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We propose a novel constraint-handling technique for the covariance matrix adaptation evolution strategy (CMA-ES). The proposed technique is aimed at solving explicitly constrained black-box continuous optimization problems, in which the explicit constraint is a constraint whereby the computational time for the constraint violation and its (numerical) gradient are negligible compared to that for the objective function. This method is designed to realize two invariance properties: invariance to the affine transformation of the search space, and invariance to the increasing transformation of the objective and constraint functions. The CMA-ES is designed to possess these properties for handling difficulties that appear in black-box optimization problems, such as non-separability, ill-conditioning, ruggedness, and the different orders of magnitude in the objective. The proposed constraint-handling technique (CHT), known as ARCH, modifies the underlying CMA-ES only in terms of the ranking of the candidate solutions. It employs a repair operator and an adaptive ranking aggregation strategy to compute the ranking. We developed test problems to evaluate the effects of the invariance properties, and performed experiments to empirically verify the invariance of the algorithm. We compared the proposed method with other CHTs on the CEC 2006 constrained optimization benchmark suite to demonstrate its efficacy. Empirical studies reveal that ARCH is able to exploit the explicitness of the constraint functions effectively, sometimes even more efficiently than an existing box-constraint handling technique on box-constrained problems, while exhibiting the invariance properties. Moreover, ARCH overwhelmingly outperforms CHTs by not exploiting the explicit constraints in terms of the number of objective function calls., Accepted to Evolutionary Computation (MIT Press)

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.

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.

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

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

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.

Colloidal dispersions of silver (Ag) particles were prepared by the photoreduction of silver perchlorate (AgClO 4 ) in water/AOT/benzene water-in-oil (w/o) microemulsions consisting of sodium bis(2-ethylhexyl) sulfosuccinate (AOT), water and benzene. Formation mechanisms of Ag particles prepared in the presence of benzoin by photoreduction from Ag + -containing w/o microemulsions were investigated by UV–vis, transmission electron microscopy (TEM), extended X-ray absorption fine structure (EXAFS) and small-angle X-ray scattering (SAXS) measurements. By a combination of TEM and EXAFS results, Ag particles show a metallic nature after the photoreduction and the diameter of Ag particles ranges between 5 and 30 nm. In situ time-resolved SAXS measurements show that the integrated rate equation can be applied in the reduction process of Ag + ions to Ag 0 atoms, and the autocatalytic Ag particle growth proceeds in the association process of Ag 0 atoms during the photoreduction of Ag + -containing w/o microemulsions. The nanometer-sized water droplets microemulsified by AOT in benzene continuous-phase regulated the size of Ag particles, and the size and shape of water droplets were retained during the Ag particle formation.

Photoreduction formation mechanisms of metal particles (gold (Au) and platinum (Pt) particles) in aqueous surfactant solutions of dodecyltrimethylammonium chloride (DTAC) and polyethylene glycol lauryl ether (PEG) have been studied by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and extended X-ray absorption fine structure (EXAFS) measurements. EXAFS results confirmed the metallic nature of the nanoparticles, and showed that the average particle size significantly depends neither on the metal species nor on the charged properties (cationic, anionic, or nonionic) of surfactants. The SAXS analysis indicated that the structure of DTAC and PEG micelles could be fitted with the hard-sphere model having the interaction radius RHS and the spherically shaped core–shell structure. At the beginning of the photoirradiation, the increase of the SAXS intensity at q

Photoreduction formation mechanisms of metal particles (gold (Au) and platinum (Pt) particles) in aqueous solution of sodium dodecyl sulfate (SDS) have been investigated using transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and extended X-ray absorption fine structure (EXAFS) measurements. The anionic surfactant SDS was used as a stabilized reagent to disperse metal particles in aqueous solutions. The average particle diameter of Au and Pt particles was estimated from TEM as 4.5 and 2.7 nm, respectively. The SAXS analysis showed that in high concentration of SDS the size of Au and Pt particles is consistent with those obtained from TEM and EXAFS measurements, and the micelles of SDS retain a core–shell structure in aqueous solutions after the formation of metal particles. In the particle formation process, metal particles were photochemically produced in the core of micelles and they did not significantly affect the morphology of micelles, although these metal ions were almost randomly distributed in solution before the photoreduction. The particle growth rate of Au and Pt could be evaluated on the basis of the weight fraction of these metal particles, and it was found that Au particle growth occurs more rapidly than Pt particle growth in the aqueous SDS solutions.

This paper proposes a piercing based grasping by using the self-tightening effect of objects with elasticity. We suppose a piercing hand with palm where the piercing motion by needle can be independently achieved irrespective of the palm motion. The palm first approaches and touches with the object, with a slight pushing motion. This motion produces an increase of potential energy of object. After the motion, needles pierce the object. When the object is lifted up, the accumulated potential energy is released and the object tries to recover the original shape under the piercing condition. We found a particular mechanical configuration between the object and the needle arrangement, under which the constraint of object is tightened due to the object deformation during the release of potential energy. In order to confirm the robustness of the proposed method, we have done a couple of experiments. The results show that the proposed method keeps an extremely high robustness compared with the other piercing methods.

This paper discusses a design approach on robotic hand by considering the characteristics of visco-elasticity. “NORIMAKI” is a typical example where it has the visco-elastic characteristics. We first show that the dynamic characteristics of “NORIMAKI” can be expressed by utilizing the Maxwell model with two layers. Based on dynamic parameters obtained by experiments, we make clear the relationship among the total working time, the plastic deformation of food after the operation, the hand stiffness, and the operating velocity of the hand. We newly found an interesting behavior where there exists an optimum set of the design parameters for achieving the minimum plastic deformation.

固体高分子形燃料電池に広く用いられているpolyperfluorosulfonic acid (PFSA) 膜について, 湿度を変化させながら赤外 (IR) および小角X線散乱 (SAXS) 測定を行い, 含水状態およびクラスターサイズの変化がイオン伝導度に与える影響を調べた. その結果, 膜中の自由水は束縛水よりもイオン伝導度に対する寄与が大きく, 束縛水と自由水の存在比は膜が置かれた環境の相対湿度に依存して変化した. 30%RH以下では膜中の水はすべて束縛水であり, 60%RH以上で自由水が飛躍的に増加した. 湿度の増加とともにクラスターサイズは徐々に大きくなるが, 60%RHを境に高次構造変化がおき, それまで独立していたクラスターがネットワーク状の太いイオンチャンネルを形成すると考えられた. このような高次構造の変化や自由水の飛躍的な増加により, イオン伝導度が大きくなると考えられた.

For a needle-plane electrode system with a barrier, which establishes the electric field across the axis of a groove, creeping discharge characteristics in N2 gas under µs pulse voltage applications have been investigated. The distance h between the barrier surface and the needle tip as well as the distance M between the groove center and the needle tip were changed. In the case of h=0.3mm, when the needle tip is located near the far-side groove edge from the plane electrode (M=0.6mm), the flashover voltage has the maximum value. At that time, a growth of a corona is suppressed near the groove edge. These unique characteristics should associate with a field relaxation.

This paper describes the discharge characteristics of a needle/dielectric composite electrode in N2 gas produced by a rectangular pulse voltage. Glass or ZnO was placed in contact with the needle for the needle–plane electrode configuration. In the case of glass in contact with the needle, the discharge voltage increased with increasing L (the distance from the tip of the needle to the dielectric). In the case of ZnO in contact with the needle, the discharge voltage increased with increasing L from 0 mm to 2 mm, but it gradually decreased with increasing L from 2 mm to 10 mm. It is considered that these differences in the discharge voltage characteristics originate from the corona extension process and discharge path. © 2001 Scripta Technica, Electr Eng Jpn, 137(1): 1–8, 2001

This paper proposes the consistent method with general equilibrium models to measure use value and non-use value of large-scale change in environmental quality. First, we develop a general equilibrium model that parameters of the utility function with environmental quality as a dependent variable can be estimated on the basis of the travel cost method and the contingent variation method. Second, we examine to identify the general equilibrium impact of environmental quality by a comparative static analysis. Third, considering change in prices and income, we decompose the benefits from change in environmental quality into use value and non-use value. JEL Classifications: C68, Q51, Q54 Keywords: Computable general equilibrium models;Use value; Non-use value

Since plasma facing components such as the first wall and the divertor for the next step fusion reactors are exposed to high heat loads and high energy neutron flux generated by the plasma, it is urgent to develop plasma facing components which can resist these. We have established electron beam heat facility (‘OHBIS’, Oarai hot-cell electron beam irradiating system) at a hot cell in JMTR (Japan materials testing reactor) hot laboratory in order to estimate thermal shock resistivity of plasma facing materials and heat removal capabilities of divertor elements under steady state heating. In this facility, irradiated plasma facing materials (beryllium, carbon based materials and so on) and divertor elements can be treated. This facility consists of an electron beam unit with the maximum beam power of 50 kW and the vacuum vessel. The acceleration voltage and the maximum beam current are 30 kV (constant) and 1.7 A, respectively. The loading time of the electron beam is more than 0.1 ms. The shape of vacuum vessel is cylindrical, and the main dimensions are 500 mm in inside diameter, 1000 mm in height. The ultimate vacuum of this vessel is 1 × 10−4 Pa. At present, the facility for the thermal shock test has been established in a hot cell. The performance of the electron beam is being evaluated at this time. In the future, the equipment for conducting static heat loadings will be incorporated into the facility.

Numerous attempts have been made to evaluate economic impacts by climate change, and the evaluation method can be classified into two approaches. One is a partial equilibrium approach and the other is a general equilibrium approach. The former method includes a travel cost method (TCM) and a contingent valuation method. These methods have applied in some studies to quantify economic value of environmental quality. The partial equilibrium approaches for each case, however, cannot capture economic impacts of changes in natural environment by climate change and environmental conservation policies. On the other hand, the latter method has a computable general equilibrium (CGE) analysis. As a CGE model treats all markets in the economy, both direct and indirect impacts of climate change through changes in the behavior of economic agents can be captured. A CGE model, however, needs the formulation of impacts on environmental quality and the estimation of their parameters in this model. As mentioned above, considerable studies on economic evaluation of climate change have separately analyzed by two approaches. Therefore, by explicit linkage between a partial equilibrium approach and a general equilibrium approach, comprehensive assessments in a general equilibrium framework are needed. To measure economic impacts of the changes in environmental quality by climate change, this study develops a theoretical framework of a CGE model that integrates the utility function that has environmental quality as the independent variable derived from a recreation demand function in a TCM, and confirms the validity of our CGE model through some numerical experiments using the beach erosion scenarios. The findings in this study are shown below. 1) By solving the integrability problem, we derived the utility function that has composite goods, visit frequency to recreation sites and environmental quality in the site as the independent variable from the estimation of a recreation demand function in a TCM, and developed the theoretical framework of a CGE model consistent with the utility function derived in this study. 2) Through some numerical experiments by the beach erosion scenarios, we revealed that our CGE model can evaluate the changes in price and income that are not taken into account in the definition of the consumer surplus derived from the partial equilibrium approach. 3) By testing the economic validity of numerically experimental results, we demonstrated that our CGE model is applicable for empirical analysis of climate change.

In a liquid–liquid interface bioreactor, fungal cells locate in a hydrophilic polyacrylonitrile microsphere layer on an aqueous–organic interface. In this article, effects of hydrophobicity of the interface on n-decane hydroxylation activity of Monilliera sp. NAP 00702 was examined. (−)-4-Decanol production was significantly enhanced to 132% by addition of polytetrafluoroethylene.

The addition of anion-exchange resin microparticles into a polyacrylonitrile (PAN) ballooned microsphere layer drastically enhanced the fermentative activity of Trichoderma atroviride AG2755-5NM398 in an extractive liquid-surface immobilization (Ext-LSI) system. The production of 6-pentyl-α-pyrone (6PP), a fungicidal secondary metabolite, was 1.92-fold higher than the control (PAN alone).

Peptide amphiphile molecules (PA) are remarkably versatile and useful as building blocks for construction of complex supramolecular structures in a bottom-up fashion. Worm-like micelles of PA have been demonstrated to have successful application to creation of synthetic extracellular matrix materials for tissue engineering and regenerative medicine. However, the pathway of the self-assembly process of the PA worm-like micelle has not been fully characterized or understood. This work analyzes the self-assembly process leading to worm-like micelle formation in our designed PA with small-angle neutron scattering and atomic force microscopy. The experimental results demonstrate the existence of transient spherical micelles in the early stage of the process and subsequent micelle chain elongation by attachment of spherical micelles to the end of growing cylindrical micelles to form worm-like micelles in a process mimicking chain-growth polymerization.

The formaldehyde-fixing enzymes, 3-Hexulose-6-phosphate synthase (HPS) and 6-phospho-3-hexuloisomerase (PHI), are the key enzymes catalyzing sequential reactions in the ribulose monophosphate (RuMP) pathway. In this study, we generated two fused gene constructs of the hps and phi genes (i.e., hps-phi and phi-hps) from a methylotrophic bacterium Mycobacterium gastri MB19. The gene product of hps-phi exhibited both HPS and PHI activities at room temperature and catalyzed the sequential reactions more efficiently than a simple mixture of the individual enzymes. The gene product of phi-hps failed to display any enzyme activity. Escherichia coli strains harboring the hps-phi gene consumed formaldehyde more efficiently and exhibited better growth in a formaldehyde-containing medium than the host strain. Our results demonstrate that the engineered fusion gene has the possibility to be used to establish a formaldehyde-resistance detoxification system in various organisms.

Low-lying octupole states of doubly-even 78–86Kr isotopes have been studied with inelastic scattering of 51.9 MeV protons. It is shown that in the doubly-even nuclei from Ge to Sr with N = 42–50, the lowest octupole vibrational energies of nuclei with equal neutron excess are almost the same. The transition strengths of these states increase with Z.

The level schemes of the even 74–82 Se up to E x = 5.0 MeV have been investigated with high-resolution inelastic proton scattering at E p = 64.8 MeV. Several 4 + states with comparable strengths were found at E X = 2.0–5.0 MeV in all isotopes studied. The energy weighted sum-rule fraction of the 4 + states in this region increases with decreasing neutron number from 82 Se (1.0%) up to 76 Se (3.7%), and then decreases in 74 Se (2.6%). A RPA calculation with a pairing plus hexa-decapole-hexadecapole interaction can well reproduce the distribution of the excitation energies and transition strengths for the hexadecapole states.

Two low-lying octupole states of 78,80,82Kr, which were previously observed in inelastic proton scattering to share the low-lying octupole vibrational strength, were found to be strongly excited in the (p,t) reaction. Characteristics of these states and a comparison with the IBM model strongly suggest that the splittings in the lighter isotopes 76,78,80,82Kr are due to a coupling of the octupole vibration to the quadrupole degree of freedom.

The 2+2 and 4+1 states of the even isotopes 78–86Kr have been studied by the inelastic scattering of protons. The B(E2;0+g → 2+2) values of these isotopes are roughly equal, where as the B(E4;+g → 4+1) values decrease to a minimum at 82Kr and then increase with neutron number. Comparison of the experimental results with current theoretical models implies an abrupt change of structure between 78–82Kr and 84–86Kr.

A hyaluronidase activity was demonstrated in rabbit gingiva by determining its ability to release reactive N-acetylhexosamine group from hyaluronate. The optimum pH of the enzyme was 3.6. The enzyme was inhibited by ferric ion, iodoacetamide, and ferrous ion in the decreasing order. The enzyme was activated by protamine and poly-L-lysine. For determining the extent of polymerization of the reaction products, molar ratios of hexosamine to uronic acid were estimated before and after reduction with sodium borohydride. Comparing these vales with those calculated theoretically, it was concluded that the end product of the enzyme reaction was terasaccharide. These results clearly demonstrate that hyaluronidase exists in gingival tissue.