Nocturnal asthma: mechanisms and treatment Patients with asthma often wheeze at night and in the early morning.This symptom may prove difficult to treat,1 2 but it is important: sudden death in asthma tends to occur at these
Abstract We present the Three-mm Ultimate Mopra Milky Way Survey, a new mm-wave molecular-line mapping survey of the southern Galactic Plane, and its first data releases and science results. ThrUMMS maps a 60° × 2° sector of our Galaxy's fourth quadrant, using a combination of fast mapping techniques with the Mopra radio telescope, simultaneously in the J = 1→0 lines of 12 CO, 13 CO, C 18 O, and CN near 112 GHz, at 1′.2 and 0.3 km s −1 resolution, with 1.2 K/ch sensitivity for 12 CO and 0.7 K/ch for the other transitions. The calibrated data cubes from these observations are made freely available to the community on the ThrUMMS website, http://www.astro.ufl.edu/thrumms , after processing through our pipeline. Here, we summarise the first science results, on global variations in the iso-CO line ratios and on a detailed multiwavelength study of the GMCs near l =333°.
Aims A randomized trial was performed to assess the safety and efficacy of a laser guidewire, in the treatment of chronic coronary occlusions. Methods and Results In 18 European centres, 303 patients with a chronic coronary occlusion were randomized to treatment with either the laser guidewire (n=144) or conventional guidewires (mechanical guidewire, n=159). The primary end-point of the study was treatment success, defined as reaching the true lumen distal to the occlusion by the allocated wire within 30min of fluoroscopic time: laser guidewire vs mechanical guidewire; 52·8% (n=76) vs 47·2% (n=75), P=0·33. Serious adverse events following the initial guidewire attempt were 0% (laser guidewire) and 0·6% (mechanical guidewire), respectively. Angioplasty (performed following successful guidewire crossing) was successful in 179 patients (91%, laser guidewire n=79, mechanical guidewire n=100), followed by stent implantation in 149 (79%). At the 6-month angiographic follow-up, the difference in binary restenosis rate (laser guidewire vs mechanical guidewire; 45·5% vs 38·3 %, P=0·72) or reocclusion rate (25·8% vs 16·1%, P=0·15) did not reach statistical significance. At 1, 6 and 12 months, angina and event-free survival were 69%, 35% and 24% (laser guidewire) vs 74%, 40% and 31% (mechanical guidewire). Conclusion Although laser guidewire technology was safe, the increase in crossing success did not reach statistical significance.
Development of suitable methods for the quantification of the proliferative response of airway smooth muscle (ASM) cells in culture will assist the investigation of the cellular mechanisms underlying the hyperplasia and hypertrophy of ASM as seen in asthmatic airways. In this study, two rapid and simple colorimetric assays have been modified to enable the growth of human bronchial and rabbit tracheal smooth muscle in culture to be assessed. One method depends upon the reduction by living cells of the tetrazolium salt MTT to form a blue formazan product, whereas the other relies on rapid binding of the dye Coomassie brilliant blue to protein at acidic pH. Experiments demonstrated the validity of both assays in quantifying the proliferative response of cultured human and rabbit ASM cells. The increase in optical density observed for each assay correlated directly, throughout the duration of culture, with the increase in cell number determined by hemocytometry in human and rabbit ASM cells proliferating in response to fetal calf serum (1.25 to 10%). This relationship held also for rabbit tracheal ASM cells proliferating in response to the heterodimer of platelet-derived growth factor (1 to 50 ng/ml). Application of these methods to adherent proliferating cultures of human and rabbit ASM cells demonstrated their adaptability to the generation of growth curves in response to serum and to a defined growth factor. These methods allow both total cellular protein and proliferation to be estimated in human and rabbit ASM cells in culture, using assays that are rapid, reproducible, inexpensive, and easy to perform while negating the use of radioisotopes. It is intended that these additional methods should be useful in delineating some of the mechanisms that might contribute to the proliferative response of these cells — particularly since there has been a resurgence in interest in culturing smooth muscle cells derived from the airways.
Abstract The behaviour and design of homogeneous and hybrid high strength steel (HSS) beams are addressed in the present study. Six in‐plane three‐point bending tests on three different welded I‐sections were first conducted. Following the experimental investigation, a finite element (FE) modelling programme was performed, which included a validation study confirming the accuracy of the developed FE models in replicating the flexural behaviour of HSS welded I‐section beams, and a parametric study generating additional FE data on HSS welded I‐section beams over a broader range of cross‐sectional slendernesses, steel grades and loading configurations. Then, the suitability of the current Eurocode 3 cross‐section slenderness limits for HSS homogeneous and hybrid welded I‐sections in bending were evaluated. It is shown that the current Eurocode Class 2 and Class 3 slenderness limits are suitable for the classification of the outstand flange (in compression) and internal web (in bending) elements of both HSS homogeneous and hybrid welded I‐sections subjected to major axis bending, while stricter Class 1 slenderness limits are considered necessary to achieve sufficient rotation capacity for plastic design. The findings indicate that plastic design can be used for HSS structures, provided the proposed stricter Class 1 slenderness limits are employed. Further work is underway to develop advanced design approaches using second‐order inelastic analysis with strain limits for HSS welded I‐section members.
Theophylline can still have a role in the management of stable chronic obstructive pulmonary disease (COPD), but its use remains controversial, mainly due to its narrow therapeutic window. Doxofylline, another xanthine, is an effective bronchodilator and displays a better safety profile than theophylline. Therefore, we performed a quantitative synthesis to compare the efficacy and safety profile of different xanthines in COPD. The primary end-point of this meta-analysis was the impact of xanthines on lung function. In addition, we assessed the risk of adverse events by normalising data on safety as a function of person-weeks. Data obtained from 998 COPD patients were selected from 14 studies and meta-analysed using a network approach. The combined surface under the cumulative ranking curve (SUCRA) analysis of efficacy (change from baseline in forced expiratory volume in 1 s) and safety (risk of adverse events) showed that doxofylline was superior to aminophylline (comparable efficacy and significantly better safety), bamiphylline (significantly better efficacy and comparable safety), and theophylline (comparable efficacy and significantly better safety). Considering the overall efficacy/safety profile of the investigated agents, the results of this quantitative synthesis suggest that doxofylline seems to be the best xanthine for the treatment of COPD.
No abstract is provided for this article.
Honeycomb structures have a wide range of applications, from medical implants to industrial components. In addition, honeycombs play a critical role when passive protection is required due to their low density and high energy absorption capabilities. With the transition of additive manufacturing from a rapid prototyping approach to a manufacturing process, this technology has recently offered designers and manufacturers the ability to fabricate and modify lattice structures such as honeycombs. The current study presents the application of laser powder bed fusion, a common additive manufacturing process for producing industrial metal components, for fabricating metal honeycombs. In addition, this study examines three modified designs that can only be practically fabricated using additive manufacturing and compares them with conventional honeycombs. For this purpose, quasi-static and dynamic compression tests are conducted to evaluate and compare the performance of the honeycomb structures. The results show that the structures produced by additive manufacturing have acceptable performance compared to conventional honeycomb structures, and laser powder bed fusion can be considered to be a reliable manufacturing method for honeycomb production. Furthermore, the honeycombs produced according to the modified designs generally outperformed their counterparts made from the typical hexagonal cells. Ultimately, the use of triangular cells as a design modification is proposed to produce honeycombs with promising performance characteristics in all of their principal axes and under various pressure scenarios, from quasi-static to dynamic loading rates. Finally, this study also investigates the applicability of a newly developed maraging steel for additive manufacturing of honeycombs. Microstructural analysis and quasi-static tensile tests have confirmed the material properties for this purpose.
