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[en] Myelin containing in basal ganglia in multiple sclerosis patients was evaluated using new noninvasive quantitative MRI method fast whole brain macromolecular proton fraction mapping. Myelin level in globus pallidus and putamen significantly decreased in multiple sclerosis patients as compared with healthy control subjects but not in substantia nigra and caudate nucleus. (paper)
[en] Light absorption and the subsequent transfer of excitation energy are the first two steps in the photosynthetic process, carried out by protein-bound pigments, mainly bacteriochlorophylls (BChls), in photosynthetic bacteria. BChls are anchored in light-harvesting (LH) complexes, such as light-harvesting complex I (LH1), which directly associates with the reaction center (RC), forming the RC-LH1 core complex. In Rhodobacter sphaeroides, RC-LH1 core complexes contain an additional protein, PufX, and assemble into dimeric RC-LH1-PufX core complexes. In the absence of LH complex II (LH2), the former complexes can aggregate into a helically ordered tubular photosynthetic membrane. We have examined the excitation transfer dynamics in a single RC-LH1-PufX core complex dimer using the hierarchical equations of motion for dissipative quantum dynamics that accurately, yet in a computationally costly manner, treat the coupling between BChls and their protein environment. A widely employed description, the generalized Foerster (GF) theory, was also used to calculate the transfer rates of the same excitonic system in order to verify the accuracy of this computationally cheap method. Additionally, in light of the structural uncertainties in the Rba. sphaeroides RC-LH1-PufX core complex, geometrical alterations were introduced into the BChl organization. It is shown that the energy transfer dynamics are not affected by the considered changes in the BChl organization and that the GF theory provides accurate transfer rates. An all-atom model for a tubular photosynthetic membrane is then constructed on the basis of electron microscopy data, and the overall energy transfer properties of this membrane are computed.
[en] Aim: To explore the value of 64-section computed tomography (CT) perfusion imaging (CTPI) in the early diagnosis of acute radiation-induced lung injury (ARILI). Materials and methods: Fifty-one patients with oesophageal cancers or malignant thymomas received postoperative radiation therapy with a 60–62 Gy dose and underwent CTPI at pre- and post-radiation therapy time points (week 0, week 4, week 8, and week 12 respectively). The CTPI values were prospectively compared and analysed in order to evaluate the diagnostic utility of CTPI in the early diagnosis of ARILI. Results: Eighteen cases (18/51) of ARILI were diagnosed. The mean values of relative regional blood flow (rrBF), relative regional volume (rrBV), and relative regional permeability surface (rrPS) in the ARILI group were correspondingly higher than those of the non-ARILI group. At week 4, rrBF, rrBV, and rrPS in the ARILI group were significantly higher than those at pre-radiation (each p < 0.05). In the non-ARILI group, rrBF and rrBV were higher than those at pre-radiation (each p < 0.05); however, rrPS was not statistically different from that of pre-irradiation. Applying the diagnostic threshold value of rrPS = 1.22, the sensitivity, specificity, and positive and negative predictive values of CTPI for early diagnosis of ARILI were better than those of CT. Conclusion: CTPI metrics may reflect haemodynamic changes in the post-irradiation lung and can detect cases of early ARILI that appear normal at CT. CTPI is a promising technique for early diagnosis of ARILI. - Highlights: • Conventional morphologic imaging (x-ray or CT) is hard to detect the early changes of lungs after thoracic radiotherapy. • CT perfusion imaging metrics may reflect hemodynamic changes in post-irradiation lung. • CT perfusion imaging can detect manifestations of early radiation-induce lung injury cases which appear normal on CT. • CT perfusion imaging is a promising technique for early diagnosis of acute radiation-induce lung injury
[en] The electrochemical behavior of the Fe(III)/Fe(II)-triethanolamine(TEA) complex redox couple in alkaline medium and influence of the concentration of TEA were investigated. A change of the concentration of TEA mainly produces the following two results. (1) With an increase of the concentration of TEA, the solubility of the Fe(III)-TEA can be increased to 0.6 M, and the solubility of the Fe(II)-TEA is up to 0.4 M. (2) In high concentration of TEA with the ratio of TEA to NaOH ranging from 1 to 6, side reaction peaks on the cathodic main reaction of the Fe(III)-TEA complex at low scan rate can be minimized. The electrode process of Fe(III)-TEA/Fe(II)-TEA is electrochemically reversible with higher reaction rate constant than the uncomplexed species. Constant current charge-discharge shows that applying anodic active materials of relatively high concentrations facilitates the improvement of cell performance. The open-circuit voltage of the Fe-TEA/Br2 cell with the Fe(III)-TEA of 0.4 M, after full charging, is nearly 2.0 V and is about 32% higher than that of the all-vanadium batteries, together with the energy efficiency of approximately 70%. The preliminary exploration shows that the Fe(III)-TEA/Fe(II)-TEA couple is electrochemically promising as negative redox couple for redox flow battery (RFB) application