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121.
122.
Gabriel Nagy 《K-Theory》2000,19(1):47-108
A new framework for bivariant K-theory is developed. Various types of homology-cohomology theories are discussed. Our techniques can be used for producing natural elements in E-theory out of continuous fields with non-isomorphic fibers. An alternative definition for the Kasparov product in E-theory is proposed. 相似文献
123.
FAN Hong-Yi WANG Ji-Suo 《理论物理通讯》2006,46(5):935-937
By making the analogy between the operator Hamiltonians of a mesoscopic ring carrying the persistent current and a Josephson junction we have introduced a phase operator and entangled state representation to establish a theoretical formalism for the ring system. 相似文献
124.
Asymptotic Expansions for Closed Orbits in Homology Classes 总被引:3,自引:0,他引:3
In this paper, we study the behaviour of the counting function associated to the closed geodesics lying in a prescribed homology class on a compact negatively curved manifold. Our main result is an asymptotic expansion. We also obtain results in the wider context of periodic orbits of Anosov flows. 相似文献
125.
谈谈与图有关的几种复形的同调群 总被引:2,自引:0,他引:2
我们从组合拓扑方法在图论的应用中,着重介绍与图有关的几种复形的近期研究动态,论述其中一些基础性的问题,并提出一些可供研究的新问题。 相似文献
126.
王立庆 《数学年刊A辑(中文版)》2001,(5)
本文讨论了关于 Waldhausen范畴的K理论与循环同调理论的联系.主要是推广了 Dennis迹映射和Jones-Goodwillie Chern映射.证明了迹映射保持各自的乘法结构.最后讨论了双变量的情形. 相似文献
127.
128.
Aranit Harizaj Olivier Q. De Clercq Benedicte Descamps Christian Vanhove Stefaan C. De Smedt Dirk Poelman Ine Lentacker Kevin Braeckmans 《Particle & Particle Systems Characterization》2019,36(11)
Dendritic cell (DC)‐based vaccines for immunotherapy have already achieved promising results in the last decade. To further improve current treatment protocols and enhance the therapeutic outcome, noninvasive in vivo tracking of DCs remains of crucial importance. Persistent luminescent nanoparticles (PLNPs) are inorganic materials which show an afterglow for hours after the optical excitation has ceased. If the afterglow is in the near‐infrared, the emission of injected particles can be tracked in vivo. However, stability and toxicity issues limit the use of bare PLNPs for biological applications. Therefore, appropriate surface functionalization is needed to improve their biocompatibility. In this study, it is demonstrated that near‐infrared light emitting LiGa5O8:Cr3+ nanoparticles can be functionalized with a biocompatible lipid coating which provides them with outstanding stability in biological media. In vitro experiments show efficient uptake, absence of cytotoxicity even at very high particle concentrations, and no adverse effects on the maturation potential of DCs. DCs labeled with lipid‐coated LiGa5O8:Cr3+ nanoparticles injected in mice can be imaged over days, confirming efficient in vivo migration to the popliteal lymph node. Together the results show that lipid coated LiGa5O8:Cr3+ nanoparticles possess excellent possibilities for further use in research and development of DC based vaccines. 相似文献
129.
Xinquan Zhou Guifang Ju Tiansong Dai Yang Li Haoyi Wu Yahong Jin Yihua Hu 《化学:亚洲杂志》2019,14(9):1506-1514
Near‐infrared (NIR) long‐persistent phosphors (LPPs) have emerged as a potential solution for bio‐imaging applications over the past few years. However, there are enormous challenges regarding their in situ application based on their dependence on short‐wavelength excitation. In this paper, we report a multi‐spectral excited NIR LPP, Li5Zn8Ga5Ge9O36: 1.5 % Cr3+, 0.5 % Ti4+, which overcomes the limitations of functional processes in biological tissues and other complex systems. This LPP exhibits a high luminescent intensity and a long emission duration in the NIR region (700–800 nm). The applicability of this phosphor to tissue imaging is demonstrated experimentally. Its persistent luminescence (PersL) can easily penetrate approximately 2 mm of pork flesh. More importantly, this phosphor can be re‐charged in situ using a red LED or laser diode array to provide renewed NIR PersL for biological tissues, which is beneficial for long‐term biological tissue imaging applications with high signal‐to‐noise ratios. Systematic investigations of the nature of energy traps and PersL mechanisms are also reported in this paper. 相似文献
130.
The extension of the theory of boundary-value problems to ordinary differential equations and inclusions with discontinuous right-hand sides based on the construction of a new version of the method of shifts along trajectories is continued. 相似文献