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Interstitial nitrogen titanium dioxide (N–TiO2 ) has been synthesized from solid-state microwave irradiation of commercial TiO2 (P25) and urea, which is in contrast to other solid-state methods that give substitutional N–TiO2 . N–TiO2 was characterized by powder X-ray diffraction (XRD), N2 -adsorption surface area measurement, Fourier transformed infra-red (FTIR), X-ray photoelectron spectroscopy (XPS) and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). FTIR, XPS and UV-Vis DRS indicate that interstitial doping of N has occurred in the TiO2 lattice. Ti–O–N detected by FTIR at 1,449 cm–1 contributed to the N–O bond. There is no C=O bond in N–TiO2 showing that urea was completely decomposed in modified TiO2 . This N–O bond is also proved by XPS on deconvolution peaks detected at 404.8 and 531.5 eV in N 1s and O 1s, respectively. UV-Vis DRS analysis revealed the formation of N 2p state ca. 0.12 eV above valence band in N–TiO2 and it is almost similar to characteristic of substitutional N–TiO2 . Thus, the combination of substitutional and interstitial called interstitial N 2p is suggested in our prepared N–TiO2 sample. The photocatalytic activities of N–TiO2 and pristine TiO2 were compared for the photodegradation of the dye reactive red 4 (RR4) under visible light irradiation from an LED source. Complete bleaching occurred within 60 min using N–TiO2 whereas no photocatalytic degradation was observed using pristine TiO2 . [ABSTRACT FROM AUTHOR]

A commercially available TiO2 (P25) was modified to produce nitrogen (N) doped TiO2 prepared by mixing TiO2 powder with various amounts of urea as N precursor using a microwave irradiation heating technique. X-ray photoelectron spectroscopy analysis showed that N chemically bonded with TiO2 produces Ti-N. The measured band gap energy (Eg) of the modified sample was ca. 2.9 eV as detected by UV-Vis/DRS. The optimum modified N doped TiO2 denoted as U3-800 prepared at 230 WC showed an active visible light photoactivity. This observation shows that microwave irradiation is able to form Ti-N at low temperature whereas this previously could not be achieved under conventional heating using a muffle furnace at the same temperature. U3-800 showed visible light active photodegradation for 30, 10 and 5 mg L-1 of reactive red 4, crystal violet and Janus green dyes, respectively, in less than 105 min to complete decolorization under suspension mode while no photocatalytic activity was observed under pristine TiO2 under the same conditions. Immobilization of a U3-800 sample was carried out using DSAT as a thin layer binder and the photoactivity of Immobilize/U3-800/DSAT is comparable with the suspension mode. Surprisingly, immobilized/U3-800 has a strong coating with glass support material and can be continuously used for 30 cycles without affecting photoactivity performance. [ABSTRACT FROM AUTHOR]

In this study the degradation of Methyl Orange, using Fenton reaction was studied and optimized using central composite design as a response surface methodology. The effects of various experimental parameters in this reaction were investigated using central composite design. 28 experiments, with 4 factors and 5 levels for each factor were designed. These factors (or variables) were: initial concentration of Fe (II), initial concentration of H2O2, initial concentration of oxalate and the reaction time. A full-quadratic polynomial equation between the percentage of dye degradation (as a response) and the studied parameters was established. After removing the non-significant variables from the model, response surface method was used to obtain the optimum conditions. The optimum ranges of variables were: 0.25 - 0.35 mM for initial concentration of Fe (II), 5-17 mM for initial concentration of H2O2, 4-9 mM for initial concentration of oxalate, and 50-80 min for the reaction time. Also the results of extra experiments showed that these optimized values can be used for real samples and yield to a high value for the response.

The article announces the retraction of the article "The Important Role of Matrix Metalloproteinases in Nematode Parasites" that was published in the September 2014 issue of the journal.

Background: Extensive research has explored the role of gut microbiota in multiple sclerosis (MS). However, the impact of microbial communities in the oral cavity and respiratory tract on MS is an emerging area of investigation., Purpose: We aimed to review the current literature related to the nasal, oral, and lung microbiota in people with MS (PwMS)., Methods: We conducted a narrative review of clinical and preclinical original studies on PubMed that explored the relationship between the bacterial or viral composition of the nasal, lung, and oral microbiota and MS. Additionally, to find relevant studies not retrieved initially, we also searched for references in related review papers, as well as the references cited within the included studies., Results and Conclusions: Thirteen studies were meticulously reviewed in three sections; oral microbiota (n = 8), nasal microbiota (n = 3), and lung microbiota (n = 2), highlighting considerable alterations in the oral and respiratory microbiome of PwMS compared to healthy controls (HCs). Genera like Aggregatibacter and Streptococcus were less abundant in the oral microbiota of PwMS compared to HCs, while Staphylococcus, Leptotrichia, Fusobacterium, and Bacteroides showed increased abundance in PwMS. Additionally, the presence of specific bacteria, including Streptococcus sanguinis, within the oral microbiota was suggested to influence Epstein-Barr virus reactivation, a well-established risk factor for MS. Studies related to the nasal microbiome indicated elevated levels of specific Staphylococcus aureus toxins, as well as nasal glial cell infection with human herpes virus (HHV)-6 in PwMS. Emerging research on lung microbiome in animal models demonstrated that manipulating the lung microbiome towards lipopolysaccharide-producing bacteria might suppress MS symptoms. These findings open avenues for potential therapeutic strategies. However, further research is crucial to fully understand the complex interactions between the microbiome and MS. This will help identify the most effective timing, bacterial strains, and modulation techniques., Competing Interests: Declaration of competing interest There are no financial/ personal relationships with any people or organizations that could inappropriately influence this study. There are no potential competing interests including employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications/registrations, and grants or other funding., (Copyright © 2024 Elsevier B.V. All rights reserved.)