An extended probabilistic model building genetic network programming using both of good and bad individuals

Classical estimation of distribution algorithms (EDAs) generally use truncation selection to estimate the distribution of the good individuals while ignoring the bad ones. However, various researches in evolutionary algorithms (EAs) have reported that the bad individuals may affect and help solving the problem. This paper proposes a new method to use the bad individuals by studying the substructures rather than the entire individual structures to solve reinforcement learning (RL) problems, which generally factorize their entire solutions to the sequences of state–action pairs. This work was studied in a recent graph‐based EDA named probabilistic model building genetic network programming (PMBGNP), which could solve RL problems successfully, to propose an extended PMBGNP. The effectiveness of this work is verified in an RL problem, namely robot control. Compared to other related work, results show that the proposed method can significantly speed up the evolution efficiency. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Enzymatic Properties of β‐1,3‐Glucanase from Streptomyces sp Mo.

Streptomyces sp Mo endo‐β‐1,3‐glucanase was found to have hydrolyzing activity toward curdlan and released laminarioligosaccharides selectively. The molecular weight was estimated to be 36000 Da and its N‐terminal amino acid sequence was VTPPDISVTN. The optimal pH was 6 and the enzyme was found to be stable from pH 5 to 8. The optimal temperature was 60 °C and the activity was stable below 50 °C. The enzyme hydrolyzed selectively curdlan containing only β‐1,3 linkages. The enzyme had 89% relative activity toward Laminaria digitata laminarin, which contains a small amount of β‐1,6 linkages compared with curdlan, while Eisenia bicyclis laminarin with a higher amount of β‐1,6‐linkages, was not hydrolyzed. Mo enzyme adsorbed completely on curdlan powder. The enzymatic hydrolysis of curdlan powder resulted in the accumulation of laminaribiose (yield 81.7%). Trisaccharide was inevitably released from the hydrolysis of laminarioligosaccharides with 5 to 7 degrees of polymerization (DP). Although the enzyme cleaved off disaccharide (DP 2) from tetrasaccharide (DP 4), the reaction rate was lower than those of DP 5 to 7. The results indicated that the active site of Mo endo‐β‐1,3‐glucanase can efficiently recognize glucosyl residue chain of greater than DP 5 and hydrolyzes the β‐1,3 linkage between the 3rd and 4th glucosyl residue.     

Clarification of strain limits considering the ratcheting fatigue strength of 316FR steel

The effect of ratcheting on fatigue strength was investigated in order to rationalize the strain limit as a design criterion of commercialized fast reactor systems. Ratcheting fatigue tests were conducted at 550 °C. Duration of the ratchet straining was set for a certain number of strain cycles taking the loading condition of fast reactors into account, and the number of cycles for strain accumulation was defined as the ratchet-expired cycle. Fatigue lives decrease as the accumulated strain by ratcheting increases. Mean stress increased during the ratcheting cycle and its maximum value depended on the accumulated strain and the ratchet-expired cycle. Fatigue life reduction was negligible when the maximum mean stress was less than 25 MPa, corresponding to an accumulated strain of 2.2%. Accumulated strain is limited to 2% in the present design guidelines and this strain limit is considered effective to avoid reducing fatigue life by ratcheting. Microcrack growth behaviors were also investigated in these tests in order to discuss the life reduction mechanisms in ratcheting conditions.     

Lubrication performance of multialkylatedcyclopentane oils for sliding friction of steel under vacuum condition

Sliding friction experiments under vacuum lubricated with additive-free multialkylatedcyclopentane (MAC) were carried out using a ball-on-disc tribometer with 440C stainless steel as the material of the specimen. Antiwear characteristics of additive-free MAC during the steady friction region under vacuum were shown to be better than those of perfluoropolyether (PFPE). However, it was found that the friction coefficient lubricated with the additive-free MAC under vacuum showed an initial seizure-like high friction of approximately 0.2 at the beginning of the test, followed by a steady low friction of approximately 0.1. It was also found in contrast that PFPE did not show the initial seizure-like high friction but maintained a lower friction coefficient than 0.1 throughout the experiment. The initial high wear volume lubricated with the additive-free MAC was found to be related to the initial seizure-like high friction. The tricresylphosphate formulation prevented the initial seizure-like high friction. Copyright © 2007 John Wiley & Sons, Ltd.     

Noncontact measurement of deep tissue absorption coefficient using Spatially Resolved Near‐Infrared Spectroscopy

We examined the influence of probe‐tissue distance on the relationship between the deep tissue absorption coefficient and the spatial profile of light intensity by Monte Carlo simulation and in vivo experiments, using noncontact spatially resolved near‐infrared spectroscopy (SRS). These results suggest that noncontact SRS can be reliably used for noncontact measurement of the absorption coefficient and oxygen saturation of deep tissues. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

陶瓷色料中添加发色离子的状态与反应

固体滴定法是研究固溶量的一种新方法。本实验选择Mn-Al2O3色料,给其中加入Cr2O3,通过测定反射光谱f(R)、晶格常数、电子自旋共振（ESR）,并计算晶格常数,分别得到加入Cr2O3前后的Mn-Al2O3的反射光谱与晶格常数的变化,依据该数据来推定着色离子Mn的固溶量及化学状态。为研究Mn-Al2O3红色料中Mn的固溶量,给其中加入Cr2O3,它使Mn-Al2O3红的色调发生变化,在此过程中发生如下反应：Cr^3 Mn^3 →Cr^4 Mn^2 ,Mn-Al2O3红色料在反射光谱520nm处有吸收峰值,给其中添加Cr2O3后峰值减小,用Cr^3 的固溶量（即Cr2O3的添加量）和峰值Δf(R)作图并延伸图线至Δf(R)=0点,此点对应的Cr2O3值即为Mn^3 的固溶量（Mn2O3的浓度）。实验证明,利用固体滴定法在一定精度范围内测定发色元素的固溶量取得一定程度成功。锰红色料中的发色离子状态为Mn^3 ,添加Cr2O3后,Cr能置换Mn-Al2O3中的Mn。铬是以Cr^3 化学状态固溶到Al2O3中的。     

Fabrication of semi-transparent superoleophobic thin film by nanoparticle-based nano–microstructures on see-through fabrics

Superoleophobic thin films have many potential applications including fluid transfer, fluid power systems, stain-resistant and antifouling materials, and microfluidics. Transparency is also desired with superhydrophobicity for numerous applications; however, transparency and oleophobicity are almost incompatible with each other from the point of view of surface structure. Oleophobicity requires a rougher structure on the nano–microscale than hydrophobicity, and this rough structure brings light scattering. So far, there are few reports of compatible transparency and superoleophobicity. In this report, we propose see-through-type fabrics having nanoparticle-based hierarchical structure thin films to improve both oleophobicity and transparency. The vacant space between the fibers of the fabric has two important roles: to allow light to pass through and to induce an air layer to produce a Cassie state of a liquid droplet on the resulting thin film. To realize a low surface energy and nanoscale rough structured surface on fabric fibers, we used a spray method with perfluoroalkyl methacrylic copolymer, silica nanoparticles, and volatile solvent. Scanning electron microscopy images revealed that hierarchical nanoparticle structures were uniformly formed on the fabrics. The transparency of the obtained thin film was approximately 61 %, and the change of transparency between the non-coated and coated fabrics was 11 %. The contact angles of oil (rapeseed oil and hexadecane) and water droplets on the fabricated film were observed to be over 150° during investigation of its surface wettability.     

A three-dimensional microfluidic tumor cell migration assay to screen the effect of anti-migratory drugs and interstitial flow

Most anti-cancer drug screening assays are currently performed in two dimensions, on flat, rigid surfaces. However, there are increasing indications that three-dimensional (3D) platforms provide a more realistic setting to investigate accurate morphology, growth, and sensitivity of tumor cells to chemical factors. Moreover, interstitial flow plays a pivotal role in tumor growth. Here, we present a microfluidic 3D platform to investigate behaviors of tumor cells in flow conditions with anti-migratory compounds. Our results show that interstitial flow and its direction have significant impact on migration and growth of hepatocellular carcinoma cell lines such as HepG2 and HLE. In particular, HepG2/HLE cells tend to migrate against interstitial flow, and their growth increases in interstitial flow conditions regardless of the flow direction. Furthermore, this migratory activity of HepG2 cells is enhanced when they are co-cultured with human umbilical vein endothelial cells. We also found that migration activity of HepG2 cells attenuates under hypoxic conditions. In addition, the effect of Artemisinin, an anti-migratory compound, on HepG2 cells was quantitatively analyzed. The microfluidic 3D platform described here is useful to investigate more accurately the effect of anti-migratory drugs on tumor cells and the critical influence of interstitial flow than 2D culture models.     

Immunoglobulin-secreting cells in primary immunodeficiency diseases

To assess immunoglobulin production in vivo, the numbers of immunoglobulin-secreting cells were measured in uncultured peripheral blood mononuclear cells (PBMCs) of patients with primary immunoglobulin deficiency. The numbers of immunoglobulin-secreting cells were found to be variable, and they were well correlated with the serum concentrations of all three major immunoglobulin classes. Our results suggest that measurement of immunoglobulin-secreting cells in PBMCs is useful in the assessment of the ability to produce immunoglobulin in vivo.