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Radiologists confront formidable challenges when confronted with the intricate task of classifying brain tumors through the analysis of MRI images. Our forthcoming manuscript introduces an innovative and highly effective methodology that capitalizes on the capabilities of Least Squares Support Vector Machines (LS-SVM) in tandem with the rich insights drawn from Multi-Scale Morphological Texture Features (MMTF) extracted from T1-weighted MR images. Our methodology underwent meticulous evaluation on a substantial dataset encompassing 139 cases, consisting of 119 cases of aberrant tumors and 20 cases of normal brain images. The outcomes we achieved are nothing short of extraordinary. Our LS-SVM-based approach vastly outperforms competing classifiers, demonstrating its dominance with an exceptional accuracy rate of 98.97%. This represents a substantial 3.97% improvement over alternative methods, accompanied by a notable 2.48% enhancement in Sensitivity and a substantial 10% increase in Specificity. These results conclusively surpass the performance of traditional classifiers such as Support Vector Machines (SVM), Radial Basis Function (RBF), and Artificial Neural Networks (ANN) in terms of classification accuracy. The outstanding performance of our model in the realm of brain tumor diagnosis signifies a substantial leap forward in the field, holding the promise of delivering more precise and dependable tools for radiologists and healthcare professionals in their pivotal role of identifying and classifying brain tumors using MRI imaging techniques.

The diagnosis of brain tumors at an early stage is an exigent task for radiologists. Untreated patients rarely survive more than six months. It is a potential cause of mortality that can occur very quickly. Because of this, the early and effective diagnosis of brain tumors requires the use of an automated method. This study aims at the early detection of brain tumors using brain magnetic resonance imaging (MRI) data and efficient learning paradigms. In visual feature extraction, convolutional neural networks (CNN) have achieved significant breakthroughs. The study involves features extraction by deep convolutional layers for the efficient classification of brain tumor victims from the normal group. The deep convolutional neural network was implemented to extract features that represent the image more comprehensively for model training. Using deep convolutional features helps to increase the precision of tumor and non-tumor patient classifications. In this paper, we experimented with five machine learnings (ML) to heighten the understanding and enhance the scope and significance of brain tumor classification. Further, we proposed an ensemble of three high-performing individual ML models, namely Extreme Gradient Boosting, Ada-Boost, and Random Forest (XG-Ada-RF), to derive binary class classification output for detecting brain tumors in images. The proposed voting classifier, along with convoluted features, produced results that showed the highest accuracy of 95.9% for tumor and 94.9% for normal. Compared to individual methods, the proposed ensemble approach demonstrated improved accuracy and outperformed the individual methods.

Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H2O2) and pH conditions were evaluated. The λmax of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a significant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no influence on degradation efficiency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.

Aqueous pollution due to textile industry is an important issue. Photocatalysis is one of the methods used for eradication of dyes from textile industrial effluents. In this study, the synthesis, characterization and evaluation of photo catalytic activity of Ag-TiO2 is reported. TiO2 catalysts with 2, 4, 6 and 8% loading of Ag were prepared by green methods using Azadirachta indica leaves extract as reducing agent with titanium dioxide and silver nitrate as precursor materials. Prepared catalyst was characterized by advanced techniques and was used as catalyst for degradation of Methylene blue and Rhodamine B dyes. Deposition of Ag greatly enhanced the catalytic efficiency of TiO2 towards degradation of dyes. Irradiation of catalyst excites electrons from conduction band of catalyst to valence band yielding an electron-hole pair. This electron-hole pair undergoes secondary reactions and produce OH∙ radicals. These active radicals take part in degradation of dyes. More than 90% dyes were degraded in 120 min. Photo catalytic degradation of Methylene blue and Rhodamine B followed Eley-Rideal mechanism which states that dye react in fluid phase with adsorbed oxygen.

The present study investigates a comparative study of the sorption of Cr3+ and Cr6+ from water using an agricultural by-product; mango peels in batch system under the effect of initial metal ion concentrations, solution pH, temperature, sorbent dose and contact time. Characterization of the mango peels was done before and after sorption of Cr3+ and Cr6+ using scanning electron microscopy, surface area pore size analyzer and FTIR spectroscopy. The pH study revealed that that maximum removal of Cr3+ and Cr6+ was obtained at pH 5.0 and 7.0 respectively. Among various kinetic models, pseudo-2nd order well explained the data owing to the higher values of R2 and the nearness between the values of experimental and calculated sorption capacities. The isotherms study revealed that Freundlich is the suitable isotherm for explanation of the equilibrium data due to higher R2 values. The monolayer sorption capacity of mango peels was found to be 98.039 mg g-1 for Cr3+ and 66.666 mg g-1 for Cr6+. The spontaneity and exothermic nature of the sorption process of Cr3+ and Cr6+ using mango peels was reflected from thermodynamic study.

In this study, gamma/H2O2 and UV/H2O2 treatment procedures were used for the degradation of five dyes including reactive red PB (R-24), reactive orange P3LN (O-13), reactive turquoise blue PG (B-21), reactive golden yellow H2R (O-12) and reactive lemon yellow C4G L (Y-15). The dye samples of 50 or 100 ppm concentration were treated with either gamma (0–10 kGy) or UV radiations in the presence/absence of H2O2. This treatment resulted in the elimination of chromophoric groups and degradation of dye molecule into low molecular weight fragments. The H2O2 treatment caused the generation of hydroxyl radicals which degraded the pollutants non-selectively by means of chain oxidation process. The treatment effectiveness was increased when H2O2, which was used in conjunction with UV or gamma radiation and the treated water quality, improved significantly. However, the gamma/H2O2 treatment was found to be the more effective and efficient method as compared to the UV/H2O2 treatment for the removal of dyes from the water. [ABSTRACT FROM AUTHOR]

The development of semiconductor photocatalysts has recently witnessed notable momentum in the photocatalytic degradation of organic pollutants. ZnO is one of the most widely used photocatalysts; however, its activity is limited by the inefficient absorption of visible light and the fast electron–hole recombination. The incorporation of another metal or semiconductor with ZnO boosts its performance. In this present study, a heterostructured ZnO-Bi2O3 composite was synthesized via a simple co-precipitation method and was investigated for the UV-driven photocatalytic degradation of the Reactive Orange 16 (RO16), a model textile dye. The successful fabrication of ZnO-Bi2O3 microstructures with crystalline nature was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX). The discoloration of the dye solution was quantified using UV–Vis spectroscopy to determine the photocatalytic efficiency. The photocatalytic activity results demonstrated that the photodegradation at ZnO-Bi2O3 heterojunction was more efficient and 300 and 33% faster than individual Bi2O3 and ZnO catalysts, respectively, an effect that is indicative of a synergistic effect. In the presence of ZnO-Bi2O3 particles, the UV light-driven activity for RO16 degradation was twice as high as in its absence. The influence of adding the oxidant H2O2 on the UV-induced photocatalytic degradation was investigated and the results revealed a two-time increase in the photocatalytic activity of ZnO-Bi2O3 compared to UV irradiation alone, which could be ascribed to a summative degradative effect between UV and H2O2. Hence, this approach holds the potential for environmentally friendly wastewater treatment. [ABSTRACT FROM AUTHOR]

Chlorophenols are compounds with high toxicity, poor biodegradability, and carcinogenic and recalcitrant properties. This work studies, for the first time, the destruction and detoxification of 2-chlorophenol (2-CP) in water using 60Co gamma radiation under different conditions including varied radiation doses, addition of hydrogen peroxide (H2O2), and varied pH values. High-performance liquid chromatography (HPLC) and ion chromatography (IC) confirmed a successful degradation of 2-CP to primarily yield phenol molecules and chloride anions. A radiation dose as low as 25 kGy achieved approximately 90% removal of 50–150 ppm of 2-CP in neutral water. However, the addition of a strong oxidizer such as H2O2 to 2-CP solutions reduced the required dose to achieve 90% removal to at least 1.3-fold. The reduction in radiation doses was also observed in acidic and alkaline media, reducing the required doses of 90% removal to at least 0.4-fold. It was imperative to study the toxicity levels of the oxidation by-products to provide directions for the potential applicability of this technology in water treatment. Toxicology Microtox® bioassay indicated a significant reduction in the toxicity of the degradation by-products and the detoxification was further enhanced by the addition of H2O2 and changing the pH to more acidic or alkaline conditions. These findings will contribute to the knowledge of the removal and detoxification of such challenging environmental contaminant and could be potentially applied to other biologically resistant compounds.

Nowadays, cobalt containing cathodes are widely used in solid oxide fuel cells (SOFCs) due to their high performance. There are many disadvantages of cobalt based cathodes such as reduction, high cost and evaporation of cobalt. In order to reduce these detrimental effects, cobalt free composites such as La0.54Sr0.46Zn0.20Fe0.80O3−δ (LaSrZnFeO1) La0.80Sr0.20Zn0.20Fe0.80O3−δ (LaSrZnFeO2), and La0.80Sr0.20Zn0.40Fe0.60O3−δ (LaSrZnFeO3) have been prepared by the sol–gel technique. The electrical properties and microstructure of the proposed cathode materials were investigated in this study. The characterization of the prepared materials was carried out by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The thermal stability of the synthesized materials was observed with thermogravimetric analysis (TGA). The highest DC conductivity of LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 cathodes achieved was 8.12, 7.12 and 6.62 S cm−1 at 600 °C, respectively. The single cell achieved maximum power densities of 436, 370 and 296 mW cm−2 with LaSrZnFeO1, LaSrZnFeO2, and LaSrZnFeO3 cathodes at 600 °C, respectively. The better current densities of 1472, 1422 and 1397 mA cm−2 for LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 were attained at 600 °C, respectively. The SEM images disclosed that the prepared nanocomposite cathodes were porous and homogeneous. The purity of the prepared samples was confirmed by XRD. The proposed LaSrZnFeO1, LaSrZnFeO2 and LaSrZnFeO3 cathodes achieved a maximum OCV of 0.90, 0.83 and 0.76 volts at 600 °C, respectively. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) have emerged as a promising approach for the removal of organic dyes from effluents. Different AOPs were employed for the degradation of Reactive Yellow 160A (RY-160A) dye, i.e., SnO2/UV/H2O2 and TiO2/UV/H2O2. In the case of UV treatment, maximum degradation of 28% was observed, while UV/H2O2 furnished 77.78% degradation, and UV/H2O2/TiO2 degraded the RY-160A dye up to 90.40% (RY-160A 30 mg/L, 0.8 mL of H2O2). The dye degradation was 82.66% in the case of UV/H2O2/SnO2 at pH 3. FTIR and LC-MS analyses were performed in order to monitor the degradation by-products. The cytotoxicity and mutagenicity of RY-160A dye were evaluated by hemolytic and Ames (TA98 and TA100 strains) assays. It was observed that the RY-160A dye solution was toxic before treatment, and toxicity was reduced significantly after treatment. Results indicated that UV/H2O2/TiO2 is more efficient at degrading RY-160A versus other AOPs, which have potential application for the remediation of dyes in textile effluents. [ABSTRACT FROM AUTHOR]

The synthesis of efficient photocatalysts for visible light-assisted photodegradation of aqueous phase organic pollutants has received significant consideration recently. In this research, Co-doped ZnO is synthesized by the precipitation method for enhanced visible-light assisted photodegradation of methylene blue. The XRD and XPS analyses showed that Co exists in a divalent state in the as-prepared composite. The UV-visible DRS analyses showed that incorporation of Co2+ in the ZnO structure greatly enhanced the visible light absorption due to its photosensitizing effect. Analyses of reaction mixtures showed about 9, 64, 96, and 79% degradation of methylene blue in the presence of pure ZnO, 5% CoO–ZnO, 10% CoO–ZnO, and 15% CoO–ZnO, respectively. The photodegradation of methylene blue is described using the Langmuir–Hinshelwood mechanism. [ABSTRACT FROM AUTHOR]

The PMMA/PVC/ZnO-nanocomposites with zinc oxide nanoparticle (particle size < 50nm) was synthesized by solution casting technique. Morphology of the synthesized nano composites have been investigated by FT-IR and XRD techniques. After characterization, synthesized composites were applied for antibacterial, selective antibiofilm and free radical scavenging screening. Antibacterial studies were measured against different bacterial strains. Antibiofilms activities were studied against those bacterial model pathogenic strains which showed highest and minimum sensitivity as a (~94 and ~88 at 160 µg/ml). Antioxidant activity of synthesized nanocomposites were measured by DPPH and showed scavenging capacity with IC50, 110 to > 200 µg/mL. Thus PMMA/PVC/ZnO nanocomposite showed promising antimicrobial activity and antioxidant activity that can be used for biomedical applications. [ABSTRACT FROM AUTHOR]