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Broaching-to, an uncontrollable maneuvering problem that may occur in following and quartering seas, can induce large roll motion and sometimes capsizing due to violent yaw motions, e.g., Nicholson (Some Parametric Model Experiment to Investigate Broaching-to, pp 160–166, 1974). Broaching-to arises when a ship cannot maintain its desired course even under maximum steering effort. Previous experiments and numerical simulations of the broaching-to phenomenon have applied proportional-derivative (PD) control, which cannot provide the maximum steering effort. To maximize the steering effort, the previous study replaced PD control by optimal control theory by Maki et al. (J Jpn Soc Nav Archit Ocean Eng 7:207–212, 2008) and Maki et al. (J Jpn Soc Nav Archit Ocean Eng 8:115–122, 2008). A case of the ship control, when the ship developed large yaw motions despite the optimal control, was observed. However, because optimization techniques such as the variational method were insufficiently powerful for solving this highly nonlinear problem, the optimization could be performed only around local optima. The aim is to globally seek a better local solution among the numerous local optima. To achieve this goal, the authors applied the Covariance Matrix Adaption Evolution Strategy (CMA-ES), a state-of-the-art algorithm in evolutionary computation for derivative-free continuous optimization. The optimal rudder control for preventing broaching-to is then obtained, and its characteristics are discussed.

The combination of certain human leukocyte antigen (HLA) polymorphisms with administration of certain drugs shows a strong correlation with developing drug hypersensitivity. Examples of typical combinations are HLA-B*57:01 with abacavir and HLA-B*15:02 with carbamazepine. However, despite belonging to the same serotype, HLA-B*57:03 and HLA-B*15:01 are not associated with drug hypersensitivity. Recent studies have shown that several HLA polymorphisms are associated with multiple drugs rather than a single drug, all resulting in drug hypersensitivity. In this study, we compared the molecular structures and intracellular localization of HLA-B*57:01, HLA-B*58:01, and HLA-B*15:02, which pose risks for developing drug hypersensitivity, as well as HLA-B*57:03 and HLA-B*15:01 that do not present such risks. We found that HLA molecules posing risks have a low affinity for the subunit β

Medaka, Oryzias latipes is distributed in fresh water of South Asia. To study roles of TRPV4 in osmosensing and adaption mechanism of medaka during changes in salinity environment, we isolated the cDNA for TRPV4 from medaka (olTRPV4) and characterized it. The electrophysiological analysis using Xenopus oocytes revealed that olTRPV4 can be activated by a TRPV4-specific agonist, GSK1016790A and acid at pH 5. Further, olTRPV4 was sensitive to 2-APB. Although warm temperatures activate mammalian TRPV4, olTRPV4 was activated by cold and hot stimulation. The threshold for cold activation was determined as 13.13 ± 0.60 °C, and the heat-activation threshold was 40.26 ± 0.25 °C. Further, when olTRPV4-expressing oocytes were stimulated by hypotonic solution, an apparent activation was observed. We further found that the expression of this hypotonic sensor, olTRPV4 was significantly down-regulated in gills but up-regulated in brains of sea water-acclimated medaka. Results demonstrated that olTRPV4 must function as an osmosensor and play important roles in adaption mechanism of medaka fish in various salinity environments.

The air-water interface, which is the boundary of two phases with a large difference in polarity, gives a distinct environment compared with bulk water or air. Since the interface provides a field for various biomolecules to work, it is important to understand the molecular behaviors at the interface. Here, polarity-independent flapping viscosity probes (FLAP) equipped with hydrophobic/hydrophilic substituents have been synthesized and studied at the air-water interface. In situ fluorescence (FL), which is related to the internal motion and orientation, of three different FLAPs were investigated at the interface, and the internal motion of the molecule was indicated to be suppressed at the interface. In addition, the molecular response was compared with that of conventional viscosity probes (molecular rotors), which indicates the different behaviors of FLAP probably due to the distinct molecular orientation as well as molecular motion.

Humans use their tactile sensation to perceive hardness and roughness of an object they touch. Hardness and roughness feeling are related to the contact area and the pressure distribution of the contact surface. Also it is known that the perceived force of a grasped object changes depending on the curvature of the contact surface. The surface texture will affect not only the hardness and roughness feeling but also force perception. In this study, we investigated the effect of a texture with different surface shape on the force perception and hardness feeling of an object. This paper conducted an experiment to reproduce the force felt when an acrylic plate with different surface textures was pressed, and the sensation of hardness and roughness felt during the experiment was evaluated by questionnaire. The texture has a pyramidal shape with aligned projections. In the experiments, we used three different textures with projections of 0.08, 0.2, and 0.5 mm in height, and applied reference forces of 1.1, 2.7, 3.3, 5.0, and 7.8 N. As a result of the experiment with 14 healthy young adults, a statistically significant difference in the exerted force was observed depending on the height of the texture when the reference force was 3.3 N. It was also found that the height had an effect on the roughness but not on the hardness.

The role of a shrinkage reducing agent (SRA) in the hardened cement paste during a first desorption process was investigated by measuring the small-angle X-ray scattering (SAXS). Fractal disc analysis and Guinier approximation were adopted to interpret the SAXS profiles. We experimentally confirmed that the presence of SRA molecules mitigated the piling of calcium-silicate hydrate (C-S-H) sheets, which could be monitored by the increase in the thickness of the disc, representing the agglomeration of C-S-H sheets. In addition, the basal spacing of C-S-H did not change during the drying. By contrast, the diameter of the discs monotonically decreased and showed a similar trend to that of samples lacking SRA. Based on these findings, we concluded that SRA molecules were on the surface of the C-S-H sheets and mitigated the piling, facilitating water removal from the C-S-H agglomeration in the RH range of 80–40%.

Tritium release into the primary coolant of the JMTR and the JRR-3 M had been studied, and it is found that tritium recoil release from the chain reaction of beryllium neutron reflectors is dominant. To prevent the tritium recoil release, Al, Ti, V, Ni and Zr are selected as the candidate tritium recoil barrier materials in this feasibility study. It is clear that 20∼40 μm thickness is required depending on the material to reduce by 3 orders, and that an impact on the effective multiplication factor is about 0.2 % at most. Total evaluation including the activities, fabrication and usage experiences, suggests the selection of Al as the first candidate may have the least development risk as the tritium recoil barrier.

Thermoplastic elastomers are elastomeric materials which contain hard domains as physical cross-linking for rubbery chains. Therefore, the hard domains are required permanently rigid. Nevertheless, we have found experimentally deformation of the hard domains upon uniaxial stretching of the thermoplastic elastomer films. In this paper, we report experimental results of deformation of glassy spherical microdomains in elastomeric triblock copolymer films upon uniaxial stretching, as revealed by two-dimensional small-angle X-ray scattering (2d-SAXS) measurements. Actually, shifts of the peak position of the particle scattering toward lower and higher q-regions were detected for q directions parallel and perpendicular to the stretching direction (SD), respectively, where q stands for the scattering vector. By assuming that spheres simply deformed into prolate spheroids with its major axis parallel to SD, 1d-SAXS profiles measured at several strains were successfully reproduced with model calculation of the 1d-...

Meso- and micro-scale structural changes in matured hardened cement paste dried slowly for 1.5 years at different relative humidities (RHs) are evaluated by small-angle X-ray scattering profiles covering a q range of 0.017 nm − 1 –30 nm − 1 with a fractal disc-shaped particle analysis and Guinier approximation. The fractal disc-shaped particle analysis revealed that calcium–silicate–hydrate (C–S–H) agglomerations are very thin (~ 2.5 nm) and of relatively large width (~ 35 nm) under high RH conditions. However, the agglomerations are segmented (in width) into ~ 10 nm below an RH of 40%. The Guinier approximation found the possibility that the scattering profiles in the range of 2 nm − 1 –8 nm − 1 correspond to a spacing between C–S–H monolayers and it showed stepwise changes at 40%–50% RH. The stepwise behavior of the distance between C–S–H monolayers may explain a kink in water vapor desorption at around 40% RH.

Time saving for emergency patient like as a case of heat stroke is eagerly anticipated especially in recent society of Japan. Though implementation new arterial high-standard road may make a considerable contribution, however in practical management, the way to evaluate in monetary terms such effects those related deeply with human life and health has not been established yet. One possible answer is to put the value of statistical one's life (VSL) into the benefit items, and in nowadays 226 million JPY is recommended by Cabinet Office in Japan nevertheless it has not been justified sufficiently. Therefore in this study, firstly we developed a theoretical model in which one tries to give an account of relationship between the research participants’ age and their WTP for the suggested hypothetical service that has an effect of mortality risk reduction, namely “option”. Actually, WTP is option price itself in this context and perfectly proportional with VSL. Secondly, several types of WTP and VSL are proposed for each generation of the participant. These empirical outcomes show rather consistent with the propositions in theoretical conjecture. Either of WTP of 20s or 30s is the lowest value among generations, in contrast, WTP of over 60 is the firstly or secondly largest value among them nevertheless they might have been retired already and income effect worked not so much. The elderly people seem to be willing to pay more than younger ages to build more safety society. In both viewpoints of theoretical and empirical analysis, WTP and VSL evidently differ among age groups and income groups. We confidently conclude that as the degree of VSL depends heavily on the subject regional circumstances, e.g. economic level, population structure, and so on, sufficient and elaborate preliminary investigation is minimum requirements to road project evaluation.

A field effect transistor (FET) biosensor is a promising device for various applications such as medical diagnosis and environmental monitoring. Because characteristics of FET biosensors are directly influenced by the change of gate-insulator surface potential induced by the adsorption of charged molecules, FET biosensors could provide the rapid and label-free biomolecular detection. Recently, mental stress-related diseases, such as integration disorder syndrome and depression, affect people's health, resulting that simple stress monitoring is expected for early stage detection of the disease. Previously, the relation between concentration of stress markers and mental stress has been reported [1], and the monitoring of circadian concentration of the markers is found to be important for prediction of the stress condition. Especially, secretory immunoglobulin A (s-IgA), which is an immunity-related molecule present in the human mucus, is one of the candidates to be monitored as a stress marker. However, conventional methods for measuring concentration of s-IgA are restricted in daily use due to complex protocol, time-consuming and expensive equipment. Nowadays, we have investigated sensitive detection method for various targets by using the FET biosensor [2,3]. To achieve improvement of the sensitivity, small receptors have been applied to increase electrical responses owing to the effective use of a charge-recognition region from FET gate surface, Debye length [4,5]. In this study, we selected a small plant lectin, jacalin (66 kDa), which specifically binds glycan of hinge region of IgA, as a receptor. Additionally, jacalin was inexpensive compared with antibody due to the purification from jackfruits seeds. From these points, jacalin-immobilized FET biosensor was worth to be investigated to realize a simple, sensitive and low-cost stress monitoring device for stress marker. Thus, we investigated the usefulness of the jacalin as a FET receptor. The SiO2 gate insulator of the FET was exposed to O2 plasma (200 W for 1 min) for introduction of hydroxyl groups reacting with triethoxysilane groups of self-assembled monolayer (SAM). Then, the FET chip was immersed in toluene solvent including 1%(v/w) 3-aminopropyltriethoxysilane in an argon atmosphere (60ºC for 7 min.). Following by the cross-linking by glutaraldehyde, jacalin was immobilized on FET gate surfaces. Finally, ethanolamine capping was performed to prevent the non-specific adsorption of contaminating molecules in analyzed samples, resulting in the fabrication of the jacalin-immobilized FET biosensor. The FET characteristics were measured by sweeping the gate-voltage (V g) from -2.0 V to 0 V with 0.1 V drain voltage (V d) in 0.01 × phosphate buffered saline (pH 7.4). Then, the electrical responses (ΔV g) were analyzed from the FET characteristics before and after the addition of analyte to gate surface. To evaluate the specificity of jacalin-immobilized FET biosensor, ΔV g caused by the addition of s-IgA and human serum albumin (HSA) were measured. The FET charactristics was shifted in a positive direction (+53 mV) due to the adsorption of negative-charged s-IgA (Figure 1a), while the responses related with HSA addition were scarcely observed. Thus, specific capture of the s-IgA molecules by the jacalin-immobilized surface was indicated. Moreover, to evaluate the advantage of jacalin, we compared ΔV g with FET functionalized by antigen binding fragment (Fab), which was obtained by cleaving the anti-s-IgA antibody. An electrical response of Fab-immobilized FET was +24 mV (Figure 1b). The change in ΔV g values for these two FET sensors using jacalin or Fab could be discussed as follows. Jacalin could capture more s-IgA molecules within Debye length from the gate surface of FET. In addition, the jacalin-immobilized FET responded linearly to s-IgA in a concentration range from 0.1 μg/mL to 100 μg/mL. Finally, sweat samples collected from healthy persons were examined with the developed jacalin-immobilized FET biosensor, and clear responses were obtained. From these results, jacalin was found to be useful as a receptor for FET biosensors to achieve a sensitive, simple and non-invasive detection of s-IgA. [1] K. Obayashi, Clin. Chim. Acta, 425, 196-201 (2013). [2] S. Hideshima, M. Kobayashi, T. Wada, S. Kuroiwa, T. Nakanishi, N. Sawamura, T. Asahi, T. Osaka, Chem. Commun., 50, 3476-3479 (2014). [3] S. Hideshima, K. Fujita, Y. Harada, M. Tsuna, Y. Seto, S. Sekiguchi, S. Kuroiwa, T. Nakanishi, T. Osaka, Sens. Bio-Sens. Res., 7, 90–94 (2016). [4] S. Cheng, K. Hotani, S. Hideshima, S. Kuroiwa, T. Nakanishi, M. Hashimoto, Y. Mori, T. Osaka, Materials, 7, (4), 2490-2500 (2014). [5] S. Hideshima, H. Hayashi, H. Hinou, S. Nambuya, S. Kuroiwa, T. Nakanishi, T. Momma, S.-I. Nishimura, Y. Sakoda, T. Osaka, Sci. Rep., 9, 11616 (2019). Figure 1 V g-I d characteristics of (a) jacalin or (b) Fab-immobilized FET biosensor before and after the addition of 100 μg/mL s-IgA. Figure 1

Secretory immunoglobulin A (s-IgA), found in biological fluids, is useful for monitoring condition on mental health to prevent depression. In this study, the non-invasive detection of s-IgA in human sweat was demonstrated using field effect transistor (FET) biosensors modified with a plant lectin, jacalin, as a receptor. The s-IgA molecules were detected with greater sensitivity using the jacalin-immobilized FET biosensors as compared to the sensitivity shown by Fab-immobilized FET biosensors. Jacalin, which is a small lectin tetramer, has four glycan-binding sites and can capture a large number of s-IgA molecules within the charge-detectable region in terms of Debye length. Moreover, the jacalin-immobilized FET biosensor could detect s-IgA at concentrations ranging from 0.1 μg/mL to 100 μg/mL. Additionally, by using a filtration process to eliminate the interference of other components found in human sweat, our FET sensing system could specifically and quantitatively detect s-IgA. Therefore, our results show the utility of this device in monitoring mental stress.

The toughness mechanism of the liquid crystalline epoxy resin DGE(C2-MS-C2))—which has an α-methylstilbene moiety as a mesogenic group and ethylene oxy units as spacers—cured with diaminodiphenylethane (DDEt) was investigated using time-resolved wide-angle X-ray diffraction (WAXD) measurements performed during tensile tests. The WAXD patterns of the isotropic (ISO) and LC networks of DGE(C2-MS-C2)/DDEt indicated the molecular chains in the networks were oriented along the elongation direction, with the LC network being more highly orientated than the ISO network. The dissipation energy generated during the reorientation of the network chains was proposed as the origin of the high fracture toughness of DGE(C2-MS-C2)/DDEt.

Intramolecular rotation of molecules contained in a two-dimensional monolayer or a three-dimensional collapsed film at an air–water interface was investigated by in situ fluorescence spectroscopy of twisted intramolecular charge transfer (TICT) type 9-(2-carboxy-2-cyanovinyl)julolidine (CCVJ) derivatives. The TICT type molecules, CCVJ-C12 and CCVJ-Chol, that contain a linear alkyl dodecyl chain or a cholesteryl group, respectively, as their hydrophobic group, were designed and synthesized to manipulate them at the air–water interface. These lipophilized molecular rotors showed the general properties of TICT molecules in solutions that the fluorescence intensity increases with increasing viscosity of the solvent, which is induced by inhibition of internal molecular rotations. The molecular rotors CCVJ-C12 and CCVJ-Chol formed monolayers at the air–water interface and in situ fluorescence spectroscopy was performed during the in-plane compression of the monolayers. It was revealed that the monomer emissions were suppressed and only after the collapse of monolayers, excimer emission from both layers consisting of CCVJ-C12 or CCVJ-Chol was observed. Suppressed monomer emission from monolayers suggests that intramolecular rotation is not inhibited in dense ordered monolayers. Furthermore, fluorescence spectroscopy of Langmuir–Blodgett (LB) films indicated that molecular rotations are not inhibited in the monolayer transferred on the solid substrates.

Recently, mental stress-related diseases, such as integration disorder syndrome and depression, affect people's health. Previously, the relation between concentration of stress-markers and mental stress condition has been reported, suggesting that a simple and daily detection of these markers from biological samples is important to prevent the disease. Secretory immunoglobulin A (s-IgA) which is present in the non-invasive biological samples, such as sweat or saliva, is one of the candidates to measure the mental stress. For the detection of s-IgA, field effect transistor (FET) biosensor is a promising device to easily and quickly detect biomolecules, as the FET characteristics can be responded to the change of surface potential caused by the adsorption of charged molecules. To achieve a sensitive detection by using FET biosensors, small receptors have been applied for an effective use of charge-recognition region, Debye length [1]. In this study, jacalin, a small tetrameric lectin from plant (66 kDa), was selected as a receptor to detect s-IgA. Each monomer of jacalin has a glycan-binding site to the hinge region of IgA, thus the sensitivity expected to be improved due to increasing the amounts of specifically adsorbed s-IgA. The SiO2 gate surface was exposed to O2 plasma (200 W for 1 min) in order to introduce hydroxyl groups reacting with triethoxysilane groups of self-assembled monolayer (SAM). Then, FET was immersed in 1%(v/w) 3-aminopropyltriethoxysilane toluene solution at 60ºC for 7 min in an argon atmosphere, followed by the cross-linking by glutaraldehyde. After the modification with the cross-linker, jacalin was immobilized on FET gate surfaces, and ethanolamine capping was performed to prevent the non-specific adsorption of contaminating molecules. The electrical responses were calculated by the FET characteristics before and after the addition of target solution. The FET characteristics were measured by sweeping the gate-voltage from -2.0 V to 0 V with 0.1 V drain voltage in 0.01 × phosphate buffered saline (pH 7.4). The immobilization of jacalin through the aminopropylsilane SAM was confirmed from atomic force microscopic images on the surface morphology change of the FET gate surfaces. Additionally, to optimize the immobilization condition, the relationship between concentration of jacalin solution and magnitudes of electrical responses were examined. Then, the specificity of jacalin-immobilized FET biosensor to s-IgA were confirmed by the comparison of responses caused by the addition of s-IgA and human serum albumin (HSA). The ΔV g was shifted in a positive direction due to the negative charges of s-IgA (isoelectric point = 4.5-5.0). On the other hand, when the HSA was added to the FET biosensor, the responses was scarcely observed, suggesting that the jacalin-immobilized surface specifically captured the s-IgA (Figure 1). In addition, a correlation between the FET responses and s-IgA from 100 ng/mL to 100 μg/mL, including the fluctuations of concentration in human sweat sample, was clearly obtained. These results suggested that jacalin could be useful as a receptor for FET biosensors to achieve a simple and sensitive detection of s-IgA. [1] S. Cheng, K. Hotani, S. Hideshima, S. Kuroiwa, T. Nakanishi, M. Hashimoto, Y. Mori and T. Osaka, Materials, 7, (4), 2490-2500, (2014). Figure 1

Fungal cells immobilized with ballooned polyacrylonitrile (PAN) microsphere (MS) on an interface between a liquid medium and a hydrophobic organic solvent efficiently catalyze various microbial transformations such as hydrolysis, reduction, hydroxylation, and epoxidation of lipophilic substrates dissolved in the organic phase (liquid–liquid interface bioreactor; L–L IBR). In this study, the electric charge of MS layer in the L–L IBR was modified by mixing 4 kinds of anion-exchange, 2 kinds of cation-exchange or a chelating resin microparticles, and applied to regio- and stereoselective subterminal hydroxylation of n-decane to (−)-4-decanol by Monilliera sp. NAP 00702. In general, the addition of cation-exchange and chelating resin microparticles into a PAN-MS layer led to the strong inhibition of fungal growth and hydroxylation activity. On the other hand, the addition of anion-exchange resin microparticles having moderate total capacity (≤1.00 meq/g) significantly increased hyphal growth and hydroxylation activity. Especially, the addition of IRA910CT microparticles (total capacity ≥ 1.00 meq/g) into a PAN-MS layer led to 1.6-fold increase of 4-decanol production. Thus, it was concluded that the moderate addition of anion-exchange resin microparticles into an MS layer in the L–L IBR system was effective to enhancement of fungal growth and hydroxylation activity.

We present a mechanistic study of the structural formation on the curing process of the liquid–crystalline epoxy with the simultaneous measurement of SAXS/WAXS using synchrotron radiation. The following behaviors were revealed: after the temperature-jump to the curing temperature, first the system forms the nematic domains; the nematic-to-smectic conversion proceeds after an incubation period; the transformation continues beyond the conversion of 80% of epoxide-amine bond formation and corresponding entire polymer network formation.

Let C be a set of colors, and let ω(c) be an integer cost assigned to a color c in C. An edge-coloring of a graph G is to color all the edges of G so that any two adjacent edges are colored with different colors in C. The cost ω(ƒ) of an edge-coloring ƒ of G is the sum of costs ω(ƒ(e)) of colors ƒ(e) assigned to all edges e in G. An edge-coloring ƒ of G is optimal if ω(ƒ) is minimum among all edge-colorings of G. In this paper, we show that the problem of finding an optimal edge-coloring of a tree T can be simply reduced in polynomial time to the minimum weight perfect matching problem for a new bipartite graph constructed from T. The reduction immediately yields an efficient simple algorithm to find an optimal edge-coloring of T in time O(n1.5Δlog (nNω)), where n is the number of vertices in T, Δ is the maximum degree of T, and Nω is the maximum absolute cost |ω(c)| of colors c in C. We then show that our result can be extended for multitrees.