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11.
In this paper we show some new applications of the approximation theory, by means of the multivariate sampling Kantorovich operators, to thermographic images in seismic engineering. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
12.
Sampling series play a crucial role in Signal and Image Processing. In this note, we illustrate a general method to construct Sampling series and to determine their convergence in Orlicz spaces. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
13.
Camilla?Terenzi Cinzia?CasieriEmail author Francesco?De?Luca Raimondo?Quaresima Giovanni?Quarta Valentina?Tudisca 《Applied magnetic resonance》2015,46(10):1159-1178
This study deals with the application of two-dimensional proton nuclear magnetic resonance relaxometry (2D 1H NMR-R) to the characterization of porous ceramics nearly free of magnetic compounds. Different microstructural properties were obtained by firing a diamagnetic mixture of kaolin, calcium, and magnesium carbonate over a wide range of maximum temperatures (600–1100 °C) and firing times at the maximum temperature (soaking times) (0–10 h). The 2D 1H NMR-R method relies on the correlated measurement of 1H longitudinal (T 1) and transverse (T 2) relaxation times of pore-filling water by which the properties of the interconnected pore space may be investigated. In the absence of significant magnetic susceptibility effect due to para- and ferro-magnetic compounds, the 2D 1H NMR-R maps allow studying the conjoint effects on pore size distribution and inter-pore coupling due to the variations in both time and temperature of firing. The NMR experiments were performed with a low-field 1H NMR sensor, which allows non-destructive and in situ analysis. For ceramic specimens fired at 600 and 700 °C, the fraction of smallest pores increases with firing time at the expenses of those with intermediate size. The pore shrinkage occurring at this stage, and likely associated with the transformation of kaolinite in metakaolinite, is affected in a similar way by soaking time and firing temperature, in line with the concept of equivalent firing temperature. At temperatures from 800 to 1100 °C, the structural modifications involving interconnectivity and average pore size are driven primarily by firing temperature and, secondarily, by soaking time. The 2D 1H NMR-R results are confirmed by more traditional, but destructive, mineralogical, and structural analyses like X-ray powder diffraction, helium pycnometry, mercury intrusion porosimetry, and nitrogen adsorption/desorption method. 相似文献
14.
Giulia Vallarino Annalisa Salis Elena Lucarini Federica Turrini Guendalina Olivero Alessandra Roggeri Gianluca Damonte Raffaella Boggia Lorenzo Di Cesare Mannelli Carla Ghelardini Anna Pittaluga 《Molecules (Basel, Switzerland)》2022,27(3)
A new formulation of a pomegranate-peel extract (PEm) obtained by PUAE (Pulsed Ultrasound-Assisted Extraction) and titrated in both ellagic acid (EA) and punicalagin is proposed, characterized and then analyzed for potential health properties in mice suffering from the experimental autoimmune encephalomyelitis (EAE). PEm effects were compared to those elicited by a formulation containing EA (EAm). Control and EAE mice were chronically administered EAm and Pem dissolved in the drinking water, starting from the day 10 post-immunization (d.p.i.), with a “therapeutic” protocol to deliver daily 50 mg/kg of EA. Treated EAE mice did not limit their daily access to the beverage, nor did they show changes in body weight, but they displayed a significant amelioration of “in vivo” clinical symptoms. “Ex vivo” histochemical analysis showed that spinal-cord demyelination and inflammation in PEm and EAm-treated EAE mice at 23 ± 1 d.p.i. were comparable to those in the untreated EAE animals, while microglia activation (measured as Ionized Calcium Binding Adaptor 1, Iba1 staining) and astrocytosis (quantified as glial fibrillar acid protein, GFAP immunopositivity) significantly recovered, particularly in the gray matter. EAm and PEm displayed comparable efficiencies in controlling the spinal pathological cellular hallmarks in EAE mice, and this would support their delivery as dietary supplementation in patients suffering from multiple sclerosis (MS). 相似文献
15.
Lignans are particularly interesting secondary metabolites belonging to the phenyl-propanoid biosynthetic pathway. From the structural point of view, these molecules could belong to the aryltetralin, arylnaphtalene, or dibenzylbutyrolactone molecular skeleton. Lignans are present in different tissues of plants but are mainly accumulated in seeds. Extracts from plant tissues could be characterized by using the NMR-based approach, which provides a profile of aromatic molecules and detailed structural information for their elucidation. In order to improve the production of these secondary metabolites, elicitors could effectively stimulate lignan production. Several plant species are considered in this review with a particular focus on Linum species, well recognized as the main producer of lignans. 相似文献
16.
Mario Olivieri Gianluca Spiteri Jessica Brandi Daniela Cecconi Marina Fusi Giovanna Zanoni Corrado Rizzi 《Molecules (Basel, Switzerland)》2022,27(4)
Wheat allergens are responsible for symptoms in 60–70% of bakers with work-related allergy, and knowledge, at the molecular level, of this disorder is progressively accumulating. The aim of the present study is to investigate the panel of wheat IgE positivity in allergic Italian bakers, evaluating a possible contribution of novel wheat allergens included in the water/salt soluble fraction. The water/salt-soluble wheat flour proteins from the Italian wheat cultivar Bolero were separated by using 1-DE and 2-DE gel electrophoresis. IgE-binding proteins were detected using the pooled sera of 26 wheat allergic bakers by immunoblotting and directly recognized in Coomassie stained gel. After a preparative electrophoretic step, two enriched fractions were furtherly separated in 2-DE allowing for detection, by Coomassie, of three different proteins in the range of 21–27 kDa that were recognized by the pooled baker’s IgE. Recovered spots were analyzed by nanoHPLC Chip tandem mass spectrometry (MS/MS). The immunodetected spots in 2D were subjected to mass spectrometry (MS) analysis identifying two new allergenic proteins: a glucose/ribitol dehydrogenase and a 16.9 kDa class I heat shock protein 1. Mass spectrometer testing of flour proteins of the wheat cultivars utilized by allergic bakers improves the identification of until now unknown occupational wheat allergens. 相似文献
17.
The physical behavior of a fluid in contact with solid layers is still not fully understood. The present work focuses on the
study and understanding of thermodynamic and structural properties of gold–water nanolayer mixtures using molecular dynamics
simulations. Two different systems are considered, where approximately 1,700 water molecules are confined between gold nanolayers
with separations of 7.4 and 6.2 nm, respectively. Novelties of the present work are in the use of accurate force fields for
modeling the inter- and intra-molecular interactions of the components, and providing comprehensive thermodynamic properties
of the mixtures. The results are validated by examination of the pure fluid and pure solid properties. Results indicate that
the thermodynamics of the system does not behave as an ideal mixture. The structure of the pure fluid is also analyzed and
compared against the structure of the confined fluid in the mixture. Anisotropicity is observed in the fluid structure close
to the surface of the nanolayer. Higher ordering and higher flux are detected in the fluid molecules close to the fluid–solid
interface. Unusual thermodynamic behavior, anisotropicity, liquid layering, and higher interfacial fluid flux could be just
some of the factors leading to the enhanced energy transport observed in mixtures involving at least one nanoscale component,
such as nanofluids. 相似文献
18.
Solar System tests give nowadays constraints on the estimated value of the cosmological constant, which can be accurately
derived from different experiments regarding gravitational redshift, light deflection, gravitational time-delay and geodesic
precession. Assuming that each reasonable theory of gravitation should satisfy Solar System tests, we use these limits on
the estimated value of the cosmological constant to constrain extended theories of Gravity, which are nowadays studied as
possible theories for cosmological models and provide viable solutions to the cosmological constant problem and the explanation
of the present acceleration of the Universe. We obtain that the estimated values, from Solar System tests, for the parameters
appearing in the extended theories of Gravity are orders of magnitude bigger than the values obtained in the framework of
cosmologically relevant theories. 相似文献
19.
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