properties of the discrete time fourier transform

Ngày tải lên: 30/10/2014, 20:11

Ngày tải lên: 31/03/2014, 15:21

Ngày tải lên: 21/06/2014, 16:20

... Trong miền tần số: phương pháp Fourier Transform. - Trong miền thời gian và tần số: STFT( Short Time Fourier Transform) . 2.4.1. Phương pháp Fourier: 2.4.1.1. Biến đổi Fourier: Cho một hàm f(t) ... được một biến đổi Fourier cục bộ, chúng ta có thể định nghĩa một biến đổi Fourier cửa sổ. Tín hiệu đầu vào được nhân với một hàm cửa sổ W (t - τ) và sau đó lấy biến đổi Fourier của nó. Kết ... đổi Fourier của nó được định nghĩa: () () () tfedtetfF titj , ωω ω == ∫ ∞ ∞− − (2.14) Biến đổi Fourier ngược là: () () ∫ ∞ ∞− = ωω π ω deFtf tj 2 1 (2.15) Giả sử rằng biến đổi Fourier...

Ngày tải lên: 01/04/2013, 16:14

Ngày tải lên: 05/09/2013, 14:58

... changes over time impossible. The objectives of the present combined analysis were to evaluate the psychometric properties of the CHIP-CE at baseline and over time and to assess the correlation between ... to use the sub-domains rather than the domains of the CHIP- CE when evaluating ADHD patients. This is supported by the factor analysis based on the sub-domains and the correlation analysis of the ... and the core symptoms. The influ- ence of the QoL of the parents or the parents’ diseases (such as ADHD) could not be assessed because these data were not obtained. Conclusions The strength of...

Ngày tải lên: 12/02/2014, 19:20

... presenting the pulse of Src activity in the plane of the inactive and active fractions, s i and s 1 . If the duration of the stimulus exceeds the critical value, the trajectory in the (s i , ... 2009 The Authors Journal compilation ê 2009 FEBS parameters and, for clarity of exposition, we present the analysis of the Src cycle in terms of Eqns (6–8). Intrinsic regulatory properties of the ... steady states of the Src cycle. When there are three intersections, the steady state O 1 at the lower branch of the Z-shaped curve (i.e. low Src activity) and the state O 3 at the upper branch...

Ngày tải lên: 18/02/2014, 11:20

... cleft, the putative catalytic zinc being at the bottom of the cleft and a lobe containing the structural zinc at the mouth of the cleft and thus exposed to the solvent [8]. Grad- ual depletion of the ... However, the addition of ZnCl 2 to the incubation buffers showed a marked effect on the stability of the enzyme at both high temperature and acidity. This effect was the same across the range of ZnCl 2 concen- trations ... Novagen. Expression of Pt-gdh under the control of araB promoter was induced for 4 h at 30 °C by the addition of 0.2% ara- binose when the A 600 of the growing culture reached 0.5. The cells from...

Ngày tải lên: 19/02/2014, 16:20

... to the different environ- ment of the heme centers. The difference signals observed at 442 nm and 603 nm can be assigned to the contributions of the hemes a and a 3 , with the position of the ... modes on the basis of the data presented here, in spite of the fact that bands in the difference spectra are observed in the region where the modes were attributed. The vibrational modes of bound ... particular problem of the assignment in the difference spectra is the superposition of signals from different constituents of the oxidase, which can lead to the possibility of multi component...

Ngày tải lên: 21/02/2014, 15:20

... solution by the rest of the protein. There is no correlation between the complex stability and the rate of its formation. The Ni(II) for Cu(II) exchange rates f or peptides are o f the order of 10 )6 s )1 in ... albumins. On the other hand, the direct thermodynamic and kinetic characterization of Ni(II) binding at site I in HSA and BSA was obtained. These data can be very useful in further studies of the toxicolo- gically ... values of *K, the equilibrium constant of the actual complex formation reaction: M ỵ H n L ẳ MH j L ỵnỵjịH ỵ This constant represents the overall ability of ligand L to form a given complex. The other...

Ngày tải lên: 22/02/2014, 04:20

... characterize the time course of change in ventricular mechanical properties by plotting the time course of change in the slope of the instantaneous PVR. Above, we referred to the slope of the ESPVR ... interaction between the ongoing contraction process of the cardiac muscles and the properties of the arterial system and is beyond the scope of this lecture. As the contraction process of the cardiac ... contraction there is a period of time during which the mechanical properties of the heart are characterized by the EDPVR; knowledge of the EDPVR allows one to specify, for the end of diastole,...

Ngày tải lên: 22/02/2014, 09:20

... reverse-phase HPLC on a C 8 column, and the retention time of the obtained prosthetic group was compared with those of flavin derivatives. The retention time of the prosthetic group bound to recom- binant ... of the structure of NADP + -bound FeR revealed that the nicotinamide moiety of NADP + faces the re-side of the isoalloxazine ring, and that the 2Â-P-AMP moiety is held in the groove between the ... direction along the b10 of the other mono- mer, forming an anti-parallel intermolecular b sheet (Fig. 2A). The subsequent residues of the loop (Ala7– Pro13) turn into the interior of the dimer interface, and...

Ngày tải lên: 07/03/2014, 02:20

... alanines are likely. The manner in which the number of alanines determines the atomic structure of the fibril and the b-strand arrangements remains to be determined. Yet, knowledge of the structure and ... using the nanoscope analysis software. Chemical stability of fibrils The chemical stability of fibrils was tested after the fibrilla- tion process was completed (no further rise of ANS sig- nals). The ... consisting primar- ily of PABPN1. Poly l-alanine-dependent fibril formation was studied using the recombinant N-terminal domain of PABPN1. In the case of the protein fragment with the expanded poly...

Ngày tải lên: 07/03/2014, 11:20

... identified by the mass increase of 42 mass units. The relative level of acetylation of a peptide was estimated on the basis of the intensity ratio of the native and acetylated species. From the data ... a-helix in the whole protein, and the 1–70 region is poorly structured. SDS increases the a-helix content of proteins revealing the helical potential. The a-helix content of the monomeric form of SV-IV ... Lys80, showed partial acetylation at one of the three residues, because the signal of the triacetylated species was less intense than that of the diacetylated species. The MS/MS Fig. 2. Secondary-structure...

Ngày tải lên: 07/03/2014, 14:20

... the ferrous state of the mutant may contribute to an increase in the disorder and hence entropy of the reduced state of the mutant compared to that of the wild-type protein. In contrast to the ... disposition of the proximal His and Asp residues, affecting the imidazo- late character of the His, but also by the formation of a LS species. The latter indicating the probable bind- ing of His42 to the ... impact on the properties of His170. The strength of the hydro- gen bond between the proximal His and Asp residues, and thus the imidazolate character of the His is expec- ted to modulate not only the...

Ngày tải lên: 07/03/2014, 21:20

... [1,4]. The protein is known to exist as a dimer and the NHE1 isoform specifically dimerizes to itself and not to other isoforms of the Na + /H + exchanger [5]. Although the NHE1 isoform of the Na + /H + exchanger is ... concentrations of the fractions, together with the relative amount of Na + /H + exchanger present in the supernatant and the pellet [19], it was found that over 80% of the Na + /H + exchanger remained in the ... that could either alter the distribution of the Na + /H + exchanger or the constituency of the lipid rafts, we used an established detergent-free lipid raft isolation procedure for some of our studies...

Ngày tải lên: 08/03/2014, 16:20

... the site of interaction with AKAP proteins [5,6]. The symmetry axis of the dimer is along the y-axis shown in the Figure. Figure 4B shows the van der Waals model of the top face of the best structure ... A further rotation of the orientation of RIIa D/D of Fig. 4B by 180° about the x-axis shows the bottom face of RIIa D/D (Fig. 4C). There is some hydrophobic character in the bottom face of RIIa ... bar at the C-terminus of each helix corresponds to the variable helical range within the ensemble of the 24 structures. There is no variation at amino terminus of each helix. The sequence of ionizable...

Ngày tải lên: 08/03/2014, 22:20

... con- served in the primary structure of the GTPase domain of hGBP5, so the formation of GMP must be impaired in an as yet unknown manner. Sequence alignments of the large GTP-binding domains of hGBP1, ... for the lack of GMP formation (see Fig. S2). The similar hydrolytic activities of the a ⁄ b and C-terminally truncated forms of hGBP5 are in contrast to that of the analogous deletion mutant of hGBP1 ... account). The size of the protein complex is only slightly increased when nucleotide-free or in the presence of GTP. As with hGBP5ta, the complex is increased to the size of a tetramer after binding of GppNHp,...

Ngày tải lên: 15/03/2014, 10:20

... of the PDI [42], and t hat this site is far away from the redox active sites in the sequ ence. Furthermore, the measurements of the rates of PDI-catalysed refolding of scrambled RNase A, in the ... (225 m M )9:1 (25 m M ). At the end of the incubation, 40 lL of the mixture was added to each of the five solutions; these were then left to react on ice for 5 min. The reaction mixtures w ere analysed ... of the active site in the N-unit. As regards the oxidative activity, the two units also display differences in their functional properties, with the site at the C-termus always predominant, the...

Ngày tải lên: 16/03/2014, 16:20