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41.
42.
This paper reports a study on the influence of calcination pretreatments on the catalytic behaviour of the Au/iron oxide system towards the combustion of some representative volatile organic compounds (2-propanol, ethanol, methanol, acetone and toluene). The catalytic activity of Au/Fe2O3 samples towards the total oxidation to CO2 has been found to be strongly dependent on the catalyst pretreatment, decreasing on increasing the calcination temperature. On the basis of characterisation data (XPS, FT-IR, XRD, BET surface area) it has been proposed that the catalytic behaviour is related to the gold state and/or the iron oxide phase. It appears plausible to suggest that the gold oxidation state and/or the particle size play a key role in the catalytic combustion of volatile organic compounds.  相似文献   
43.
Platinum(II) complexes of the type [Pt(Cl)(PPh3){(κ2-N,O)-(1{C(R)=N(OH)-2(O)C6H4})}] with R=Me, H, ( 1 and 2 ) were synthesized and characterized. Single-crystal X-ray diffraction confirmed the proposed (SP4-3) configuration for 1 . Study of the antiproliferative activity, performed on a panel of human tumor cell lines and on mesothelial cells, highlighted complex 2 as the more effective. In particular, it showed a remarkable cytotoxicity in ovarian carcinoma cells (A2780) and interestingly, a significant antiproliferative effect on cisplatin resistant cells (A2780cis). Investigation into the intracellular mechanism of action demonstrated that 2 had a lower ability to platinate DNA than did cisplatin, which was taken as reference, and a notably higher uptake in resistant cells. A significant accumulation in mitochondria, along with the ability to induce concentration-dependent mitochondrial membrane depolarization and intracellular reactive oxygen species production, allowed us to propose a mitochondrion-mediated pathway as responsible for the interesting cytotoxic profile of complex 2 .  相似文献   
44.
Traditional Mediterranean diets, as opposed to North European and American diets, include a significantly large amount of plant foods; this notable difference between the two eating styles, despite the similarities among other classic risk factors for coronary heart disease (CHD) such as high plasma cholesterol levels, has been associated with a lower risk of developing the CHD and certain cancers. The involvement of excessive free radical production and the great number of epidemiologic studies linking antioxidant intake with a reduced incidence of the above-mentioned diseases indicate that dietary antioxidants likely play a protective role. Because diets in the Mediterranean are (or better yet, were) characterized by abundant plant foods (fruits, vegetables, breads, nuts, seeds; wine and olive oil), this article includes a review of the potential activities of dietary antioxidants, which are plentiful in Mediterranean diets, and wine as related to human disease.  相似文献   
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Next-generation sequencing (NGS) is a cost-effective technology capable of screening several genes simultaneously; however, its application in a clinical context requires an established workflow to acquire reliable sequencing results. Here, we report an optimized NGS workflow analyzing 22 lung cancer-related genes to sequence critical samples such as DNA from formalin-fixed paraffin-embedded (FFPE) blocks and circulating free DNA (cfDNA). Snap frozen and matched FFPE gDNA from 12 non-small cell lung cancer (NSCLC) patients, whose gDNA fragmentation status was previously evaluated using a multiplex PCR-based quality control, were successfully sequenced with Ion Torrent PGM™. The robust bioinformatic pipeline allowed us to correctly call both Single Nucleotide Variants (SNVs) and indels with a detection limit of 5%, achieving 100% specificity and 96% sensitivity. This workflow was also validated in 13 FFPE NSCLC biopsies. Furthermore, a specific protocol for low input gDNA capable of producing good sequencing data with high coverage, high uniformity, and a low error rate was also optimized. In conclusion, we demonstrate the feasibility of obtaining gDNA from FFPE samples suitable for NGS by performing appropriate quality controls. The optimized workflow, capable of screening low input gDNA, highlights NGS as a potential tool in the detection, disease monitoring, and treatment of NSCLC.  相似文献   
47.
Quaternized polysulfones with different ionic chlorine content tested for biomedical applications were obtained by quaternization reaction of chloromethylated polysulfones with N,N‐dimethylethanolamine. The relationship between the different physical and chemical characteristics of these polymers and their biocompatible and antimicrobial properties was established for maximizing the selectivity and performance of these materials for biomedical applications. Therefore, topographic reorganization of the polysulfonic films induced by the type of nonsolvent in casting solutions of polymer significantly influences films morphology, depending on the charge density of polyelectrolytes, the hydrophilic/hydrophobic characteristics, as well as on the history of the formed films. Furthermore, the study of the adhesion of red blood cells and cohesion of platelets on the surface of quaternized polysulfone films, as well as analysis of antibacterial activity, using Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923 microorganisms, contribute to extending the possible applications of quaternized polysulfones as semipermeable membranes in biomedical domains. POLYM. ENG. SCI., 55:2184–2194, 2015. © 2015 Society of Plastics Engineers  相似文献   
48.
The passivating effects produced on Ni49Ti51 (at.%) shape memory alloy by electropolishing in methanol-sulphuric acid electrolyte or thermal treatment in air are investigated with ion-beam techniques (secondary ion mass spectrometry (SIMS) and mass resolved ion scattering spectrometry (MARISS)) and electrochemical techniques (polarisation curves, photocurrent spectroscopy and impedance). Electropolishing produces a limited passivation due to formation of a thin layer of amorphous TiO2, which causes only a slight hindrance to the oxygen evolution reaction. Thermal treatment in air at 450 °C causes a more substantial passivation due to formation of a thick oxide layer, estimated at about 80 nm for a 16 h treatment on the basis of weight increase, disregarding roughness. Data indicate that the film produced by thermal oxidation has probably a duplex structure, with a porous outer layer with inclusions of Ni species and a compact inner layer, in contact with the substrate, consisting of (essentially) nickel free TiO2 rutile.  相似文献   
49.
Poly(vinyl alcohol) (PVA) hydrogels were prepared in the presence/absence of Laponite RD (LRD) by using glutaraldehyde (GL) as chemical crosslinker. The effect of GL concentration (CHO/OH ratio between 0.02 and 0.38) and of clay addition on the PVA hydrogel properties was investigated. The swollen hydrogels showed good transparency and flexibility. LRD incorporation into the PVA hydrogel, revealed by Fourier transform infrared spectroscopy, led to a significant increase of the roughness of the dried hydrogel surface (about two times), as established by atomic force microscopy. The swelling ability was affected in a small extent by the clay addition. The elastic modulus decreased from 4680 to 3340 Pa and from 2195 to 1603 Pa by addition of 0.5% LRD into PVA hydrogels obtained with CHO/OH ratio of 0.02 and 0.06, respectively. The LRD addition reduced the gelation time determined by in situ rheological monitoring of PVA crosslinking reaction. The experimental investigations showed that there is an optimum CHO/OH ratio of 0.02 for which the PVA/LRD hybrid hydrogel presents the properties required by a targeted application, as for example support material for wound dressings. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46661.  相似文献   
50.
Conventional expanded polystyrene can absorb moisture, which significantly degrades its properties. In the present study, it was demonstrated that SiO2 can be deposited on polystyrene beads before pre-expansion and molding steps. Under the applied test conditions, expanded polystyrene with nanocrystalline SiO2 additives had approximately 10% lower moisture adsorption and an 8.4% better resistance to deformation. Expanded polystyrene analysis suggested that the observed improvements were caused by the hydrophobic nature of nanocrystalline SiO2 and, even more importantly, because SiO2 acted as an amalgamation catalyst and significantly increased adhesion between the expanded polystyrene beads during the expanded polystyrene molding process.  相似文献   
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