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A power storage system using spherical Si solar cells, lithium-ion battery and a direct current-alternating current (DC-AC) converter was constructed. A small and light inverter system was developed by combining a maximum power point tracking charge controller, direct current-direct current (DC-DC) converter, and DC-AC converter. Performance evaluation of the inverter system with SiC field-effect transistors (FET) and Schottky barrier diodes (SBD) was carried out, and the DC-AC conversion efficiencies and their stability of the inverter were improved compared with those of the ordinary Si-FET/SBD based inverter.

Arsenic (As) and chlorine (Cl) were co-doped to CH3NH3PbI3 perovskite solar cells, and the photovoltaic properties were investigated. AsI3 and NH4Cl were added to perovskite precursor solution, which were deposited on mesoporous TiO2 by a spin-coating combining an air flow method. Current density-voltage characteristics and incident photon-to-current conversion efficiencies were improved by the co-doping of As and Cl to the perovskite phase, which also indicated an energy gap of 1.57 eV. X-ray diffraction showed suppression of PbI2 formation by the AsI3 addition. The structure analysis by scanning electron microscopy indicated formation of a homogeneous microstructure by adding AsI3 with NH4Cl, which would result in the improvement of the photovoltaic properties.

100-W class power storage systems were developed, which comprised spherical Si solar cells, a maximum power point tracking charge control-ler, a lithium-ion battery, and one of two different types of direct current (DC)-alter- nating current (AC) converters. One inverter used SiC met-al-oxide-semicon-ductor field-effect transistors (MOSFETs) as switching devices while the other used Si MOSFETs. In these 100-W class inverters, the ON resistance was considered to have little influence on the efficiency. Nevertheless, the SiC-based inverter exhibited an approximately 3% higher DC-AC conversion efficiency than the Si-based inverter. Power loss analysis indicated that the higher efficiency resulted predominantly from lower switching and reverse recovery losses in the SiC MOSFETs compared with in the Si MOSFETs.

Perovskite-type photovoltaic devices with polysilane hole transport layers were fabricated by a spin-coating method. In the present work, poly(methyl phenylsilane) (PMPS) and decaphenylcyclopentasilane (DPPS) were used as the hole transport layers. First, structural and optical properties of the PMPS and DPPS films were investigated, and the as-prepared PMPS and DPPS films were amorphous. Optical absorption spectra of the amorphous PMPS and DPPS showed some marked features due to the nature of polysilanes. Then, microstructures, optical and photovoltaic properties of the perovskite-type photovoltaic devices with polysilane hole transport layers were investigated. Current density-voltage characteristics and incident photon to current conversion efficiency of the photovoltaic devices with the polysilane layers showed different photovoltaic performance each other, attributed to molecular structures of the polysilanes and Si content in the present hole transport layers.

In this paper, structural and photovoltaic properties of perovskite CH3NH3PbI3-xClx solar cells added with ammonium iodide (NH4I) are reported. The CH3NH3PbI3-xClx photovoltaic cells were fabricated by a hot air blow-assisted spin-coating method. By addition of NH4I, photovoltaic performance of the CH3NH3PbI3-xClx cell fabricated by the hot air blow-assisted spin-coating method was improved. The microstructure analysis of the resulting cells showed that the NH4I− added CH3NH3PbI3-xClx film was highly oriented along the (100) plane. Moreover, morphological changes of the NH4I− added CH3NH3PbI3-xClx film due to NH4I addition were also observed. The improvements of the photovoltaic performance, the crystal orientation, and the morphological changes of the CH3NH3PbI3-xClx are attributed to NH4I addition.

Inflammatory myofibroblastic tumor (IMT) is a rare but benign entity masquerading as a malignant tumor. We herein report an 18-month-old boy with small bowel wall IMT who presented with intussusception. He was transferred to our hospital with a complaint of abdominal pain and diagnosed with intussusception. On laparotomy, the small bowel wall mass consisted of solid tissue measuring 2.5 × 3.0 cm. The postoperative pathology examination revealed numerous spindle cells arranged in dense bundles with diffuse infiltration of inflammatory cells and tumor involvement of the mucosa and serosa. As the postoperative pathology examination resulted in a diagnosis of IMT and suspected partial resection, small bowel resection and mesenteric lymph node resection were performed two months after the first operation. A pathology examination after the second surgery revealed no evidence of residual IMT and negative findings for metastasis in the regional lymph nodes. IMT is a locally aggressive lesion. The immunophenotypic feature of ALK-1 in particular is associated with a high recurrence rate. Long-term follow-up is absolutely needed. Keywords: Inflammatory myofibroblastic tumour, Small intestine, Child, Intussusception, Anaplastic lymphoma kinase

Photovoltaic properties of copper (Cu)-doped perovskite (CH3NH3PbCuxI3+x) photovoltaic devices with different Cu content were investigated. The CH3NH3PbCuxI3+x films were polycrystalline with a tetragonal system, and their lattice constants and crystallite size varied with Cu doping. Compared to conversion efficiencies of non-doped CH3NH3PbI3 photovoltaic device, those of CH3NH3PbCuxI3+x photovoltaic devises increased. The improvement of photovoltaic properties was attributed to partial substitution of Cu at the Pb sites.

Surface and inside of silicon (Si) spheres prepared by a powder melting method were investigated. The lattice constant of the inside of Si spheres was larger than that of the surface of Si spheres, which was due to interstitial atoms trapped at gettering sites. To obtain the evidence for existence of the impurities, composition analysis was carried out. Florescence spectra of the surface and inside of Si spheres exhibited some information on impurities in both Si spheres.

Effects of AsI3 and NH4Cl addition to perovskite CH3NH3PbI3 precursor solutions on photovoltaic properties were investigated. TiO2/CH3NH3Pb(As)I3(Cl)-based photovoltaic devices were fabricated by a spin-coating technique, and the microstructures of the devices were investigated by X-ray diffraction and scanning electron microscopy. Current density-voltage characteristics and incident photon-to-current conversion efficiencies were improved by a small amount of As- and Cl-doping, which resulted in improvement of the efficiencies of the devices.

This article reports comparative study of 150-300 W class photovoltaic inverters (Si inverter, SiC inverter 1, and SiC inverter 2). In these sub-kW class inverters, the ON-resistance was considered to have little influence on the efficiency. The developed SiC inverters, however, have exhibited an approximately 3% higher direct current (DC)-alternating current (AC) conversion efficiency as compared to the Si inverter. Power loss analysis indicated a reduction in the switching and reverse recovery losses of SiC metal-oxide-semiconductor field-effect transistors used for the DC-AC converter is responsible for this improvement. In the SiC inverter 2, an increase of the switching frequency up to 100 kHz achieved a state-of-the-art combination of the weight (1.25 kg) and the volume (1260 cm3) as a 150-250 W class inverter. Even though the increased switching frequency should cause the increase of the switching losses, the SiC inverter 2 exhibited an efficiency comparable to the SiC inverter 1 with a switching f...

Perovskite-type CH3NH3(MA)PbI3−based photovoltaic devices were fabricated and characterized. Doping effects of cesium iodide (CsI), cesium bromide (CsBr) and tin bromide (SnBr2) on the photovoltaic properties and surface microstructures of the perovskite phase were investigated. Short-circuit current densities, open-circuit voltages and fill factors increased by CsI and SnBr2 addition. The surface coverage of the perovskite crystals was also improved by SnBr2 doping, which resulted in improvement of the fill factor. The cell prepared by a starting composition of MA0.95Cs0.05Pb0.95Sn0.05I2.90Br0.10 showed the best photovoltaic performance in the present work.

Bismuth ferrite (BiFeO3) thin films were prepared by a spin-coating method. Crystal structure and optical properties of the BiFeO3 films were evaluated using X-ray diffraction. The lattice constants, crystallite size, and energy gap of BiFeO3 films depended on the concentration of the BiFeO3 precursor solution. BiFeO3/CH3NH3PbI3 photovoltaic devices were fabricated to investigate photovoltaic properties of BiFeO3. Current density–voltage characteristics of the photovoltaic devices showed rectifying behavior, indicating that BiFeO3 worked as an electron transport layer in CH3NH3PbI3-based photovoltaic devices.

A photovoltaic power generation system using spherical silicon (Si) solar cells and silicon carbide (SiC) field effect transistor (FET) inverter for photovoltaic applications was constructed and evaluated. The spherical Si solar cells were connected to the SiC-FET inverter and were used as a power source. Comparing the photovoltaic power generation system using an ordinary Si-FET inverter, direct current-alternating current conversion efficiencies of the SiC-FET inverter were improved due to reduction of power loss in the SiC-FET inverter.

ZnO nanorods/perovskite solar cells with different lengths of ZnO nanorods were fabricated. The ZnO nanorods were prepared by chemical bath deposition and directly confirmed to be hexagon-shaped nanorods. The lengths of the ZnO nanorads were controlled by deposition condition of ZnO seed layer. Photovoltaic properties of the ZnO nanorods/CH3NH3PbI3 solar cells were investigated by measuring current density-voltage characteristics and incident photon to current conversion efficiency. The highest conversion efficiency was obtained in ZnO nanorods/CH3NH3PbI3 with the longest ZnO nanorods.

Microstructures, optical and photovoltaic properties of CH3NH3PbI3(1−x)Cl x perovskite films with copper(I) thiocyanate (CuSCN) additive were investigated. The CuSCN-added CH3NH3PbI3(1−x)Cl x films were prepared by a hot air blow-assisted spin-coating method. Current density–voltage characteristics of the photovoltaic device using the CuSCN-added CH3NH3PbI3(1−x)Cl x light-absorbing layer showed increases in short-circuit current density, open-circuit voltage, which resulted in increase in the conversion efficiency. Microstructure analysis showed that the crystal structure of the CuSCN-added CH3NH3PbI3(1−x)Cl x was a pseudocubic system. From these results, partial substitutions of Pb2+ and anions (I− and Cl−) by Cu ions (Cu+ and Cu2+) and SCN−, respectively, are considered to occur in the CuSCN-added CH3NH3PbI3(1−x)Cl x films. Based on the obtained results, reaction mechanisms of the CH3NH3PbI3(1−x)Cl x films with and without CuSCN additive were discussed.

Perpendicularly magnetized layers are used widely for high-density information storage in magnetic hard disk drives and nonvolatile magnetic random access memories. Writing and erasing of information in these devices is implemented by magnetization switching in local magnetic fields or via intense pulses of electric current. Improvements in energy efficiency could be obtained when the reorientation of perpendicular magnetization is controlled by an electric field. Here, we report on reversible electric-field-driven out-of-plane to in-plane magnetization switching in Cu/Ni multilayers on ferroelectric BaTiO3 at room temperature. Fully deterministic magnetic switching in this hybrid material system is based on efficient strain transfer from ferroelastic domains in BaTiO3 and the high sensitivity of perpendicular magnetic anisotropy in Cu/Ni to electric-field-induced strain modulations. We also demonstrate that the magnetoelectric coupling effect can be used to realize 180° magnetization reversal if the out-of-plane symmetry of magnetic anisotropy is temporarily broken by a small magnetic field. An electric-field switching technique can lower the energy required to write and erase data in high-density magnetic storage devices. Perpendicularly magnetic recording is a new technology that aligns magnetic bits into vertical arrangements using specially constructed multilayer films. Normally, magnetic fields or intense bursts of electric currents are needed to modify individual bits. Tomoyasu Taniyama from the Tokyo Institute of Technology and international collaborators have discovered that growing perpendicularly magnetised copper-nickel multilayers on top of ferroelectric BaTiO3 crystals produces devices responsive to modest electric fields. Laser-based measurements and theoretical analysis revealed that this fast, reversible, and room temperature data switching method was driven by mechanical strain at the metal multilayer-ferroelectric interface. Successful results with films up to 65 nanometers thick indicate that this approach holds promise for practical spintronics applications. Reversible electric-field-driven magnetization switching between perpendicular-to-plane and in-plane orientations in Cu/Ni multilayers on ferroelectric BaTiO3 is demonstrated at room temperature. Fully deterministic magnetic switching is based on efficient strain transfer from ferroelastic domains in BaTiO3 and the high sensitivity of perpendicular magnetic anisotropy in Cu/Ni to electric-field-induced strain modulations. The magnetoelectric coupling effect can also be used to realize 180° magnetization reversal if the out-of-plane symmetry of magnetic anisotropy is temporarily broken by a small magnetic field.

Control of magnetic domain-wall motion by electric fields has recently attracted scientific attention because of its potential for magnetic logic and memory devices. Here, we report on a new driving mechanism that allows for magnetic domain-wall motion in an applied electric field without the concurrent use of a magnetic field or spin-polarized electric current. The mechanism is based on elastic coupling between magnetic and ferroelectric domain walls in multiferroic heterostructures. Pure electric-field-driven magnetic domain-wall motion is demonstrated for epitaxial Fe films on BaTiO3 with in-plane and out-of-plane polarized domains. In this system, magnetic domain-wall motion is fully reversible and the velocity of the walls varies exponentially as a function of out-of-plane electric-field strength.

Familial hypercholesterolemia is a rare inherited disease with an incidence of approximately one per million. Severe hypercholesterolemia is observed from the time of birth onwards. It is associated with severe atherosclerosis in childhood, leading to death from myocardial infarction before the age of 20 years. Liver transplantation is the only effective treatment for this disease. We experienced the case of an infant aged 2 years 5 months who had homozygous familial hypercholesterolemia and who received a liver graft from his father, who had familial heterozygous hypercholesterolemia. The pre-operative plasma cholesterol level was800 mg/dl. After liver transplantation, the recipient's cholesterol level decreased to 250 mg/dl after we administered the HMG-CoA reductase inhibitor. At present, 6 months after transplantation, the patient is doing well and free from a special diet. We can thus conclude that the combination therapy of liver transplantation from a donor with heterozygous familial hypercholesterolemia on cholesterol-lowering drugs is an effective therapy for a patient with the homozygous type of hypercholesterolemia.

This paper presents the effects of copper (Cu) addition on the photovoltaic properties of perovskite CH3NH3PbI3−xClx solar cells. The effects were investigated by measuring the current density–voltage (J–V) characteristics and external quantum efficiency. In the present work, CuBr and CuBr2 were used as additives. The photovoltaic properties of the CuBr-added CH3NH3PbI3−xClx devices showed a clear improvement. Structural and optical properties of the CuBr- and CuBr2-added CH3NH3PbI3−xClx films were also investigated. Based on the present results, the changes in the photovoltaic properties were discussed.

Effects of polysilane-doped 2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamino)-9,9′-spirobifluorene (spiro-OMeTAD) hole transport layers on photovoltaic properties were investigated by measuring current density–voltage characteristics and incident photon-to-current conversion efficiency of CH3NH3PbI3-based photovoltaic devices. Three kinds of polysilanes were used as the dopants. Due to the polysilane doping, conversion efficiencies of the CH3NH3PbI3 devices using the polysilane-doped hole transport layers were improved. Microstructures of the CH3NH3PbI3 devices were also investigated. Based on the results of the microstructure analysis, impact of silicon in the polysilanes doped into spiro-OMeTAD layer on photovoltaic properties were discussed.

ISHIBASHI, S., NAMIKI, K., ABE, M., SHIRAHATA, Y., OHNISHI, K., TOYODA, T. and OHUCHI, K. Cystic Adventitial Disease of the Popliteal Artery-A Case of Young Boy. Tohoku J. Exp. Med., 1995, 176 (3), 173-180-Cystic adventitial disease (CAD) of the popliteal artery (PA) is rare but one of the well-recognized causes of intermittent claudication. Now more than 200 case reports are available in the world, but there are only 6 cases younger than 15 years old. In this paper, we report a case of 14-year-old boy with CAD of the PA found by intermittent claudication. On examination, the pulses were not palpable below the right popliteal artery, and the angiography demonstrated about 1.5 cm-long obstruction of the right PA. We operated a resection of a cyst with artery, and replaced the autovein graft (V. saphena magna). Cyst contained mucoid degeneration-like ganglion. Two weeks after operation, the angiography showed no stenotic lesion, and follow-up at 4 years showed no symptoms.

We report a rare case of a 68-year-old male with metachronous pancreatic metastasis that was resected 2 years after salvage esophagectomy for local recurrence of esophageal squamous cell carcinoma (ESCC). Two years and 8 mo ago, he had undergone definitive chemoradiotherapy for the lower thoracic ESCC and achieved a complete response. Chemoradiotherapy used the protocol of the Japan Clinical Oncology Group trial 9906. Approximately 8 mo later, he developed a local recurrence of the ESCC and underwent thoracoscopic salvage esophagectomy followed by reconstruction with a conduit colon graft via a subcutaneous route. Recently, a tumor of the pancreatic body was found on routine follow-up computed tomography (CT). The tumor diameter was 15 mm on CT, and the maximum standardized uptake value of the lesion was 5.49 at 18F-2-fluoro-2-deoxy-D-glucose positron-emission tomography, strongly suggesting pancreatic cancer. In addition, all tumor markers were within the reference intervals. Therefore, distal pancreatectomy was performed with the resultant histological diagnosis being confirmed as pancreatic metastasis of the ESCC. He was treated with adjuvant chemotherapy, and there has been no evidence of recurrence 9 mo after the surgery. Resection of pancreatic metastasis offers a good prognosis and should be considered for solitary ESCC metastasis.

We retrospectively assessed the safety of the donor operation, based on parameters such as blood loss, blood transfusion, operation time, duration of hospitalization, and complications. Forty-five pediatric and adult recipients underwent living-donor liver transplantation (LDLTx) in Tohoku University Hospital from July 1991 to October 2000. Donor operations were classified into three groups. In the LS group, the graft was the lateral segment ( n=20); in the LL group, the graft was the left lobe without the middle hepatic vein ( n=16); and in the LLM group, the graft was the left lobe with the middle hepatic vein ( n=9). No significant differences were observed among the three groups regarding postoperative liver function or duration of hospitalization. In the LS group, the operation time was shorter and the requirement of autologous blood transfusion was significantly lower than in the other two groups. Most complications following retrieval of the graft were minor. Safety is guaranteed when the left lobe or the left lateral segment is used for LDLTx, but meticulous management of the operation is required to prevent complications.

We report on domain formation and magnetization reversal in epitaxial Fe films on ferroelectric BaTiO3 substrates with ferroelastica–c stripe domains. The Fe films exhibit biaxial magnetic anisotropy on top of c domains with out-of-plane polarization, whereas the in-plane lattice elongation of a domains induces uniaxial magnetoelasticanisotropy via inverse magnetostriction. The strong modulation of magnetic anisotropy symmetry results in full imprinting of the a–c domain pattern in the Fe films. Exchange and magnetostaticinteractions between neighboring magnetic stripes further influence magnetization reversal and pattern formation within the a and c domains.

Undoped polycrystalline AgInSe2 crystals were successfully grown at low temperature (650°C) using a hot-press method. The sizes of the samples were 2 cm in diameter. The largest grain size was approximately 90 nm. The presence of lattice defects such as Ag interstitials might lead to an enhancement in n-type electrical conductivity. The crystals had a resistivity of 2.2 Ω cm, a carrier concentration of 4.2 × 1016 cm3 and a mobility of 70 cm2V-1s-1 obtained by Hall measurement at RT.