55 research outputs found

    Investigation of the impact of roof configurations on the wind and thermal environment in football stadiums in hot climates

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    The present study provides an analysis of existing literature encompassing the wind and thermal analysis of football stadia, and how both can be manipulated through the modification of roof geometry. It introduces the potential for cooling strategies to create an internal environment capable of hosting elite-level international football in a hot climate. The motivation for the study stems from an absence of existing literature focussing on thermal flow in hot conditions for stadia and the requirement to investigate the hosting capabilities of Qatar for the 2022 FIFA World Cup. Stadium design plays a crucial role in determining the success of the tournament not only through the month-long event, but also with the legacy it leaves afterwards. To carry out the analysis, Computational Fluid Dynamics (CFD) simulations were conducted in an effort to produce internal conditions that satisfy official FIFA guidelines on optimal playing conditions in terms of wind and temperature distribution. These are ran on a model validated against existing literature to ensure accuracy, but considering the potential for error between model generations. The conclusions drawn suggest that a downward-pitched, large-radius retractable roof subsidised by the introduction of a mechanical system to create a cooling strategy reduces the external temperature down to 23 °C, with wind velocities not exceeding 4 m/s. Reinforced by results, these desired playing conditions can be achieved by closing the roof to precondition the stadium before an event, with the roof then retracted to ensure compliance with FIFA guidelines. The results from the present study can be a component in achieving a sustained positive legacy for the upcoming FIFA World Cup

    An airway epithelial IL-17A response signature identifies a steroid-unresponsive COPD patient subgroup

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    BACKGROUND. Chronic obstructive pulmonary disease (COPD) is a heterogeneous smoking-related disease characterized by airway obstruction and inflammation. This inflammation may persist even after smoking cessation and responds variably to corticosteroids. Personalizing treatment to biologically similar "molecular phenotypes" may improve therapeutic efficacy in a COPD. IL-17A is involved in neutrophilic inflammation and corticosteroid resistance, and thus may be particularly important in a COPD molecular phenotype. METHODS. We generated a gene expression signature of IL-17A response in bronchial airway epithelial brushings from smokers with and without COPD (n = 238) , and validated it using data from 2 randomized trials of IL-17 blockade in psoriasis. This IL-17 signature was related to clinical and pathologic characteristics in 2 additional human studies of COPD: (a) SPIROMICS (n = 47), which included former and current smokers with COPD, and (b) GLUCOLD (n = 79), in which COPD participants were randomized to placebo or corticosteroids. RESULTS. The IL-17 signature was associated with an inflammatory profile characteristic of an IL-17 response, including increased airway neutrophils and macrophages. In SPIROMICS the signature was associated with increased airway obstruction and functional small airways disease on quantitative chest CT. In GLUCOLD the signature was associated with decreased response to corticosteroids, irrespective of airway eosinophilic or type 2 inflammation. CONCLUSION. These data suggest that a gene signature of IL-17 airway epithelial response distinguishes a biologically, radiographically, and clinically distinct COPD subgroup that may benefit from personalized therapy

    Global urban environmental change drives adaptation in white clover

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Some notes on type material of moas (Aves: Dinornithidae)

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    Volume: 113Start Page: 257End Page: 25
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