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81.
Rafał I. Rawski Przemysław T. Sanecki Małgorzata Dżugan Klaudia Kijowska 《Chemical Papers》2018,72(5):1213-1221
It has been experimentally proven that germinated plant seeds, such as leek, red clover, broccoli, and others contain proteases, which are able to digest animal protein such as gelatin, bovine albumin, casein, and egg albumin. Preliminary tests were carried out with the use of a semi-qualitative gelatin test, which is often applied to prove the presence of fruit enzymes. Quantitative examinations were carried out with the use of a ninhydrin reaction for amino acid determination as well as the Bradford and Smith methods for protein determination. Respective calibration curves were obtained for glycine (amino acid analysis) as well as for egg albumin, bovine albumin, and gelatin (protein analysis), with a full statistical evaluation including Mandel and Lack-of-Fit tests to check for linearity. It has been proven that the selected germinated seeds containing proteases can be applied as an effective aid for animal protein digestion. 相似文献
82.
Developments in planar electrochromatography in open (PEC) and closed (PPEC) systems are reviewed. The discussion focuses
on progress in chamber construction for planar electrochromatography, separating system performance, equilibration of the
PPEC process, separation time and selectivity, and the general advantages, disadvantages and prospects of this separation
mode.
Presented at the 11th International Conference on Chemistry and the Environment, 9–12 September 2007, Torum, Poland. 相似文献
83.
Gralka E Valensin D Porciatti E Gajda C Gaggelli E Valensin G Kamysz W Nadolny R Guerrini R Bacco D Remelli M Kozlowski H 《Dalton transactions (Cambridge, England : 2003)》2008,(38):5207-5219
The prion protein (PrP) is a Cu(2+)-binding cell-surface glycoprotein. Using PrP peptide fragments, by means of potentiometric, spectroscopic and thermodynamic techniques, we have shown that Cu(2+) ions bind to the region comprising His-96, His-111 and the octarepeat domain within residues 60-91. Cu(2+) may bind in different modes, which strongly depend both on His position within the peptide sequence and on the adjacent residues. We have used a series of protected oligopeptides having His at the C- or the N-terminus, inducing different binding modes to amide nitrogens around the His residue, either towards the N- or C-terminus. His imidazole acts as an anchoring site for Cu(2+) and then binding to ionized amide nitrogens follows. When it is directed towards the C-terminus the formation of a less stable seven-membered chelate ring with a {N(im), N(-)} binding mode occurs. When coordination goes towards the N-terminus the thermodynamically more stable six-membered chelate ring is formed. NMR data suggest that both the coordination modes are possible for the model peptides; however, the thermodynamic measurements show that they only slightly differ in energy and the influence of the adjacent amino acid residues can address the coordination toward the C- or the N-terminus. 相似文献
84.
Anna Żywicka Dorota Peitler Rafał Rakoczy Adam Feliks Junka Karol Fijałkowski 《Applied biochemistry and biotechnology》2016,180(4):805-816
The present study aimed to explore and describe the properties of bacterial cellulose (BC) membranes obtained from three different strains of Gluconacetobacter xylinus for 72, 120, and 168 h, used as a carrier support for the immobilization of Saccharomyces cerevisiae. The experiments also included the analysis of glucose consumption and alcohol production during the fermentation process displayed by yeasts immobilized on the BC surface. The results of the present study demonstrate that the number of immobilized yeast cells is dependent on the type of cellulose-synthesizing strain, cellulose form, and duration of its synthesis. The BC in the form of wet membranes obtained after 3 days of synthesis displayed the most favorable properties as a carrier for yeast immobilization. The immobilization of yeast cells on BC, regardless of its form, increased the amount of the produced alcohol as compared to free cells. The yeast cells immobilized in BC were able to multiply on its surface during the fermentation process. 相似文献
85.
The paper presents the results of investigation studies involving the impact of atmospheric factors on sound-absorbing parameters of roadside acoustic screen panels. The research studies comprised the aging test consisting of 1000 cycles in simulated conditions, sound absorption measurements and surface morphology tests, using the SEM scanning method. The simulation of aging consisted of 100 or 150 cycles at a time. Then, the panels were investigated in the reverberation chamber to define their sound-absorbing properties. The process was repeated until 1000 cycles were completed. Basing on the carried out tests, a statistical linear model was worked out which was used to estimate the value of a single number sound absorption coefficient after successive aging cycles. The optimality of the model was demonstrated by means of a statistical test confirming normal distribution of random residuals. For the research studies, we employed an innovative structural design of panels for which aging characteristics were obtained. Basing on the obtained results and on the statistical analysis, the prospects to maintain acoustic properties of the panels during their service life was estimated. 相似文献
86.
Katarzyna Brodowska Anna Sykuła Eugenio Garribba Elżbieta Łodyga-Chruścińska Michał Sójka 《Transition Metal Chemistry》2016,41(2):179-189
A Schiff base derived from naringenin (NTSC) and its complex with Cu(II) ([Cu(H3L)(OAc)]·H2O, Cu(II)–NTSC) have been synthesized and characterized by physicochemical and spectroscopic methods. EPR studies confirmed that nitrogen, oxygen, and sulfur are the donor atoms bound to Cu(II) in the complex. The geometry of the complex has been modelled using DFT methods. Furthermore, naringenin and NTSC were used for the formation of Cu(II) complexes in solution, for comparison of biological activities. Antioxidant studies confirmed better radical scavenging activity of both NTSC and its Cu(II) complex compared to naringenin. The interaction of these compounds with calf thymus DNA was monitored by UV–Vis spectroscopy. 相似文献
87.
Rafał Pierzchała 《Journal d'Analyse Mathématique》2016,129(1):285-307
The paper contains a full geometric characterization of compact semialgebraic sets in C satisfying the ?ojasiewicz-Siciak condition. The ?ojasiewicz-Siciak condition is a certain estimate for the Siciak extremal function. In a previous paper, we gave a sufficient criterion for a compact, connected, and semialgebraic set in C to satisfy this condition. In the present paper, we remove completely the connectedness assumption and prove that the aforementioned sufficient condition is also necessary. Moreover, we obtain some new results concerning the ?ojasiewicz-Siciak condition in CN. For example, we prove that if K1,...,Kp are compact, nonpluripolar, and pairwise disjoint subsets of CN, each satisfying the ?ojasiewicz-Siciak condition, and K:= K1?· · ·?Kp is polynomially convex, then K satisfies this condition as well. 相似文献
88.
Paweł Głowacki 《Arkiv f?r Matematik》2007,45(1):31-48
The purpose of this note is to give an extension of the symbolic calculus of Melin for convolution operators on nilpotent
Lie groups with dilations. Whereas the calculus of Melin is restricted to stratified nilpotent groups, the extension offered
here is valid for general homogeneous groups. Another improvement concerns the L
2-boundedness theorem, where our assumptions on the symbol are relaxed. The zero-class conditions that we require are of the
type
where ρ
j
are “partial homogeneous norms” depending on the variables ξ
k
for k>j in the natural grading of the Lie algebra (and its dual) determined by dilations. Finally, the class of admissible weights
for our calculus is substantially broader. Let us also emphasize the relative simplicity of our argument compared to that
of Melin. 相似文献
89.
90.
Paweł Keller 《Numerical Algorithms》2007,46(3):219-251
We propose a general method for computing indefinite integrals of the form
where g is a smooth function, and k is a function that contains a singular factor or is rapidly oscillatory. The only assumption on k is that it satisfies a linear differential equation with polynomial coefficients. The approximate value of the integral is
given in terms of Chebyshev coefficients of functions that form a solution of a certain system of differential equations.
As an illustration, we present effective algorithms for computing indefinite integrals of the functions g(t)|t–d|
α
e
i
ω
t
, g(t)log|t–d| e
i
ω
t
, g(t) t
α
J
ν
(ct).
相似文献