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In modern cancer therapy the clinical application of platinum‐based drugs is more and more limited by the occurrence of intrinsic or acquired resistances. In this context the potential use of dinuclear platinum complexes in chemotherapy is increasingly relevant. The novel complexes Pd(Bzdpa)Cl2, Pd2(C4H8(dpa)2)Cl4, and Pt2(C4H8(dpa)2)Cl4 allow a direct comparison of mono‐ and dinuclear palladium and platinum complexes respectively deriving from a 2,2′‐dipyridylamine (Hdpa) ligand system. They were characterized by single crystal X‐ray analysis as well as infrared spectroscopy and elemental analysis. The cisplatin analogous mononuclear palladium complex Pd(Bzdpa)Cl2 ( 1 ) (Bzdpa: (2,2′‐dipyridylbenzyl)amine) belongs to a range of 2,2′‐dipyridylamine‐based compounds which were extensively studied in our laboratories. 1 crystallizes in the orthorhombic space group Pna21 with a = 13.722(3), b = 13.457(3), c = 9.483(2), V = 1751.1(6) Å3, and Z = 4. The metal binding motif of 1 was expanded by a flexible butyl‐linker to form the tetradentate C4H8(dpa)2 ligand. The resulting isotypic dinuclear complexes Pd2(C4H8(dpa)2)Cl4·2CH3CN ( 2 ) and Pt2(C4H8(dpa)2)Cl4·2CH3CN ( 3 ) crystallize in the triclinic space group with a = 7.8427(2), b = 8.7940(2), c = 11.7645 (3), α = 79.219(2)°, β = 84.033(2)°, γ = 87.744(2)°, V = 792.58(3) Å3 ( 2 ) and a = 7.831(5), b = 8.814(5), c = 11.817(5), α = 79.271(5)°, β = 83.571(5)°, γ = 88.063(5)°, V = 796.3(8) Å3 ( 3 ), both with one centrosymmetrical molecule in the unit cell.  相似文献   
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We show by numerical simulation as well as by measurements on negative-index metamaterial wedge samples, that the unavoidable stepping of the refraction interface-due to the finite unit-cell size inherent to metamaterials-can give rise to a well-defined diffracted beam in addition to the negatively refracted beam. The direction of the diffracted beam is consistent with elementary diffraction theory; however, the coupling to this higher order beam is much larger than would be the case for a positive index material. The results confirm recent theoretical predictions of enhanced diffraction for negative-index grating surfaces.  相似文献   
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Both the nucellar projection (NP) and endosperm transfer cells (ETC) of the developing barley grain (harvested 8 days after flowering) were isolated by laser capture micro-dissection combined with pressure catapulting. Protein extracts were analyzed by nanoUPLC separation combined with ESI-Q-TOF mass spectrometry. The majority of the ~160 proteins identified were involved in translation, protein synthesis, or protein destination. The NP proteome was enriched for stress defense molecules, while proteins involved in assimilate transport and the mobilization of nutrients were common to both the NP and the ETC. The combined qualitative and quantitative protein profiling allowed for the identification of several proteins showing tissue specificity in their expression, which underlines the distinct biological functions of these two tissues within the developing barley grain.  相似文献   
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Yang T  Mock A  O'Brien JD  Lipson S  Deppe DG 《Optics letters》2007,32(9):1153-1155
We report what is, to the best of our knowledge, the first demonstration of an edge-emitting photonic crystal nanocavity laser that is integrated with a photonic crystal waveguide. This demonstration is achieved with a double-heterostructure photonic crystal nanocavity incorporating an InAs quantum dot active region.  相似文献   
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A global a posteriori error estimate, valid even if uniqueness fails, is obtained for a class of quasilinear elliptic partial differential equations. It is applied to the analysis of finite element methods for such problems, and to a primitive Fourier series method for the stationary Navier-Stokes problem in three dimensions at arbitrary Reynolds number.This research was supported by the National Science Foundation, Grant No. NSF-GP-37069.  相似文献   
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