Lipid Changes in Sea Urchin Gonads during Storage

In lipids of salted sea urchin gonads, the changes in contents of neutral lipids (NL), glycolipids (GL) and phospholipids (PL), in peroxide and carbonyl values, in lipid class compositions of NL and PL, and in fatty acid composition were investigated as a function of storage time. NL increased while GL and PL decreased by autolysis during 180 days storage. The increase of NL resulted from free fatty acids (FFA) [plus fatty acid ethyl esters (FAEE)] generated enzymatically by hydrolysis of PL and GL. Triglycerides were stable throughout a period of storage. In heat-treated and salted gonads, NL, GL and PL remained nearly unchanged during storage, and FFA and FAEE could not be detected. The oxidation of lipids was not detected during 180 days storage, although salted gonads had high content of polyunsaturated fatty acids.     

Attitude Control of Quadrotor in Consideration of the Effects of a Pole Based on Limited Pole Placement

This paper introduces an attitude control technique for a quadrotor aircraft. Considering that the nonlinear characteristics of the aircraft makes it difficult to stabilize, a quadrotor controlled with an adaptive algorithm. Accordingly, we proposed a quadrotor application with backstepping based on the Lyapunov function. Furthermore, we designed a separate actuator control to be mounted on the aircraft for the control of the quadrotor. This approach is often used in industrial equipment. In particular, the limited pole placement (LPP) method is applied to design the controller considering the characteristics of the actuator. The representative simulation results are presented and discussed.     

Quantitative analysis and modelling of hepatic iron stores using stereology and spatial statistics

Hepatic iron overload is a common clinical problem resulting from hyperabsorption syndromes and from chronic transfusion therapy. Not only does iron loading vary between reticuloendothelial stores and hepatocytes, but iron is heterogeneously distributed within hepatocytes as well. Since the accessibility of iron particles to chelation may depend, in part, on their distribution, we sought to characterize the shape and scale of iron deposition in humans with transfusional iron overload. Toward this end, we performed a histological analysis of iron stores in liver biopsy specimens of 20 patients (1.3–57.8 mg iron/g dry tissue weight) with aid of electron and light microscopy. We estimated distributions related to variability in siderosomal size, proximity of iron centres and inter‐cellular iron loading. These distributions could be well modelled by Gamma distribution functions over most of the pathologic range of iron concentrations. Thus, for a given liver iron burden, a virtual iron‐overloaded liver could be created that served as a model for the true histologic appearance. Such a model may be helpful for understanding the mechanics of iron loading or in predicting response to iron removal therapy.     

EFFECTS OF CURING ON MORPHOLOGICAL AND THERMAL PROPERTIES OF SALMON-NOSE CARTILAGE AS A VINEGARED DISH IN JAPAN

ABSTRACT Sliced salmon-nose cartilage was cured in 4% acetic acid up to 168h. Using optical microscopy, we observed the reddish-purple color produced by staining with toluisine-blue turned lighter during curing. This meant that the mucopoly-saccharide level of cartilage matrix decreased, causing the structure of the cartilage to become porous. In addition, using scanning electron microscopy, loosenings of collagen fibers was observed after 72 h of curing, thus making the structure of the cartilage fragile. DSC thermograms showed that the denaturation temperature of the native collagen fibers was lowered and an additional peak appeared during curing. These findings lead us to suggest that the collagen in salmon-nose cartilage changes qualitatively during curing.     

Corrosion of Silicon Nitride Ceramics in Aqueous Hydrogen Chloride Solutions

The leaching behavior of pressureless sintered and hotpressed Si₃N₄ containing Y₂O₃, Al₂O₃, and AlN and hot isostatically pressed Si₃N₄ without additives was studied in 0.1 M to 10 M HCl aqueous solutions at 50° to 100°C. Y and Al ions contained in the grain-boundary phase dissolved in HCl solutions, but dissolution of the Si ion from the matrix was negligible. The dissolution of Y and Al ions in HCl solutions was adequately described by a surface-chemical-reaction-controlled, shrinking-core model in <1 M HCl solutions and by a diffusion-controlled, shrinking-core model in >5 M HCl solutions. The rates of dissolution of both Y and Al ions decreased as the degree of crystallinity of the grain-boundary phase increased. The fracture strength of the corroded samples linearly decreased with increasing degree of dissolution of soluble Y and Al ions.     

纳米铁电材料铁电性及其力电耦合特性的原子尺度模拟研究

纳米铁电材料的几何构型和特征尺寸严重影响着材料的铁电性, 对微电子器件中功能材料的可靠性有着至关重要的影响。数值模拟是研究铁电材料物理特性的重要手段, 并且当材料的特征尺寸缩小至数个纳米的量级时, 由于极小试样精密制备和微小物理量准确测量等方面困难的制约, 数值模拟可能是唯一有效的办法。本文综述了典型二维、一维及零维纳米铁电材料铁电性的若干数值模拟研究进展, 重点介绍了纳米铁电材料的极化分布、铁电相变、铁电临界尺寸和力电耦合特性等关键问题的研究成果, 展望了纳米铁电材料模拟研究方面的研究重点。     

Development of a Hybrid Simulator for Power System Analysis for a High Penetration of Distributed Generations

Chubu Electric Power Co., Ltd.’s hybrid power system simulator consists of analog models and hybrid models. The power system facilities are downsized as an analog model, while the synchronous generators and the loads are modeled as an actual current source model through the amplifier and the digital model. In recent years, there is a growing interest in analyzing power system dynamic phenomena caused by a high penetration of distributed generations. Therefore, the multifunctional generator model that can simulate distributed generation has been developed.     

Comparison of two-photon excitation laser scanning microscopy with UV-confocal laser scanning microscopy in three-dimensional calcium imaging using the fluorescence indicator Indo-1

Two-photon excitation laser scanning fluorescence microscopy (2p-LSM) was compared with UV-excitation confocal laser scanning fluorescence microscopy (UV-CLSM) in terms of three-dimensional (3-D) calcium imaging of living cells in culture. Indo-1 was used as a calcium indicator. Since the excitation volume is more limited and excitation wavelengths are longer in 2p-LSM than in UV-CLSM, 2p-LSM exhibited several advantages over UV-CLSM: (1) a lower level of background signal by a factor of 6–17, which enhances the contrast by a factor of 6–21; (2) a lower rate of photobleaching by a factor of 2–4; (3) slightly lower phototoxicity. When 3-D images were repeatedly acquired, the calcium concentration determined by UV-CLSM depended strongly on the number of data acquisitions and the nuclear regions falsely exhibited low calcium concentrations, probably due to an interplay of different levels of photobleaching of Indo-1 and autofluorescence, while the calcium concentration evaluated by 2p-LSM was stable and homogeneous throughout the cytoplasm. The spatial resolution of 2p-LSM was worse by 10% in the focal plane and by 30% along the optical axis due to the longer excitation wavelength. This disadvantage can be overcome by the addition of a confocal pinhole (two-photon excitation confocal laser scanning fluorescence microscopy), which made the resolution similar to that in UV-CLSM. These results indicate that 2p-LSM is preferable for repeated 3-D reconstruction of calcium concentration in living cells. In UV-CLSM, 0.18-mW laser power with a 2.φ pinhole (in normalized optical coordinate) gives better signal-to-noise ratio, contrast and resolution than 0.09-mW laser power with a 4.9-φ pinhole. However, since the damage to cells and the rate of photobleaching is substantially greater under the former condition, it is not suitable for repeated acquisition of 3-D images.     

Large-Area Silicon Sheet Technology Status in United States' Department of Energy Photovoltaics Programs†

Large-area silicon sheet technology is being developed under the U.S. Department of Energy's National Photovoltaics Program to realize high-efficiency, low-cost photovoltaic (PV) cells that are the building blocks of PV modules and arrays.

Both ingot technology and ribbon technology sheet-growth approaches are being pursued. The ingot technology includes Czochralski (Cz) growth and casting processes. Large ingots, both cylindrical and square, have been grown to demonstrate feasibility of producing satisfactory ingots for fabricating PV cells. These developments have been largely adopted by industry and Program-sponsored activities have been reduced. Wafering technology is also being developed, using both rotating-blade and linear-motion saws. Wafering appears to have reached a point where additional fundamental understanding of the sawing mechanism is needed to further wafering technology. Empirical developments have been concluded and only limited fundamental studies, which relate to fracture behavior, continue. Ribbon silicon technologies, such as dendritic-web, edge-defined film-fed growth (EFG) edge-supported pulling growth (ESP), and low-angle silicon sheet (LASS) growth are relatively new in comparison with ingot technologies but have shown steady progress. The ribbon-sheet processes have inherent advantages over the ingot silicon processes. They require minimum silicon material usuage, and they eliminate the wafering step. The cost target for encapsulated cells using both ingot and ribbon processes is $0.70/Wp. Steady progress continues toward this target, and the probability of achieving the cost and technology targets for large-area silicon sheet appears high with at least one of several large-area sheet technologies.     

Long Gap Discharge Guiding Experiments Using Strongly and Weakly Ionized Plasma Channels for Laser Triggered Lightning

A study to generate longer plasma channel was conucted to improve probability of triggered lightning. To generate the long laser plasma channel, a strongly and a weakly ionized plasma channels were used in series, a scheme called hybrid method. The strongly and the weakly ionized plasma channels were used for triggering an electrical leader and guiding the leader. The electrical leader propagated through the weakly ionized plasma. Then main discharge occurred between the electrodes. It is found that the streamer was accelerated with both the increase in the plasma density and the increase in an ambient electric field close to the plane electrode.