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排序方式: 共有249条查询结果,搜索用时 390 毫秒
31.
Jin Kono Masakatsu Ueda Atsushi Sengiku Sylvia O. Suadicani Osamu Ogawa Hiromitsu Negoro 《International journal of molecular sciences》2021,22(4)
Connexin43 (Cx43), the main gap junction and hemichannel forming protein in the urinary bladder, participates in the regulation of bladder motor and sensory functions and has been reported as an important modulator of day–night variations in functional bladder capacity. However, because Cx43 is expressed throughout the bladder, the actual role played by the detrusor and the urothelial Cx43 is still unknown. For this purpose, we generated urothelium-specific Cx43 knockout (uCx43KO) mice using Cre-LoxP system. We evaluated the day–night micturition pattern and the urothelial Cx43 hemichannel function of the uCx43KO mice by measuring luminal ATP release after bladder distention. In wild-type (WT) mice, distention-induced ATP release was elevated, and functional bladder capacity was decreased in the animals’ active phase (nighttime) when Cx43 expression was also high compared to levels measured in the sleep phase (daytime). These day–night differences in urothelial ATP release and functional bladder capacity were attenuated in uCx43KO mice that, in the active phase, displayed lower ATP release and higher functional bladder capacity than WT mice. These findings indicate that urothelial Cx43 mediated ATP signaling and coordination of urothelial activity are essential for proper perception and regulation of responses to bladder distension in the animals’ awake, active phase. 相似文献
32.
Ionic liquid-type polymer brushes having different hydrocarbon (HC) chain lengths between polymerizable group and imidazolium ring were synthesized. When the carbon number of HC chain was 6, the ionic liquid-type polymer brush exhibited the highest ionic conductivity of 1.37×10−4 S cm−1 at 30 °C, reflecting low Tg of −60 °C. Moreover, for the first time, we succeeded in obtaining transparent and flexible films without considerable decrease in the ionic conductivity as compared with that of corresponding monomers by using suitable cross-linkers. The most ion conductive (1.1×10−4 S cm−1 at 30 °C) film was obtained when tetra(ethylene glycol)diacrylate was used 0.5 mol% to ionic liquid monomer as the cross-linker. This film is one of excellent conductive films among single-ion conductive materials. 相似文献
33.
An algorithm for improving the reliability of detection with processing of multiple sensors''signal 总被引:3,自引:0,他引:3
Recent surveys show that most of the false alarms of fire alarm systems are given by deceptive phenomena caused by human actions, such as cigarette smoking and cooking. Software-controlled systems have a potential ability in increasing the reliability of detection signals by data processing. However, it is rather difficult to distinguish an early stage fire from those deceptive phenomena only by processing the data of a single sensor. The authors' new algorithm utilizes the signals from three different sensors, i.e. temperature, smoke and gas (CO) concentration. Incorporating a mathematical fire model, these signals are translated into source parameters such as heat release rate, and smoke and gas generation rates. The conditions of the fire are then analyzed using the cross-correlation function between these source parameters. Testing the algorithm has been done using some experimental data and a promising result has been obtained. 相似文献
34.
Connection of Vortices Between Spatially Different Phases in Two-Component Bose-Einstein Condensates
Kenichi Kasamatsu Hiromitsu Takeuchi Muneto Nitta Makoto Tsubota 《Journal of Low Temperature Physics》2010,158(1-2):99-104
We study interfacial topological defects called boojums, a vortex ending or a connecting point of two kinds of vortex cores, in rotating two-component Bose-Einstein condensates. First, we show that the boojum exists at a vortex ending that connects to the interface of the strongly phase-separated condensates. Next, we study various boojums appearing between two phases characterized by different vortex structures, where the intercomponent s-wave scattering lengths are spatially varied. Using three-dimensional simulations of the Gross-Pitaevskii equations, we reveal the detailed structure of the boojums by visualizing its density distribution and effective superflow vorticity. 相似文献
35.
Kai Shi Fude Cui Hiromitsu Yamamoto Yoshiaki Kawashima 《Drug development and industrial pharmacy》2013,39(2):177-184
A novel poly(lactic acid-co-glycolic acid) nanoparticle loaded with insulin–lauryl sulfate complex was prepared by spontaneous emulsion solvent diffusion method. The effects of key parameters such as agitation speed, poly(vinyl alcohol) concentration, solvent composition, polymer concentration, and the volume of external aqueous phase on the properties of the nanoparticles were investigated. To enhance the drug recovery and drug content simultaneously, a response surface methodology with five-level, two-factor central composite design was employed. The weight ratio of polymer to drug and volume ratio of external aqueous phase to solvent phase were selected as controlled factors on account of their interactions found in the monofactorial investigations. The experimental datum allowed the development of quadratic models (p < .05) describing the inter-relationships between the dependent and independent variables. By solving the regression equation, and graphic analyzing the response surface contour and plots, the optimum values of the two factors were determined as 20/1 and 10/1. The optimized conditions led to 89.6% of drug recovery and 4.57% of drug content during nanoparticle preparation. 相似文献
36.
Multiwalled carbon nanotubes on which poly(cyclohexyl methacrylate)s are densely grafted (PCHMA‐CNTs), are synthesized using a modified surface‐initiated atom transfer radical polymerization technique. The electrical resistance of PCHMA‐CNT is systematically characterized under direct current (DC) and alternating current and compared to that of conventional nanocomposites prepared by blending PCHMA with the CNT (PCHMA/CNT). At a comparable volume fraction of CNT, DC volume resistivity of PCHMA‐CNT is 14 orders of magnitude higher than that of PCHMA/CNT. This is because the grafted polymer with a combination of the high molecular weight and the high grafting density isolates individual CNTs at a long distance in the PCHMA‐CNT system. In addition, impedance analysis reveals that the highly insulated PCHMA‐CNT has the same electrical nature as neat PCHMA, i.e., it is a dielectric. Furthermore, dynamic mechanical analysis shows PCHMA‐CNT has a good mechanical properties as well as ultrahigh electrical resistance. 相似文献
37.
Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures 总被引:1,自引:0,他引:1
38.
Modeling of hydrogen vacancy for dissociative adsorption of H2 on Pd (1 1 1) surface by a quantum chemical molecular dynamics 总被引:1,自引:0,他引:1
39.
Kyuya Nakagawa Hiromitsu Nagao Suvimol Surassmo Sang-Gi Min Mi-Jung Choi 《Drying Technology》2013,31(4):416-424
Microcapsules are of great interest to the food and pharmaceutical industries as vehicles to deliver active ingredients to the gastrointestinal tract. Drying plays an important role in stabilizing microcapsules to prolong their lifetime; however, drying often produces undesirable changes in the microcapsules, such as irreversible aggregation of the microcapsules and activity loss of the encapsulated ingredient. In this work, poly(epsilon-caprolactone) microcapsules containing a model bioactive compound (tocopherol) were prepared and stabilized in a freeze-dried gelatin matrix. This dried product was rehydrated and the aqueous redispersibility of the microcapsules and the tocopherol activity were investigated. The experimental results suggested that a kinetic balance between dehydration (caused by freezing) and gel network formation is a critical factor that affects the redispersibility and ingredient activity of the products. It was further suggested that a hydrogel-based product could be strategically freeze dried to maximize product quality by tuning its freezing process; that is, by employing a controllable dehydration process. 相似文献
40.
The pitch of the spiral finned tube influences seriously to the acoustic resonance in the heat exchanger.In this research,the flow characteristics in relating to the aeolian tone from the finned cylinder are studied by the numerical simulation.It is observed that the tonal noise generated from the finned tube at two pitch spaces.The ratio of the fin pitch to the cylinder diameter is changed at 0.11 and 0.27.The tone level increases and the frequency decreases with the pitch shorter.The separation flow from the cylinder generates the span-wise vortices,Karman vortices,and the separation flow from the fin generates the stream-wise vortices.When the fin pitch ratio is small,the stream-wise vortices line up to span-wise and become weak rapidly.Only the Karman vortices are remained and integrate in span.So the Karman vortex became large.This causes the low frequency and the large aeolian tone. 相似文献