Carbon fibers modified with polypyrrole for headspace solid phase microextraction of trace amounts of 2-pentyl furan from breath samples

This study introduces micrometric carbon strands as a suitable fiber for headspace solid phase microextraction. Compared to previous supports, carbon fibers have mechanical flexibility, wide thermal expansion, and a large surface area, which is an important factor in headspace solid phase microextraction. The electrophoretic technique was applied to modify the surface of stainless steel and carbon fibers with polypyrrole. Modified carbon fibers were used for extraction of 2-pentylfuran (2-PF) as a model analyte from patients� breath and coffee samples. 2-PF belongs to the furan family, which was suggested as a biomarker for Aspergillus fumigatus and was classified as a possible carcinogen. 2-PF can be found in many heat-processed foods and drinks. The separation and detection of the analyte was performed by gas chromatography coupled to mass spectrometry. The effective factors in the extraction performance of the analyte by carbon fiber supports were investigated and optimized. Under optimized extraction conditions (temperature, 20 °C; time, 15 min; desorption temperature, 200 °C; desorption time, 2 min; salt concentration, 10 w/v; and stirring rate, 700 rpm), the limit of detection was calculated as 0.05 ng mL�1, whereas repeatability and fiber-to-fiber reproducibility (RSD ) was found to be in the range of 3.2�4.1. The experimental results showed that the proposed fiber had greater extraction performance for 2-pentylfuran. © 201

Fabrication of Pd NPs on pectin-modified Fe3O4 NPs: A magnetically retrievable nanocatalyst for efficient C-C and C-N cross coupling reactions and an investigation of its cardiovascular protective effects

The present report represents the synthesis of a novel Pd NPs immobilized over a natural polysaccharide (pectin) coated Fe3O4 magnetic nanocomposite material (Fe3O4@pectin/Pd) for investigating the cardiovascular protective effects. The biomolecular functionalization not only stabilizes the ferrite nanoparticles from agglomeration but also provides an environment for the biogenic reduction of Pd2+ ions. This protocol is a promising breakthrough for the synthesis of a quasi-heterogeneous catalyst, a bridge between heterogeneous and homogeneous medium. The structure, morphology and physicochemical properties of the material were characterized utilizing various analytical techniques like FT-IR FE-SEM, TEM, VSM, EDX-elemental mapping, ICP, EDX and XPS. The catalyst showed excellent reactivity in C-C and C-N cross coupling reactions via Suzuki and Buchwald-Hartwig reactions respectively. An array of different biphenyls and aryl amines were then procured by reactions of various aryl halides with phenyl boronic acid or secondary amines over the catalyst affording good to excellent yields. The catalyst was easily recoverable using an external magnet and thereafter recycled for several trials with insignificant palladium leaching or loss in catalytic performance. To investigate the cardiovascular protective activities of catalyst, the MTT assay was done on Human Aortic Endothelial Cells (HAEC), Human Coronary Artery Endothelial Cells (HCAEC), and Human Pulmonary Artery Endothelial Cells (HPAEC) cell lines. Nanocatalyst-treated cell cutlers significantly (p <= 0.01) decreased the caspase-3 activity, and DNA fragmentation. It raised the cell viability and mitochondrial membrane potential in the high concentration of Mitoxantrone-treated HAEC, HCAEC, and HPAEC cells. According to the above findings, nanocatalyst can be administrated as a cardiovascular protective drug for the treatment of cardiovascular diseases after approving in the clinical trial studies in humans. (C) 2020 Published by Elsevier B.V

Generation and Validation of a Shewanella oneidensis MR-1 Clone Set for Protein Expression and Phage Display

A comprehensive gene collection for S. oneidensis was constructed using the lambda recombinase (Gateway) cloning system. A total of 3584 individual ORFs (85%) have been successfully cloned into the entry plasmids. To validate the use of the clone set, three sets of ORFs were examined within three different destination vectors constructed in this study. Success rates for heterologous protein expression of S. oneidensis His- or His/GST- tagged proteins in E. coli were approximately 70%. The ArcA and NarP transcription factor proteins were tested in an in vitro binding assay to demonstrate that functional proteins can be successfully produced using the clone set. Further functional validation of the clone set was obtained from phage display experiments in which a phage encoding thioredoxin was successfully isolated from a pool of 80 different clones after three rounds of biopanning using immobilized anti-thioredoxin antibody as a target. This clone set complements existing genomic (e.g., whole-genome microarray) and other proteomic tools (e.g., mass spectrometry-based proteomic analysis), and facilitates a wide variety of integrated studies, including protein expression, purification, and functional analyses of proteins both in vivo and in vitro

Magnetic solid-phase extraction technique based on Fe3O4@coPPy-PTH nanocomposite for extraction of cobalt, chromium, and nickel prior to determination by microsample injection system-flame atomic absorption spectrometry in alcoholic and nonalcoholic beverages

A novel Fe3O4@coPPy-PTH nanocomposite-based sorbent was prepared via in situ oxidative polymerization using Fe3O4 nanoparticles with spherical and flower-like morphologies of thiophene and pyrrole as the feedstocks. The synthesized nanocomposite displayed sensitive extraction and determination of metal ions Co(II), Cr(III), and Ni(II) without a chelating agent, followed by microsample injection system-flame atomic absorption spectrometry. Advanced spectroscopic and imaging techniques including scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy were used to characterize the composition and morphology of the Fe3O4@coPPy-PTH nanocomposite. SEM observations showed that the size of the Fe3O4 nanoparticles changed from 30 nm to 120 nm in diameter after copolymer (PPy-PTH) coating. The Fe3O4@coPPy-PTH nanocomposite has good dispersion properties and stability in strong acid solutions. For effective extraction of the studied analytes, the influence of sample pH, volume of sample solution and eluent, amount of adsorbent, and interference of coexisting metal ions were optimized. Under the optimum conditions, preconcentration factors were obtained as 25 for all analytes. The calibration curves were linear in the range of 0.0–10.0 µg L–1 with coefficients of determination (R2) greater than 0.9957 for all three analytes. Limits of detection (S/N = 3) were calculated in the range of 0.17–0.23 µg L–1. Precision values, expressed as relative standard deviations, were lower than 3.0%, and relative recoveries were obtained in the range of 88.6%–103.6%. The proposed method (Fe3O4@coPPy-PTH/MSPE/MIS-FAAS) was successfully applied to extract and determine the studied metal ions in beer, wine, and nonalcoholic beverage samples. © 2024 TUBITAK. All rights reserved

The impact of inflation on the financial sector development: Empirical evidence from Jordan

In any economy, the financial sector plays a fundamentally important role in achieving economic growth and thus achieving sustainable economic development. Therefore, interest in this sector and the improvement of its performance is considered a strategic goal for any country. Accordingly, this study aims to analyze the short- and long-run impacts of inflation on the development of this sector on the Jordanian economy for the period from 1993 to 2018. To do so, the study uses an auto-regressive distributed lag bound testing approach, which is considered an advanced analytical model. Empirical findings confirmed that there is a statistically significant long- and short-run negative effect of inflation on financial sector development. On the contrary, there is a statistical significant long- and short-run positive impact of economic growth on financial sector performance. In addition, results confirmed that there is a positive support of the previous financial sector policies on financial sector performance in the current period

Physico-Chemical Characterization of Amylose and Amylopectin Using Revan Topological Indices

Polysaccharides are biomaterial with great biocompatibility, biodegradability, and low toxicity. There are long chains of monosaccharide units linked together by glycosidic bonds. They have a wide spectrum of functional properties and are essential to life’s survival. These are a makeup of storage polysaccharides (such as starch and glycogen). Starch is found in plants; the condensation of amylose and amylopectin produces starch. The main contribution of this paper is to compute Revan topological indices of Amylose and Amylopectin that can study their physicochemical characterization. Furthermore, an analysis was being carried out among topological indices to find out compatibility. These indices will be applicable in various useful research aspects

A Visual Analytics System for Supporting Rock Art Knowledge Discovery

This paper presents a visual analytics system, named DARK, for supporting rock art archaeologists in exploring repositories of rock art scenes each consisting of hundreds of petroglyphs carved by ancient people on rocks. With their increasing complexity, analyzing these repositories of heterogeneous information has become a major task and challenge for rock art archaeologists. DARK combines visualization techniques with fuzzy-based analysis of rock art scenes to infer information crucial for the correct interpretation of the scenes. Moreover, the DARK views allow archaeologists to validate their hypothesis against the information stored in the repository

Rheology of colloidal particles in lyotropic hexagonal liquid crystals: the role of particle loading, shape, and phase transition kinetics

The rheology of self-assembled elongated iron oxyhydroxide (FeOOH) and spherical silica (SiO2) particles in hexagonal (H1) liquid crystal (LC) phase of water and non-ionic surfactant C12E9 is investigated by varying particle concentration and cooling rate. The rheology data shows that both SiO2/H1 and FeOOH/ H1 LC composites exhibit a higher G′ when compared to the particle-free H1 phase, with increasing particle loading and cooling rate. FeOOH particles improve G′ of the H1 phase more significantly than SiO2 particles due to the formation of an interconnected network at H1 domain boundaries at cooling rates of 1 and 2 ∘C/min. We hypothesize that self-assembly of particles at domain boundaries leads to a decreased mobility of defects causing an increase in elasticity of particle-laden H1 phase. Dynamic strain sweep and creep experiments show a non-linear stress–strain relationship attributed to the alignment of micellar cylindrical rods under shear.by Siddharth Kulkarni and Prachi Tharej