Medicinal Potential of Isoflavonoids: Polyphenols That May Cure Diabetes

In recent years, there is emerging evidence that isoflavonoids, either dietary or obtained from traditional medicinal plants, could play an important role as a supplementary drug in the management of type 2 diabetes mellitus (T2DM) due to their reported pronounced biological effects in relation to multiple metabolic factors associated with diabetes. Hence, in this regard, we have comprehensively reviewed the potential biological effects of isoflavonoids, particularly biochanin A, genistein, daidzein, glycitein, and formononetin on metabolic disorders and long-term complications induced by T2DM in order to understand whether they can be future candidates as a safe antidiabetic agent. Based on in-depth in vitro and in vivo studies evaluations, isoflavonoids have been found to activate gene expression through the stimulation of peroxisome proliferator-activated receptors (PPARs) (α, γ), modulate carbohydrate metabolism, regulate hyperglycemia, induce dyslipidemia, lessen insulin resistance, and modify adipocyte differentiation and tissue metabolism. Moreover, these natural compounds have also been found to attenuate oxidative stress through the oxidative signaling process and inflammatory mechanism. Hence, isoflavonoids have been envisioned to be able to prevent and slow down the progression of long-term diabetes complications including cardiovascular disease, nephropathy, neuropathy, and retinopathy. Further thoroughgoing investigations in human clinical studies are strongly recommended to obtain the optimum and specific dose and regimen required for supplementation with isoflavonoids and derivatives in diabetic patients.     

Universiti Malaysia Pahang examination timetabling problem: scheduling invigilators

This paper presents a real-world examination timetabling problem from Universiti Malaysia Pahang (UMP), Malaysia. The problem involves assigning invigilators to examination rooms. This problem has received less attention than the examination timetabling problem from the research community partly because no data sets are available in the literature. In modelling, and solving, this problem we assume that there is already an examination timetable in place (this was the subject of our previous work) and the task is to assign invigilators to that timetable. The contributions of this paper are to formally define the invigilator scheduling problem and to present a constructive algorithm that is able to produce good quality solutions that are superior to the solutions produced when using the university's current software. We also include additional constraints taking into account the comments made by the invigilators, which the current system fails to capture. The model we present, we believe, accurately reflects the real-world problem, capturing various aspects of the problem that have not been presented before in the scientific literature. Moreover, the proposed approach adheres to all hard constraints, which the university's current system fails to do.     

Influence of ionic and nonionic hydrotropes on micellar behavior of a cationic gemini surfactant butanediyl-1,4-bis(dimethylcetylammonium bromide)

Micellization of binary systems of a cationic gemini surfactant butanediyl-1,4-bis(dimethylcetylammonium bromide) (16-4-16) and cationic/nonionic hydrotropes (aniline-hydrochloride, 2-methylanilinehydrochloride, 4-methylanilinehydrochloride, hydroxybenzene, 1,3-benzenediol, benzene-1,2,3-triol) have been studied using a conductometric technique. The critical micelle concentrations (cmc) for different mixing mole fractions at different temperatures have been calculated. To explain and compare the results, theoretical models of Clint, Rubingh and Motomura have been used to obtain the ideal cmc, mixed micelle composition, interaction parameters (β(m)), free energies of micellization, and activity coefficients. The mixtures show nonideal behavior and the interactions between the surfactants and the hydrotropes are synergistic in nature which is confirmed by high negative β(m) values and low values of the activity coefficients. Thermodynamic parameters were also obtained from the temperature dependence of the cmc values.     

A great deluge algorithm for a real-world examination timetabling problem

The examination timetabling problem involves assigning exams to a specific or limited number of timeslots and rooms with the aim of satisfying all hard constraints (without compromise) and satisfying the soft constraints as far as possible. Most of the techniques reported in the literature have been applied to simplified examination benchmark data sets. In this paper, we bridge the gap between research and practice by investigating a problem taken from the real world. This paper introduces a modified and extended great deluge algorithm (GDA) for the examination timetabling problem that uses a single, easy to understand parameter. We investigate different initial solutions, which are used as a starting point for the GDA, as well as altering the number of iterations. In addition, we carry out statistical analyses to compare the results when using these different parameters. The proposed methodology is able to produce good quality solutions when compared with the solution currently produced by the host organisation, generated in our previous work and from the original GDA.     

Polymer-Assisted Electrophoretic Synthesis of N-Doped Graphene-Polypyrrole Demonstrating Oxygen Reduction with Excellent Methanol Crossover Impact and Durability

The design and synthesis of metal-free catalysts with superior electrocatalytic activity, high durability, low cost, and under mild conditions is extremely desirable but remains challenging. To address this problem, a polymer-assisted electrochemical exfoliation technique of graphite in the presence of an aqueous acidic medium is reported. This simple, cost-effective, and mass-scale production approach could open the possibility for the synthesis of high-quality nitrogen-doped graphene–polypyrrole (NG-PPy). The NG-PPy catalyst displays an improved half wave potential (E_1/2=0.77 V) in alkaline medium compared with G-PPy (E_1/2=0.66 V). Most importantly, this catalyst demonstrates excellent stability with high methanol tolerance, and it outperforms the commercial Pt/C catalyst and other previously reported metal-free catalysts. The content of graphitic nitrogen atoms is the key factor for the enhancement of electrocatalytic activity towards oxygen reduction reactions (ORR). Interestingly, the NG-PPy catalyst can be used as a cathode material in a zinc–air battery, which demonstrates a higher peak power density (59 mW cm⁻²) than G-PPy (36.6 mW cm⁻²), highlighting the importance of the low-cost material synthesis approach towards the development of metal-free efficient ORR catalysts for fuel cell and metal–air battery applications. Remarkably, the polymer-assisted electrophoretic exfoliation of graphite with a high yield (≈88 wt %) of few-layer graphene flakes could pave the way towards the mass production of high-quality graphene for a variety of applications.     

Correction to: Pore Space and Fluid Phase Characterization in Round and Angular Partially Saturated Sands Using Radiation‑Based Tomography and Persistent Homology

Transport in Porous Media - A correction to this paper has been published: https://doi.org/10.1007/s11242-021-01630-1     

Modulation of aggregation behavior of amphiphilic drug AMT under the influence of polymer molecular weight and composition

The purpose of this study was to determine the aggregation behavior of amphiphilic drug amitriptyline hydrochloride (AMT) and to search for means which boost/suppress the aggregation behavior. Polyethylene glycols (PEGs) nonionic polymers (which are used as pharmaceutical excipients) of varying molecular weights from 400 to 35,000 were tested. To know their effect on the micellization and interfacial behavior of the drug, the critical micelle concentration (CMC) and critical aggregation concentration (CAC) were determined in presence of various polymers by tensiometric and conductivity methods. The CAC values were found to decrease while the CMC values increased with increase in the polymer concentration. The thermodynamic parameters were evaluated where ΔG°(mic) and ΔG°(agg) are found to be negative, confirming the feasibility of interaction between AMT and polymers.