To correct the S-distortion in large deflection angle cathode-ray tubes （CRTs）,ideal deflection current waveforms are proposed to realize S-correction.Analysis was done for homogenous and non-homogenous magnetic fie...To correct the S-distortion in large deflection angle cathode-ray tubes （CRTs）,ideal deflection current waveforms are proposed to realize S-correction.Analysis was done for homogenous and non-homogenous magnetic fields, plane and curved screen.For the convenience of circuit design,high order sine waveforms are used to approach the ideal deflection current.After optimization,the deflection current is acceptably close to the ideal one,for a deflection angle range from 90° up to 140°.Harmonic current rank rises to four as the deflection angle reaches 140°.A ladder-type driving circuit to realize these sine wave series is also presented.Simulation and experiments prove the proposed method can correct the S-distortion in a very slim CRT.展开更多
AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by im...AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 μg of plasmid DNA encoding an EGFP- VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array. RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressedimmunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene- array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhotic rats. Therefore, it may be a good choice for treating hepatic cirrhosis and portal hypertension.展开更多
This paper consists of two parts. In part I, we interpret the hidden symmetry of the moduli space of lib superstring on AdS5× S^5 in terms of the chiral embedding in AdS5, which turns out to be the CP^3 conformal...This paper consists of two parts. In part I, we interpret the hidden symmetry of the moduli space of lib superstring on AdS5× S^5 in terms of the chiral embedding in AdS5, which turns out to be the CP^3 conformal affine Toda model. We review how the position μ of poles in the Riemann-Hilbert formulation of dressing transformation and the value of loop parameter μ in the vertex operator of affine algebra determine the moduli space of the soliton solutions, which describes the moduli space of the Green-Schwarz superstring. We show also how this affine SU（4） symmetry affinizes the conformal symmetry in the twistor space, and how a soliton string corresponds to a Robinson congruence with twist and dilation spin coefficients μ of twistor. In part Ⅱ by extending the dressing symmetric a.ction of lib string in AdS5×S^5 to the D3 brane, we find a gauged WZW aztion of Higgs Yang-Mills field including the 2-cocycle of axially anomaly. The left and right twistor structures of left and right a-planes glue into an ambitwistor. The symmetry group of Nahm equations is centrally extended to an affine group, thus we explain why the spectral curve is given by affine Toda.展开更多
The holomorphic factorization of the superstring partition function is verified at arbitrary genus. The evaluation of scattering amplitudes and the implications of genus-dependent estimates on the string coupling are ...The holomorphic factorization of the superstring partition function is verified at arbitrary genus. The evaluation of scattering amplitudes and the implications of genus-dependent estimates on the string coupling are given.展开更多
文摘To correct the S-distortion in large deflection angle cathode-ray tubes （CRTs）,ideal deflection current waveforms are proposed to realize S-correction.Analysis was done for homogenous and non-homogenous magnetic fields, plane and curved screen.For the convenience of circuit design,high order sine waveforms are used to approach the ideal deflection current.After optimization,the deflection current is acceptably close to the ideal one,for a deflection angle range from 90° up to 140°.Harmonic current rank rises to four as the deflection angle reaches 140°.A ladder-type driving circuit to realize these sine wave series is also presented.Simulation and experiments prove the proposed method can correct the S-distortion in a very slim CRT.
基金The National Natural Science Fundation of China, No. 30300341The Natural Science Fundation of Shandong Province, No. Y2004Z12
文摘AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 μg of plasmid DNA encoding an EGFP- VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array. RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressedimmunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene- array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhotic rats. Therefore, it may be a good choice for treating hepatic cirrhosis and portal hypertension.
基金The project supported by National Natural Science Foundation of China under Grant No. 90403019
文摘This paper consists of two parts. In part I, we interpret the hidden symmetry of the moduli space of lib superstring on AdS5× S^5 in terms of the chiral embedding in AdS5, which turns out to be the CP^3 conformal affine Toda model. We review how the position μ of poles in the Riemann-Hilbert formulation of dressing transformation and the value of loop parameter μ in the vertex operator of affine algebra determine the moduli space of the soliton solutions, which describes the moduli space of the Green-Schwarz superstring. We show also how this affine SU（4） symmetry affinizes the conformal symmetry in the twistor space, and how a soliton string corresponds to a Robinson congruence with twist and dilation spin coefficients μ of twistor. In part Ⅱ by extending the dressing symmetric a.ction of lib string in AdS5×S^5 to the D3 brane, we find a gauged WZW aztion of Higgs Yang-Mills field including the 2-cocycle of axially anomaly. The left and right twistor structures of left and right a-planes glue into an ambitwistor. The symmetry group of Nahm equations is centrally extended to an affine group, thus we explain why the spectral curve is given by affine Toda.
文摘The holomorphic factorization of the superstring partition function is verified at arbitrary genus. The evaluation of scattering amplitudes and the implications of genus-dependent estimates on the string coupling are given.
