6,963 publications from this institution
Abstract In this project, we focus on the analysis of infrared observations of the clumps defined with the Galactic Census of High- and Medium-mass Protostars (ChaMP) (Barnes et al. 2011). We derive line of sight infrared extinction values, star counts and protostar candidates around the molecular gas emission obtained with the Mopra telescope. Then, we examine the correlation between radio and infrared properties of the clumps. For this stage of the project, we use the Vela-Carina and 2MASS catalogs to obtain a preliminary understanding of the final results. For the later stages, we will extract infrared photometry from our deep AAT near-IR and Spitzer 3.6 and 4.5 μm images. With the final deep photometry results, we will compile the properties of individual clusters.
This paper presents a comprehensive numerical study into the in-plane member stability and design of normal and high strength steel (NSS and HSS) non-slender welded I-section beam–columns subjected to compression plus uniaxial bending. Finite element (FE) models were firstly developed to replicate the structural performance of welded I-section beam–columns made of different steel grades, as observed in existing tests collected from the literature. The validated FE models were then employed in a comprehensive parametric study to generate extensive numerical data covering a wide range of cross-section geometries, steel grades, member slendernesses and loading combinations. The numerically obtained data were utilised to evaluate the accuracy of the current design methods set out in the European Standards EN 1993-1-1:2005 and EN 1993-1-12:2007 as well as the American Specification AISC 360-16 for both NSS and HSS non-slender welded I-section beam–columns. The comparisons revealed that the codified design methods yield varying levels of accuracy in predicting the ultimate capacities of welded I-section beam–columns depending on the steel grade. To address this issue, new design proposals that are compatible with the European beam–column design framework have been developed, featuring more accurate yield strength-dependent interaction curves anchored to improved resistance predictions for members subjected to isolated loading scenarios (i.e. the compression and bending end points of the interaction curves). The new design proposals have been found to provide more accurate and consistent resistance predictions than the existing codified design provisions for NSS and HSS non-slender welded I-section members under compression plus uniaxial bending. The reliability of the new proposals has been confirmed through statistical analyses according to EN 1990: 2002.
We present $^{12}$CO, $^{13}$CO, and C$^{18}$O data as the next major release for the CHaMP project, an unbiased sample of Galactic molecular clouds in $l$ = 280$^{\circ}$-300$^{\circ}$. From a radiative transfer analysis, we self-consistently compute 3D cubes of optical depth, excitation temperature, and column density for $\sim$300 massive clumps, and update the $I_{\rm CO}$-dependent CO$\rightarrow$H$_2$ conversion law of Barnes et al (2015). For $N$ $\propto$ $I^p$, we find $p$ = 1.92$\pm$0.05 for the velocity-resolved conversion law aggregated over all clumps. A practical, integrated conversion law is $N_{\rm CO}$ = (4.0$\pm$0.3)$\times$10$^{19}$m$^{-2}$ $I_{\rm CO}^{1.27\pm0.02}$, confirming an overall 2$\times$ higher total molecular mass for Milky Way clouds, compared to the standard $X$ factor. We use these laws to compare the kinematics of clump interiors with their foreground $^{12}$CO envelopes, and find evidence that most clumps are not dynamically uniform: irregular portions seem to be either slowly accreting onto the interiors, or dispersing from them. We compute the spatially-resolved mass accretion/dispersal rate across all clumps, and map the local flow timescale. While these flows are not clearly correlated with clump structures, the inferred accretion rate is a statistically strong function of the local mass surface density $\Sigma$, suggesting near-exponential growth or loss of mass over effective timescales $\sim$30-50 Myr. At high enough $\Sigma$, accretion dominates, suggesting gravity plays an important role in both processes. If confirmed by numerical simulations, this sedimentation picture would support arguments for long clump lifetimes mediated by pressure confinement, with a terminal crescendo of star formation, suggesting a resolution to the 40-yr-old puzzle of the dynamical state of molecular clouds and their low star formation efficiency.
Corticosteroids are the most potent anti-inflammatory agents used to treat chronic inflammatory diseases such as asthma, rheumatoid arthritis, and inflammatory bowel disease. However, some populations of these patients are corticosteroid-insensitive (1-3), and almost of all patients with COPD show a poor response to corticosteroids (4). If the molecular mechanisms for corticosteroid insensitivity are better understood especially in COPD, this may provide insight into the mechanisms of corticosteroid action and allow a rational way to treat these patients whose disease tends to be severe. Elucidation of the cause for the relative lack of corticosteroid response in COPD may have important implications for other chronic inflammatory diseases, such as rheumatoid arthritis and inflammatory bowel disease.
No currently available treatments reduce the progression of COPD or suppress the inflammation in small airways and lung parenchyma. However, several new treatments that target the inflammatory process are in clinical development. A group of specific therapies are directed against the influx of inflammatory cells into the airways and lung parenchyma that occurs in COPD; these include adhesion molecule and chemokine-directed therapy, as well as therapies to combat tumour necrosis factor-alpha and augment interleukin-10. Broad spectrum anti-inflammatory drugs are now in phase III development for COPD, and include phosphodiesterase-4 inhibitors. Other drugs that inhibit cell signalling include inhibitors of p38 mitogen-activated protein kinase, nuclear factor-kappaB and phosphoinositide-3 kinase-gamma. More specific approaches are to give antioxidants, inhibitors of inducible nitric oxide synthase, and leukotriene B4 receptor antagonists. Epidermal growth factor receptor kinase inhibitors and calcium-activated chloride channel inhibitors have potential to combat mucus overproduction. Therapy to inhibit fibrosis is being developed against transforming growth factor-beta1 and protease activated receptor-2. There is also a search for serine proteinase and matrix metalloproteinase inhibitors to prevent lung destruction and the development of emphysema, as well as drugs such as retinoids that may even reverse this process. Effective delivery of drugs to the sites of disease in the peripheral lung is an important consideration, and there is the need for validated biomarkers and monitoring techniques in early clinical studies with new therapies for COPD.
There is increasing evidence that chronic inflammation in asthma is mediated via a network of cytokines emanating from inflammatory and structural cells in the airways. The prominent eosinophilic inflammation that characterizes asthma appears to be orchestrated by cytokines derived from type 2 T-helper (Th2)-like lymphocytes, suggesting that immunosuppressants might be beneficial in the control of asthma. Indeed, one of the critical modes of action of glucocorticoids in controlling asthma may be the suppression of Th2-lymphocyte-derived cytokines, such as interleukin-5 (IL-5). Cyclosporin-A may have a similar immunomodulatory role, but its potential beneficial effects are outweighed by its toxicity, at least when given parenterally. Future immunomodulators need to be more selective, either by means of delivery (inhalation, liposomes) or by a more specific effect on Th2, as opposed to Th1, lymphocytes or their products. Such approaches may include new immunomodulators, such as mycophenolate mofetil, specific cytokine inhibitors (such as interleukin-5 antibodies), endogenous suppressors of Th2 cells (interferon-gamma or interleukin-12), or type 4 phosphodiesterase inhibitors.
Current therapy for asthma with inhaled corticosteroids and long-acting inhaled β<sub>2</sub>-agonists is highly effective, safe, and relatively inexpensive, but many patients remain poorly controlled. Most advances have been through improving these drug classes and a major developmental hurdle is to improve existing drug classes. Major unmet needs include better treatment of severe asthma (which has some similarity to chronic obstructive pulmonary disease), as well as curative therapies for mild to moderate asthma that do not result in the return of symptoms when the treatment is stopped. Several new treatments are in development, but many are specific, targeting a single mediator or receptor, and are unlikely to have a major clinical impact, although they may be effective in specific asthma phenotypes (endotypes). Drugs with more widespread effects, such as kinase inhibitors, may be more effective but have a greater risk of side effects so inhaled delivery may be needed. Several new treatments target the underlying allergic/immune process and would treat concomitant allergic diseases. Improved immunotherapy approaches have the potential for disease modification, although prospects for a cure are currently remote.
No abstract is provided for this article.
We studied the Nobori coronary stent coated with a bioabsorbable polymer and the anti-proliferative agent Biolimus A9 which may reduce neointimal formation.Patients undergoing percutaneous coronary intervention for de novo lesions in up to two native coronary arteries, in 29 centres across Europe, Asia and Australia were randomly (2:1) assigned to receive the Biolimus A9 eluting stent Nobori (85 patients) or paclitaxel eluting stent Taxus(R) (35 patients). The two groups were well matched in baseline characteristics. The primary end point of non-inferiority for in-stent late loss of Nobori stent versus Taxus(R) stent, at 9 months, was reached with the values of 0.15+/-0.27 mm with Nobori stent and 0.32+/-0.33 mm with Taxus(R) stent (p=0.006). Neointimal volume obstruction was 2.2+/-6.0% and 8.9+/-9.2% for Nobori and Taxus(R) stent respectively (p=0.017). The rates of death, myocardial infarction and any target vessel revascularisation at 9 months were 0%, 4.7%, and 7.1% respectively for Nobori stent, and 0%, 8.6% and 14.3% respectively for Taxus(R) stent. Clinically-driven target lesion revascularisation rate was 0% for Nobori stent and 2.9% for Taxus(R) stent. Stent thrombosis rates at 9 months were 0% in both groups.In this trial the Nobori Biolimus A9 eluting stent proved to be safe and effective in reducing neointimal proliferation. The long term safety remains to be confirmed during the extended follow-up period of 5 years.
