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Objective This study was performed to evaluate the outcomes of 25-gauge (25-G) pars plana vitrectomy (PPV) with air tamponade for primary rhegmatogenous retinal detachment (RRD). Methods This retrospective consecutive case series included 126 eyes of 125 patients with primary RRD who underwent 25-G PPV with air tamponade. The patients were followed up for at least 6 months following surgery. The main outcome measures were the primary and final anatomical success rates and postoperative complications. Results The mean age of the 125 patients (80 men and 45 women) was 53.7 ± 10.0 years. The mean follow-up period was 8.3 ± 2.2 months (range, 6–18 months). Twenty-four eyes (19.0%) presented with high myopia, and 13 eyes (10.3%) were pseudophakic. Of the 126 eyes, 37 (29.4%) had inferior breaks, 2 (1.6%) had choroidal detachment, and 86 (68.3%) had macular detachment. The single- and final-operation success rates were 96.0% and 100%, respectively. Postoperative complications included macular hole formation in two eyes. During follow-up, secondary cataract surgery was performed in 27 (23.9%) of the 113 phakic eyes. Conclusion 25-G PPV with air tamponade is effective and safe in treating selected patients with primary RRD with a high anatomical success rate.

Purpose: To evaluate the treatment solutions and effectiveness of intravitreal ranibizumab (RBZ) or conbercept in patients with wet age-related macular degeneration (wAMD) in a real-life setting in China.Methods: The medical records of 368 patients with wAMD who started RBZ or conbercept treatment between 1 May 2014 and 30 April 2018 were evaluated. All patients were defined on fundus angiography at baseline to determine the subtype of AMD (PCV or CNV). We report visual acuity (VA) and central retinal thickness (CRT) measurements at baseline and 12 months.Results: The average number of anti-VEGF injections was 2.1 ± 1.2. The BCVA improvement of these two groups was similar with a difference of 1.00 letter (95% CI: −1.4~3.4, p = 0.8505). At the end of the study, a BCVA increase of at least 5 letters was determined to be a satisfactory efficacy endpoint. Several factors were related to the possible improvement in the satisfactory efficacy endpoint, including female sex (OR 2.07, 95% CI 1.22~3.51), number of injections (OR 1.40, 95% CI 1.12~1.75) and VA change at the first month (OR 13.75, 95% CI 7.41~25.51). Additionally, some factors were related to the possible reduction in the satisfactory efficacy endpoint, including diabetes (OR 0.27, 95% CI 0.10~0.73) and disease history (OR 0.75, 95% CI 0.57~0.98).Conclusion: Our study demonstrates that anti-VEGF drugs can effectively improve BCVA and reduce CRT in AMD patients. Sex, number of injections, VA change at the first month, diabetes and disease history are the most important factors affecting visual acuity.

Objectives To evaluate the foveal avascular zone (FAZ) area in healthy volunteers using optical coherence tomography angiography (OCTA) and identify factors that influence the FAZ. Methods This single-center cross-sectional study included 526 eyes of 263 healthy volunteers who underwent macular scanning by Zeiss OCTA. A linear mixed model was used to investigate the effects of systemic factors (age, sex, blood pressure, height, and weight) and ocular factors (intraocular pressure, biometric parameters, and central macular thickness) on FAZ. Results In total, 520 eyes of 262 healthy volunteers were included in the analysis. The mean volunteer age was 38.59 ± 22.03 years (range, 5–84 years); 124 volunteers were male (47.33%) and 138 volunteers were female (52.67%). The mean FAZ area was 0.30 ± 0.03 mm 2 (95% confidence interval [CI], 0.29–0.31 mm 2 ). Univariate analysis showed that FAZ area was associated with age (β = 0.0011), anterior chamber depth (β = −0.0513), and axial length (β = −0.0202). Multivariate analysis showed that FAZ area was negatively correlated with axial length (β = −0.0181). Conclusions The mean FAZ area in healthy volunteers, measured using Zeiss OCTA, was 0.30 ± 0.03 mm 2 . Furthermore, FAZ area was negatively associated with axial length; this relationship should be considered in clinical practice.

Natural gas is extensively used as a clean energy source in cities and industries; consequently, there are associated risks of accidental explosions. To reduce the hazards associated with natural gas explosions, it is important to study the inherent laws of natural gas blast loads in unconfined spaces and establish load models. Using experiments on natural gas explosions in unconfined spaces, this study demonstrates the influence of natural gas concentrations, propagation distances, and gas volumes upon explosion loads. A new load model was proposed for the overpressure–time history curves of natural-gas explosions in an unconfined space. A comparison with the empirical model indicated that the predictive effect was superior to that of previous models, such as the TNT equivalent model and the TNO multi-energy model.

Due to the influence of many factors, the overpressure–time history load model of vented gas explosions is difficult to describe and is not conducive to further structural design. Based on vented gas explosion test data, this paper obtains three typical overpressure-time history curves and puts forward a new semi-empirical model— double hump model that considers gas concentration and venting pressure, and gives a formula for peak pressure and overpressure–time history model. The scientificity of the model is then verified by the total impulse in the load. The model is able directly reflect the load characteristics, provide reference for calculating key parameters of a vented gas explosion and provide information on the structural response under the load. The model thereby has the potential to help reduce the impact of gas explosion disasters.

The reconstruction of deep in situ environment up to 95 °C and 70 MPa using water is critical for the fidelity testing of deep Earth rocks. The temperature and pressure of the water have strong coupling in such an environment, which makes the control of temperature and pressure very difficult. The paper firstly presents the design of the system of deep in situ environment reconstruction and core transfer (SERCT); secondly, for the problem of high temperature and pressure control, a pressure-temperature (P-T) interpolation control algorithm based on the iso–density P-T curves of water is proposed. A P-T coupling control path is decomposed into two independent interpolation paths: an iso–thermal pressure control and an iso–mass temperature control, which realizes the decoupling control of temperature and pressure. Then, a fuzzy-PID dual mode method is adopted for the pressure control after decoupling, which reduces the overshoot and the dynamic response time of the system. For temperature control, a segmented and grouped electric heating mode is designed to improve the uniformity of the temperature field. A fuzzy PID temperature control algorithm based on grey prediction is proposed to achieve high precision temperature control with small overshoot. Finally, the effectiveness of the proposed methods is verified by experiments.

Liquefied natural gas (LNG) leaks often lead to cascading accident disasters, including vapor cloud release, explosion, fire, and toxic gas release. The origin and evolution of each accidental disaster must be considered when assessing safety. This paper discusses the safety assessment project of an LNG gas storage station in Xuzhou, China. Multiple conceivable disasters due to the leakage of LNG storage tanks are simulated and analyzed using the computational fluid dynamic software FLACS. We studied different wind speeds interacting with the flammable vapor cloud area and creating frostbite in areas of low temperature. Diffusion simulations of vapor cloud explosion (VCE), thermal radiation, and the distribution of toxic substances were performed. The overpressure-impulse criterion was used to calculate the influence range of VCE. Heat flux, heat dose, and heat flux-heat dose criteria were used to calculate the safe distance for personnel in the event of fire. Based on the calculation results of the three latter criteria, this paper recommends using the heat flux criterion to evaluate fire accidents. The danger zone of each accident was compared. VCE accidents yielded the largest area.

To provide information concerning quantitative risk analysis of gas-storage caverns, it is vital to estimate the hazard area of dispersion caused by accidental leakage. The Gaussian plume model is selected to calculate the hazard area caused by continuous leakage; the method of analysis is validated using wind-tunnel experiments of acetylene. Fluent is used to simulate the hazard area of dispersion caused by instantaneous leakage; the method of numerical simulation is verified by Burro/Coyote trials. Furthermore, a sample underground gas-storage cavern in salt rock is examined with respect to the toxic threshold limit value and the upper and lower flammability limits. In doing so, the factors that influence the hazard range of dispersion from salt cavern are discussed. The results indicate that the hazard area decreases with an increase in wind speed and a decrease in atmospheric stability when the leakage is continuous. However, the hazard area decreases with a decrease in wind speed when leakage is instantaneous.

Background/Aims: This study aimed to report the clinical efficacy of continuous renal replacement therapy (CRRT) in combination with ultrasound-guided percutaneous transhepatic gallbladder drainage (PTGD) (CRRT+PTGD) in the treatment of acute severe biliary pancreatitis (ASBP). Methods: Between January 2010 and January 2016, 40 cases of patients with ASBP who received routine CRRT (CRRT group) and 40 of those who received CRRT+PTGD (CRRT+PTGD group) at the Affiliated Hospital of Qingdao University (Qingdao, China) were retrospectively reviewed. Clinical (including abdominal pain remission time, gastrointestinal decompression time, Intensive Care Unit (ICU) hospital stay, respirator treatment time, and mortality rate), laboratory (white blood cells [WBC], platelet [PLT], procalcitonin [PCT], C-reactive protein [CRP], total bilirubin [TBIL], alanine aminotransferase [ALT], albumin [ALB], and blood lactic acid [Lac]) parameters, various critical disease scores, and incidence of complications after the treatment were compared between the two groups. Results: Compared with those in the routine CRRT group, patients in the CRRT+PTGD group exhibited significant remission of clinical symptoms (i.e. shorter abdominal pain remission time, gastrointestinal decompression time, respirator treatment time and ICU hospital stay) (all P