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91.
Several frozen vessels bearing atherosclerotic lesion were analysed by cluster TOF-SIMS (time-of-flight secondary ion mass spectrometry) to map their lipid (fatty acids, cholesterol, vitamin E, phosphatidic acids, phosphatidylinositols and triglycerides) content at a micrometric resolution.  相似文献   
92.
High-performance regenerated silkworm (Bombyx mori) silk fibers can be produced efficiently through the straining flow spinning (SFS) technique. In addition to an enhanced biocompatibility that results from the removal of contaminants during the processing of the material, regenerated silk fibers may be functionalized conveniently by using a range of different strategies. In this work, the possibility of implementing various functionalization techniques is explored, including the production of fluorescent fibers that may be tracked when implanted, the combination of the fibers with enzymes to yield fibers with catalytic properties, and the functionalization of the fibers with cell-adhesion motifs to modulate the adherence of different cell lineages to the material. When considered globally, all these techniques are a strong indication not only of the high versatility offered by the functionalization of regenerated fibers in terms of the different chemistries that can be employed, but also on the wide range of applications that can be covered with these functionalized fibers.  相似文献   
93.
Journal of Solid State Electrochemistry - Due to their widespread use in veterinary medicine, the presence of tetracyclines (TCs) and their metabolites in foodstuffs from treated animal represents...  相似文献   
94.
Estimates suggest that more than 70% of the world’s rangelands are degraded. The Normalized Difference Vegetation Index (NDVI) is commonly used by ecologists and agriculturalists to monitor vegetation and contribute to more sustainable rangeland management. This paper aims to explore the scaling character of NDVI and NDVI anomaly (NDVIa) time series by applying three fractal analyses: generalized structure function (GSF), multifractal detrended fluctuation analysis (MF-DFA), and Hurst index (HI). The study was conducted in four study areas in Southeastern Spain. Results suggest a multifractal character influenced by different land uses and spatial diversity. MF-DFA indicated an antipersistent character in study areas, while GSF and HI results indicated a persistent character. Different behaviors of generalized Hurst and scaling exponents were found between herbaceous and tree dominated areas. MF-DFA and surrogate and shuffle series allow us to study multifractal sources, reflecting the importance of long-range correlations in these areas. Two types of long-range correlation appear to be in place due to short-term memory reflecting seasonality and longer-term memory based on a time scale of a year or longer. The comparison of these series also provides us with a differentiating profile to distinguish among our four study areas that can improve land use and risk management in arid rangelands.  相似文献   
95.
In recent decades, pathological consumption has become a growing behavioral misbehavior. Impulsive consumption is governed by two internal behavioral mechanisms that respond fundamentally to the hedonism or Pascal effect and to the emulation or Veblen effect. Today's development of technology acts as a catalyst of consumption by increasing access and availability to products, as well as the advertisement impact. This paper presents a compartmental discrete matrix mathematical model that allows short-term estimates of ordinary, impulsive, and pathological buyers in Spain in three different economic scenarios. The results show that impulsive and pathological buyers will increase in all the economic scenarios. Notable differences in the number of ordinary buyers are found for the group aged over 65 years.  相似文献   
96.
A novel dual electrochemical immunosensor for the multiplexed determination of adrenocorticotropin (ACTH) and cortisol is reported. Aminophenylboronic acid‐modified dual screen‐printed carbon electrodes were prepared on which the corresponding ACTH and cortisol antibodies were immobilized. Competitive immunoassays involved biotinylated ACTH and alkaline phosphatase labelled streptavidin, or alkaline phosphatase labelled cortisol. Differential pulse voltammetry upon 1‐naphtyl phosphate addition was employed to monitor the affinity reactions. The ranges of linearity were 5.0×10?5?0.1 and 0.1?500 ng/mL for ACTH and cortisol. The usefulness of the dual immunosensor was demonstrated by analyzing certified human serum samples with good recoveries.  相似文献   
97.
The nature of a jet’s fragmentation in heavy-ion collisions has the potential to cast light on the mechanism of jet quenching. However, the presence of the huge underlying event complicates the reconstruction of the jet fragmentation function as a function of the momentum fraction z of hadrons in the jet. Here we propose the use of moments of the fragmentation function. These quantities appear to be as sensitive to quenching modifications as the fragmentation function directly in z. We show that they are amenable to background subtraction using the same jet-area-based techniques proposed in the past for jet p t ’s. Furthermore, complications due to correlations between background-fluctuation contributions to the jet’s p t and to its particle content are easily corrected for.  相似文献   
98.
Cysteamine core polyamidoamine G-4 dendron branched with β-cyclodextrins was chemisorbed on the surface of Au electrodes and further coated with Pt nanoparticles. Adamantane-modified glucose oxidase was subsequently immobilized on the nanostructured electrode surface by supramolecular association. This enzyme electrode was used to construct a reagentless amperometric biosensor for glucose, making use of the electrochemical oxidation of H2O2 generated in the enzyme reaction. The amperometric response of the biosensor was rapid (6 s) and a linear function of glucose concentration between 5 and 705 μmol?L?1. The biosensor had a low detection limit of 2.0 μmol?L?1, sensitivity of 197 mA?mol?1?L?cm?2, and retained 94 % of its initial response after storage for nine days at 4 °C.  相似文献   
99.
Reaction of 2-pyridine N-4 ethylthiosemicarbazone, HAm4E, with AgNO3 leads to the hexanuclear compound [Ag(E124tazt)]6 (1) (HE124tazt = 4-ethyl-5-pyridin-2-yl-2,4-dihydro-[1,2,4]triazol-3-thione), the result of an oxidative cyclization of the starting thiosemicarbazone. All Ag atoms of [Ag(E124tazt)]6 are bridged through the six S atoms of the deprotonated E124tazt ligand to form two bridged Ag3S3 rings. Each silver atom exhibits a trigonal planar coordination geometry bonded to two thiolate S atoms and one N atom from the bidentate E124tazt ligand. The AgAg distances are much shorter than the van der Waals’ radius sum for silver(I), suggesting binding interactions between the silver atoms, which were confirmed by means of DFT calculations. The X-ray single-crystal structural analysis reveals the arrangement of 1 as a two-dimensional (2D) network via π–π stacking interactions. Preliminary luminescence measurements have been carried out.  相似文献   
100.
Reactions of N-(6-amino-3-methyl-5-nitroso-4-oxo-3,4-dihydropyrimidin-2-yl)glycine with NIII and CdII ions in 1:1 and 1:4 metal:ligand ratios, in aqueous media at 35°C and 0.1m KCl ionic strength, were studied by potentiometric methods to determine the complex species equilibria formation and their formation constants.Solid complex species from MII/ligand systems (MII=FeII, CoII, CdII and HgII) in aqueous media were isolated and characterized by analytical data, spectroscopic methods (i.r.,1 H-n.m.r., 13C-n.m.r. and electronic), and thermal and magnetic measurements.  相似文献   
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