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11.
The problems of charge stripe formation, spin-charge separation, and stability of the antiphase domain wall (ADW) associated with a stripe are addressed using an analytical approach to the t- J(z) model. We show that a metallic stripe together with its ADW is the ground state of the problem in the low doping regime. The stripe is described as a system of spinons and magnetically confined holons strongly coupled to the two dimensional spin environment with holon-spin-polaron elementary excitations filling a one-dimensional band.  相似文献   
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A convenient and efficient procedure for the regioselective ring opening of epoxides in the presence of Dowex (strongly acidic cationic exchange resin), as reusable eco‐friendly catalyst under solvent free conditions is described. Thus, several β‐hydroxy thiocyanates, useful intermediates toward pharmaceutical and biologically active molecules, are easily obtained in high isolated yields.  相似文献   
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Silica sulfuric acid was developed as a stable and efficient heterogeneous catalyst in organic synthesis. This solid acid catalyzed the regioselective ring opening of epoxides by thiocyanate anion to give thiocyanohydrins as key intermediates in agricultural and pharmaceutical chemistry in high yields under solvent-free conditions.  相似文献   
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Background  

This study compared the transduction efficiencies of an adeno-associated viral (AAV) vector, which was pseudotyped with an AAV1 capsid and encoded the green fluorescent protein (GFP), with a lentiviral (LV) vector, which was pseudotyped with a VSV-G envelop and encoded the discosoma red fluorescent protein (dsRed), to investigate which viral vector transduced the lateral hypothalamus or the amygdala more efficiently. The LV-dsRed and AAV1-GFP vector were mixed and injected into the lateral hypothalamus or into the amygdala of adult rats. The titers that were injected were 1 × 108 or 1 × 109 genomic copies of AAV1-GFP and 1 × 105 transducing units of LV-dsRed.  相似文献   
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The equations of magnetostatic equilibria for a plasma in agravitational field are investigated analytically. For equilibriawith an ignorable spatial coordinate, the equations reduce toa single nonlinear elliptic equation for the magnetic potentialu known as the Grad-Shafranov equation. By specifying the arbitraryfunctions in this equation, a Liouville equation is obtained.Bäcklund transformations are described and applied to obtainexact solutions for the Liouville equation modelling an isothermalmagnetostatic atmosphere, in which the current density J isproportional to the exponential of the magnetic potential andmoveover falls off exponentially with distance vertical to thebase with an e-folding distance equal to the gravitational scaleheight.  相似文献   
16.
The high-temperature superconductor with the nominal composition YBa2Cu3O7?σ has been doped with iron 93% enriched in57Fe. When 1.5 at % Fe substitutes for Cu, the transition temperature is reduced by about 30° K with full ac shielding (X′=?1/4π) achieved by ≈40 K. At room temperature the Mössbauer spectrum consists of three overlapping doublets. Below 10 K, hyperfine-field splitting is observed; relaxation still takes place at T=1.8 K.  相似文献   
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Background  

Multiple neuropeptides, sometimes with opposing functions, can be produced from one precursor gene. To study the roles of the different neuropeptides encoded by one large precursor we developed a method to overexpress minigenes and establish local secretion.  相似文献   
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