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41.
Kazuo Akutagawa 《Mathematische Zeitschrift》2003,243(1):85-98
For a supergroup , we describe an obstruction to the existence of positive scalar curvature metrics with minimal boundary condition on a compact
n-dimensional -manifold W with nonempty boundary M, , in terms of the bordism class [M] in the Stolz obstruction group associated to [St2]. In par ticular, when W is a 5-dimensional spin manifold and the -invariant of a connected component of M is nonzero, we prove that W does not admit a positive scalar curvature metric with minimal boundary condition.
Received: 4 July 2001; in final form: 5 February 2002 / Published online: 8 November 2002
RID="*"
ID="*" Partially supported by the Grants-in-Aid for Scientific Research (C), Japan Society for the Promotion of Science, No.
11640070. 相似文献
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Ruxing Fu Hongjun Li Ruoxin Li Kyle McGrath Gianpietro Dotti Zhen Gu 《Advanced functional materials》2021,31(44):2009489
Chimeric antigen receptor (CAR) T cells exhibit promising results for cancer immunotherapy. However, the clinical success is still restricted to certain types of blood cancers, while in solid tumors the clinical activity is modest and potential toxicities remain a concern. There are various barriers that prevent CAR T cells from combating solid tumors. Therefore, distinct strategies have been explored to augment CAR T cell proliferative capacity, persistence, and effector function. Altering the tumor microenvironment, and in particular its physiochemical properties and immunosuppressive milieu, is of great significance to facilitate CAR T cell therapy. In this article, emerging strategies implemented to overcome the barriers of CAR T cell therapy in solid tumors are reviewed. Enhancing infiltration, activation, and persistence of CAR T cells has been addressed in several preclinical models. The future development of this field to promote innovation and clinical translation is also discussed. 相似文献
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Thibault Colombani Loek J. Eggermont Stephen M. Hatfield Zachary J. Rogers Mahboobeh Rezaeeyazdi Adnan Memic Michail V. Sitkovsky Sidi A. Bencherif 《Advanced functional materials》2021,31(37):2102234
Solid tumors are protected from antitumor immune responses due to their hypoxic microenvironments. Weakening hypoxia-driven immunosuppression by hyperoxic breathing of 60% oxygen has shown to be effective in unleashing antitumor immune cells against solid tumors. However, efficacy of systemic oxygenation is limited against solid tumors outside of lungs and has been associated with unwanted side effects. As a result, it is essential to develop targeted oxygenation alternatives to weaken tumor hypoxia as novel approaches to restore immune responses against cancer. Herein, injectable oxygen-generating cryogels (O2-cryogels) to reverse tumor-induced hypoxia are reported. These macroporous biomaterials are designed to locally deliver oxygen, inhibit the expression of hypoxia-inducible genes in hypoxic melanoma cells, and reduce the accumulation of immunosuppressive extracellular adenosine. The data show that O2-cryogels enhance T cell-mediated secretion of cytotoxic proteins, restoring the killing ability of tumor-specific cytotoxic T lymphocytes, both in vitro and in vivo. In summary, O2-cryogels provide a unique and safe platform to supply oxygen as a coadjuvant in hypoxic tumors and have the potential to improve cancer immunotherapies. 相似文献
46.
在直拉单晶炉中使用一种减薄型加热器替代原加热器,改变了单晶炉的热场温度分布。通过有限元模拟分析软件对减薄型加热器进行模拟分析,模拟结果指出减薄型加热器对提升单晶拉速、降低单晶炉功耗具有促进作用。通过对比两种加热器装料量,并进行单晶生长对比实验,实验指出,减薄型加热器在引晶、等径、收尾阶段均降低了功耗,提升了拉速。最后,数据分析指出减薄型加热器的经济性比原加热器有一定提升。 相似文献
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弱闭T(N)-模的预零化子的等距映射 总被引:1,自引:0,他引:1
本文刻划了弱闭T(N)-模的预零化子间的等距映射.设u,W分别为由左连续序同态N→~N和N→~N所确定的弱闭T(N)-模, u(?),W(?)分别为u,W的预零化子,Φ为由u(?)到W(?)上的线性等距映射.若(0)*=(0)#=(0),dim(0)+≠1且min{dim(H(?)~H),dim(He(?)^H)}≥2,则存在酉算子Ui,Vi(i=1,2),使得Φ(A)=U1AV*1或Φ(A)=U2A*V2*. 相似文献
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