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Depositions of light-absorbing particles (LAPs), such as black carbon (BC) and dust, on the snow surface modulate the snow albedo; therefore, they are considered key factors of snow-atmosphere interaction in the present-day climate system. However, their detailed roles have not yet been fully elucidated, mainly due to the lack of in-situ measurements. Here, we develop a new model chain NHM-Chem-SMAP, which is composed of a detailed regional meteorology-chemistry model and a multilayered physical snowpack model, and evaluate it using LAPs concentrations data measured at Sapporo, Japan during the 2011-2012 winter. NHM-Chem-SMAP successfully reproduces the in-situ measured seasonal variations in the mass concentrations of BC and dust in the surface snowpack. Furthermore, we find that LAPs from domestic and foreign sources played a role in shortening the snow cover duration by 5 and 10 days, respectively, compared to the completely pure snow condition.

The spectral evolution of the nova V5587 Sgr has been monitored at Koyama Astronomical Observatory and Higashi-Hiroshima Observatory, Japan, from the early to nebula phase. The nova rebrightened several times. The spectra during the early phase showed emission lines of H α, H β, O I, He I, He II, N II, Fe II. Nova V5587 Sgr is classified into the Fe II type. The helium abundance of the nova is estimated as N(He)/N(H) = 0.134 ± 0.09. The light curve, the spectral evolution, and the helium abundance in V5587 Sgr are similar to those of the nova PW Vul.

Novae are generally considered to be hot astronomical objects and show effective temperatures up to 10,000 K or higher at their visual maximum. But, it is theoretically predicted that the outer envelope of the nova outflow can become cool enough to form molecules that would be dissociated at high temperatures. We detected strong absorption bands of C2 and CN radicals in the optical spectrum of Nova V2676 Oph, a very slow nova with dust formation. This is the first report of the detection of C2 and the second one of CN in novae during outburst. Although such simple molecules are predicted to form in the envelope of the outflow based on previous studies, there are few reports of their detection. In the case of V2676 Oph, the presence of the molecular envelope is considered to be very transient, lasting several days only.

Spectroscopic and photometric monitoring observations of nova Apl 2012 (V1724 Apl) were conducted at Koyama Astronomical Observatory, Fujii-Kurosaki Observatory and Bisei Astronomical Observatory. The nova was initially considered as an outbursting pre-main-sequence young stellar object. Our monitoring observations have revealed the nova to be a Fe II type classical nova. The temporal evolution of spectra and light curves of the nova were similar to those of a slow nova (e.g., V1280 Sco and V5558 Sgr). We observed no evidence of molecule formation in V1724 Aql in contrast with V2676 Oph in which dust formation occurred after the molecular formation in the nova outflow.

A thermoelectric (TE) power conditioner maintaining high efficiency over a wide input power range has been developed. Variable switching frequency operation is shown to give an improvement in efficient operating range. The input range showing more than 90% conversion efficiency is expanded to more than 25% by introducing a low-power controller circuit and variable switching frequency control. The TE power conditioner showed excellent response against a change in thermoelectric generator (TEG) output and load, making it suitable for automotive applications.

This paper describes a practical high-efficiency thermoelectric (TE) power conditioner with maximum power point tracking (MPPT) control for thermoelectric generators and the operation results for a battery load system. This power conditioner comprises a high-frequency step-up/step-down switching converter and a microcontroller; a synchronized switching circuit is introduced to achieve high conversion efficiency. Furthermore, it is equipped with a battery charge control program and has a maximum conversion efficiency of 96.7%. An impedance matching method developed for MPPT control showed excellent response against a change in the TEG output, making it suitable for solar TEGs as well as general applications.

Internal elastic strain, and its change accompanied with the raft formation during creep deformation in the Ni-based single crystal superalloy (TMS-26) have been investigated by X-ray diffractometry. The elastic strain caused by the lattice misfit between g and g' phases has markedly been changed by creep deformation especially in the directions perpendicular to the [001] tensile axis. The change in the elastic strain can be explained by the effect of creep dislocations stacked at g/g' interfaces. The evolution of the elastic stress field estimated from the elastic strain has explained well the transition from primary creep stage to the second one.

Recent innovative research and development of high performance thermoelectric materials for power generation in the temperature range from room temperature up to 1300K has been investigated. The concept of guiding principle for the enhancement of thermoelectric performance was briefly summarized including PGEC materials and independent control of the structure and function. In this paper as some of the promising materials, modified Bi-Te system, (filled) Skutterudites, clathrates and layered oxides were discussed.

Isothermal adsorption and desorption processes of In/Si(1 1 1) were studied by reflection high energy electron diffraction (RHEED) and fluorescent X-ray spectroscopy. In the isothermal adsorption process at room temperature, a sticking probability of In on Si(1 1 1) is unity even in a multilayer region, and the 7×7 structure is replaced by 1×1 during adsorption of In up to 2 monolayers (ML). In the isothermal desorption process at temperatures between 360 and 460 °C, superstructure of In/Si(1 1 1) changes to 1×1, 4×1, 31 × 31 , 3 × 3 , 7×7, in turn. Structure change and In desorption from each phase go together and all desorption rates are zeroth order. Activation energies of In desorption from 1×1, 4×1, 31 × 31 and 3 × 3 phases are estimated to 0.48, 1.5, 1.6 and 1.9 eV, respectively. From RHEED and isothermal desorption results, saturation coverage of 4×1 and 31 × 31 phases are estimated to be 0.96±0.15 and 0.56±0.06 ML, respectively.

Thermoelectric performance is detennined with three factors, namely, Seebeck coefficient ,electrical resistivity and thermal conductivity. For metal and single crystalline semiconductor, those factors have close interrelation each other. However, as the sintered thermoelectric element has various levels of superstructure from macro scale and micro scale in terms of the thermoelectric mechanism, the relationship among them is more complex than that for the melt-grown element, so it is suggested that the control of the temperature dependence of thermoelectric properties is possible to enhance the thermoelectric performance for wide temperature range due to FGM approach. The research objective is to investigate the characteristics of the thermoelectric properties for various doping levels and hot-pressed conditions to make the thermoelectric elements for which the temperature dependence of the performance is controlled due to FGM approach varying the doping levels and sintering conditions. By usage of the zone traveling hot-press sintering method to Antimony doped magnesium silicide synthesized by the spark plasma sintering method the continuously, functionally graded, sintered thermoelectric bulk element could be successfully made, and the distribution characteristics of thermoelectric properties were satisfactorily measured.

L-Ascorbic acid 2-phosphate magnesium salt (APM) is an L-ascorbic acid (AsA) derivative developed to improve AsA stability and display effective biochemical characteristics. This study aimed to investigate the effects of APM on the functions and properties of human gingival fibroblasts with respect to the prevention of periodontal disease in comparison with those of AsA.Human gingival fibroblasts were incubated in the presence or absence of APM or L-ascorbic acid sodium salt (AsANa). Intracellular AsA was analysed by HPLC. Collagen synthesis was measured by ELISA and real-time RT-PCR. Intracellular reactive oxygen species (ROS) induced by hydrogen peroxide (H(2)O(2)) were quantified using a fluorescence reagent, and cell damage was estimated with calcein acetoxymethyl ester. Furthermore, intracellular ROS induced by tumor necrosis factor-α (TNF-α) were quantified, and expression of TNF-α-induced interleukin-8 expression, which increases due to inflammatory reactions, was measured by ELISA and real-time RT-PCR.APM remarkably and continuously enhanced intracellular AsA and promoted type 1 collagen synthesis and mRNA expression. Furthermore, APM decreased cell damage through the suppression of H(2)O(2)-induced intracellular ROS and inhibited interleukin-8 production through the suppression of TNF-α-induced intracellular ROS. These effects of APM were superior to those of AsANa.These results suggest that APM is more effective than AsANa in terms of intake, collagen synthesis, decreasing cell damage and inhibiting interleukin-8 expression in human gingival fibroblasts. This suggests that local application of APM can help to prevent periodontal disease.

Thermoelectric power generation technology has been recognized to contribute to the realization of environment-friendly society all over the world in the future. Present status and future prospects on the thermoelectric power generation technology in Japan are overviewed. The thermoelectric applications for power generation have been mainly considered to be one of the waste heat recovery systems from industrial, private, and transportation sectors in the Japanese energy system. Such activities have been in progress in Japan. Then, several demonstration system tests and feasibility study have been achieved using practical heat sources such as industrial furnaces, motorcycles, solid waste incinerators, and solar thermal systems have been achieved mainly by private companies. Several topics of experimental results on advanced modules based on layered oxides, Heusler alloys, filled Skutterudites for power generation from the view points from environment-friendly and nanostrucuture approach are included. In the future prospects the recent R&D projects of advanced materials for thermoelectric power generation technology and the commercialization of thermoelectric power generation applications are discussed.

Tobacco smoking has been suggested to be one of the important risk factors of developing periodontal disease. Although epidemiological studies have shown the detrimental effects of smoking on periodontal disease, the effects of smoke compounds on gingival tissue are not well understood. The aim of this study was to evaluate the effects of nicotine, which is the major component of the thousands of chemicals that constitute cigarette smoke, for cytodifferentiation of murine periodontal ligament (MPDL) cell.Expression of nAChR subunits on MPDL cells was examined using RT-PCR. The effects of nicotine on gene expression of extracellular matrices and osteoblastic transcription factors were evaluated by quantitative RT-PCR. Mineralized nodule formation of nicotine-treated MPDL cells was characterized by alizarin red staining.Murine periodontal ligament cells expressed several subunits of nAChR, which have functional calcium signals in response to nicotine. Gene expression of extracellular matrices and osteoblastic transcription factors were reduced in nicotine-treated MPDL cells. In addition, mineralized nodule formation was inhibited in MPDL cells in the presence of nicotine.Our findings indicate that nicotine may negatively regulate the cytodifferentiation and mineralization of MPDL cells.

The role of the Harderian gland (HG) in the production of immunoglobulin, especially IgA, was investigated. Lacrimal immunoglobulin almost disappeared after surgical removal of the HG and immunoglobulin produced by HG cells was detected in saliva but not in the trachea. Immunoglobulin production occurred in HG cell culture in vitro and it consisted mostly of IgA; the production of IgM and IgG was very low. These findings indicate that lacrimal IgA is produced locally in the HG and lacrimal IgG and IgM are mostly transported from the blood.

A large scale Thermoelectric Generator System (TEG) has temperature distribution for both heat source and heat sink, leading mismatch power loss. The insertion of power conditioner witch has impedance matching ability between TEG and a load has a potential to recover the mismatch power loss of the system effectively. The practical maximum power point tracking (MPPT) conditioner for TEG with the size of 30times60 mm2, which can be used up to 30 W has been developed. The power conditioner is composed of Buck-Boost converter, internal power supply, and microcontroller. The microcontroller controls the virtual conductance of the load to match the internal conductance of the connected thermoelectric modules. The effect of MPPT power conditioner insertion is evaluated using the experimental TEG system, which composed of four thermoelectric module (TEM) strings. We confirmed each MPPT power conditioner connected in parallel maintains optimum operating condition. The results suggest that introducing MPPT power conditioner has a potential to reduce mismatch power loss and improve load matching ability of TEG system.

ldquoDevelopment for advanced thermoelectric conversion systemsrdquo supported by the new energy and industrial technology development organization (NEDO) has been successfully completed as one of the Japanese national energy conservation projects. Three types of the cascaded thermoelectric modules operating up to 850 K in high electrode temperature and two types of Bi-Te thermoelectric modules operating at 523 K in maximum electrode temperature in consideration with the durability have been developed. In order to proceed to the practical phase four types of advanced thermoelectric power generation systems have been experimentally demonstrated for the waste heat recovery from the industrial electric heating furnace, the waste heat recovery using two types heat exchanger systems from the diesel engine co-generation system, the waste heat recovery from a large scale electric transformer, and the waste heat recovery from a projector lamp. Results of the experiments on the performance and durability for the advanced modules and for the demonstration systems are summarized.

A technique to precisely measure the efficiency of thermoelectric modules has been developed within the framework of the Japanese project "The Development for Advanced Thermoelectric Conversion Systems" supported by the New Energy and Industrial Technology Development Organization (NEDO). For modules operating in the temperature difference of up to 550K, this technique can accurately measure both the heat flow rate through a module and the generated electrical power. Techniques to measure the efficiency of modules constructed by the different participating companies are crucial for the development of thermoelectric modules and for judging the progress of this project itself. However, neither commercially available modules that operate at temperatures above 573K are nor an efficiency measurement technique for such modules are readily available. At the laboratory level, relatively few evaluation systems for higher temperature modules have been developed. In this project, the measurement conditions for evaluation of such modules have been defined. Based on these defined conditions, we have developed an efficiency measurement system for different types of modules that operate in the temperature difference of up to 550K.

We demonstrate "3D-Mode," a software system that builds 3D models of objects and scenes by taking a few (minimally 2) photographs using a digital camera at possibly largely separated positions. It has recently been commercialized by 3D Media Co., Ltd. 3D-Mode has the following steps: (1) taking photos; (2) manually obtaining and matching a few feature points on the object; (3) automatically computing 3D structure and motion; (4) automatic Delaunay triangulation and manual modification; (5) automatic acquisition of texture for each triangular patch; (6) if necessary, assign a new coordinate system and scale of space. The system does not need input of camera parameters, but requires manual input of feature points in a special manner such that matching information is input simultaneously. Once epipolar lines are available, they are used to help locate corresponding points in other images.

The Japanese National Project "The Development for Advanced Thermoelectric Conversion Systems" supported by the New Energy and Industrial Technology Development Organization (NEDO) was started in FY2002 to be completed in FY2006.The final goal of the thermoelectric modules is to establish 15% in energy conversion efficiency with temperature difference of 550 K. Moreover, thermoelectric conversion systems technologies for high temperature waste heat to be applied to electric heating furnaces and diesel engines, as well as those for lower temperature one to be applied to projector lamps and large-scale electric transformers are being established for the realization of practical systems. By the end of 2004, the interim goal of the thermoelectric modules (12% in efficiency) and system technologies has already been cleared. The progress by the end of FY2004 and future prospects of the project are introduced.

Robust PWM power amplifiers whose transient response characteristics do not deteriorate against an extensive load change and/or direct-current power-supply voltage change are needed. In this paper, a digital robust controller with bumpless mode switching for PWM power amplifiers, which can satisfy such demands, is proposed. First, a nominal model of PWM power amplifiers which consist of a PWM signal generating part, an electric power conversion part and an LC filter is derived from the linear approximation. The controlled object is described by the discrete-time system with consideration of the input dead time. It is shown that a digital controller can be designed in the same way as the previously proposed digital controller and then the load range spreads more by bumpless mode switching. A DSP is implemented to the digital controller with bumpless mode switching. It is demonstrated from an experiment that a mode-switched digital controller is realizable.

Hot-press sintered thermoelectric elements of intermetallic compounds: Mg/sub 3/Bi/sub 2/ and Mg/sub 3/Sb/sub 2/ were examined for the feasibility as medium temperature range thermoelectric elements, which belong to the family of zinc blend crystal structure. The experiments were carried out varying the sintering temperature in order to find out the optimum morphology for the sintered material system, because the thermoelectric performance was affected with the macro- and micro-structure due to the sintering, process. Seebeck coefficients (S), electrical conductivity (/spl sigma/) and thermal conductivity (/spl kappa/) were measured in the temperature range from 300K to 773K. According to the Seebeck coefficient measurement, both materials were p-type semiconductor. As the results, the power factor (=S/sup 2//spl sigma/) could be obtained from 1.0x10/sup -3/ W/m/sup 2/K at 550K to 2.5x10/sup -3/ W/m/sup 2/K at 773K for Mg/sub 3/Bi/sub 2/ system and from 1.0x10/sup -3/ W/m/sup 2/K at 600K to 2.0x 10/sup -3/ W/m/sup 2/K at 740K for Mg/sub 3/Sb/sub 2/ system respectively. The measurement of thermal conductivity by laser flash method showed that the hot-press sintered Mg/sub 3/Sb/sub 2/ element had the relatively low thermal conductivity. The estimate for Mg/sub 3/Sb/sub 2/ elements promisingly shows the dimensionless figure of merit ZT of 0.55 at 660K.

This paper describes the comparison of operating point control methods such as maximum power point tracking control (MPPT) and a constant voltage control applied to the thermoelectric devices. To experimentally evaluate the power control methods, a one-chip micro controller controlled DC-DC converter was inserted between the thermoelectric module and a load. The derived power from the module by constant voltage control is the same with the MPPT control method if the temperature difference keeps constant value. On the other hand, a mismatch power loss of constant voltage method increases with a fluctuation magnitude from the reference value and the fluctuation frequency. The maximum mismatch power loss of constant voltage method by fluctuation is around 20% regardless of a change of maximum temperature difference when the reference output voltage coincides with the optimized value of the maximum temperature difference.

The effect of annealing process on thermoelectric properties has been researched for hot-press sintered chromium disilicide (CrSi/sub 2/) in order to enhance the thermoelectric performance. Annealing period under the proper annealing temperature was found to affect the transport properties such as carrier concentration, Hall mobility and scattering mechanisms, so that the thermoelectric properties such as the Seebeck coefficient and electrical conductivity were dependent on the annealing period. The experiments have been carried out for 0.9 atm% Ag-doped chromium disilicide produced by the hot-press sintering process varying annealing period of 12 h, 24 h, 36 h and 48 h at 1273 K in annealing temperature. The scattering mechanisms were changed with increasing the annealing periods to shift from the mixed mode of ionized impurity scattering with phonon scattering to single mode of phonon scattering for the temperature range from 300 K to 650 K. For the samples of more than 36 h in annealing period the phonon scattering mode was dominant for overall temperature range similar to that for a single crystal sample of undoped chromium disilicide. It was clarified that the annealing period highly affected thermoelectric performance and temperature dependence of thermoelectric properties and the optimum annealing process surely existed for 0.9 atm% Ag-doped, hot-press sintered CrSi/sub 2/ system. For example, the power factor was obtained 2.5/spl times/10/sup -3/ W/m/sup 2/K at 800 K in maximum for the sample of 24 h in annealing period, while it was 1.5/spl times/10/sup -3/ W/m/sup 2/K at 650 K in maximum for the hot-press sintered sample of no heat treatment.

We investigated thermoelectric properties of Fe-Si systems (/spl alpha/, /spl epsiv/ and /spl beta/-phase) with oxide particles diffused in. The oxides used here were La/sub 2/O/sub 3/, Yb/sub 2/O/sub 3/, Ag/sub 2/O, NiO and Cr/sub 2/O/sub 3/. They were sintered by solid reaction method, then they were annealed for 3 hours. We found that the shorter annealing time was obtained by adding a small amount of oxides, lattice thermal conductivity decreased by addition of Yb/sub 2/O/sub 3/. Interfacial effects were found that carriers moved between the solidified Ag and the Fe-Si systems by addition of Ag/sub 2/O, and the barrier between the oxides and the Fe-Si systems was observed by addition of La/sub 2/O/sub 3/ and Yb/sub 2/O/sub 3/. Figure of merit was the following in Fe/sub 0.92/Mn/sub 0.08/Si/sub 2/ after 3 hours annealing; Z=1.85/spl times/10/sup -4/ (K/sup -1/) for 3 wt% Yb/sub 2/O/sub 3/, Z=0.75/spl times/10 /sup 4/(K/sup -1/) for 3, 5 and 10 wt% Ag/sub 2/O and the unadded.

From the viewpoint of the most efficient utilization of fossil fuel resources as heat, the combustion temperature should be as high as possible to apply to the energy cascading system. Therefore, thermoelectric energy conversion as a topping system is recognized to be very important. High temperature metal silicides such as chromium silicide (M.P. 1763 K) and tungsten silicide (M.P. 2433 K) and so on have been known as a group of metal silicides. The spark plasma sintering method was selected to prepare thermoelectric elements of chromium silicide and tungsten silicide as examples of the high temperature, transition metal silicides. It is clarified that the spark plasma sintering method is very useful to make such a high temperature alloy. The temperature dependence of thermoelectric properties such as the Seebeck coefficient, electrical resistivity, power factor, thermal conductivity, carrier concentration and Hall mobility was measured to find out the preferable preparation conditions such as doping level and solid solution for these materials systems. The maximum power factor was 0.7/spl times/10/sup -02/ W/mK/sup 2/ at 900 K for chromium silicide, and 3.0/spl times/10/sup -02/ W/mK/sup 2/ at 1000 K for tungsten silicide as the p-type thermoelectric element respectively in the experiment.

The thermoelectric properties of the sintered magnesium compounds such as magnesium silicide and magnesium stannide have been researched in order to apply to a thermoelectric power generation system using combustion heat of municipal solid waste. Temperature dependencies of thermoelectric properties such as Seebeck coefficient, electrical resistivity and thermoelectric power factor are measured for the temperature range from 300 K to 770 K. The non-dimensional figure-of-merit for the sintered magnesium silicide is obtained about 0.4 at 600 K in the initial stage. The durability of magnesium compound elements is also discussed.

The status and future prospects on the development of thermoelectric power generation systems utilizing heat from the municipal solid waste in Japan are reviewed in this paper. Two ongoing research and development programs related to this application in Japan are briefly introduced. The characteristics of heat from the solid waste processing system lead to the peculiar concept of thermoelectric power generation system. The theoretical and experimental studies including small scale onsite experiment are shown to discuss several technological problems and the guideline for the development of such systems.

Intermetallic magnesium compounds and their solid solutions have been known as potentially promising thermoelectric materials for the middle temperature power generation application. Spark plasma sintering and subsequent hot-pressing were used to make the impurity doped Mg/sub 2/Si thermoelectric elements. The temperature dependence of thermoelectric properties such as the Seebeck coefficient, electrical conductivity and thermal conductivity was measured to clarify the optimum performance of sintered Mg/sub 2/Si elements. Moreover, the semiconducting properties such as Hall mobility and carrier concentration were measured by the van der Pauw method. In the case of 0.6 at%Sb doped n-type sintered elements the maximum power factor was obtained 3.0/spl times/10/sup -3/ W/mK/sup 2/ at 773 K and the figure of merit was 0.87/spl times/10/sup -3/ K/sup -1/ and dimensionless figure of merit ZT was 0.67. Concerning p-type Mg/sub 2/Si elements, silver doped, sintered Mg/sub 2/Si was made by the same procedure as n-type antimony doped sintered elements. The junction of a Mg/sub 2/Si element with the electrode was also studied to check the junction resistance between the thermoelectric element and the electrode. It was found that Fe was suitable as an electrode.

The characteristics of combustion heat from the municipal solid waste are fitted for a large-scale application of thermoelectric power generation potentially. The status and future prospects of thermoelectric power generation systems to recover electricity from this heat source in Japan are reviewed and discussed. Experimental results on three different types of small-scale (500 W class) thermoelectric power generation systems installed in the real municipal solid waste processing systems to demonstrate the technological feasibility and to extract the technological problems are briefly introduced. The conceptual designs of a small scale system for the next phase of the R&D program are presented. From the view point of large-scale realization the thermoelectric material and modules configurations required for this application are also discussed. A case study on the marginal cost estimation shows the cost reduction to be less than 0.4-0.5 Million Yen/kW in order to make a profit on this system.

An attempt was made to synthesize /spl beta/-Zn/sub 4/Sb/sub 3/ semiconducting compound by PIES (Pulverized and Intermixed Elements Sintering)/hot-pressing method. We found that it is possible to synthesize /spl beta/-Zn/sub 4/Sb/sub 3/ as a major phase without increased temperature when we start the ball milling process with a Zn-rich composition. The power factor /spl alpha//sup 2///spl rho/ at room temperature was 6.3/spl times/10/sup -4/ W/mK/sup 2/ and these initial data clarified that relatively high performance can be achieved with the PIES/hot-press method.

Efficient, inexpensive and non-toxic thermoelectric elements such as silicides should be developed for large scale application such as recovering the combustion heat of municipal solid waste, of which the characteristics are greatly fitted to thermoelectric power generation. This paper introduces the characterization and thermoelectric properties of undoped and doped n-type magnesium silicide processed by the powdered elements spark plasma sintering method. The patterns by powder X-ray diffractometry showed that it had typical polycrystalline phase. The temperature dependence of thermoelectric properties such as the Seebeck coefficient and electrical conductivity were measured for the temperature range from 300 K to 773 K. As a result, a power factor value 6.0/spl times/10/sup -4/ (W/mK/sup 2/) was obtained at 773 K for a doped sample.

Thermoelectric properties of metal silicides and their electrode bonding performance have been examined. Metal silicides such as chromium silicide, magnesium silicide and so on are environmentally friendly and abundant. These characters are very much important for thermoelectric power generation application. The thermoelectric properties of these materials made by the hot-press sintering method followed with spark plasma sintering method make them promising candidates for intermediate and high temperature thermoelectric applications, in particular, such as thermoelectric power generation topping co-generation system. The temperature dependence of thermoelectric performance such as the thermopower, electrical resistivity, power factor, thermal conductivity, carrier concentration, Hall mobility for Mn- and Ag- doped Chromium Silicide was characterized between room temperature and 1000 K. The shift of the peak performance of the power factor for the temperature range was observed with the dopant concentration. The electrode formation with magnesium silicide element was carried out using diffusion bonding method to Ta/Al/Mg/sub 2/Si system. The bonding characteristics were discussed from the viewpoint of the electrical performance and inspection of the diffusion behavior of the electrode and inserted metal at the junction layer.

Thermoelectric technology, in particular, thermoelectric power generation technology, has been recognized as one of the major energy conservation technologies in Japan. Recent outstanding results on the thermoelectric performance for various kinds of thermoelectric materials such as layered Co-based oxides, filled skutterudites etc. show a good potential for achieving high ZT values. These results encouraged and accelerated R&D activities of thermoelectric technology in Japan. This paper provides an overview of the present state of research and development on thermoelectric technology in Japan, and some prospects for the future. R&D results on thermoelectric energy recovery systems from solid waste combustion heat and from waste heat of gasoline engine vehicle carried out under several national projects is briefly introduced. Some of R&D activities of an enhancement of thermoelectric materials by universities and national research institutes are also presented as an example. The R&D effort of the lead-in research on the efficient thermoelectric module including novel high performance materials and proof-of-concept testing supported by NEDO, in which the objective is to arrange the coming national project on thermoelectric technology, is introduced. The development on thermoelectric cooling has been mainly carried out in private companies, which is not included in this paper. The potential contribution of thermoelectric technology to an energy system in Japan and the perspective on thermoelectric power generation technology are summarised.

A case of intestinal perforation caused by ESWL for left ureteral calculus is reported. A 69-year-old male underwent the graft replacement for bilateral iliac aneurysm in March, 1996. In February, 1999, there appeared left flank pain, and a diagnosis of left ureterolithiasis was made by radiological examination. On March 29 he was admitted to our department for ESWL. On March 30, ESWL for calculus in the pelvic region was performed with the patient in the prone position. The patient complained of the left lower abdominal pain immediately after ESWL, but no muscular defense was observed. Since the pain was not relieved, CT was performed on March 31, but no evident abnormal finding was found. Thereafter the pain continued and on April 2 muscular defense was also noted. On CT performed a second time, free air and evidence of ileus were found, so emergency operation was performed. Two perforations about 2 mm in size were found in the jejunum 130 cm from the Treitz' ligament, which led to diagnosis of intestinal perforation due to ESWL. The patient followed a satisfactory postoperative course and was discharged on April 23. There has been only one reported case of intestinal perforation due to ESWL. It is a very rare complication. However, this complication should be taken into consideration where the patient has the history of abdominal surgery and where ESWL was performed with the patient in the prone position.

A highly sensitive enzyme-linked immunosorbent assay (ELISA) for quantitation of Clostridium perfringens enterotoxin (CPE) by a sandwich method with polystyrene beads was elaborated. The ELISA was very sensitive with a detection limit of 1 pg/ml of CPE. Clostridium perfringens culture fluid did not interfere with the assay. This ELISA may be useful for the mass screening for Cl. perfringens producing small amounts of CPE.

The skeletal muscle is a very rare site of metastasis in renal cell carcinoma. We report the third case of skeletal muscle metastasis of renal cell carcinoma effectively treated with interferon-alpha. The patient was a 74-year-old woman who had undergone radical nephrectomy on the left side for renal cell carcinoma on April 23, 1990, and had been observed as an outpatient. In June 1997, she was admitted with a diagnosis of metastasis in the left great adductor muscle and right sixth rib, as well as multiple lung metastasis. The metastatic lesion in the great adductor muscle decreased in size by more than 50% following concomitant intramuscular administration of natural interferon-alpha (nIFN-alpha). In the other metastatic lesions, nIFN-alpha-sensitive and resistant metastatic foci were intermingled. Thus, the primary focus in the present study was presumably composed of several clones with different sensitivities to nIFN-alpha.

The patient was a 67-year-old woman who had undergone radical hysterectomy and postoperative radiotherapy for cervical cancer at the age of 46 years. Spontaneous rupture of the urinary bladder occurred twice in 1997, and conservative treatment was performed on each occasion. She was admitted to our hospital for the third time of spontaneous rupture of the urinary bladder. She underwent bilateral cutaneous ureterostomy because of panperitonitis and paralytic ileus. A review of 11 cases of recurrent rupture of the urinary bladder reported in Japan including the present case revealed that, patients who had been conservatively treated tended to be subject to recurrence. However, the risk of recurrence remains when a partial cystectomy is performed. Therefore, especially in recurrent cases, augmentation cystoplasty or urinary diversion should be considered as the treatment for spontaneous rupture of the urinary bladder due to radiation cystitis.

Lactate can be viewed as a metabolic dead end in that it can only be produced or utilized via pyruvate. Lactate production is determined primarily by pyruvate concentration and to a lesser extend by the redox state. Increased lactate production may result from tissue hypoxia, alkalosis, catecholamine and alanine transamination to pyruvate. Hyperlactatemia is observed in many pathological conditions. Current diagnostic criteria for lactic acidosis are a pH less than 7.35 and lactate concentration greater than 5 to 6 mmol/l. In our study series, malignancy was the most common underlying disease accompanied by lactic acidosis. Organ failure, cardiovascular disease and diabetes mellitus were also common. The prognosis of patients with these diseases were grave. In cases of lactic acidosis associated with diabetes mellitus, alcoholic liver disease, rhabdomyolysis and diabetic comas were noticeable as complications. Alcohol abuse was the most common cause of lactic acidosis associated with diabetes mellitus. In these cases, laboratory data showed prominent hyperlactatemia, hyperglycemia and acidemia and elevated anion gap. The mortality rate in these cases was 36% and higher in cases with organ failure. Treatment of lactic acidosis consists of alkalization by sodium bicarbonate with carbicarb, insulin-glucose-infusion, dichloroacetate therapy, tham administration, bicarbonate-buffered peritoneal dialysis and high bicarbonate-containing dialysis.

This study was designed to evaluate the significance of the Harderian gland (HG) in the chicken IgA-production system by investigating the influence of HG on the increase of surface IgA (sIgA)-positive cells in other lymphoid organs and also the possibility of migration of HG lymphocytes into other organs. Non-contact culture of splenic or caecal tonsil (CT) lymphocytes with HG whole cells did not enhance the expression of sIgA. The experiment of HG lymphocyte transfer showed that the transferred HG lymphocytes migrated mainly into the CT in the 3-week-old recipient, and mainly into the CT and bursa of Fabricius (BF) in the 6-week-old recipient. It was also found that the transferred sIgA-positive HG lymphocytes migrated selectively into CT in both 3-week-old and 6-week-old recipients. These results indicated that chicken HG plays a central role not only in governing the local immunity in the eyes and respiratory tract but also as an organ which supplies precursory IgA-producing cells involved in local immunity in the intestine.