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81.
The relation between the lifetimes of the triplet states of various porphyrins and their photosensitizing effects on the photodynamic therapy (PDT) of tumor has been examined. Diethylene-triamine pentaacetic acid ester of 4-[1-(2-hydroxy-ethyloxy)ethyl]-2-vinyl deuteroporphyrin-IX gallium (III) complex (Ga-DP), zinc (II) complex (Zn-DP), and manganese (III) complex (Mn-DP) and Photofrin II (PII) are used as the photosensitizer. The triplet lifetimes have been measured for the samples adsorbed on filter paper (FP) and found to be 57 ms (Ga-DP), 26 ms (Zn-DP), less than or equal to 10 microseconds (Mn-DP) and 9 ms (PII). The phosphorescence of Ga-DP in tumor-bearing golden hamsters are measured both in tumor tissue and in liver. They show bi-exponential decay with the lifetimes of about 5 and 20 ms. From the values, the generation rate, kct[3O2], of singlet molecular oxygen in living animal tissue may be estimated to be an order of 10(2) s-1. The PDT effects have been quantitatively investigated for in vitro experiments; upon irradiation the growth inhibitions of mouse p388 leukemia cells are obtained as a function of concentration of Ga-DP, Zn-DP, Mn-DP and PII. The experimental results indicate that the PDT effects depend essentially on the triplet lifetimes of the photosensitizers. 相似文献
82.
Consider a general n-way crossed classification in ANOVA with unequal cell frequencies. We prove the orthogonality of interaction spaces (suitably adjusted for lower order interaction spaces) holds if and only if the cell frequencies are proportional. Implications of proportional cell frequencies to the adjustment of all other effects are also studied. 相似文献
83.
We consider the asymptotic joint distribution of the eigenvalues and eigenvectors of Wishart matrix when the population eigenvalues become infinitely dispersed. We show that the normalized sample eigenvalues and the relevant elements of the sample eigenvectors are asymptotically all mutually independently distributed. The limiting distributions of the normalized sample eigenvalues are chi-squared distributions with varying degrees of freedom and the distribution of the relevant elements of the eigenvectors is the standard normal distribution. As an application of this result, we investigate tail minimaxity in the estimation of the population covariance matrix of Wishart distribution with respect to Stein's loss function and the quadratic loss function. Under mild regularity conditions, we show that the behavior of a broad class of tail minimax estimators is identical when the sample eigenvalues become infinitely dispersed. 相似文献
84.
We investigated the hole trap level of nitrogen-doped ZnSe grown by a metalorganic vapor phase epitaxy method. The deep level transient spectroscopy (DLTS) signal and the C-V profile were measured to obtain the trap level, the capture cross section and the trap concentration. A deep hole trap level of about 1 eV from a valence band (labeled TLIS) was extracted from the tail of the DLTS peak. The distributions of the capture cross section and the trap level of the samples for different growth conditions were drawn in a figure to investigate the validity of the resolution of the DLTS signal. The origin of TLIS is thought to be in relation to the ionized acceptor or the charged acceptor-like localized defects. 相似文献
85.
Kentaro Tanaka Akimichi Takemura 《Annals of the Institute of Statistical Mathematics》2005,57(1):1-19
We consider maximum likelihood estimation of finite mixture of uniform distributions. We prove that maximum likelihood estimator
is strongly consistent, if the scale parameters of the component uniform distributions are restricted from below by exp(−n
d
), 0<d<1, wheren is the sample size. 相似文献
86.
Masayuki Kumon Akimichi Takemura 《Annals of the Institute of Statistical Mathematics》2008,60(4):801-812
In the framework of the game-theoretic probability of Shafer and Vovk it is of basic importance to construct an explicit strategy weakly forcing the strong law of large numbers in the bounded forecasting game. We present a simple finite-memory strategy based on the past average of Reality’s moves, which weakly forces the strong law of large numbers with the convergence rate of ${O(\sqrt{\log n/n})}In the framework of the game-theoretic probability of Shafer and Vovk it is of basic importance to construct an explicit strategy
weakly forcing the strong law of large numbers in the bounded forecasting game. We present a simple finite-memory strategy
based on the past average of Reality’s moves, which weakly forces the strong law of large numbers with the convergence rate
of . Our proof is very simple compared to a corresponding measure-theoretic result of Azuma (T?hoku Mathematical Journal, 19, 357–367, 1967) on bounded martingale differences and this illustrates effectiveness of game-theoretic approach. We also
discuss one-sided protocols and extension of results to linear protocols in general dimension. 相似文献
87.
Daiguji H Makuta T Kinoshita H Oyabu T Takemura F 《The journal of physical chemistry. B》2007,111(30):8879-8884
A fabrication method for hollow melamine-formaldehyde microcapsules from microbubble templates is presented. This method is based on the direct encapsulation of microbubbles, and thus does not require a liquid- or solid-core decomposition process. This study determined the conditions for controlling the surface morphology, shell thickness, and diameter distribution of hollow microcapsules. Results showed that the surface morphology of these hollow microcapsules depended on the reaction time, glycine concentration (pH of aqueous continuous phase) and pre-polymer concentration. The capsule shell thickness could be controlled by adjusting the concentration of aniline that had adsorbed on the microbubble surface and reacted with pre-polymer. The capsule diameter depended on the dissolution rate of gases, and the diameter of the hollow microcapsules fabricated from air microbubble templates ranged from 5 to 200 microm. 相似文献
88.
H. Ueno D. Kameda D. Nagae M. Takemura K. Asahi K. Shimada K. Takase T. Sugimoto T. Nagatomo M. Uchida T. Arai T. Inoue A. Yoshimi T. Kawamura K. Narita 《The European physical journal. Special topics》2007,150(1):185-186
Ground-state magnetic-dipole moments (μ) of 30-32Al and
electric quadrupole moments (Q) of 31,32Al have been measured
with the β-NMR method using spin-polarized radioactive-isotope
beams produced in projectile-fragmentation reactions. Beams of
30-32Al were obtained by using RIKEN projectile-fragment
separator RIPS after the fragmentation of 40Ar projectiles at an
energy of E = 95A MeV on a 93Nb target. The obtained
μexp[30-32Al] and
values agree well with shell-model calculations within the sd
shell using the USD interaction. Also, Qexp[31Al]
was found to be small. Thus, we can conclude that these aluminum
isotopes are located outside the island of inversion. 相似文献
89.
Kanako Nakamae Dr. Yukie Takemura Dr. Bunsho Kure Prof. Takayuki Nakajima Prof. Yasutaka Kitagawa Prof. Tomoaki Tanase 《Angewandte Chemie (International ed. in English)》2015,54(3):1016-1021
A linear tetraphosphine, meso‐bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmppm) was used to synthesize linear octapalladium‐extended metal atom chains as discrete molecules of [Pd8(μ‐dpmppm)4](BF4)4 ( 1 ) and [Pd8(μ‐dpmppm)4L2](BF4)4 (L=2,6‐xylyl isocyanide (XylNC; 2 ), acetonitrile ( 3 ), and N,N‐dimethylformamide (dmf; 4 )), which are stable in the solution states and show interesting temperature‐dependent photochemical properties in the near IR region. Variable temperature NMR studies demonstrated that at higher temperature T≈140 °C the Pd8 chains were dissociated into Pd4 fragments, which were thermodynamically self‐aligned to restore the Pd8 chains at lower temperature T<60 °C. The coldspray ionization mass spectra suggested a possibility for further aggregation of the linear tetrapalladium units. 相似文献
90.
New podand-type fluoroionophores having two pyrene moieties: 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfide (3), 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfoxide (4), and 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfone (5), have been synthesized by connecting two 1-pyrenecarbonylmethyl groups with the two hydroxy groups of 2,2′-dihydroxydiphenyl sulfide, sulfoxide, and sulfone, respectively. Their complexation behavior toward alkali metal ions was examined by fluorescence spectroscopy. Among these fluoroionophores, compound 4, having a sulfinyl group, showed high selectivity toward Li?. 相似文献