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Huina Gao,1,* Yijun Song,2,* Kun Liu,1,* Xinyuan Lu,3 Jiacheng Shen,2 Sulan Wei,2 Hongni Jiang,1,2 Nuo Xu2 1Department of Pulmonary Medicine, Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, People’s Republic of China; 2Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, People’s Republic of China; 3School of Public Health, Key Laboratory of Public Health Safety, Ministry of Education, Fudan University, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Nuo Xu, Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, People’s Republic of China, Email xu.nuo@zs-hospital.sh.cn; Hongni Jiang, Department of Pulmonary Medicine, Xiamen Branch, Zhongshan Hospital, Fudan University, 668 Jinhu Road, Xiamen, 361015, People’s Republic of China, Email jiang.hongni@zs-hospital.sh.cnPurpose: Cigarette smoking is the most recognized risk factor of chronic obstructive pulmonary disease (COPD) in China. However, there are no studies analyzing the impact of different smoking behaviors on pulmonary function and pulmonary hypertension (PH) among Chinese male patients with COPD.Patients and Methods: Chinese male smokers with COPD performed pulmonary function tests. Clinical characteristics, smoking behavior features, spirometry and echocardiographic results were compared between the two groups stratified by initial smoking age (18 years old) or complicated PH.Results: The early-smoking group had more respiratory symptoms, more severe smoking behavior, worse pulmonary function with lower FEV1%pre (38.5% vs 70.2%) and FEV1/FVC% (47.5% vs 63.8%), and higher systolic pulmonary artery pressure (sPAP: 38.6 vs 33.9 mmHg) than the late-smoking group. Initiating smoking before adulthood was an independently contributing factor of ventilatory dysfunction and Global Initiati

Revenue management (RM) is one area of research and practice that has gained significant attention in the past decade. The practice originated in the airline industry, where the idea was to maximize revenues obtained from a fixed amount of resources through differentiation/segmentation and strategic use of pricing and capacity. While many of the research models take into account uncertainty, the uncertainty is modeled using random variables and known probability distributions, which is often difficult to estimate and prone to error for a variety of reasons. For instance, demand patterns can fluctuate substantially from the past,and characterizing demand from censored data is challenging. This dissertation focuses on the multifare single resource (leg) problem in RM.We consider the "limited information" case where the demand information available consists of lower and upper bounds rather than a characterization of a particular probability distribution or stochastic process. We first investigate the value of the amount and type of information used in solving the single-leg RM problem. This is done via extensive computational experiments. Our results indicate that new robust methods using limited information perform comparably to other well-known procedures. These robust policies are very effective and provide consistent results, even though they use no probabilistic information. Further, robust policies are less prone to errors in modeling demand. Results of our preliminary computations justify the use of robust methods in the multi-fare single-leg problem. We next apply this distribution-free approach to a setting where progression of demand is available through time-dependent bounds. We do not make any further assumptions about the demand or the arrival process beyond these bounds and also do not impose a risk neutrality assumption. Our analytical approach relies on competitive analysis of online algorithms, which guarantee a certain performance level under all poss