Monolithic rat-race mixers for millimeter waves

In this paper, we report on fully monolithic millimeter-wave Schottky-barrier diode (SBD) down-converters with an IF amplifier using heterojunction bipolar transistors (HBT's). A rat-race circuit is used for the mixer, and is analyzed using a harmonic-balance simulator. The measured conversion gain and the isolation are 7.1 and 29 dB in the V-band design, and 8.0 and 25 dB in the W-band design, respectively. The conversion gains are matched well with the circuit simulation     

Comparison of the effect of a proteolytic enzyme dispase and a chelator for the preparation of epidermal sheet from nude mice.

Histochemical studies of epidermal Langerhans cells require well-preserved epidermal sheets. We studied the conditions for the preparation of the epidermal sheets from the skin of the ear, hind limb and trunk of nude mice. Two types of commercial dispase, and ethylenediaminetetraacetic acid (EDTA), were used at several concentrations and the effects were compared. Dermo-epidermal separation was evaluated by the preservation of ATPase activity of Langerhans cells in the epidermal sheet and by the ultrastructure of epidermal cells (Langerhans cells and keratinocytes) as well as epidermal-dermal junction. Good separation depended on the combination of the concentration of the reagent and site of the skin. The concentrations of both dispase and EDTA effective for separation of the epidermis in the nude mouse were lower than those in other mouse strains reported.     

In vivo effect of growth-inhibitor produced by Pseudomonas aeruginosa isolates and anti-pseudomonal drugs on model infection due to Pseudomonas aeruginosa

Pseudomonas aeruginosa Nos. 1 and 5, each co-existing growth-inhibitor-producing and -nonproducing cells, were used in this study. An equal number of both cells (each 10(8) CFU/mouse) was challenged intraperitoneally to mice, and these cells in the heart blood and kidneys of mice were determined. Furthermore, the effect of piperacillin, ceftazidime and sisomicin on the cell distribution in mice was studied in the model infection due to P. aeruginosa Nos. 1 and 5. As a control experiment both cells of P. aeruginosa No. 1 were each challenged intraperitoneally at a dose of 10(8) CFU/mouse to mice of two groups, but there were no marked differences between the two types in cell counts of the heart blood or kidneys 9 hours after challenge. When a concomitant challenge of both cells (each 10(8) CFU/mouse) was performed in mice, the number of growth-inhibitor-producing cells of the heart blood and kidneys was about 100 times greater than that of the non-producing cells. These in vivo results were well comparable to the previous in vitro results and indicated that the inhibitor affected the invasion of the non-producing bacteria in the body in the model infection due to P. aeruginosa isolates consisting of the two types of cells. Similar results were obtained in mice with the model infection due to P. aeruginosa No. 5. Anti-pseudomonal drugs such as piperacillin (50 mg/mouse) and ceftazidime (50 mg/mouse) and sisomicin (1 mg/mouse) were given intramuscularly to mice infected concomitantly with both cells of P. aeruginosa No. 1.(ABSTRACT TRUNCATED AT 250 WORDS)     

Geographic distribution of medical supplies and the numbers of hospital inpatients in the secondary medical areas in Japan

A secondary medical area is defined as a medical administrative area under the Medical Care Law by which every prefectural government is expected to provide general medical care supplies such as beds for inpatients. This study evaluated the distribution in medical supplies among the secondary medical areas in Japan and the correlation between medical supply and demand. The numbers of hospital inpatients (residence of patients), physicians, and general beds excluding those for mental disorders and tuberculosis were analysed in relation to the population in all secondary medical areas in Japan. Those data were obtained from surveys conducted by the Ministry of Health and Welfare. The main results were as follows; 1) The distribution of physicians and general hospital beds among the secondary medical areas was not equal. 2) Even adjusted for the sex and age distribution, the highest hospital inpatients/population ratio among the secondary medical areas was four times as large as that of the lowest. 3) With multiple regression models, two independent variables (normal hospital beds/population ratio and aged 65 and over/total population ratio) accounted about 60% of the variance in hospital inpatients/population ratio. 4) The differences in medical supplies among the secondary medical areas may cause the differences in hospital inpatients/population ratio.     

OA&M framework for multiwavelength photonic transport networks

Photonic networks based on wavelength division multiplexing (WDM) and optical path technologies are expected to realize flexible, transparent, and cost-effective transport networks with a large transmission capacity. This paper explores the design framework of photonic transport networks taking into consideration the operation administration and maintenance (OA&M) functions required for the successful introduction of WDM systems based on the optical path concept. From the view point of network maintenance, clear distinction is made between the optical path layer and the optical section layer to facilitate accurate and smooth failure localization. The digital multiplexing span between physical multiplexing interfaces at the end-to-end digital nodes should have the same maintenance span as the corresponding optical path. We argue that cooperative maintenance by OA&M functions at both the digital and optical layers can be a practical way of network supervision. A supervisory (SV) signal transfer method and a configuration that is suitable for the terrestrial trunk network are also indicated. As an example, a practical SV system design methodology and an actual procedure developed for a single channel optical transmission system based on optical in-line amplifiers are introduced. Furthermore, application of the developed SV system and network restoration schemes is discussed for future WDM-based photonic networks. The OA&M aspects introduced will be valuable for creating future photonic network systems     

Oxidation behaviours of carbon/carbon composite with multi-coatings of LaB6-Si/polycarbosilane/SiO2

The influence of multi-coatings of LaB₆-Si/polycarbosilane/SiO₂ on the oxidation behaviour of carbon/carbon composite materials was investigated in the temperature range from 500 to 1400 °C. The additives of LaB₆-Si offered lower oxidation rates and accelerated increases in oxidation rates at temperatures below 900 °C. The coating of polycarbosilane (PCS) improved the compatibility of the coating on the carbon/carbon composite and lowered the oxidation rates of the LaB₆-Si coated composite below the transition temperature. With the SiO₂ coating, the cracks of the LaB₆-Si/PCS coating was sealed and a good oxidation resistance of the LaB₆-Si/PCS/SiO₂ coated composite was found at temperatures up to 1300 °C.     

A simplified cascade current‐source inverter interconnected to a single‐phase three‐wire distribution system and its application to electric energy storage systems with batteries

A novel current source inverter system interconnected to the single‐phase grid is proposed. It has the same construction as the conventional three‐phase current source inverter that is interconnected to the single‐phase three‐wire distribution system. Though the proposed circuit has no output transformer, it can be equivalently performed as the single‐phase double cascade inverter by diverting the pole transformer in the utility system. By controlling the appropriate scheme, the output currents can be obtained as the five‐level waveforms and their distortions can be decreased sufficiently. It is applied to the interactive electric energy storage system with batteries and the basic discharging characteristics are discussed experimentally. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10380     

Autonomic nervous function of the patients with neurally mediated syncope

Although diagnosis of neurally mediated syncope (NMS) using head-up tilt (HUT) test has been established, the exact mechanism of NMS has not yet been elucidated. We evaluated beta and alpha-adrenergic function in NMS patients by pharmacological autonomic function test. The alpha-adrenergic sensitivity of NMS patients was significantly lower than that of control subjects. The patients who need low dose isoproterenol for provocation of syncope showed higher beta-adrenergic sensitivity than patients who developed syncope without isoproterenol. Thus, pharmacological autonomic function test was useful for evaluation of NMS patients.