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Ag2CrO4 is a representative member of a family of Ag-containing semiconductors with highly efficient visible-light-driven responsive photocatalysts. The doping process with Eu3+ is known to effectively tune their properties, thus opening opportunities for investigations and application. Here, we report the enhancement of the photocatalytic activity and stability of Ag2CrO4 by introducing Eu3+cations. The structural, electronic, and photocatalytic properties of Ag2CrO4:xEu3+ (x = 0, 0.25, 0.5, 1%) synthesized using the coprecipitation method were systematically discussed, and their photodegradation activity against rhodamine B (RhB), ciprofloxacin hydrochloride monohydrate (CIP), and 4-nitrophenol (4-NP) was evaluated. Structural analyses reveal a short-range symmetry breaking in the Ag2CrO4 lattice after Eu3+ doping, influencing the material morphology, size, and electronic properties. XPS analysis confirmed the incorporation of Eu3+ and alteration of the surface oxygen species. Furthermore, photoluminescence measurements indicated that the doping process was responsible for reducing recombination processes. The sample doped with 0.25% Eu3+ exhibited superior photocatalytic performance compared to pure Ag2CrO4. Scavenger experiments revealed an increase in the degradation via •OH reactive species for the sample doped with 0.25% Eu3+. DFT calculations provided atomic-scale insights into the structural and electronic changes induced by the Eu3+ doping process in the Ag2CrO4 host lattice. This study confirms that Eu3+ doping alters the band structure, enabling different degradation paths and boosting the separation/transfer of photogenerated charges, thereby improving the overall photocatalytic performance.

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The catalytic performance of modified hydroxyapatite nanoparticles, Ca10-xFex-yWy(PO4)6(OH)2, was applied for the degradation of methylene blue (MB), fast green FCF (FG) and norfloxacin (NOR). XPS analysis pointed to the successful partial replacement of Ca by Fe. Under photo-electro-Fenton process, the catalyst Ca4FeII1·92W0·08FeIII4(PO4)6(OH)2 was combined with UVC radiation and electrogenerated H2O2 in a Printex L6 carbon-based gas diffusion electrode. The application of only 10 mA cm-2 resulted in 100% discoloration of MB and FG dyes in 50 min of treatment at pH 2.5, 7.0 and 9.0. The proposed treatment mechanism yielded maximum TOC removal of ∼80% and high mineralization current efficiency of ∼64%. Complete degradation of NOR was obtained in 40 min, and high mineralization of ∼86% was recorded after 240 min of treatment. Responses obtained from LC-ESI-MS/MS are in line with the theoretical Fukui indices and the ECOSAR data. The study enabled us to predict the main degradation route and the acute and chronic toxicity of the by-products formed during the contaminants degradation.

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Photoelectrochemical systems utilizing solar energy have garnered significant attention for their sustainability in remediating contaminated water. This study focuses on advancing photoanode development through the utilization of carbon nitrides (C3N4) and bismuth vanadate (BiVO4), two promising semiconductor materials renowned for their efficient electron-hole pair separation leading to enhanced photocatalytic activity. Four distinct materials were synthesized and compared: BiVO4 over C3N4, C3N4 over BiVO4, and pristine BiVO4 and C3N4. Upon electrochemical analysis, the C3N4-BiVO4 heterostructure exhibited the highest photoelectrocatalytic charge transfer constant, mobility, and lifetime of charge carriers. Capitalizing on these exceptional properties, the composite was applied to remove organic matter real effluent from the textile industry. The photoelectrodegradation of the effluent demonstrated substantial removal of Total Organic Carbon (TOC) and the generation of low toxicity degradation products, accompanied by low energy consumption. The compelling results underscore the high potential of the synthesized C3N4-BiVO4 heterostructure for industrial applications, particularly in addressing environmental challenges associated with textile industry effluents.

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As well established in the literature, residual toxicity is an important parameter for evaluating the sanitary and environmental safety of water treatment processes, and this parameter becomes even more crucial when chlorine-based processes are applied for water treatment. Eliminating initial toxicity or preventing its increase after water treatment remains a huge challenge mainly due to the formation of highly toxic disinfection by-products (DBPs) that stem from the degradation of organic contaminants or the interaction of the chlorine-based oxidants with different matrix components. In this review, we present a comprehensive discussion regarding the toxicological aspects of water treated using chlorine-based advanced oxidation processes (AOPs) and the recent findings related to the factors influencing toxicity, and provide directions for future research in the area. The review begins by shedding light on the advances made in the application of free chlorine AOPs and the findings from studies conducted using electrochemical technologies based on free chlorine generation. We then delve into the insights and contributions brought to the fore regarding the application of NH2Cl- and ClO2-based treatment processes. Finally, we broaden our discussion by evaluating the toxicological assays and predictive models employed in the study of residual toxicity and provide an overview of the findings reported to date on this subject matter, while giving useful insights and directions for future research on the topic.

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Water contamination by contaminants of emerging concern is one of the main challenges to be solved by our desired sustainable society. In the same time, different technologies for water treatment are becoming enough mature to be implemented. In this work, two different advanced oxidation processes (AOP) were investigated: i) electrochemical processes (electrochemical, photoassisted electrochemical, electro Fered-Fenton, and photo-electro Fered-Fenton - PEF-Fered) using a BDD and DSA® electrodes under UVA and UVC irradiation (9 W) and ii) solar-based AOP using four distinct oxidants (HOCl, H2O2, S2O82-, HSO5-) in the presence or absence of Fe2+ ions to oxidize and mineralize imidacloprid (IMD: 50 mg L-1) containing solutions. The PEF-Fered (1.0 mM Fe2+ and 50 mg L-1 h-1 H2O2) under UVA or UVC irradiation and HOCl/UVC (NaCl 17 mM) processes using a BDD and DSA® electrodes (10 mA cm -2), respectively, performed equally well to completely oxidize and mineralize (∼90%) IMD at the expense of only ∼0.3 kWh g-1. Low amounts and highly oxidized byproducts identified through liquid chromatography tandem mass spectrometry were observed for the HOCl/UVC process using a DSA® electrode. Concerning the solar-based AOP, all assessed oxidants (4 mM h-1) successfully oxidized IMD within 3 h of treatment, whereas only H2O2 and HOCl led to significant (∼60%) TOC abatement after 6 h treatment. The use of Fe2+ (0.5 or 1.0 mM) had no significant improvement in the oxidation and mineralization of IMD.

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BACKGROUND: Dorsal wrist ganglia are the most common soft tissue tumor type of the upper limb. Surgical resection, open or arthroscopic, is one of the most frequent procedures performed by hand surgeons. This study sought to perform an objective evaluation of the outcomes of arthroscopic resection of dorsal wrist ganglia and their recurrence rates over 4 years. Patients treated with arthroscopic resection were expected to have favorable outcomes and low complication rates after 4 years of follow-up. METHODS: We evaluated 34 cases of dorsal wrist ganglia in patients who underwent arthroscopic resection. The patients were evaluated using the Quick-Disabilities of the Arm, Shoulder and Hand (QuickDASH) outcome measure, visual analog scale (VAS) for pain, range of motion of the wrist, palmar grip strength, rates of recurrence, and complications. RESULTS: During the postoperative period, the QuickDASH score averaged 2.3 points, the mean residual pain by VAS was 0.54, full range of wrist movement was recovered by all patients, and the mean palmar grip strength was 29.4 kgf; there was 1 case with recurrence. There were no severe postoperative complications throughout the follow-up period. CONCLUSIONS: The outcomes, recurrence, and complications rates after 4 years of follow-up presented in this study support the use of arthroscopy as a treatment for dorsal wrist ganglion.

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This aim of this study was to evaluate the progression of grip, tip pinch, key (lateral) pinch, and tripod pinch strengths in patients suffering from carpal tunnel syndrome with thenar atrophy following surgery. Between October 2008 and May 2010, 46 patients (49 hands) with carpal tunnel syndrome associated with thenar atrophy underwent surgery. Thenar atrophy was assessed by clinical inspection. Evaluations for grip strength and for tip, key, and tripod pinch strengths were made using a hydraulic hand dynamometer grip and a hydraulic pinch gauge, respectively. These measurements were taken before surgery and at 3 and 6 months after the procedure. When we compared the averages of all forces measured in the affected hand before the surgery with all forces measured at 3 months postoperative, we found no significant differences. However, after 6 months, we found significant differences for all four strength tests as compared with those measurements taken preoperatively and at the 3 month time point. Our results suggest that patients with thenar atrophy show increased grip strength and pinch strength by the sixth month after surgical treatment.

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Melorheostosis of the hand is rare. We report a 28-year-old woman with persistent pain associated with a slowly growing mass on the dorsum of the right thumb. The radiographs, computed tomography, and magnetic resonance imaging were used to examine characteristic of melorheostosis involving the trapezium bone, first metacarpal, and proximal phalange. The lesions underwent a surgical debulking of the hyperostotic cortex and a cortical fenestration.