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This study demonstrates the applicability of microscale zero-valent iron (mZVI) in the removal of C.I. Vat Green 1 dye from water by adsorption. mZVI particles were characterized by SEM, EDX, BET surface area analysis and pHzpc. The changes in the surface properties of the mZVI particles used in the analysis were determined by SEM and EDX. Spherical particles smaller than about 5 µm with a surface area of 5.2 m²/g BET supported the high removal efficiency. Changes in particle size and shape and elemental composition after the analysis confirmed the high adsorption efficiency, and the pHzpc value of 5.73 led to high removal efficiency at low pH. In order to evaluate the removal efficiency, adsorption kinetics and isotherms of C.I. Vat Green 1, parameters such as solution pH, iron dosage, reaction temperature and pollutant concentration were investigated by batch series of experiments. While the removal efficiency decreased at pH values greater than 3, mZVI dosages greater than 1 g/L and increased pollutant concentration, the efficiency increased at dosages up to 1 g/L and with temperature increase. It was determined that the optimum pH was 3 and the optimum mZVI dosage was 1 g/L. The results of TOC analysis also confirmed that the removal mechanism is adsorption. It was found that the kinetic data fit the pseudo second order model best. The adsorption equilibrium data were represented by the Langmuir model and the maximum adsorption capacity was found to be 36.50 mg/g. [ABSTRACT FROM AUTHOR]

A microscale Fe/Ni bimetallic particle was examined to convert O2 to H2O2 and further to •OH radicals and to degrade metronidazole (MNZ) antibiotic in a heterogeneous Fenton-like reaction. The properties of the bimetallic particle before and after the reaction were studied using SEM, EDX, XRD, and BET techniques. The complete removal of MNZ was achieved within 15 min with an initial pH of 3, oxygen flow rate of 150 L/h, Fe/Ni of 1 g/L, and MNZ of 25 mg/L. Under these conditions, the maximum H2O2 concentration of about 31 mg/L was generated but only 27% of TOC was removed after 60 min. The presence of NaCl and the high ionic strength accelerated the iron dissolution and MNZ removal efficiency. The reaction was mainly inhibited at the solution pH of 7, implying the significance of solution pH in Fenton-like process. Besides, the possible MNZ degradation pathway was further proposed based on the intermediates identified by GC/MS. Acetamide was monitored as the degradation intermediate. The results showed a significant contribution on the usage of a catalyst for in-situ generation of H2O2 via the activation of dissolved oxygen. [ABSTRACT FROM AUTHOR]

The removal of paracetamol pharmaceutical from the aqueous solution by activated carbon prepared from wood sawdust (WSAC) was studied in the current research. The Response Surface Methodology (RSM) was used to model WSAC paracetamol removal, optimize operational parameters, and determine the impact of operational parameters such as adsorbent dosage, initial concentration of paracetamol, and contact time. According to the results of variance analysis (ANOVA), the quadratic model was statistically significant (P < 0.0001), and the determination coefficient value (R2=0.9847) was high. The high determination coefficient value of the quadratic model indicated that the experimental results adapted well with the predicted results, that is, the model was valid for envisaging the experimental results. The optimum conditions were obtained to be 0.16 g/100 mL WSAC dosage, 11.52 mg/L initial paracetamol concentration, and 90.52 min contact time by the desirability function, resulting in the paracetamol removal of 99.24%. The results of the isotherm studies indicated that the isotherm equations of Langmuir, Temkin, and Dubinin all fit the paracetamol adsorption data. The maximum adsorption capacity (qmax) of WSAC was calculated as 15.90 mg/g using the Langmuir isotherm equation. Kinetic study results revealed that the pseudo-second-order kinetic model adapted well to the paracetamol adsorption data. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effective optical zones (EOZs) of small-incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (F-LASIK) by utilizing topographic methods on the tangential curvature difference map at postoperative 1 year and to identify parameters linked to the EOZ alterations following both surgeries. Methods: Myopic patients who underwent SMILE or F-LASIK were included in the study. Patients with refractive error greater than −9.0 D sphere or −0.50 D of astigmatism were excluded from the study. EOZs were measured at postoperative 1 year by using the tangential curvature difference map of the Scheimpflug tomography system. Correlations between the EOZ alterations and relevant parameters were assessed. Results: In total, 59 eyes in the SMILE group and 65 eyes in the F-LASIK group were assessed. The decrease in EOZ compared with the programmed optical zone was significantly higher in the F-LASIK group (P < 0.001). The increase in corneal asphericity was significantly relevant to the decrease in EOZin both groups according to the multiple regression analysis (P < 0.001, B/95% CI: 0.62/0.34 and 0.90, standardized-Beta: 0.587 for the SMILE group; P < 0.001, B/95% CI: 0.74/0.41 and 1.07, standardized-Beta: 0.631 for the F-LASIK group). Conclusion: The EOZ decreased 1 year after both SMILE and F-LASIK. The SMILE group showed less EOZ reduction than F-LASIK patients relative to the programmed optical zone. The decrease in EOZ was correlated with the increase in corneal asphericity in both groups. [ABSTRACT FROM AUTHOR]

Objectives To assess the appropriateness and readability of large language model (LLM) chatbots' answers to frequently asked questions about refractive surgery. Materials and Methods Four commonly used LLM chatbots were asked 40 questions frequently asked by patients about refractive surgery. The appropriateness of the answers was evaluated by 2 experienced refractive surgeons. Readability was evaluated with 5 different indexes. Results Based on the responses generated by the LLM chatbots, 45% (n=18) of the answers given by ChatGPT 3.5 were correct, while this rate was 52.5% (n=21) for ChatGPT 4.0, 87.5% (n=35) for Gemini, and 60% (n=24) for Copilot. In terms of readability, it was observed that all LLM chatbots were very difficult to read and required a university degree. Conclusion These LLM chatbots, which are finding a place in our daily lives, can occasionally provide inappropriate answers. Although all were difficult to read, Gemini was the most successful LLM chatbot in terms of generating appropriate answers and was relatively better in terms of readability. Keywords:Artificial intelligence, chatbots, refractive surgery FAQs, ChatGPT, Gemini, Copilot: [ABSTRACT FROM AUTHOR]

In this study, the performance of chitin for removing chlortetracycline (CTC) from aqueous solutions was assessed. The effects of pH, chitin dose, CTC concentration and contact time on CTC adsorption by chitin were investigated. The maximum CTC removal efficiency of 82.9% was determined at pH 7, chitin dose of 5 g/L, CTC concentration of 8.8 mg/L and contact time of 120 min. The highest CTC adsorption capacity was found as 12.01 mg/g for CTC of 82.2 mg/L concentration at pH 7. The results demonstrated that CTC removal efficiency decreased from 82.9% to 73.0% with increasing CTC concentration from 8.8 to 82.2 mg/L. The equilibrium data for CTC adsorption indicated a good fit to the Freundlich isotherm model. Pseudo-second-order kinetic model was the best model for describing the adsorption reactions. [ABSTRACT FROM AUTHOR]

Turkey has one of the largest lignite deposits in Europe but the low calorific values of Turkish lignites dictate new and environmentally safe new utilization technologies for further utilization. Research on coal chemical structures has long been of great interest as a fundamental issue for coal chemistry. Identifying the structures of organic material in lignites is important for lignite conversions to clean liquid fuels and value-added chemicals. Therefore, investigation of chemical and degree of ordered structure present in Turkish lignites is desirable. We report structural information of two coals from the Manisa Soma region, two from the Mugla Yatagan region and one from Kutahya Seyitomer region. FTIR spectra of coal samples contained peaks due to OH and C O functional groups, aliphatic CH, CH 2 , CH 3 and aromatic C C and aromatic-CH structures. Coals with higher fixed carbon were oxidized more after oxidation experiments, as evidenced by the higher intensity of the C O band. Coals that contained higher amounts of nonpolar alkyl and aromatic C C, C-H groups were affected more by the oxidation reactions, which formed high-intensity C O band. XRD investigation revealed crystal structures present in the lignites were arranged slightly to form turbostratic arrangement. The structure of Yatagan region coals was less ordered compared to the other samples. The XRD aromaticity ( f a ) of the coals ranged between 0.642 and 0.777. Investigations showed that there was a good correlation between calculated structural parameters and maturity of the coals. Raman spectra of the coals revealed that samples contained significant proportions of highly disordered amorphous carbon structures. 13 C NMR aromaticities of the coal samples were found between 0.536 and 0.754. Aromaticity values obtained by XRD and NMR methods were in high correlation. [ABSTRACT FROM AUTHOR]

Purpose: To compare the visual acuity, topographic and the biomicroscopic features in patients who had accelerated corneal crosslinking (CXL) by using hydroxypropyl methylcellulose-based (HPMC) or dextran-based riboflavin solutions. Materials and Methods: In this study, 62 eyes with progressive keratoconus were included. Accelerated CXL has been performed to all patients. Riboflavin with dextran (0.1% Riboflavin, 20% dextran) (n: 33) or HPMC (0.1% Riboflavin, 1.1% HPMC) (n: 29) were used as photosensitizer in CXL procedure. Visual acuity, topographic measurements and biomicroscopic features were compared between 2 groups in 12 months of follow-up. Results: Totally 62 eyes (34 right and 28 left) of 62 patients (25 female, 37 male) with a mean age of 24.37±6.93 years were included. Although best corrected visual acuity (0.29 ±0.16 vs 0.28±0.16; p= 0.89) and uncorrected visual acuity (0.62 ±0.34 vs 0.48±0.29; p=0.08) were both better in dextran free riboflavin group at 12th month of follow-up, the differences between 2 groups were not statistically significant. There was not any statistically significant difference between groups regarding any of the topographic findings. The biomicroscopic findings were also very similar in first, sixth and 12th months of follow-up in both groups. Corneal haze was the most common finding in the 1st month of follow up in all cases. Conclusions: Accelerated CXL procedures performed by using riboflavin with dextran or HPMC represent similar affects in corneal parameters during the 12 months of follow-up period. Larger studies with longer follow-up periods are warranted to define the differences and similarities of these 2 photosensitizers. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the prognostic factors affecting graft survival in patients undergoing penetrating keratoplasty (PKP) for infectious keratitis. Materials and methods: Patients who underwent PKP for keratitis in our hospital between 2013 and 2018 were retrospectively reviewed. Patients who underwent therapeutic PKP at the inflammatory stage and were followed for at least 12 months were included in the study. Age, gender, follow-up period, time between diagnosis and surgery, lens status, presence of limbal involvement, presence of corneal ulceration, perforation, or corneal abscess, type of microorganism detected in culture, number of fortified medications used before surgery and duration of use, preoperative and postoperative visual acuity, postoperative graft transparency, postoperative complications, recurrence of infection, rate of re-keratoplasty, and indication for and timing of re-keratoplasty were recorded. The relationship between these findings and anatomic, therapeutic, and functional success were evaluated. Results: Fifty-nine patients were included in the study; 40 (67.8%) were male and 19 (32.2%) were female, and the mean age was 59.78±19.46 (6-91) years. Anatomic success was achieved in 58 patients (98.3%). Therapeutic success was achieved in 47 patients (79.7%) and there was a significant relationship between therapeutic success and re-keratoplasty and early re-keratoplasty (p<0.001 for both). Thirty-two patients (54.2%) had functional success and there was a significant relationship between the absence of postoperative complications and functional success (p=0.014). Conclusion: PKP is an effective treatment option in treatment-resistant keratitis or keratitis with impending perforation. The absence of postoperative complications and performing early re-keratoplasty in patients with recurrence increase the success rate. [ABSTRACT FROM AUTHOR]

Purpose To report long-term efficacy and safety of small-incision lenticule extraction (SMILE) in patients with mild-to-moderate myopia. Setting Beyoglu Eye Training and Research Hospital, İstanbul, Turkey. Design Retrospective case series. Methods Medical records of patients who had SMILE for surgical correction of myopia or myopic astigmatism were retrospectively reviewed. Patients with a preoperative spherical equivalent (SE) of manifest refraction of 6.00 D or less and a 5-year follow-up period were included in the study. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities and SE were analyzed preoperatively and at 1 year, 3 years, and 5 years postoperatively. Results The study comprised 54 eyes (34 patients). The mean SE of the intended correction was −4.11 diopters (D) ± 0.98 (SD) and ranged from −1.38 to −5.88 D. The mean preoperative UDVA and CDVA were 1.08 ± 0.29 logarithm of the minimum angle of resolution (logMAR) and 0.02 ± 0.08 logMAR, respectively. At the 5-year follow-up, the mean difference between the intended and achieved SE was −0.13 ± 0.29 D. The mean postoperative UDVA and CDVA were 0.04 ± 0.09 logMAR and 0.00 ± 0.04 logMAR, respectively. At the 5-year follow-up, the SE was within ±0.50 D of the intended correction in 32 (93%) of the 34 patients and within ±1.00 D of intended correction in all patients. The SE at the 5-year follow-up was within ±0.50 D of the 1-year visit in 33 (98%) of all patients. No patient lost CDVA lines, and no vision-threatening events occurred during the surgery or the postoperative period. Conclusions SMILE in mild-to-moderate myopia offers predictable correction of SE refractive error. Refractive results were stable at the long-term follow-up. [ABSTRACT FROM AUTHOR]

Objective: This study aims to evaluate the effect of intended correction on early visual acuity after small-incision lenticule extraction (SMILE). Methods: Medical records of patients who underwent SMILE for surgical correction of myopia were retrospectively reviewed. Patients with preoperative visual acuity =1.0 and spherical equivalent (SE) of manifest refractive error within =±025 D of emmetropia at 1 month were included in the study. The group with low myopia (Group 1, SE <3 D) was compared to the group with moderate to high myopia (Group 2, SE >3 D). The main outcome measure was the corrected distance visual acuity (CDVA) at 1-day, 1-week, and 1-month visits. Results: The mean attempted SE was -2.49±0.35 D and -4.65±1.29 D in Groups 1 and 2, respectively. There was no statistically significant correlation between the intended correction and CDVA at 1 day, 1 week, or 1 month. At 1 day postoperation, 33% and 8% of eyes in Groups 1 and 2 lost two or more lines of CDVA, respectively (p=0.026). No patients lost two or more lines at 1 month. Conclusion: The loss of two or more lines of CDVA after SMILE in the early postoperative period was more common among patients who had low myopia preoperatively. CDVA improved during the first month after SMILE. [ABSTRACT FROM AUTHOR]

Purpose. To report long-term visual and refractive results of small-incision lenticule extraction (SMILE) in treatment of high myopia. Materials and Methods. Medical records of patients who underwent SMILE for surgical correction of myopia or myopic astigmatism were retrospectively reviewed. Only patients with a preoperative spherical equivalent of subjective manifest refraction (SE) ≥ 6 D and a postoperative follow-up of 5 years were included in the study. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and SE were analyzed preoperatively and at 1-, 3-, and 5-year postoperative periods. Results. Thirty-seven eyes of 37 patients were included in the study. The mean attempted SE was −7.47 ± 1.10 D (range −6.00 to −10.00 D). At the 5-year visit, the mean difference between achieved and attempted SE was −0.43 ± 0.47 (0.50 to −1.25 D). Mean postoperative UDVA and CDVA were 0.20 ± 0.18 and 0.06 ± 0.08 logMAR, respectively. At the 1-year visit, 70% and 97% of the eyes were within ±0.50 D and ±1.00 D of the intended correction. At the 5-year follow-up, 59% and 92% percent of the eyes were within ±0.50 D and ±1.00 D of the intended SE, respectively. At the 5-year visit, the efficacy index was 0.89 ± 0.26 and the safety index was 1.16 ± 0.20. Fifty-four percent of the eyes gained one or more lines of CDVA. Conclusion. SMILE with an intended correction of up to a spherical equivalent of 10 D is safe and effective. However, there is regression of the refractive effect over extended follow-up. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the visual, refractive, and topographic outcomes after simultaneous topography-guided transepithelial photorefractive keratectomy (transepithelial TG-PRK) using the Amaris Excimer laser platform and accelerated corneal cross-linking (CXL) in eyes with keratoconus. Materials and Methods. Patients with 2 years of follow-up were included in this retrospective case series. Manifest refraction (MR), uncorrected (UDVA) and corrected (CDVA) distance visual acuity, corneal topography, and pachymetry were evaluated at 1, 3, 6, 12, and 24 months after surgery. The root-mean-square of total higher-order aberrations (total HOA-RMS), coma (Coma-RMS), and spherical aberration (SA-RMS) were calculated for 4- and 6-mm diameters. Results. Forty-six eyes of 46 patients were included in the study. Stromal ablation was ≤50 μ in all patients. MR was −3.78±3.26 preoperatively and −1.39±1.82 postoperatively. Significant improvements were seen in the UDVA and Coma-RMS values at 1 month, CDVA and total HOA-RMS values at 3 months, and SA-RMS values at 1 year compared to preoperative levels. UDVA values further improved after 2 years, compared to the 1-year values. No patient lost two or more lines and keratoconus progression was not observed in any patient. Conclusion. Simultaneous transepithelial TG-PRK and accelerated CXL resulted in significant gains in CDVA without compromising CXL efficacy. [ABSTRACT FROM AUTHOR]

To investigate the corneal bacterial microbiome in patients with keratoconus using next-generation sequencing and develop a new perspective on the pathogenesis of the disease. This prospective observational study included 10 patients with keratoconus who underwent corneal crosslinking procedure and 10 healthy controls who underwent photorefractive keratectomy. Patients included in the study were aged 18 years or older. The demographic and clinical characteristics of participants were recorded. Corneal epithelial samples were collected between March 2021 and June 2021. Isolated bacterial DNA from corneal epithelial samples was analyzed using 16 S ribosomal RNA gene analysis. The relative abundance rates at the phylum and genus levels were calculated. Alpha diversity parameters were assessed. Eleven phyla and 521 genera of bacteria were identified in all participants. At the phylum level, Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes were most abundant in both groups. There were no statistical differences between the two groups except Bacteriodetes (p < 0.05). At the genus level, the relative abundance rates of twenty bacteria were significantly different between keratoconus and healthy corneas (p < 0.05). Aquabacterium was the most abundant genus in patients with keratoconus, while Shigella was the most abundant genus in healthy controls. Alpha diversity parameters were lower in patients with keratoconus, although the difference did not reach statistical significance (p > 0.05). Our preliminary study revealed that there are similarities and differences in the corneal microbiome between keratoconus and healthy individuals. Further research is required on the relationship between the abnormal corneal microbiome composition and the pathogenesis of keratoconus. • The presence of 11 phyla and 521 genera of bacteria was identified in the corneal microbiome of all participants. • The most abundant phyla were Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes, respectively. • Aquabacterium, Staphlococcus, and Paraburkholderia were present in all corneal samples. • The relative abundance rates of 20 genera were significantly different between keratoconus and healthy corneas. • Our preliminary study suggested that the corneal microbiome in keratoconus is distinct from healthy corneas. [ABSTRACT FROM AUTHOR]

The effects of the ischemia and reperfusion on the lens metabolites and the effect of a phytotherapeutic commercial product called "Enoant" (mixed polyphenol content) on the selected lens metabolites were investigated. For this aim, 30Wistar rats were divided into three groups according to their diet and being subjected to ischemia. 10 of the rats as Group I were fed on dry diet; the other 10 (Group II) were fed on dry diet and drinking water with Enoant. At the end of 15 days period, both groups of rats were subjected to ischemia for 2 hours and reperfused. After another 15 days with their same diet, the rats were decapitated.The remaining 10 rats, whichwere not subjected to ischemia (Group III),were fed on dry diet only. 1HNMR spectroscopy was used for the determination of lens metabolites of each group of rats.The results obtained fromthe three groups have been compared statistically.Thedifferences of metabolites were significant except pyruvate and succinate.Oral administration of Enoant revealed effects on increasing membrane stabilization, the antioxidant capacity, osmotic regulator molecule capacity, and sorbitol content of lens disturbed by ischemia. Enoant can be used where oxidative or osmotic stress is formed. [ABSTRACT FROM AUTHOR]