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Abstract Purpose To investigate the changes in retinal vascular structures associated with various stages of myopia by designing automated software based on an artificial intelligence model. Methods The study involved 1324 pediatric participants from the National Children’s Medical Center in China, and 2366 high-quality retinal images and corresponding refractive parameters were obtained and analyzed. Spherical equivalent refraction (SER) degree was calculated. We proposed a data analysis model based on a combination of the Convolutional Neural Networks (CNN) model and the attention module to classify images, segment vascular structures, and measure vascular parameters, such as main angle (MA), branching angle (BA), bifurcation edge angle (BEA) and bifurcation edge coefficient (BEC). One-way ANOVA compared parameter measurements between the normal fundus, low myopia, moderate myopia, and high myopia groups. Results The mean age was 9.85 ± 2.60 years, with an average SER of -1.49 ± 3.16D in the right eye and − 1.48 ± 3.13D in the left eye. There were 279 (12.38%) images in the normal group and 384 (16.23%) images in the high myopia group. Compared with normal fundus, the MA of fundus vessels in different myopic refractive groups was significantly reduced (P = 0.006, P = 0.004, P = 0.019, respectively), and the performance of the venous system was particularly obvious (P

Abstract This paper describes the synthesis of a novel Cu–Ni bimetallic system comprising of magnetic nanoparticles, as the core, and 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole (4-ABPT), as a conjugated bridge, between nickel and copper species. With low Cu and Ni loading (0.06 mol% Ni, 0.08 mol% Cu), the resulting Fe3O4@SiO2@4-ABPT/Cu–Ni showed to be a highly efficient catalyst for the Sonogashira and C–N cross-coupling reactions. The developed catalyst was well characterized by FT-IR, XRD, EDX-mapping, FE-SEM, TEM, ICP, VSM, TGA/DTG/DTA, LSV, and XPS techniques. Fe3O4@SiO2@4-ABPT/Cu–Ni nanocatalyst was compatible with a wide range of amines and aryl halides in the Sonogashira and C–N cross-coupling reactions and offered desired coupling products in high to excellent yields under palladium- and solvent-free conditions. Based on the XPS results, the 4-ABPT ligand can adjust electron transfer between Ni and Cu in Fe3O4@SiO2@4-ABPT/Cu–Ni, promoting the formation and stabilization of Cu+ and Ni3+ species. Electronic interactions and the synergistic effect between these metals increased the selectivity and activity of Fe3O4@SiO2@4-ABPT/Cu–Ni catalyst in the Sonogashira and C–N cross-coupling reactions compared with its monometallic counterparts. Additionally, the magnetic properties of Fe3O4@SiO2@4-ABPT/Cu–Ni facilitated its separation from the reaction mixture, promoting its reuse for several times with no significant loss in its catalytic activity or performance.

Abstract A nanomagnetic hydrophilic heterogeneous copper catalyst, termed γ-Fe2O3@PEG@PAMAM G0-Cu, has been successfully prepared and characterized using FT–IR, XRD, FE-SEM, TEM, EDX, mapping, TGA/DTG, VSM and ICP analyses. The catalyst displayed excellent activity for the palladium-free Sonogashira cross coupling reaction of various aryl iodides and bromides with phenylacetylene derivatives in pure water. The presence of polyethylene glycol coupled with hydrophilic character of the Cu-catalyst adorned on γ-Fe2O3 MNPs provides the ready dispersion of the catalyst particles in water, leading to higher catalytic performance as well as facile catalyst recovery via simple magnetic decantation. The recovered catalyst was reused for at least six successive runs with little reduction in its catalytic activity and any noticeable changes in its structure. The use of water as a green solvent, without requiring any additive or organic solvent, as well as the exploitation of abundant and low-cost copper catalyst instead of expensive Pd catalyst along with the catalyst recovery and scalability, make this method favorable from environmental and economic points of view for the Sonogashira coupling reaction.

This study aimed to compare the efficacy of robot-assisted and manual cannula insertion in simulated big-bubble deep anterior lamellar keratoplasty (DALK). Novice surgeons with no prior experience in performing DALK were trained to perform the procedure using manual or robot-assisted techniques. The results showed that both methods could generate an airtight tunnel in the porcine cornea, and result in successful generation of a deep stromal demarcation plane representing sufficient depth reached for big-bubble generation in most cases. However, the combination of intraoperative OCT and robotic assistance received a significant increase in the depth of achieved detachment in non-perforated cases, comprising a mean of 89% as opposed to 85% of the cornea in manual trials. This research suggests that robot-assisted DALK may offer certain advantages over manual techniques, particularly when used in conjunction with intraoperative OCT.

In this work we demonstrate how to automate parts of the infectious disease-control policy-making process via performing inference in existing epidemiological models. The kind of inference tasks undertaken include computing the posterior distribution over controllable, via direct policy-making choices, simulation model parameters that give rise to acceptable disease progression outcomes. Among other things, we illustrate the use of a probabilistic programming language that automates inference in existing simulators. Neither the full capabilities of this tool for automating inference nor its utility for planning is widely disseminated at the current time. Timely gains in understanding about how such simulation-based models and inference automation tools applied in support of policy-making could lead to less economically damaging policy prescriptions, particularly during the current COVID-19 pandemic.

Antibiotics are organic pollutants that are introduced into surface water and underground water sources due to urban and industrial effluents. Due to their high stability, they do not only disrupt the common processes of sewage treatment, but also have toxic effects on humans and other living organisms, and their removal have therefore been considered. This is an experimental study in a laboratory scale with the aim of evaluating the efficiency of the new FeNi3/SiO2/CuS magnetic nanocomposite for the decomposition of metronidazole in the presence of H2O2 as a heterogeneous Fenton- like catalytic process in aqueous solutions. In present study, firstly, this nanocomposite was synthesized and characterized by FESEM, TEM, FTIR, XRD and VSM. This study, which was performed on synthetic sewage in batch system, parameters such as pH (3, 5, 7, 9 and 11), nanocomposite dose (0.005- 0.1 g/L), metronidazole concentration (10-30 mg/L) and the concentration of hydrogen peroxide (50-200 mg/L) at ambient temperature was investigated. The obtained results showed that the highest percentage of removal of metronidazole in pH =7, nanocomposite dose (0.1 g/L), hydrogen peroxide concentration of 150 mg/L for 20 mg/L contaminant concentration at time of 180 minutes, 77.92%. Also, the kinetic rate of degradation flowed pseudo-first-order equation (R2=0.95) and the degradation constant rate of this reaction is 0/0038 (1/min). Based on the results obtained from this study, it can be concluded that Hentrogenase Fenton like catalytic process has a very good effect in removing metronidazole antibiotic contamination from aqueous solutions.

Abstract Background In this research, different active phytochemical constituents present in Cleome heratensis (C. heratensis) from Capparaceae family were investigated. Moreover, the fatty acids present in the seed and aerial parts of the plant were identified by gas chromatography (GC) after esterification of the oil. Antioxidant activity of the aerial parts and seed of C. heratensis methanolic extract over 2,2′-diphenylpicryl-1-hydrazyl (DPPH) was investigated using ultraviolet–visible (UV–Vis) spectrophotometer. Methods To study total phenolic compounds and flavonoids, the plant was extracted from ethanol by ultrasonic method, then further extracted with other solvents. Amounts of anthocyanins and tannins/condensed tannins were determined by their corresponding ethanolic and acetone extracts. Antioxidant activity of the plant species was studied by a spectrophotometric method using 80% methanolic extract. Results The high content of phenolics as 16.915 mg tannic acid equivalents per gram of dry matter (TAE/g DM), tannins (12.231 mg TA/gr DM) and condensed tannins (4.086 mg TA/g DM) was obtained for the C. heratensis extract. The most flavonoids content was found 4.444 rutin equivalents (in mg) per gram of dry matter (mg RE/g DM) in plant’s aerial extract. The most amount of anthocyanin (0.48 mmol/gr WM) was observed in flowering stage. Antioxidant activity of the aerial parts and seed of C. heratensis methanolic extract were 11.92 and 63.54 mg/mL IC50, respectively. Conclusion High level of phenolic components including flavonoids, proanthocyanidins and tannins was detected in the extract of aerial parts of the plant. The oil of seed of this plant is a rich source of saturated and unsaturated fatty acids. Finally, C. heratensis aerial part extract was found as an excellent natural antioxidant.

In this present study, an environmentally friendly and rapid method for the synthesis of silver nanoparticles (SNPs) has been reported using Ziziphus Vulgaris (ZV) unripe fruit extract under mild conditions. The synthesized silver nanoparticles have been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible spectroscopy (UV–vis). Transmission electron microscopy analysis confirmed that the synthesized SNPs have spherical shape and their average size is about 20 nm. Moreover, antioxidant activity, total phenolic and flavonoid content of unripe fruit and seed were analyzed by DPPH free radical-scavenging, Folin Ciocalteu and aluminum chloride (AlCl3) assays, respectively. Different extracts of unripe fruit showed higher antioxidant activity, total phenol and flavonoid than seed of Ziziphus vulgaris. Moreover, antioxidant activity, total phenolic and flavonoid content of unripe fruit and seed were analyzed by DPPH free radical-scavenging, Folin Ciocalteu and aluminum chloride (AlCl3) assays, respectively. Different extracts of unripe fruit showed higher antioxidant activity, total phenol and flavonoid than seed of Ziziphus vulgaris.