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21.
In this paper we study autoregressive processes of order 1 with values in a separable Banach space it B. Such ARB(1)-processes are defined by the recursion equation
where T : B → B is a bounded linear operator and m ∈ B. We analyze the asymptotic properties of the sample mean and of the sample covariance operator in case that the innovation process is weakly dependent. This extends earlier results of Bosq (2000, 2002), who studied ARB(1)-processes with independent and orthogonal observations. Research supported by DAAD (German Academic Exchange Service) grant A/01/26875.  相似文献   
22.
A circle graph is the intersection graph of a family of chords on a circle. There is no known characterization of circle graphs by forbidden induced subgraphs that do not involve the notions of local equivalence or pivoting operations. We characterize circle graphs by a list of minimal forbidden induced subgraphs when the graph belongs to one of the following classes: linear domino graphs, P4-tidy graphs, and tree-cographs. We also completely characterize by minimal forbidden induced subgraphs the class of unit Helly circle graphs, which are those circle graphs having a model whose chords have all the same length, are pairwise different, and satisfy the Helly property.  相似文献   
23.
The orphan nuclear receptor 4A1 (NR4A1) is overexpressed in pancreatic cancer and exhibits pro-oncogenic activity, and NR4A1 silencing and treatment with its inactivators has been shown to inhibit pancreatic cancer cells and tumor growth. In this study, we identified broussochalcone A (BCA) as a new NR4A1 inhibitor and demonstrated that BCA inhibits cell growth partly by inducing NR4A1-mediated apoptotic pathways in human pancreatic cancer cells. BCA downregulated specificity protein 1 (Sp1)-mediated expression of an anti-apoptotic protein, survivin, and activated the endoplasmic reticulum (ER) stress-mediated apoptotic pathway. These results suggest that NR4A1 inactivation contributes to the anticancer effects of BCA, and that BCA represents a potential anticancer agent targeting NR4A1 that is overexpressed in many types of human cancers.  相似文献   
24.
In this paper, we first establish a Schwarz?CPick type theorem for pluriharmonic mappings and then we apply it to discuss the equivalent norms on Lipschitz-type spaces. Finally, we obtain several Landau??s and Bloch??s type theorems for pluriharmonic mappings.  相似文献   
25.
Research on Chemical Intermediates - In the current work, an acidic ionic liquid ([{(IMC)-4-OMBH}BIM][HSO4]3) has been utilized as an effective and recyclable catalyst for the synthesis of...  相似文献   
26.
We extend some fundamental spectral properties of classic regular Sturm--Liouville problems to discontinuous boundary-value problems with eigenvalue-dependent boundary conditions. We suggest a new approach for investigation of such type discontinuous problems.  相似文献   
27.
The electron-impact induced rearrangements of halobiphenyls show substituent equilibration in the molecular ion for the chloro, bromo and iodo isomers. The above halo compounds as well as the fluoro, methyl and methoxybiphenyls all show considerable H/D randomization in the molecular ion or some subsequent decomposition ion.  相似文献   
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29.
The effect of Al mole fractions on the structural and electrical properties of AlxGa1−xN/GaN thin films grown by plasma-assisted molecular beam epitaxy (PA-MBE) on Si (1 1 1) substrates has been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and current-voltage (I-V) measurements. X-ray results revealed that the AlGaN/GaN/AlN was epitaxially grown on Si substrate. By applying Vegard's law, the Al mole fractions of AlxGa1−xN samples were found to be 0.11, 0.24, 0.30 and 0.43, respectively. The structural and morphology results indicated that there is a relatively larger tensile strain for the sample with the smallest Al mole fraction; while a smaller compressive strain and larger grain size appear with Al mole fraction equal to 0.30. The strain gets relaxed with the highest Al mole fraction sample. Finally, the linear relationship between the barrier height and Al mole fraction was obtained.  相似文献   
30.
The matching number of a graph is the maximum size of a set of vertex-disjoint edges. The transversal number is the minimum number of vertices needed to meet every edge. A graph has the König–Egerváry property  if its matching number equals its transversal number. Lovász proved a characterization of graphs having the König–Egerváry property by means of forbidden subgraphs within graphs with a perfect matching. Korach, Nguyen, and Peis proposed an extension of Lovász’s result to a characterization of all graphs having the König–Egerváry property in terms of forbidden configurations (which are certain arrangements of a subgraph and a maximum matching). In this work, we prove a characterization of graphs having the König–Egerváry property by means of forbidden subgraphs which is a strengthened version of the characterization by Korach et al. Using our characterization of graphs with the König–Egerváry property, we also prove a forbidden subgraph characterization for the class of edge-perfect graphs.  相似文献   
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