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31.
LetT B(H) be a bounded linear operator on a complex Hilbert spaceH. Let 0 (T) be an isolated point of (T) and let
be the Riesz idempotent for 0. In this paper, we prove that ifT isp-hyponormal or log-hyponormal, thenE is self-adjoint andE
H=ker(H–0)=ker(H–0
*.This research was supported by Grant-in-Aid Research 1 No. 12640187. 相似文献
32.
Nine new secoiridoid glucosides from Jasminum nudiflorum 总被引:2,自引:0,他引:2
Takenaka Y Tanahashi T Taguchi H Nagakura N Nish T 《Chemical & pharmaceutical bulletin》2002,50(3):384-389
Phytochemical study of the leaves of Jasminum nudiflorum has led to the isolation of nine new secoiridoid glucosides, jasnudiflosides F-L (1-7), nudifloside D (8) and isooleoacteoside (9). The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence. 相似文献
33.
The Furuta inequality with negative powers 总被引:2,自引:0,他引:2
Let be bounded linear operators on a Hilbert space satisfying . Furuta showed the operator inequality
as long as positive real numbers satisfy and . In this paper, we show this inequality is valid if negative real numbers satisfy a certain condition. Also, we investigate the optimality of that condition.
as long as positive real numbers satisfy and . In this paper, we show this inequality is valid if negative real numbers satisfy a certain condition. Also, we investigate the optimality of that condition.
34.
Parallel synthesis and high throughput dissolution testing of biodegradable polyanhydride copolymers
Vogel BM Cabral JT Eidelman N Narasimhan B Mallapragada SK 《Journal of combinatorial chemistry》2005,7(6):921-928
We have demonstrated that polycondensation reactions can be carried out in a combinatorial fashion and that the polymer library can be screened at high throughput using a rapid prototyping technique to fabricate multiwell substrates. A linearly varying compositional library of 100 different biodegradable polyanhydride random copolymers that are promising carriers for controlled drug delivery was designed, fabricated, and characterized by IR microscopy within a few hours. The polyanhydride copolymer library was based on 1,6-bis(p-carboxyphenoxy)hexane (CPH) and sebacic anhydride (SA) and was characterized with infrared microspectroscopy to determine the composition within each well. Since degradation and release rates depend on copolymer composition, we also developed new high-throughput methods to investigate drug release from this library of copolymers by designing specific wells for each task. A subset of this library was chosen, and a substrate was designed and fabricated to enable the synthesis and monitoring of dye dissolution from a range of polyanhydride copolymers in a parallel fashion using a CCD camera. Multisample substrates were fabricated with a novel rapid prototyping method that consists of an organic solvent-resistant array of 10 x 10 microwells of 2-muL volume each. The libraries were deposited with a custom-built liquid dispensing system consisting of a series of computer-controlled volume-dispensing pumps and XYZ motion stages. The parallel dye dissolution study displayed a decreasing rate of release with increasing CPH content. This result agrees with previously published data for dye release from poly(CPH-co-SA) copolymers. The methodology described in this work is amenable to numerous applications in the arenas of high-throughput polymer synthesis and characterization. 相似文献
35.
Advances in scattering-based optical imaging technologies offer a new approach to noninvasive point-of-care detection, diagnosis, and monitoring of cancer. Emerging photonics technologies provide a cost-effective means to image tissue in vivo with high resolution in real time. Advancing the clinical potential of these imaging strategies requires the development of optical contrast agents targeted to specific molecular signatures of disease. We describe the use of a novel class of contrast agents based on nanoshell bioconjugates for molecular imaging in living cells. Nanoshells offer significant advantages over conventional imaging probes including continuous and broad wavelength tunability, far greater scattering and absorption coefficients, increased chemical stability, and improved biocompatibility. We show that nanoshell bioconjugates can be used to effectively target and image human epidermal growth factor receptor 2 (HER2), a clinically relevant biomarker, in live human breast carcinoma cells. 相似文献
36.
Electronically modified PHOX ligands 3a-e were synthesized to probe the mechanism of the enantioselective palladium-catalyzed allylic alkylation and amination reactions. Alkylation with dimethyl sodiomalonate produced only a small variation in the ee (89.3% to 93.4%), but amination with benzylamine gave a much wider variation in the ee (16.4% to 66.6%). Hammett analysis suggests that the substituents interact more significantly with phosphorus and supports a combined electronic and steric basis for enantioselection. [reaction: see text] 相似文献
37.
Let be invertible bounded linear operators on a Hilbert space satisfying , and let be real numbers satisfying Furuta showed that if , then . This inequality is called the grand Furuta inequality, which interpolates the Furuta inequality
and the Ando-Hiai inequality ( ).
and the Ando-Hiai inequality ( ).
In this paper, we show the grand Furuta inequality is best possible in the following sense: that is, if , then there exist invertible matrices with which do not satisfy .
38.
Kô tarô Tanahashi Atsushi Uchiyama 《Proceedings of the American Mathematical Society》2000,128(6):1691-1695
Let be real numbers with and Furuta (1987) proved that if bounded linear operators on a Hilbert space satisfy , then . This inequality is called the Furuta inequality and has many applications. In this paper, we prove that the Furuta inequality holds in a unital hermitian Banach -algebra with continuous involution.
39.
From the quaternary alkaloidal fraction of the dried tubers of Stephania cepharantha, two new isoquinoline alkaloids, stecepharine and tetradehydroreticuline have been isolated along with the known compounds, magnoflorine, menisperine, steponine, cyclanoline, oblongine, cis-N-methylcapaurine and 2'-N-methylisotetrandrine. cis-N-Methylcapaurine (=9-O-methylstecepharine) was isolated as a natural product for the first time. Their structures were determined on the basis of spectroscopic evidence. 相似文献
40.