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    Parity-violating πNN\pi NN coupling constant from the flavor-conserving effective weak chiral Lagrangian

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    We investigate the parity-violating pion-nucleon-nucleon coupling constant hπNN1h^1_{\pi NN}, based on the chiral quark-soliton model. We employ an effective weak Hamiltonian that takes into account the next-to-leading order corrections from QCD to the weak interactions at the quark level. Using the gradient expansion, we derive the leading-order effective weak chiral Lagrangian with the low-energy constants determined. The effective weak chiral Lagrangian is incorporated in the chiral quark-soliton model to calculate the parity-violating πNN\pi NN constant hπNN1h^1_{\pi NN}. We obtain a value of about 10710^{-7} at the leading order. The corrections from the next-to-leading order reduce the leading order result by about 20~\%.Comment: 12 page

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    Characteristics of injury of the corticospinal tract and corticoreticular pathway in hemiparetic patients with putaminal hemorrhage

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    BACKGROUND: No study on the characteristics of injury of the corticospinal tract (CST) or corticoreticular pathway (CRP) in patients with putaminal hemorrhage has been reported. In this study, using diffusion tensor tractography, we attempted to investigate the characteristics of injury of the CST and CRP in hemiparetic patients with putaminal hemorrhage. METHOD: Fifty seven consecutive patients with putaminal hemorrhage and 57 healthy control subjects were recruited for this study. Diffusion tensor imaging was performed during the early period (8 ~ 30 days) after onset. We defined injury of the CST or CRP in terms of the configuration (discontinuation of a neural tract) or abnormal DTT parameters (the fractional anisotrophy value or fiber number was more than two standard deviations lower than that of normal control subjects). The Motricity Index, the modified Brunnstrom Classification, and the Functional Ambulation Categories were used for evaluation of motor function. RESULTS: Among 57 patients, injury of the CST was found in 41 patients (71.9%) and injury of the CRP was found in 50 patients (87.8%), respectively, and 37 patients (64.9%) had injury of both the CST and CRP. All three motor functions of patients with injury of both the CST and CRP were significantly lower than those of patients with injury of either the CST or CRP (p < 0.05). CONCLUSION: Our results indicate that the putaminal hemorrhage frequently accompanies injury of both the CST and CRP, and the CRP appears to be more vulnerable to putaminal hemorrhage than the CST. These findings suggest the necessity for evaluation of both the CRP and the CST in patients with putaminal hemorrhage
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