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161.
Giovanni Gallavotti 《Journal of statistical physics》2014,157(4-5):743-754
Application of asymptotic freedom to the ultraviolet stability in Euclidean quantum field theories is revisited and illustrated through the hierarchical model making also use of a few technical developments that followed the original works of Wilson on the renormalization group. 相似文献
162.
Elena Molteni Giovanni Onida Giancarlo Cappellini 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(4):98
We study the electronic properties of the Si(001):Uracil, Si(001):Thymine, andSi(001):5-Fluorouracil systems, focusing on the Si dimer-bridging configuration withadsorption governed by carbonyl groups. While the overall structural and electronicproperties are similar, with small differences due to chemical substitutions, much largereffects on the surface band dispersion and bandgap show up as a function of the molecularorientation with respect to the surface. An off-normal orientation of the molecular planesis favored, showing larger bandgap and lower total energy than the upright position. Wealso analyze the localization of gap-edge occupied and unoccupied surface states. 相似文献
163.
Giovanni Stracquadanio Elisa Pappalardo Panos M. Pardalos 《Journal of Optimization Theory and Applications》2012,155(3):1008-1024
The design of circular antenna arrays is a challenging optimization problem, which requires ad-hoc methods to fulfill the engineering requirements. In this work, we introduce the Mesh Adaptive Basin Hopping algorithm to tackle such problem effectively; the experimental results show that the new approach proposed outperforms the state-of-the-art methods, both in terms of quality of the solutions and computational efficiency. 相似文献
164.
Giovanni Papandrea 《合成通讯》2013,43(6):858-865
This article describes a new route to peptidosulfonamide. Our study shows how sulfinamides were first obtained via nucleophilic cleavage of 3,6‐dihydrothiazine‐1‐oxide system and how the products can be subjected to oxidation with m‐chloroperbenzoic acid to give sulfonamides in good yield. 相似文献
165.
Giovanni Alessandrini 《Journal of Mathematical Analysis and Applications》2012,386(2):669-676
We prove that solutions to elliptic equations in two variables in divergence form, possibly non-self-adjoint and with lower order terms, satisfy the strong unique continuation property. 相似文献
166.
Lisa Giachini Giulia Veronesi Francesco Francia Giovanni Venturoli Federico Boscherini 《Journal of synchrotron radiation》2010,17(1):41-52
In the present work a data analysis approach, based on XAFS data, is proposed for the identification of most probable binding motifs of unknown mononuclear zinc sites in metalloproteins. This approach combines multiple‐scattering EXAFS analysis performed within the rigid‐body refinement scheme, non‐muffin‐tin ab initio XANES simulations, average structural information on amino acids and metal binding clusters provided by the Protein Data Bank, and Debye–Waller factor calculations based on density functional theory. The efficiency of the method is tested by using three reference zinc proteins for which the local structure around the metal is already known from protein crystallography. To show the applicability of the present analysis to structures not deposited in the Protein Data Bank, the XAFS spectra of six mononuclear zinc binding sites present in diverse membrane proteins, for which we have previously proposed the coordinating amino acids by applying a similar approach, is also reported. By comparing the Zn K‐edge XAFS features exhibited by these proteins with those pertaining to the reference structures, key spectral characteristics, related to specific binding motifs, are observed. These case studies exemplify the combined data analysis proposed and further support its validity. 相似文献
167.
Fabio Mazzotti Leonardo Di Donna Hicham Benabdelkamel Bartolo Gabriele Anna Napoli Giovanni Sindona 《Journal of mass spectrometry : JMS》2010,45(4):358-363
Pterostilbene (trans‐3,5‐dimethoxy‐4‐hydroxystilbene) is an active component found in several plant species, exhibiting important pharmacological properties. A new and reliable method of assaying this phyto compound in various matrices is presented; the assay is based on (1) the selectivity of liquid chromatography (LC) hyphenated with electrospray ionisation (ESI), (2) the specificity of a two‐step mass spectrometric analysis (MS/MS) and (3) the accuracy of the isotope dilution method. The labelled analogue may be conveniently synthesised in a few steps. The sensitivity of the method is confirmed by the very low limit of detection (LOD) and limit of quantitation (LOQ) values achieved in the assay of pterostilbene in two distinct fortified matrices, and is further supported by the observed accuracy values. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
168.
Giovanni Cesaroni Kristiaan Kerstens Ignace Van de Woestyne 《The Journal of the Operational Research Society》2017,68(11):1442-1451
The literature on nonparametric frontier technologies lacks a method for the measurement of scale economies in non-convex settings. This paper proposes a general procedure which is based on the minimization of the ray average cost and requires the solution of a single programming problem. Our approach allows for multiple optima to introduce the case of global sub-constant scale economies, and it also permits the estimation of scale economies at a local level. The empirical application investigates the role of replicability and the relationship between global and local indicators. It also points out the managerial implications for companies operating in the Italian public transit industry. 相似文献
169.
Territorial origin of olive oil: representing georeferenced maps of olive oils by NMR profiling
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Raffaele Lamanna Giovanna Imparato Paola Tano Angela Braca Mario D'Ercole Giovanni Ghianni 《Magnetic resonance in chemistry : MRC》2017,55(7):639-647
ABSTRACT Proton NMR profiling is nowadays a consolidated technique for the identification of geographical origin of food samples. The common approach consists in correlating NMR spectra of food samples to their territorial origin by multivariate classification statistical algorithms. In the present work, we illustrate an alternative perspective to exploit territorial information, contained in the NMR spectra, which is based on the implementation of a geographic information system (GIS). Nuclear magnetic resonance spectra are used to build a GIS map permitting the identification of territorial regions having strong similarities in the chemical content of the produced food (terroir units). These terroir units can, in turn, be used as input for labeling samples to be analyzed by traditional classification methods. In this work, we describe the methods and the algorithms that permit to produce GIS maps from NMR profiles and apply the described method to the analysis of the geographical distribution of olive oils in an Italian region. In particular, we analyzed by 1H NMR up to 98 georeferenced olive oil samples produced in the Abruzzo Italian region. By using the first principal component of the NMR variables selected according to the Moran test, we produced a GIS map, in which we identified two regions incidentally corresponding to the provinces of Teramo and Pescara. We then labeled the samples according to the province of provenience and built an LDA model that provides a classification ability up to 99% . A comparison between the variables selected in the geostatistics and classification steps is finally performed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
170.