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The preparation and characterization of electrosynthesized poly(o-phenylenediamine) (PPD) imprinted by glucose (iPPD) is reported as the first case of an electrosynthesized polymer molecularly imprinted by a neutral template. The material is employed as the recognition element of a QCM biomimetic sensor for glucose. Scatchard analysis of the relevant calibration curve offers information on the equilibrium and binding sites involved in glucose detection. XPS comparison of PPD and iPPD supports the occurrence of a templating effect. On this basis, molecular imprinting electropolymerization is proposed as a possible strategy for the preparation of new materials with molecular recognition properties to be applied in biomimetic sensors.  相似文献   
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Planning Support Systems (PSS) are computer-based tools that assist professionals in land use planning activities. Although several researchers acknowledge the importance of such tools in planning practice, PSS use is limited due to their poor fit to users’ needs and expectations as well as to their low usability. This article presents a study carried out in three different countries, namely, Australia, Italy, and Switzerland, aiming at investigating in-depth the current situation regarding the adoption of PSS and identifying factors preventing their wider use, devoting particular attention to the quality of such systems from the point of view of their users. The study also aimed at analyzing planners’ expectations in order to identify relevant features that PSS should provide. The main part of the study consisted of 35 interviews with planning experts. A follow-up focus group with six further participants was also performed. The results confirmed some findings of previous studies but also revealed new insights. This article provides suggestions on how to address the emerging issues, as well as pathways for creating software that can be adopted and used with satisfaction in the planning practice.  相似文献   
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A numerical study on a non-linear hyperbolic diffusion equation is proposed. The Hartree hybrid method combining finite difference techniques with the method of characteristics is used in the presence of discontinuities between initial and boundary conditions. The technique proved to be an useful tool to overcome oscillation problems and spurious solutions in case of strong non-linearities related to both attractive or repulsive interactions between diffusing species. Two different expressions for the diffusion coefficient are used in order to compare our results with the ones obtained in previous studies relying upon the Laplace transform technique and the MacCormack predictor–corrector method. Finally, an analytic approach based on the singular surface theory is proposed to motivate the numerical results and to clarify some controversial aspects concerning the penetration depth of a diffusive front in the presence of interactions.  相似文献   
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White matter hyperintensities (WMHs) in migraine could be related to inflammatory and antioxidant events. The aim of this study is to verify whether migraine patients with WMHs carry a genetic pro-inflammatory/pro-oxidative status. To test this hypothesis, we analyzed lymphotoxin alpha (LTA; rs2071590T and rs2844482G) and superoxide dismutase 1 (SOD1; rs2234694C) and 2 (SOD2; rs4880T) gene polymorphisms (SNPs) in 370 consecutive patients affected by episodic (EM; n = 251) and chronic (CM; n = 119) migraine and in unrelated healthy controls (n = 100). Brain magnetic resonance was available in 183/370 patients. The results obtained show that genotypes and allele frequencies for all tested SNPs did not differ between patients and controls. No association was found between single SNPs or haplotypes and sex, migraine type, cardiovascular risk factors or disorders. Conversely, the LTA rs2071590T (OR = 2.2) and the SOD1 rs2234694C (OR = 4.9) alleles were both associated with WMHs. A four-loci haplotype (TGCT haplotype: rs2071590T/rs2844482G/rs2234694C/rs4880T) was significantly more frequent in migraineurs with WMHs (7 of 38) compared to those without WMHs (4 of 134; OR = 8.7). We may, therefore, conclude by suggesting that that an imbalance between pro-inflammatory/pro-oxidative and antioxidant events in genetically predisposed individuals may influence the development of WMHs.  相似文献   
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We demonstrate for the first time herein that electrospinning of soluble crosslinked polymer particles (microgels) is feasible and that it can be used to obtain micron-sized fibers from these macromolecules. Most notably, the electrospinning approach is found to be successful also in the case of microgels bearing metal nanoclusters, and allows to prepare composite fibers containing a homogeneous dispersion of metal nanoparticles without alterations in the nanoparticle size and size distribution. Given the broad applicability of microgels as exotemplates and stabilisers for inorganic nanoparticles, the proposed preparation method stands out as a novel, general approach for the synthesis of potentially useful composite fibers containing inorganic nanoparticles.  相似文献   
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Patulin is a mycotoxin produced by certain species of Penicillium and Aspergillus, often detectable in mouldy fruits and their derivatives. On the basis of a PMTDI of 0.4 mu g/kg bw, limit values of 50 mu g/kg or 50 mu g/l of patulin have been set in fruit derivatives. To estimate the quantity of patulin that can be taken in with the diet, we analysed by HPL C samples of apples and apple derivatives which are most likely to be contaminated with patulin. In apple juices and in homogenized babyfoods, the mycotoxin concentration was always below the established limits, while in some samples of juice with pulp the mycotoxin content exceeded the safe levels. In rotten apples, not only was the amount of patulin extraordinarily high in the rotten area, but the mycotoxin had also spread to the part unaffected by mould. The data presented in this study indicate that the intake of patulin with apple derivatives is usually below the tolerable level of 0.4 mu g/kg bw/day, but since the patulin content in apples can vary considerably, the quality of fruits used in the production of apple derivatives should be strictly controlled in order not to exceed the safe limits.  相似文献   
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