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141.
Jan Oszmiaski Sabina Lachowicz Paulina Nowicka Pawe Rubiski Tomasz Cebulak 《Molecules (Basel, Switzerland)》2021,26(9)
The present study aimed to evaluate the effect of Jerusalem artichoke processing methods and drying methods (freeze drying, sublimation drying, vacuum drying) on the basic physicochemical parameters, profiles and contents of sugars and polyphenolic compounds, and health-promoting properties (antioxidant activity, inhibition of the activities of α-amylase, α-glucosidase, and pancreatic lipase) of the produced purée. A total of 25 polyphenolic compounds belonging to hydroxycinnamic phenolic acids (LC-PDA-MS-QTof) were detected in Jerusalem artichoke purée. Their average content in the raw material was at 820 mg/100 g dm (UPLC-PDA-FL) and was 2.7 times higher than in the cooked material. The chemical composition and the health-promoting value of the purées were affected by the drying method, with the most beneficial values of the evaluated parameters obtained upon freeze drying. Vacuum drying could offer an alternative to freeze drying, as both methods ensured relatively comparable values of the assessed parameters. 相似文献
142.
Sabina Cauci Serena Xodo Cinzia Buligan Chiara Colaninno Mattia Barbina Giuseppe Barbina Maria Pia Francescato 《Molecules (Basel, Switzerland)》2021,26(4)
Information concerning the mechanisms underlying oxidative stress and low-grade inflammation in young healthy women predisposing eventually to future diseases is scarce. We investigated the relationship of oxidative stress and high-sensitivity C-reactive protein (hsCRP) in fertile-age women by oral combined contraceptive (OC) use. Caucasian Italian healthy non-obese women (n = 290; 100 OC-users; 190 non-OC-users; mean age 23.2 ± 4.7 years) were analyzed. Blood hydroperoxides, as oxidative stress biomarkers, were assessed by Free Oxygen Radical Test (FORT). Serum hsCRP was determined by an ultra-sensitive method (hsCRP). Markedly elevated oxidative stress (≥400 FORT Units) was found in 77.0% of OC-users and 1.6% of non-OC-users, odds ratio (OR) = 209, 95% CI = 60.9–715.4, p < 0.001. Elevated hsCRP levels ≥ 2.0 mg/L, considered risky for cardiovascular diseases (CVDs), were found in 41.0% of OC-users and 9.5% of non-OC-users, OR = 6.6, 95%CI 3.5–12.4, p < 0.001. Hydroperoxides were strongly positively correlated to hsCRP in all women (rs = 0.622, p < 0.001), in OC-users (rs = 0.442, p < 0.001), and in non-OC-users (rs = 0.426, p < 0.001). Women with hydroperoxides ≥ 400 FORT Units were eight times as likely to have hsCRP ≥ 2 mg/L. In non-OC-users only, hydroperoxides values were positively correlated with weight and body mass index, but negatively correlated with red meat, fish and chocolate consumption. Our research is the first finding a strong positive correlation of serum hydroperoxides with hsCRP, a marker of low-grade chronic inflammation, in young healthy women. Further research is needed to elucidate the potential role of these two biomarkers in OC-use associated side-effects, like thromboembolism and other CVDs. 相似文献
143.
144.
Anton J. Stasyuk Dr. Sabina Smoleń Dr. Eliza Glodkowska‐Mrowka Dr. Wojciech Brutkowski Prof. Michał K. Cyrański Prof. Nikolai Tkachenko Prof. Dr. Daniel T. Gryko 《化学:亚洲杂志》2015,10(3):553-558
The repertoire of synthetic methods leading to aza‐analogues of polycyclic aromatic heterocycles has been enlarged by the discovery of the rearrangement of 10‐substituted benzo[h]quinolines into compounds bearing an azonia‐pyrene moiety. Acid‐mediated intramolecular cyclization of derivatives bearing ‐CH2CN and ‐CH2CO2Et groups led to compounds bearing a 5‐substituted benzo[de]pyrido[3,2,1‐ij]quinolinium core. Advanced photophysical studies including time‐correlated single photon counting (TCSPC) and transient absorption spectroscopy of 5‐aminobenzo[de]pyrido[3,2,1‐ij]quinolin‐4‐ium salt and 5H‐benzo[de]pyrido[3,2,1‐ij]quinolin‐5‐one showed their promising optical properties such as high fluorescence quantum yields (37–59 %), which was almost independent of the solvent, and high tenability of the absorption band position upon changing the solvent. The benzo[de]pyrido[3,2,1‐ij]quinolinium salt selectively stains nucleic acids (in the nucleus and mitochondria) in eukaryotic cells. 相似文献
145.
J. García‐Melin J. Sabina de Lis 《Mathematical Methods in the Applied Sciences》2000,23(16):1467-1489
In this paper we are giving a complete account, as $\lambda\rightarrow\infty$\nopagenumbers\end , of all possible solutions u to the problem $u_{xx}+\lambda f(u)=0,\;u(0)=u(1)=0$\nopagenumbers\end which satisfy $0\leq u(x)\leq M\;\hbox{in}\; 0 < x<1$\nopagenumbers\end for some fixed $M>0$\nopagenumbers\end . A complete classification of them together with a detailed analysis of their limit profile, including exact location of ‘inner layers’, is given, their stability character is also determined. The analysis is completed by studying the cases where solutions u degenerate at zeros of f and considering also the p‐Laplacian version of the problem where the diffusion term is replaced by the operator $(|u_{x}|^{p‐2}u_x)_x,\;p>1$\nopagenumbers\end . Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
146.
A two-stage Tikhonov regularisation procedure has been used to obtain rheological properties for a high internal phase emulsion
from gap-dependent steady-state parallel plate shear data. This method is beneficial in that it can convert the steady shear
data into rheological property functions. The built-in regularisation parameters of the method are able to keep noise amplification
under control. The two-stage method is able to obtain not only the shear stress–shear rate function but also the apparent
slip velocity as a function of wall shear stress. The method is such that it obtains the rheological functions over the maximum
range of shear rate covered by the data. The results obtained using the new method are compared to those obtained using the
vane geometry with good agreement being observed. 相似文献
147.
Pawe Wagner Sabina Niemczyk‐Baltro Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):o83-o84
In the title compound, C8H8N2OS, strong intramolecular N—H⋯O hydrogen bonds [N⋯O = 2.669 (3) and 2.618 (3) Å] form almost planar six‐membered rings and enforce the conformation of the molecule. Two kinds of intermolecular N—H⋯S hydrogen bonds [N⋯S = 3.309 (3)–3.456 (2) Å] between two symmetry‐independent molecules form consecutive dimers that expand in ribbons along the [100] direction. 相似文献
148.
O. C. Valdiviezo-Mijangos V. M. Levin F. J. Sabina 《Archive of Applied Mechanics (Ingenieur Archiv)》2009,79(1):51-67
This paper deals with the problem of multiple scattering by a random distribution of spherical solid particles in a solid.
The material properties of both media are taken as thermoelastic. The radii of the inclusions may be different. The self-consistent
method in its variant of the effective medium is used to find the dispersion and attenuation of quasi-elastic, quasi-thermal
and shear waves. The single scattering problem required by this technique is solved approximately by means of the Galerkin
method applied to an integral equation using the Green function. Numerical results display a characteristic resonance phenomena
which appears in the interval where the results are approximately valid, that is, for very long waves down to wavelengths
about twice the largest diameter of the spheres. Examples are shown, for composites with two sets of inclusions, which have
either a very similar or dissimilar size. Comparisons are made with the elastic counterpart. Among the material properties,
the mass density ratio, inclusion to matrix, seems to play an important and simple role. Frequency intervals are distinguished
and shown to depend on that ratio, where the attenuation and dispersion of quasi-elastic and P-waves are either very close
to each other or not at all. The same applies to shear waves in either composite. The mass density ratio also displays a simple
monotonic decreasing behaviour as a function of the frequency at the first attenuation maximum and velocity minimum. These
results may be of interest for the nondestructive testing characterization of particulate composites. 相似文献
149.
In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of Bloch-Floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces. 相似文献
150.
Alice?C.?Niemeyer Sabina?B.?PannekEmail author Cheryl?E.?Praeger 《Archiv der Mathematik》2012,98(2):105-114
We call an element of a finite general linear group GL(d, q) fat if it leaves invariant and acts irreducibly on a subspace of dimension greater than d/2. Fatness of an element can be decided efficiently in practice by testing whether its characteristic polynomial has an irreducible
factor of degree greater than d/2. We show that for groups G with SL(d, q) ≤ G ≤ GL(d, q) most pairs of fat elements from G generate irreducible subgroups, namely we prove that the proportion of pairs of fat elements generating a reducible subgroup,
in the set of all pairs in G × G, is less than q
−d+1. We also prove that the conditional probability to obtain a pair (g
1, g
2) in G × G which generates a reducible subgroup, given that g
1, g
2 are fat elements, is less than 2q
−d+1. Further, we show that any reducible subgroup generated by a pair of fat elements acts irreducibly on a subspace of dimension
greater than d/2, and in the induced action the generating pair corresponds to a pair of fat elements. 相似文献