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71.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献
72.
Classical molecular dynamics simulations have been performed for crystalline germanium with the aim to estimate the thermal
effects within the first three coordination shells and their influence on the single-scattering and multiple-scattering contributions
to the Ge K-edge extended x-ray absorption fine structure (EXAFS). 相似文献
73.
Alexei Borodin Mihail Poplavskyi Christopher D. Sinclair Roger Tribe Oleg Zaboronski 《Communications in Mathematical Physics》2016,346(3):1051-1055
We correct an error in Theorem 12 of the original article concerning the edge scaling limit of the law of real eigenvalues for the real Ginibre ensemble. 相似文献
74.
75.
Let be an oriented Jordan smooth curve and a diffeomorphism of onto itself which has an arbitrary nonempty set of periodic points. We prove criteria for one-sided invertibility of the binomial functional operator
wherea andb are continuous functions,I is the identity operator,W is the shift operator,Wf=fo, on a reflexive rearrangement-invariant spaceX() with Boyd indices
X
,
X
and Zippin indicesp
x,q
x satisfying inequalities
Partially supported by F.C.T. (Portugal) grant PRAXIS XXI/BPD/22006/99.Partially supported by CONCACYT (México) grant, Cátedra Patrimonial, No. 990017-EX., nivel II. 相似文献
76.
We consider a one-dimensional charge density wave insulator formed by umklapp processes in a quarter-filled band. The spectrum of the model consists of gapless, uncharged excitations carrying spin +/- 1/2 (spinons) and gapped, spinless excitations carrying charge -/+ signe/2 (solitons and antisolitons). We calculate the low-energy behavior of the single-electron Green's function at zero temperature. The spectral function exhibits a featureless scattering continuum of two solitons and many spinons. The theory predicts that the gap observed by angle resolved photoemission is twice the activation gap in the dc conductivity. We comment on possible applications to PrBa(2)Cu(3)O(7) and to the Bechgaard salts. 相似文献
77.
Correlation integral as a tool for distinguishing between dynamics and statistics in time series data 总被引:2,自引:0,他引:2
We propose a new test for time series data for proper choice of processing technique: dynamical or statistical. It is based upon the normalized slope of the correlation integral (, m) = m−1d(ln C()) /d ln , where m is the embedding dimension. It is shown that when does not tend to 0 on the resolved range of scales as m grows, then there will be serious limitations for dynamical methods even if the data are dynamical by nature. In the latter case it means that the length of time series does not allow to resolve small scales, and on large scales the delay reconstruction for any m mixes true and false neighbours of points and therefore restricts the application of dynamical techniques, such as estimating Lyapunov exponents or predicting time series. 相似文献
78.
Femtosecond laser-driven approximately 1 GPa shock waves are used to compress monolayers of hydrocarbon chains. Vibrational sum-frequency generation spectroscopy probes the orientation of the terminal methyl groups. With an odd number (15) of carbon atoms, shock compression is an elastic process that causes the methyl groups to tilt. With an even number (18) of carbon atoms, shock compression is viscoelastic, creating single and double gauche defects. When the shock unloads, single gauche defects remain while double defects relax in 30 ps to single-defect states with more upright methyl groups. 相似文献
79.
This study revisits the classical x-ray diffraction patterns from hydrated, noncrystalline fibers originally used to establish the helical structure of DNA. We argue that changes in these diffraction patterns with DNA packing density reveal strong azimuthally dependent interactions between adjacent molecules up to approximately 40 A interaxial or approximately 20 A surface-to-surface separations. These interactions appear to force significant torsional "straightening" of DNA and strong azimuthal alignment of nearest neighbor molecules. The results are in good agreement with the predictions of recent theoretical models relating DNA-DNA interactions to the helical symmetry of their surface charge patterns. 相似文献
80.
Morton JJ Tyryshkin AM Ardavan A Porfyrakis K Lyon SA Briggs GA 《Physical review letters》2005,95(20):200501
Systematic errors in spin rotation operations using simple rf pulses place severe limitations on the usefulness of the pulsed magnetic resonance methods in quantum computing applications. In particular, the fidelity of quantum logic operations performed on electron spin qubits falls well below the threshold for the application of quantum algorithms. Using three independent techniques, we demonstrate the use of composite pulses to improve this fidelity by several orders of magnitude. The observed high-fidelity operations are limited by pulse phase errors, but nevertheless fall within the limits required for the application of quantum error correction. 相似文献