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101.
Giardina E Stocchi L Foti Cuzzola V Zampatti S Gambardella S Patrizi MP Bramanti P Pirazzoli A Novelli G 《Electrophoresis》2010,31(21):3525-3530
Abacavir (ABC) is an antiretroviral drug highly effective in the treatment of HIV, but its intake can cause severe hypersensitivity reaction (HSR). A strong association between HLA-B(*)57:01 and ABC HSRs was reported by several studies, which demonstrated that HLA-B(*)57:01 screening had a 100% negative predictive value and that it could accurately identify patients at high risk of ABC HSRs. We propose a new sequence-specific primer PCR assay based on fluorescence detection through CE which is highly sensitive, allowing the use of non-infective sources of DNA such as saliva and buccal swabs, in addition to blood and reproducible, allowing automation of the analytical process. The results of our study were first compared with a standard sequence-specific primer PCR technique and reported a concordance of 100%, and then a blind external validation further confirmed the accuracy of our method. 相似文献
102.
Muhammad H. Asghar Muhammad Shoaib Frank Placido Shahzad Naseem 《Central European Journal of Physics》2008,6(4):853-863
Complex multilayer thin film filters for optical applications have been designed, prepared and characterized in this work.
E-beam reactive evaporation technique has been used as a deposition process. In the first stage, optimized individual film
layers of TiO2, Ta2O5, and SiO2 are deposited and characterized optically and structurally before the deposition of multilayered structures. The filter designs
are based upon 33 layered SiO2/TiO2 and SiO2/Ta2O5 configurations on glass substrate. These designs are optimized to achieve wideband transmission in the visible spectrum.
After deposition, the two filter configurations are characterized optically and structurally using spectrophotometery, atomic
force microscopy (AFM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). SiO2/Ta2O5/glass filter has been found sensitive to deposition conditions since high absorption is observed in multilayered configuration
for the as-deposited samples. Post-deposition annealing of the filter in the temperature range 150 to 250°C was also performed
in order to study the effect of temperature on absorption and spectral characteristics of the filter. Comparison of the two
filter configurations was also performed to analyze their suitability for optical applications. Adhesion of the two filters
was found to be very good by means of tape-peel test.
相似文献
103.
Placido Cicala 《Meccanica》1971,6(1):59-64
Summary Generalization of Vlasof's theory to non-shallow shells referred to an arbitrary coordinate system. A discretization procedure is suggested, with quadrilateral finite elements where the relevant magnitudes are expressed by finite differences.
Sommario La teoria di Vlasof è estesa al guscio di curvatura rilevante con riferimento ad un sistema generico di coordinate. È proposto un metodo di discretizzazione nel quale si suddivide la parete in elementi quadrilateri dove le quantità in gioco vengono espresse per differenze finite.相似文献
104.
Placido Cicala 《Meccanica》1981,16(2):85-92
Summary Through the asymptotic approach to elastic theory of beam-like structural elements, various categories of problems are distinguished with different first approximation formulations, showing different degrees of non-linearity.
Sommario Per la teoria elastica di elementi strutturali tipo trave, il metodo asintotico porta a individuare varie categorie di problemi, retti da diverse formulazioni con diversi gradi di non-linearità, qui considerate in forma di prima approssimazione. Il metodo, oltre a fornire giustificazione di formulazioni classiche, offre la possibilità di approfondimenti sistematici.相似文献
105.
Beatrice Campanella Massimo Onor Carlo Ferrari Alessandro D’Ulivo Emilia Bramanti 《Analytica chimica acta》2014
In this work we have studied the derivatization of protein disulfide bonds with p-Hydroxymercurybenzoate (pHMB) in strong alkaline medium without any preliminary reduction. The reaction has been followed by the determination of the protein–pHMB complex using size exclusion chromatography coupled to a microwave/UV mercury oxidation system for the on-line oxidation of free and protein-complexed pHMB and atomic fluorescence spectrometry (SEC–CVG–AFS) detection. The reaction has been optimized by an experimental design using lysozyme as a model protein and applied to several thiolic proteins. 相似文献
106.
Beatrice Campanella Massimo Onor Marco Carlo Mascherpa Alessandro D’Ulivo Carlo Ferrari Emilia Bramanti 《Analytica chimica acta》2013
We developed a flow injection (FI) method for the determination of thiomersal (sodium ethylmercurithiosalicylate, C9H9HgNaO2S) based on the UV/microwave (MW) photochemical, online oxidation of organic mercury, followed by cold vapor generation atomic fluorescence spectrometry (CVG-AFS) detection. Thiomersal was quantitatively converted in the MW/UV process to Hg(II), with a yield of 97 ± 3%. This reaction was followed by the reduction of Hg(II) to Hg(0) performed in a knotted reaction coil with NaBH4 solution, and AFS detection in an Ar/H2 miniaturized flame. The method was linear in the 0.01–2 μg mL−1 range, with a LOD of 0.003 μg mL−1. This method has been applied to the determination of thiomersal in ophthalmic solutions, with recoveries ranging between 97% and 101%. We found a mercury concentration in commercial ophthalmic solutions ranging between 7.5 and 59.0 μg mL−1. 相似文献
107.
Li-Jian Meng V. Teixeira Frank Placido M.P. dos Santos 《Applied Surface Science》2006,252(22):7970-7974
TiO2 thin films were deposited on the glass substrates by dc reactive magnetron sputtering technique at different sputtering pressures (2 × 10−3 to 2 × 10−2 mbar). The films prepared at low pressures have an anatase phase, and the films prepared at high pressures have an amorphous phase. The optical properties were studied by measuring the transmittance and the ellipsometric spectra. The optical constants of the films in the visible range were obtained by fitting the transmittance combined with the ellipsometry measurements using the classical model with one oscillator. The refractive index of the films decreases from 2.5 until 2.1 as the sputtering pressure increases from 2 × 10−3 to 2 × 10−2 mbar. The films prepared at the pressure higher than 6 × 10−3 mbar show a volume inhomogeneity. This volume inhomogeneity has been calculated by fitting the transmittance and the ellipsometric spectra. The volume inhomogeneity of the film prepared at the highest sputtering pressure is about 10%. Although the films prepared at high pressures show a large volume inhomogeneity, they have low extinction coefficients. It is suggested that the anatase phase results in more light scattering than amorphous phase does, and then a high extinction coefficient. 相似文献
108.
Pompa PP Della Torre A del Mercato LL Chiuri R Bramanti A Calabi F Maruccio G Cingolani R Rinaldi R 《The Journal of chemical physics》2006,125(2):21103
Electrical conduction in solid state disordered multilayers of non-redox proteins is demonstrated by two-terminal transport experiments at the nanoscale and by scanning tunneling microscopy (STM/STS experiments). We also show that the conduction of the biomolecular films can be modulated by means of a gate field. These results may lead to the implementation of protein-based three-terminal nanodevices and open important new perspectives for a wide range of bioelectronic/biosensing applications. 相似文献
109.
The first examples of alkali metal cation conformational templation of a calix[7]arene derivative were found in the alkali salts of 1,4-calix[7]crown-4, which were obtained by its treatment with the corresponding alkali metal carbonates. Competitive experiments showed that potassium and rubidium cations give the most effective templation, with a slight preference for the former. Experimental results and Monte Carlo conformational searches indicated that the cation interacts with all O-atoms including those of the crown-4 bridge. 相似文献
110.
Maria C. Aversa Placido Giannetto Giovanni Romeo Paola Ficarra Maria G. Vigorita 《Journal of heterocyclic chemistry》1980,17(3):551-554
The stereochemistry of some 1-methyl-5-phenyl-2,3,4,5-tetrahydro-1H-1,5-benzodiazepine-2,4-diones was determined by proton magnetic resonance using the paramagnetic shift reagent tris(6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionato)europium [Eu(fod)3] two of these compounds, clobazam and triflubazam, are clinically used as psychotherapeutic agents. Several model structures, with intermediate stereochemistry in the range of the possible limit situations of benzocycloheptene, -cycloheptadiene or -cycloheptatriene type, are considered; LIS (3) are computer simulated on the basis of proton geometric parameters. It was found that at room temperature, these derivatives exist in only one pseudo-boat cycloheptadiene-like conformation, showing the 5-phenyl group directed pseudo-axially. This conformational preference is interpreted in terms of a balance between the steric requirements of the bulky substituent and electronic repulsion in the ring π-system. 相似文献