Abstract (Introduction): The search for techniques and methods for managing sludge generated during wastewater treatment is necessary to ensure sustainable sanitation in the medium term in Latin America. An interesting approach involves converting sludge into a biosolid usable in agriculture through alkaline sanitization. (Objective): We evaluated this technique’s efficacy and economic and environmental viability for obtaining an agriculturally usable type A biosolid from municipal wastewater treatment plant (WWTP) sludge. (Methodology): To this end, the efficacy in reducing microbiological parameters was experimentally tested at the laboratory scale using quicklime, for anaerobic and aerobic WWTP sludge. The experimental results fed a benefit/cost analysis model and a life cycle assessment. (Results): It was confirmed that applying a 40 % lime dose allowed the obtention of a type A biosolid with non-detectable concentrations of pathogenic microorganisms, which remained in that condition for more than 30 days. Additionally, the benefit/cost and life cycle analyses concluded that this option would be more attractive than sludge disposal in a landfill, due to the corresponding savings in chemical compounds (fertilizers, agricultural lime). (Conclusions): Therefore, alkaline sanitization can be considered suitable for WWTP sludge management. Its application on a larger scale should be further investigated in the country and the Latin-American region, considering the risk associated to the presence of heavy metals too.

Resumen (Introducción): La búsqueda de técnicas y modelos de gestión del lodo generado durante el tratamiento de las aguas residuales es necesaria para garantizar un saneamiento sostenible a mediano plazo en América Latina. Una vía interesante consiste en convertir el lodo en un biosólido aprovechable en la agricultura por medio de la higienización alcalina. (Objetivo): Se evaluó la eficacia y la viabilidad económica y ambiental de esta técnica para la obtención de un biosólido tipo A aprovechable en la agricultura a partir de lodo de planta de tratamiento de aguas residuales (PTAR) ordinaria. (Metodología): Para ello se probó experimentalmente en escala de laboratorio la eficacia en el decaimiento de parámetros microbiológicos higienizados con cal viva, usando lodo anaeróbico y aeróbico de PTAR. Los resultados experimentales alimentaron un modelo de análisis de beneficio/costo y de ciclo de vida. (Resultados): Pudo corroborarse que la aplicación de dosis de cal de 40 % permitió obtener un biosólido tipo A con concentraciones de microorganismos patógenos no detectables, lo cual se mantuvo en esa condición por más de 30 días. Además, el análisis de beneficio/costo y de ciclo de vida permitieron concluir que esta opción sería más atractiva que la disposición del lodo en un relleno sanitario, debido al ahorro correspondiente en compuestos químicos (fertilizantes o cal agrícola) derivado de su aprovechamiento. (Conclusiones): Por lo tanto, la técnica de higienización alcalina puede considerarse como adecuada para la gestión del lodo de PTAR y su aplicación a mayor escala debe investigarse en mayor detalle en el país y la región latinoamericana, considerando también el riesgo de presencia de metales pesados en este subproducto.

Abstract: Wood is an important structural material, but some undesirable properties limit its application in construction. This study investigated the effect of tin alloy thermal modification (TTM) on selected physical and mechanical properties of Firmiana simplex (Chinese bottletree) wood. Tin alloy thermal modification of F. simplex was performed in a tin alloy bath at two different temperatures (150 oC and 210 oC for 2 h and 8 h). Physical properties such as swelling, water absorption and density and mechanical properties like modulus of elasticity, modulus of rupture, impact bending, compression strength and Brinell hardness of tin alloy thermal modified and control samples were evaluated. The results showed that tin alloy thermal modification decreased the swelling of the wood to 4,85 %, 1,45 % and 6,99 % along the tangential, radial and volumetric coefficient and water absorption and density decreased to 53,10 % and 290 kg/m3 respectively compared to the control. Modulus of elasticity, modulus of rupture, impact bending, compression strength and Brinell hardness of tin alloy thermal modified F. simplex at 210 °C for 8 h decreased to 6366,1 MPa, 54,9 MPa, 2,7 MPa, 29,4 MPa and 1113,5 MPa respectively compared to the control. In conclusion, the tin alloy thermal modified wood at 210 oC significantly affected the physical and mechanical properties of the wood.

Abstract: The aim of this study was to evaluate the environment-performance relationship of surface coating applications on data obtained by measuring the emission rates of volatile organic compounds in polyurethane and water-based varnishes. For this purpose, polyurethane and water-based varnishes from five different companies were applied to the test samples of Entandrophragma cylindricum (sapele) and Piptadeniastrum africanum (dabema), both widely used in the production of urban furniture. Volatile organic compound, hardness and adhesion strength were measured during application. When evaluated in terms of performance, polyurethane varnishes showed superior hardness, while water-based varnishes demonstrated better adhesion after the UV test. The hardness values of polyurethane varnishes before and after the UV aging test were 15,9 s and 79,403 s, respectively, while forwater-based varnishes were , the values were 114,92 s and 75,406 s. The adhesion values of water-based varnishes were 2,885 MPa and 1,18 MPa before and after the UV aging test, and for polyurethane varnishes 3,13 MPa and 1,05 MPa for. When the environment-oriented results were evaluated, the ; emission values of volatile organic compounds in polyurethane varnish applications were found to be significantly higher than those in in water-based varnishes applications. While the total emission rate of volatile organic compounds detected in polyurethane varnishes was 53,63 mg/Nm3, while only one brand of water-based varnishes showed a measurable emission value, recorded at 0,0057 mg/Nm3. The volatile organic compounds emission values of other water-based varnishes were below the device detection limit (<0,0035 mg/Nm3), and therefore could not be measured.

The use of materials such as organofunctionalized silica for application in solid phase extraction (SPE) allows the preconcentration of several ions, including Pt, and subsequent detection. This work aims to synthesize and characterize an organofunctionalized silica (Sil-TMSDT) with the silylant N’(trimethoxysilyl)propylethylenetriamine and its application as a solid phase in the preconcentration Pt4+ ions in aqueous media, using detection by flame atomization atomic absorption spectroscopy (FAAS). The Fourier-transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) confirmed the aminofunctionalization of the silica. For the adsorption process, a preconcentration mini-column with 200 mg of Sil-TMSDT, a solution of 0.485 mg L−1 of K2[PtCl6] at pH 10 and HNO3 0.5 mol L−1 as eluent were used, obtaining an enrichment factor of 15-fold with retention efficiency higher than 99%. The Pt4+ ion determined by FAAS showed a linear response between 0.02 and 0.40 mg L−1; a linear coefficient where R = 0.9981; a 16-fold preconcentration factor; a limit of quantification (LOQ) and limit of detection (LOD) of 0.045 and 0.014 mg L−1, respectively. The proposal system showed analytical applicability to determining Pt4+ ion in an aqueous medium and could be used to detect traces of this potentially toxic metal in biological fluids such as urine and blood. SPE (SPE Pt SilTMSDT Sil TMSDT (Sil-TMSDT Ntrimethoxysilylpropylethylenetriamine N trimethoxysilyl propylethylenetriamine Pt4 media FAAS. . (FAAS) Fouriertransform Fourier transform FTIR (FTIR SEM (SEM energydispersive energy dispersive EDS (EDS process minicolumn mini column 20 SilTMSDT, TMSDT, Sil-TMSDT 0485 0 485 0.48 L1 L 1 L− K2PtCl6 KPtCl K2 PtCl6 K PtCl K2[PtCl6 HNO 05 5 0. 15fold fold 15 99 99% 002 02 0.0 040 40 0.4 0.9981 09981 9981 16fold 16 LOQ (LOQ LOD (LOD 0045 045 0.04 0014 014 0.01 respectively blood (FAAS 2 048 48 K2PtCl K2[PtCl 9 00 04 4 0.998 0998 998 004 001 01 0.99 099 0.9 09

Bisphenol A (BPA), an endocrine disruptor used in different commercial polymers, is a persistent pollutant commonly found in effluents. Conventional wastewater treatment processes have low chemical removal efficiency and are expensive. This work evaluated BPA removal using laccase enzyme produced from white rot fungus Pleurotus ostreatus. For the enzymatic production, residues of acai berry and pineapple were used as laccase inducers. The use of natural inducers led to a high enzyme production (1139 and 1031 U mL−1 to acai and pineapple, respectively). Bisphenol A was removed to a concentration lower than LOD (limit of detection) after 4 h. The degradation mechanism of BPA occurred by oxidation of methyl to hydroxymethyl group in a propane portion, with breakdown of the aromatic ring. The developed technology brought to the scene a new green, viable methodology, using vegetable waste, adding value to these residues and bringing an alternative to the BPA treatment. BPA, , (BPA) polymers effluents expensive ostreatus 1139 (113 103 mL1 mL 1 mL− respectively. respectively . respectively) limit detection h portion ring green methodology waste (BPA 113 (11 10 11 (1 (

EFFECT OF LIQUID SWINE WASTEWATER DOSES ON PHYSICAL, CHEMICAL AND ELECTROCHEMICAL ATTRIBUTES IN A CERRADO OXISOL. The addition of organic residues enhances soil and plant organic matter and nutrient content. To gauge the impact of varying liquid swine waste (LSW) levels on soil, we studied changes in a clayey Oxisol’s physical, chemical, and electrochemical traits from the Cerrado. LSW doses (0, 50, 150, 450, 600 m3 ha−1) were applied to the 0-0.20 m layer in a randomized design with three replicates. Post a 30-day incubation at 60% field capacity, the soil underwent mineralogical, physical (clay dispersed in water - CDW), chemical (sodium adsorption ratio - SAR, cation exchange capacity - CEC, base saturation - V%), and electrochemical (pH in H2O and KCl, ApH, point of zero charge - PZC, point of zero salt effect - PZSE, surface electric potential - iµo, and electrical conductivity - EC) analyses. The levels of exchangeable Ca, K, Mg, Na, and available P increased with increasing LSW doses. Increasing LSW doses in the soil led to an increase in EC, but soil salinization was not observed at the highest dose. With the application of LSW doses, there was a decrease in pH, ApH, PZSE, and an increase in CEC, PZC and ψo. Despite the increase in ψo, low clay dispersibility was observed. PHYSICAL OXISOL content (LSW Oxisols Oxisol s Cerrado 0, 0 (0 50 150 450 60 ha−1 ha1 ha 1 00.20 0020 0.20 20 0-0.2 replicates 30day day 30 mineralogical CDW, CDW , CDW) sodium SAR CEC V%, V V% V%) pH HO H O KCl ApH PZSE iµo EC analyses Ca K Mg Na dose ψo ( 5 15 45 6 ha− 00 00.2 002 020 0.2 2 0-0. 3 4 00. 02 0. 0-0 0-

This work evaluated the use of corncob as a support for the immobilization of an extracellular fructosyltransferase (E.C. 2.4.1.9) from Aspergillus oryzae IPT-301, aiming at the synthesis of a stable biocatalyst for the production of fructooligosaccharides. The transfructosylation activity of the immobilized enzyme was maximized via experimental design. Additionally, the biochemical properties and stability of the immobilized enzyme, as well as the reaction kinetics, were determined. The enzyme immobilized on alkali-treated corncob showed the highest transfructosylation activity at 50 °C and pH 5.5. It also presented a wide pH stability and a half-life around 1.4 times greater than the soluble enzyme. Furthermore, the immobilized enzyme showed 53% of retention of catalytic activity in a second consecutive reaction cycle, showing the potential for reuse. These results suggest that alkali-treated corncob is a promising support material for the synthesis of heterogeneous biocatalysts aiming at fructooligosaccharide production, which can contribute to the valorization of this abundant agro-waste. E.C. EC E C (E.C 2.4.1.9 2419 2 4 1 9 IPT301, IPT301 IPT 301, 301 IPT-301 fructooligosaccharides design Additionally kinetics determined alkalitreated alkali treated 5 55 5.5 halflife half life 14 1. Furthermore 53 cycle reuse agrowaste. agrowaste agro waste. waste agro-waste E.C 2.4.1. 241 IPT30 30 IPT-30 5. 2.4.1 24 IPT3 3 IPT-3 2.4. IPT- 2.4 2.

Seeking a viable alternative to fossil fuels as the primary energy source, bioethanol has emerged as a promising second-generation fuel derived from lignocellulosic biomass. With Brazil ranking pineapple as the third most produced fruit in temporary crops, this study aims to assess the impact of chemical pretreatment techniques, specifically organosolv and diluted acid, on the residual biomass of Pérola pineapple peel to enhance bioethanol production. Employing an experimental design that incorporates temperature, reaction time, and varying concentrations of organic solvent, the study examines their effects on the susceptibility of the substrate to saccharification for future bioethanol generation. Factors such as alphacellulose, hemicellulose, and lignin were evaluated in triplicate and subjected to statistical analysis using the Tukey test with a confidence level of 95%. Upon application of the pretreatment methods, it was observed that the organosolv solvent approach (utilizing water and ethanol) with sulfuric acid exhibited superior sugar conversion, yielding the highest concentration of xylose at 9.13 g L-1. Additionally, the pretreated biomass contained 1.38 g L 1 of cellobiose, 3.11 g L-1 of arabinose, and 3.76 g L-1 of glucose. This technique demonstrates promising potential for obtaining fermentable sugars crucial for bioethanol production. source secondgeneration second generation crops techniques production temperature time alphacellulose hemicellulose 95 95% methods utilizing ethanol conversion 913 9 13 9.1 L1. L1 1. Additionally 138 38 1.3 cellobiose 311 3 11 3.1 L- arabinose 376 76 3.7 glucose 91 9. 31 3. 37 7

The present work aims to extract and test cashew nut peel oil as a natural antioxidant in the oxidative stabilization of biodiesel. Therefore, determinations of the ideal time of Soxhlet and thermal extractions, Fourier transform infrared spectroscopy (FTIR) analyses, and evaluation of the oxidative stability by Rancimat method were carried out. FTIR analyses revealed that the 3rd cycle of extraction was sufficient to extract all the oil, with an average yield of 30.0%. For the thermal extraction of the laboratory technical cashew nut peel oil, the best extraction, based on statistical analysis, was 60 min, yielding 20.0%. The FTIR analysis of the extracted cashew nut peel oil showed characteristic peaks of phenolic groups and organic acids, showing differences in the intensities of the absorption bands. The oxidative stability showed induction period of 8 h 40 min for the hydraulic press extraction, 10 h 35 min for the Soxhlet extraction, and 10 h 65 min for the industrial technical extraction of the cashew nut peel oil. All values were below the 12-h limit established by the National Agency for Petroleum, Natural Gas and Biofuels (ANP). The technical cashew nut peel oil extracted in the laboratory presented an induction period of 11 h 12 min, close to that recommended by ANP, proving to be a promising natural antioxidant. Cardanol presented satisfactory results with 25 h 22 min, double that suggested by ANP. Thus, cashew nut peel oil showed important and promising results as a natural antioxidant for biodiesel. biodiesel Therefore extractions (FTIR out rd 300 30 0 30.0% 6 200 20 20.0% acids bands 4 1 3 12h Petroleum ANP . (ANP) 2 Thus 30.0 20.0 (ANP 30. 20.

This research aims to develop a precise and efficient dispersive solid-phase microextraction (DSPE) technique using third-generation polyamidoamine (PAMAM) dendrimer-grafted nanoparticles to quantify benzoylurea pesticides in green tea, black tea, and oolong tea infusions. The extraction efficiency is optimized through single-factor adjustments of key parameters, including adsorbent quantity (5-20 mg), adsorption duration (5-20 min), desorbent identity (methanol, acetonitrile), volume (100-600 μL), sodium chloride concentration (0-10%, m/v), and sample solution pH (3-8). The optimized method demonstrates linearity in the range of 2-500 μg L-1, with limits of detection (LODs) ranging from 0.6-1.5 μg L-1 and limits of quantification (LOQs) from 2.0 5.0 μg L-1. Recovery rates of 81.2-96.0% are achieved, with intra-day relative standard deviations (RSDs) of 1.4-2.8% and inter-day relative standard deviations of 2.0-3.9%, indicating high accuracy and repeatability. The successful application of detecting residues in commercial tea samples underscores the strong potential of the technique to determine benzoylurea analyte levels. solidphase solid phase DSPE (DSPE thirdgeneration third generation PAMAM (PAMAM dendrimergrafted dendrimer grafted infusions singlefactor single factor parameters 520 5 20 (5-2 mg, mg , mg) min, min min) methanol, methanol (methanol acetonitrile, acetonitrile acetonitrile) 100600 100 600 (100-60 μL, μL μL) 010%, 010 0 10%, 10 (0-10% m/v, mv m/v m v m/v) 38. 38 3 8 . (3-8) 2500 2 500 2-50 L1, L1 L 1, 1 LODs (LODs 0.61.5 0615 0.6 1.5 6 0.6-1. L- LOQs (LOQs 2. 50 5. L1. 1. 81.296.0% 812960 81.2 96.0% 81 96 81.2-96.0 achieved intraday intra day RSDs (RSDs 1.42.8% 1428 1.4 2.8% 4 1.4-2.8 interday inter 2.03.9%, 2039 3.9%, 9 2.0-3.9% repeatability levels 52 (5- 10060 60 (100-6 010% 01 10% (0-10 (3-8 250 2-5 61 0.61. 061 06 0. 15 0.6-1 296 81.296.0 81296 812 81. 960 96.0 81.2-96. 42 1.42.8 142 14 28 2.8 1.4-2. 03 2.03.9% 203 39 3.9% 2.0-3.9 (5 1006 (100- (0-1 (3- 25 2- 0.61 0.6- 29 81.296. 8129 96. 81.2-96 1.42. 1.4-2 2.03.9 3.9 2.0-3. ( (100 (0- (3 81.296 81.2-9 1.42 1.4- 2.03. 3. 2.0-3 (10 (0 81.29 81.2- 2.03 2.0- (1

ABSTRACT Biochar can promote crop production and soil quality. However, its characteristics depend on the waste used in its production and its effects may vary according to the species being cultivated and the management adopted. The aim of this study was to evaluate the application of biochar from animal waste on soil quality and the agronomic characteristics of the cowpea. An experiment was set up to test three types of biochar (bovine-BB, swine-SB and poultry-BP), with added fertiliser (BBF, SBF and BPF) and two control treatments, including the addition of calcium magnesium oxide (CT) and calcium magnesium oxide with fertiliser (CTF), giving a total of eight treatments with four replications. There was a respective increase of up to 102.94%, 1048%, 1560% and 360.22% in stem diameter, number of pods, number of grains per pod and stem dry matter from adding the biochar. The poultry biochar increased each of the above parameters even with no added fertiliser. There was no difference in basal soil respiration or β-glucosidase enzyme activity, whereas organic carbon (TOC), total nitrogen (TN), microbial carbon and soil labile carbon were greater with biochar. BBF gave the highest TOC content (24.40 g kg-1), while BP and BPF increased TN by around 61%. The application of biochar + fertiliser contributed to an average reduction of 56% in the soil metabolic quotient. Poultry biochar favoured both the agronomic characteristics of the cowpea and soil quality, while bovine biochar showed more marked results with the addition of fertiliser. However adopted bovineBB, bovineBB BB, BB (bovine-BB swineSB swine SB poultryBP, poultryBP , poultry-BP) BBF, (BBF CT (CT CTF, CTF (CTF) replications 10294 102 94 102.94% 1048 1048% 1560 36022 360 22 360.22 diameter pods βglucosidase β glucosidase activity TOC, (TOC) TN, (TN) 24.40 2440 24 40 (24.4 kg1, kg1 kg 1 kg-1) 61 61% 56 quotient poultry-BP (CTF 1029 10 9 102.94 104 156 3602 36 2 360.2 (TOC (TN 24.4 244 4 (24. kg-1 6 5 102.9 15 3 360. 24. (24 kg- 102. (2 (

We report a facile hydrothermal method for the synthesis of niobium pentoxide (Nb2O5) under two different temperatures, 120 °C (Nb2O5-120) and 150 °C (Nb2O5-150). The obtained materials were characterized by structural, optical and morphological techniques. Also, the photocatalytic properties of the Nb2O5 samples were evaluated in two reactions under ultraviolet (UVC) irradiation: degradation of methylene blue (MB) and indigo carmine (IC) dyes; and esterification of free fatty acids (FFA) present in waste cooking oil (WCO). The Nb2O5 was formed at different temperatures of synthesis, and the increase in temperature did not cause significant changes in the structural and optical characteristics, but resulted in an increased surface area of the synthesized materials. Both synthesized materials showed excellent efficiency for dye photodegradation. The sample Nb2O5-150 presented the best performance for the MB photodegradation, with almost 85% of the removal efficiency. In this case, the adsorption of MB molecules on the surface of the material was high due to the favorable electrostatic interaction and also because of its high surface area. For the IC photodegradation, the adsorption was insignificant, and both samples presented approximately 100% of the removal efficiency. These materials were also promising for the reduction of free fat acids in waste oil by photoesterification. NbO Nb O (Nb2O5 12 C Nb2O5120 (Nb2O5-120 15 Nb2O5150. Nb2O5150 . (Nb2O5-150) techniques Also Nb2O UVC (UVC irradiation (MB (IC dyes FFA (FFA WCO. WCO (WCO) characteristics photodegradation Nb2O5-15 85 case insignificant 100 photoesterification (Nb2O 1 Nb2O512 (Nb2O5-12 Nb2O515 (Nb2O5-150 (WCO Nb2O5-1 8 10 Nb2O51 (Nb2O5-1 (Nb2O5-15 Nb2O5- (Nb2O5-

Phosphate species can affect aquatic ecosystems, as excess of this nutrient can cause eutrophication, generating environmental impacts. Lamellar double hydroxides have shown promise in removing phosphate at low concentrations (10-50 mg L 1). In this context, lamellar double hydroxides were synthesized interspersed with nitrates and humic substances, searching for a new product that favors phosphorus adsorption. X-ray diffraction showed the presence of characteristic peaks of lamellar double hydroxides and thermogravimetric analysis showed the decomposition behavior of lamellar structure. The adsorption capacity occurred quickly (< 30 min), being more efficient for lamellar double hydroxides with NO3. The maximum adsorption capacity showed results of 35.03 and 44.20 mg g 1 for lamellar double hydroxides with humic substances and lamellar double hydroxides with NO3, respectively. The complexation capacity showed that pH directly influences complexation, being greater for lamellar double hydroxides with humic substances at pH 6.5. Thus, nanostructured materials with humic substances are promising for use in contaminant remediation and adsorption can be a fast and efficient technique for use in soil and water. ecosystems eutrophication impacts 1050 10 50 (10-5 1. . 1) context Xray X ray structure < ( 3 min, min , min) NO3 NO 3503 35 03 35.0 4420 44 20 44.2 respectively 65 6 5 6.5 Thus water 105 (10- 350 0 35. 442 4 2 44. 6. (10 (1

ABSTRACT Purpose: This study aimed to determine whether early-stage intraocular pressure can be modulated using a thermal face mask. Methods: In this prospective clinical study, healthy participants were randomized on a 1:1:1 allocation ratio to three mask groups: hypothermic (G1), normothermic (G2), and hyperthermic (G3). After randomization, 108 eyes from 108 participants were submitted to clinical evaluations, including measurement of initial intraocular pressure (T1). The thermal mask was then applied for 10 minutes, followed by a second evaluation of intraocular pressure (T2) and assessment of any side effects. Results: The hypothermic group (G1) showed a significant reduction in mean intraocular pressure between T1 (16.97 ± 2.59 mmHg) and T2 (14.97 ± 2.44 mmHg) (p<0.001). G2 showed no significant pressure difference between T1 (16.50 ± 2.55 mmHg) and T2 (17.00 ± 2.29 mmHg) (p=0.054). G3 showed a significant increase in pressure from T1 (16.53 ± 2.69 mmHg) to T2 (18.58 ± 2.95 mmHg) (p<0.001). At T1, there was no difference between the three study groups (p=0.823), but at T2, the mean values of G3 were significantly higher than those of G1 and G2 (p<0.00). Conclusion: Temperature was shown to significantly modify intraocular pressure. Thermal masks allow the application of temperature in a controlled, reproducible manner. Further studies are needed to assess the duration of these effects and whether they are reproducible in patients with pathologies that affect intraocular pressure. Purpose earlystage early stage Methods 111 1 1:1: G1, G , G2, (G2) G3. . (G3) randomization evaluations T1. T (T1) minutes (T2 Results (G1 16.97 1697 16 97 (16.9 259 2 59 2.5 mmHg 14.97 1497 14 (14.9 244 44 2.4 p<0.001. p0001 p p<0.001 0 001 (p<0.001) 16.50 1650 50 (16.5 255 55 17.00 1700 17 00 (17.0 229 29 2.2 p=0.054. p0054 p=0.054 054 (p=0.054) 16.53 1653 53 269 69 2.6 18.58 1858 18 58 (18.5 295 95 2.9 p=0.823, p0823 p=0.823 823 (p=0.823) p<0.00. p000 p<0.00 (p<0.00) Conclusion controlled manner 11 1:1 (G2 (G3 (T1 (T (G 16.9 169 9 (16. 25 5 2. 14.9 149 (14. 24 4 (p<0.001 16.5 165 17.0 170 (17. 22 p005 p=0.05 05 (p=0.054 26 6 18.5 185 (18. p082 p=0.82 82 (p=0.823 p00 p<0.0 (p<0.00 1: 16. (16 14. (14 17. (17 p=0.0 (p=0.05 18. (18 p08 p=0.8 8 (p=0.82 p0 p<0. (p<0.0 (1 p=0. (p=0.0 (p=0.8 p<0 (p<0. ( p=0 (p=0. p< (p<0 p= (p=0 (p< (p= (p

ABSTRACT Purpose: This study aimed to analyze variations in intraoperative corneal thickness during corneal cross-linking in patients with keratoconus and to investigate its possible correlation with presurgical maximal keratometry (Kmax) and pachymetry. Methods: This was a prospective case series. We used a method similar to the Dresden protocol, with the application of hydroxypropyl methylcellulose 0.1% hypo-osmolar riboflavin in corneas between 330 and 400 µm after epithelium removal. Corneal thickness was measured using portable calipers before and immediately after epithelium removal, and 30 and 60 min after the procedure. Results: The 30 patients in this study were followed up for one year. A statistically significant difference was observed in pachymetry values during the intraoperative period (p<0.0001) and an increase of 3.05 µm (95%C1: 0.56-5.54) for each diopter was seen after epithelium removal (p0.019). We found an average Kmax difference of —2.12 D between men and women (p0.013). One year after treatment, there was a statistically significant reduction in pachymetry (p<0.0001) and Kmax (p0.0170) values. Conclusions: A significant increase in pachymetry measurements was seen during the procedure, and most patients showed a regression in Kmax and pachymetry values one year after surgery. Purpose crosslinking cross linking (Kmax Methods series protocol 01 0 1 0.1 hypoosmolar hypo osmolar 33 40 3 6 procedure Results p<0.0001 p00001 p 0001 (p<0.0001 305 05 3.0 95%C1 95C1 C 95 C1 (95%C1 0.565.54 056554 0.56 5.54 56 5 54 0.56-5.54 p0.019. p0019 p0.019 . p0 019 (p0.019) 2.12 212 2 12 —2.1 p0.013. p0013 p0.013 013 (p0.013) treatment p0.0170 p00170 0170 (p0.0170 Conclusions surgery 0. 4 p<0.000 p0000 000 (p<0.000 3. 95%C 95C 9 (95%C 565 0.565.5 05655 056 0.5 554 5.5 0.56-5.5 p001 p0.01 (p0.019 2.1 21 —2. (p0.013 p0.017 p0017 017 (p0.017 p<0.00 p000 00 (p<0.00 0.565. 0565 55 5. 0.56-5. p00 p0.0 (p0.01 2. —2 p<0.0 (p<0.0 0.565 0.56-5 p0. (p0.0 — p<0. (p<0. 0.56- (p0. p<0 (p<0 (p0 p< (p< (p