1,191 research outputs found

    A Balancing Domain Decomposition by Constraints Preconditioner for a C\u3csup\u3e0\u3c/sup\u3e Interior Penalty Method

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    Consider the following weak formulation of a fourth order problem on a bounded polygonal domain Ω in R :

    TRAO Survey of Nearby Filamentary Molecular clouds, the Universal Nursery of Stars (TRAO FUNS) I. Dynamics and Chemistry of L1478 in the California Molecular Cloud

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    "TRAO FUNS" is a project to survey Gould Belt's clouds in molecular lines. This paper presents its first results on the central region of the California molecular cloud, L1478. We performed On-The-Fly mapping observations using the Taedeok Radio Astronomy Observatory (TRAO) 14m single dish telescope equipped with a 16 multi-beam array covering \sim1.0 square degree area of this region using C18^{18}O (1-0) mainly tracing low density cloud and about 460 square arcminute area using N2_{2}H+^{+} (1-0) mainly tracing dense cores. CS (2-1) and SO (3221)(3_{2}-2_{1}) were also used simultaneously to map \sim440 square arcminute area of this region. We identified 10 filaments by applying the dendrogram technique to the C18^{18}O data-cube and 8 dense N2_{2}H+^{+} cores by using {\sc FellWalker}. Basic physical properties of filaments such as mass, length, width, velocity field, and velocity dispersion are derived. It is found that L1478 consists of several filaments with slightly different velocities. Especially the filaments which are supercritical are found to contain dense cores detected in N2_{2}H+^{+}. Comparison of non-thermal velocity dispersions derived from C18^{18}O and N2_{2}H+^{+} for the filaments and dense cores indicates that some of dense cores share similar kinematics with those of the surrounding filaments while several dense cores have different kinematics with those of their filaments. This suggests that the formation mechanism of dense cores and filaments can be different in individual filaments depending on their morphologies and environments.Comment: 25 pages, 15 figures, accepted for publication in Ap

    IAU Commission C3 (History of Astronomy): Triennial Report, 2018–2021

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    IAU Commission C3 (History of Astronomy) started in 2015 as a natural continuation of the previous IAU Commission 41 for History of Astronomy which was established in 1948 and which was extremely successful in supporting research on the history of astronomy, organizing and sponsoring workshops and conferences, promoting research collaborations, forming specialist working groups and fostering the publication of members' research (see Kochhar et al., 2015)

    Inducible and Reversible Clock Gene Expression in Brain Using the tTA System for the Study of Circadian Behavior

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    The mechanism of circadian oscillations in mammals is cell autonomous and is generated by a set of genes that form a transcriptional autoregulatory feedback loop. While these “clock genes” are well conserved among animals, their specific functions remain to be fully understood and their roles in central versus peripheral circadian oscillators remain to be defined. We utilized the in vivo inducible tetracycline-controlled transactivator (tTA) system to regulate Clock gene expression conditionally in a tissue-specific and temporally controlled manner. Through the use of Secretogranin II to drive tTA expression, suprachiasmatic nucleus– and brain-directed expression of a tetO::Clock(Δ19) dominant-negative transgene lengthened the period of circadian locomotor rhythms in mice, whereas overexpression of a tetO::Clock(wt) wild-type transgene shortened the period. Low doses (10 μg/ml) of doxycycline (Dox) in the drinking water efficiently inactivated the tTA protein to silence the tetO transgenes and caused the circadian periodicity to return to a wild-type state. Importantly, low, but not high, doses of Dox were completely reversible and led to a rapid reactivation of the tetO transgenes. The rapid time course of tTA-regulated transgene expression demonstrates that the CLOCK protein is an excellent indicator for the kinetics of Dox-dependent induction/repression in the brain. Interestingly, the daily readout of circadian period in this system provides a real-time readout of the tTA transactivation state in vivo. In summary, the tTA system can manipulate circadian clock gene expression in a tissue-specific, conditional, and reversible manner in the central nervous system. The specific methods developed here should have general applicability for the study of brain and behavior in the mouse

    Expression of TLR2, TLR4, and TLR9 in dermatomyositis and polymyositis

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    The aim of this study was to investigate the expressions of Toll-like receptor (TLR) 2, TLR4, TLR9, and their correlations with the expression of cytokines that are associated with activation of CD4+ T cells and inflammation including interferon γ (IFNγ), interleukin 4 (IL4), interleukin 17 (IL17), and tumor necrosis factor α (TNFα) in muscle tissues of patients with dermatomyositis (DM) and polymyositis (PM). The expressions of TLR2, TLR4, TLR9, IFNγ, IL4, IL17, and TNFα were measured by real-time reverse transcription–polymerase chain reaction in muscle tissues from 14 patients with DM and PM (nine patients with DM, five patients with PM) and three controls. The expressions of TLR2, TLR4, and TLR9 were also localized with immunohistochemistry. The expression levels of TLR2, TLR4, TLR9, IFNγ, IL4, IL17, and TNFα were significantly high in patients with DM and PM compared with those in the controls, and the expression levels of TLR4 and TLR9 had significant positive correlations with the expressions of IFNγ, IL4, IL17, and TNFα. Immunohistochemistry showed that TLR2, TLR4, and TLR9 were expressed by infiltrating cells of perimysium in DM, whereas they were expressed by infiltrating cells of endomysium in PM. These results suggest that the involvement of TLR4 and TLR9 in immunopathogenesis of DM and PM might be connected with activation of CD4+ T cells

    Retinol binding protein-4 elevation is associated with serum thyroid-stimulating hormone level independently of obesity in elderly subjects with normal glucose tolerance

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    CONTEXT: Elevated levels of retinol binding protein-4 (RBP4) are positively correlated with insulin resistance, obesity, diabetes mellitus, and cardiovascular disease (CVD). Subclinical hypothyroidism (SCH) has also been associated with CVD; however, the factors linking SCH to CVD are not clear. OBJECTIVE: The objective of the study was to evaluate risk factors for CVD in elderly patients grouped according to thyroid function. DESIGN: 217 subjects (> or =65 yr old) were randomly selected from a population and allocated to a euthyroid group (n = 177) and an SCH group (n = 40) on the basis of plasma concentrations of TSH and free T(4). We included subjects with normal glucose tolerance by a 75-g oral glucose tolerance test and subjects with impaired fasting glucose. We measured anthropometric parameters, levels of fasting glucose and insulin, hemoglobin A(1c), adiponectin, RBP4, lipid profiles, total body fat content, and the area of sc and visceral fat. RESULTS: The SCH group had higher RBP4 levels than the euthyroid group, irrespective of body mass index and fat content. Subcutaneous and visceral fat areas and total body fat percentage did not differ between groups and were not correlated with RBP4 level. Other CVD risk factors did not differ between groups. RBP4 level was positively correlated with TSH level (r = 0.241, P = 0.001) after adjustment for age, sex, and body mass index. CONCLUSIONS: Plasma RBP4 levels were associated with SCH independent of obesity in elderly subjects with normal glucose tolerance, indicating that RBP4 level could be used as an index of CVD risk in SCH
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