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61.
The ellagitannin colonic metabolite urolithin D selectively inhibits EphA2 phosphorylation in prostate cancer cells
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62.
Iucci L Patrignani F Belletti N Ndagijimana M Elisabetta Guerzoni M Gardini F Lanciotti R 《Meat science》2007,75(4):669-675
The aim was to study the effects of Debaryomyces hansenii and Yarrowia lipolytica strains, used with lactic acid starter cultures (Lactobacillus plantarum), in the manufacture of dried fermented sausages in order to understand their effects on volatile profile, biogenic amine content and sensory properties. The experimental data showed that every yeast strain produced a specific profile of volatile metabolic products. The yeasts also gave sausages with distinctive sensory properties. The degree of mincing also influenced these properties, but none of these factors had significant influence upon the accumulation of biogenic amines. 相似文献
63.
Luigi Angiolini Tiziana Benelli Loris Giorgini Francesco Mauriello Elisabetta Salatelli 《Reactive and Functional Polymers》2009,69(12):898-904
Novel optically active methacrylic copolymers, bearing carbazole and azoaromatic moieties linked to the main chain with a rigid (S)-hydroxysuccinimide residue of one prevailing absolute configuration, have been prepared and characterized with the aim to establish the effects of the chiral group and of the dipolar interactions between the two side-chain chromophores on their properties.In particular, the observed chiroptical properties suggest the presence of ordered chiral conformations at least for chain segments of the macromolecules. Spectroscopic, thermal and chiroptical characterizations of these copolymers demonstrate the occurrence of significant electronic interactions between carbazole chromophores and azobenzene moieties. These interactions are related to the unusual partially alternating structure of the investigated copolymers and the relevant chiroptical and thermal properties. In fact, the polymeric derivates show high glass transition temperatures and good thermal stability, thus opening the way to a variety of potential applications based on photoconductive and optoelectronic properties. 相似文献
64.
Abstract: This paper considers the main developments of RGB photoelasticity with reference to the maximum measurable retardation. In this paper, a new procedure based on the standard error function evaluated on a subset of the calibration array is also proposed and experimentally tested. The experiments show that the filament lamp makes it possible to find retardations until approximately 4 fringe orders while the fluorescent lamp makes it possible to determine higher fringe orders (12 fringe orders in this paper) owing to the discrete spectrum of the source. The paper shows that, by using the incandescent lamp, the primary limiting factor is the lack of modulation of the R, G and B signals whereas, by using the fluorescent lamp, the limitation of the maximum fringe order derives mainly from the gradient of the fringes and the procedure of search of the retardation. 相似文献
65.
Luca Giorleo Elisabetta Ceretti Claudio Giardini 《The International Journal of Advanced Manufacturing Technology》2013,69(9-12):1961-1969
Circular laser hardening is the laser surface treatment used in the case of cylindrical workpieces. The single-track treatment is a particular case of circular laser hardening used when only one revolution of the workpiece is executed since the treatment of a narrow surface is required. As a result, an annular narrow hardening track is obtained. During the laser hardening, the initial and final parts of the workpiece are overlapped and treated twice. The main drawback of this treatment is the back-tempering effect focused on the overlapping zone. This phenomenon leads to a hardness decrease in the overlapping zone. To avoid this problem, a new technique called apparent spot (AS) was introduced by the authors. The aim of the AS technique is to increase in a fictitious way the dimensions of the laser spot. In the case of circular laser hardening, this technique results into a high-speed rotation (up to 1,000 rpm) of the cylindrical workpiece instead of the traditional low speed. So, a uniform hardening zone without overlapping and back tempering is obtained. However, despite these benefits, there is still a lack of knowledge about the physics of this treatment in particular referring to the thermal cycle that affects the workpiece. In order to enhance the knowledge of this technique in this work, the AS was modeled via the FE approach. DEFORM software was used to model the circular laser hardening process. The software was firstly validated by a comparison with experimental results. Once the software reliability was tested, a regression model was estimated to predict the surface temperature within the treatments. Good agreement was found between the prediction model and the numerical results. 相似文献
66.
A Birkhoff interpolation problem is studied. The explicit solution and estimation of remainder is given. The cases of equidistant
and Chebyshev nodes are considered. This problem is of interest in collocation methods of boundary value problem (Costabile
and Napoli in Far East J. Appl. Math. 25(3):289–305, 2006; Costabile and Longo in Applied and Industrial Mathematics in Italy III, 2009, in press). In addition an application to quadrature is given. 相似文献
67.
Fabio Maria Sabbatini Dr. Romano Di Fabio Dr. Mauro Corsi Dr. Paolo Cavanni Dr. Steve M. Bromidge Dr. Yves St‐Denis Dr. Lucilla D'Adamo Dr. Marilisa Rinaldi Dr. Chiara Savoia Dr. Claudia Mundi Dr. Benedetta Perini Dr. Andrew J. Carpenter Dr. Giovanna Dal Forno Dr. Federico Faggioni Dr. Michela Tessari Dr. Francesca Pavone Dr. Alberto Buson Dr. Mario Mattioli Dr. Elisabetta Perdona' Dr. Sergio Melotto Dr. 《ChemMedChem》2010,5(9):1450-1455
68.
In the random utility modelling context, choice probabilities are unaffected by increasing linear transformations of the systematic
utility; hence its empirical specification is derived on the basis that only differences in utility matters and that the scale
of utility is arbitrary. We argue that choice probabilities remain unchanged if these linear transformations are made under
the deterministic perspective of a single individual choosing several times. But, in the random utility setting, parameter
estimates might be significantly affected by these transformations. In particular we focus on the effect of two order-preserving
transformations usually applied in the derivation of the representative utility from the conditional indirect utility function:
adding a constant to the utility of all alternatives and multiplying each alternative utility by a constant. We concentrate
on the two most popular specifications in transport mode choice: the “wage rate” (Train and McFadden Transport Res 12:349–353,
1978) and the “expenditure rate” (Jara-Díaz and Farah Transport Res 22B:159–171, 1987) specifications. Using a collection of synthetic datasets generated in a new fashion directly from the conditional indirect
utility function, i.e. before applying any expansion or transformation, we demonstrate how taking this class of order-preserving
transformations could lead to misinterpretation of the econometric results, such as detecting randomly distributed and correlated
parameters and/or income and time effects which are in fact not present. 相似文献
69.
Manuela Costanzo Elisabetta Esposito Maddalena Sguizzato Maria Assunta Lacavalla Markus Drechsler Giuseppe Valacchi Carlo Zancanaro Manuela Malatesta 《International journal of molecular sciences》2021,22(10)
In this pilot study, ethosomes and transethosomes were investigated as potential delivery systems for cholecalciferol (vitamin D3), whose deficiency has been correlated to many disorders such as dermatological diseases, systemic infections, cancer and sarcopenia. A formulative study on the influence of pharmaceutically acceptable ionic and non-ionic surfactants allowed the preparation of different transethosomes. In vitro cytotoxicity was evaluated in different cell types representative of epithelial, connective and muscle tissue. Then, the selected nanocarriers were further investigated at light and transmission electron microscopy to evaluate their uptake and intracellular fate. Both ethosomes and transethosomes proven to have physicochemical properties optimal for transdermal penetration and efficient vitamin D3 loading; moreover, nanocarriers were easily internalized by all cell types, although they followed distinct intracellular fates: ethosomes persisted for long times inside the cytoplasm, without inducing subcellular alteration, while transethosomes underwent rapid degradation giving rise to an intracellular accumulation of lipids. These basic results provide a solid scientific background to in vivo investigations aimed at exploring the efficacy of vitamin D3 transdermal administration in different experimental and pathological conditions. 相似文献
70.
J Laut D Senitzer R Petrucci LB Sablay P Barland D Glicklich 《Canadian Metallurgical Quarterly》1992,38(4):179-184
Soluble interleukin-2 receptor (IL-2R) levels were measured and correlated prospectively with clinical, histologic and serologic findings over a 9-month period in 62 lupus patients. Initially, 39 patients had clinical nephritis and 23 patients did not have nephritis. The 62 lupus patients has significantly higher IL-2R than 15 normal controls, most of this difference attributable to patients with nephritis. During lupus nephritis flare 9 of 10 patients showed significant elevations of IL-2R while only 6 of the 10 patients showed either elevation of anti-DNA antibody or decrease in CH50. During disease remission or stable clinical activity changes in IL-2R levels paralleled changes in anti-DNA antibody and CH50. Nephritis patients with cellular proliferative histology had significantly higher IL-2R levels than those with membranous or mesangial nephropathy. IL-2R correlated strongly with histologic activity and chronicity indices, IgG and C3 deposition whereas anti-DNA antibody and CH50 levels did not. IL-2R levels did not correlate with serum creatinine suggesting that elevations of IL-2R were not simply due to decreased clearance. These observations suggest that serum IL-2R level is a useful marker of disease activity in lupus nephritis and may serve as a helpful adjunct in management of this disorder. 相似文献