Optical Bloch oscillations and Zener tunneling of Airy beams in ionic-type photonic lattices

<p> We report on the existence of optical Bloch oscillations (OBOs) and Zener tunneling (ZT) of Airy beams in ionic-type photonic lattices with a refractive index ramp. Different from their counterparts in uniform lattices, Airy beams undergoing OBOs show an alternatively switched concave and convex trajectory as well as a periodical revival of input beam profiles. Moreover, the ionic-type photonic lattice established in photorefractive crystal exhibits a reconfigurable lattice structure, which provides a flexible way to tune the amplitude and period of the OBOs. Remarkably, it is demonstrated that the band gap of the lattice can be readily controlled by rotating the lattice inducing beam, which forces the ZT rate to follow two significant different decay curves amidst decreasing index gradient. Our results open up new possibilities for all-optical switching, routing and manipulation of Airy beams. (C) 2016 Optical Society of America</p

Visualization 1: Optical Bloch oscillations and Zener tunneling of Airy beams in ionic-type photonic lattices

Optical Bloch oscillations of Airy beam in lattice 1 Originally published in Optics Express on 08 August 2016 (oe-24-16-18332

Visualization 2: Optical Bloch oscillations and Zener tunneling of Airy beams in ionic-type photonic lattices

Optical Bloch oscillations of Airy beam in lattice 2 Originally published in Optics Express on 08 August 2016 (oe-24-16-18332

An Assessment of the Effect of Bariatric Surgery on Cardiovascular Disease Risk in the Chinese Population Using Multiple Cardiovascular Risk Models

Guangzhong Xu,1,&ast; Zheng Wang,1,&ast; Chengyuan Yu,1,&ast; Buhe Amin,1 Dexiao Du,1 Tianxiong Li,1 Guanyang Chen,2 Liang Wang,2 Zhehong Li,1 Weijian Chen,1 Chenxu Tian,1 Qiqige Wuyun,1 Qing Sang,2 Mingyue Shang,1 Dongbo Lian,1 Nengwei Zhang1 1Surgery Centre of Diabetes Mellitus, Capital Medical University Affiliated Beijing Shijitan Hospital, Beijing, People’s Republic of China; 2Surgery Centre of Diabetes Mellitus, Peking University Ninth School of Clinical Medicine, Beijing, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Nengwei Zhang; Dongbo Lian, Tel +8613801068802 ; +8613681299755, Email [email protected]; [email protected]: Many studies have reported that bariatric surgery may reduce postoperative cardiovascular risk in patient with obesity, but few have addressed this risk in the Chinese population.Objective: To assess the impact of bariatric surgery on cardiovascular disease (CVD) risk in the Chinese population using the World Health Organization (WHO) risk model, the Global risk model, and the Framingham Risk Score.Methods: We retrospectively analyzed data collected on patient with obesity who underwent bariatric surgery at our institution between March 2009 and January 2021. Their demographic characteristics, anthropometric variables, and glucolipid metabolic parameters were assessed preoperatively and at their 1-year postoperative follow-up. Subgroup analysis compared body mass index (BMI) < 35 kg/m2 and BMI ≥ 35 kg/m2, as well as gender. We used the 3 models to calculate their CVD risk.Results: We evaluated 61 patients, of whom 26 (42.62%) had undergone sleeve gastrectomy (SG) surgery and 35 (57.38%) Roux-en-Y gastric bypass (RYGB) surgery. Of the patients with BMI ≥ 35 kg/m2, 66.67% underwent SG, while 72.97% with BMI < 35 kg/m2 underwent RYGB. HDL levels were significantly higher at 12 months postoperatively relative to baseline. When the models were applied to calculate CVD risk in Chinese patients with obesity, the 1-year CVD risk after surgery were reduced lot compared with the preoperative period.Conclusion: Patient with obesity had significantly lower CVD risks after bariatric surgery. This study also demonstrates that the models are reliable clinical tools for assessing the impact of bariatric surgery on CVD risk in the Chinese population.Keywords: obesity, bariatric surgery, CVD, World Health Organization risk model, global risk model, Framingham Risk Scor