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The present paper describes the design of shape-oriented hydrogel nanospheres using a facile ultrasonication-supported crosslinked copolymerization technique. The effect of variable monomer concentration on the homogeneity of hydrogel nanospheres was investigated. The chitosan-cl-poly(MMA) hydrogel nanospheres were well characterized using various techniques such as FTIR, XRD, TGA, SEM, and TEM. The chitosan-cl-poly(MMA) hydrogel nanospheres were studied for their swelling behavior and could potentially be used as a novel adsorbent for rhodamine B dye remediation from aqueous media. The study found that utilizing chitosan-cl-poly(MMA) nanohydrogel spheres at the optimal pH 5 increased RhB dye adsorption capacity from 7.9 to 17.8 mg/g (pH 2 to 5), followed by a slight reduction. Furthermore, when nanohydrogel concentration increased, adsorption capacity dropped from 18.03 to 2.8 mg/g, but adsorption percentage climbed from 90.2% to 97.8%. At an initial dye concentration of 140 mg/L, rhodamine B adsorption achieved 204.3 mg/g in 60 min. The rhodamine B dye adsorption study includes adsorption kinetics, isotherm, and thermodynamics analyses. The interpretation of the adsorption study revealed that Langmuir isotherms fit best with a qmax value of 276.26 mg/g, which is in close approximation with the experimental value, whereas pseudo-second-order kinetics explains the adsorption process rate. The interaction of RhB dye with chitosan-cl-poly(MMA) hydrogel nanospheres involves multiple forces such as electrostatic interactions, hydrogen bonding, van der Waals forces, etc. [ABSTRACT FROM AUTHOR]

Reliability of high demand machines is quite necessary and it can be maintained through proper and timely maintenance, Ultralow temperature (ULT) freezer is one of those kinds of machines which are in high demand during covid-19 pandemic for the storage of vaccine. The rapid production of vaccines for the prevention of coronavirus disease 2019 (COVID-19) is a worldwide requirement. Now the next challenge is to store the vaccine in a ULT freezer. It's become really a big problem to store the vaccine which creates the demand of ULT freezer. The present paper investigates a situational based performance of the ULT freezer with the aim to predict the impact of different component failures as well as human errors on the final performance of the same. For the study, it is not possible to extract the parameters (failure rate and repair time) of the components that never failed before. Thus, to overcome this difficulty, here authors use the possibility theory. Authors present the available data in Right triangular fuzzy number with some tolerance as suggested by system analyst. The lambda-tau methodology and arithmetic operations on right triangular generalized fuzzy numbers (RTrFN) are used to find the various performance parameters namely MTTF, MTTR, MTBF, reliability, availability, maintainability (RAM) and ENOF, under fuzzy environment. The proposed model has been studied using possibility theory under working conditions, preventive maintenance as well as under the rest of conditions. This study reveals the most and least critical component of the ULT freezer which helps maintenance department to plan the maintenance strategy accordingly. [ABSTRACT FROM AUTHOR]

Antibiotic water contamination is a growing environmental problem in the present day. As a result, water treatment is required for its reduction and elimination. Due to their important role in resolving this issue, photocatalysts have drawn a great deal of interest over the past few decades. When non-biodegradable organic matter is present in polluted water, the photo catalytic process, which is both environmentally friendly and an improved oxidation method, can be an effective means of remediation. In this regard, we report the successful synthesis of pure phased rare earth doped ZnO nanoparticles for tetracycline degradation. The prepared catalysts were systematically characterized for structural, optical, and magnetic properties. The optical band gap was tailored by rare earth doping, with redshift for Sm and Dy doped nanoparticles and blueshift for Nd doped ZnO nanoparticles. The analysis of photoluminescence spectra revealed information about the defect chemistry of all synthesised nanoparticles. Magnetic studies revealed that all synthesized diluted magnetic semiconductors exhibit room temperature ferromagnetism and can be employed for spintronic applications. Moreover, Dy doped ZnO nanoparticles were found to exhibit a maximum degradation efficiency of 74.19% for tetracycline (TCN) removal. The synthesized catalysts were also employed for the degradation of Malachite green (MG), and Crystal violet (CV) dyes. The maximum degradation efficiency achieved was 97.18% for MG and 98% for CV for Dy doped ZnO nanoparticles. The degradation mechanism involved has been discussed in view of the reactive species determined from scavenging experiments. [ABSTRACT FROM AUTHOR]

In this paper, we describe the creation of a moderate band gap Nd-substituted Ni-Zn ferrite as a nano photo catalyst via a simple and cost-effective process of solution combustion. Nd substitution alters the crystallite size, shape, band gap, and magnetic characteristics of Ni-Zn ferrite significantly. Investigations using X-ray diffraction revealed that all samples display a pure phase. The average crystallite size was determined to be between 31.34 and 38.67 nm. On Nd doping, morphology investigations indicated that the shape of nanoparticles changed from approximately spherical to stacked grains. Band gap experiments confirmed the red shift in optical band gap on Nd doping. The synthesized catalysts Ni0.5Zn0.5Fe2O4 (Nd0), Ni0.5Zn0.45Nd0.05Fe2O4 (Nd1), and Ni0.5Zn0.5Nd0.05Fe1.95O4 (Nd2) have been effectively used for the degradation of methylene blue dye under the solar light irradiation. The sample with Nd substitution on Fe sites had the highest methylene blue degradation efficiency. Nd2 photo catalyst degrades the methylene blue dye with a degradation efficiency of 98% in 90 min of solar light irradiation. The photocatalytic activity is triggered by the existence of oxygen vacancies and a mixed valence state of Ni, Fe, and Nd, as confirmed by the XPS investigation. In addition, the investigations on scavenging reveal that the hydroxyl radical is a reactive component in the degradation process. The degradation route has been investigated in relation to the many potential reactions and discovered reactive substances. [ABSTRACT FROM AUTHOR]

Constructing visible-light-active Z-scheme heterojunctions has proven fruitful in enhancing the photocatalytic activity of photocatalysts for superior water clean-up. Herein, we report the fabrication of a CoFe2O4@Bi2O3/NiO (CBN) Z-scheme nanoheterojunction. The obtained CBN heterojunction was used for visible-light-assisted degradation of ofloxacin (OFL) in water. The OFL degradation efficiency achieved by the CBN heterojunction was 95.2% in 90 min with a rate constant of kapp = 0.03316 min−1, which was about eight times that of NiO and thirty times that of CoFe2O4. The photocatalytic activity of a Bi2O3/NiO Z-scheme heterojunction was greatly enhanced by the visible activity and redox mediator effect of the cobalt ferrite co-catalyst. Higher charge-carrier separation, more visible-light capture, and the Z-scheme mechanism in the Z-scheme system were the important reasons for the high performance of CBN. The scavenging experiments suggested ●O2− as an active species for superior OFL degradation. The possible OFL degradation pathway was predicted based on LC-MS findings of degradation intermediate products. The magnetic nature of the CBN helped in the recovery of the catalyst after reuse for six cycles. This work provides new insights into designing oxide-based heterojunctions with high visible-light activity, magnetic character, and high redox capabilities for potential practical applications in environmental treatment. [ABSTRACT FROM AUTHOR]

Authentication, authorization, and data access control are playing major roles in data security and privacy. The proposed model integrated the multi-factor authentication–authorization process with dependable and non-dependable factors and parameters based on providing security for tenants through a hybrid approach of fully homomorphic encryption methodology: the enhanced homomorphic cryptosystem (EHC) and the Brakersky–Gentry–Vaikuntanathan (BGV) scheme. This research was composed of four major elements: the fully homomorphic encryption blended schemes, EHC and BGV; secure token and key implications based on dependable and don-dependable factors; an algorithm for generating the tokens and the suitable keys, depending on the user's role; and the execution of experimental test cases by using the EHC algorithm for key and token generation, based on dependable and non-dependable parameters and time periods. The proposed approach was tested with 152 end-users by integrating six multi-tenants, five head tenants, and two enterprise levels; and achieved a 92 percent success rate. The research integrated 32-bit plain text in the proposed hybrid approach by taking into consideration the encryption time, decryption time, and key generation time of data transmission via cloud servers. The proposed blended model was efficient in preventing data from ciphertext attacks and achieved a high success rate for transmitting data between the multi-tenants, based on the user-role-user type of enterprise cloud servers. [ABSTRACT FROM AUTHOR]

Herein, we report the designing of a C3N4/BiOI heterostructure that is supported on gum acacia-crosslinked-poly(acrylamide) hydrogel to fabricate a novel nanocomposite hydrogel. The potential application of the obtained nanocomposite hydrogel to remediate crystal violet dye (CVD) in an aqueous solution was explored. The structural and functional analysis of the nanocomposite hydrogel was performed by FTIR (Fourier transform infrared spectroscopy), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The different reaction parameters, such as CVD concentration, nanocomposite hydrogel dosage, and working pH, were optimized. The C3N4/BiOI heterostructure of the nanocomposite hydrogel depicts Z-scheme as the potential photocatalytic mechanism for the photodegradation of CVD. The degradation of CVD was also specified in terms of COD and HR-MS analysis was carried to demonstrate the major degradation pathways. [ABSTRACT FROM AUTHOR]

Classical sets are used commonly to consider reliability. Because of the uncertainty in the data (which considered in the present paper) classical sets fail to describe the reliability accurately. Uncertainty leads to fluctuation in the actual situation of the structure. Fuzzy logic method attempts to test system reliability with the benefit of membership function. Within this context, specific problems of reasoning-based approaches are studied, explored and correlated with standard reliability approaches. In this paper Generalized Trapezoidal Fuzzy numbers (GTrFN) are used to assess the structure's fuzzy reliability. The reliability of each event is assigned with different level of satisfaction and some improved operations on the generalized trapezoidal fuzzy numbers (GTrFN) are used to calculate the fuzzy boundaries for the resultant reliability of the final event along with the degree of satisfaction. Also the results are compared to demonstrate the application of the improved operations on Generalized Trapezoidal Fuzzy Numbers (GTrFN). The obtained results converge to more precise interval values as compare to the vague fuzzy number. [ABSTRACT FROM AUTHOR]

This work presents an application of upgraded arithmetic operations on trapezoidal fuzzy number to extend the reliability from point estimation to interval estimation. A realistic example of an accidental case has been taken to show the desired results. As we know that uncertainty is a disregardable phenomenon and in this situation crisp reliability may not be exact. To get a better hold on this situation, we introduce a method of trapezoidal fuzzy number and upgraded arithmetic operations. In this paper, the reliability of each factor is represented by the trapezoidal fuzzy number and the final reliability is obtained in the form of trapezoidal fuzzy number. Hence, the dejection of fuzzy number is preserved and the crisp region is increased to illustrate the highest membership grade as an interval. So it can help the decision maker to analyse the behaviour of the system and take effective decision accordingly to reduce the chance of mishappening. [ABSTRACT FROM AUTHOR]

In this work, the physical properties of nanocrystalline samples of La0.7Sr0.3Mn1−xFexO3 (0.0 ≤ x ≤ 0.20) perovskite manganites synthesized by the reverse micelle (RM) technique were explored in detail. The phase purity, crystal structure, and crystallite size of the samples were determined using X‐ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. All the samples had rhombohedral crystal structure and crystallite size increased with increase in Fe content in La0.7Sr0.3MnO3. The scanning electron micrographs (SEMs) exhibited smooth surface morphology and nonuniform shape of the particles. The optical properties studied using UV‐visible absorption spectroscopy revealed a decrease in the absorbance and optical band gap with an increase in Fe content in La0.7Sr0.3MnO3 compound. The temperature‐dependent resistivity measurements revealed semiconducting nature of x = 0 and 0.1 samples up to the studied temperature range, while a metal‐to‐insulator transition was observed at higher Fe doping. Magnetic studies revealed weak ferromagnetism in all the samples and a reduction in the maximum magnetization with an increase in Fe content. A close correlation between electrical transport and magnetic properties was observed with the doping of Fe ion in La0.7Sr0.3MnO3 at Mn site. These results advocate strong interactions associated with the double exchange mechanism among Fe3+ and Mn3+ ions. [ABSTRACT FROM AUTHOR]

In recent times cost-effective advanced materials with dual applications in photocatalytic water treatment and electrochemical sensing have been explored and developed. Herein we report facile solution combustion synthesis of ZnO/Fe 2 O 3 (ZF) type-II heterojunction for electrochemical sensing of dopamine and visible assisted photocatalytic reduction of carcinogenic Cr(VI) into Cr(III). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to evaluate the compatibility of the electrodes for DA sensing. Furthermore, DPV curves revealed that ZF2 (ZnO: Fe 2 O 3 - 3:0.5) modified GCEs possessed 0.27 μM and 0.7 μM of LOD and LOQ with good linear range from 3 μM to 30 μM. Overall, reproducibility and interference studies confirm the efficient use of material for DA sensing. The junction ZF2 shows best performance with 88% Cr(VI) photo-reduction under visible light in 90 min and 100% reduction with tartaric acid as sacrificial agent (utilizing holes) in just 45 min. The effect of sacrificial agents and scavengers suggest the photogenerated electrons were major active species followed by ●O 2 −. The CB edges have enough potential for rapid reduction of hexavalent chromium under visible light and solar light. The photoluminescence and electrochemical impedance suggest lowered recombination, high charge separation and charge transfer capacity in the heterojunction. The transfer of electrons from conduction band of Fe 2 O 3 to that of ZnO having high enough negative potential to reduce Cr(VI), thus utilizing the CB potential of wide band gap ZnO for rapid visible photocatalysis. In addition shortcomings as low conductivity Fe 2 O 3 and high band gap of ZnO are both minimized in the junction. This study confirmed that popular semiconductors as ZnO and Fe 2 O 3 have enough potential in dual role as electrochemical sensors and visible photocatalysts with best performance by optimizing the conditions and ratios. Image 1 [ABSTRACT FROM AUTHOR]

The present study was carried out in oak (Quercus leucotrichophora) dominated forest of Pauri. Two permanent plots were selected of which one was BPS and other was UBPS. The vegetational data were analysed for both the sites i.e., floristic composition, density, basal cover, A/F, Shannon Wiener index and Simpson's index of dominance (cd). A total of 6-8 trees species and 24-26 shrub species were found on both BPS and UBPS. BPS showed maximum density than UBPS. Contagious pattern of distribution was common. This paper represents a close association among man, fire and forest ecosystem. [ABSTRACT FROM AUTHOR]

In the present work, mixed-spinel ferrite anchored onto graphitic carbon nitride (GCN) was synthesized for mineralization of antibiotic pollutant from waste water. A Z-scheme g-C 3 N 4 /Ni 0.5 Zn 0.5 Fe 2 O 4 nano heterojunction was fabricated by three step procedure: pyrolysis, solution combustion and mechanical grinding followed by annealing. The prepared photocatlyst was tested for degradation of Doxycycline (DC) drug under the natural sun light. Results revealed that the prepared heterojunction has maximum degradation efficiency of 97.10% pollutant in 60 min experiment. The Z-scheme heterojunction between g-C 3 N 4 and Ni–Zn ferrite improves the photoinduced charges separation and protection of redox capability and therby increases the photo degradation efficiency. The scavenging experiments suggested that O 2 −● and h+ as main active species responsible for degradation of the antibiotic. In addition, the dopant variation can drive the shists in band gap and energy band positiong too which makes then excellent candidates for synthesizing tunable heterostructures with organic semiconductors. The work focusses on designing and developing of saimpler but efficient magnetic heterojunctions with superior redox capability for solar powered waste water treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Overlap syndrome in hepatology is emerging as a diagnostic and therapeutic challenge, which is further complicated by the present gaps in the information regarding the immunopathogenesis of these diseases. The present review represents a concise review of literature on overlap syndromes with emphasis on prevalence, etiopathogenesis, clinical presentation, diagnosis, and management of true overlap syndromes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fe doped ZnO nanoparticles have been successfully synthesized by simple sol–gel route. [•] Solubility limit of Fe in ZnO matrix is found to be less than 5%. [•] Fe doped ZnO nanoparticles are better photocatalytic activist than ZnO. [•] Prepared particles possess intrinsic room temperature ferromagnetism. [ABSTRACT FROM AUTHOR]

This work reports synthesis of a dual-function facile heterojunction and investigation of role of the charge transfer dynamism between individual semiconductor components for superior photocatalytic and electrochemical sensing application. The bio-benevolent and sturdy ZnO/Fe 2 O 3 heterojunctions were utilized for visible light facilitated photo-degradation of sulfamethoxazole (SMX) antibiotic and electrochemical sensing of dopamine drug (DA). The fabricated heterojunction were characterized for structural, optical, and magnetic properties. Structural studies revealed the formation of nano heterojunction containing both phases. Magnetic studies confirmed the highly pure magnetic nature of photocatalysts. ZnO/30 wt%Fe 2 O 3 heterojunction (S2) shows 95.2% SMX degradation under visible light and high retention of performance under solar light. The scavenging experiments infer that OH radicals are the active species responsible for degradation. A Z-scheme photocatalytic mechanism was predicted for higher performance with protection of high potential VB of ZnO and CB of Fe 2 O 3 for high generation of reactive oxygen species. LC-MS was employed to predict a plausible degradation route. The sample modified glassy carbon electrodes (GCE) were used for electrochemical sensing of dopamine via cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The S2 junction exhibited 0.18 μM limit of detection with concentration range of 1 μM–50 μM. The stability test was successfully carried out at room temperature for 15 days. In addition, the S2 modified electrodes were spiked in real urine samples and good results were obtained. DPV reveals that S2 modified electrode is best sensor for dopamine sensing among all synthesized heterojunctions. The detection mechanism was also discussed in detail. The in-built metal redox i.e Zn2+/Zn+ and Fe3+/Fe2+ facilitate the Z-scheme transfer, improve the charge transfer capacity and reduce the recombination. This study is beneficial because it reports utilization of popular and well-tested semiconductor metal oxides to form heterojunctions with dual capabilities of environmental detoxification and cost-effective electrochemical detection of biomolecules. [Display omitted] • Dual functional facile ZnO/Fe 2 O 3 Z-scheme heterojunction with in-built metal redox. • Visible light assisted high performance photocatalytic removal of sulfamethoxazole. • OH as active species high potential band protection-Z-scheme • Sensitive and selective dopamine sensing with 0.18 μM limit of detection. [ABSTRACT FROM AUTHOR]

Iron nanoparticles (Fe NPs), monometallic Fe@carbon quantum dots (Fe@CQDs) and bimetallic Fe/Ag@carbon quantum dots (Fe/Ag@CQDs) nanocomposites were prepared by simple co-precipitation/reduction method. The nanoparticles (NPs), monometallic nanocomposite (MNCs) and bimetallic nanocomposite (BMNCs) were characterized using various techniques. The adsorptional/photocatalytic activity of NPs, MNCs, and BMNCs were investigated for the removal of fast green (FG) dye from aqueous medium. The degradation of FG dye under combined adsorptional/photocatalytic condition was efficient. The catalytic nature of synthesized NPs, MNCs and BMNCs was also explored for the oxidation of benzyl alcohol and esterification of acetic acid. For oxidation of benzyl alcohol with H 2 O 2 in the presence of acetonitrile (ratio of butyl alcohol: H 2 O 2 was 2:1) at temperature 80 °C, the Fe NPs gave maximum yield (87%). The esterification of acetic acid with ethyl, isopropyl and butyl alcohol showed that butyl alcohol gave maximum yield of 82%, 80%, and 84% for Fe NPs, Fe@CQDs MNCs and Fe/Ag@CQDs BMNCs, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel nanocomposite Fe0.01Ni0.01Zn0.98O/polyacrylamide was synthesized. [•] FNZP/PAM nanocomposite shows good degradation efficiency for MB and MG. [•] Rapid decolouration of dyes was observed under coupled adsorption and photocatalysis. [•] Dye degradation followed the pseudo first-order kinetics. [•] A higher recycle efficiency and antibacterial activity was achieved for nanocomposite. [Copyright &y& Elsevier]

Background The association between hypothyroidism and iron-deficiency anemia (IDA) in pregnancy is not well established. Hence, this study aimed to investigate the association between hypothyroidism and IDA during the first trimester of pregnancy. Methodology In this study, a total of 144 pregnant women were included. Thyroid-stimulating hormone (TSH), free T4 (FT4), free T3 (FT3), and ferritin were measured. Based on TSH values, pregnant women were divided into the following two groups: euthyroid (n = 74) and hypothyroid (n = 70). Results There was a significant increase in TSH levels and a significant decrease in the levels of FT4, FT3, ferritin, iron, and hemoglobin (Hb) in hypothyroid pregnant women compared to euthyroid pregnant women. The correlation and regression analysis revealed a significant negative association of TSH and a positive association of FT4 with ferritin, iron, and Hb. Conclusions These findings demonstrate the association of hypothyroidism with IDA during the first trimester of pregnancy. Further studies with thyroxine therapy in hypothyroid pregnant women and its impact on IDA will open novel therapeutic approaches in the management of IDA during pregnancy. Further, measurement of serum ferritin during pregnancy may provide valuable information in the diagnosis and management of IDA., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, R et al.)

Background: Sternocostoclavicular joint (SCCJ) swelling is an underdiagnosed, albeit important entity in clinical practice. The present study was conducted in order to identify the incidence and common causes of this entity., Methods: Patients presenting to the Orthopaedic Clinic with a swelling of the sternocostoclavicular joint, during the study period of two years were included, and detailed history was obtained from the patient. Baseline investigations (total and differential leukocyte count, ESR, CRP, X-ray and CT) wereperformed. Magnetic resonance imaging,FNAC or joint aspiration was performed whenever clinically or radiologically indicated., Results: A total of 21 patients were enrolled into the study for a duration of 2 years. Patients mainly presented with both pain and swelling of the SCCJ with predominant right sided involvement. Osteoarthritis was the most frequent diagnosis followed by infections, primary bone/cartilage tumor, and metastasis., Conclusions: Although most of the patients with SCCJ swelling have a benign etiology, it is not wise to dismiss thisswelling as degenerative changes. Serious conditions like septic arthritis or neoplasia, may masquerade with similar presentations such as osteoarthritis. It would be therefore imperative to rule out all of these potentially life threatening conditions using thorough clinic-radiological workups.