Expression of concern: Acceleration of ammonium phosphate hydrolysis using TiO2 microspheres as a catalyst for hydrogen production.

Expression of concern for 'Acceleration of ammonium phosphate hydrolysis using TiO2 microspheres as a catalyst for hydrogen production' by Ayman H. Zaki et al., Nanoscale Adv., 2020, 2, 2080-2086, https://doi.org/10.1039/D0NA00204F.

Cobalt-ferrite/Ag-fMWCNT hybrid nanocomposite catalyst for efficient degradation of synthetic organic dyes via peroxymonosulfate activation.

The activation of peroxymonosulfate (PMS) by nanocatalysts has shown promise as an effective wastewater treatment protocol. Magnetic CoFe2O4/Ag-nanoparticles (NPs) anchored on functionalized multiwalled carbon nanotubes (fMWCNTs), a support material, were synthesized using a one-pot solvothermal method. The surface morphologies and physicochemical properties of the CoFe2O4/Ag-fMWCNT hybrid nanocomposite catalyst were investigated by powder X-ray diffraction analysis, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption-desorption isotherms. The activity of the nanocomposite combined with PMS (serving as an activator) toward the degradation of rhodamine B, methylene blue, methyl orange, and methyl red was investigated. The obtained optimal 0.02 g CoFe2O4/Ag-fMWCNTs exhibited the highest PMS activation performance, with a removal percentage of 100% for 20 ppm dye concentration at pH 6.5 within 14 min. In addition, the rhodamine B degradation product was investigated by analyzing the intermediate products by liquid chromatography/mass spectrometry (LC-MS). The homogeneous distribution of CoFe2O4/Ag NPs on fMWCNTs accelerated PMS activation and enhanced the catalytic degradation of dyes. The effects of the reaction parameters on the dye degradation efficiency were investigated by using different nanocatalysts (fMWCNTs, CoFe2O4/fMWCNTs, and CoFe2O4/Ag-fMWCNTs) as well as by varying the pH (3-11), dye concentration (10-50 mg/l), catalyst dose (0.002-0.3 g), and PMS dose (0.02-0.1 g). Quenching experiments revealed that sulfate radicals are primarily responsible for rhodamine B degradation. A plausible mechanism for catalytic PMS activation was also proposed. Complete decolorization occurred within the first few minutes of the reaction. Furthermore, the catalytic activity of the CoFe2O4/Ag-fMWCNT/PMS hybrid nanocomposite remained stable after five successive cycles. This study verifies the applicability of CoFe2O4/Ag-fMWCNTs as an ultrafast catalyst for the complete removal of persistent organic pollutants via PMS activation, revealing their promising application in wastewater treatment.

Acceleration of ammonium phosphate hydrolysis using TiO2 microspheres as a catalyst for hydrogen production.

Titania microspheres are considered an adequate material with low cost and easily attainable pathways, and can be utilized in photocatalytic H2 production to solve the energy crisis. Spherical porous titanium dioxide materials, with nanostructure composition, were chemically synthesized from titanate nanotubes via a simple hydrothermal technique, then added as a catalyst to accelerate the route of ammonium phosphate hydrolysis for hydrogen production. The mechanism of sphere formation from titanate nanotubes is elucidated in detail through the current study. The prepared materials were applied as a photocatalyst to facilitate the separation and transfer of photoinduced electrons, while preventing the recombination of electron-hole pairs. Experimental results show that the obtained microspheres possess significantly enhanced photocatalytic hydrogen (H2) production performance. The amount of photocatalytic hydrogen product using the microspheres is found to be ∼2.5 fold greater than that of titanate nanotubes. Analytical techniques such as field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HR-TEM), simulated visible solar light and X-ray diffraction (XRD) were used for the evaluation and characterization of the developed products, as well as the elucidation of the route of hydrolysis in the hydrogen production process.

Influence of nitrogen excited species on the destruction of naphthalene in nitrogen and air using surface dielectric barrier discharge.

The destruction of naphthalene, as representative polycyclic aromatic hydrocarbons, by surface dielectric barrier discharge is investigated in air as well as dry and humidified nitrogen at ambient temperature. Naphthalene destruction efficiency is evaluated in terms of chemical change vis-a-vis energy utilization. The detected byproducts are qualitatively evaluated in order to understand the role of the active species in the destruction process. The results show that the destruction efficiency and the energy efficiency are higher in the dry nitrogen than in the humidified nitrogen, and these decrease with the increase of the humidity. Measured concentration of ozone as a byproduct qualitatively indicates the roles of oxygen and ozone in the destruction process in air. The analysis of the aerosol particles formed during the destruction process, both in the dry and humidified nitrogen, confirmed the adverse effects of the humidity on the byproducts formation and subsequently on the destruction process.

Effect of lead nitrate on the liver of the cichlid fish (Oreochromis niloticus): a light microscope study.

The adverse impacts of heavy metals on fish liver were evident with great variability among organs and species. The present study deals with the histological changes of the hepatocytes of the Nile tilapia, Oreochromis niloticus, following exposure to 2.5, 5, 10 ppm of lead nitrate for 1, 2, 3, 4 weeks. The present results revealed that lead nitrate exerts some histological effects on the hepatic tissue after exposure to the first concentration in the form of dilatation and congestion of the blood vessels, vacuolation of hepatic cells, proliferation of connective tissue and hepatic necrosis. Leucocyte aggregation-mostly lymphatic in nature-was seen infiltrating hepatic tissue. These alterations became more pronounced in liver of fishes exposed to second concentrations indicating more progressive signs of necrosis. The presence of eosinophilic oedematous areas surrounding some blood vessels was also observed. Finally, at the third concentration, in addition to the above alterations, melanomacrophages, which store lipofuscin at the site of necrosis, were observed. These histological results imply that the fish liver may serve as a target organ for the toxicity of sublethal concentrations of lead nitrate.

The Arabic vowels: features and possible clinical application in communication disorders.

UNLABELLED: Most scholars, old and modern, agree that the vowel system of the Arabic language is composed of 3 vowels only, namely /i/, /ε/ and /u/. The spoken Cairo dialect suggests that there are 6 identifiable vowels, with a short and long variant for each. OBJECTIVE: The aim of this study is to test the validity of the notion that there are 6 × 2 distinct vowels, with a more central one. SUBJECTS AND METHODS: Spectral analysis was used to measure F(1) and F(2) for the vowels of 14 real words. Data was collected from 60 healthy adult informants, 30 males and 30 females. They were native Egyptians speaking the colloquial Cairene dialect. RESULTS: The values of the 6 long and short vowels plus the central one are presented. A significant difference was found between each of them. The long and short vowels differed only in the duration but did not differ in their formant values. CONCLUSION: The study illustrates the distinctive features of the vowels of the Arabic language. Each of the 7 vowels represents a distinct entity. This will have important implications in assessment and management of language, speech and voice disorders in children and adults.

Salivary anti-Helicobacter pylori positivity among endoscopy patients with chronic liver disease.

In this study, endoscopy patients with and without chronic liver disease (CLD) were examined and tested for Helicobacter pylori infection by detecting the presence of serum and salivary anti-H. pylori antibody. The validity of these measures was compared with Campylobacter-like organism analysis (gold standard) performed on patients requiring gastric biopsy. Among 114 patients with CLD and 50 without, the commonest endoscopy diagnosis was gastritis (27.2%). Salivary H. pylori positivity was significantly associated with older age. Salivary anti-H. pylori antibody positivity showed low sensitivity (36.6%) and high specificity (75.8%) in CLD patients.

Salivary anti-Helicobacter pylori positivity among endoscopy patients with chronic liver disease

In this study, endoscopy patients with and without chronic liver disease [CLD] were examined and tested for Helicobacter pylori infection by detecting the presence of serum and salivary anti-H. pylori antibody. The validity of these measures was compared with Campylobacter-like organism analysis [gold standard] performed on patients requiring gastric biopsy. Among 114 patients with CLD and 50 without, the commonest endoscopy diagnosis was gastritis [27.2%]. Salivary H. pylori positivity was significantly associated with older age. Salivary anti-H. pylori antibody positivity showed low sensitivity [36.6%] and high specificity [75.8%] in CLD patients

Sperm disomy in idiopathic severely oligoasthenoteratozoospermic males.

This work aimed to determine the incidence of sperm disomy in infertile men with idiopathic severe oligoasthenoteratozoospermia (OAT). Fifty male subjects were included in this study: 30 infertile men with idiopathic severe OAT and 20 healthy fertile men as controls. Semen analysis, hormonal assay (follicle-stimulating hormone, luteinising hormone and testosterone), scrotal ultrasound examination and fluorescent in situ hybridisation of their semen samples were performed to determine the disomy levels of chromosomes X and Y. There was a significant higher frequency for XX disomy and XY disomy in spermatozoa from severe OAT patients than that in controls. There was nonsignificant difference in the percentage of YY disomy between OAT cases and controls. XX, YY and XY disomy showed nonsignificant correlation with the age. Sperm concentration and sperm motility demonstrated significant negative correlation with XX and XY disomy. Sperm abnormal forms had significant negative correlation with XX and XY disomy. Nonsignificant correlation was demonstrated between YY disomy and semen parameters. XX disomy showed significant positive correlation with XY disomy and nonsignificant correlation with YY disomy. YY disomy showed nonsignificant correlation with XY disomy. It is concluded that sperm disomy in severe OAT is increased, which should be taken into account when undergoing micromanipulation.

Transmission-line electric field induction in humans using charge simulation method.

This paper is aimed at determining the distribution of the fields, induced charges, and currents on a human body standing in the high electric fields produced by high voltage overhead transmission lines. This method of analysis is based on the charge simulation technique. This will serve to explain the biological studies of possible long-term exposure effects to electric fields.

Topical minoxidil in alopecia areata: no effect on the perifollicular lymphoid infiltration.

The therapeutic value of topical minoxidil in alopecia areata (AA) has been investigated in recent years, with variable results. Although the mechanism whereby minoxidil may stimulate hair regrowth in some cases of AA has not yet been elucidated, there have been reports of a decrease in the perifollicular infiltrates of mononuclear leukocytes (MNC)--particularly T lymphocytes--that characterize this condition, in patients "responding" to topical minoxidil. In a randomized and double-blind study, we have investigated the effect of 5% topical minoxidil versus placebo (vehicle alone) on the extent and composition of the perifollicular MNC infiltration in 20 patients having extensive AA (26-99% scalp hair loss). The proportions of hair follicles showing perifollicular infiltration by MNC and their main subsets were determined with histologic and immunohistochemical stainings of scalp biopsies obtained before treatment, after 12 weeks of randomized double-blind minoxidil versus placebo treatment, and after 12 additional weeks during which all patients received minoxidil. Six of the patients showed cosmetically acceptable hair regrowth (CAHR) at the end of the 24 weeks and this was associated with a significant decrease in the proportions of follicles infiltrated by total T and B lymphocytes, macrophages, and Langerhans cells at week 12, and by total T lymphocytes at week 24. However, no significant differences in the extent or composition of the perifollicular infiltrates were detected at week 12 between patients receiving minoxidil and placebo, or between the week-12 and week-24 biopsies of those patients who first received placebo and then minoxidil. These findings indicate that in AA the reduction in perifollicular T-cell infiltration associated with CAHR is not attributable to an effect of topical minoxidil.

Which oral white lesions will become malignant? An image cytometric study.

We investigated the value of image cytometry in predicting the prognosis of oral epithelial lesions, whether or not they show dysplasia. Thirty-five oral epithelial lesions were studied retrospectively. Of these, 23 had later transformed to carcinoma and 12 had not. By means of the Leitz TAS image analyzer, 200 nuclei of epithelial cells and 20 nuclei of lymphocytes from each section were individually assessed for eight features related to shape and amount of stain and for six features related to chromatin pattern. The mean, standard deviation, and interquartile range of each feature were calculated, first for each section and then for each group. With the use of linear stepwise discriminant analysis we constructed a predictive model, which consisted of three variables related to chromatin pattern. The variables were mean margination, standard deviation of clumping, and standard deviation of condensation. In the jackknife classification, this model predicted the malignant potential of the lesions that later transformed to cancer with 86% predictive value and 83% sensitivity.

An unusual cause of stridor following anaesthesia requiring tracheostomy.

A 75-year-old woman underwent panendoscopy and excision of a neck "lump". After antagonism of residual neuromuscular block and extubation of the trachea, she developed recurrent upper airway obstruction and stridor, necessitating a permanent tracheostomy. The possibility of vagal nerve involvement or injury should always be considered during excision of neck lumps. Preoperative indirect, atraumatic laryngoscopy by experienced surgeons is essential, as are tracheal intubation and vigilant postoperative observation.

Prediction of malignant transformation in oral epithelial lesions by image cytometry.

The value of image analysis in predicting the malignant potential of oral epithelial lesions showing either hyperplasia or dysplasia was investigated; 5-micron formalin-fixed sections of 16 oral epithelial lesions, of which eight had later transformed to carcinoma and eight had not transformed during a follow-up of 10-15 years were studied. The sections were stained with the azure A-Feulgen reaction for nuclear DNA. In each section 200 nuclei of epithelial cells and 20 nuclei of lymphocytes were assessed; all measurements were made blindly. For each nucleus six features related to shape and amount of stain and six features related to chromatin pattern were assessed. For each feature the mean, SD, and interquartile range were determined and used for linear stepwise discriminant analysis. A model of three variables with the most discriminating power was developed. When the jackknifed classification test was applied using this model, the malignant potential of the lesions that later transformed could be predicted with 87.5% accuracy.

Nuclear DNA analysis of oral hyperplasia and dysplasia using image cytometry.

We investigated the value of image analysis in discriminating among oral white lesions with hyperplasia without dysplasia and oral white or white-and-red lesions with moderate or severe dysplasia. Normal oral epithelial tissue was used as a control. Image analysis was applied to 5-micron formalin-fixed sections stained with the azure A-Feulgen reaction for nuclear DNA. For 150-200 cells from each section, 5 nuclear variables were assessed: area, form factor, total stain, average stain and ellipticity. For each variable, 2 measurements were obtained, the mean and the interquartile range, and were used for stepwise discriminant analysis. Using this test, a model of 3 measurements with the most discriminating power was developed. When the jackknife classification test was applied to this model, we could discriminate with 81% accuracy between the 4 groups of tissue studied.

Utility of 2,3-dichloro-5,6-dicyano-p-benzoquinone in assay of codeine, emetine and pilocarpine.

A simple and sensitive spectrophotometric method for the assay of codeine, emetine and pilocarpine is described, based on the interaction of these drugs (as n-electron donors) with 2,3-dichloro-5,6-dicyano-p-benzoquinone (as pi -acceptor) to give a highly coloured radical anion which exhibits maximum absorption at 460 nm. Formation of the radical anion has been established by electron spin resonance measurements. Beer's law is obeyed for the alkaloids investigated. The assay results are in accord with pharmacopoeial assay results. The procedure is sufficiently sensitive to permit unit dose assay of the individual alkaloids in pharmaceutical formulations.