Fracture and deformation properties of Ni-Fe superalloy in cryogenic high magnetic field environments

The present paper includes experimental and analytical data on the fracture properties of a nickel-iron superalloy, a ferromagnetic austenite, at 4 K in magnetic fields of 0 and 6 T. The tensile, notch tensile and small punch tests are employed. A finite element analysis is also performed to convert the experimentally measured load-displacement data into useful engineering information. To interpret the results we review the available theory of the influence of magnetic field on the stress intensity factor for a crack in ferromagnetic materials.     

Prevention of neutrophil apoptosis by monosodium urate crystals

The effects of monosodium urate (MSU) crystals on apoptosis of cultured peripheral blood neutrophils were investigated. MSU crystals at low concentrations decreased the rate of spontaneous apoptosis of neutrophils in a dose- and time-dependent manner. The culture supernatant of MSU crystal stimulated neutrophils also promoted a delay in neutrophil apoptosis. MSU crystals at higher concentrations rapidly caused cell lysis. These findings indicated that MSU crystals are capable of amplifying the inflammatory responses of gouty arthritis by decreasing the rates of neutrophil apoptosis at lower concentrations and inducing cell lysis at higher concentrations.     

A CMOS integrated circuit for multichannel multiple-subjectbiotelemetry using bidirectional optical transmissions [weightlessnessin space effects application]

A CMOS integrated circuit for a noninvasive biological-signal telemetry system specified for use in medical and physiological studies of the influence of weightlessness in space is presented. The system can monitor multichannel (4 channels maximum) biological signals from multiple subjects (4 subjects maximum) in real time by using time multiplexing. A key technique so-called synchronized multiple-subject telemetry, to achieve multiple-subject telemetry has been proposed. This technique utilizes bidirectional optical transmissions with direct and scattered infrared lights between an observer and each of the subjects. An experimental CMOS IC to give a small light-weight low-power, and smart telemetry instrument for use on animals has been developed. This IC is for evaluating circuit blocks of the implantable monolithic telemetry instrument. The major circuit blocks include CMOS digital circuits for synchronization, subject selection and time multiplexing, analog circuits for pulse interval modulation, and other blocks such as a CMOS optical pulse receiver and an LED driver. A preliminary experimental multichannel telemetry from two subjects has been performed with the implemented IC chips, and the principal operation of the multiple-subject optical biotelemetry has been demonstrated     

The temperature dependence of luminescence from a long-lasting phosphor exposed to ionizing radiation

The temperature dependence of luminescence from a long-lasting phosphor (LLP), SrAl₂O₄ : Eu²⁺,Dy³⁺, exposed to ionizing radiation has been measured to understand the LLP luminescence mechanism. Evaluation of the decay constants of the LLP exposed to -, β- or γ-rays at temperatures from 200 to 390 K showed that the decay constant is divided into four components ranging from 10⁻⁴ to 10⁻¹ s⁻¹ with activation energies of 0.02–0.35 eV.

Total luminous intensity from the LLP with changing irradiation temperature has its maximum value around the room temperature. Irradiation at elevated temperature (390 K) has the total luminescence pattern with monotonous decrease as temperature rises. As a result of evaluating the temperature dependence of luminescence, the luminescence mechanism is considered as follows:

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Light scattering studies on crystallization in polyethylene terephthalate

The light scattering from the spherulites of polyethylene terephthalate grown near the glass transition temperature has been investigated. The Hv scattering profiles can be reproduced by the sum of the ideal spherulite scattering with the distribution of spherulite radius and the isotropic scattering from randomly oriented crystallites. The ratio of optical anisotropies in the isotropic scattering to the ideal spherulite scattering is obtained by the method established to eliminate the effects of the number density of spherulites and the coefficient depending on the experimental conditions. It is found that the anisotropy ratio is almost independent of the crystallization time and of temperature above 106 °C, while it is larger at a crystallization temperature of 103 °C. The spherulitic structure is discussed in terms of the anisotropy ratio.     

A self-aligned gate GaAs MESFET with p-pocket layers forhigh-efficiency linear power amplifiers

This paper describes a newly developed GaAs metal semiconductor field-effect transistor (MESFET)-termed p-pocket MESFET-for use as a linear power amplifier in personal handy-phone systems. Conventional buried p-layer technology, the primary technology for microwave GaAs power MESFET's, has a drawback of low power efficiency for linear power applications. The low power efficiency of the buried p-layer MESFET is ascribed to the I-V kink which is caused by holes collected in the buried p-layer under the channel. In order to overcome this problem, we have developed the self-aligned gate p-pocket MESFET which incorporates p-layers not under the channel but under the source and drain regions. This new MESFET exhibited high transconductance and uniform threshold voltage. The problematic I-V kink was successfully removed and an improved power efficiency of 48% was achieved under bias conditions, which resulted in adjacent channel leakage power at 600-kHz offset as low as -59 dBc for 1.9-GHz π/4-shift QPSK modulated input     

Intracoronary infusion of E6010 has more potent thrombolytic activity than tissue plasminogen activator (t-PA) in dogs: a higher plasma level of E6010 than t-PA causes potent thrombolytic activity

We examined the thrombolytic properties of a novel modified human tissue plasminogen activator (PA) (E6010), in which cysteine 84 is replaced by serine, and which has a prolonged biologic half-life (t1/2). We compared the thrombolytic efficacy of continuous intracoronary (i.c.) infusion of E6010 with that of recombinant human tissue PA (rt-PA) in a canine model with copper coil-induced 1-h-old coronary artery thrombi and also compared the relation between thrombolytic efficacy and plasma clearance represented by pharmacokinetic parameters of i.c.-infused E6010 and rt-PA. Sixty-minute E6010 and rt-PA i.c. infusions were compared. The thrombolytic effects of i.c.-infused E6010 and rt-PA, represented by time to reperfusion (TR), reperfusion rate at 60 min (RR), and reocclusion rates at 60 min after reperfusion (OR) were as follows. E6010: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 25 +/- 10, 15 +/- 10, 13 +/- 5 (min); RR 100, 100, 100 (%); and OR 0, 0, 17 (%), respectively. Recombinant t-PA: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 47 +/- 12, 18 +/- 17, 14 +/- 4 (min); RR 50, 75, 100 (%); and OR 100, 33, 33 (%), respectively. These findings indicate that E6010 has more potent thrombolytic activity than rt-PA.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cognitive model of team cooperation in en-route air traffic control

Since controller teams are in charge of en-route air traffic control, team cooperation is a key issue for good control performance. We conducted ethnographic field observation at the Tokyo Area Control Center and then analyzed the obtained data to develop a cognitive model of team cooperation in en-route air traffic control. We segmented conversational records, behavioral records, and so on by control unit, and then clarified relations between the segments and identified expert knowledge and judgment behind them. Cognitive processes of controller teams were reconstructed based on a concept of distributed cognition. The analysis revealed that the mutual belief model is applicable to team cooperation processes, the role assignment of tasks within a controller team is implicit and that control plans are implemented smoothly once team situation awareness has been established. A cognitive model of controllers?? team cooperation has been constructed based on these findings.     

Solid-liquid phase equilibria of benzene + 2-methyl-2-propanol system under high pressures

Solid-liquid phase equilibria of the benzene + 2-methyl-2-propanol system have been investigated at temperatures from 278 to 323 K and pressures up to 300 MPa using a high-pressure optical vessel. The uncertainties of the measurements of temperature, pressure and composition are within ±0.1 K, ±0.5 MPa, and ±0.001 mole fraction, respectively. The freezing pressure at a constant composition increases monotonously with pressure. The eutectic point shifts to a higher temperature and benzene-rich composition with increasing pressure. In order to describe the pressure-temperature-composition relation of high-pressure solid-liquid phase equilibria, a new simple equation has been proposed as follows: