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The field of wireless communication has undergone revolutionary changes driven by technological advancements in recent years. Central to this evolution is wireless ad hoc networks, which are characterized by their decentralized nature and have introduced numerous possibilities and challenges for researchers. Moreover, most of the existing Internet of Things (IoT) networks are based on ad hoc networks. This study focuses on the exploration of interference management and Medium Access Control (MAC) schemes. Through statistical derivations and systematic simulations, we evaluate the efficacy of guard zone-based MAC protocols under Rayleigh fading channel conditions. By establishing a link between network parameters, interference patterns, and MAC effectiveness, this work contributes to optimizing network performance. A key aspect of this study is the investigation of optimal guard zone parameters, which are crucial for interference mitigation. The adaptive guard zone scheme demonstrates superior performance compared to the widely recognized Carrier Sense Multiple Access (CSMA) and the system-wide fixed guard zone protocol under fading channel conditions that mimic real-world scenarios. Additionally, simulations reveal the interactions between network variables such as node density, path loss exponent, outage probability, and spreading gain, providing insights into their impact on aggregated interference and guard zone effectiveness.

Alzheimer’s disease (AD) is a neurodegenerative disorder and cholinesterase (ChE) enzymes are considered as crucial targets for the treatment of AD. Herein, a series of heteroaryl substituted imidazole derivatives (5a-5x) was prepared using amino acid catalyzed, one-pot facile synthetic approach. In this context, the catalytic potentials of different amino acids were investigated and 15 mol% of glutamic acid was identified as the most suitable catalyst to obtain the target products in good yields up to 90 %. These structurally exciting heterocyclic hybrids were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. This series displayed moderate to excellent inhibitory potential against AChE with IC50 values > 25 µM and the most active compound was 3-(4-(1-(3,5-dimethylphenyl)-4,5-diphenyl-1H-imidazol-2-yl)-1-phenyl-1H-pyrazol-3-yl)–2H-chromen-2-one (5x) with IC50 value of 25.83 ± 0.25 µM.This inhibitory potential was attributed to hydrophobicity as the major contributory factor. The most potent compound against BChE was 1,3-diphenyl-4-(1,4,5-triphenyl-1H-imidazol-2-yl)-1H-pyrazole (5a) with IC50 value of 0.35 ± 0.02 µM followed by other potent compounds 5p, 5 m, 5x, 5b, 5c, 5e and 5f with IC50 values

Inflammation is the immune system's adaptive response to tissue dysfunction or homeostatic imbalance, inducing fever, pain, physiological and biochemical changes via the cyclooxygenase (COX) and lipoxygenase (LOX) pathways. NSAIDs (non-steroidal anti-inflammatory drugs), such as diclofenac acid and naproxen, are the most common inhibitors of the COX pathway. These drugs, however, are currently being studied as LOX inhibitors as well. Therefore, in the present study, a novel series of diclofenac acid and naproxen-bearing hydrazones 7(a-r) were designed, synthesized, and characterized by different spectroscopic methods like 1H NMR, 13C NMR, IR and HRMS (EI) analysis. All these synthesized compounds were evaluated for their in vitro inhibitory potential against the Soybean 15-lipoxygenase (15-LOX) enzyme. These compounds exhibited varying degrees of inhibitory potential ranging from IC50 4.61 ± 3.21 μM to 193.62 ± 4.68 μM in comparison to standard inhibitors quercetin (IC50 4.84 ± 6.43 μM) and baicalein (IC50 22.46 ± 1.32 μM). The most potent compounds in the series were compounds 7c (IC50 4.61 ± 3.21 μM), and 7f (IC50 6.64 ± 4.31 μM). These compounds were found least cytotoxic and showed 96.42 ± 1.3 % and 94.87 ± 1.6 % viability to cells at 0.25 mM concentration respectively. ADME and in silico studies supported the drug-likeness and binding studies of the molecules with the target enzyme.

Current energy crisis and environmental issues, including depletion of fossil fuels, rapid industrialization, and undesired CO2 emission resulting in global warming has created havoc for the global population and significantly affected the quality of life. In this scenario the environmental problems in the forefront of research priorities. Development of renewable energy resources particularly the efficient conversion of solar light to sustainable energy is crucial in addressing environmental problems. In this regard, the synthesis of semiconductors-based photocatalysts has emerged as an effective tool for different photocatalytic applications and environmental remediation. Among different photocatalyst options available, graphene and graphene derivatives such as, graphene oxide (GO), highly reduced graphene oxide (HRG), and doped graphene (N, S, P, B-HRG) have become rising stars on the horizon of semiconductors-based photocatalytic applications. Graphene is a single layer of graphite consisting of a unique planar structure, high conductivity, greater electron mobility, and significantly very high specific surface area. Besides, the recent advancements in synthetic approaches have led to the cost-effective production of graphene-based materials on a large-scale. Therefore, graphene-based materials have gained considerable recognition for the production of semiconducting photocatalysts involving other semiconducting materials. The graphene-based semiconductors photocatalysts surpasses electron-holes pairs recombination rate and lowers the energy band gap by tailoring the valence band (VB) and conduction band (CB) leading to the enhanced photocatalytic performance of hybrid photocatalysts. Herein, we have summarized the latest developments in designing and fabrication of graphene-based semiconducting photocatalysts using a variety of commonly applied methods such as, post-deposition methods, in-situ binding methods, hydrothermal and/or solvothermal approaches. In addition, we will discuss the photocatalytic properties of the resulting graphene-based hybrid materials for various environmental remediation processes such as; (i) clean H2 fuel production, photocatalytic (ii) pollutants degradation, (iii) photo-redox organic transformation and (iv) photo-induced CO2 reduction. On the whole, by the inclusion of more than 300 references, this review possibly covered in detail the aspects of graphene-based semiconductor photocatalysts for environmental remediation processes. Finally, the review will conclude a short summary and discussion about future perspectives, challenges and new directions in these emerging areas of research.

The facile, efficient, and straightforward preparation of electrode material for energy storage devices has drawn considerable interest for practical applications. In this study, we have synthesized the polyhedron Cu-doped ZnS (ZnS:Cu) structure on carbon cloth (CC) using a single-step glycol-assisted process. The highly interconnected polyhedron shaped ZnS:Cu functions as positive electrode material in an aqueous electrolyte for supercapacitor application. The ZnS:Cu polyhedron-like structures with higher electroactive sites and synergistic effect exhibited higher specific capacitance of 468 F g−1 at 1 Ag−1 and cycling stability of 890.5% after 5,000 cycles. The better electrochemical performance and higher cycling stability of ZnS:Cu can be dedicated to interconnected polyhedron-like structures, doping of Cu in ZnS, and binder-free electrode design. This underlines the potential of the Cu-doped ZnS-based supercapacitor for next-generation energy storage devices.

A series of 28 novel naproxen derivatives (4a-f, 5a-f, 6a-d, 7a-f, and 8a-f) have been designed, synthesized, and characterized. The synthesized derivatives were assessed as dual inhibitors for 15-lipoxygenase (LOX) and α-glucosidase enzymes and checked for cytotoxicity and ADME studies. The inhibitory potential of naproxen derivatives for 15- LOX was checked through two different methods, the UV absorbance method and the Chemiluminescence method. The biological activities result revealed that through the UV absorbance method, compound 4f (IC50 21.31 ± 0.32 µM) was found potent among the series followed by compounds 4e (IC50 36.53 ± 0.51 µM) and 4d (IC50 49.62 ± 0.12 µM) against standard drug baicalein (IC50 22.46 ± 1.32 µM) and quercetin (IC50 2.34 ± 0.35 µM), while through chemiluminescence method tested compounds showed significant 15-LOX inhibition at the range of IC50 1.13 ± 0.62 µM −123.47 ± 0.37 µM. Among these compounds, 4e (IC50 1.13 ± 0.62 µM), 5b (IC50 1.19 ± 0.43 µM), 8c (IC50 1.23 ± 0.35 µM) were found most potent inhibitors against quercetin (IC50 4.86 ± 0.14 µM), and baicalein (IC50 2.24 ± 0.13 µM). The chemiluminescence method was found more sensitive than the UV method to identify 15-LOX inhibitors. Interestingly all synthesized compounds showed significant α-glucosidase inhibitory activity (IC50 1.0 ± 1.13 µM − 367.2 ± 1.23 µM) even better than the standard drug acarbose (IC50 375.82 ± 1.76 µM), while compound 6c (IC50 1.0 ± 1.13 µM) and 7c (IC50 1.1 ± 1.17 µM) were found most potent compounds among the series even many folds better than the standard drug. The cell viability results showed that all compounds were less toxic, maintained cellular viability at the range of 99.8 ± 1.3% to 63.7 ± 1.5%. ADME and molecular docking studies supported drug-likeness and binding interactions of compounds with the targeted enzymes.

The formation of a C-C bond through Mizoroki-Heck cross-coupling reactions in water with efficient heterogeneous catalysts is a challenging task. In this current study, a highly reduced graphene oxide (HRG) immobilized palladium (Pd) nanoparticle based catalyst (HRG-Py-Pd) is used to catalyze Mizoroki-Heck cross-coupling reactions in water. During the preparation of the catalyst, amino pyrene is used as a smart functionalizing ligand, which offered chemically specific binding sites for the effective and homogeneous nucleation of Pd NPs on the surface of HRG, which significantly enhanced the physical stability and dispersibility of the resulting catalyst in an aqueous medium. Microscopic analysis of the catalyst revealed a uniform distribution of ultrafine Pd NPs on a solid support. The catalytic properties of HRG-Py-Pd are tested towards the Mizoroki-Heck cross-coupling reactions of various aryl halides with acrylic acid in an aqueous medium. Furthermore, the catalytic efficacy of HRG-Py-Pd is also compared with its non-functionalized counterparts such as HRG-Pd and pristine Pd NPs (Pd-NPs). Using the HRG-Py-Pd nanocatalyst, the highest conversion of 99% is achieved in the coupling reaction of 4-bromoanisol and acrylic acid in an aqueous solution in a relatively short period of time (3 h), with less quantity of catalyst (3 mg). Comparatively, pristine Pd NPs delivered lower conversion (∼92%) for the same reaction required a long reaction time and a large amount of catalyst (5.3 mg). Indeed, the conversion of the reaction further decreased to just 40% when 3 mg of Pd-NPs was used which was sufficient to produce 99% conversion in the case of HRG-Py-Pd. On the other hand, HRG-Pd did not deliver any conversion and was ineffective even after using a high amount of catalyst and a longer reaction time. The inability of the HRG-Pd to promote coupling reactions can be attributed to the agglomeration of Pd NPs which reduced the dispersion quality of the catalyst in water. Therefore, the high aqueous stability of HRG-Py-Pd due to smart functionalization can be utilized to perform other organic transformations in water which was otherwise not possible.

Complexes of transition metals [Co(II), Cd(II) and Mo(0)] with a new enaminone (PA) 3-chloro-4-((4-methoxyphenyl)amino)pent-3-en-2-one were synthesized and afterwards characterized by 1H NMR, 13C NMR, FAB-MS, UV–Vis, ICP-OES, TGA and FTIR. The spectroscopic and conductance data suggested that the ligand (PA) is attached to the metal ions in bidentate, neutral form through the nitrogen atom of amino group and the oxygen of carbonyl group. Metal complexes displayed octahedral geometries. In vitro urease inhibition and cytotoxic activities of all the compounds were evaluated. Results revealed that Co(II) complex (PA-Co) was even more significant than the reference drug thiourea. Analysis of the cytotoxicity indicated that, the Co(II) complex has more cytotoxic effect than enaminone ligand and other complexes when assessed on the human cancer cell lines MCF-7.Molecular docking simulation was also performed to find out the putative binding mode within the target protein.

Polysaccharides are beneficially used as drug carriers via prodrug formation and offer a mechanism for better effectiveness and delivery of the drug. The unique geometry of hydroxypropylcellulose (HPC), a polysaccharide, allows the attachment of drug molecules with a higher degree of substitution because the hydroxyls groups are projected outside the HPC chains. Therefore HPC-Naproxen conjugates, i.e., macromolecular prodrugs, were synthesized using a powerful acylation reagent carbonyldiimadazole (CDI) in N,N' dimethylacetamide (DMAc) solvent. The reactions were carried out at 80 °C under stirring for 24 h and inert environment. This reaction strategy appeared efficient to obtain a high degree of drug substitution (DS = 0.88–1.40) on the polymer parent chain as calculated by UV–visible spectrophotometry after hydrolysis of the samples. The method provides high efficacy as product yields were high (77–81%). Macromolecular prodrugs (MPDs) with different DS of naproxen designed were found soluble in organic solvents.

We numerically investigate the pulsatile flow and heat transfer of a micropolar fluid through a Darcy-Forchhmeir porous channel in the presence of wall transpiration. We use the central difference approximations for the spatial derivatives, whereas the time integration has been performed by employing the three steps explicit Runge-Kutta method to obtain the numerical solution. It is noted that the Darcy parameter tends to accelerate the fluid, whereas the Forchheimer quadratic drag parameter and the magnetic parameter would reduce the flow velocity. The effect of the steady component of the pressure gradient is to remarkably accelerate the flow whereas that of the oscillatory component is time-dependent. An increase in the Prandtl number tends to almost straighten the temperature profiles.

A continuous electrocatalytic reactor offers a promising method for producing fuels and value-added chemicals via electrocatalytic hydrogenation of biomass-derived compounds. However, such processes require a better understanding of the impact of different types of active electrodes and reaction conditions on electrocatalytic biomass conversion and product selectivity. In this work, Ni1−xPdx (x = 0.25, 0.20, and 0.15) alloyed nanostructures were synthesized as heterogeneous catalysts for the electrocatalytic conversion of furfural. Various analytical tools, including XRD, SEM, EDS, and TEM, were used to characterize the Ni1−xPdx catalysts. The alloyed catalysts, with varying Ni to Pd ratios, showed a superior electrocatalytic activity of over 65% for furfural conversion after 4.5 h of reaction. In addition, various experimental parameters on the furfural conversion reactions, including electrolyte pH, furfural (FF) concentration, reaction time, and applied potential, were investigated to tune the hydrogenated products. The results indicated that the production of 2-methylfuran as a primary product (S = 29.78% after 1 h), using Ni0.85Pd0.15 electrocatalyst, was attributed to the incorporation of palladium and thus the promotion of water-assisted proton transfer processes. Results obtained from this study provide evidence that alloying a common catalyst, such as Ni with small amounts of Pd metal, can significantly enhance its electrocatalytic activity and selectivity.

We optimized and validated an isocratic high-performance liquid chromatography (HPLC) assay for quantification of ceftiofur hydrochloride in bubaline plasma. Ceftiofur, its metabolic products and protein-bound residues were cleaved, derivatized into desfuroylceftiofur acetamide and injected into HPLC system. The mobile phase comprising of sodium dihydrogen phosphate (0.025 M, pH 7) and acetonitrile (34:66, v/v), was driven at a flow rate of 1 mL/min, and separation was achieved using C18 column. Isocratic elution was performed with an injection volume of 45 µL and analyte was scanned at 310 nm. The linearity range, limit of detection and limit of quantification were 0.1-10 µg/mL, 0.03 µg/mL and 0.11 µg/mL respectively. Moreover, the accuracy, precision and recovery remained within the acceptable limits. The assay was effectively applied for determining the concentration of ceftiofur in plasma samples collected from ceftiofur-treated buffalo calves.

The present problem addressed the transient behavior of convective heat and mass transfer characteristics across a curved surface under the influence of exothermic catalytic chemical reactions. The governing non-linear mathematical model wastransformed into a convenient form with the help of a primitive variable formulation. The final primitive formed model wassolved numerically by applying the finite difference method. The analysis of the above said computed numerical data in terms of oscillatory heat transfer, skin friction, and oscillatory mass transfer for various emerging parameters, such as the mixed convection parameter λT, modified mixed convection parameter λc, index parameter n, activation energy parameter E, exothermicparameter β, temperature relative parameter γ, chemical reaction parameter λ, and Schmidt number Sc is plotted in graphical form. An excellent agreement is depicted for oscillatory heat transfer behavior at the large value of activation energy E. The amplitude of heat transfer and prominent fluctuating response in mass transfer with a certain height is found at each value of the index parameter n with a good alteration. An increase in the activation energy led to an increase in the surface temperature, which yielded more transient heat transfer in the above-said mechanism. The main novelty of the current study is that first, we ensured the numerical results for the steady state heat and fluid flow and then these obtained results wereused in the unsteady part to obtain numerical results for the transient behavior of the heat and mass transfer mechanism.

The present investigation deals with the synthesis, characterization and pharmacological evaluation of four cadmium complexes (1–4) with Schiff bases (1L-4L) derived from the substituted amines and aryl aldehydes. Amantadine is reacted with different aryl aldehydes (salicylaldehyde, 3-ethoxysalicylaldehyde and 4-(diethylamino) salicylaldehyde) to prepare Schiff base ligands 1L-3L, while 4L was prepared using 4-methylaniline. The complexes were characterized by elemental analysis, spectroscopic techniques and thermal analysis, and the structure of one of the ligands, 3L was determined by X-ray crystallography. The spectroscopic data indicate that the ligands coordinate with Cd(II) in a bidentate fashion to give octahedral geometry. Single crystal XRD analysis shows that 3L is orthorhombic with the space group P212121. The ligands and their Cd(II) complexes were evaluated for antimicrobial activities, while the complexes were also investigated for inhibition effects towards an enzyme, alkaline phosphatase. The anti-microbial screening results showed that cadmium complex 1 exhibited significant antibacterial potential, particularly against Staphylococcus aureus with respect to the corresponding ligand suggesting that the complexes are more effective than their ligands for antimicrobial activity. In case of alkaline phosphatase inhibition screening, the synthesized cadmium complex 1 was found to maximally inhibit the activity of alkaline phosphatase in comparison to rest of three complexes.

The heat transmission properties along the non-magnetized geometries have been numerically obtainedby various researchers. These mechanisms are less interesting in engineering and industrial processes because of excessive heating. According to current studies, the surface is magnetized and the fluid is electrically conductive, which helps to lessen excessive surface heating. The main objective of the current analysis is to numerically compute the temperature-dependent density effect on magnetohydrodynamic convective heat-transfer phenomena of electrical-conductive fluid flow along the vertical magnetized and heated plate placed in a thermally stratified medium. For the purpose of numerical analysis, the theoretical process governing heat and magnetic intensity along a vertical magnetic plate is examined. By using suitable and well-known similarity transformations for integration, the non-linear coupled PDEs for the aforementioned electrical-conductive fluid flow mechanism are changed and subsequently converted into non-similar formulation. The Keller Box method is used to numerically integrate the final non-similar equations. The MATLAB software program plots the transformed algebraic equations graphically and quantitatively. The behavior of the physical quantities such asvelocity graph, magnetic field graph, and temperature plot along with their slopes that arerate of skin friction, the rate of heat transfer, and the rate of magnetic intensity for different parameters included in the flow model. The novelty of the current work is to compute the magneto-thermo analysis of electrically conducting flow along the vertical symmetric heated plate. First, we secure the numerical solution for steady part and then these results are used to find skin friction, heat transfer, and magnetic intensity. In the current work, the fluid becomes electrically conducing due to a magnetized surface which insulates heat during the mechanism and reduces the excessive heating. The results are excellent and accurate because they are satisfied by its given boundary conditions. Additionally, the current problems have a big impact on the production of polymer materials, glass fiber, petroleum, plastic films, polymer sheets, heat exchangers, catalytic reactors, and electronic devices.

In the current research work we have reported a series of N-aryl-2,3-dihydrobenzo[1,4]dioxine-6-sulfonamides 3 and their N-substituted derivatives 6 and 7, obtained from 3 with benzyl chloride and ethyl iodide, respectively. The synthesis was accomplished as a multistep sequence. The structural confirmations were established by 1H NMR, IR and EIMS spectral techniques. Butyrylcholinesterase (BChE), acetylcholinesterase (AChE) and lipoxygenase (LOX) enzymes were used in this study. It was observed that most of the compounds prepared exhibit a moderate activity against BChE and AChE but promisingly good activity against lipoxygenase. Among the parent sulfonamides 3a, 3b, 3c and 3e showed the proficient antimicrobial activities, while from the derivatives 6a, 6c, 7a, 7b and 7c were found active against the selected panel of bacterial and fungal species. Hemolytic activity was also conducted to check their therapeutic utility. All the compounds were computationally docked against LOX, BChE and AChE enzymes.

The present analysis addresses the impact of reduced gravity and magnetohydrodynamics on oscillating mixed-convective electricallyconducting fluid flow over a thermal, non-conducting horizontal circular cylinder. In reduced gravity, buoyancy forces may induce fluid motion due to a weak gravitational field but in non-gravity forces, fluid motion can be induced by a variety of factors, including surface tension and density variations. The fluid motion is governed by connected nonlinear partial differential equations which are converted into convenient equations by applying a finite-difference scheme with the primitive transformation and a Gaussian elimination technique. The numerical solutions of the connected dimensionalized equations were obtained for various emerging dimensionless parameters, reduced gravity parameter Rg, Prandtl number Pr, and some other fixed parameters. First, the fluid velocity, temperature distribution and magnetic-field profiles were obtained and then these profiles were used to examine the oscillating quantities of skinfriction, oscillating heat transfer and oscillating rate of currentdensity. The FORTRAN software was used for the numerical results and these results were displayed on Tech Plot. The fluid velocity and magnetic profile were increased at the π/2 station as reduced gravity increased but the dimensionless temperature of the fluid attained a maximum magnitude as reduced gravity was decreased. The larger amplitude of the oscillating coefficients of τt and τm was concluded with a prominent variation for each λ in the presence of reduced gravity. Physically, this could be because an increase in the decreased gravity parameter impacts the fluid flow’s driving potential along a thermal, non-conducting horizontalcylinder.

Two series of new N-aryl derivatives (9a-j; 10a-j) of 2-(4-ethyl-5-(3-chlorophenyl)-4H-1,2,4-triazol-3-ylthio)acetamide and 2-(4-phenyl-5-(3-chlorophenyl)-4H-1,2,4-triazol-3-ylthio)acetamide were synthesized by the successive conversions of 3-chlorobenzoic acid (a) into its respective ester (1) hydrazide (2), and into N-substituted 1,2,4-triazole (5, 6) via 3 and 4, respectively. The target compounds (9a-j; 10a-j) were obtained by the reaction of N-substituted 1,2,4-triazole (5, 6) with various electrophiles (8a-j), in N,N-dimethyl formamide (DMF) and sodium hydride (NaH). The synthesized analogues were characterized by using FTIR, 1H, 13C NMR spectroscopy, EIMS and HREIMS spectrometry. All the synthesized compounds, 9a-j and 10a-j, were evaluated for their inhibitory potential against acetylcholinesterase (AChE) and butyrylcholinestrase (BChE), where these compounds showed moderate to good activities against the tested enzymes. Compounds 9j and 10f displayed potent inhibitory potential (IC50 5.41 ± 0.24 & 13.57 ± 0.31 μM, respectively) against AChE while compound 9j exhibited potent inhibitory activity (IC50 7.52 ± 0.18 μM) against BChE. Other compounds showed good to moderate inhibitory activities against the said enzymes in the range of IC50 14.29–43.94 μM for AChE and IC50 21.59–41.54 μM for BChE. To rationalize the binding site interactions, docking studies were carried out. All docked compounds were found to bind in the active site with similar binding orientation and favorable binding interactions with the surrounding amino acids.

Drought is one of the most important abiotic stress factors limiting maize production worldwide. The objective of this study was to investigate whether photoprotection of PSII was associated with the degree of drought tolerance and yield in three maize hybrids (30Y87, 31R88, P3939). To do this, three maize hybrids were subjected to three cycles of drought, and we measured the activities of photosystem II (PSII) and photosystem I (PSI). In a second field experiment, three maize hybrids were subjected to drought by withholding irrigation, and plant water status, yield and yield attributes were measured. Drought stress decreased leaf water potential (ΨL) in three maize hybrids, and this reduction was more pronounced in hybrid P3939 (−40%) compared to that of 30Y87 (−30%). Yield and yield attributes of three maize hybrids were adversely affected by drought. The number of kernels and 100-kernel weight was the highest in maize hybrid 30Y87 (−56%, −6%), whereas these were lowest in hybrid P3939 (−88%, −23%). Drought stress reduced the quantum yield of PSII [Y(II)], photochemical quenching (qP), electron transport rate through PSII [ETR(II)] and NPQ, except in P3939. Among the components of NPQ, drought increased the Y(NPQ) with concomitant decrease in Y(NO) only in P3939, whereas Y(NO) increased in drought-stressed plants of hybrid 30Y87 and 31R88. However, an increase in cyclic electron flow (CEF) around PSI and Y(NPQ) in P3939 might have protected the photosynthetic machinery but it did not translate in yield. However, drought-stressed plants of 30Y87 might have sufficiently downregulated PSII to match the energy consumption in downstream biochemical processes. Thus, changes in PSII and PSI activity and development of NPQ through CEF are physiological mechanisms to protect the photosynthetic apparatus, but an appropriate balance between these physiological processes is required, without which plant productivity may decline.

In this paper, a comprehensive numerical study is presented for studying the MHD flow and heat transfer characteristics of non-Newtonian micropolar fluid through a porous medium between two stretchable porous disks. The system of governing equations is converted into coupled nonlinear ordinary ones through a similarity transformation, which is then solved using Quasi-linearization method. The effects of the magnetic field, the vortex viscosity, the microinertia density, the spin gradient viscosity, the stretching of the disks, the viscous dissipation, the ratio of momentum diffusivity to thermal viscosity, the radiation and the porosity of the medium on the flow, microrotation and temperature fields are discussed through tables and graphs.

The aim of the research work was to synthesize different biologically active carbamate derivatives bearing 2-furoyl-1-piperazine and having modest toxicity. The synthesis was completed in multiple steps. The structural confirmation of all the synthesized compounds was carried out by EI-MS, IR and 1H-NMR spectral data. The enzyme inhibition and antibacterial potential of the synthesized compounds was evaluated. Moreover, the cytotoxicity of the compounds was also checked to find their utility as possible therapeutic agents. All the compounds were active against acetylcholinesterase enzyme especially 12 and 14 showed very good inhibitory potential relative to Eserine, a reference standard. Almost all the compounds showed good activities against the both Gram-positive and Gram-negative bacterial strains.

Public transport use has drastically declined during the COVID-19 pandemic because the virus spreads through close contact with infected people and contaminated surfaces, especially in closed-environments. Evidence suggests that following the necessary safety guidelines can limit the spread of the virus, however, non-compliance to precautionary measures has been reported widely. Ignoring the precautionary measures may lead to quick transmission of the virus since public transport vehicles generally resemble closed-environments. This study explores people’s intentions to use public transport during the COVID-19 pandemic while adhering to precautionary measures. For this purpose, a total of 1516 useable responses were collected through a questionnaire survey conducted in Lahore, Pakistan. Regression models were developed to model the intentions to use public transport during the pandemic, to adhere to the precautionary measures while using public transport during the pandemic, and to use public transport while suffering from COVID-19 disease. The results of this study will help in understanding the intentions of the public transport users during the COVID-19 pandemic. It will also provide insights for policymakers and public transport operators about further necessary actions to promote safe public transport use during the current and any possible future pandemics. As public transport use declined during the pandemic, policy implications for alternative mobility options such as demand-responsive-transport (DRT) are also presented. Considering the study results, a policy interventions framework is proposed to promote the safe use of various public transport modes, particularly in developing regions.

App-based demand-responsive transit (DRT) services are emerging where conventional public transport is unable to meet the demand. SWVL (choice A) and Airlift (choice B) are two such DRT bus services operating in Lahore, Pakistan. It is important for the policy makers and operators to evaluate the satisfaction levels of the passengers using these services. This study evaluated passengers’ satisfaction regarding choice A and choice B through a questionnaire survey. A total of 440 responses were collected from the users of the DRT services through personal interviews and a web-based approach. Factor analysis on the collected data produced two underlying factors, namely service-attributes and bus ambiance. Ordinal regression showed that the service-attributes and ambiance were significant predictors of overall satisfaction levels about choice A. Service-attributes indicated a larger positive impact on overall satisfaction with choice A as compared to ambiance. Although the ordinal model for choice B fitted the data well, the predictors were found to be insignificant. The results offer an insight into which predictors affect the overall satisfaction and how it can be improved.

To develop a strategy for the eradication of Cu2+ and Zn2+ from contaminated waters, the waste biomass of Mangifera indica was pretreated physically (autoclaved, boiled and heated) for assessing the uptake capacity of native and pretreated biomass for Cu2+ and Zn2+ biosorption on batch scale, concentrating on pH, pretreatment, biosorbent dose, metal concentration, contact time and temperature as operational parameters. To measure the goodness-of-fit error functions as sum of square error (SSE), chi-square (χ2) and residual root mean square error (RMSE) were used. Best results were obtained at pH 5 (80.65 mg/g) and 6 (94.25 mg/g) for Cu2+ and Zn2+, respectively, with autoclaved leaves. Sorption capacity of biomasses was found to be decreased with increase in biosorbent dose and temperature while it increased with increase in metal ion concentration and with time. Freundlich isotherm was found favorable to describe sorption mechanism, whereas pseudo-second-order kinetic model was best employed to describe sorption rate.

The float formulation is a strategy to improve the bioavailability of drugs by gastroretentive drug delivery system (GRDDS). A drug delivery model based on swellable and reswellable low density biopolymers has been designed to evaluate its drug release profile using ranitidine (RNT) as a model drug and formulations have been prepared utilizing 32 factorial designs. The drug release (DR) data has been subjected to various kinetic models to investigate the DR mechanism. A reduction in rate has been observed by expanding the amounts of PSG and LSG parts, while an expansion has been noted by increasing the concentration of tragacanth (TG) and citric acid (CA) with an increment in floating time. The stearic acid (SA) has been used to decrease the lag time because a decrease in density of system was observed. The kinetic analysis showed that the optimized formulation (S4F3) followed zero-order kinetics and power law was found to be best fitted due to its minimum lag time and maximum floating ability. The resemblance of observed and predicted values indicated the validity of derived equations for evaluating the effect of independent variables while kinetic study demonstrated that the applied models are feasible for evaluating and developing float for RNT.

This study was carried out to appraise whether or not the exogenous application of a potential osmoprotectant, proline, could ameliorate the adverse effects of drought stress on maize seed and seed oil composition, as well as oil antioxidant activity. Water stress reduced the kernel sugar, oil, protein and moisture contents and most of the seed macro- and micro-elements analyzed in both maize cultivars but it increased the contents of seed fiber and ash. Water stress increased the oil oleic acid content with a subsequent decrease in the amount of linoleic acid, resulting in an increased oil oleic/linoleic ratio for both maize cultivars. However, no variation was observed in oil stearic and palmitic acids content due to water stress. A considerable drought induced an increase in seed oil α-, γ-, δ- and total tocopherols and flavonoids were observed in both maize cultivars. However, oil phenolic and carotenoid content as well as 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity decreased. Foliar-applied proline significantly increased the content of seed sugar, oil, protein, moisture, fiber and ash in both maize cultivars under well irrigated and water deficit conditions. Furthermore, exogenous application of proline increased the oil oleic and linoleic acid contents. The concentrations of antioxidant compounds namely phenolics, carotenoids, flavonoids and tocopherols estimated in the seed oil increased due to foliar-applied proline under water deficit conditions that was positively correlated with the enhanced oil DPPH free radical scavenging activity. Moreover, the increase in the contents of these antioxidant compounds and oil antioxidant activity due to the foliar application of proline was noted to be more pronounced under water deficit conditions.

Heterocyclic compounds are the most attractive class for researchers due to their biological activities. In the undertaken research, a number of N-(5-chloro-2-methoxyphenyl)-4-(5-substituted-1,3,4-oxadiazol-2-ylthio)butanamide (6a–k) compounds were prepared by converting multifarious phenyl/aryl/aralkyl/heterocyclic organic acids (1a–k) consecutively into the corresponding esters (2a–k), hydrazides (3a–k) and 5-substituted-1,3,4-oxadiazol-2-thiols (4a–k). Finally, the target compounds 6a–k were synthesized by stirring 5-substituted-1,3,4-oxadiazol-2-thiols (4a–k) with N-(5-chloro-2-methoxyphenyl)-4-bromobutanamide (5) in the presence of N,N-dimethylformamide (DMF) and sodium hydride (NaH). The structure elucidation of the synthesized compounds was processed through 1H-NMR, IR and mass spectral data. The synthesized compounds were screened against lipoxygenase enzyme (LOX) and showed moderately good activities relative to the reference standard Baicalein.

The present study reports the composition and variation of fatty acids, sterols, tocopherols and γ-oryzanol among selected varieties namely Basmati Super, Basmati 515, Basmati 198, Basmati 385, Basmati 2000, Basmati 370, Basmati Pak, KSK-139, KS-282 and Irri-6 of Pakistani rice (Oryza sativa L). Oil content extracted with n-hexane from different varieties of brown rice seed (unpolished rice) ranged from 1.92% to 2.72%. Total fatty acid contents among rice varieties tested varied between 18240 and 25840 mg/kg brown rice seed. The rice tested mainly contained oleic (6841–10952 mg/kg) linoleic (5453–7874 mg/kg) and palmitic acid (3613–5489 mg/kg). The amounts of total phytosterols (GC and GC-MS analysis), with main contribution from β-sitosterol (445–656 mg/kg), campesterol (116–242 mg/kg), ∆5-avenasterol (89–178 mg/kg) and stigmasterol (75–180 mg/kg) were established to be 739.4 to 1330.4 mg/kg rice seed. The content of α-, γ- and δ-tocopherols as analyzed by HPLC varied from 39.0–76.1, 21.6–28.1 and 6.5–16.5 mg/kg rice seed, respectively. The amounts of different γ-oryzanol components (HPLC data), identified as cycloartenyl ferulate, 24-methylene cycloartanyl ferulate, campesteryl ferulate and β-sitosteryl ferulate, were in the range of 65.5–103.6, 140.2–183.1, 29.8–45.5 and 8.6–10.4 mg/kg rice seed, respectively. Overall, the concentration of these bioactives was higher in the Basmati rice cultivars showing their functional food superiority. In conclusion, the tested varieties of Pakistani rice, especially the Basmati cultivars, can provide best ingredients for functional foods.

The role of plant hormone abscisic acid (ABA) in plants under drought stress (DS) is crucial in modulating physiological responses that eventually lead to adaptation to an unfavorable environment; however, the role of this hormone in modulation of glycinebetaine (GB) metabolism in maize particularly at the seedling stage is still poorly understood. Some hydroponic experiments were conducted to investigate the modulation role of ABA on plant growth, water relations and GB metabolism in the leaves of two maize cultivars, Zhengdan 958 (ZD958; drought tolerant), and Jundan 20 (JD20; drought sensitive), subjected to integrated root-zone drought stress (IR-DS) simulated by the addition of polyethylene glycol (PEG, 12% w/v, MW 6000). The IR-DS substantially resulted in increased betaine aldehyde dehydrogenase (BADH) activity and choline content which act as the key enzyme and initial substrate, respectively, in GB biosynthesis. Drought stress also induced accumulation of GB, whereas it caused reduction in leaf relative water content (RWC) and dry matter (DM) in both cultivars. The contents of ABA and GB increased in drought-stressed maize seedlings, but ABA accumulated prior to GB accumulation under the drought treatment. These responses were more predominant in ZD958 than those in JD20. Addition of exogenous ABA and fluridone (Flu) (ABA synthesis inhibitor) applied separately increased and decreased BADH activity, respectively. Abscisic acid application enhanced GB accumulation, leaf RWC and shoot DM production in both cultivars. However, of both maize cultivars, the drought sensitive maize cultivar (JD20) performed relatively better than the other maize cultivar ZD958 under both ABA and Flu application in view of all parameters appraised. It is, therefore, concluded that increase in both BADH activity and choline content possibly resulted in enhancement of GB accumulation under DS. The endogenous ABA was probably involved in the regulation of GB metabolism by regulating BADH activity, and resulting in modulation of water relations and plant growth under drought, especially in the drought sensitive maize cultivar JD20.

Betaine, a non-toxic osmoprotectant, is believed to accumulate considerably in plants under stress conditions to maintain the osmotic pressure and promote a variety of processes involved in growth and development. Phosphoethanolamine N-methyltransferase (PEAMT), a key enzyme for betaine synthesis, is reported to be regulated by its upstream promoter. In the present investigation, by using the transgenic approach, a 1048 bp long promoter region of ZmPEAMT gene from Zea mays was cloned and functionally characterized in tobacco. Computational analysis affirmed the existence of abiotic stress responsive cis-elements like ABRE, MYC, HST, LST etc., as well as pathogen, wound and phytohormone responsive motifs. For transformation in tobacco, four 5′-deletion constructs of 826 bp (P2), 642 bp (P3), 428 bp (P4) and 245 bp (P5) were constructed from the 1048 bp (P1) promoter fragment. The transgenic plants generated through a single event exhibited a promising expression of GUS reporter protein in the leaf tissues of treated with salt, drought, oxidative and cold stress as well as control plants. The GUS expression level progressively reduced from P1 to P5 in the leaf tissues, whereas a maximal expression was observed with the P3 construct in the leaves of control plants. The expression of GUS was noted to be higher in the leaves of osmotically- or salt-treated transgenic plants than that in the untreated (control) plants. An effective expression of GUS in the transgenic plants manifests that this promoter can be employed for both stress-inducible and constitutive expression of gene(s). Due to this characteristic, this potential promoter can be effectively used for genetic engineering of several crops.