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Abstract To achieve high-efficiency combustion of heavy fuel oil (HFO), this study investigated the combustion characteristics of methanol/HFO droplets with methanol content from 10 to 30% using the suspension method under ambient temperature from 923 to 1023 K. The combustion of methanol/HFO droplets was summarized as a two-phase process consisting of six typical stages, emphasizing liquid phase. Especially, the fluctuation evaporation stage, induced by frequent and intense puffing, was identified as prominent character. Both the ignition delay and lifetime of HFO and methanol/HFO droplets decreased with increasing ambient temperatures. For the methanol/HFO droplet, the ignition delay and droplet lifetime increased with the increasing methanol content. Prominently, compared to HFO, HM10 had the most significant reduction in droplet lifetime and TINL under the same operating conditions, which indicated that the addition of 10% methanol accelerated the combustion process and reduced soot generation. Additionally, the thermos-dynamic characteristics of methanol/HFO droplets were investigated. Puffing was primarily attributed to superheating of methanol and pyrolysis of heavy components in HFO, which resulted in active and passive rupture of bubbles. Similarity and maximum deformation were employed to qualitatively distinguish between them. The obtained findings aimed to develop a promising alternative fuel to reduce emissions and preserve energy.

Abstract Purpose To use artificial intelligence to establish an automatic diagnosis system for corneal endothelium diseases (CEDs). Methods We develop an automatic system for detecting multiple common CEDs involving an enhanced compact convolutional transformer (ECCT). Specifically, we introduce a cross-head relative position encoding scheme into a standard self-attention module to capture contextual information among different regions and employ a token-attention feed-forward network to place greater focus on valuable abnormal regions. Results A total of 2723 images from CED patients are used to train our system. It achieves an accuracy of 89.53%, and the area under the receiver operating characteristic curve (AUC) is 0.958 (95% CI 0.943–0.971) on images from multiple centres. Conclusions Our system is the first artificial intelligence-based system for diagnosing CEDs worldwide. Images can be uploaded to a specified website, and automatic diagnoses can be obtained; this system can be particularly helpful under pandemic conditions, such as those seen during the recent COVID-19 pandemic.

AIM: To compare the surgical outcomes of glaucoma drainage device implantation (GDI) and trans-scleral neodymium:YAG cyclophotocoagulation (CPC) in the management of refractory glaucoma after Descemet-stripping automated endothelial keratoplasty (DSAEK). METHODS: This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery (15 with GDI and 14 with CPC). The main outcome measures were intraocular pressure (IOP), glaucoma surgery success rate (defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation), number of glaucoma medications, endothelial graft status, and best-corrected visual acuity (BCVA). RESULTS: The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries, both for the GDI and CPC groups. Both groups showed significant IOP reduction after glaucoma surgery. The GDI group presented a significantly higher success rate in IOP control than the CPC group (60% vs 21.4%, P=0.03). Both procedures significantly decreased the number of glaucoma medications (P=0.03). Forty percent and 57% of cases in the GDI and the CPC group, respectively, experienced endothelial graft failure during follow-up (P=0.36). Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group. CONCLUSION: Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK. GDI is preferable to CPC in refractory glaucoma cases after DSAEK, as it manifests a significantly higher success rate for IOP control, similar endothelial graft failure rate, and relatively preserves BCVA than CPC.

Objectives To find out the prevalence rate of pre-myopia among primary school students in the Mianyang Science City Area, analyze its related risk factors, and thus provide a reference for local authorities to formulate policies on the prevention and control of myopia for primary school students. Methods October 2022, Cluster sampling was adopted by our research group to obtain the vision levels of 2278 primary school students employing a diopter test in the Science City Area. In addition, questionnaires were distributed to help us find the risk factors associated with pre-myopia. Results The prevalence rate of pre-myopia among primary school students in the Science City Area was 45.27%, of which 43.82% were boys and 46.92% were girls, with no statistically significant difference in the prevalence rate of myopia between boys and girls (c2 =2.171, P=0.141). Multiple logistic regression analysis demonstrated that the main risk factors for pre-myopia were having at least one parent with severe myopia, spending less than 2 hours a day outdoors, lack of sleep looking at electronic screens for more than 1 hours, and having an improper reading and writing posture. Outdoor activity time less than 2 hours per day, lack of sleep, looking at the electronic screen for more than 1 hour per day, and incorrect reading and writing posture were all positively associated with the pre-myopia (P values < 0.05). Conclusion The Science City Area has a high prevalence rate of pre-myopia among primary school students. It is proposed that students, schools, families, and local authorities work together to increase the time spent outdoors, get adequate sleep, reduce the time spent staring at digital screens and develop scientific use of eye habits.

Abstract Objective To explore the effect of the 2016 Chinese second child policy and different maternal ages on adverse perinatal outcomes. Methods Clinical data were collected from 22 monitoring hospitals in Hebei Province from January 1, 2013, to December 31, 2021. A total of 413,892 parturient were divided into 3 groups based on delivery age: 20–34, 35–39, and 40–55 years old. The clinical data were analyzed to explore the relationship among the 2016 Chinese second-child policy, maternal age, and various pregnancy risks. Results Pregnancy complications showed an upward trend from 2013 to 2021.The top 10 incidences of pregnancy complications in Hebei Province were anemia, small for gestational age (SGA), large for gestational age (LGA), macrosomia, gestational diabetes mellitus (GDM), premature delivery, preeclampsia (PE), postpartum hemorrhage (PPH), placenta previa, and placental abruption. The two-child policy was implemented in 2016. The incidence of pregnancy complications, anemia, GDM, PE, placental abruption, cesarean delivery, premature delivery, SGA, LGA, macrosomia in 2016–2021 was significantly higher than that in 2013–2015 (P

AIM: To investigate corneal graft survival rate and endothelial cell density (ECD) loss after keratoplasty in cytomegalovirus (CMV) positive patients. METHODS: This was a retrospective cohort study. We analyzed the clinical data of patients who underwent viral DNA detection in aqueous humor/corneal tissue collected during keratoplasty from March 2015 to December 2018 at the Peking University Third Hospital, Beijing, China. To further evaluate the effect of CMV on graft survival rate and ECD loss, patients were divided into three groups: 1) CMV DNA positive (CMV+) group; 2) viral DNA negative (virus-) group, comprising virus- group eyes pairwise matched to eyes in the CMV+ group according to ocular comorbidities; 3) control group, comprising virus- group eyes without ocular comorbidities. The follow-up indicators including graft survival rate, ECD, ECD loss, and central corneal thickness (CCT), were analyzed by Tukey honestly significant difference (HSD) test. RESULTS: Each group included 29 cases. The graft survival rate in CMV+ group were lowest among the three groups (P=0.000). No significant difference in donor graft ECD was found among three groups (P=0.54). ECD in the CMV+ group was lower than the virus- group at 12 (P=0.009), and 24mo (P=0.002) after keratoplasties. Furthermore, ECD loss was higher in the CMV+ group than in the virus- group in the middle stage (6-12mo) post-keratoplasty (P=0.017), and significantly higher in the early stage (0-6mo) in the virus- group than in the control group (P=0.000). CONCLUSION: CMV reduces the graft survival rate and exerts persistent detrimental effects on the ECD after keratoplasty. The graft ECD loss associate with CMV infection mainly occurrs in the middle stage (6-12mo postoperatively), while ocular comorbidities mainly affects ECD in the early stage (0-6mo postoperatively).

PurposeThe purpose of this study was to investigate the in vivo morphologic features of the cornea in patients with unilateral posterior interstitial keratitis.MethodsSeven eyes of 7 patients with unilateral posterior interstitial keratitis were examined by slit-lamp biomicroscopy, anterior segment optical coherence tomography (AS-OCT), and in vivo confocal microscopy (IVCM). The imaging features of the cornea were evaluated and analyzed.ResultsBy slit-lamp examination, the posterior corneal stromal opacities were observed in all 7 eyes, and deep neovascularization in 4 eyes. The posterior stromal opacities showed higher reflectivity with an intact overlying epithelium by AS-OCT and did not invade the Bowman’s layer in all cases. IVCM revealed highly reflective dispersed microdots, needle-shaped bodies, and increased reflectivity of keratocytes in the lesion site in all patients. Active Langerhans cells and an attenuated subbasal nerve plexus were observed in 5 eyes. After treatment, the active Langerhans cells disappeared; however, highly reflective microdots and needle-shaped bodies remained.ConclusionThe three-dimensional evaluation of slit-lamp biomicroscopy, AS-OCT, and IVCM may help in the early diagnosis of patients with posterior interstitial keratitis.

To develop a highly selective extractant for Pu(Ⅳ), 2,2′-((4-ethoxy-1,2-phenylene)bis(oxy)) bis (N,N-bis(2-ethylhexyl)acetamide), short for 4-EthoxyBenzoDODA, has been evaluated as a novel extractant in n-dodecane diluent for the extraction of U(Ⅵ) and Pu(Ⅳ). The effect of contact time of two phases, HNO3 concentration and extractant concentration on the distribution ratios of U(Ⅵ) and Pu(Ⅳ) was investigated. Acid uptake studies suggested that 4-EthoxyBenzoDODA (KH=0.14) was less basic as compared to BenzoDODA (KH=0.44), making it more conducive to selectively extract Pu(Ⅳ) with stronger ionic potential. Extraction experiments showed that the maximum of SFPu/U, SFPu/Eu were 6.9, 223 respectively. Slope analysis indicated extraction of 1∶1 (ML) species with U(Ⅵ) and mixed 1∶1 (ML) and 1∶2 (ML2) species with Pu(Ⅳ) at 4.0 mol/L HNO3 98% of Pu in the loaded organic phase can be stripped to the aqueous phase using reductive stripping agent such as hydrazine nitrate and hydroxylamine nitrate. The results showed that the 4-EthoxyBenzoDODA exhibited good selectivity toward Pu.