Synthesis and Characterization of the Mixed Metal Oxide of ZnO-TiO2 Decorated by Polyaniline as a Protective Film for Acidic Steel Corrosion: Experimental,and Computational Inspections

In this work, the preparation, characterization, and evaluation of a novel nanocomposite using polyaniline (PANi) functionalized bi-metal oxide ZnO-TiO₂ (ZnTiO@PANi) as shielding film for carbon steel (CS)-alloy in acidic chloride solution at 298 K was studied. Different spectroscopic characterization techniques, such as UV-visible spectroscopy, dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) approaches, as well as other physicochemical methods, such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and field emission scanning electron microscope (FESEM), were used to describe the produced nanocomposites. The significance of these films lies in the ZnO-TiO₂ nanoparticle’s functionalization by polyaniline, a material with high conductivity and electrochemical stability in acidic solutions. The mechanistic findings of the corrosion inhibition method were obtained by the use of electrochemical methods including open-circuit potentials (OCP) vs. time, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The results indicate that the synthesized ZnTiO@PANi is a powerful acidic corrosion inhibitor, and its inhibition effectiveness is 98.86% in the presence of 100 ppm. Additionally, the charge transfer resistance (R_p) value augmented from 51.8 to 432.7, and 963.7 Ω cm² when the dose of PANi, and ZnTiO@PANi reached 100 ppm, respectively. The improvement in R_p and inhibition capacity values with an increase in nanocomposite dose is produced by the nanocomposite additives covering a larger portion of the surface, resulting in a decrease in alloy corrosion. By identifying the probable regions for molecule adsorption on the steel substrate, theoretical and computational studies provided significant details regarding the corrosion mitigation mechanism. The possibility of substituting old poisonous small substances with inexpensive and non-hazardous polymeric materials as shielding layers for utilization in the oilfield sectors is an important suggestion made by this research.     

Threshold Amsler grid testing in maculopathies

The Amsler grid is a suprathreshold target and thus may fail to detect relative scotomas. If the grid is viewed through two cross-polarizing filters creating low luminance conditions (threshold Amsler grid testing) the test is far more sensitive. Ten patients with disorders of the macula with normal standard white Amsler grid testing were studied with three other Amsler grid tests. Of the 15 involved eyes, 12 had visual field defects present with threshold Amsler grid testing. Tangent screen examination showed defects in 10 of these 12 eyes. The two red grids used were not as sensitive as the threshold grid. Three eyes had metamorphopsia with the white grid which became the site of a visual field defect with threshold testing. Threshold Amsler grid testing is a rapid and sensitive technique for the evaluation of the central 10 degrees of visual field in patients with maculopathies.     

Willingness to Pay for Preventive Dental Care Amongst Older Adults

ObjectiveThe aims of this study were (1) to investigate willingness to pay (WTP) for preventive and curative dental care procedures and (2) to determine the factors that influence older adults’ WTP for dental care.MethodologyOlder, independently living adults from Singapore aged 60 years and older and eligible for government-subsidised dental care were nonrandomly recruited for this study. Data were collected using questionnaires and a clinical examination which recorded details of caries experience, number and distribution of posterior occluding contacts, prosthodontic status, and periodontal status. Using a contingent valuation method, participants were asked to rate WTP in Singapore dollars [SGD$] for 4 aspects of care: dental fillings, dental scaling, dental extraction, and disease prevention advice. Negative binomial regression was used to assess the relationship between the predictor variables associated with WTP for dental fillings, scaling, extraction, and preventive advice.ResultsThe mean value of WTP for a dental filling was SGD$30.23 (SGD$31.05), for scaling was SGD$30.28 (SGD$29.46), for dental extraction was SGD$35.08 (SGD$58.54). In a multivariate model, factors associated with higher WTPfees were as follows: (1) dental filling: age (younger), level of education (higher), and frequency of dental visits (regular); (2) scaling: level of education (higher), agree that dental problems affect overall health, and frequency of dental visits (regular); (3) dental extractions: age (younger), level of education (higher), frequency of dental visits (regular), and prosthodontic status (not wearing); (4) preventive advice: age (younger), gender (male), ethnicity (Chinese), level of education (higher), marital status (married), self-perceived oral health (good), and dental visits (regular).ConclusionsThe findings of our study suggest that older adults are willing to pay most for extraction and least for preventive advice.Key words: Geriatric, Oral health, Health economics, Health attitudes     

Clinical and serum lipid findings in a large family with autosomal dominant retinitis pigmentosa

Retinitis pigmentosa, of unknown cause, has recently been associated with decreased amounts of the polyunsaturated fatty acid, docosahexaenoic acid, in the plasma of affected as compared with unaffected relatives. It has been suggested that this finding may serve as a marker for the disease and might indicate alterations in photoreceptor cell metabolism. The authors studied 54 members of a family with dominantly inherited retinitis pigmentosa in five generations. In addition to the typical clinical findings of retinitis pigmentosa, eight persons also had a bull's eye maculopathy, and four persons had uni- or bilateral optic nerve drusen. When the authors determined the plasma fatty acid and lipid contents, they saw the expected age-related effect on cholesterol and triglycerides, but an unexpected, significant reduction in fatty acids in the unaffected controls as compared with persons with retinitis pigmentosa. The authors' results emphasize the heterogeneity of phenotypic expression of retinitis pigmentosa within a single family.     

Pregnenolone and its sulphate modulate GABAA-receptor-mediated contractile responses in the guinea-pig isolated ileum

Pregnenolone and its sulphate had concentration-dependent dual actions on gamma-aminobutyric acid (GABAA)-receptor-mediated ileal contractile responses, enhancing at 0.001-1 microM but inhibiting at 10 microM. There was a sinistral shift of the GABA dose-response curve in the presence of 0.01 microM pregnenolone, with a significant potentiation over the lower concentration range of GABA (3-30 microM), whilst 10 microM pregnenolone depressed the curve by 50% without a significant change in the EC50, in a manner resembling non-competitive inhibition with picrotoxin. Pregnenolone and its sulphate evidently have modulatory actions at ileal GABAA-receptor complexes in keeping with those seen using neurochemical studies in the central nervous system.