醋酸菌对C57BL/6J小鼠的酒精性肝损伤的影响研究

该文针对摄入醋酸菌对于酒精性肝损伤的影响进行了评价。将C57BL/6J小鼠（8周龄,雄性,22～27 g）分为对照组（非乙醇给药组）、乙醇组（给予2.5 g/kg乙醇）、乙醇+醋酸菌组（给予2.5 g/kg乙醇+10 mg醋酸菌）,分别每天给药3次,连续经口给药14 d,测定了血清谷草转氨酶（AST）、谷丙转氨酶（ALT）及肝脏油脂浓度。结果表明,与对照组相比较,乙醇组小鼠的AST与ALT浓度,肝脏甘油三酯与胆固醇浓度显著增高（P＜0.05）;乙醇+醋酸菌组的数值则显著低于乙醇组（P＜0.05）。以上结果表明,摄入醋酸菌有可能会减轻酒精性肝损伤。     

Solidification of binary aqueous solution cooled from above

Freezing and melting phenomena are important in many different fields, including crystal growth, casting, metallurgy, geophysics, and oceanography. Solidification of a multi‐component solution is the one often observed in nature. In order to investigate basic features of the freezing processes of binary systems, we conducted a series of laboratory experiments in a rectangular box cooled from above using aqueous NaNO₃ solution. During the freezing, the solid phase always grows into many needle‐like crystals called the mushy layer. We measured the growth of the mushy layer thickness, the solid fraction, the temperature, and the concentration distributions. The average solid fraction is found to increase with time in the mushy layer. This causes a slow descent of the released solute in the mushy layer and its eventual fall into the liquid region below because of gravity. We propose a one‐dimensional model to explain the horizontally‐averaged mushy layer growth. In the model, the estimate of a heat flux at the mushy‐liquid interface due to natural convection is found essential for a correct prediction. The proposed theory predicts well the growth of the mushy‐layer and the average solid fraction, once the convective heat flux is properly given. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20278     

Relation between peak structures of loss functions of single double-walled carbon nanotubes and interband transition energies

Electron energy-loss spectra of single double-walled carbon nanotubes (DWCNTs) were compared with calculated joint density of states (jDOSs) obtained by a simple tight-binding (STB) and an extended tight-binding (ETB) method. From the comparisons, interband transition energies of ETB calculations show better agreement with peak positions of the experimental spectra than those of STB results. From a further comparison among calculated jDOS, real and imaginary parts of a dielectric function and a loss function Im[-1/epsilon], it was confirmed that the peak energies in a spectrum of single DWCNTs are almost equal to those of the optical absorption spectrum epsilon(2).     

Optimization of Electric Power Leveling Systems by Taper‐Off‐Reflectance Particle Swarm Optimization

It has become desirable to develop energy control technologies for environmental issues such as global warming and exhaustion of fossil fuel. Power fluctuations in large power consumer facilities may cause instability of electric power systems and increase the cost of the electric power facilities and electricity charges. Developing electric power leveling systems (EPLS) to compensate power fluctuations is necessary for future electric power systems. EPLS with an SMES has been proposed as one countermeasure for use in electric power quality improvement. SMES is superior to other energy storage devices in response and storage efficiency. The authors have proposed EPLS based on fuzzy control with SMES. For this practical implementation, optimizing the control gain and SMES capacity is an important issue. This paper proposes a new method for optimization of the EPLS. The proposed algorithm is a novel particle swarm optimization based on taper‐off reflectance (TRPSO). The proposed TRPSO optimizes the design variables of the EPLS efficiently and effectively. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 10–18, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22472     

Dehydrogenation and Isomerization of n-Butane or Isobutane Over Cr Catalysts Supported on Zeolites

Dehydrogenation and isomerization of n-butane or isobutane into isobutene over Cr catalysts supported on zeolites were investigated. We found that Cr catalyst supported on H-SSZ-35-type zeolite, having one-dimensional cage-type channel structure, was very effective for this reaction and the yield of isobutene was 5.44% from n-butane and 9.57% from isobutane. In this reaction, it is suggested that dehydrogenation of butanes is accelerated by Cr₂O₃ loading, and solid acidity of the zeolite support favors isomerization.     

11 T liquid helium-free superconducting magnet

An 11 T liquid helium-free superconducting magnet designed at 6 K in vacuum using high temperature superconducting current leads was developed. The coil was conductively cooled down from room temperature to 4.1 K in 40 h by two 4 K GM-cryocoolers. In a performance test, the coil temperature rose to 6.8 K for the inner Nb₃Sn coil and 5.9 K for the outer NbTi coil, while sweeping the field at 5 A min⁻¹. A central field of 10.7 T in a 52 mm room temperature bore was generated at an operating current of 149 A. Holding the field at 10.5 T was achieved continuously for 24 h at a constant coil temperature of 4.8 K.     

Transparent VPN failure recovery with virtualization

Cloud computing is widely used to provide today’s Internet services. Since its service scope is being extended to a wide range of business applications, the security of network communications between clients and clouds are becoming important. Several cloud vendors support virtual private networks (VPNs) for connecting their clouds. Unfortunately, cloud services become unavailable when a VPN failure occurred in a VPN gateway or networks. We propose a transparent VPN failure recovery scheme that can hide VPN failures from users and operating systems (OSs). This scheme transparently recovers from VPN failures by establishing VPN connections in a virtualization layer. When a VPN failure occurs, a client virtual machine monitor (VMM) automatically reconnects to an available VPN gateway which is geographically distributed and connected via leased lines in clouds. IP address changes are hidden from client OSs and servers via a packet relay system implemented by a relay client in the client VMM and a relay server. We implemented a prototype system based on BitVisor, a small client VMM supporting IPsec VPN, and evaluated the prototype system in a wide-area distributed Internet environment in Japan. Experimental results show that our scheme can maintain TCP connections on VPN failures, and performance overhead with the virtualization layer is around 0.6 ms to latency and 8%-30% to throughput.     

On some special solutions to periodic Benjamin-Ono equation with discrete Laplacian

We investigate a periodic version of the Benjamin-Ono (BO) equation associated with a discrete Laplacian. We find some special solutions to this equation, and calculate the values of the first two integrals of motion _I1$I_1$ and _I2$I_2$ corresponding to these solutions. It is found that there exists a strong resemblance between them and the spectra for the Macdonald q$q$-difference operators. To better understand the connection between these classical and quantum integrable systems, we consider the special degenerate case corresponding to q=0$q=0$ in more detail. Namely, we give general solutions to this degenerate periodic BO, obtain explicit formulas representing all the integrals of motions _In$I_n$ (n=1,2,…$n=1\text{,}2\text{,}\dots$), and successfully identify it with the eigenvalues of Macdonald operators in the limit q→0$q\to 0$, i.e. the limit where Macdonald polynomials tend to the Hall–Littlewood polynomials.     

Dynamic surface tension and surface dilatational elasticity properties of mixed surfactant/protein systems

We present the study on dynamic surface tension and surface dilatational elasticity properties of dilute aqueous systems of pentaglycerol fatty acid esters (pentaglycerol monostearate, C18G5, and pentaglycerol monooleate, C18:1G5, whey protein, sodium caseinate, and mixed surfactant and protein at room temperature. The adsorption kinetics at the air-liquid interface has been studied by bubble pressure tensiometer and the oscillation bubble (rising drop) method. It has been shown that the dynamic surface tension curve basically presents two-regions; namely induction region and rapid fall region. During the induction time the adsorption is the diffusion-controlled process of amphiphilic surfactant or protein molecules from the bulk of the solution to the interface. Whey protein and sodium caseinate showed longer induction time approximately 10000 ms compared to the surfactant systems, where induction time was estimated to be approximately 1000 ms. However, in both the protein and surfactant systems, the induction time goes on decreasing with increasing the concentrations. The similar behavior was observed in the mixed system, and lower surface tension values were observed at higher concentrations. The fitting of the experimental data to the theoretical equation shows the presence of two relaxation mechanisms of widely different time scale for the adsorption of surfactant or protein molecules at the interface. The relaxation time strongly varies with the concentrations following the power law, and at fixed concentration it was the highest for whey protein and the lowest for C18:1G5 system. The surface dilatational elasticity determined within the frequency range of approximately 0.1 to 1 cycle/s supports the dynamic surface tension data.