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This paper describes two different types of GaAs-HBT compatible, base-collector diode 0/20-dB step attenuators-diode-linearizer type and harmonics-trap type-for 3.5-GHz-band wireless applications. The two attenuators use an AC-coupled, stacked type diode switch topology featuring high power handling capability with low bias current operation. Compared to a conventional diode switch topology, this topology can improve the capability of more than 6 dB with the same bias current. In addition, successful incorporation of a shunt diode linearizer and second- and third-harmonic traps into the attenuators gives the IM3 distortion improvement of more than 7 dB in the high power ranging from 16 dBm to 18 dBm even in the 20-dB attenuation mode when IM3 distortion levels are basically easy to degrade. Measurement results show that both the attenuators are capable of delivering power handling capability (P 0.2dB ) of more than 18 dBm with IM3 levels of less than -35 dBc at an 18-dBm input power while drawing low bias currents of 3.8 mA and 6.8 mA in the thru and attenuation modes from 0/5-V complementary supplies. Measured insertion losses of the linearizer-type and harmonics-trap type attenuators in the thru mode are as low as 1.4 dB and 2.5 dB, respectively.

In this study, cross-linked materials were prepared using the branched macromonomer with different CL/LA molar ratios, and feasibility studies for tissue engineering were carried out. The thermal and mechanical properties of these materials depended on the CL/LA compositions; however, there was no change in the wettability of each material. The HeLa cells adhesion and growth on the CL-LA7030c were equal to that on the commercially available polystyrene dish. The protein absorption experiment using the FBS proteins revealed that the materials with well-grown cells showed better adhesion of the proteins. [photo: see text]

維持透析を受ける血液透析 (HD) 患者は身体機能が低下しているため, 習慣的な運動を続けることが困難な場合が多い. HD患者の身体機能を維持・向上するためには, HD患者の特徴を考慮した効果的な運動療法の介入方法を構築する必要がある. 本研究は, 維持HD患者の運動継続に影響を及ぼすセルフ・エフィカシー (SE) を評価し, 身体機能とSEとの関係からHD患者に対する運動療法の効果について検討した. 維持HD患者122例を運動群と非運動群に分類して, 運動群には運動療法としてelastic resistance training (ERT) を2か月間施行し4か月間の観察期間を設けた. 6か月の研究期間を終了した運動群24例と非運動群20例を対象に, 患者背景因子としてHD期間, dry weight, body mass index, ヘマトクリット, 血清アルブミン, 症状得点, 身体機能 (PF) 偏差得点を, 身体機能の指標として握力と等尺性膝伸展筋力を測定した. 日常身体活動に対するSEの評価として身体活動SE尺度を用い, 上肢の運動に対するSE (上肢SE), 下肢の運動に対するSE (下肢SE) を算出した. 上肢SEを規定する因子として握力とPF偏差得点 (p

維持血液透析 (HD) 中に生じる血圧低下の原因として, 自律神経障害による血管収縮能の低下が関与することが知られているが, HD中の血圧低下の発生機序を詳細に検討し自律神経障害との関係について言及した報告は極めて少ない. 本研究は, 最大エントロピー法を用いてHD中の心拍変動を解析し, HD患者における透析時低血圧の発生機序について検討した. 日中にHD治療を受けている慢性腎不全患者56例を対象とし, HD中の血圧変化によって2群に分類した. すなわち, HD開始時の収縮期血圧と比較して, HD中の収縮期血圧の低下が30mmHg未満の患者を血圧不変群, 収縮期血圧が30mmHg以上低下した患者を血圧低下群とした. HD中は30分毎に血圧と心拍数を測定し, 患者背景因子として年齢, 性別, BMI, 糖尿病合併の有無, dry weight, 左室駆出率, BNPを調査した. 除水量はHD前後の体重変化をHD後の体重で除した除水率で評価した. 動脈硬化度の指標として, HD開始前に動脈波伝播速度 (PWV) を測定し, 身体活動量は国際標準化身体活動量質問表 (IPAQ) を使用して1週間の消費エネルギーを推定した. 自律神経活動の評価は, HD開始前にHolter24時間心電図を装着し最大エントロピー法にて心電図RR間隔の心拍変動解析を行い, 高周波成分 (HF) を副交感神経活動, 低周波成分 (LF) とHFとの比 (LF/HF) を自律神経活動のバランス, エントロピーを心拍変動の乱雑性の指標とした. 患者背景因子は両群間で有意差を認めず, 血圧低下群は, 血圧不変群と比較してPWVが有意に高値を (p

Thermostable α-glucan phosphorylase-catalyzed enzymatic copolymerization of α-d-glucose 1-phosphate (Glc-1-P) with its analogue monomer, α-d-glucosamine 1-phosphate (GlcN-1-P), from a maltotriose primer was performed to produce non-natural heteroaminopolysaccharides composed of Glc/GlcN units, that is, α(1→4)-linked glucosaminoglucans. The GlcN units in the products were further converted to N-acetyl-d-glucosamine (GlcNAc) units by N-acetylation. The structures of the products were evaluated by the MALDI-TOF MS, (1)H NMR, and (1)H-(1)H COSY NMR measurements, which were completely different from those of the natural glycosaminoglycans. The degrees of polymerization and Glc/GlcN compositional ratios of the products were relatively dependent on the Glc-1-P/Glc-1-P/Glc3 feed ratios. The noncrystalline natures of the present materials were supported by the X-ray diffraction measurement.

Surface-initiated graft atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) from self-assembled chitin nanofibers (CNFs) was performed under dispersion conditions. Self-assembled CNFs were initially prepared by regeneration from a chitin ion gel with 1-allyl-3-methylimidazolium bromide using methanol, the product was then converted into the chitin nanofiber macroinitiator by reaction with α-bromoisobutyryl bromide in a dispersion containing N,N-dimethylformamide. Surface-initiated graft ATRP of MMA from the initiating sites on the CNFs was subsequently carried out under dispersion conditions, followed by filtration to obtain the CNF-graft-polyMMA film. Analysis of the product confirmed the occurrence of the graft ATRP on the surface of the CNFs.

The relationship between two aminopolysaccharide stereoisomers, namely α-(1→4)- and β-(1→4)-linked (N-acetyl)-D-glucosamine polymers, is of significant interest within the field of polysaccharide science, as they correspond to amino analogs of the representative abundant natural polysaccharides, viz. amylose and cellulose. While the latter glucosamine polymer is the basis of well-known natural polysaccharides, chitin and chitosan (linear polysaccharides composed of β-(1→4)-linked N-acetyl-D-glucosamine and D-glucosamine), to the best of our knowledge, the former (α-(1→4)-linked) has not been observed in nature. For the purpose of these studies, the synthesis of such non-natural aminopolysaccharides was performed by the thermostable α-glucan phosphorylase (from Aquifex aeolicus VF5)-catalyzed enzymatic polymerization of α-D-glucosamine 1-phosphate (GlcN-1-P), via successive α-glucosaminylations, in ammonia buffer containing Mg(2+) ions, resulting in the production of the α-(1→4)-linked D-glucosamine polymers, corresponding to the structure of the chitosan stereoisomer. Subsequent N-acetylation of the products gave the aminopolysaccharides, corresponding to the chitin stereoisomer.

Rigorous coupled-wave analysis (RCWA) has been used for determining periodic grating structures of diffractive optical elements (DOE) such as rectangular surface-relief gratings. When we observed a cross-sectional image of a manufactured rectangular grating by the scanning transmission electron spectroscopy (STEM), we found that the rectangular structure was deformed to a trapezoidal shape with non-zero corner radii. Therefore, we assumed that we could derive more accurate diffraction efficiencies by RCWA using parameters of the trapezoid such as the height, base angles, and the corner radii as well as the grating pitch. However, each parameter varies in distribution, resulting in a variation in diffraction efficiencies. Tolerance analysis in the design stage is effective in quantitatively predicting that the diffraction efficiencies are in the allowable ranges. Therefore, we have developed a Monte Carlo simulation program by applying RCWA, which can handle distributions of these trapezoid parameters. The program can also handle the distributions of the thickness and refractive indices of the thin films deposited on the grating. The distributions of the trapezoid parameters were obtained through multiple measurements of the substrates without thin films using atomic force microscopy. The distribution of the thickness and refractive indices of the thin films were obtained from analyzed data measured in the vacuum deposition equipment. According to our measurements of the diffraction efficiencies of the manufactured gratings, the diffraction efficiencies have been in the allowable range, and have also been consistent with the Monte Carlo simulations for the tolerance analysis.

Polymer hybrids designed on a nanometer scale were prepared by several methods with an aluminosilicate nanofiber, “imogolite.” This review paper introduces the preparation of polymer hybrid materials from imogolite nanofiber by two different approaches. In order to realize the fine dispersion of imogolite in polymer matrix, poly(vinyl alcohol)/imogolite hybrids were prepared by in situ synthesis method of imogolite in polymer solution. In addition, through utilizing the strong interaction between phosphoric acid group and Al–OH on the surface of imogolite, poly(methyl methacrylate)/imogolite hybrid, and enzyme/imogolite hybrid gel were prepared and characterized.

In this study, a differential scanning calorimetric analysis was performed to investigate the role of water existing around the polymer chains on their thermoresponsive behaviors using the novel functional temperature-sensitive copolymer, poly(N-isopropylacrylamide-co-2-hydroxyisopropylacrylamide) (poly(NIPAAm-co-HIPAAm)). The HIPAAm comonomers were incorporated into the polymeric chains as hydrophilic parameters, and then the hydration states of poly(NIPAAm-co-HIPAAm) with various HIPAAm compositions were examined. Bound water, which is affected by the polymeric chains to some extent, was produced by adding the copolymers to the water, and the temperature due to the melting of the bound water decreased as the HIPAAm content increased. On the basis of this result, we considered that the interaction between the bound water and the polymeric chains is reinforced by the increasing HIPAAm composition. In addition, the cloud points of the copolymers shifted to a higher temperature, and the endothermic enthalpy for the phase transition decreased with increasing the HIPAAm content, suggesting that the number of water molecules disassociated from the polymeric chains decreased. Based on these results, we postulate that the changes in the interaction between the thermosensitive polymer and bound water exert a strong influence on its phase transition and/or separation, such as the cloud point or dehydration behavior.

In this study, magnetite nanoparticles conjugated with the temperature-responsive N-isopropylacrylamide-based functional copolymer were prepared. Observations using a transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) spectral measurements proved that the surrounding polymer layers bind to the magnetite surfaces. The particles showed a very sensitive temperature-responsive behavior, which was confirmed by particle size analysis and investigation of retention in a hydrophobic octadecylsilane (ODS)-modified column. In the magnetic field that was induced by an alternating electric current, the nanoparticles also demonstrated a sensitive temperature-responsive behavior and this result meant that the temperature-responsive polymer layer could absorb the heat induced in the magnetite cores. The temperature-responsive magnetite nanoparticles could show effective aggregation formation or hydrophobic interaction in response to an alternating magnetic field. These interesting phenomena would be used for embolization therapy or targeted drug delivery aiming at a cancer treatment.

The adsorption of proteins on poly(2-hydroxyethyl methacrylate) (PHEMA) brushes was systematically studied by quartz crystal microbalance (QCM) and fluorescence microscopy as a function of graft density and protein size. The graft density σ (chains/nm2) ranged from 0.007 (dilute or semidilute brush regime) to 0.7 (concentrated brush regime), and the protein size ranged from 2 to 13 nm in an effective diameter. The lowest-density brush (σ = 0.007) adsorbed all the tested four proteins, while the highest-density brush (σ = 0.7) adsorbed none of them. The middle-density brush (σ = 0.06) showed an intermediate behavior, adsorbing the smallest two proteins but effectively repelling the largest two. PHEMA cast films adsorbed a probe protein with the adsorbed amount increasing approximately proportionally to the film thickness, indicating that the adsorption mainly occurred in the bulk of the film. The noted results for the brushes support the idea of size-exclusion effect, an effect characteristic of concentrat...

In the present paper, numerical simulation about press forming process of glass lens using finite element method is investigated. It is well known that constitutive equation (elastic constants) of glass depend on time-history and temperature. Therefore, stress relaxation or creep arise on the glass subjected to applied loading, and these behaviors vary drastically depending on the temperature. In the present study, creep test has been conducted to determine the thermo-viscoelastic properties of glass. The creep function obtained by the experiment has been transformed into relaxation function employing Laplace transform and its inversion. Shift factor which gives the relation between the time and temperature can be determined by creep test under several temterature, too. Using typical glass “TaF-3” which has been used for press forming, some numerical simulation by FEM are demonstrated. Residual stresses and residual deformations under some processing conditions are estimated, and the optimal conditions of forming process for glass lens are discussed in detail.

Novel photo-cross-linkable polymers were synthesized for the preparation of the hydrogels with both pH- and temperature-responsive properties. Photo-reactive 4-aminobenzophenone (BP) was introduced into the side groups of poly(N-isopropyl-acrylamide-co-2-carboxyisopropylacrylamide). This starting copolymer was designed for the highly random sequences of comonomers. The introduction degree of BP was controlled by changing the ratio between the BP and the carboxyl groups. The cylinder-shaped hydrogel was easily prepared by UV irradiation for a few minutes. The photo-cross-linked hydrogels exhibited clear volume phase transitions in response to both pH and temperature changes and expected to be used for drug delivery systems.

The objective of this study is to develop a sensitive temperature-responsive material that would function near body temperature. To achieve this purpose, we compounded 2-branched and 4-branched poly(epsilon-caprolactone) macromonomers to modulate the transition temperatures of the resulting cross-linked materials. The temperature-responsive properties were studied using differential scanning calorimetry and X-ray diffraction measurements. As a result, the mixing ratios of each macromonomer or the total macromonomer concentrations were very dominant in modulating the transition temperatures. The materials could successfully control the permeation of the model drug, prednisolone, near body temperature.

Novel polymer nanohybrid was prepared by free radical polymerization of methyl methacrylate in the presence of inorganic nanofiber ‘imogolite’ as reinforcing nanofiller. Imogolite is a hydrous aluminosilicate with a unique nanofiber structure. The surface of imogolite was modified with 2-acidphosphoxyethyl methacrylate, which has a polymerizable methacrylate group and a phosphoric acid moiety, before preparation of polymer hybrid. The polymer nanohybrid was prepared by free radical polymerization in the presence of surface modified imogolite. The mechanical properties of (PMMA/modified imogolite) hybrid with the modified imogolite were improved in comparison with those of PMMA and (PMMA/unmodified imogolite) blend. Furthermore, the hybrid film prepared from the surface modified imogolite kept the transparency similar to PMMA film. These results indicate the usefulness of the surface modification method with phosphoric acid groups and imogolite nanofibers as a reinforcing material.

This paper describes a 3.5V operation InGaP HBT MMIC power amplifier module for use in GSM/EDGE dual-mode, 900/1800/1900 MHz triple band handset applications. Conventional GSM amplifiers have a high linear gain of 40 dB or more to realize efficiency operation in large gain compression state exceeding at least 5 dB. On the other hand, an EDGE amplifier needs a linear operation to prevent signal distortion. This means that a high linear gain amplifier cannot be applied to the EDGE amplifier, because the high gain leads to the high noise power in the receive band (Rx-noise). In order to solve this problem, we have changed the linear gain of the amplifier between GSM and EDGE mode. In EDGE mode, the stage number of the amplifier changes from three to two. To reduce a high gain, the first stage transistors in the amplifier is bypassed through the diode switches. This newly proposed bypass circuit enables a high gain in GSM mode and a low gain in EDGE, thus allowing the amplifier to operate with high efficiency in both modes while satisfying the Rx-noise specification. In conclusion, with diode switches and a band select switch built on the MMIC, the module delivers a P out of 35.5 dBm and a PAE of about 50% for GSM900, a 33.4 dBm P out and a 45% PAE for GSM1800/1900. While satisfying an error vector magnitude (EVM) of less than 4% and a receive-band noise power of less than -85dBm/100kHz, the module also delivers a 29.5 dBm P out and a PAE of over 25% for EDGE900, a 28.5 dBm P our and a PAE of over 25% for EDGE 1800/1900.

A well-defined, high-density poly(2-hydroxyethyl methacrylate) (PHEMA) brush was fabricated on the surface of a poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) film by surface-initiated living radical polymerization (LRP). First, a sufficient amount of peroxides as initiating moieties were successfully introduced on the film surface without causing etching by the O2-plasma treatment. Subsequently, the polymerization mediated by reversible addition−fragmentation chain transfer (RAFT) was carried out at a mild temperature in a nonsolvent for FEP to minimize the swelling of the FEP film surface and avoid the growth of chains from deep inside of the film. The contact angle and ESCA measurements indicated that the boundary intermixing layer between FEP and PHEMA layers was reasonably thin (≤10 nm), meaning that the PHEMA brush was grown nearly regioselectively from the surface of the FEP film. The graft density was estimated to be about 0.3 chains/nm2, which is almost the same as the one achievable by t...

We summarized the Therapeutic Guidelines for Atopic Dermatitis 2002, and outlined important points with reference to medical care and management of atopic dermatitis.

In this study, we found that thermostable α-glucan phosphorylase from Aquifex aeolicus VF5 catalyzed enzymatic successive α-mannosylations of maltotriose using α-D-mannose 1-phosphate as a glycosyl...

We investigate the temperature-induced mixed valence transition in EuNi 2 (Si 0.20 Ge 0.80 ) 2 using Hard X-ray (5940 eV) photoemission spectroscopy (HX-PES), with a probing depth larger than 5 nm....

Polymer-grafted magnetite (Fe3O4) nanoparticles (diameter about 10 nm) were prepared through a direct polymer grafting reaction from their surfaces. The chemisorbed initiator (TEMPO-based alkoxyamine) for nitroxide-mediated radical polymerization with a phosphoric acid group gave controlled polystyrene (PS) and poly(3-vinylpyridine) (P3VP) graft layers on the surface. The graft densities of polymers on the surfaces of magnetite particles were estimated at 0.12−0.20 chains/nm2 by thermogravimetric analysis (TGA). The improvement in the dispersibility of PS-modified magnetite in good solvents was verified by ultraviolet−visible (UV−vis) absorption spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). In the case of P3VP-modified magnetite, the particles were stably dispersed in good solvents, by protonation, in acid solution, and by quarternization with iodomethane, in neutral aqueous solution. The magnetic response of the polymer-grafted magnetite against an external mag...

Power-to-melts of uranium–plutonium oxide fuel pins at an initial startup condition were experimentally obtained from the B5D-2 test in the experimental fast reactor JOYO in Oarai Engineering Center. MCNP code calculations were combined with burnup measurements to determine linear heat rating of the test fuel pins. To identify the axial incipient melting positions corresponding to the power-to-melts, solidified grain morphology and molten fuel axial movements were characterized. Extensive observations on longitudinal ceramographs allowed classifying molten fuel settlements near bottom and top extents of axial fuel melting into three types. The power-to-melts depended slightly on fuel-to-cladding gap sizes and clearly on both oxygen-to-metal ratios and densities of fuel pellets. These dependencies resulted from the fuel pellet cracking and relocation behavior, which fairly improves heat transfers across the gaps. Also, the power-to-melt at the bottom position was higher than that at the top position due to an axial gradient of cladding temperatures in each fuel pin.

This paper describes a proximity correction for fabricating a chirped diffraction grating by direct-writing electron-beam lithography. The electron dose distribution is optimized by calculation with an electron-scatter simulator and a resist development simulator. These simulators are based on the Monte Carlo method and a cell removal model, respectively. To avoid an excessive increase in calculation time, the calculation was performed with 100 nm×100 nm square cells at an accuracy larger than that desired. Also, the resist profile was estimated accurately by adopting the interpolation with the resultant cell profile. In the case of a chirped period grating of 5 mm in width, it took 24 h to calculate the optimum electron dose profile. Moreover to investigate the validity of this correction method a chirped period grating of 0.1 mm in width was fabricated with the calculated dose profile.

The effects of pressure on the temperature-induced coacervation of copoly(N-vinylformamide–vinylacetate) and copoly(N-vinylacetylamide–vinylacetate) in aqueous solution were investigated by measuring the apparent light scattering, and the effects of the concentrations of polymer and inert salt were also studied. At lower pressures, the apparent temperature of transition, Tc, increased with an increase in the pressure, but further increases in pressure decreased Tc. In contrast, the apparent pressure of transition, Pc, monotonously increased with decreasing fixed temperature. The T–P diagram was elliptical, but the curvature was not large and extrema were not observed in the low-temperature and high-pressure range. Anions with low lyotropic numbers induced an almost linear decrease in the Tc and Pc, whereas anions with a high number increased the Tc and Pc. In both polymers, the Tc and Pc depended on the concentrations of the polymers, reflecting the association/aggregation mechanism of coacervation. This is in contrast to typical thermoresponsive polymers such as poly(N-isopropylacrylamide) and poly(N-vinylisobutyramide), which show the coil-collapse transition as a single molecular event.

The molecular weights of poly(N-vinylformamide) [poly(NVF)] obtained by free-radical polymerization were expanded from being in the range of thousands to hundreds of thousands. Primary amino groups were introduced by the hydrolysis of poly(NVF) under both acidic and basic conditions. After 2 h polyvinylamine [poly(VAm)] was given at 60°C under a 2N NaOH solution. The apparent activation energy of poly(NVF) hydrolysis was 61.8 kJ/mol. Furthermore, alkyl side chains were partly introduced by a polymer modification reaction in poly(VAm) with carboxylic acid, using WSC (water-soluble carbodiimide) as the activating agent to produce the stimuli-responsive poly(VAm) derivative. The effects of external stimuli such as temperature and pH on the phase-transition behavior of the copolymers were then studied. The lower critical solution temperature at pH 12 decreased depending on the alkyl group content. The phase-transition behavior of the resulting polymers was also found to vary depending on the side-chain length of the alkyl groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1277–1283, 2003

Free radical copolymerization of water-soluble N-vinylamides such as N-vinylacetamide (NVA) and N-vinylformamide (NVF) with hydrophobic vinyl acetate (VAc) gave amphiphilic copolymers. The monomer reactivity ratios were determined as r 1 = 5.8 and r 2 = 0.68 (M 1 = NVA, M 2 = VAc) and r 1 = 6.2 and r 2 = 0.37 (M 1 = NVF, M 2 = VAc), respectively. The growing radical of the terminals of N-vinylamides propagates more favorably for N-vinylamide monomers than for VAc monomer, resulting in the possible formation of blocky copolymers. It is found that aqueous solutions of these amphiphilic copymers exhibited a lower critical solution temperature (LCST), depending on their chemical composition, followed by coacervate formation above the LCST. Furthermore, thermosensitive hydrogels could be prepared by the free radical copolymerization of N-vinylamide and VAc in the presence of the crosslinker butylenebis(N-vinylacetamide) (Bis-NVA). The swelling ratios of these hydrogels decreased with an immediate increase in temperature from 20 to 80°C, and then reversibly increased with decreasing temperature. These hydrogels showed the same thermosensitive properties as linear copolymers of NVF and VAc.

This paper describes a single-chip RF transceiver LSI for 2.4-GHz-band Gaussian frequency shift-keying applications, such as Bluetooth. This chip uses a 0.18-/spl mu/m bulk CMOS process for lower current consumption. The LSI consists of almost all the required RF and IF building blocks: a transmit/receive antenna switch, a power amplifier, a low noise amplifier, an image rejection mixer, channel-selection filters, a limiter, a received signal strength indicator, a frequency discriminator, a voltage controlled oscillator, and a phase-locked loop synthesizer. The bandpass filter for channel selection was difficult to achieve since it operates at a low supply voltage. However, because large interference is roughly rejected at the output of the image rejection mixer and a wide-input-range bandpass filter with an optimized input bias is realized, the transceiver can operate at a supply voltage of 1.8 V. In the IF section, we adopted a circuit design using the minimum number of passive elements, resistors and capacitors, for a lower chip area of 10.2 mm/sup 2/.

The thermal conductivity of MOX fuel containing FP precipitates such as oxide and metallic inclusions was evaluated by using a finite element method. (U0.8Pu0.2)O2 and (M0.94Nd0.06)O2 (M: U0.8Pu0.2) were employed as the fuel matrix, and BaUO3 and Mo-Ru-Rh-Pd alloy as the inclusions. The dispersed phase size and concentration were determined from post irradiation examination results of about 10 at.% burnup MOX fuel. 2.5 vol.% of the spherical inclusions with the diameter of 25 μm were dispersed in the fuel matrix cube with a size of 400×400×400 μm. The effect of the inclusions on the thermal conductivity of the fuel pellet was calculated to be at most several percents, which is about one order lower than that of the dissolved FPs.

The phase equilibria in the pseudo-ternary BaUO3-BaZrO3-BaMoO3 system were studied to understand the thermochemical properties of the perovskite type gray oxide phase in high burnup MOX fuel. Thermodynamic equilibrium calculation for the system was performed by using a ChemSage program under the various oxygen potentials. Solid solutions existing in the system were treated by an ideal solution model. The present calculation results well agreed with the previous reported post irradiation examination results, showing that BaMoO3 was scarcely included in the gray oxide phase.

A temperature-responsive synthetic vinyl polymer with hydrogen-bonding and hydrophobic side residues, poly(N-vinylisobutyramide) (PNVIBA), was studied for its calorimetric properties in aqueous solutions. The temperature-responsive behavior was dependent on the polymer concentration at lower range and also on the concentration of added sodium dodecyl sulfate (SDS) at higher range. Thermodynamic parameters and molecular weight dependence were discussed in comparison with the corresponding results from poly(N-isopropylacrylamide) (PNIPAM).

This review presents our researches on the preparation and material application of inclusion complexes that comprises an amylose host and polymeric guests through phosphorylase-catalyzed enzymatic polymerization. Amylose is a well-known polysaccharide and forms inclusion complexes with various hydrophobic small molecules. Pure amylose is produced by enzymatic polymerization by using α-d-glucose 1-phosphate as a monomer and maltooligosaccharide as a primer catalyzed by phosphorylase. We determined that a propagating chain of amylose during enzymatic polymerization wraps around hydrophobic polymers present in the reaction system to form inclusion complexes. We termed this polymerization “vine-twining polymerization” because it is similar to the way vines of a plant grow around a rod. Hierarchical structured amylosic materials, such as hydrogels and films, were fabricated by inclusion complexation through vine-twining polymerization by using copolymers covalently grafted with hydrophobic guest polymers. The enzymatically produced amyloses induced complexation with the guest polymers in the intermolecular graft copolymers, which acted as cross-linking points to form supramolecular hydrogels. By including a film-formable main-chain in the graft copolymer, a supramolecular film was obtained through hydrogelation. Supramolecular polymeric materials were successfully fabricated through vine-twining polymerization by using primer-guest conjugates. The products of vine-twining polymerization form polymeric continuums of inclusion complexes, where the enzymatically produced amylose chains elongate from the conjugates included in the guest segments of the other conjugates.

Thermoresponsive ultrathin hydrogels were prepared by the sequential chemical reaction of poly(vinylamine-co-N-vinylisobutyramide) [poly(VAm-co-NVIBA)] and poly(acrylic acid) (polyAAc) on a gold surface. The carboxyl group of polyAAc was activated by 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride (EDC) for the reaction with the amino group of poly(VAm-co-NVIBA) to yield the amide linkage. This stepwise assembly was analyzed quantitatively by a quartz crystal microbalance (QCM), which revealed that the 39 mol % VAm content of poly(VAm-co-NVIBA) was suitable for the preparation of ultrathin hydrogels. A detailed analysis was performed by the assembly of poly(VAm-co-NVIBA), with a 39 mol % VAm content and polyAAc. The reflection−absorption spectra (RAS) showed the presence of both polymers in the assembly. Atomic force microscopic (AFM) observations confirmed the hydrogel structure of the assembly; the thickness of the hydrogel in an aqueous medium (around 320 nm) was 2 times greater than that...

In this study, we found that hierarchically controlled assemblies from amylose analog aminopolysaccharides occurred by reductive amination to obtain nanoparticles, microaggregates, and macrohydrogels depending on reaction conditions. The polysaccharide substrate composed of α(1→4)-linked glucosamine residues was synthesized by thermostable phosphorylase (from Aquifex aeolicus VF5)–catalyzed enzymatic polymerization of α-d-glucosamine 1-phosphate according to the reaction manner reported in our previous study. The reductive amination of the produced polysaccharide was carried out in the presence of NaBH3CN as reductant in 0.1 mol/L acetic acid aq. at 60 °C for 1 h. When lower feed ratios of reductant to the reducing end of the substrate were employed for the reaction, nanoparticles were obtained. With increasing feed ratios of reductant, more α(1→4)-GlcNn molecules assembled to further form water-insoluble microaggregates and macrohydrogels. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45890

This paper describes the evaluation of the stability of amylose-polymer inclusion complexes under solution state in dimethyl sulfoxide (DMSO) depending on guest polymers. The three complexes were prepared by the vine-twining polymerization method using polytetrahydrofuran (PTHF), poly(ε-caprolactone) (PCL), and poly(l-lactide) (PLLA) as guest polymers. The stability investigation was conducted at desired temperatures (25, 30, 40, 60 °C) in DMSO solutions of the complexes. Consequently, the amylose-PTHF inclusion complex was dissociated at 25 °C, while the other complexes were stable under the same conditions. When the temperatures were elevated, the amylose-PCL and amylose-PLLA complexes were dissociated at 40 and 60 °C, respectively. We also found that amylose inclusion supramolecular polymers which were prepared by the vine-twining polymerization using primer-guest conjugates formed films by the acetylation of amylose segments. The film from acetylated amylose-PLLA supramolecular polymer had higher storage modulus than that from acetylated amylose-PTHF supramolecular polymer, as a function of temperature.

(Apo)ferritins are cage-shaped proteins which have recently received a great deal of attention because the inner cavity of the protein shell can be used as a size-restricted reaction field for the synthesis of nanomaterials. The biomineralization behavior and inorganic nanoparticle (NP) synthesis mechanism of (apo)ferritin in solution systems have been studied but the mineralization behavior of (apo)ferritin on the substrates has not yet been well studied. Here, we conducted quantitative and kinetic analyses of the mineralization behavior of immobilized (apo)ferritin on a polyelectrolyte multilayer (PEM) using quartz crystal microbalance (QCM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. We demonstrated that the (apo)ferritin immobilized on a substrate synthesizes a ferrihydrite core within the confines of the protein cage; similar to a solution dispersed system. In addition, we applied a ferritin/apoferritin blended monolayer to the study of iron mineralization and revealed that biomineralization in this system is spatially selective. It is important to understand the mineralization mechanisms for the synthesis of other functional NPs as this approach has potential for a broad range of magnetic, catalytic, and biomedical sensing applications.

This article reports the enzymatic synthesis of dendritic amphoteric α-glucans having both glucuronic acid and glucosamine residues at the non-reducing ends by thermostable phosphorylase-catalyzed successive glucuronylation and glucosaminylation of a glucan dendrimer having α-(1 → 4)-glucan non-reducing ends using α-D-glucuronic acid 1-phosphate and α-D-glucosamine 1-phosphate as glycosyl donors, respectively. The structure of the products is confirmed by the (1)H NMR analysis. The products exhibit inherent isoelectric points (pIs) determined by the ζ-potential measurement. These materials self-assemble in water at pH = pI to form large aggregates, but disassemble at pH shifted from pI.

Melt transcription molding is one of novel processes suitable for manufacturing large-area thin film with microstructures. We designed the mold which enables to transfer structures on both surfaces for the melt transcription molding machine and examined about relations of temperature and pressure on the accuracy of dimension and optical strain. To keep the high accuracy of relative position between both surfaces, the mold can avoid strain caused by the thermal expansion of metal and is optimized by three-dimension unsteady heat conduction analysis. As a result, distribution of pressure mainly affects stress and distribution density, influences shrinkage and accuracy of position. The decenter between both surfaces was several micrometers. This makes it possible to mass-produce the large-area optical elements which is formed the micro and nano structures on both surfaces with extremely low birefringence at high productivity.

The thermoresponsive and pH-responsive intelligent copolymers of N-vinylformamide (NVF) and N-vinylisobutyramide (NVIBA), and their derivatives with primary amino groups, were synthesized. Hydrolys...

Signalling via the CD43 and CDw60 epitopes has been reported as providing two novel pathways of T-lymphocyte activation. In Wiskott-Aldrich syndrome, which has atopic eczema-like skin symptoms, there is a defective expression of CD43, while CDw60 is strongly expressed on T cells from rheumatoid arthritis synovial fluid and from psoriatic skin lesions, and on blood mononuclear cells from patients with cutaneous T-cell lymphoma. We therefore studied the expression and function of these phenotypes on peripheral blood mononuclear cells and on CD4+ and CD8+ T-cell subsets from patients with atopic dermatitis. We observed a significant increase in the percentage of CD43+ cells among the blood mononuclear cells in patients with atopic dermatitis and an enhanced proliferation of CD4+ T cells following stimulation with anti-CD43 antibody. There were no changes in the CDw60 expression or function after stimulation with anti-CDw60 antibody. Thus, CD43 expression was not decreased but rather increased in blood mononuclear cells from patients with atopic dermatitis, whereas CDw60 expression did not differ from healthy controls.

The mechanical properties of (U 0.8− x Ce 0.2 M x )O 2 [M: Nd (0≤ x ≤0.13) or Zr (0≤ x ≤0.06)] were studied. The longitudinal and shear sound velocities were measured by an ultrasonic pulse–echo method at room temperature, which enabled us to evaluate the elastic properties and Debye temperature. The microhardness measurement was performed at room temperature using a micro-Vickers hardness tester. The elastic moduli such as Young’s modulus and shear modulus decrease with increasing M atoms content. The values of micro-Vickers hardness and yield stress also decrease with increasing M atoms content.

The three-dimensional finite element (3D FE) methods have been used increasingly to evaluate the bearing capacity of pavement structures. In this evaluation, layer moduli are backcalculated from measured surface deflections of the pavement structure. However, backcalculation requires repetitive computation to improve the parameter values in an iterative manner, and thus it is time consuming when 3D finite elements are used for the analysis. In this article, an effective method is developed to estimate layer moduli and damping coefficients in the time domain. The pavement is modeled using 3D finite elements. Gauss—Newton and singular value decomposition methods are employed to backcalculate the unknown parameters. Ritz vectors are used to reduce the size of the matrices required for the analysis. Numerical simulations verify the effectiveness and accuracy of the Ritz vector method. Acknowledgements and Notes. All correspondence should be addressed to Q. Dong. Postdoctoral Fellowships for Foreign R...

The thermal conductivities of (U 0.8− x Ce 0.2 M x )O 2 [M: Nd (0⩽ x ⩽0.13) or Zr (0⩽ x ⩽0.06)] were evaluated from the thermal diffusivity measured by the laser flash method. The thermal conductivities of (U 0.8− Ce 0.2 M x )O 2 indicated a systematic decrease with increasing M-atom content at all temperatures from 200 to 1500 K. In addition, the thermal conductivities of all samples decreased with increasing temperature up to about 1000 K. Up to about 1000 K, the thermal conductivity of (U 0.8− x Ce 0.2 M x )O 2 could be expressed as a function of M-element content by the phonon conduction equation.

In order to develop new techniques to calculate the physicochemical properties of MOX fuel, molecular dynamics methods were applied to UO2, PUO2, and (U,Pu)O2. These methods enabled us to obtain the heat capacity and thermal conductivity from basic properties, viz., the lattice parameter, linear thermal expansion coefficient, and compressibility. Results for UO2 showed both the existence of a Bredig transition and a peak in the heat capacity at high temperature. The lattice parameter, heat capacity, and thermal conductivity of MOX fuel were calculated from basic properties of UO2 and PuO2. These results showed that molecular dynamics techniques can be usefully applied to determine physicochemical properties of MOX fuel.

Four patients had the clinical features of 'ampulla cardiomyopathy', consisting of acute-onset transient left ventricular apical akinesis with basal normokinesis, normal coronary angiogram, ST-segment elevation and subsequent giant T wave inversion, which mimicked acute coronary syndrome, the onset of which occurred shortly after extreme mental stress. Myocardial necrosis was minimal, although 2 patients showed elevated serum catecholamine levels in the acute phase. Each patient underwent serial cardiac radionuclide single-photon emission computed tomography of myocardial functional sympathetic innervation, fatty acid metabolism and perfusion using I-123-metaiodobenzyl-guanidine (MIBG), I-123-beta-metyl-iodophenyl pentadecanoic acid (BMIPP) and thallium-201 (201Tl), respectively. In the acute phase, MIBG and BMIPP imaging showed an uptake defect in the apical region, whereas 201Tl uptake was mildly decreased. When assessed semi-quantitatively, the MIBG images had higher defect scores from the acute phase throughout the year of observation compared with BMIPP, and 201Tl. These observations suggest that the primary cause of ampulla cardiomyopathy is related to a disturbance of the cardiac sympathetic innervation.

In this study, we synthesized an amphiphilic polyhedral oligomeric silsesquioxane (POSS) having controlled numbers of hydrophilic and fluorescent hydrophobic groups (seven and one, respectively) by...