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Over decades, nanozyme has served as a better replacement of bioenzymes and fulfills most of the shortcomings and intrinsic disadvantages of bioenzymes. Recently, manganese-based nanomaterials have been highly noticed for redox-modulated multienzyme mimicking activity and wide applications in biosensing and biomedical science. The redox-modulated multienzyme mimicking activity was highly in tune with their size, surface functionalization, and charge on the surface and phases. On the subject of calcination temperature to Mn3O4nanoparticles (NPs), its phase has been transformed to Mn2O3NPs and Mn5O8NPs upon different calcination temperatures. Assigning precise structure–property connections is made easier by preparing the various manganese oxides in a single step. The present study has focused on the variation of multienzyme mimicking activity with different phases of Mn3O4NPs, so that they can be equipped for multifunctional activity with greater potential. Herein, spherical Mn3O4NPs have been synthesized via a one-step coprecipitation method, and other phases are obtained by direct calcination. The calcination temperature varies to 100, 200, 400, and 600 °C and the corresponding manganese oxide NPs are named M-100, M-200, M-400, and M-600, respectively. The phase transformation and crystalline structure are evaluated by powder X-ray diffraction and selected-area electron diffraction analysis. The different surface morphologies are easily navigated by Fourier transform infrared, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy analysis. Fortunately, for the mixed valence state of Mn3O4NPs, all phases of manganese oxide NPs showed multienzyme mimicking activity including superoxide dismutase (SOD), catalase, oxidase (OD), and peroxidase; therefore, it offers a synergistic antioxidant ability to overexpose reactive oxygen species. Mn3O4NPs exhibited good SOD-like enzyme activity, which allowed it to effectively remove the active oxygen (O2•–) from cigarette smoke. A sensitive colorimetric sensor with a low detection limit and a promising linear range has been designed to detect two isomeric phenolic pollutants, hydroquinone (H2Q) and catechol (CA), by utilizing optimized OD activity. The current probe has outstanding sensitivity and selectivity as well as the ability to visually detect two isomers with the unaided eye.

Purpose: This article seeks to propose a defined set of Sharīʿah standards and guidelines for the charity account in order to provide clear guidance to Islamic financial institutions (IFIs) and eventually create a standardised practice in the management of the charity account by IFIs worldwide. Design/methodology/approach: This article is based on a literature review regarding the origin and concept of the charity account for IFIs. It makes reference to various primary Sharīʿah sources and contemporary Sharīʿah standards pertaining to impermissible income as it relates to the charity account. It also analyses secondary sources of reference, in particular research papers and case studies on the same subject matter. Findings: This article proposes relevant Sharīʿah standards required for the better functioning and standardisation of the charity account application by IFIs. Research limitations/implications: This article will help IFIs, standard-setting bodies and regulators to develop a defined charity account framework. It also addresses the gaps discussed in past research and case studies that have not been resolved to date, particularly on the determination and management of charity accounts at the level of IFIs. Practical implications: The charity account will be better controlled and thus eliminating potential reputational issues arising from collecting and disbursing commitment to donate amounts (CDA). Social implications: The charity account distribution will be better managed and thus of more benefit to the society and recipients. Originality/value: This article promotes the idea of standardisation in the practices of charity accounts, especially in terms of sources and disbursement.

Bacterial endophytes were isolated from the leaves of Bougainvillea spectabilisWilld. and screened for their in vitro antagonistic activity against three important phytopathogenic fungi viz., Neocosmospora keratoplastica, Stemphylium vesicariumand Rhizoctonia solani. Among the 36 endophytic bacterial isolates screened, three isolates designated as BEB1, BEB5 and BEB6 inhibited the mycelial growth of all the three plant pathogenic fungi tested and recorded more than 10% growth inhibition. Scanning electron microscopic observations of hyphae of the pathogenic fungi at the periphery of the inhibition zone in the dual culture plate revealed morphological abnormalities such as shrinkage, pit formation and loss of turgidity. These isolates were identified as Bacillus subtilis(BEB1) and Bacillus cereus(BEB5 and BEB6) based on the MALDI Biotyper analysis. The Bacillus subtilisstrain BEB1, which exhibited the highest level of antagonism, was tested for its sensitivity to cyanide and potential to degrade NaCN. The results revealed that this strain was capable of growing in a medium containing 5 mM of NaCN with a degradation efficiency of 53.8%. This endophyte is valuable for exploitation as a biocontrol agent to control diseases especially in the cyanogenic plants and bioremediation of cyanide from the industrial effluent.

Here, spherical Mn2O3nanozymes were synthesized via a one-step green method using different green precursors, and their physicochemical properties and biological activities were monitored with various green precursors. Powder X-ray diffraction (PXRD) was performed to determine the crystalline properties and phases involved in the formation of cubic Mn2O3nanozymes. The synthesized nanozymes were spherical and examined by SEM and FESEM studies. All of the samples synthesized using different green precursors exhibited different sizes but similar spherical shapes. Moreover, all green-synthesized nanozymes catalyzed the oxidation reaction of the chromogenic substrate 3,3′5,5′ tetramethylbenzidine (TMB) in the absence of H2O2, and A2 (lemon-mediated Mn2O3nanozymes), which the followed Michaelis–Menten kinetics, showed the best activity. Therefore, A2 (lemon-mediated nanozyme) showed oxidase-mimicking activity with distinct Kmand Vmaxvalues calculated by the Lineweaver–Burk plot. Furthermore, the current nanozymes demonstrated a significant ability to kill both Gram-negative and Gram-positive bacteria as well as effectively destroy biofilms under physiological conditions. Moreover, the green-mediated nanozymes also displayed ROS-scavenging activity. Our nanozymes exhibited scavenging activity toward OH and O2–•radicals and metal chelation activity, which were investigated colorimetrically. Therefore, these nanozymes might be used as effective antibacterial agents and also for the consumption of reactive oxygen species.

Ionic liquids (ILs) play an important role in modifying the conformational stability of proteins. The alternation of protein conformation is connected with the accumulation of ILs around the amino acid (AA) side chains and the nature of interactions between them. To understand the nature of the interactions between them, we focused on the physicochemical, spectroscopic, and computational investigation of two essential AAs, namely, l-valine and l-leucine, in the aqueous medium of an IL within the range of molality of the IL (0.001, 0.003, and 0.005 mol kg–1) at three different temperatures (298.15, 303.15, and 308.15 K). Thermodynamic parameters are crucial to understanding the intermolecular interaction that is happening in a solution medium. Experimental data of apparent molar volume (ϕv), limiting partial molar volume (ϕv0), limiting partial molar volume of transfer (Δϕv0), viscosity B-coefficient, limiting molar refraction (RM0), molar conductance, and surface tension indicating that the solute–solvent interaction is happening here, and the extent of solute–solvent interaction is found to be much greater for the l-leucine system compared to the l-valine system. The experimental values of Hepler’s constant (∂ϕE0/∂T) and the temperature derivative of B-coefficient (dB/dT) indicate the structure-breaking nature of the AA in the aqueous solution of [EMIM][PF6]. Free activation energy of the solvent and solute (Δμ10≠and Δμ20≠) showed that the transition state is favorable when the temperature is low and the molality of the AA is low. UV–visible absorbance of the AA was recorded by varying the molality of l-valine and l-leucine, and the association constant is calculated. The main motive of this study is to understand the ability of essential AAs to interact with an aqueous solution of a biologically active IL which may be helpful for the pharmaceutical industry. These findings are likely to provide valuable fundamental information toward understanding the effects of ILs on protein conformational stability.

A biosensor comprising crystalline CuS nanoparticles (NPs) was synthesized via a one-step simple coprecipitation route without involvement of a surfactant. The powder X-ray diffraction method has been used to evaluate the crystalline nature and different phases consist of the formation of CuS NPs. Mainly hexagonal unit cells consist of the formation of CuS NP unit cells. Most of the surfaces are covered with rhombohedral microparticles with a smooth exterior and surface clustering, examined by SEM images, and the shape of NPs was spherical, having an average size of 23 nm, as confirmed by TEM analysis. This study has focused on the peroxidase-mimicking activity, superoxide dismutase (SOD)-mimicking activity, and chemosensor-based colorimetric determination and detection of epinephrine (EP) neurotransmitters with excellent selectivity. The CuS NPs catalyzed the oxidation of the oxidase substrate 3, 3-5, 5 tetramethyl benzidine (TMB) with the help of supplementary H2O2that followed Michaelis–Menten kinetics with excellent Kmand Vmaxvalues calculated by the Lineweaver–Burk plot. Taking advantage of the drop in absorbance upon introduction of EP for the CuS NPs-TMB/H2O2system, a colorimetric route has been developed for selective and real-time detection of EP. The sensitivity of the new colorimetric probe was vibrant, having a linear range of 0–16 μM, and achieved a low limit of detection of 457 nM. Moreover, the present nanosystem exhibited appreciable SOD-mimicking activity which could effectively remove O2•–from commercial cigarette smoke, along with it acting as a potential radical scavenger as well. The new nanosystem effectively scavenged •OH, O2.–, and metal chelation which were investigated calorimetrically.

AbstractNowadays, due to the high development and good quality of education in Turkey the number of international students from different countries is increasing from year to year, despite the different challenges of being in a foreign environment away from their home countries. The purpose of this paper was to investigate challenges faced by international students who study at Sakarya University in Turkey. A phenomenological model was used for this study. The data were collected using the qualitative research method. A semi-structured interview was conducted with the sample, which comprised thirty seven international students from different countries who study at Sakarya University. The response frequencies were analysed. The results show that many responses accepted to have challenges in communication, at the language center, accommodation, the environment, cultural issues, health, and social interaction activities, and that there should be an increased focus on minimizing all the challenges facing them with long and short-term strategies.

Human action recognition in videos is a prominent field in image processing research and it is a frequently required technique for many computer vision applications. In this paper, a new novel algorithm for human action recognition is presented. This algorithm depends on aligned motion images (AMIs). Three types of AMIs are used: aligned motion history image (AMHI), aligned motion energy image (AMEI), and aligned gait energy image (AGEI). As a feature, these AMIs are obtained after frame processing, AMI computing, and AMI processing. In order to classify and identify the activity, structure similarity measurement index is applied for first time in human recognition in this paper. The achieved experimental results demonstrate a high level of accuracy and efficiency. These results are very close to the recognition of the human observer since accomplished result is approximately 98.93% by using the AGEI that calculated from a sub sequence of first 33 frames in each video samples.

This study was conducted to produce a new biodegradable film from easily available and low-cost raw materials by casting method. Corn starch and date pits powder (DPP) in the proportions of 100:0, 90:10, 80:20, 70:30, and 60:40% (w/w) were used. Physical, mechanical, barrier, morphological and antioxidant properties of the developed films were evaluated. The incorporation of DPP increased the thickness, tensile strength, Young's modulus, phenolic compounds, and antioxidant activity of the films, but decreased their swelling index, water solubility, water vapor permeability and elongation capacity. An increase in DPP content decreased the L* values and increased the a*, b*, and ΔE values of the films. SEM images showed that the addition of DPP up to 30% improved the morphological properties of the films. All the developed films were totally biodegradable. This study revealed the potential use of DPP with corn starch for composite biodegradable films formulation.

More than a hundred years ago a group of eight naturalists, two Indians and six Europeans, formed the Bombay Natural History Society, which has flourished ever since. Its history, here told by its eminent president, reflects the historical development of the subject itself – collection of specimens, their description, the foundation of a learned journal, the publication of surveys and the promotion of a wildlife protection law first in Bombay and now enforceable all over India. The present activities of the society embrace educational and research activities.