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We report on the first demonstrated near-complete coverage of the S-, C-, and L-bands using six different ranges of wavelength-selectable microarray light sources (WSLs) based on a distributed-feedback (DFB) laser diode (LD) array. The six devices were fabricated on only two wafers. Each device has a tuning range of more than 15 nm, a sidemode suppression ratio of over 40 dB, and a fiber-coupled power greater than around 10 mW.

A wide-band wavelength-selectable light source module having an integrated multiwavelength locker has been developed. An eight-distributed-feedback (DFB) arrayed monolithic light source was designed to have 40-nm tunable range in the L-band by covering 5 nm per DFB laser diode. A uniquely designed etalon-based wavelength locker achieved very stable operation and uniform locking performance for all channels. Wavelength variation in the short term at room temperature was much less than 1 pm and the locked wavelength stayed within +/-5 pm when the case temperature of the module was varied from -20/spl deg/C to 65/spl deg/C.

Widely spread renewable energies (REs) will destabilize electricity supply-demand balancing because of their uncontrollability and unpredictability. Therefore effective balancing technology is required. We focus on distributed energy storages (ESs) and propose a novel balancing technology using distributed ESs, “Virtual Integration (VI) of distributed ESs”. VI enables us to control multiple ESs as a concentrated single ES: VI can make ESs respond quicker, control electric-charge/discharge of ESs precisely, and achieve reliable property of ESs. The feature of VI is that by regarding the difference in dynamic status of each ES as a functional characteristic of ES, a virtually integrated ES is built to create new functions by arranging functional characteristics appropriately. In other words, VI technology properly assigns real-time charging/discharging power to each ES on the basis of each characteristic. For an example of reliable control of ESs, we numerically demonstrated VI suppresses capacity degradation of lithium Ion batteries by 20%.

Recently, nanocomposite materials have attracted much attention in electrical treeing. In this study, we carried out a three-dimensional (3D) tree simulation using two macrosized fillers (i.e., spherical and discoid) as the first step in considering simulated trees in nanocomposite materials. Moreover, we carried out a comparison of simulated tree shapes depending on filler type. The results indicate that the simulated tree propagates more easily in composite insulating materials with spherical fillers than in those with discoid fillers from the viewpoint of the barrier effect.

The effects of phosphorus doping on the structural and superconducting phase transitions of BaNi2(As(1-x)P(x))2 were studied. The specific heat, resistivity, and magnetic susceptibility were measured. The results revealed an abrupt increase in the superconducting transition temperature (T(c)) from 0.6 K in the triclinic phase (space group P1¯) with less phosphorus (x≤0.067) to 3.3 K in the tetragonal phase (space group I4/mmm) with more phosphorus (x≥0.067). Our data analysis suggests that a doping-induced softening related to an in-plane Ni and As(P) phonon mode is responsible for the enhanced superconductivity in the tetragonal phase.

With the use of a numerical method by linearizing the nonlinearities caused by an amplifier-analyzer system, we can reproduce a pulse height spectrum reflecting the actual characteristics of a radiation detector itself. This method was applied to spectrometer systems of a 3He proportional counter for fast neutron measurements and a high-purity Ge detector for gamma-ray measurements. As the pulse height spectrum distortion due to the nonlinearities of the measuring system was improved especially in the lower pulse height region, we can discuss the precise pulse height relations and the intrinsic nonlinearities caused in radiation detectors.

Relative gas multiplication along the cylindrical axis of a /sup 3/He proportional counter was measured by using a collimated beam of thermal neutrons produced in a graphite pile. The gas multiplication changed gradually in the vicinity of both edges of the sensitive region. The total transition region of the gas multiplication was found to correspond to 23% of the nominal sensitive region. Response functions for thermal neutrons and 2.413 MeV neutrons were calculated with consideration of the measured edge effect by a modified NRESP Monte Carlo code. In both cases, the results showed good agreement with the measured pulse height distributions. >

The cavity length dependence of the linewidth property of complex coupled (CC) DFB lasers is investigated. In CC-DFB lasers with a fixed geometrical structure of the active region, the cavity length strongly affects the ratio of index coupling strength to the gain coupling one, which results in the variation of the effective linewidth enhancement factor /spl alpha//sub eff/. It is also found that pure gain coupled (GC) DFB lasers have the saturation characteristic in the linewidth power product, with the extension of the cavity length, These results indicate the importance of the selection of the cavity length in CC-DFB lasers. >

With an aim toward a high-saturation power operation, a tapered-waveguide traveling-wave semiconductor laser amplifier (SLA) with a Ga/sub 0.68/In/sub 0.32/As/GaInAsP/InP tensile-strained quantum-well (QW) structure was investigated and realized for the first time. In spite of the high differential gain in the tensile-strained QW active layer, a high-saturation-output power of 18.5 dB (1 mW) (71 mW) and a high-maximum-output power of 20.4 dB(1 mW) (110 mW) were obtained with a narrow single-lobed beam-divergence property. These results indicate that the saturation performances of SLA's with tensile-strained active layers can be improved by the tapered-waveguide structures. >

Summary This paper describes an investigation of hard surfacing of aluminium alloy by conventional pulsed and low‐frequency pulsed MIG welding using a newly developed seamless cladding wire (copper sheath with solid aluminium wire as the inside core) of 1.6 mm diameter. Two cladding wires with different copper contents (34mass%Cu and 52mass%Cu) were tested. The effect of the shielding gas on the hardening characteristics and blowhole generation was also investigated. A Vickers hardness of Hv160–280 is obtained, being some 2–3 times greater than that of the base metal. Micro‐blowholes not detected by radiographic inspection mostly occur in the weld metal, tending to decrease with an increasing mixing ratio of helium gas.

In this letter, we have simultaneously fabricated five wavelength-selectable microarray light sources (WSLs), each having a different wavelength range integrated with an electroabsorption (EA) modulator on a single wafer. We also introduced a novel device configuration scheme for wavelength-independent modulation. The five EA-WSLs fully covered the entire C-band and had a low uniform threshold current of 6 /spl plusmn/ 1 mA at 25/spl deg/C. Wavelength-independent extinction characteristics were obtained over a tuning wavelength range of 8 nm, and 2.5-Gb/s transmission over 600 km was successfully achieved.

Background In April 2009, Pandemic (H1N1) 2009 has reported from Mexico and has spread so rapidly in the worldwide. However, the number of dead cases caused by this infection has a big difference among the counties and regions. We describe the considerable reasons why first Nations people have experienced such high rate of severe conditions from the socioeconomic point of view which are related to healthcare.

Human nasal mucosal samples exposed in vitro to substance P or allergenic Ag were tested for the mRNA of IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, TNF-alpha, and IFN-gamma using specific reverse transcriptase-polymerase chain reaction assays. After the administration of substance P, at dosages ranging from 10(-6) to 10(-9) M, an enhanced expression of the mRNA for IL-1 beta, -3, -5, -6, TNF-alpha, and IFN-gamma was observed in all mucosal samples of allergic subjects and in half of the nonallergic subjects. The expression of IL-2 and IL-4 was low. Mucosal samples of allergic subjects showed an increased expression of mRNA for cytokines after administration of specific Ag, whereas no enhancement was observed in samples from nonallergic subjects. Our data suggest that substance P may regulate allergic reactions via enhanced production of certain regulatory cytokines.

Fairly low threshold current operation was achieved with Ga/sub 0.66/In/sub 0.34/As/GaInAsP/InP tensile-strained (TS) single-quantum-well (SQW) lasers with 30- approximately 40-nm-wide and 70-nm-period wire active region fabricated by a combination of a wet chemical etching and two-step OMVPE (organometallic vapor phase epitaxy) growth. Threshold current as low as 16 mA and threshold current density of 816 A/cm/sup 2/ were obtained under a room temperature CW condition. In comparing the spontaneous emission peak wavelength of the TS-SQW wire laser with that of the TS-SQW film laser, an approximately 10-meV blue shift of the fundamental energy level was observed in the TS-SQW wire laser. >

Improvements in the fabrication of GaInAs(P)/InP devices consisting of an ultrafine structure by using two-step organometallic vapor phase epitaxy (OMVPE) growth, electron beam exposure direct writing, and wet chemical etching are reported. This improved process achieved, for the first time, a room-temperature continuous-wave (CW) operation of GaInAs/InP quantum-wire lasers consisting of 5-nm-thick and 10-30-nm-wide vertically stacked triple quantum-wire active region within the period of 70 nm. A large blue shift of approximately 40 nm was observed in both the lasing and the electroluminescence spectra of Ga/sub 0.3/In/sub 0.7/As/InP compressively strained multi-quantum-well (MQW) wire lasers consisting of a 3-nm-thick and 30-60-nm-wide five-wire active region, which suggests a reduced effective mass of holes along the in-plane direction. >

Photoelectric properties of evapolated metal-free phthalocyanine (H2Pc) and lead phthalocyanine (PbPc) films were investigated in the sandwich type cells using three kinds of metal electrodes (Au, Al, Pb). Current-voltage (I-V) characteristics and short circuit photo current (Isc) spectra strongly depended on metal electrodes. It is indicated that a charge separation of photo generated carriers occurred at the interface between H2Pc and PbPc from Isc spectra of double layered (H2Pc/PbPc and PbPc/H2Pc) cells.

Doping effect of organic molecules in merocyanine evaporated films are investigated. As organic dopant, tetracy-anoquinodimethane and tetrathiafulvaiene were employed and the merocyanine films containing organic dopant were fabricated by using a co-evaporation technique. The electrical properties of Al/MC/Ag Schottky cell were examined by current-voltage, thermally stimulated current and capacitance-temperature measurement. Forward current in TCNQ-doped-MC sample was increased with increasing concentration of TCNQ. On the contrary, forward current in TTF-doped-MC sample was decreased with increasing TTF concentration.

A design theory is presented to apply inductively coupled superconducting striplines to microwave filters, in which the coupled stripline system is considered as four-port circuitry. By obtaining eigenvalues for impedance, admittance, and scattering matrices, the authors obtained general formulas for designing bandpass filters. The microwave filters using this coupling scheme are simple in design and have advantages of external-modulation capability. Experiments to demonstrate the validity of this coupling scheme have been performed in the frequency range between DC and 300 GHz by investigating the coupling between a Josephson oscillator and an external stripline. >

After achieving a reasonable success in BD-100R neutron-bubble detectors, the Bubble Technology Industries (Canada) has recently developed a new type of γ-bubble detector and is commercially available. A series of experiments were carried out to determine the sensitivity and the effect of temperature on both of the above mentioned detectors. The response of these detectors is found to be strongly dependent upon the temperature during irradiation. The γ-bubble detector needs a lot of improvements before it can be used in actual measurements. Although BD-100R detector has a lot of promising properties, it cannot replace CR-39 based personnel neutron dosimeters, but they complement each other.

In Part-I of this paper, computer calculations for determining the calibration factors of CR-39 based neutron dosimeters were described. Here in Part-II, related experimental work is presented. Rem counters, bubble detectors and different types CR-39 based neutron dosimeter were irradiated in free air and on a water phantom with known fluences of monoenergetic neutrons. Irradiations were also performed in a D2O moderated 252Cf neutron field. From the observed readings (number of bubbles or counts or track/cm2 or ECE spots/cm2), calibration factors were determined.

Measurements concerning radon and its daughter products' concentration levels have been performed in 42 selective houses of the Tsukuba Science City (Japan) using CR-39 and LR-115 nuclear track detectors. These included both single story houses and flats in multi-storied buildings. Four CR-39 and four LR-115 detectors were put into a zippable polyethylene bag and a number of such bags were prepared. These detector loaded bags were then installed in two bedrooms of each of the houses/flats and were exposed for a period of three months during the winter season (i.e. from December to February). These radon exposed samples were then processed, analyzed and related to the Bq/m 3 . These studies indicated that the radon levels are very low in the houses surveyed and do not pose any serious threat to the occupants.

We developed high-performance distributed feedback array-based wavelength-selectable light sources (WSLs), covering the entire C-band with five simultaneously fabricated devices. We fabricated five different range WSLs on a wafer, each with a unique 8-nm tuning range to cover 40 100-GHz-spaced channels. Uniform characteristics, such as an Ith of 8.3/spl plusmn/1.2 mA, a sidemode suppression ratio of over 45 dB, and a fiber-coupled power greater than 8.5 mW were obtained.

Water tree propagation depends on temperature. However, water tree propagation in a wide temperature range remains to be elucidated. In this study, we investigated the temperature characteristics of water tree propagation from (−20°C to 80°C in cross-linked polyethylene (XLPE) sheets. The water tree observed has a radial structure with a fanlike or human-hand-like shape at low temperatures (−20°C∼room temperature), but a dense-ball-like or sphere shape at high temperatures (50°C ∼ 80 °C). On the basis of the results of our microscopy observation of a water tree, we considered water tree propagation in two temperature ranges: low temperatures and high temperatures. Furthermore, for the growth mechanism of water trees, we suggested that an electromechanical factor is dominant at low temperatures, whereas an electrochemical factor in addition to an electromechanical factor is dominant at high temperatures.

A 10-Gb/s Mach-Zehnder modulator is monolithically integrated with a tunable laser source based on a 2-ring loop-filter with a small device dimension (2.5 × 0.9 mm2). Sufficient static extinction ratio of 16.5 dB was obtained both at 1573.92 and 1595.50 nm.

Recently, the Bubble Technology Industries has developed a new type of γ-bubble detector for measurement of γ doses and have made it commercially available. A series of experiments were carried out at the Electrotechnical Laboratory (ETL) and Centre for Nuclear Studies (CNS) to determine the sensitivity of the detector, effect of temperature and recompression time on the sensitivity and to find out whether such detectors can be used for the measurement of the γ-rays that are always associated with neutron fields. The sensitivity of the detector is found to be about 15 bubbles/μSv at 21.8°C. The response of the detector is strongly dependent upon the temperature during irradiation. In the light of our results, this detector needs many improvements before it can be used for accurate measurements of γ doses in routine dosimetry.

A room temperature CW operation of Ga/sub 0.3/In/sub 0.7/As/GaInAsP/InP GRINSCH compressive strained MQW lasers with 30 approximately 60 nm wide wire active region was achieved. This device was fabricated by two-step LP-OMVPE growths on p-type InP substrate and wet chemical etching. Threshold current as low as 53 mA (L=910 mu m, J/sub th/=2.9 kA/cm/sup 2/) was obtained at RT-CW condition. The spontaneous emission peak and the lasing wavelength of strained MQW wire lasers exhibited approximately 20-meV blue shift from those of MQW film lasers cut out from the same wafer. >

The effective linewidth enhancement factor alpha /sub eff/ of DFB lasers which have both gain and index coupling coefficients is theoretically analyzed. The unique reduction mechanism of alpha /sub eff/ due to the optical negative feedback of modal phase and modal gain in gain coupled DFB lasers was found for the first time. The numerical result showed that alpha /sub eff/ can be reduced to almost one half of the material defined linewidth enhancement factor alpha when there exists an index coupling coefficient comparable to the gain coupling coefficient. >

An unusual case of coexisting acromegaly and Cushing's syndrome is reported in a 34-yr-old female. There was no biochemical or morphological evidence to suggest the presence of other endocrinopathies. She did not have any family history to suggest a hereditary tendency to endocrine disorders. Her acromegaly and Cushing's syndrome were proven to be due to a pituitary somatotroph adenoma and a cortisol-producing adenoma in the right adrenocortex, respectively. Surgical removal of both tumors led to a marked biochemical improvement of the two endocrinopathies. To account for the simultaneous occurrence of the two endocrine tumors, at least two endocrine syndromes may be considered. One of them is Carney's complex. However, Cushing's syndrome in this complex is unexceptionally due to primary pigmented nodular adrenocortical disease, differing from the adrenal pathology of our patient. In addition, a lack in this case of any other characteristic suggestive of this syndrome appears to speak against this possibility. A second possibility is multiple endocrine neoplasia type 1. The absence of a parathyroid or pancreatic islet cell tumor does not strongly support this possibility, but adrenocortical lesions are not rare in this syndrome although they are only rarely functional. However, existence of similar case reports, although very few, in the literature leaves the possibility that she represents another rare variant of sporadic multiple endocrine neoplasia type I syndrome.

The multicluster dynamic model of light nuclei, studied and verified earlier as applied to 6Li nucleus is used together with the folding model to find the interaction potentials in the X+6Li systems (X=n, p, 3He, 3He, 4He). The calculations of the real parts of the potentials are self-consistent and, in contrast to the previous RGM calculations of the same systems, do not include any free parameters. A good agreement between theoretical predictions and the respective experimental data on elastic scattering of the A

We developed compact (1.136 mm/sup 2/) eight-channel wavelength-selectable microarray distributed feedback laser diodes (DFB-LD's) with a monolithically integrated 8/spl times/1 multimode-interference (MMI) optical combiner, a semiconductor optical amplifier (SOA), and an electro-absorption (EA) modulator. By using /spl plusmn/10/spl deg/C thermal tuning, an addressable wavelength range of 15.3 nm with uniform device characteristics and 2.5-Gb/s modulation performance were successfully demonstrated.

We carried out a three-dimensional tree simulation of a composite system with an interface perpendicular or parallel to the electric force line based on a dielectric breakdown model (DBM) considering the growth probability. It was found that an interface perpendicular to the electric force line exhibits a positive barrier effect and that an interface parallel to the electric force line exhibits a negative barrier effect.

The fluid-attenuated inversion recovery imaging sequence is a widely used MRI sequence of the brain. It is an inversion recovery pulse sequence, designed to suppress signals from the cerebrospinal fluid. It is highly sensitive for detection of lesions adjacent to or within the cerebrospinal fluid, associated with T(2) prolongation or T(1) shortening. The term "hyperintense cerebrospinal fluid" is used to describe failed suppression or hyperintensity of cerebrospinal fluid on fluid-attenuated inversion recovery imaging of the brain. It is often encountered in many important pathological conditions, including subarachnoid haemorrhage, meningitis and leptomeningeal metastasis. However, certain non-pathological states in which there is no definite cerebrospinal fluid abnormality can also present with hyperintense cerebrospinal fluid. Correct interpretation of abnormalities is important to arrive at an appropriate diagnosis. This pictorial review provides fluid-attenuated inversion recovery images of hyperintense cerebrospinal fluid of the brain and describes distinguishing features, focusing on non-pathological conditions.

We propose a convolution model which yields the probability distribution of multiplicity in hadron-nucleus collisions as a result of convolution of the multiplicity distribution of hadron-nucleon collisions. It is predicted that as the collision number increases, these multiplicity distributions approach the same functional form.

In order to realize efficient coupling between a flux-flow type Josephson oscillator (FFO) and an external stripline, the authors carried out experiments to investigate the inductive coupling scheme in a strong coupling regime. By adopting NbN films with large penetration depths as electrodes for strong coupling, they were able to realize coupling sections with a coupling coefficient alpha =M/ square root L/sub 1/L/sub 2/ as large as 0.7, with M, L/sub 1/, and L/sub 2/ being mutual inductance, self-inductances of, the FFO, and the stripline, respectively. Using this design for the coupling, the authors succeeded in detecting AC fields at frequencies around 150 GHz, which were emitted from FFO to the stripline via the coupling section.

The properties and applications of the inductive coupling of a superconducting stripline system, which takes advantage of kinetic inductance of thin superconducting films, are studied. The system, composed of two striplines inductively coupled through a common electrode as a four-port circuit, was formulated by obtaining its scattering coefficients in a general form. The system is characterized with the coupled-mode theory. Based on the analysis, it is proposed that a novel type of kinetic inductance devices for microwave analog components, such as directional couplers, microwave switches, variable filters, and efficient coupling elements for striplines. Experiments on stripline coupling with this scheme are also discussed.

The response of our previously reported cubical fast neutron dosimeter is studied in terms of 10 mm directional dose equivalent, H'(10), both in free air and on a tissue phantom. Its response has been extended to thermal neutrons by introducing a 0.045 μm thick layer of LiF converter between the detector and radiator stack (i.e. 150 μm polyimide + 800 μm polystyrene + 3 μm polyethylene). Our studies predict that the above radiator-detector assembly would yield a flat response over the neutron energy range of thermal to 15 MeV (within 26% variation) on a tissue phantom. A cubical dosimeter based on the above radiator-detector assembly (only one part of the assembly containing a 0.045 μm thick layer of LiF) would yield an angular response reasonably close to that required (i.e. H'(10)) over a wide neutron energy range.

An experiment was carried out to measure the radon and its airborne daughter product levels in the bed rooms of 40 houses. The houses chosen for this experiment were constructed from same building material and the bed rooms chosen were approximately of similar dimensions. The main objective of this experiment was to study the living standards (e.g. ventilation of the houses) of the residents from the measured values of radon and its daughter product concentration levels. Our results indicate that, except for a few cases, one can predict the living habits of the occupants from the measured values of radon and its daughter concentration levels.

We have performed an ultrahigh-resolution angle-resolved photoemission spectroscopy study of slightly overdoped (Bi,Pb)2Sr2CuO6 to elucidate the origin of the pseudogap. By using a newly developed xenon-plasma light source, we determined the comprehensive momentum and temperature dependencies of the superconducting gap and the pseudogap. We found that the antinodal pseudogap persists far above the superconducting transition temperature and is smoothly connected to the nodal gap. The characteristic temperature of the pseudogap scales well with the superconducting gap size irrespective of the momentum location. The present experimental results point to the pairing origin of the pseudogap.

We carried out three-dimensional tree simulation in the presence of a barrier and an air layer between a needle electrode and a plane electrode based on a dielectric breakdown model (DBM) considering growth probability. It was found that a three-layer model is similar to a two-layer model. However, the three-layer model can simulate more accurately than the two-layer model in detail. In the three-layer model, the simulated tree tends to propagate while creeping on or developing along the barrier. Therefore, it is suggested that the three-dimensional tree simulation of the three-layer model is valid for simulating composite insulating systems with a barrier and an air layer.

A monolithically integrated wavelength-tunable laser diode based on a novel loop-filter that consists of two ring resonators and an asymmetric Mach-Zehnder Interferometer (AMZI) is demonstrated with 39-nm tuning range over 30-dB SMSR.

A compact 10 Gb/s full C-band tunable transmitter module of external cavity tunable light source with monolithically integrated Mach-Zehnder modulator was developed. Penalty free 10 Gb/s - 80 km transmission over full C-band has been successively achieved.