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61.
Low aerobic capacity is considered to be a risk factor for stroke, while the mechanisms underlying the phenomenon are still unclear. The current study looked into the impacts of different aerobic capacities on early brain injury in a subarachnoid hemorrhage (SAH) model using rats bred for high and low aerobic capacity (high-capacity runners, HCR; low-capacity runners, LCR). SAH was modeled with endovascular perforation in HCR and LCR rats. Twenty-four hours after SAH, the rats underwent behavioral testing and MRI, and were then euthanized. The brains were used to investigate ventricular wall damage, blood–brain barrier breakdown, oxidative stress, and hemoglobin scavenging. The LCR rats had worse SAH grades (p < 0.01), ventricular dilatation (p < 0.01), ventricular wall damage (p < 0.01), and behavioral scores (p < 0.01). The periventricular expression of HO-1 and CD163 was significantly increased in LCR rats (p < 0.01 each). CD163-positive cells were co-localized with HO-1-positive cells. The LCR rats had greater early brain injuries than HCR rats. The LCR rats had more serious SAH and extensive ventricular wall damage that evolved more frequently into hydrocephalus. This may reflect changes in iron handling and neuroinflammation.  相似文献   
62.
International Journal of Steel Structures - Carbon fiber reinforced plastic, CFRP, plates bonding method is one of the new repair methods for fatigue cracks. In this method, propagation of fatigue...  相似文献   
63.
L particles, composed of the L protein of the hepatitis B virus surface antigen, are candidates for a specific gene and drug delivery system. We previously constructed stably transfected insect cells for L particle production. In this study, the cells were successfully immobilized within porous biomass support particles (BSPs) in shake-flask culture. The immobilized cells showed a high specific productivity, comparable to the maximum productivities in static and shake-flask cultures of nonimmobilized cells.  相似文献   
64.
We recently proposed the idea of a novel sort of superconducting detector, i.e., a current-biased kinetic inductance detector (CB-KID). This detector is different from a current-biased transition edge detector studied previously, and is able to sense a change in kinetic inductance \(L_k\) given by \(L_{k} = \Lambda _{k}l/S = m_{s}l/n_{s}{q_{s}}^{2}S\) ( \(\Lambda _{k}\) ; kinetic inductivity, \(m_s\) ; mass of Cooper pair, \(n_s\) ; density of Cooper pairs, \(q_s\) ; charge of Cooper pair, \(l\) ; length of device, \(S\) ; cross sectional area) under a constant dc bias current \(I_b\) . In the present work, we first extend this idea to construct a multi-channel CB-KIDs array made of 200-nm-thick MgB \(_2\) thin-film meanderline with 3- \(\upmu \) m thin wire. We succeeded in observing clear signals for imaging from the four-channel CB-KIDs at 4 K by irradiating focused pulsed laser. A scanning laser spot can be achieved by an XYZ piezo-driven stage and an optical fiber with an aspheric focused lens. We can see typical signals from all 4 channels at 4 K, and obtain the positional dependence of the signal as the contour in XY plane. Our CB-KIDs can be used as neutron detectors by utilizing energy released from a nuclear reaction between \(^{10}\) B and cold neutron.  相似文献   
65.
The CeIrIn5-Ag junctions of about 2×10–9 cm–2 area have been made using microfabrication techniques, and the surface superconducting state of CeIrIn5, which has two characteristic temperatures T 0 and T c, has been investigated, where T 0 and T c are the transition temperature to zero-resistivity state and the bulk, thermodynamic transition temperature, respectively. The temperature, below which superconducting anomalies are observed, varies from junction to junction, and yet it is always well above T c=0.4 K. This result, together with no indication of transition at T c, suggests that at least the surface of CeIrIn5 is in the superconducting state above T c. The data on the critical current I c in superconducting anomalies point to the possibility to define a local transition temperature for each junction.  相似文献   
66.
The two-step postsynthesis method (creation of vacant T-sites and associated SiOH groups by dealumination of BEA zeolite with nitric acid followed by incorporation of copper in the resulting SiBEA by impregnation with an aqueous solution of copper nitrate) allows to obtain a CuSiBEA zeolite which contains 0.8 Cu wt%. The incorporation of Cu(II) into the lattice of SiBEA is evidenced by XRD while the concomitant consumption of SiOH groups is monitored by FTIR. The presence of mainly isolated mononuclear Cu(II) in D2d-distorted tetrahedral symmetry is evidenced by diffuse reflectance UV–vis-NIR, EXAFS and XANES. The CuSiBEA zeolite is active in the selective catalytic reduction (SCR) of NO with ethanol or propane with maximum NO conversion of 40 and 20% and selectivity toward N2 close to 80–90 and 90–100%, respectively. These results suggest that the SCR process occurs on isolated mononuclear Cu(II) in D2d-distorted tetrahedral symmetry after Al atoms have been removed from the zeolite structure. Thus, Cu(II) ions do not need Al atoms in their environment to be catalytically active. The lack of correlation between the SCR activity in presence of ethanol and the oxidation of NO to NO2 suggests that the two reactions are more competitive than sequential. The higher activity of CuSiBEA with ethanol than with propane may be due to different activation energies and/or reaction mechanisms.  相似文献   
67.
We compared the fibrinolytic properties of recombinant staphylokinase (SAK), a fibrin-specific plasminogen activator, with those of streptokinase and tissue-type plasminogen activator (t-PA) by means of the amidolytic method. We also investigated the involvement of alpha 2-macroglobulin, C1-inactivator and alpha 1-antitrypsin in SAK-induced fibrin-specific fibrinolysis. Both SAK and t-PA activated plasminogen efficiently in the presence of fibrin in human plasma. Although t-PA activated plasminogen dependently on fibrin in the reconstituted plasma system, SAK activated plasminogen independently of fibrin without alpha 2-plasmin inhibitor (alpha 2-antiplasmin, alpha 2-PI). These findings suggest that fibrin and alpha 2-PI play important roles in plasminogen activation by SAK but not by t-PA. Furthermore, protease inhibitors such as alpha 2-PI, alpha 2-macroglobulin, C1-inactivator and alpha 1-antitrypsin inhibited plasminogen activation by SAK and the inhibitory actions of these protease inhibitors disappeared in the presence of fibrin. This shows that alpha 2-macroglobulin, C1-inactivator and alpha 1-antitrypsin, other than alpha 2-PI, contribute to the fibrin-specificity of SAK.  相似文献   
68.
In this paper, dual exponential possibility distributions, namely, upper and lower exponential possibility distributions, are identified from the given data to characterize a decision-maker's knowledge. A decision group's knowledge can be represented by a set of such dual possibility distributions. The inherent diversity of knowledge among decision-makers is characterized by a conflict index. A conflict resolution model is proposed based on the conflict index, which integrates multiple possibility distributions identified into a new one to represent compromised knowledge of a decision group. As an application, a portfolio selection problem with multiple decision-makers is considered.  相似文献   
69.
70.
A rapid quenching apparatus employing a laser beam was developed to obtain the glassy state of oxides which have high melting temperatures. Using this apparatus, the glassy state in Ln-Ti-O, Ln-Nb-O and Ln-Ta-O (Ln=lanthanides) systems was investigated. The range of compositions which produced glasses and the crystallization process were studied in detail, and the metastable phases, which appear during the crystallization process, were examined by differential thermal and X-ray diffraction analysis.  相似文献   
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