm (~400K) molecular gas in 4C12.50 is made up of a 1.4(+-0.2)x10^8 M_sun ambient reservoir and a 5.2(+-1.7)x10^7 M_sun outflow. The new CO(1-0) data cube indicates that the corresponding cold (25K) H_2 gas mass is 1.0(+-0.1)x10^10 M_sun for the ambient medium and <1.3x10^8 M_sun for the outflow, when using a CO-intensity-to-H_2-mass conversion factor alpha of 0.8 M_sun /(K km/s pc^2). The combined mass outflow rate is high, 230-800 M_sun/yr, but the amount of gas that could escape the galaxy is low. A potential inflow of gas from a 3.3(+-0.3)x10^8 M_sun tidal tail could moderate any mass loss. The mass ratio of warm-to-cold molecular gas is >= 30 times higher in the outflow than in the ambient medium, indicating that a non-negligible fraction of the accelerated gas is heated to temperatures at which star formation is inefficient. This conclusion is robust against the use of different alpha factor values, and/or different warm gas tracers (H_2 vs. H_2 plus CO): with the CO-probed gas mass being at least 40 times lower at 400K than at 25K, the total warm-to-cold mass ratio is always lower in the ambient gas than in the entrained gas. Heating of the molecular gas could facilitate the detection of new outflows in distant galaxies by enhancing their emission in intermediate rotational number CO lines.Comment: A&A, in pres

    Arabidopsis Response Regulators ARR3 and ARR4 Play Cytokinin-Independent Roles in the Control of Circadian Period

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    Light and temperature are potent environmental signals used to synchronize the circadian oscillator with external time and photoperiod. Phytochrome and cryptochrome photoreceptors integrate light quantity and quality to modulate the pace and phase of the clock. PHYTOCHROME B (phyB) controls period length in red light as well as the phase of the clock in white light. phyB interacts with ARABIDOPSIS RESPONSE REGULATOR4 (ARR4) in a light-dependent manner. Accordingly, we tested ARR4 and other members of the type-A ARR family for roles in clock function and show that ARR4 and its closest relative, ARR3, act redundantly in the Arabidopsis thaliana circadian system. Loss of ARR3 and ARR4 lengthens the period of the clock even in the absence of light, demonstrating that they do so independently of active phyB. In addition, in white light, arr3,4 mutants show a leading phase similar to phyB mutants, suggesting that circadian light input is modulated by the interaction of phyB with ARR4. Although type-A ARRs are involved in cytokinin signaling, the circadian defects appear to be independent of cytokinin, as exogenous cytokinin affects the phase but not the period of the clock. Therefore, ARR3 and ARR4 are critical for proper circadian period and define an additional level of regulation of the circadian clock in Arabidopsis

    Identity-Based Blind Signature Scheme with Message Recovery

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    Blind signature allows a user to obtain a signature on a message without revealing anything about the message to the signer. Blind signatures play an important role in many real world applications such as e-voting, e-cash system where anonymity is of great concern. Due to the rapid growth in popularity of both wireless communications and mobile devices, the design of secure schemes with low-bandwidth capability is an important research issue. In this paper, we present a new blind signature scheme with message recovery in the ID-based setting using bilinear pairings over elliptic curves. The proposed scheme is unforgeable with the assumption that the Computational Diffie-Hellman problem is hard. We compare our scheme with the related schemes in terms of computational and communicational point of view

    Avoiding spurious feedback loops in the reconstruction of gene regulatory networks with dynamic bayesian networks

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    Feedback loops and recurrent structures are essential to the regulation and stable control of complex biological systems. The application of dynamic as opposed to static Bayesian networks is promising in that, in principle, these feedback loops can be learned. However, we show that the widely applied BGe score is susceptible to learning spurious feedback loops, which are a consequence of non-linear regulation and autocorrelation in the data. We propose a non-linear generalisation of the BGe model, based on a mixture model, and demonstrate that this approach successfully represses spurious feedback loops

    Guillain-Barre Syndrome: A Case Report

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    Guillain-Barre syndrome (GBS) is a complicated degenerative neurological disorder which can be acute or chronic in nature. It is an acquired condition which is characterized by progressive, symmetrical, proximal and distal tingling and weakness. Muscle stretch reflexes are decreased to absent and loss of sensation is common. Etiology remains unclear but pathophysiology includes demyelination of spinal nerve roots. Death is rare. Early diagnosis and prompt referral should occur in severe cases due to the incidence of potential ventilation &nbsp;&nbsp;failure and cardiovascular instability in some patients. The case of a 26-year-old male presenting to a physician is described. The importance of a correct diagnosis by the physician and the subsequent management is reviewed. Key words: Guillain-Barre syndrome, extremity weakness, peripheral nerves, traum

    Distinct and shared gene expression for human innate versus adaptive helper lymphoid cells

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    Innate lymphoid cells (ILCs) are the latest identified innate immune cell family. Given their similarity in transcription factor expression and cytokine secretion profiles, ILCs have been considered as the innate phenocopy of CD4 Th cells. Here, we explored the transcriptome of circulating human ILC subsets as opposed to CD4 Th cell subsets. We describe transcriptomic differences between total ILCs and total CD4 Th cells, as well as between paired innate and adaptive cell subsets (ILC1 vs. Th1; ILC2 vs. Th2; and ILC3 vs. Th17 cells). In particular, we observed differences in expression of genes involved in cell trafficking such as CCR1, CCR6 and CXCR3, innate activation and inhibitory functions, including CD119, 2B4, TIGIT, and CTLA-4, and neuropeptide receptors, such as VIPR2. Moreover, we report for the first time on distinct expression of long noncoding RNAs (lncRNAs) in innate vs. adaptive cells, arguing for a potential role of lncRNA in shaping human ILC biology. Altogether, our results point for unique, rather than redundant gene organization in ILCs compared to CD4 Th cells, in regard to kinetics, fine-tuning and spatial organization of the immune response

    HbA1c in Nondiabetic Dutch Infants Aged 8–12 Months: The GECKO-Drenthe birth cohort study

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    OBJECTIVE-An international committee of experts recommended using HbA(1c) for diagnostic testing for diabetes. Little is known about normal values of HbA(1c) in infants. The aim of this study is to describe the distribution of HbA(1c) in 8- to 12-month-old nondiabetic infants. RESEARCH DESIGN AND METHODS-HbA(1c) was measured in 86 infants participating in the Groningen Expert Center for Kids with Obesity (GECKO)-Drenthe birth cohort study. Anthropometric measurements were performed at Well Baby Clinics. Data on parents and children were collected prospectively using questionnaires. RESULTS-HbA(1c) was normally distributed with a mean (SD) HbA(1c) level of 5.38% (0.24), range 4.8-6.0% or 35.29 mmol/mol (2.65), range 29.1-42.1 mmol/mol. Age, sex, birth weight, duration of breastfeeding, anthropometric measurements, and maternal BMI were not associated with HbA(1c). CONCLUSIONS-We found a normal distribution of HbA(1c) with a relatively high mean HbA(1c) of 5.38%. No significant association between risk factors for type 2 diabetes and HbA(1c) levels was found

    A Practical Introduction to Mechanistic Modeling of Disease Transmission in Veterinary Science.

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    Computer-based disease spread models are frequently used in veterinary science to simulate disease spread. They are used to predict the impacts of the disease, plan and assess surveillance, or control strategies, and provide insights about disease causation by comparing model outputs with real life data. There are many types of disease spread models, and here we present and describe the implementation of a particular type: individual-based models. Our aim is to provide a practical introduction to building individual-based disease spread models. We also introduce code examples with the goal to make these techniques more accessible to those who are new to the field. We describe the important steps in building such models before, during and after the programming stage, including model verification (to ensure that the model does what was intended), validation (to investigate whether the model results reflect the modeled system), and convergence analysis (to ensure models of endemic diseases are stable before outputs are collected). We also describe how sensitivity analysis can be used to assess the potential impact of uncertainty about model parameters. Finally, we provide an overview of some interesting recent developments in the field of disease spread models

    The contribution of coaching and mentoring to the development of participants in entrepreneurial development programmes

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    CITATION: van Coller-Peter, S. & Cronjé, J. 2020. The Contribution of Coaching and Mentoring to the Development of Participants in Entrepreneurial Development Programmes. International Journal of Evidence Based Coaching and Mentoring, 18(2):51-67. doi:10.24384/bg74-fc70The original publication is available at https://radar.brookes.ac.uk/radar/items/b6bb9783-f20a-44f6-9e07-f9bdf4437eb1/1/A significant need among small and medium enterprises is the transfer of skills, specifically business acumen, through mentorship and coaching. Despite the similarities between coaching and mentoring, it is important to understand the different contributions that coaching and mentoring can make to the development of entrepreneurs. The findings of this qualitative study acknowledge the different contributions of coaching and mentoring to participants at the University of Stellenbosch Business School’s (USB) Small Business Academy. It is therefore recommended that coaching and mentoring should be defined separately and differently within the context of the USB Small Business Academy’s Development Programme and similar entrepreneurial development programmes.https://radar.brookes.ac.uk/radar/items/7eea93d3-a316-4242-be40-0c9b11997bd4/1/Publishers versio
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