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Background: Endoscopic submucosal dissection (ESD) treatment of early esophageal cancer is effective and safe. It is currently the first-line treatment for early esophageal cancer. However, a common side effect is the development of esophageal strictures after ESD. This study was designed to identify the risk factors for esophageal stricture development and to predict its occurrence after ESD.Methods: In this retrospective study, 150 consecutive patients with early esophageal cancer treated with ESD at Daping Hospital, Chongqing, were enrolled between January 2016 and December 2020. Data on patient demographics, esophageal tumor characteristics, procedure-related factors, and postoperative situations were collected. We identified independent risk factors of esophageal stricture formation using univariate analysis and multivariate logistic regression. The predictive probability was obtained after multivariate logistic analysis. In addition, patients were divided into six groups based on these risk factors and the rate of esophageal stricture in each group was analyzed.Results: The postoperative esophageal stricture rate was 14% (21/150). Tumor location (OR = 5.655, 95% CI: 1.245-25.691, P = 0.025) and circumferential resection range (OR = 16.113, 95% CI: 4.294-60.466, P < 0.001) are independent risk factors for the development of esophageal strictures. According to predictive probability analysis and the rates of stricture in six groups, we developed a possible flow chart to predict stricture formation.Conclusions: Tumor location and circumferential resection range are reliable risk factors to predict the occurrence of esophageal strictures. Our prediction flow chart suggests that tumors with a circumferential resection range of 1/2-3/4 and located above the upper thoracic segment or a circumferential resection range of > 3/4 have a high risk of postoperative stricture. Thus, timely and effective preventive measures should be taken in these patients following ESD. [ABSTRACT FROM AUTHOR]

• The estimated prevalence of sarcopenia in RA was 31%, without significant differences between various living area and diagnostic modalities. • Disease duration, DAS28 and HAQ were predictors of sarcopenia development in patients with RA. • Functional limitation, CRP and RF seropositivity were identified as additional risk factors. Sarcopenia is an ever-increasingly recognized entity in aging or chronically-ill individuals. A recent surge of researches came out on sarcopenia in rheumatoid arthritis (RA). However, the results varied widely. We tried to assess the prevalence of and associated factors with sarcopenia in patients with RA. We searched the investigations dealing with the prevalence of and associated factors with sarcopenia in RA from PubMed, EMBASE, CENTRAL, EBSCOhost, Airiti Library, CEPS, CNKI and J-STAGE from the inception to January 11, 2020. Effects regarding prevalence and associated factors were extracted and evaluated by random-effects model. Sensitivity analysis was also performed. Seventeen studies containing 3,140 RA subjects were identified. After exclusion of outliers, the pooled prevalence of sarcopenia was 31%. Neither ongoing-study districts nor diagnostic modalities affected prevalence significantly. Any associated factors being mentioned in at least two publications were analyzed, yielding functional limitation (Steinbrocker stage III/IV), high CRP and RF seropositivity as the significant risk factors. Based on disease durations, we carried out meta-regression and found DAS28 and HAQ are predictive models. There was no alteration in the interpretation of results from sensitivity analysis after removal of any studies skewed in sampling distribution. The prevalence of sarcopenia in patients with RA is high, compared to that in general counterparts. Disease duration rather than age, residing area or diagnostic modalities influences sarcopenia development; DAS28 and HAQ predict occurrence. High index of suspicion to facilitate early detection of sarcopenia in RA patients is important. [ABSTRACT FROM AUTHOR]

Highlights • We demonstrate a dual-wavelength and dual-pulse Yb-doped fiber with a Tm-Ho co-doped fiber as saturable absorber. • The pulse at 1064 nm is generated via SA-induced self Q-switching. • The pulse at 2127.7 nm is generated by gain-switching with the laser at 1064 nm as the pump for the Tm-Ho co-doped fiber. • The pulse duration of the laser at 1064 nm can reach up to 1.4 μs. Abstract We demonstrate a dual-wavelength and dual-pulse Yb-doped fiber laser with a Tm-Ho co-doped fiber as saturable absorber (SA). The wavelength of the first pulse in the dual-pulsing output is at 1064 nm generated via SA-induced self Q-switching and the second pulse is at 2127.7 nm and generated by gain-switching with the laser at 1064 nm as the pump for the Tm ions in the Tm-Ho co-doped fiber and thus induced stimulated emission. With the increases of the pump power, the pulse duration of the two pulses is decreased depending on the level of the pump. The pulse duration of the laser at 1064 nm decreases from 1.4 μs to 296 ns when the pump power increases from 275 mW to 475 mW, while the pulse duration at 2127.7 nm is reduced from 440 ns to 246 ns when the pump increases from 300 mW to 475 mW. Accordingly, the repetition rate is decreased from 17.4 kHz to 6.8 kHz. The experimental result shows that Tm-Ho co-doped fiber is an excellent candidate for SA-induced Q-switching at 1064 nm. [ABSTRACT FROM AUTHOR]

Abstract We demonstrate an all-fiber passively mode-locked Tm-Ho co-doped fiber laser based on a GaAs saturable absorber (SA) fiber laser at 1875.2 nm. With a 10% output coupler, the fiber laser outputs 1.13 MHz, 634 ps and 25 nJ pulses at 1875.2 nm with a 3 dB-bandwidth of 18.4 nm. The Q-switched mode-locking (QML), the mode-locking at fundamental repetition rate (FRR) and the mode-locking at second harmonic of repetition rate (SHRR) are also observed with the increase of the pump power. The main reason of the SHRR is soliton pulse energy quantization effect. [ABSTRACT FROM AUTHOR]

This work presents the experimental and theoretical investigations on the mechanism of laser-induce cracks in ice. The laser-induced thermal gradient would generate significant thermal stress and lead to the cracking without thermal melting in the ice. The crack density induced by a pulsed laser in the ice critically depends on the laser scanning speed and the size of the laser spot on the surface, which determines the laser power density on the surface. A maximum of 16 cracks within an area of 17 cm × 10 cm can be generated when the laser scanning speed is at 10 mm/s and the focal point of the laser is right on the surface of the ice with a laser intensity of ∼4.6 × 10 7  W/cm 2 . By comparing the infrared images of the ice generated at various experimental conditions, it was found that a larger temperature gradient would result in more laser-induced cracks, while there is no visible melting of the ice by the laser beam. The data confirm that the laser-induced thermal stress is the main cause of the cracks created in the ice. [ABSTRACT FROM AUTHOR]