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131.
On the setting of the half-space we introduce the Schatten-Herz classes of Toeplitz operators and obtain characterizations
for positive Toeplitz operators to belong to those classes. We also prove results concerning the boundedness and compactness
of Toeplitz operators with Herz symbols. Such a study has been recently done on the ball. At a critical step of the proofs
we employ a much simplified argument to extend the range of parameters for Herz spaces on which the Berezin transform is bounded.
Our results show not only that most of results on the ball continue to hold, but also that there is some pathology caused
by the unboundedness of the domain.
The first author was in part supported by a Korea University Grant(2007), the second author was in part supported by Hanshin
University Research Grant, and both authors were in part supported by KOSEF(R01-2003-000-10243-0). 相似文献
132.
Mariem Saada Hanen Wasli Ins Jallali Rim Kboubi Karl Girard-Lalancette Vakhtang Mshvildadze Riadh Ksouri Jean Legault Susana M. Cardoso 《Molecules (Basel, Switzerland)》2021,26(19)
The fractionation of the methanolic extract (MeOH-E) of Retama raetam (Forssk.) Webb & Berthel and further analysis by thin layer chromatography resulted in four fractions (F1, F2, F3 and F4) that, in parallel with the MeOH-E, were screened for antioxidant, cytotoxic, antidiabetic and antibacterial properties. In addition, chemical characterization of their bioactive molecules was performed using LC-DAD-ESI/MSn. The results indicated that F3 was the most promising regarding antioxidant and cytotoxicity abilities, possibly due to its richness in flavonoids class, particularly isoflavones. In turn, F1 was characterized by the presence of the most polar compounds from MeOH-E (organic acids and piscidic acid) and showed promising abilities to inhibit α-amylase, while F4, which contained prenylated flavonoids and furanoflavonoids, was the most active against the tested bacteria. The gathered results emphasize the distinct biological potentials of purified fractions of Retama raetam. 相似文献
133.
Rim G.-H. Lee H.-S. Pavlov E.P. Kim G.-H. Cho C.-H. Choi Y.-W. Kim J.-S. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(5):1362-1367
Many pulsed power applications require short high-voltage pulses with a high-repetition rate. Conventional high-voltage discharge pulse-switches such as thyratrons, spark gap switches, and vacuum tube switches have a short lifetime, whereas the semiconductor switches have a long lifetime and high reliability. The semiconductor switches, however cannot be directly applied to fast high-voltage pulsed power generation due to their limited operating voltage ratings despite their relatively long switching times. Therefore, they are used with voltage amplification and a pulse compression stage. This paper describes two pulse generators that use the semi-conductor switches and nonlinear capacitors: one is based on an opening switch (IGBT) and inductive energy storage, the other is a combination of a closing switch (RSD) and capacitive energy storage 相似文献
134.
On the setting of the half-spaceR
n–1×R
+, we investigate Gleason's problem for harmonic Bergman and Bloch functions. We prove that Gleason's problem for the harmonicL
p
-Bergman space is solvable if and only ifp>n. We also prove that Gleason's problem for the harmonic (little) Bloch space is solvable. 相似文献
135.
Oh CR Choo DJ Shim WH Lee DH Roh EJ Lee SG Song CE 《Chemical communications (Cambridge, England)》2003,(9):1100-1101
In the chiral Co(III)(salen)-catalysed HKR of racemic epoxides, in the presence of ionic liquids, Co(II)(salen) complex is oxidised without acetic acid to catalytically active Co(III)(salen) complex during reaction and, moreover, this oxidation state is stabilised against reduction to Co(II) complex which enables the reuse of the recovered catalyst for consecutive reactions without extra reoxidation. 相似文献
136.
Lee N Cho HR Oh MH Lee SH Kim K Kim BH Shin K Ahn TY Choi JW Kim YW Choi SH Hyeon T 《Journal of the American Chemical Society》2012,134(25):10309-10312
Multimodal imaging is highly desirable for accurate diagnosis because it can provide complementary information from each imaging modality. In this study, a sol-gel reaction of tantalum(V) ethoxide in a microemulsion containing Fe(3)O(4) nanoparticles (NPs) was used to synthesize multifunctional Fe(3)O(4)/TaO(x) core/shell NPs, which were biocompatible and exhibited a prolonged circulation time. When the NPs were intravenously injected, the tumor-associated vessel was observed using computed tomography (CT), and magnetic resonance imaging (MRI) revealed the high and low vascular regions of the tumor. 相似文献
137.
Jong Seung Kim Jeong Ah Rim Ok Jae Shon Kwan Ho Noh Eun-Hee Kim Chaejoon Cheong Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2002,43(1-2):51-54
A series of N-pivot calix[4]crown-5-azacrown-5 ethers substituted by 2-picolyl, 3-picolyl and benzyl groups respectively were synthesized. The nitrogen atom of the 2-picolyl group is found to participate in the silver ion complexation through three dimensional encapsulation. 相似文献
138.
Shin EC Seong YR Kim CH Kim H Ahn YS Kim K Kim SJ Hong SS Park JH 《Experimental & molecular medicine》2002,34(2):114-122
TNF-related apoptosis-inducing ligand (TRAIL), a member of the TNF family, selectively induce apoptosis in various transformed cell lines but not in almost-normal tissues. It is regulated by 2 death receptors, TRAIL receptor 1 (TRAIL-R1) and TRAIL-R2 and 2 decoy receptors, TRAIL-R3 and TRAIL-R4. However, the determining factors of the sensitivity to TRAIL-induced apoptosis are not clearly understood. Herein, we investigated the expression of TRAIL-R, c-FLIP, FADD-like interleukin-1beta-converting enzyme inhibitory protein, and TRAIL-induced apoptosis in human hepatocellular carcinoma (HCC) cell lines. Seven of ten HCC cell lines showed resistance to TRAIL-induced apoptosis and five of seven TRAIL-resistant cell lines became sensitive to TRAIL by co-treatment with cycloheximide. In HCC cell lines, their TRAIL resistance did not correlate with the basal expression level of TRAIL receptors or c-FLIP, however, in human tissues, TRAIL-R1 and TRAIL-R2 expressions were notably decreased compared to normal counterpart. Cisplatin showed synergistic effect on TRAIL-induced apoptosis in most HCC cell lines regardless of their p53 status and TRAIL-R1 was induced by cisplatin treatment in certain cell lines. Inhibition of nuclear factor K B (NF-kappaB) by SN50, a peptide inhibitor of NF-KB activity, had no effect on TRAIL-induced apoptosis in HCC cells. These results suggest that (a) the majority of human HCC cell lines are resistant to TRAIL-induced apoptosis and cycloheximide-sensitive short-lived antiapoptotic molecule(s) is responsible for this resistance, (b) the expression of TRAIL-R1 and TRAIL-R2 is reduced in HCC tissues, and the increased expression of TRAIL-R1 may be a mechanism of cisplatininduced sensitization to TRAIL-induced apoptosis in some HCC cells, and (c) the activation of NF-kappaB may not be involved in the TRAIL resistance of HCC cells 相似文献
139.
140.