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No abstract is provided for this article.

Wire arc additive manufacturing (WAAM), a method of metal 3D printing, has the capacity to create large scale elements suitable for construction applications with a high degree of design freedom and structural efficiency. There is currently however a lack of fundamental experimental data on the material and structural performance of such elements. Towards addressing this limitation, the tensile behaviour of WAAM high strength steel produced using different printing strategies is the focus of the present study. WAAM steel plates and tubular tension members manufactured with different interpass temperatures and toolpaths using ER110S-G welding wire were examined. A total of 60 tensile coupons, consisting of 40 as-built and 20 machined specimens, and 8 as-built circular hollow section (CHS) tension members, were tested. The examined WAAM materials were found to exhibit very little anisotropy, corroborated by a nearly homogeneous crystallographic texture observed by microstructural analysis, while the inherent surface undulations were shown to result in a varying degree of reduction in the material stiffness, strength and ductility at different angles to the print layer orientation. The different printing strategies led to varying surface geometries; combined with different interpass temperatures, they also resulted in different thermal histories and thus different mechanical properties. The tension members showed good structural resistance, but a considerable reduction in ductility compared to the coupon tests, due to the greater geometric variability and manufacturing defects.

Abstract Many patients with persistent asthma can be controlled with inhaled corticosteroids (ICS). However, a considerable proportion of patients remain symptomatic, despite the use of ICS. We present systematically evidence that supports the different treatment options. A literature search was made of Medline/PubMed to identify randomised and blinded trials. To demonstrate the benefit that can be obtained by increasing the dose of ICS, dose-response studies with at least three different ICS doses were identified. To demonstrate whether more benefit can be obtained by adding long-acting β 2 -agonist (LABA), leukotriene antagonist (LTRA) or theophylline than by increasing the dose of ICS, studies comparing these options were identified. Thirdly, studies comparing the different "add-on" options were identified. The addition of a LABA is more effective than increasing the dose of ICS in improving asthma control. By increasing the dose of ICS, clinical improvement is likely to be of small magnitude. Addition of a LTRA or theophylline to the treatment regimen appears to be equivalent to doubling the dose of ICS. Addition of a LABA seems to be superior to an LTRA in improving lung function. However, addition of LABA and LTRA may be equal with respect to asthma exacerbations. However, more and longer studies are needed to better clarify the role of LTRAs and theophylline as add-on therapies.

Several volatile organic compounds have been identified in exhaled breath in healthy subjects and patients with respiratory diseases by gas chromatography/mass spectrometry. Identification of selective patterns of volatile organic compounds in exhaled breath could be used as a biomarker of inflammatory lung diseases. An electronic nose (e-nose) is an artificial sensor system that generally consists of an array of chemical sensors for detection of volatile organic compound profiles (breathprints) and an algorithm for pattern recognition. E-noses are handheld, portable devices that provide immediate results. E-noses discriminate between patients with respiratory disease, including asthma, COPD and lung cancer, and healthy control subjects, and also among patients with different respiratory diseases. E-nose breathprints are associated with airway inflammation activity. In combination with other ‘omics’ platforms, e-nose technology might contribute to the identification of new surrogate markers of pulmonary inflammation and subphenotypes of patients with respiratory diseases, provide a molecular basis to a personalized pharmacological treatment, and facilitate the development of new drugs.

Background Allergens from rats, mice, guinea pigs or rabbits cause up to 30% of exposed persons to develop specific immunoglobulin E (IgE) responses. Laboratory animal allergy (LAA) is among the highest occupational risks for asthma in the UK. Elevated levels of nitric oxide (NO) are found in exhaled breath in asthma. In LAA symptoms may progress from conjunctivitis, rhinitis to asthma. Health surveillance aims to detect early sensitization. Objective To assess whether an association exists between LAA and exhaled NO. Methods A cross‐sectional study was performed in 39 laboratory workers undergoing LAA health surveillance. Volunteers completed two health questionnaires, had skin‐prick tests, spirometry, total IgE and RAST tests. Exhaled and nasal NO was measured by chemiluminescence analyser (LR2000, Logan Research, Rochester, UK). Results There were 23 asymptomatic subjects (mean age 29.53 yearss) and 16 symptomatic subjects (29.63 yearss, P = 0.95); 9 early LAA, seven LAA asthma. Exhaled NO was raised in those with LAA symptoms 17.97 ppb ± 1.24 (mean ± SEM ) compared with asymptomatics 6.08 ppb ± 1.15, P < 0.05. A trend of increased NO by allergic status was observed; asymptomatic, to early LAA, to asthma. One‐way analysis of variance compared differences between groups (F ratio 13.93, P < 0.001). Symptomatic subjects also had raised nasal NO, vs asymptomatic subjects (mean difference 378 ppb, P < 0.05). A trend was again observed by allergic status (F ratio 5.28, P = 0.01). Conclusion Raised NO levels in LAA increasing with symptom severity suggest NO may prove a useful additional tool in monitoring for LAA, and possibly the response to exposure reduction or allergy due to other respiratory sensitizers.

No abstract is provided for this article.

We investigated the effect of Ba 679 BR, a novel long-acting antimuscarinic agent, on cholinergic neural responses in guinea pig and human airways. Ba 679 BR, atropine, and ipratropium bromide inhibited electrical field stimulation (EFS)-induced contraction with IC50 values of 0.17, 0.74, and 0.58 nM, respectively, in guinea pig trachea. Ba 679 BR had a slower onset and longer duration of action than atropine or ipratropium bromide (the times required to attain 50% of the maximum response were 34.8, 3.8, and 7.6 min, respectively, and the times required for 50% recovery of the response were 540, 31.6, and 81.2 min, respectively). Ba 679 BR, as well as atropine and ipratropium bromide, facilitated evoked [3H]acetylcholine release (an inhibitory effect on prejunctional muscarinic M2 receptors). The facilitation of acetylcholine release by Ba 679 BR was lost 2 h after washout, however, when there was still complete blockade of cholinergic contractile responses evoked by EFS (an effect on airway smooth muscle M3 receptors), confirming binding studies that suggest that Ba 679 BR shows "kinetic receptor subtype selectivity" for M3 over M2 receptors. The high potency, slow onset, and long duration of action of Ba 679 BR were also observed in human bronchi, suggesting that Ba 679 BR may be a useful drug to provide convenient therapy for patients with obstructive airway disease.