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Aeromonas sp. B-5, which has the ability to decolorize azo dyes, was isolated from soil. Aeromonas sp. B-5 completely decolorized 100 mg/l of Bordeaux S by reductive cleavage of azo bonds under static conditions in 24 h. Though the decolorization of Bordeaux S by Aeromonas sp. B-5 was suppressed under shaking, rapid decolorization was observed when the culture was changed to static conditions after cultivation with shaking. The indigoid dye, Acid blue 74, was decolorized by Aeromonas sp. B-5 under shaking conditions, in contrast to the decolorization of azo dyes.  相似文献   
64.
Because rapid and uniform laser heating can fix the neck-drawing point in continuous drawing of PTT fiber, we have successfully analyzed the fiber structure development in the continuous drawing process by in-situ measurement with a time resolution of less than 1 ms. In this study, we investigated fiber structure development for PTT around the neck point controlled with a CO2 laser-heated apparatus during continuous drawing, through on-line measurements of WAXD, SAXS, and fiber temperature. Fiber temperature attained by laser radiation initiated a rise around −3 mm in relation to the neck point at 0 mm, and increased to about 90 °C, which is past the 45 °C Tg for PTT. The instantaneous increase in fiber temperature continued with a vertical ascent, with plastic deformation around the neck point. The crystalline diffraction pattern was revealed initially at the elapsed time of 0.415 ms immediately after necking, and remained fairly constant with elapsed time. The ultimate crystalline diffraction pattern for a completely drawn fiber showed little difference from that at the initial stage. In PET a two-dimensionally ordered structure in the form of a mesophase was detected immediately after the necking, whereas in PTT the phenomenon was not observed. With elapsed time, the d spacing of (002) plane decreased gradually due to transformation of the initial all-trans conformation into trans-gauche-gauche-trans conformation, and ultimately the PTT molecular chain could favorably adopt the trans-gauche-gauche-trans conformation. SAXS pattern immediately after the necking revealed an X-shape; the scattering intensity concentrated on meridian directions due to individual crystal development, and at 2 ms two-pointed scattering started to appear. Past 8 ms, the typical two-pointed scattering pattern was prominent and its intensity increased with elapsed time. Long period decreased with increasing elapsed time, but the crystallite size of meridian (002) plane hardly changed. The decrease in long period might be caused by chain relaxation in the amorphous region.  相似文献   
65.
Dense BaTiO3 ceramics consisting of submicrometer grains were prepared using the spark plasma sintering (SPS) method. Hydrothermally prepared BaTiO3 (0.1 and 0.5 µm) was used as starting powders. The powders were densified to more than similar/congruent95% of the theoretical X-ray density by the SPS process. The average grain size of the SPS pellets was less than similar/congruent1 µm, even by sintering at 1000-1200°C, because of the short sintering period (5 min). Cubic-phase BaTiO3 coexisted with tetragonal BaTiO3 at room temperature in the SPS pellets, even when well-defined tetragonal-phase BaTiO3 powder was sintered at 1100° and 1200°C and annealed at 1000°C, signifying that the SPS process is effective for stabilizing metastable cubic phase. The measured permittivity was similar/congruent7000 at 1 kHz at room temperature for samples sintered at 1100°C and showed almost no dependence on frequency within similar/congruent100-106 Hz; the permittivity at 1 MHz was 95% of that at 1 kHz.  相似文献   
66.
Fe-substituted Li2MnO3 (Li1+x(FeyMn1−y)1−xO2, 0 ≤ x ≤ 1/3, 0.3 ≤ y ≤ 0.7) was synthesized using a combination of coprecipitation, hydrothermal, and heat-treatment methods. It exhibits high initial specific capacity greater than 200 mAh g−1 and small capacity, which fades up to the 50th cycle (>150 mAh g−1 at the 50th cycle) under electrochemical cycle testing at 60 °C. The attractive electrode properties appeared by controlling the chemical composition (x > 0.05, 0.3 ≤ y ≤ 0.5) and high specific surface area (>20 m2 g−1). The Fe-substituted Li2MnO3 is an attractive candidate as a novel 3 V-class positive electrode material.  相似文献   
67.
IntroductionThe s up ersonic- combus t ion ram j et (s cramj et ) engine is one of the most prollilsing air breathing prOPulsion systems for hypersonic transports. It is essentialto the design of scramjet engines that the fueLair miX-ture remains supersonic throughout the combustor.The subsonic combustion is better than the supersonic combustion from a standpoint of efficiency, bescause total pressure losses in heated supersonic flowsare higher than those in heated subsonic flows withsame st…  相似文献   
68.
The glial cells in the central nervous system express diverse inward rectifying potassium channels (Kir). They express multiple Kir channel subtypes that are likely to have distinct functional roles related to their differences in conductance, and sensitivity to intracellular and extracellular factors. Dysfunction in a major astrocyte potassium channel, Kir4.1, appears as an early pathological event underlying neuronal phenotypes in several neurological diseases. The autoimmune effects on the potassium channel have not yet been fully described in the literature. However, several research groups have reported that the potassium channels are an immune target in patients with various neurological disorders. In 2012, Srivastava et al. reported about Kir4.1, a new immune target for autoantibodies in patients with multiple sclerosis (MS). Follow-up studies have been conducted by several research groups, but no clear conclusion has been reached. Most follow-up studies, including ours, have reported that the prevalence of Kir4.1-seropositive patients with MS was lower than that in the initial study. Therefore, we extensively review studies on the method of antibody testing, seroprevalence of MS, and other neurological diseases in patients with MS. Finally, based on the role of Kir4.1 in MS, we consider whether it could be an immune target in this disease.  相似文献   
69.
Cerebral amyloid angiopathy (CAA) is characterized by accumulation of amyloid β (Aβ) in walls of leptomeningeal vessels and cortical capillaries in the brain. The loss of integrity of these vessels caused by cerebrovascular Aβ deposits results in fragile vessels and lobar intracerebral hemorrhages. CAA also manifests with progressive cognitive impairment or transient focal neurological symptoms. Although development of therapeutics for CAA is urgently needed, the pathogenesis of CAA remains to be fully elucidated. In this review, we summarize the epidemiology, pathology, clinical and radiological features, and perspectives for future research directions in CAA therapeutics. Recent advances in mass spectrometric methodology combined with vascular isolation techniques have aided understanding of the cerebrovascular proteome. In this paper, we describe several potential key CAA-associated molecules that have been identified by proteomic analyses (apolipoprotein E, clusterin, SRPX1 (sushi repeat-containing protein X-linked 1), TIMP3 (tissue inhibitor of metalloproteinases 3), and HTRA1 (HtrA serine peptidase 1)), and their pivotal roles in Aβ cytotoxicity, Aβ fibril formation, and vessel wall remodeling. Understanding the interactions between cerebrovascular Aβ deposits and molecules that accumulate with Aβ may lead to discovery of effective CAA therapeutics and to the identification of biomarkers for early diagnosis.  相似文献   
70.
Energetic efficiency is an important indicator of cardiac function in acute myocardial infarction. However, the relationship between cardiac energetic efficiency and infarct size is not perfectly elucidated. In this study, the relationship is analysed by means of simulation using a theoretical model of the guinea pig left ventricle. In simulation with varied ratios of infarct area, pressure–volume area (PVA), which is an index of total mechanical energy by ventricular contraction, and myocardial oxygen consumption (MVO2) are calculated for each infarct ratio. Then, change of PVA when MVO2 alters (PVA/MVO2) as a well‐known index of energy conversion efficiency is evaluated. In addition, PVA/VO2, which represents a ratio of PVA change to alteration of mean oxygen consumption of myocytes except for infarct myocytes, is introduced as an index for real energetic efficiency. In simulation results, PVA/MVO2 increases but PVA/VO2 decreases as infarct area expands, because with expansion of infarct area PVA decreases but VO2 remains almost unchanged because of larger shortening of myocytes. This implies that the enlargement of shortening of noninfarcted myocyte to compensate for depression of cardiac output is a potential cause of myocardial remodelling.Inspec keywords: blood vessels, cardiology, cellular biophysics, haemodynamics, muscle, oxygen, physiological modelsOther keywords: theoretical analysis, left ventricular energetic efficiency, acute infarct size, cardiac function, acute myocardial infarction, cardiac energetic efficiency, guinea pig left ventricle, pressure‐volume area, total mechanical energy, ventricular contraction, myocardial oxygen consumption, energy conversion efficiency, myocyte mean oxygen consumption, infarct myocytes, energetic efficiency index, noninfarcted myocyte shortening enlargement, cardiac output, myocardial remodellingInspec keywords: blood vessels, cardiology, cellular biophysics, haemodynamics, muscle, oxygen, physiological modelsOther keywords: theoretical analysis, left ventricular energetic efficiency, acute infarct size, cardiac function, acute myocardial infarction, cardiac energetic efficiency, guinea pig left ventricle, pressure‐volume area, total mechanical energy, ventricular contraction, myocardial oxygen consumption, energy conversion efficiency, myocyte mean oxygen consumption, infarct myocytes, energetic efficiency index, noninfarcted myocyte shortening enlargement, cardiac output, myocardial remodelling  相似文献   
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