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BACKGROUND: Ferulago setifolia K. Koch (Apiaceae) has been the subject of this study, aiming to comprehensively determine its phenolic fingerprint and evaluate its various biological activities. The liquid chromatography-tandem mass spectrometry analysis of the 70% methanol extract of F. setifolia (FS) revealed the presence of 23 phytochemicals, among which chlorogenic acid, quinic acid, kaempferol-3-O-glucoside, and quercetin-3-O-glucoside were identified as the major phenolics in the extract. RESULTS: The biological screening included examinations of antioxidant, antibacterial, antiproliferative, and cytotoxic activities. The FS extract displayed moderate 2,2-diphenyl-1-picrylhydrazyl radical scavenging and ferric-reducing capacity, indicating moderate antioxidant activity. Furthermore, FS exhibited significant antiproliferative effects on cancer cells while showing low cytotoxicity on normal cells. The antibacterial activity findings revealed that FS demonstrated potent activity against Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus aureus, and Escherichia coli. CONCLUSION: The findings of this study suggest that the methanolic extract of FS holds promise as a potential source of biologically active compounds. It can be utilized for the development of pharmaceutical formulations, thanks to its significant antiproliferative and antibacterial activities. Additionally, FS can serve as a valuable source of chlorogenic acid for industrial applications. © 2023 Society of Chemical Industry.
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Apiaceae , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ácido Clorogênico/farmacologia , Antioxidantes/química , Compostos Fitoquímicos/química , Fenóis/análise , Antibacterianos/farmacologiaRESUMO
Various theoretical and experimental methods are utilized to investigate the thermal conductivity of nanostructured materials; this is a critical parameter to increase performance of thermoelectric devices. Among these methods, equilibrium molecular dynamics (EMD) is an accurate technique to predict lattice thermal conductivity. In this study, by means of systematic EMD simulations, thermal conductivity of bulk Si-Ge structures (pristine, alloy and superlattice) and their nanostructured one dimensional forms with square and circular cross-section geometries (asymmetric and symmetric) are calculated for different crystallographic directions. A comprehensive temperature analysis is evaluated for selected structures as well. The results show that one-dimensional structures are superior candidates in terms of their low lattice thermal conductivity and thermal conductivity tunability by nanostructuring, such as by diameter modulation, interface roughness, periodicity and number of interfaces. We find that thermal conductivity decreases with smaller diameters or cross section areas. Furthermore, interface roughness decreases thermal conductivity with a profound impact. Moreover, we predicted that there is a specific periodicity that gives minimum thermal conductivity in symmetric superlattice structures. The decreasing thermal conductivity is due to the reducing phonon movement in the system due to the effect of the number of interfaces that determine regimes of ballistic and wave transport phenomena. In some nanostructures, such as nanowire superlattices, thermal conductivity of the Si/Ge system can be reduced to nearly twice that of an amorphous silicon thermal conductivity. Additionally, it is found that one crystal orientation, [Formula: see text]100[Formula: see text], is better than the [Formula: see text]111[Formula: see text] crystal orientation in one-dimensional and bulk SiGe systems. Our results clearly point out the importance of lattice thermal conductivity engineering in bulk and nanostructures to produce high-performance thermoelectric materials.
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The isolation of single- to few-layer transition metal dichalcogenides opens new directions in the application of two-dimensional materials to nanoelectronics. The characterization of thermal transport in these new low-dimensional materials is needed for their efficient implementation, either for general overheating issues or specific applications in thermoelectric devices. In this study, the lattice thermal conductivities of single-layer MoS2 and MoSe2 are evaluated using classical molecular dynamics methods. The interactions between atoms are defined by Stillinger-Weber-type empirical potentials that are developed to represent the structural, mechanical, and vibrational properties of the given materials. In the parameterization of the potentials, a stochastic optimization algorithm, namely particle swarm optimization, is utilized. The final parameter sets produce quite consistent results with density functional theory in terms of lattice parameters, bond distances, elastic constants, and vibrational properties of both single-layer MoS2 and MoSe2. The predicted thermal properties of both materials are in very good agreement with earlier first-principles calculations. The discrepancies between the calculations and experimental measurements are most probably caused by the pristine nature of the structures in our simulations.
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We investigated the antioxidant and enzyme inhibitory activities and chemical composition of the hydro-distilled essential oil (0.35% yield) from aerial parts of Thymus spathulifolius. Antioxidant capacity of the oil was assessed by different methods including free radical scavenging (DPPH and ABTS), reducing power (FRAP and CUPRAC) and phosphomolybdenum assay. Inhibitory activities were analyzed against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, α-glucosidase, and tyrosinase. Twenty-one constituents were identified representing 97.2% of the total oil with thymol (50.5%), borneol (16.7%) and carvacrol (7.7%) as the major components. The essential oil exhibited good antioxidant activity with IC50 values of 3.82 and 0.22 mg/mL determined by free radical scavenging DPPH and ABTS, respectively. EC50 values of FRAP and CUPRAC were found to be 0.12 and 0.34 mg/mL, respectively. The results of the present study support the uses of T. spathulifolius essential oil as a source of natural antioxidants and bioactivities for functional foods and phytomedicines.
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Antioxidantes/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Lamiaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Componentes Aéreos da Planta/química , Acetilcolinesterase/metabolismo , Antioxidantes/química , Butirilcolinesterase/metabolismo , Cloretos/química , Cobre/química , Relação Dose-Resposta a Droga , Compostos Férricos/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Oxirredução , Relação Estrutura-Atividade , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismoRESUMO
The aim of this research is to investigate basalt as a natural mineral-based fibre together with a vitrimeric resin as a sustainable alternative to standard composite materials. Vitrimers combine the properties of thermoset and thermoplastic polymers, enabling the repair of specimens and hence prolonging the lifetime of the composite material. The micro-mechanical characteristics between the basalt fibres and the vitrimer resin are reported and shown to match those of a standard Skyflex K51 epoxy resin. Discontinuous (4 mm) basalt fibres were employed to produce aligned discontinuous fibre-reinforced composites (ADFRCs) using the high-performance discontinuous fibre (HiPerDiF) technology. The mechanical characteristics of the laminates were investigated through tensile testing and the fracture zones were analysed under a scanning electron microscope. By normalising the results by their respective fibre volume fraction, it was discovered that the vitrimer-basalt ADFRCs exhibited, on average, a 4% higher strength and a 25% higher stiffness compared to their basalt epoxy counterparts. The repair potential of the vitrimer ADFRC specimens was explored during low-temperature compression repair. Two approaches were tested using double-sided local- and full-patch repair. Both successfully recovered a significant amount of their prime strength. In conclusion, the potential of the sustainable vitrimer-basalt composite is shown by its competitive mechanical performance. Combining this with the manufacturing flexibility, repair potential, and recyclability of the material, the vitrimer-basalt composite seems to be a competitive alternative to standard glass epoxies.
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OBJECTIVE: Parasites and plant seeds may both be found in appendectomy specimens. Each plant seed has a different appearance and can thus exhibit wide variations under the microscope. Fragmented seeds may histologically mimic parasites. The differential diagnosis between seeds and parasites can be challenging in such cases. This study aimed to determine the incidence of parasites, seeds, and foreign bodies in appendectomy materials and highlight the most characteristic histopathological features associated with these structures. MATERIAL AND METHOD: In this study, pathology slides of 9,480 patients, who underwent appendectomy between 2010 and 2021, were reviewed, and cases that contained parasites, seeds, or foreign bodies were identified. We reviewed the literature on seeds and parasites in appendectomy specimens. RESULTS: Parasites were observed in 56 (0.6%) cases. Of these cases, 45 had Enterobius vermicularis (80%), and 11 had Taenia subspecies (20%). Plant seeds were observed in 47 cases (0.5%), and were macroscopically recognizable in 5 of them as olive, lemon, and cherry seeds. Parasites and seeds were usually observed in the lumen of appendix vermiformis, filled with abundant fecal materials. CONCLUSION: Seeds are seen in approximately 0.5% of the appendectomy specimens. Though rarely seen, the fragmented seed appearance may cause diagnostic difficulties. In this context, the key morphological features of parasites and plant seeds outlined in this study may be helpful in their differential diagnosis.
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Apendicite , Apêndice , Enterobíase , Corpos Estranhos , Parasitos , Animais , Humanos , Apêndice/parasitologia , Apêndice/patologia , Apêndice/cirurgia , Apendicite/complicações , Apendicite/epidemiologia , Apendicite/cirurgia , Enterobíase/diagnóstico , Enterobíase/epidemiologia , Enterobíase/parasitologia , Estudos Retrospectivos , Apendicectomia , Corpos Estranhos/complicações , Corpos Estranhos/patologiaRESUMO
Sustainable fibre reinforced polymer composites have drawn significant attention in many industrial sectors as a means for overcoming issues with end-of-life regulations and other environmental concerns. Plant based natural fibres are considered to be the most suitable reinforcement for sustainable composites since they are typically from renewable resources, are cheap, and are biodegradable. In this study, a number of plant based natural fibres-curaua, flax, and jute fibres-are used to reinforce epoxy, poly(lactic acid) (PLA), and polypropylene (PP) matrices to form aligned discontinuous natural fibre reinforced composites (ADNFRC). The novel HiPerDiF (high performance discontinuous fibre) method is used to produce high performance ADNFRC. The tensile mechanical, fracture, and physical (density, porosity, water absorption, and fibre volume fraction) properties of these composites are reported. In terms of stiffness, epoxy and PP ADNFRC exhibit similar properties, but epoxy ADNFRC shows increased strength compared to PP ADNFRC. It was found that PLA ADNFRC had the poorest mechanical performance of the composites tested, due principally to the limits of the polymer matrix. Moreover, curaua, flax (French origin), and jute fibres are found to be promising reinforcements owing to their mechanical performance in epoxy and PP ADNFRC. However, only flax fibre with desirable fibre length is considered to be the best reinforcement constituent for future sustainable ADNFRC studies in terms of mechanical performance and current availability on the market, particularly for the UK and EU.
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The aim of the present study is to determine the potent biological activities and carry out isolation studies on Barbarea integrifolia. The antioxidant capacity of the species was evaluated by total phenolic content, FRAP, CUPRAC, and DPPH radical scavenging activity. Anticancer activity studies were performed by MTT assay in MDA-MB-231, MCF-7, Hep3B, PC-3, A549, HCT116, L-929 cell lines. It was observed that the remaining aqueous fraction has higher total phenolic content while higher activity in the CUPRAC and FRAP assays was displayed for the methanolic extract and chloroform fraction. The extracts showed anticancer activity as compared with vincristine. It was observed that chloroform fraction has the highest anticancer activity on MCF-7 cell line, while ethyl acetate fraction has the highest anticancer activity on Hep-3B and A549 cell lines. Methanolic extract has the highest anticancer activity on HCT116 and MDA-MB-23 cell lines. The isolation studies have been performed using several chromatographic methods. The chemical structures of compounds have been identified by means of 1H NMR, 13C NMR, 2D-NMR, and MS. Five major compounds, one steroid (ß-Sitosterol), one phenolic acid (Rosmarinic acid), one flavonol heteroside (kaempferol 7-O-α-l-rhamnoside-3-O-ß-d-(2-O-ß- d -glucosyl)-ß-d-glucoside), and two glucosinolates (Gluconasturtiin, Gluconasturtiin choline salt) have been isolated.
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Antioxidantes/farmacologia , Barbarea/química , Glucosinolatos/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Extratos Vegetais/química , Espectroscopia de Prótons por Ressonância Magnética/métodosRESUMO
Sonchus erzincanicus (Asteraceae) is an endemic species in Turkey, where six Sonchus species grow. In this study, a phytochemical study was performed on the aerial parts of the plant. The study describes the isolation and structure elucidation of five flavonoids and two a-ionone glycosides from S. erzincanicus. The compounds were isolated using several and repeated chromatographic techniques from ethyl acetate and aqueous phases that were partitioned from a methanol extract obtained from the plant. 5,7,3',4'-Tetrahydroxy-3-methoxyflavone (1) and quercetin 3-O-beta-D-glucoside (2) were isolated from the ethyl acetate phase, while corchoionoside C 6'-O-sulfate (3), corchoionoside C (4), luteolin 7-O-glucuronide (5) and luteolin 7-O-beta-D-glucoside (6), apigenin 7-O-glucuronide (7) were isolated from the aqueous phase. Corchoionoside C 6'-O-sulfate (3), isolated for the first time from a natural source, was a new compound. The structures of the compounds were elucidated by means of 1H-NMR, 13C-NMR, 2D-NMR (COSY, HMQC, HMBC) and ESI-MS.
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Glucosídeos/química , Norisoprenoides/química , Sonchus/química , Ésteres do Ácido Sulfúrico/química , Flavonoides/química , Flavonoides/isolamento & purificação , Glucosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Norisoprenoides/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Ésteres do Ácido Sulfúrico/isolamento & purificaçãoRESUMO
Growing environmental concerns and stringent waste-flow regulations make the development of sustainable composites a current industrial necessity. Natural fibre reinforcements are derived from renewable resources and are both cheap and biodegradable. When they are produced using eco-friendly, low hazard processes, then they can be considered as a sustainable source of fibrous reinforcement. Furthermore, their specific mechanical properties are comparable to commonly used, non-environmentally friendly glass-fibres. In this study, four types of abundant natural fibres (jute, kenaf, curaua, and flax) are investigated as naturally-derived constituents for high performance composites. Physical, thermal, and mechanical properties of the natural fibres are examined to evaluate their suitability as discontinuous reinforcements whilst also generating a database for material selection. Single fibre tensile and microbond tests were performed to obtain stiffness, strength, elongation, and interfacial shear strength of the fibres with an epoxy resin. Moreover, the critical fibre lengths of the natural fibres, which are important for defining the mechanical performances of discontinuous and short fibre composites, were calculated for the purpose of possible processing of highly aligned discontinuous fibres. This study is informative regarding the selection of the type and length of natural fibres for the subsequent production of discontinuous fibre composites.
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The oil obtained by hydrodistillation from the aerial parts of Artemisia incana (L.) Druce from Turkey was analyzed by GC and GC/MS. Sixty-three compounds were characterized, representing 97.2% of the total components detected, and camphor (19.0%), borneol (18.9%), 1,8-cineole (14.5%), bornyl acetate (7.8%), camphene (4.9%), and alpha-thujone (4.8%) were identified as predominant components. The essential oil was also tested for its antimicrobial activity against 44 different foodborne microorganisms, including 26 bacteria, 15 fungi, and 3 yeast species. The essential oil of A. incana exhibited considerable inhibitory effects against all bacteria, fungi, and yeast species tested. However, the oil showed lower inhibitory activity against the tested bacteria than the reference antibiotics.
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Anti-Infecciosos/química , Artemisia/química , Óleos Voláteis/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologiaRESUMO
Using first-principles density functional theory calculations, we investigate adsorption properties and the diffusion mechanism of a Li atom on hydrogenated single-layer α- and ß-silicene on a Ag(111) surface. It is found that a Li atom binds strongly on the surfaces of both α- and ß-silicene, and it forms an ionic bond through the transfer of charge from the adsorbed atom to the surface. The binding energies of a Li atom on these surfaces are very similar. However, the diffusion barrier of a Li atom on H-α-Si is much higher than that on H-ß-Si. The energy surface calculations show that a Li atom does not prefer to bind in the vicinity of the hydrogenated upper-Si atoms. Strong interaction between Li atoms and hydrogenated silicene phases and low diffusion barriers show that α- and ß-silicene are promising platforms for Li-storage applications.
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By performing density functional theory (DFT)-based calculations, the performance of α-silicene as oxidation-resistant coating on Ag(111) surface is investigated. First of all, it is shown that the Ag(111) surface is quite reactive against O atoms and O2 molecules. It is known that when single-layer silicene is formed on the Ag(111) surface, the 3 × 3-reconstructed phase, α-silicene, is the ground state. Our investigation reveals that as a coating layer, α-silicene (i) strongly absorbs single O atoms and (ii) absorbs O2 molecules by breaking the strong O-O bond. (iii) Even the hollow sites, which are found to be most favorable penetration path for oxygens, serves as high-energy oxidation barrier, and (iv) α-silicene becomes more protective and less permeable in the presence of absorbed O atom. It appears that single-layer silicene is a quite promising material for ultra-thin oxidation-protective coating applications.
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BACKGROUND: The present objective was to evaluate effects of acetaminophen and mannitol on renal function and histopathology in crush injuries. METHODS: Thirty-six rats weighing 370-400 g each were used. No surgery was performed on the first (control) group. The gastrocnemius muscle regions of each rat in the remaining 5 groups were compressed for 2 or 24 hours. In the 4th group, 100 mg/kg acetaminophen was intraperitoneally administered. In the 5th group, 1 g/kg mannitol was administered. In the 6th group, 100 mg/kg acetaminophen and 1 g/kg mannitol were administered. RESULTS: No statistically significant differences were observed among the treatment groups in terms of sodium, potassium, alanine aminotransferase (ALT), and average creatinine clearance values. Hydropic degeneration, tubular necrosis, presence of immunoperoxidase and myoglobin, tubulus epithelial cell degeneration, and presence of PAS-dyed material in tubular lumen was more prominently decreased in the acetaminophen group than the mannitol group. Improvement was observed in the group that was administered both drugs, compared to the mannitol-only group, though findings were still worse than those of the group administered acetaminophen only. CONCLUSION: In crush injuries, acetaminophen improves histopathological renal damage better than mannitol. When used in conjunction with mannitol, the toxic effect of acetaminophen on the liver is decreased.