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Dynamical localization that is, reduction of the intersite electronic transfer integral, was realized by strong electric filed (10 MV/cm) of 1.5-cycle (7 fs) near infrared light in layered organic conductor.

We consider certain matricial analogues of optimal mass transport of positive definite matrices of equal trace. The framework is motivated by the need to devise a suitable geometry for interpolating positive definite matrices in ways that allow controlling the apparent tradeoff between "aligning up their eigenstructure" and "scaling the corresponding eigenvalues". Indeed, motivation for this work is provided by power spectral analysis of multivariate time series where, linear interpolation between matrix-valued power spectra generates push-pop artifacts. Push-pop of power distribuion is objectionable as it corresponds to unrealistic response of scatterers., Comment: 4 pages, 6 figures

This paper studies the problem of passive control of a multi-storey building subjected to an earthquake disturbance. The building is represented as a homogeneous mass chain model, i.e., a chain of identical masses in which there is an identical passive connection between neighbouring masses and a similar connection to a movable point. The paper considers passive interconnections of the most general type, which may require the use of inerters in addition to springs and dampers. It is shown that the scalar transfer functions from the disturbance to a given inter-storey drift can be represented as complex iterative maps. Using these expressions, two graphical approaches are proposed: one gives a method to achieve a prescribed value for the uniform boundedness of these transfer functions independent of the length of the mass chain, and the other is for a fixed length of the mass chain. A case study is presented to demonstrate the effectiveness of the proposed techniques using a 10-storey building model. The disturbance suppression performance of the designed interconnection is also verified for a 10-storey building model which has a different stiffness distribution but with the same undamped first natural frequency as the homogeneous model.

A strong electron–phonon coupling effect, referred to as electron–molecular vibration (e–mv) coupling, induces characteristic vibronic signals in the vibrational spectra of organic conductors. This paper discusses a new spectroscopic signal induced by the e–mv coupling effect, and the physical implications of its emergence. This vibronic signal, attributable to an overtone of a molecular vibration, appears with an anti-resonance form in the infrared spectrum of some mixed-valency complexes when the compounds undergo a charge-ordering transition. Based on the results of cluster model calculations, the activation of the overtone signal is interpreted as an indication of the generation of anharmonicity in the electronic potential. This analysis suggests that the series of the complexes should possess potential nonlinear optical abilities, though these compounds have long been viewed as electric conductors having the opposite characteristics of dielectrics that show nonlinear optical properties.

Low temperature measurements of optical second-harmonic generation (SHG) were performed for organic conductors showing ferroelectric charge ordering. To avoid the heating due to focused laser beam without applying mechanical stress to the samples, the organic crystals were mounted in liquid argon heat-transfer medium. The noble gas was sealed in a diamond-anvil cell type pressure cell, though the pressure was regulated around ambient level. The technique of the low temperature nonlinear optical microscopy is presented. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The carbide and graphite formation and redistribution of alloy elements during solidification were investigated on high-speed steel (HS) and Ni-hard type cast irons with Nb and V. The crystallization of hypereutectic HSS proceeds in the order of primary MC, γ + MC, γ + M6C, γ + M7C3, and γ + graphite eutectic, in hypoeutectic alloys proceeds in the order of primary γ, γ + MC, γ + graphite, γ + M6C, and γ + M7C3 eutectic, and in Ni-hard proceeds in the order of primary γ, γ + MC, γ + M3C, and γ + graphite eutectic. The γ + graphite eutectic solidifies with the decrease of V, Nb, and Cr and the increase of Si and C contents in residual liquid during solidification. The behavior in graphite forming tendency in the residual liquid is estimated by the parameter ∑CLimi′. The eutectic graphite crystallizes at the solid fraction when ∑CLimi′ takes a minimum value. The amount of graphite increases with the decrease in ∑CLimi′ of initial alloy content in both specimens. Inoculation with ferrosilicon effectively increases the graphite content in both specimens.

The influence of Ta addition on the solidification microstructure, solute distribution and hardness after quenching and tempering treatments was investigated for a high-carbon high-speed steel type cast alloy (Fe–1.9%C–0.5%Mn–4.9%Cr–5.0%Mo–5.0–7.2%V–0.4–1.4%Ta). The compositions of V and Ta were systematically changed to improve the distribution of hard MC carbides in the hypoeutectic range. Electron probe micro-analysis (EPMA) and X-ray diffraction (XRD) identified an oval microstructure as MC carbides containing mainly V and Ta, and a lamellar structure as M2C carbides containing mainly Fe and Mo among the austenite (γ) dendrites. Redistribution of alloying elements during the solidification sequence of primary γ, γ + MC and M2C eutectic structure could be calculated from the Scheil-Gulliver equation and the initial composition. The macro-hardness of the quenched specimens gradually increased with increasing quenching temperature until a maximum was reached. This indicates that macro-hardness of the quenched specimens depends on both the amount and hardness of martensite matrix. All specimens which were tempered at 723–873 K showed secondary hardening. Furthermore, hardening of the specimens was most apparent when specimens containing large amounts of retained γ were tempered at an optimum temperature. For example, the hardness of specimens with added Ta increased to around 900 HV after tempering at 823 K. These results suggest that the macro-hardness of tempered specimens is governed by the maximum amount of carbon in the γ matrix at quenching temperature, the degree of transformation from retained γ to martensite, and the precipitation and distribution of secondary carbides.

Both Re2C and Re2N are ultra incompressible and have a bulk modulus of about 400 GPa. These materials are synthesized under high pressure and high temperature. The synthesis pressures are about 10 GPa or below for Re2C and 20–30 GPa for Re2N. If the synthesis pressure of Re2N was about 10 GPa or below, a large volume high-pressure cell like a multi-anvil apparatus can be used to synthesize Re2N. To realize this, a proper solid nitrogen source is needed instead of liquid or gas nitrogen. We used a precursor of a mixture of rhenium and home-made nanoscale amorphous two-dimensional carbon nitride as a solid nitrogen source. Consequently, the synthesis reaction produced Re2C but not Re2N. We characterized the synthesized Re2C by various techniques including high-pressure x-ray diffraction (XRD). The bulk modulus B0 of the synthesized Re2C under hydrostatic conditions was estimated to be 385.7 ± 18.0 GPa. This value is a little smaller than the previous data. When the pressure medium became non-hydrostatic, the peculiar compression behaviour occurred; the rate of broadening of XRD lines increased and the compression became negligible in the range of a few GPa. The reason for this peculiar behaviour is not known.

For primary organ preservation, concurrent chemoradiotherapy (CCRT) is performed for advanced squamous cell carcinoma of the head and neck (SCCHN). In this organ-preservation setting with CCRT, surgery is reserved as a salvage treatment in cases of locoregional failure after CCRT. The purpose of the study was to review our experience with salvage surgery after CCRT for patients with SCCHN and to evaluate the effectiveness and prognostic factors affecting survival. The records of patients with stage II-IVB SCC of the larynx, oropharynx, or hypopharynx treated with salvage surgery after CCRT between 1998 and 2012 were reviewed. A total of 645 patients with previously untreated, resectable SCC of the larynx, oropharynx, or hypopharynx received CCRT. Salvage surgery was performed for 78 of 225 patients with residual or recurrent tumors. The 5-year overall survival (OS) and disease-specific survival rates for patients who received salvage surgery were 61.0 and 65.5 %, respectively. Stage IV, poorly differentiated, synchronous double cancer, and surgical complications were significant predictors of unfavorable OS on multivariate analysis. Postoperative complications were observed in 30 patients (38.5 %). Salvage surgery is the best therapeutic option for failure after CCRT for SCCHN because of its good survival rate, although a high surgical complication rate is seen. Patients with initial stage IV tumors, poorly differentiated SCC, or synchronous double cancer are considered for further adjuvant treatment.

Cutting performance of cemented carbide drills with various coatings was investigated in detail under minimum quantity lubrication (MQL) conditions. An advanced dual-channel Bielomatik MQL system was installed in an Okuma machining center. A specially designed Mapal drill was selected for the studies to eliminate voids between the tool and the MQL tool holder that can interfere with mist delivery. Using this design, a mist flow rate of 25 mL/min was achieved through the drills. Progressive frictional/wear studies were performed. Coated drills were tested in three stages (50, 500, and 7000 holes). During short term drilling tests (50-hole level), cutting performance was comprehensively evaluated for a range of coatings by measuring several in-situ frictional characteristics of the cutting process, such as cutting forces, and related characteristics including, chip type and undersurface morphology. Wear patterns of the cutting tools were indentified as well. Selected coatings were tested further. The best cutting performance based on the 500-hole testing was found with the diamond coating. However, excessive brittleness of the entire coating/substrate system led to premature failure of the drill after 4300 holes. The low-hydrogen DLC coating that also showed promising cutting performance based on the 500-hole test was selected as the next candidate for further testing. Drills with low-hydrogen DLC coating achieved 7200 drilled holes with a flank wear of only 110 μm and moderate intensity of workpiece material pickup. This results in a better surface finish of drilled holes. Based on this study, the Mapal drills with the low-hydrogen DLC coating provided comparable machining performance to that possible with traditional wet machining, but with the environmental and cost advantages possible with MQL.

It is indicated that total/HDL cholesterol and LDL/HDL cholesterol ratios have more predictive power for cardiovascular disease compared to classic lipid parameters. However, there have been few reports about the usefulness of these indices for the assessment of early stage atherosclerosis in Japanese type 2 diabetic subjects.We examined the relation between various lipid parameters and carotid atherosclerosis in 934 type 2 diabetic subjects without apparent atherosclerotic diseases (males, 71.7%; age, 59.6 ± 10.5 years (mean ± SD)). Serum concentrations of total cholesterol (TC), HDL cholesterol (HDL-C), and triglyceride were measured. LDL cholesterol (LDL-C) level was calculated using the Friedewald formula. The presence of carotid plaque and intima-media thickness (IMT) were evaluated by ultrasonography.A stepwise multivariate regression analysis demonstrated that HDL-C (β = -0.110, p0.001), TC/HDL-C (β = 0.132, p0.001) and LDL-C/HDL-C ratios (β = 0.132, p0.001) were independent determinants of IMT even after adjustment of other conventional risk factors. However, there was no significant correlation between IMT and TC, triglyceride, LDL-C, and non-HDL-C levels. TC/HDL-C and LDL-C/HDL-C ratios and non-HDL-C levels were significantly higher, but HDL-C levels were significantly lower in patients with carotid plaque than those without it (p0.05). There was no significant difference between the groups regarding TC, LDL-C, and triglyceride levels. Furthermore, TC/HDL-C (OR; 1.34, p0.001) and LDL-C/HDL-C (OR; 1.54, p0.001) ratios showed a positive and linear relationship with the prevalence of carotid plaque, whether covariates were adjusted or not.TC/HDL-C and LDL-C/HDL-C ratios are useful as a tool to assess the risk of early stage atherosclerosis in Japanese type 2 diabetic patients.

Passive dampers are used recently in many mid and high-rise buildings. This trend is accelerated by the increased demand and desire for safer, more reliable and more comfortable buildings under uncertain external loading and environment. Viscous, visco-elastic, hysteretic and friction dampers are representatives of passive dampers. Such passive dampers also play a key role in the implementation of structural rehabilitation which is essential for the realization and promotion of sustainable buildings. The technique of structural health monitoring is inevitable for the reliable and effective installation of passive dampers during the structural rehabilitation or retrofit. The design earthquake ground motions change from time to time when a new class of ground motions (e.g. long-period ground motions due to surface waves) is observed or a new type of damage appears during severe earthquakes. The concept of critical excitation is useful in responding to this change together with the usage of passive dampers from the viewpoint of sustainable buildings and cities. In this paper, a historical review is made on the development of smart or optimal building structural control with passive dampers and some possibilities of structural rehabilitation by use of passive dampers are discussed.

Objective: Progressive β-cell dysfunction and loss of β-cell mass are fundamental pathogenic features of type 2 diabetes. To examine if anti-diabetic reagents, such as insulin, pioglitazone (pio), and alogliptin (alo), have protective effects on β-cell mass and function in vivo, we treated obese diabetic db/db mice with these reagents. Methods: Male db/db mice were treated with a chow including pio, alo, or both of them from 8 to 16 weeks of age. Insulin glargine (gla) was daily injected subcutaneously during the same period. Results: At 16 weeks of age, untreated db/db mice revealed marked increase of HbA1c level, whereas those treated with pio, pio + alo, or insulin revealed the almost same HbA1c levels as non-diabetic db/m mice. Islet mass evaluated by direct counting in the whole pancreas and insulin content in isolated islets were preserved in pio, pio + alo and gla groups compared with untreated or alo groups, and there was no difference among pio, pio + alo and gla groups. To precisely evaluate islet β-cell functions, islet perifusion analysis was performed. In pio, pio + alo and gla groups, biphasic insulin secretion was preserved compared with untreated or alo groups. In particular, pio + alo as well as gla therapy preserved almost normal insulin secretion, although pio therapy improved partially. To examine the mechanism how these reagents exerted beneficial effects on β-cells, we evaluated expression levels of various factors which are potentially important for β-cell functions by real-time RT-PCR and immunohistochemistry. The results showed that expression levels of MafA and GLP-1 receptor were markedly decreased in untreated and alo groups, but not in pio, pio + alo and gla groups. Conclusion: Combination therapy with pio and alo almost completely normalized β-cell functions in vivo, which was comparable with gla treatment.

A series of abrasion tests on high Cr-V-Nb cast irons revealed that the addition of MC type carbide formers, V and Nb, remarkably enhances the abrasion resistance of high Cr cast iron, and the abrasion resistance becomes higher with the increase in MC type carbides[1]. Therefore, hyper eutectic Fe-4.7%C-15%Cr-7%V-5%Nb-5%Mo alloy melt was poured into 30kg and 1kg sand mold castings to distribute different sizes of primary and eutectic carbides in hardenable matrix. The abrasion test specimens cut from each casting were austenitized at 1323K for 1h then cooled in air. These specimens were tempered at 773K for 1h followed by air cooling. The hardness of specimens was 1015-1018HV50. The rubber wheel abrasion test, a typical 3 body type one, was performed on these quenched and tempered specimens with 56-107, 107-150 and 297 μm dia. silica grit. The testing load was 86.3N and 172.5N, and the rubber wheel rotation speed was varied from 1s-1 to 4s-1. Though the higher testing load increases the wear loss, the wear rate expressed by the wear volume/( testing load × wear distance) changes depending on the wear condition and the microstructure. In case of 30kg cast specimen, the silica grit preferentially attack and scrape off the matrix, and the wear rate increases with the increase in the testing load. The fine carbides in 1kg cast specimens effectively protect the matrix from the attack of silica grit, and the wear rate decreases with increasing load which causes silica grit blunt and fracture. However, fine carbides tend to be fractured by silica grit and diminish the protective effect. Based on the worn surface structures, the abrasion mechanism is discussed comparing those of steel and eutectic 25%Cr cast iron.

Sharp changes in the integral intensity and linewidth of the ESR spectrum that accompany the localization of the charge carriers have been revealed in α’-(BEDT-TTF)2IBr2 crystals. It has been found that the types of localization in two compounds under investigation are different: charge carriers in β″-(BEDT-TTF)4NH4[Cr(C2O4)3] are localized on irregular defects of the crystal lattice, whereas charge carriers in α’-(BEDT-TTF)2IBr2 are localized at the regular positions of the unit cell. The exchange narrowing of the ESR line and a sharp decrease in the dc and ac magnetic susceptibilities are observed in α’-(BEDT-TTF)2IBr2 at low temperatures T 50 K differ from each other, because the thermally activated hopping frequency of the charge carriers is higher than the frequency of the measuring UHF field of an ESR spectrometer.

A gradient-based evolutionary optimization methodology is presented for finding the optimal design of viscous dampers to minimize an objective function defined for a linear multi-storey structure. The maximum value along height of the transfer function amplitudes for the interstorey drifts is taken as the objective function. Since the ground motion includes various uncertainties, the optimal damper placement may be different depending on the ground motion used for design. Furthermore, the transfer function treated as the objective function depends on the properties of structural parameters and added dampers. This implies that a more robust damper design is desired. A reliable and robust damping design system against any unpredictable ground motions can be provided by minimizing the maximum transfer function. Such design system is proposed in this paper.

A multi-functional nano-multilayered Ti0.2Al0.55Cr0.2Si0.03Y0.02N/Ti0.25Al0.65Cr0.1N physical vapor deposited (PVD) adaptive hard coatings is presented. This novel coating consists of alternating layers with variable chemical composition but similar crystal structure and hardness. A comprehensive investigation of the microstructure and properties of the coating was performed. The structure of the coating before and after service has been characterized by high-resolution transmission electron microscopy (HRTEM). Various micro-mechanical characteristics (hardness, impact fatigue fracture resistance, and low cycling wear resistance) of the coating have been investigated. Oxidation resistance of the coating has been studied using Thermogravimetric–Differential Thermal Analysis (TG-DTA) within a temperature range of 25–1200 °C in air. Wear performance of the novel TiAlCrSiYN/TiAlCrN coating was evaluated through tool life studies, cutting forces measurements and identification of chips characteristics. To determine the causes of improvement in wear performance, the worn surface of the coated cutting tools was investigated using SEM/EDS. The characteristics of the surface tribo-films that were formed on the worn surface were studied using, X-ray photoelectron spectroscopy (XPS) and Extended Energy-loss Fine Spectroscopy (EELFS). One of the major features of this coating is enhanced formation of tribo-oxide films on the surface during friction. These oxides possess a sapphire and mullite structure with superb protective ability that acts simultaneously with high temperature lubricious Si–O and Cr–O phases. Due to emergent properties, the developed adaptive coating behaves as a higher ordered system under operation, capable of sustaining extreme operating conditions.

Machining of aerospace materials is one of the major challenges of modern manufacturing. Application of nano-multilayered AlTiN/Me x N PVD coatings (where Me x is a transition metal of V–VI groups of periodic table) to cemented carbide tooling results in a significant tool life improvement under conditions of cutting hard to machine alloys such as Ni-based Inconel 718 superalloy and Ti-based TiAl6V4 alloy. Microhardness and coefficient of friction of the coatings were measured during this experiment. Investigations of the coated tool life, wear behavior, chip formation (chip type and undersurface morphology) for cutting tools with nano-multilayered PVD coating were also performed. Morphology of worn tools has been studied using SEM and EDX. This study will show that metallurgical design of the nano-multilayered coating should be tailored to its application. To achieve better tool life when machining Inconel 781, adaptive nano-multilayered AlTiN/MoN coating is recommended, whereas a AlTiN/VN coating is better suited to machining TiAl6V4 alloy. A driving force behind selecting these coatings was a noticeably lower coefficient of friction at elevated temperatures.

New nano-multilayered TiAlCrSiYN/TiAlCrN coatings have been developed with various ratios of Ti/Al/Cr within Si + Y containing nano-layers. The layered nanostructure of the coatings has been studied by STEM-HAADF mode and the nano-metric composition obtained by in-situ EDS. Micro-mechanical characteristics were investigated using a Micro Materials NanoTest System. Thermogravimetric-Differential Thermal Analysis (TG-DTA) was used within a temperature range of 25–1200 ° C for oxidation resistance evaluation. The wear performance of nano-multilayered TiAlCrSiYN/TiAlCrN coatings during machining of direct aged Inconel (DA) 718 and powder metallurgical ME 16 Ni-based superalloys has been investigated. The kinetic coefficient of friction under metal cutting conditions of Inconel was measured. The temperature range was 25–1000 ° C. It was shown that the composition of the nano-multilayered coatings and their characteristics have to be tuned for specific applications. A nano-multilayered coating with increased amount of Al (60 at.%) in Si + Y containing nano-layers that has strong oxidation resistance and a higher range of micro-mechanical properties related to crack propagation under scratch conditions behaves better during machining of Inconel DA 718 alloy. For machining of the more high temperature strong and thermally resistant ME 16 superalloy, a nano-multilayered coating with less Al (55 at.%) in Si + Y containing nano-layers that combines improved oxidation resistance with higher hardness and other beneficial micro-mechanical properties associated with resistance to plastic deformation performs best.

The kinetic energy of α′-(BEDT-TTF)2IBr2, α-(BEDT-TTF)2I3, and α-(BEDT-TTF)2NH4Hg(SCN)4 was estimated from the room-temperature optical conductivity measured from 50 to 30 000 cm−1. The kinetic energy of α′-(BEDT-TTF)2IBr2 was significantly smaller than that of α-(BEDT-TTF)2I3 that shows metal–insulator phase transition. A clear hysteresis was found in the magnetic susceptibility near the phase transition at around 30 K.

Machining of Ni-based aerospace alloys is one of the major challenges of modern manufacturing. Application of cemented carbide tooling with nano-multilayered AlTiN/Cu PVD coating results in a significant tool life improvement under conditions of turning the hard-to-machine aerospace Ni-based Inconel 718 superalloy. Studies of the structure, properties, tribological and wear performance of the nano-multilayered AlTiN/Cu PVD coating have been performed. The structure of the coating has been investigated using High Resolution Transmission Electron Microscopy. Various properties of the coating including microhardness, thermal conductivity and coefficient of friction vs. temperature were measured. Investigations of the coated tool life, wear behavior and chip formation for cutting tools with nano-multilayered AlTiN/Cu PVD coating were performed. Morphology of the worn tools has been studied using SEM/EDX. AlTiN/Cu coatings present multi-functionality because they combine self-lubricating behavior with reduced thermal conductivity. This beneficial combination of properties results in significant improvement of the coated tool life.

The time-domain waveform of the terahertz (THz) electric field emitted from the charge-ordered organic ferroelectrics α − (ET)2I3 [ET:bis(ethylenedithio)-tetrathiafulvalene)] can be significantly modulated depending on incident fluence of femtosecond pulses. Weak irradiation triggers the emission, showing ∼1 THz oscillation in the time-domain waveform with more than 5 oscillation cycles and a corresponding narrow spectral shape. In contrast, strong irradiation almost completely suppresses the trailing portion of the waveform after the first cycle, resulting in over 3 times broader bandwidth. As revealed by time-resolved experiments, this modulation arises from the cooperative nature of photoinduced melting of the charge order accompanying quenching of infrared-activity of the intermolecular vibrations which strongly couple with the emission.

Nano-crystalline TiAlCrSiYN plasma vapor deposited (PVD) coatings were developed for oxidation and wear protection at elevated temperatures. Compositional tuning of the coatings was performed to enhance oxidation protection at elevated temperatures. The oxidation kinetics of the coatings has been studied over 180 h at 900 °C in air. Post-oxidation microstructural examinations of specimens were performed using transmission electron microscopy (TEM), secondary electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and glow discharge optical emission spectroscopy (GDOES). Micro mechanical characteristics of the coating were studied using a micro materials nanotest system. Wear resistance of the coatings were studied during turning of Inconel 718. Experimental results clearly indicate that the aluminum-rich PVD TiAlCrSiYN coatings with 60 at.% of Al can improve oxidation resistance of titanium aluminide alloy at the temperature 900 °C as well as wear resistance during machining of Inconel 718. It was shown that during oxidation, continuous protective alumina-based oxide films form on the surface. These oxides are predominantly (Al,Cr)2O3-based films. Self-healing behavior of the TiAlCrSiYN coatings was observed in its ultra-fine nano-crystalline structure.

This paper aims to obtain an optimal viscous damper placement for building structures using H∞ optimization. The H∞ norm of the transfer function matrix is adopted as the objective function. Since it represents the magnitude of vibration transfer, one can attenuate the gain of the frequency response by minimizing this norm. The sequential quadratic programming (SQP) method is employed for optimization. The proposed method is also applicable to a various structural models as well, e.g., a bending-shear building model and a framed structure model. Numerical examples are presented to demonstrate the effectiveness of the proposed design method.

Machining of hard to cut materials such as hardened steels and high temperature strong aerospace materials is a challenge of modern manufacturing. Two categories of the aluminum-rich TiAlN-based Physical Vapor Deposited (PVD) coatings, namely AlTiN and TiAlCrN, are commonly used for this area of application. A comparative investigation of the structural characteristics, various micro-mechanical properties, oxidation resistance and service properties of the both coatings has been performed. Crystal structure has been studied using High Resolution Transmission Electron Microscopy (HR TEM). Electronic structure has been investigated using X-ray Photoelectron Spectroscopy (XPS). Micro-mechanical properties (microhardness, plasticity index, impact fatigue fracture resistance) have been evaluated using a Micro Materials Nano-Test System. Short-term oxidation resistance has been studied at 900 °C in air. The tool life of the coating was studied during ball nose end milling of hardened H 13 tool steel as well as end milling of aerospace alloys such as Ni-based superalloy (Waspalloy) and Ti alloy (TiAl6V4). It was shown that the set of characteristics that control wear performance strongly depend on specific applications. For machining of hardened tool steels, when heavy loads/high temperatures control wear behavior, the coating has to possess a well-known combination of high hot hardness and improved oxidation resistance at elevated temperatures. To achieve these properties, crystal structure for TiAlN-based coatings should be mainly B1, and elemental composition of the coating should ensure formation of strong inter-atomic bonds such as Al–Cr metal-covalent bonds in the TiAlCrN coating. Nano-crystalline structure with grain size of around 10–30 nm enhances necessary properties of the coating. In contrast, for machining of aerospace alloys, when elevated load/temperature combined with intensive adhesive interaction with workpiece material results in unstable attrition wear with deep surface damage, the coating should possess a different set of characteristics. Crystal structure for TiAlN-based coatings is basically B1; but due to a high amount of aluminum, the AlTiN coating contains AlN domains. The coating has a very fine-grained nano-crystalline structure (grains sized around 5 nm). Electron structure of energy levels indicates formation of metallic bonds. This results in plasticity increase at the cost of hot hardness reduction. The surface is able to dissipate energy by means of plastic deformation (instead of crack formation) and in this way, surface damage is reduced.

The input energy and energy input rate to a base-isolated (BI) building during an earthquake are considered and formulated in the frequency domain. The frequency-domain approach for computation of input energy and energy input rate has different remarkable advantages compared with the conventional time-domain approach. It is demonstrated that the input energy can be of a compact form via the frequency integration of the product between the input component (squared Fourier amplitude spectrum of acceleration) and the structural model component (so-called energy transfer function). Furthermore, the energy input rate can also be of a similar form via the frequency integration of the product between the instantaneous power spectrum and the energy transfer function. With the help of this compact form, it is shown that the formulation in the frequency domain is essential for deriving arbitrary-order closed-form sensitivities of the input energy and energy input rate with respect to uncertain stiffness and damping coefficients in the BI storey. The closed-form sensitivity expressions provide us with information on the most unfavourable variation of the uncertain parameters that leads to the maximum input energy and input rate. Copyright © 2009 John Wiley & Sons, Ltd.

The microstructure and electronic structure of nanodispersed (Al 67 Ti 33 N) and (Ti 10 Al 70 Cr 20 N) PVD coatings were investigated by high-resolution transmission electron microscopy (HRTEM) and electron spectroscopy techniques: X-ray photoelectron spectroscopy (XPS) and high-resolution electron energy loss spectroscopy (HREELS). The grain size measured by HRTEM was 5–20 nm for Al 67 Ti 33 N and TiAlCrN type coatings, correspondingly. The spinodal decomposition of Al supersaturated nitrides under its deposition was found. Chromium increases the metastable solubility of h -AlN in c -Ti 1 − x Al x N. The lifetime of the cutting tools with Al-rich coatings has been evaluated under ball nose end milling of hardened tool steel H13 (HRC 50–52) and aerospace materials. TiAlCrN coatings are preferable for steel machining, and AlTiN coatings are better for aerospace material processing. It was found that AlTiN coating has lower hardness but higher plasticity and improved impact fatigue fracture resistance. The TiAlCrN coating has much better hot hardness and oxidation stability at high temperatures, but it is stiffer than AlTiN.

The purpose of this study was to investigate the effect of an increase in intramuscular pressure on ventilatory response at the onset of exercise. Seven subjects participated in this study. We measured ventilatory responses to a 20-s single-arm extension-flexion exercise and passive movement. Each subject performed two kinds of exercise and passive movement in random order: in one, the exercising arm was encircled with a deflated cuff placed around the upper arm; in the other, the exercising arm was compressed by a cuff placed around the upper arm, which was inflated to 25 mmHg. We found that neither ventilatory response during exercise nor during passive movement was significantly changed even though the cuff compressed the arm. In conclusion, the increased intramuscular pressure caused by the 25-mmHg pressure of the cuff did not have a significant influence on ventilatory response at the onset of exercise.

In (Fe, Ni)-Cr-C alloys, with Fe replaced by 25 mass%Ni-70 mass%Ni in high-chromium cast irons, the effects of Ni content on the solidification structure, solidification sequence, and liquidus surface diagram were investigated. The microstructures of alloys consist of matrix and M 7 C 3 carbides precipitated as primary and/or eutectic crystals. They resemble general high-chromium cast iron except for mostly austenitic matrix. According to EDS analyses of alloy contents in each phase of specimens, the Cr content in M 7 C 3 carbide increases concomitantly with increasing Ni content, but that in y exhibits almost no change. Solidification begins by crystallization of primary austenite (y) in hypoeutectic alloy and that of primary M 7 C 3 carbide in hypereutectic alloy. Either case is followed by precipitation of (y+M 7 C 3 ) eutectic. However, graphite precipitates from melt in the alloys with high-C or high-Ni content and its precipitation region shifts to the low-C-high-Cr side as the Ni content increases. The (y-M 7 C 3 ) eutectic line on the liquidus surface diagram moves strongly to the low-C side with increased Ni content, but it returns to the high-C side when Ni contents become greater than 50mass%. The diagrams produced using thermo-Calc software resemble those constructed based on experimental results.

The selection and the formation of carbide govern quality and the service life of hot steel milling rolls. Thus the microsegregation and the formation of the carbides and the graphite during the solidification have been investigated for high speed steel type cast iron and Ni-hard type cast iron. The crystallization of high speed steel type cast iron proceeds in the order of primary austenite (γ), γ+MC and γ+M2C eutectic. On the other hand, in Ni-hard type cast iron, eutectic graphite flakes can crystallize after the formation of primary γ, and γ+M3C eutectic by controlling the content of Ni and Si in spite of containing strong carbide formers such as Cr. As γ+carbide eutectic grows, the residual liquid among eutectic cells becomes rich or poor in carbide formers according the partition coefficient between residual liquid and eutectic cell. It is realized that the change of composition of carbide formers during the solidification is estimated with Scheil–Gulliver equation and computed phase diagrams in both of cast irons. The graphite forming tendency is also evaluated by applying the parameter, which expresses the solubility limit of carbon to the molten iron for Ni-hard type cast iron.

We previously reported that ventilatory response at the onset of light leg exercise was augmented in delayed onset muscle soreness (DOMS) after eccentric exercise (ECC) utilizing the leg. In this study, we examined whether the same result would appear in light exercise in which an arm with DOMS was utilized. Eleven subjects performed ECC using one arm, and we measured ventilatory responses to a 20-s single-arm extension-flexion exercise and to passive movement (PAS) before and 2 days after ECC (D2). We found that ventilatory response to both the exercise and PAS in which all subjects perceived DOMS was augmented at D2. It was concluded that initial hyperpnea, which occurred during arm exercise in DOMS, was enhanced, and from examining the result of PAS, enhanced initial exercise hyperpnea may be due in part to an exaggerated peripheral neural reflex.

Graphite formation should be strictly suppressed for the most abrasion resistant white cast irons, since austenite (γ)+graphite eutectic structure shows lower hardness and selectively wears thus deteriorates the abrasion resistance even though the austenite transform to hard phase such as martensite. On the other hand, a small amount of fine graphite is desired to distribute in rolls for hot steel mills to suppress the scoring. However, strong carbide formers such as Cr, V, Nb have been increasingly added to rolls, in order to crystallise more harder carbides. As γ+carbide eutectic grows, the residual liquid among eutectic cells becomes poor in carbide formers and rich in elements which promote graphite formation. Therefore an appropriate alloy design is essential for the hot steel milling rolls. In this study, the graphite formation mechanisms are discussed for chromium cast iron, high speed steel type cast iron and Ni hard type cast iron.

Primary dynamics of photo-induced melting of charge order (CO) and metallic domain formation in [bis(ethlylenedithio)] tetrathiafulvalene (BEDT-TTF) salts α-(BEDT-TTF)2I3 were studied using an infrared (1.4 μm) pump–probe spectroscopy with a time resolution of 30 fs. Faster (

Applications of quaternary nitride nanomultilayered coatings result in a significant improvement in tool life as well as wear behavior of ball nose end mills under conditions of high-speed machining of hardened steels. Features of self-organization in the nanostructuring monolayer (Al 67 Ti 33 )N and nanolaminate multilayer (AlCrTi)N/(CrN, WN or NbN) physical vapor deposition (PVD) coatings have been investigated under severe frictional conditions associated with high temperatures and stresses, which are typical for high-speed cutting (HSC). Structure and phase transformations on wear surface have been studied using XPS. Wear behavior of the coating has been investigated under severe conditions of HSC of 1040 steel. Results show that the enhancement of nonequilibrium processes during friction leads to a dominating formation of protective triboceramics on the basis of sapphire-like and tungsten and niobium polyvalent oxides with the structure that improves the wear performance critically.

Application of quaternary nitride nano-multilayered coatings results in significant improvements in tool life as well as wear behavior of ball nose end mills under severe conditions of dry high speed machining of hardened H13 steel (HRC 55–57). Tool life of different nano-multilayered TiAlCrN-based coatings with addition of transitional metals based (of V and VI groups) nitride layers has been compared. Tool life of TiAlCrN/NbN coating was found to be higher than compared to the other nano-multilayered coatings. Investigation of surface structure characteristics of the TiAlCrN/NbN coating using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) and High Resolution Electron Energy Loss Spectroscopy (HREELS) has been performed. The properties of the coatings such as microhardness, modulus of elasticity, coefficient of friction and oxidation stability at elevated temperatures were also studied. Cutting forces at the tool/workpiece interface have been measured in-situ. Temperatures on the surface of cutting tools were evaluated. The features of friction and wear behavior as well as mechanisms of tribo-adaptation of TiAlCrN/NbN nano-multilayered coatings were outlined.

New-onset diabetes after renal transplantation (NODAT) is known to be a potent risk factor for cardiovascular events. We therefore investigated the incidence and risk factors for NODAT, and evaluated surrogate endpoints of atherosclerosis in Japanese patients with stable renal function after renal transplantation. Seventy-nine patients were enrolled in the study, and a 75 g oral glucose tolerance test (OGTT) was performed in subjects excluding patients with known NODAT. We evaluated the risk factors for NODAT and the degree of atherosclerosis, determined by brachial-ankle pulse wave velocity (baPWV), ankle-brachial blood pressure index (ABPI) and intima-media thickness (IMT) of the carotid artery. Eleven patients diagnosed as NODAT had significantly higher fasting plasma glucose before transplantation, blood pressure, and incidence of hepatitis C virus (HCV) infection than patients without NODAT. Multivariate regression analysis revealed that the independent determinant of NODAT was fasting plasma glucose pre-transplantation, HCV infection and systolic blood pressure. The baPWV in patients with NODAT was significantly higher compared to that in patients without NODAT. In addition, the independent determinant of baPWV evaluated by multivariate regression analysis was an increase in systolic blood pressure and age, and a decrease of adiponectin levels. In conclusion, we found that high fasting plasma glucose prior to transplantation, HCV infection and high blood pressure are risk factors for NODAT in Japanese patients after renal transplantation. Since NODAT patients have advanced arterial stiffness probably due to high blood pressure, strict control of blood pressure will be important for preventing the development of cardiovascular disease in NODAT.

The carbide and graphite formation and redistribution of alloy elements during solidification were investigated on Ni-hard type cast iron (Fe-C-Si-Ni-Cr-Mo) to develop higher quality rolls for hot steel strip mills. By the control of Ni and Si contents of iron, eutectic graphite flakes crystallize even in cast irons containing strong carbide formers such as V, Nb and Cr. The crystallization of Ni-hard type cast iron with V and Nb proceeds in the order of primary , + MC, + M3C and + graphite eutectic. Since the influence of each alloying element on graphite formation is estimated based on the solubility of C in molten iron, the change in graphite forming tendency of residual liquid is evaluated by the parameter expressing the solubility limit of C to molten iron. The amount of graphite increases with the decreasing of solubility parameter. In addition, inoculation with ferrosilicon effectively increases the graphite flakes.

The effects of water environment on tribological properties of DLC against stainless steel were studied for development of the hydraulic pumps, valves and cylinders based on metal. A ball-on-disk tribotester was developed for detailed examination of water environment, such as temperature (20–80 °C), dissolved oxygen (0.01–8 ppm), water pressure (0.1–20 MPa) and dissolved ions. DLC was deposited on the disk by the unbalanced magnetron spattering system. Pure water and quasi-tap water were used to study the effects of dissolved ions. The results showed that temperature and dissolved ions have a major impact on friction and wear of DLC. EPMA, XPS and AES indicated that tribofilm on the metal surface, which consists mainly of C, O and Fe, plays important role for the phenomena.

We compared the ventilatory and circulatory responses during 20 s of light dynamic leg and arm exercises performed separately using dominant and non-dominant limbs. Seventeen subjects performed a 20-s single-leg knee extension-flexion exercise with a load of 5% of maximal muscle strength attached to the ankle. Fifteen of the seventeen subjects also did a single-arm elbow flexion-extension exercise in which a load was attached to the wrist in the same way as in the leg exercise. Similar movements were passively performed on the subjects by experimenters to avoid the effects of central command. The magnitude of change from rest (gain) in minute ventilation during passive movement (PAS) was significantly smaller in the dominant limbs than in the non-dominant limbs, though a significant difference was not detected during voluntary exercise (VOL). In contrast, heart rate and blood pressure responses did not show any differences between the dominant and non-dominant limbs during either VOL or PAS. In conclusion, the initial ventilatory response to PAS in the dominant limbs was lower than that of the non-dominant limbs, though the ventilatory response to VOL was not. Circulatory responses were not different between the dominant and non-dominant limbs. These results suggest that peripheral neural reflex during exercise could be different between dominant and non-dominant limbs and that ventilatory response at the onset of exercise might be controlled by the dual neural modulation of central command and peripheral neural reflex, resulting in the same ventilatory response to both dominant and non-dominant limb exercise.

The present study investigated the effects of Hachimi-jio-gan (HJ) on diabetic hyperglycemia in streptozotocin (STZ)-induced diabetic rats. After STZ administration, rats had free access to pellets containing 1% HJ extract powder for four weeks. HJ markedly suppressed hyperglycemia in STZ-induced diabetic rats at three and four weeks after the start of administration. There were also significant increases in serum and pancreatic immunoreactive insulin levels in STZ and HJ co-administering rats. However, in the present study, the number of beta cells in the pancreatic Langerhans' islets did not increase. Next, in order to investigate the action mechanism besides the glycemic control action of insulin, the expression of glucose transporter 2 (GLUT2) protein, which is involved in glucose uptake and release in the liver, was investigated. GLUT2 protein expression was increased by STZ administration but was normalized after four weeks of HJ administration. Therefore, irrespective of the structural changes in pancreatic beta-cells due to STZ, HJ increased insulin production and secretion by the pancreas and significantly suppressed GLUT2 synthesis in the liver. Amylase secretion from the pancreas was measured to assess pancreatic secretion. Amylase activity was decreased by STZ but was increased by HJ. Therefore, the effects of HJ on STZ-induced hyperglycemia in rats could be summarized as follows: besides increasing insulin synthesis and release, HJ normalizes GLUT2 protein expression in the liver to suppress hyperglycemia. Hence, the results of the present study suggest for the first time that HJ affects not only the production and secretion of insulin, but also the release of glucose from the liver.

In electronic-type ferroelectrics, where dipole moments produced by the variations of electron configurations are aligned, the polarization is expected to be rapidly controlled by electric fields. Such a feature can be used for high-speed electric-switching and memory devices. Electronic-type ferroelectrics include charge degrees of freedom, so that they are sometimes conductive, complicating dielectric measurements. This makes difficult the exploration of electronic-type ferroelectrics and the understanding of their ferroelectric nature. Here, we show unambiguous evidence for electronic ferroelectricity in the charge-order (CO) phase of a prototypical ET-based molecular compound, α-(ET)2I3 (ET:bis(ethylenedithio)tetrathiafulvalene), using a terahertz pulse as an external electric field. Terahertz-pump second-harmonic-generation(SHG)-probe and optical-reflectivity-probe spectroscopy reveal that the ferroelectric polarization originates from intermolecular charge transfers and is inclined 27° from the horizontal CO stripe. These features are qualitatively reproduced by the density-functional-theory calculation. After sub-picosecond polarization modulation by terahertz fields, prominent oscillations appear in the reflectivity but not in the SHG-probe results, suggesting that the CO is coupled with molecular displacements, while the ferroelectricity is electronic in nature. The results presented here demonstrate that terahertz-pump optical-probe spectroscopy is a powerful tool not only for rapidly controlling polarizations, but also for clarifying the mechanisms of ferroelectricity.

Atomic-scale, tribo-ceramic films associated with dissipative structures formation are discovered under extreme frictional conditions which trigger self-organization. For the first time, we present an actual image of meta-stable protective tribo-ceramics within thicknesses of a few atomic layers. A mullite and sapphire structure predominates in these phases. They act as thermal barriers with an amazing energy soaking/dissipating capacity. Less protective tribo-films cannot sustain in these severe conditions and rapidly wear out. Therefore, a functional hierarchy is established. The created tribo-films act in synergy, striving to better adapt themselves to external stimuli. Under a highly complex structure and non-equilibrium state, the upcoming generation of adaptive surface engineered nano-multilayer materials behaves like intelligent systems - capable of generating, with unprecedented efficiency, the necessary tribo-films to endure an increasingly severe environment.

Mesoscopic thermoelectric heat engine is much anticipated as a device that allows us to utilize with high efficiency wasted heat inaccessible by conventional heat engines. However, the derivation of the heat current in this engine seems to be either not general or described too briefly, even inappropriate in some cases. In this paper, we give a clear-cut derivation of the heat current of the engine with suitable assumptions beyond the linear-response regime. It resolves the confusion in the definition of the heat current in the linear-response regime. After verifying that we can construct the same formalism as that of the cyclic engine, we find the following two interesting results within the Landauer-B\"uttiker formalism: the efficiency of the mesoscopic thermoelectric engine reaches the Carnot efficiency if and only if the transmission probability is finite at a specific energy and zero otherwise; the unitarity of the transmission probability guarantees the second law of thermodynamics, invalidating Benenti et al.'s argument in the linear-response regime that one could obtain a finite power with the Carnot efficiency under a broken time-reversal symmetry. These results demonstrate how quantum mechanics constraints thermodynamics., Comment: 8 pages, 3 figures, close to publish version

Application of quaternary nitride (Ti,Cr,Al) N/WN nano-multilayered coatings results in a significant increase of tool life as well as wear behavior improvement under conditions of dry high-speed machining (end milling) of hardened H13 steel (HRC 50). Investigations of surface structure characteristics of TiAlCrN/WN coatings using TEM, SEM, EDX, and XPS have been performed. The microhardness, modulus of elasticity, coefficient of friction and the oxidation stability of the coatings were also studied. Cutting forces at the tool/workpiece interface have been measured in situ. It was shown that the major cause of the cutting tool life and wear behavior improvement is the enhanced tribological adaptability of a TiAlCrN/WN coating. By means of adding W to the composition of TiAlCrN/WN nano-multilayered coatings, W–O tribo-films form in synergy to alumina and provide tool life improvement.

The transcription factor pancreatic and duodenal homeobox factor 1 (PDX-1) is expressed in pancreatic progenitor cells. In exocrine pancreas, PDX-1 is down-regulated during late development, while re-up-regulation of PDX-1 has been reported in pancreatic cancer and pancreatitis. To determine whether sustained expression of PDX-1 could affect pancreas development, PDX-1 was constitutively expressed in all pancreatic lineages by transgenic approaches. The transgenic pancreas was markedly small with the replacement of acinar cells by duct-like structures, accompanied by activated Stat3. Genetic ablation of Stat3 in the transgenic pancreas profoundly suppressed the metaplastic phenotype. These results provide a mechanism of pancreatic metaplasia by which persistent PDX-1 expression cell-autonomously induces acinar-to-ductal transition through Stat3 activation.

TixCryAlzN (x + y + z = 1) films were synthesized by the arc ion plating method (AIP) under various deposition temperatures between 400 and 650 °C. The films, synthesized from Ti0.1Cr0.2Al0.7 and Ti0.25Cr0.1Al0.65 targets, were identified as a cubic type structure below 580 and 650 °C, respectively, over which the films were a mixture phase of cubic and hexagonal type. The microhardness of these films decreased from 30 GPa to 24 GPa corresponding with the phase transition from the cubic to the mixture phase. The grains size of c-Ti0.1Cr0.2Al0.7N and c-Ti0.25Cr0.1Al0.65N films were approximately 100 nm and changed to 20–30 nm after the phase transitions. The effect of post-annealing on the phase transition was investigated for the films with the cubic structure. The result showed that the cubic-type films partially transformed to hexagonal structure by annealing over 900 °C, which led to increase in lattice parameter. In this paper, mechanical properties, microstructure and thermal stability of TixCryAlzN films as a function of Cr contents were investigated and discussed on phase transitions.

The purpose of this study was to investigate the effect of the duration of hyperglycemia on the osseointegration and bone formation around titanium implants. Rats were divided in to three groups, the short-term-hyperglycemia group (group S), the long-term-hyperglycemia group (group L), and the control group. In groups S and L, hyperglycemia was induced with streptozotocin 2 and 6 weeks before implantation, respectively. Rats received titanium implants in their femora, and were sacrificed 1, 2, 4, and 8 weeks after implantation. In the control group, the newly formed bone that directly contacted the implant surface increased with time. In groups S and L, fibrous connective tissue was observed on some parts of the implants. There were significant differences in bone-implant contact among the three groups at 4 weeks after implantation. Newly formed bone including the bone fragments scattered by surgery was remodeled, becoming thinner with time in the control group, whereas it remained immature, away from the implant in groups S and L. Although there were significant differences in the number of TRAP-positive cells between the control group and the hyperglycemia groups, there was no significant difference between groups S and L. It is suggested that the duration of hyperglycemia affected osseointegration around titanium implants.

Dynamical localization, i.e., reduction of the intersite electronic transfer integral t by an alternating electric field, E(omega) , is a promising strategy for controlling strongly correlated systems with a competing energy balance between t and the Coulomb repulsion energy. Here we describe a charge localization induced by the 9.3 MV/cm instantaneous electric field of a 1.5 cycle (7 fs) infrared pulse in an organic conductor alpha-(bis[ethylenedithio]-tetrathiafulvelene)_2I_3. A large reflectivity change of > 25% and a coherent charge oscillation along the time axis reflect the opening of the charge ordering gap in the metallic phase. This optical freezing of charges, which is the reverse of the photoinduced melting of electronic orders, is attributed to the 10% reduction of t driven by the strong, high-frequency (omega>t/h_bar) electric field., 20 pages, 6 figure