Imprinted silica nanoparticles coated with N‐propylsilylmorpholine‐4‐carboxamide for the determination of m‐cresol in synthetic and real samples

m‐Cresol‐imprinted silica nanoparticles coated with N‐propylsilylmorpholine‐4‐carboxamide have been developed that contain specific pockets for the selective uptake of m‐cresol. Silica nanoparticles were synthesized by a sol–gel process followed by functionalization of their surface with N‐propylsilylmorpholine‐4‐carboxamide. The formation of m‐cresol‐imprinted silica nanoparticles was confirmed by UV‐Vis spectrophotometry, infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. Electron microscopic studies revealed the formation of monodispersed imprinted silica nanoparticles with spherical shape and an average size of 83 nm. The developed nanoparticles were filled in a syringe and used for the extraction of m‐cresol from aqueous samples followed by quantification using high‐performance liquid chromatography with diode array detection. Various adsorption experiments showed that developed m‐cresol‐imprinted silica nanoparticles exhibited a high adsorption capacity and selectivity and offered a fast kinetics for rebinding m‐cresol. The chromatographic quantification was achieved using mobile phase consisting of acetonitrile/water (70:30 v/v) at an isocratic flow rate of 1.0 mL/min using a reversed‐phase C₁₈ column and detection at λ_max = 275 nm. The limits of detection and quantification were 1.86 and 22.32 ng/mL, respectively, for the developed method. The percent recoveries ranged from 96.66–103.33% in the spiked samples. This combination of this nanotechnique with molecular imprinting was proved as a reliable, sensitive and selective method for determining the target from synthetic and real samples.     

Solvent- and Substrate-Induced Chiroptical Inversion in Amphiphilic,Biocompatible Glycoconjugate Supramolecules: Shape-Persistent Gelation,Self-Healing,and Antibacterial Activity

We have shown solvent- and substrate-dependent chiral inversion of a few glycoconjugate supramolecules. (Z)-F-Gluco, in which d -glucosamine has been attached chemically to Cbz-protected l -phenylalanine at the C terminus, forms a self-healing hydrogel through intertwining of the nanofibers wherein the gelators undergo lamellar packing in the β-sheet secondary structures with a single chiral handedness. Dihybrid (Z)-F-gluco nanocomposite gel was prepared by in-situ formation of silver nanoparticles AgNPs in the gel; this enhances the mechanical properties of the composite gel through physical crosslinking without altering the packing pattern. In contrast, (Z)-L-gluco bearing an l -leucine moiety does not form a hydrogel but an organogel. Interestingly, the chiral handedness of the aggregates of (Z)-L-gluco can be reversed by choosing suitable solvents. In addition to self-healing behavior, (Z)-L-gluco gel revealed shape persistency. Further, (Z)-F-gluco hydrogel is benign, nontoxic, non-immunogenic, and non-allergenic in animal cells. AgNP-loaded (Z)-F-gluco hydrogel showed antibacterial activity against both Gram-positive and Gram-negative bacteria.     

A game theory-based approach for the study of inter-interference in coexisting wireless body area networks

A wireless body area network (WBAN) enables the continuous monitoring of health conditions including heart rate, temperature, and glucose levels. It is composed of several sensors that are placed on the body. The network's performance is significantly affected by the unpredictable movements of the human body. Due to the varying proximities between them, the existence of several WBANs creates a challenge when mobility is involved. In this fictitious scenario, we consider a park area with both mobile and static WBANs or WBAN-equipped individuals passing through the park who have varying degrees of mobility. When a mobile WBAN passes a static WBAN and is within a minimum distance of the static WBAN, they pair up and immediately interfere. Inter-interference caused by WBANs operating in a limited area causes packet loss and performance deterioration. In this work, static WBAN locations are optimised to minimise interference and system inter-interference problems are addressed by a game theoretic method. This paper formulates a flexible game theoretic framework to study WBAN coexistence using the expected pay-off function considering a two-player game. It is observed from the results obtained that the probability of interference caused by fast mobile WBANs is reduced to a maximum of 50% compared with that caused by slow mobile WBANs thereby reducing the need for relocation of static WBANs.     

Sleepy keeper style based Low Power VLSI Architecture of a Viterbi Decoder applying for the Wireless LAN Operation sustainability

Analog Integrated Circuits and Signal Processing - Remarkable progress in the field of wireless communication has created a research interest for Viterbi decoder with long duration of battery life,...     

Quantification of fenoprofen in human plasma using UHPLC–tandem mass spectrometry for pharmacokinetic study in healthy subjects

A rapid, simple and sensitive ultra-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method has been developed to quantify fenoprofen, a nonsteroidal anti-inflammatory drug in human plasma for a pharmacokinetic study in healthy subjects. Owing to high levels of protein binding, protein precipitation followed by solid-phase extraction was employed for the extraction of fenoprofen and fenoprofen-d3 (used as internal standard) from 200 μL human plasma. Separation was performed on a BEH C₁₈ (50 × 2.1 mm, 1.7 μm) column using methanol−0.2% acetic acid in water (75:25, v/v) under isocratic elution. Electrospray ionization was operated in the negative mode for sample ionization. Ion transitions used for quantification in the selected reaction monitoring mode were m/z 241/197 and m/z 244/200 for fenoprofen and fenoprofen-d3, respectively. Under the optimized conditions, fenoprofen showed excellent linearity in the concentration range 0.02–20 μg/mL (r² ≥ 0.9996), adequate sensitivity, favorable accuracy (96.4–103.7%) and precision (percentage coefficient of variation ≤4.3) with negligible matrix effect. The validated method was successfully applied to a pharmacokinetic study of fenoprofen in healthy subjects. The significant features of the method include higher sensitivity, small plasma volume for processing and a short analysis time.     

Molecular dynamics simulations of the chiral recognition mechanism for a polysaccharide chiral stationary phase in enantiomeric chromatographic separations

We use explicit-solvent fully atomistic molecular dynamics (MD) simulations, permitting all the interactions between the atoms constituting the polymeric chiral stationary phase (CSP), the solvent molecules and the drug molecule enantiomers, to better understand the chiral recognition mechanism that makes chromatographic separation possible. Using amylose tris(3,5-dimethylphenyl carbamate) (ADMPC) as prototype, three solvent systems, and ten racemates as solutes, we seek a molecular dynamics average quantity that could serve as a metric that predicts which of the two enantiomers will elute first and also correlates with the ratio of retention times for enantiomers. To better understand the molecular dynamic chiral recognition that provides the discrimination which results in the separation of enantiomers by high performance liquid chromatography, we examine the differences in hydrogen bonding lifetimes in various donor–acceptor pairs between the drugs and the ADMPC, and map out the differences in ring-ring interactions between the drugs and the ADMPC. Several MD average quantities related to hydrogen-bonding lifetimes correlate with the ratio of retention times for the enantiomers. One of these quantities provides a prediction of the correct elution order 90% of the time, and the ratios of these quantities for the enantiomers provide linear correlation (0.85 coefficient) with experimental separation factors.     

A Survey of Localization Systems in Internet of Things

Mobile Networks and Applications - With the rapid development in wireless technologies and the Internet, the Internet of Things (IoT) is envisioned to be an integral part of our daily lives....     

Bioprocessing of Biodiesel Industry Effluent by Immobilized Bacteria to Produce Value-Added Products

Biodiesel industrial effluent rich in crude glycerol (CG) was processed to produce value-added product. Under continuous culture system, Bacillus amyloliquefaciens strain CD16 immobilized within its biofilm, produced 3.2 L H₂/day/L feed, over a period of 60 days at a hydraulic retention time of 2 days. The effective H₂ yield by B. amyloliquefaciens strain CD16 was 165 L/L CG. This H₂ yield was 1.18-fold higher than that observed with non-biofilm forming Bacillus thuringiensis strain EGU45. Bioprocessing of the effluent released after this stage, by recycling it up to 25% did not have any adverse effect on H₂ production by strain EGU45; however, a 25% reduction in yield was recorded with strain CD16. Biofilm forming H₂ producers thus proved effective as self-immobilizing system leading to enhanced process efficiency.     

Synthesis of tubuphenylalanine and epi-tubuphenylalanine via regioselective aziridine ring opening with carbon nucleophiles followed by hydroboration-oxidation of 1,1-substituted amino alkenes

An efficient synthesis of N-Boc-tubuphenylalanine benzyl ester (N-Boc-Tup-OBn, 1a) and N-Boc-epi-tubuphenylalanine benzyl ester (N-Boc-epi-Tup-OBn, 1b) is reported herein. Regioselective aziridine 4 ring opening with carbon nucleophiles followed by hydroboration of 1,1-substituted aminoalkene 3 using 9-BBN and subsequent oxidation in an alkaline medium are used as the key steps to provide N-tosyl 1,4-aminoalcohols. The 1,4-aminoalcohols are successfully transformed into the desired products with an overall yield of 23% for 1a and 11% for 1b over 8 consecutive steps separately.     

Facile synthesis of novel bis-derivatives of 2,5-diamino-thiadiazole/<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-thiocarbohydrazide and their biological perspective

A series of new bis derivatives of 2,5-thiadiazole and N,N′-thiocarbohydrazide along with their transition metal complexes were synthesized by green methods (sonochemical and microwave), i.e., energy and time efficient and operationally more simple than existing conventional methods. All the synthesized compounds were fully characterized by routine analytical techniques and subjected to a preliminary biological screening. These novel characterized compounds were screened for antimicrobial activities and showed promising results. A few potent compounds were also tested for antitumor activities against MDA-MB231 (human breast carcinoma cell line) and compound 5 has emerged as a potential antitumor compound followed by compound 2, 10 and 9, with IC₅₀ values of 29.48, 32.25, 32.34 and 34.34 μg/ml, respectively. To understand the binding interactions of these compounds, in silico studies were performed using the AUTODOCK 4.2 suite and found to be supportive of the experimental results.