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991.
A graph G is induced matching extendable if every induced matching of G is included in a perfect matching of G. A graph G is generalized induced matching extendable if every induced matching of G is included in a maximum matching of G. A graph G is claw-free, if G dose not contain any induced subgraph isomorphic to K1,3. The k-th power of G, denoted by Gu, is the graph with vertex set V(G) in which two vertices are adjacent if and only if the distance between them is at most k in G. In this paper we show that, if the maximum matchings of G and G3 have the same cardinality, then G3 is generalized induced matching extendable. We also show that this result is best possible. As a result, we show that if G is a connected claw-flee graph, then G3 is generalized induced matching extendable. 相似文献
992.
993.
2 kW半导体激光加工光源 总被引:3,自引:3,他引:0
针对激光加工在金属材料焊接、熔覆、表面硬化等工业领域的应用,考虑到半导体激光器体积和重量小、效率高、免维护、成本低以及波长较短等特点,设计了功率达2 kW的半导体激光加工光源。在大通道工业水冷条件下,采用48只出射波长分别为808,880,938,976 nm的传导冷却半导体激光阵列作为发光单元,最终研制出了2 218 W高亮度光纤耦合模块。此高亮度模块可以实现柔性加工,直接应用于金属材料焊接、熔覆、表面合金化等工业领域,对于半导体激光器在工业领域的应用具有重要意义。 相似文献
994.
Donghai Zhu Shan Yun Xueying Nai Dongmei Zhao Xin Liu Wu Li 《Crystal Research and Technology》2013,48(1):6-10
Single crystalline strontium chloroborate (Sr2B5O9Cl) whiskers with uniform diameter have been synthesized by a facile route based on the calcination of precursor. The precursor was prepared by the sedimentation reaction between SrCl2 and Na2B4O7 aqueous solution. The products were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectrum (FT‐IR). An optimal synthesis temperature for preparing Sr2B5O9Cl whiskers was obtained, and the possible formation process was also presented. 相似文献
995.
Xiu-Zhong Yao Hong Yun Meng-Su Zeng He Wang Fei Sun Sheng-Xiang Rao Yuan Ji 《Magnetic resonance imaging》2013
Purpose
The objective of this paper was to investigate the value of apparent diffusion coefficients (ADCs) for differential diagnosis among solid pancreatic masses using respiratory triggered diffusion-weighted MR imaging with inversion-recovery fat-suppression technique (RT-IR-DWI) at 3.0 T.Materials and Methods
20 normal volunteers and 72 patients (Pancreatic ductal adenocarcinoma [PDCA, n = 30], mass-forming pancreatitis [MFP, n = 15], solid pseudopapillary neoplasm [SPN, n = 12], and pancreatic neuroendocrine tumor[PNET, n = 15]) underwent RT-IR-DWI (b values: 0 and 600 s/mm2) at 3.0 T. Results were correlated with histopathologic data and follow-up imaging. ADC values among different types of pancreatic tissue were statistically analyzed and compared.Results
Statistical difference was noticed in ADC values among normal pancreas, MFP, PDCA, SPN and PNET by ANOVA (p < .001). Normal pancreas had the highest ADC value, then followed by PNET, PDCA, MFP and SPN. There was noticeable statistical difference in ADC values among PDCA, MFP and normal pancreas by Least Significant Difference (LSD) (p < .001). ADC of SPN was statistically lower than that of PNET (p = 0.1800 × 10− 4), PDCA (p = 0.0300 × 10− 4) and normal pancreas (p = 0.0007 × 10− 4). ADC of PNET was statistically lower than that of normal pancreas (p = 0.0360) and higher than that of MFP (p = 9.3000 × 10− 4).Conclusions
ADC measurements using RT-IR-DWI at 3.0 T may aid to disclose the histopathological pattern of normal pancreas and solid pancreatic masses, which may be helpful in characterizing solid pancreatic lesions. 相似文献996.
997.
Let M n be a complete oriented noncompact hypersurface in a complete Riemannian manifold N n+1 of nonnegative sectional curvature with ${2 \leq n \leq 5}$ . We prove that if M satisfies a stability condition, then there are no non-trivial L 2 harmonic one-forms on M. This result is a generalization of a well-known fact in the case when M is a stable minimally immersed hypersurface. As a consequence, we show that if the mean curvature of M is constant, then either M must have only one end or M splits into a product of ${\mathbb{R}}$ and a compact manifold with nonnegative sectional curvature. In case ${n \geq 5}$ , we also show that the same result holds if the absolute value of the mean curvature is less than or equal to the ratio of the norm of the second fundamental form to the dimension of a hypersurface. 相似文献
998.
Kyunghyun Yoo Hye-Hyeon Yun Soon-Young Jung Jeong-Hwa Lee 《Molecules (Basel, Switzerland)》2021,26(14)
KRIBB11, an HSF1 inhibitor, was shown to sensitize various types of cancer cells to treatment with several anticancer drugs. However, the exclusive effects of KRIBB11 in preventing the growth of glioblastoma cells and the related mechanisms have not been elucidated yet. Herein, we aimed to examine the potential of KRIBB11 as an anticancer agent for glioblastoma. Using MTT and colony formation assays and Western blotting for c-PARP, we demonstrated that KRIBB11 substantially inhibits the growth of A172 glioma cells by inducing apoptosis. At the molecular level, KRIBB11 decreased anti-apoptotic protein MCL-1 levels, which was attributable to the increase in MULE ubiquitin ligase levels. However, the constitutive activity of HSF1 in A172 cells was not influenced by the exclusive treatment with KRIBB11. Additionally, based on cycloheximide chase assay, we found that KRIBB11 markedly retarded the degradation of MULE. In conclusion, stabilization of MULE upon KRIBB11 treatment is apparently an essential step for degradation of MCL-1 and the subsequent induction of apoptosis in A172 cells. Our results have expanded the knowledge on molecular pathways controlled by KRIBB11 and could be potentially effective for developing an inhibitory therapeutic strategy for glioblastoma. 相似文献
999.
In this article, we define a new associative dialgebra over a polynomial algebra F[x, y] with two indeterminates x and y. Left derivations, right derivations, derivations, and automorphisms of F[x, y] as associative dialgebra are determined. Meanwhile, we also determine all homogeneous derivations of F[x, y] as ?-graded Leibniz algebra, and automorphisms of Leibniz algebra F[x, y] preserving the standard filtration. 相似文献
1000.
主要讨论了Hardy-Littlewood极大函数,Sharp极大函数以及分数次极大函数与BMO(R~n)函数生成的交换子在广义Morrey空间上有界性的等价刻画. 相似文献