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Rigid–rigid blends made of ionomer and ionomer precursor polymer, based on poly(methyl methacrylate) (PMMA), have been investigated. Two series of blends have been prepared for studying mechanical properties. In one series, dynamic mechanical properties were determined over a wide range of temperatures. As the weight fraction of the ionomer was increased, there was a modest increase of modulus at ambient temperature and a very large increase in the rubbery modulus at elevated temperatures above the glass transition temperature of PMMA. In a second series of tests, tensile stress–strain measurements, made at an ambient temperature, were carried out over a wide range of blend compositions. For all blends tested, the mechanical properties exhibited a synergistic enhancement, i.e., average values of modulus, strength and fracture energy were all higher than expected based on the rule of mixtures. Measurements of fracture toughness also exhibited synergy, with a maximum value, higher than the value of either blend component, being attained in blends containing about 30 wt % of the PMMA ionomer. These results are interpreted in terms of a higher resistance to fracture of the more chain-entangled ionomer phase and good interfacial adhesion between the two components of the blend. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1235–1245, 1998

We have designed and constructed a 500kVA-class oxide-superconducting power transformer. The windings are cooled by liquid nitrogen or subcooled nitrogen in a G-FRP cryostat of 785mm in diameter and 1, 210mm in height, that has a room-temperature space for an iron core with the diameter of 314mm. The primary and secondary windings are three-strand and six-strand parallel conductors of a Bi-2223 multifilamentary tape with silver sheath, respectively. The strand of 0.22mm thick and 3.5mm wide has 61 filaments with no twisting. The ratio of superconductor is 0.284. In the parallel conductors, the strands are transposed five times in each layer for a uniform current distribution among them. It was proved that the transformer has the rated capacity of 500kVA by means of two-hours short-circuit test and half-hour no-load test in liquid nitrogen of 77K. The efficiency is estimated as 99.1% from a core loss of 2.3kW and a thermal load of 2.2kW in coolant. The latter is composed of AC losses in windings and heat leakage from the cryostat and current leads, and is multiplied by a refrigeration penalty of liquid nitrogen, 20. Load test was also performed up to 500kVA. The transformer was furthermore operated in subcooled nitrogen at 66K with no quenching up to a critical level, that is equivalent to 800kVA. The efficiency estimated was improved to 99.3% in subcooled nitrogen. Measured AC loss in both windings are well explained by a theoretical prediction with the ‘critical state model.’ We also discuss prospective applications of the parallel conductors composed of advanced HTS multifilamentary tapes to AC windings with large current capacity.

The influence of a polar plasticizer glycerol, and a nonpolar plasticizer, dioctylphthalate (DOP), on the microstructure and relaxation properties of poly(methyl methacrylate) ionomers has been investigated by dynamic mechanical thermal analysis. The test results indicate that glycerol strongly interacts with and weakens the ionic cluster ‘phase’, and also significantly increases the mobility of backbone hydrocarbon chains in the multiplet-containing matrix phase. In contrast, the nonpolar plasticizer DOP is more selective in that it appreciably reduces the glass transition temperature of the hydrocarbon-rich matrix phase, but has a much smaller effect than glycerol on the glass transition temperature of the ion-rich cluster ‘phase’. The present results are compared and contrasted with the effects of the same two plasticizers on polystyrene ionomers.

The authors have designed and fabricated a 500 kVA-class oxide superconducting power transformer operated in sub-cooled nitrogen. The primary and secondary windings are three- and six-strand parallel conductors of Bi-2223 Ag-sheathed multifilamentary tapes, respectively. In the parallel conductors, the strands are transposed several times for uniform current distribution among them. A transformer, cooled by liquid nitrogen of 77 K, was steadily operated with a 500 kVA secondary inductive load. The efficiency in full operation at 77 K was 99.1 %, even with the refrigeration penalty of liquid nitrogen, 20, for the thermal load to the coolant. They installed the transformer in a continuous flow system of sub-cooled nitrogen as a fundamental step for compact superconducting transformers operating in sub-cooled nitrogen with a single-stage refrigerator. Short-circuit tests of the transformer were also performed in a region of temperature below 70 K. The transformer was operated with no quenching up to a level of critical current at 66 K, that is equivalent to 800 kVA. The efficiency estimated was improved to 99.3 % in the sub-cooled nitrogen.

Ionic naphthalene thermotropic polymers (NTP) based on wholly aromatic (main chain liquid crystalline) copolyesters were prepared, in which ionic monomer was introduced in the form of sodium 5-sulfoisophthalate. This meta-linked monomer introduces ionic groups as well as kinked units into polymer chains. A fiber-forming molecular weight was achieved for all the ionic NTP. The melt of ionic NTP showed extensive birefringence, and the majority of them exhibited nematic mesophase textures over a wide temperature range, without showing a transition to an isotropic phase at least up to 380 °C. The melting temperature (T m ) and the crystallization temperature (T c ) of the ionic NTP are both decreased substantially with an increase in ion-containing monomer content because of an increase of the number ofkinked units. A unique glass transition behavior is also observed: at the ionic content of less than 10 mol %, the glass transition temperature (T g ) is rather constant, the T g value jumps when the ionic content reaches 15 mol %, and two distinct T g 's with ca. a 40 deg separation are observed at 20 mol % ionic content. This seems to arise from the competition between two opposing factors: one is a reduction of the rigidity of backbone chains by kinked units, which leads to lower T g , and another is intermolecular ionic interactions between chains, which lead to higher T g . Fracture surfaces of the ionic NTP fibers indicate suppression of spontaneous fibrillation with an increase of ionic content. This is an indication of decreased rigidity of the backbone chains and increased cohesion through ionic interactions between the polymer chains. Also, flat fracture surfaces observed for the high ionic content NTP fibers reflect their brittleness, arising from easier crack propagation.

Development of SF6 gas-insulated switches that have a long service life and are highly reliable at medium voltage ratings require arc erosion of contacts in SF6 gas to be decreased. The effects of SF6 gas pressure and magnetic field for arc blow-out on erosion were studied experimentally in detail using sintered Cu-W contacts. The test current, SF6 pressure and magnetic field were 100 to 400 A, 0.1 to 0.6 MPa and 0 to 50 mT, respectively. The results show that the arc erosion rate increased linearly with the SF6 pressure. The magnetic field effectively reduced anode erosion (i.e., the application of a mere 50 mT lowered the erosion rate to 1/3 to 1/4). These phenomena may be attributed, respectively, to the increase in evaporation rate according to the shrinkage of arcing spot areas caused SF6 pressure and a decrease of the evaporation rate correlating to high-speed movement of the arcing spot on the anode by the magnetic field. However, the cathode erosion was insensitive to the magnetic field. The influence of both W grain size and composition ratio, Cu:W, on the erosion rate was also studied. The smaller W grain at Cu content of 50 to 70 wt.% was found to be best for suppression of erosion under the present conditions. Further, the increase of N2 mixture ratio to SF6 under constant total gas pressure greatly decreased contact erosion. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 118 (1): 41–51, 1997

近年，糸球体上皮細胞，Podocyteへの関心が高まりつつある。これはPodocyteが糸球体濾過機能に重要な役割を演じていることや糸球体障害の発症，進展機序にも深く関わっていることが明らかになりつつあることによる。我々もこれらの流れの中でPodocyte障害を臨床病理学的に評価したいと考え，一連の研究 を進めてきた1)～9)。そしてPodocyte障害の結果として，尿中にPodocyteが細胞としてあるいは細胞破片として出現することを見い出した。その際，尿中のPodocyteを検出するには尿沈渣の蛍光抗体法という極めて簡便な方法を用いた。我々の施設での尿中Podocyte検査は最初，一人の医師によってなされた。従って，検査結果の評価はバイアスがかかる可能性が十分にあった。そこで検査手技が簡便であることから，検査を病院の複数の検査技師にお願いし，同一の評価基準となるよう指導し，尿中Podocyte検査を依頼した。彼等は臨床データを知らされていないので，よりバイアスのかからない状況で検査が可能となった。そしてこのデータを解析してみると，驚いたことに彼等によって検査されても，一人の医師によって出された結果となんら変わるところがなかった。我々はこの結果に自信を得，これならば尿中Podocyte検査の評価基準を一定にすれば，どこの施設でも，誰が検査を行っても一定の結果が出せる，すなわち客観的な検査法となりうる可能性があると考えた。そこで，この考えを大手検査センターに話してみたところ，協力してもよいとの御返事をいただいた。そして全国いずれの施設からも同一の方法で検体を提出し，一カ所の検査センターで検査を行うという構想ができ上がった。そのためには研究会を設立し，全国多施設に協力をお願いして，この検査の有用性を検討するのが最善と考え，糸球体上皮細胞研究会が発足することになった。

半月体形成性腎炎は予後不良の糸球体疾患である。我々は実験モデルでその解析を行なっている。WKYラットにごく少量の抗糸球体基底膜抗体を投与して得られる半月体形成性腎炎モデルは，CD8陽性リンパ球 (CD8) とそれに続く多数のマクロファージ (Mφ) の糸球体内浸潤を特徴とする。我々はモノクローナル抗体を用いてこれらの細胞浸潤を抑制することにより，この腎炎の発症を抑制することを試みた。1) CD8の抑制により蛋白尿や半月体形成をほぼ完全に抑制できるが，この時糸球体内Mφ浸潤も抑制されており，糸球体内ICAM-1mRNA発現も低下していた。2) MCP-1のモノクローナル抗体投与により，腎炎4日目ではCD8を抑制せずにMφのみを抑制でき，この時蛋白尿が抑制された。以上より，半月体形成性腎炎の発症には浸潤細胞，直接的には特にMφの関与が重要であると考えられた。

The artery and vein of the transplanted kidney are generally anastomosed to the external iliac artery and vein, respectively. Therefore, in open abdominal artery aneurysm (AAA) repair in renal transplant patients, kidney ischemia due to a proximal aortic clamp is a serious problem. We successfully performed endovascular aneurysm repair (EVAR) of AAA without aortic clamping in two renal transplant recipient cases. The two patients were diagnosed with large AAAs following the renal transplant, and EVAR was performed. To protect the renal function, we used N-acetylcysteine premedication and hydration before the operation, and we could then reduce the iodine contrast medium by using echography of the artery during the operation. In this report, a case where EVAR with renal function protection is a useful treatment for renal transplant recipients with AAA is described.

Saltfreepolyelectrolytebehaviourwhichistypica llyobservedatlowpolymerconcentrationsforpoly electrolyte� aqueoussolutionsandrandomionomernonaqueousso lutions�(inpolarsolvents)�(i.e.,�negativeangular � dependenceofthereciprocalscatteringinstaticl ightscatteringandanappearanceofthefastmode� indynamic� lightscattering)�hasbeenobservedformonotelechelicionomersolutionsinapolarsolvent.�Thisindicatesthat� onlysinglecharge (perchain)�issufficienttoproduce� intermolecularelectrostaticinteractions, whichare� responsibleforsuchcharacteristicbehaviour.�Howe ver,�the�'characteristic'�behaviour,�whichistypic ally� observedathigherconcentrationsforpolyelectroly teandrandomionomersolutions�(i.e.,�largepositi veapparent� radiusofgyrationinstaticscatteringandappeara nceoftheslowmodeinadditiontothefastmodei ndynamic� scattering)�hasnotbeenobservedtodateformonot elechelicionomersolutions.�Theabsenceofhigh� concentrationcharacteristicsforthemonotelecheli cionomersolutionsgivesadditionalinsightasto� thenature� andstructureof�'heterogeneities'�insaltfreepol yelectrolytesolutions,�whichisstillcontroversia l.�

Development of SF6 gas-insulated switches that have a long service life and are highly reliable at medium voltage ratings require arc erosion of contacts in SF6 gas to be decreased. The effects of SF6 gas pressure and magnetic field for arc blow-out on erosion were studied experimentally in detail using sintered Cu-W contacts. The test current, SF6 pressure and magnetic field were 100 to 400 A, 0.1 to 0.6 MPa and 0 to 50 mT, respectively. The results show that the arc erosion rate increased linearly with the SF6 pressure. The magnetic field effectively reduced anode erosion (i.e., the application of a mere 50 mT lowered the erosion rate to 1/3 to 1/4). These phenomena may be attributed, respectively, to the increase in evaporation rate according to the shrinkage of arcing spot areas caused SF6 pressure and a decrease of the evaporation rate correlating to high-speed movement of the arcing spot on the anode by the magnetic field. However, the cathode erosion was insensitive to the magnetic field. The influence of both W grain size and composition ratio, Cu:W, on the erosion rate was also studied. The smaller W grain at Cu content of 50 to 70 wt.% was found to be best for suppression of erosion under the present conditions. Further, the increase of N2 mixture ratio to SF6 under constant total gas pressure greatly decreased contact erosion. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 118 (1): 41–51, 1997

Breakdown time lag in liquid helium is measured over a wide range of electrode sizes and pulsed electric field strengths. The breakdown time lag and dc breakdown strength are statistically analyzed by using the Weibull distribution function and weak link theory. It is found that the time lag depends on both electrical stress and the electrode surface area stressed above a critical level. It is supposed that breakdown triggering electrons are generated by field emission phenomena at small protrusion tips on the cathode surface. In higher external electric fields, a less sharper protrusion emits initial electrons with a shorter time lag and may become responsible for liquid breakdown. A theoretical equation is proposed to predict the electrode size and electrical stress dependency of the breakdown time lag, based on Fowler and Nordheim theory. It is shown that the equation is consistent with the Weibull distribution function under multiple stress of electric field and stressing time.

The effects of neutron and ion irradiations on deuterium (D) retention in tungsten (W) were investigated. Specimens of pure W were irradiated with neutrons to 0.3 dpa at around 323 K and then exposed to high-flux D plasma at 473 and 773 K. The concentration of D significantly increased by neutron irradiation and reached 0.8 at% at 473 K and 0.4 at% at 773 K. Annealing tests for the specimens irradiated with 20 MeV W ions showed that the defects which play a dominant role in the trapping at high temperature were stable at least up to 973 K, while the density decreased at temperatures equal to or above 1123 K. These observations of the thermal stability of traps and the activation energy for D detrapping examined in a previous study (≈1.8 eV) indicated that the defects which contribute predominantly to trapping at 773 K were small voids. The higher concentration of trapped D at 473 K was explained by additional contributions of weaker traps. The release of trapped D was clearly enhanced by the exposure to atomic hydrogen at 473 K, though higher temperatures are more effective for using this effect for tritium removal in fusion reactors.

The electronic and magnetic properties of Pd-TM (Fe, Co, and, Ni) alloys and their hydrides have been studied using first-principles calculations by Korringa-Kohn-Rostoke Coherent potential approximation (KKR-CPA) Green’s function method with density functional theory (DFT). The nature and the concentrations of the alloying elements and hydrogen have been examined. In addition, the magnetic properties associated with the density of states and the Fermi level in Pd-TM alloys and their hydrides are discussed. In particular, we find that the minority spin density of nickel (3d) has a sharp peak near the Fermi level. In the case of Fe and Co, the sharp peak exists above the Fermi level and this difference affects the spin polarization.

Salt-free polyelectrolyte behavior of a random ionomer, partially sulfonated polystyrene (SPS) (Na salt) having an ion content of 2.7 mol %, dissolved in a polar, aprotic solvent, dimethylformamide (DMF), is studied by dynamic light scattering. CONTIN analysis of the data indicates the existence of two diffusive modes, a fast mode and a slow mode. The diffusion coefficient of the fast mode, D f , on the order of 10 -6 (cm 2 /s), increases slightly with ionomer concentration, while the diffusion coefficient of the slow mode, D,, on the order of 10 -8 (cm 2 /s), is independent of ionomer concentration within the concentration range studied. The D f shows a negative angular dependence, while the D s shows a positive angular dependence. The fast mode may be explained in terms of the diffusion process enhanced by strong intermolecular electrostatic interactions, and the slow mode may reflect the existence of large-scale heterogeneities. These conclusions are consistent with those drawn from static (angular) light scattering data for the same system. The results obtained for salt-free ionomers in a polar organic solvent parallel those reported for salt-free polyelectrolytes in water.

The stability of ZrNi and ZrCo to heat cycles in hydrogen atmosphere was studied through changes in absorption-desorption characteristics and in crystallo-graphic structures. ZrCo easily lost its absorption-desorption capacity of hydrogen below 30 heat cycles between room temperature and a given temperature in a range of 400 ∼600 °C. X-ray diffraction analysis showed that ZrCoH3 initially formed decomposed to ZrH2+ ZrCo2. On the other hand, ZrNi was more durable than ZrCo to the similar heat cycles. But, it was found that the absorption-desorption characteristics was degraded by heat cycles over 500. The X-ray analysis showed that ZrNi also disproportionated to ZrH2 and ZrNi3. The difference in the stabilities between the two materials appears to be due to the difference in crystallographic nature upon formation of the respective hydrides.

To determine whether a dynamic cultured biograft can positively affect the function of the damaged heart.We ligated the coronary artery (LAD) of rats to generate a model of myocardial infarction (MI) and then implanted them with the following grafts comprising vascular smooth muscle cells (VSMCs) derived from the rat aorta and seeded onto biodegradable patches (patch replacement therapy; (PRTx)): control without PRTx, PRTx without seeded cells, PRTx with static cultured VSMCs, PRTx with dynamic cultured VSMCs and sham-operated. Cultured VSMCs were labeled with PKH26 for identification after implantation, and the centre of the MI site was excised and replaced with an implanted biograft. Cardiac performance was monitored for 12 weeks thereafter and followed by a histological study.Although the ejection fraction of the damaged heart improved in all groups that were transplanted with grafts, remodeling was prevented only in groups with a dynamic or static cultured patch. More cells were α-SMA-positive in the group with the dynamic, rather than the static cultured patch. Cells were positive for PKH26 in the biograft and in the infarcted myocardium.Dynamic cultured biografts improved the function of the infarcted myocardium more than statically cultured biografts or those without cells.

An alternating current magnetic susceptometer for use as a hydrogen gauge for hydrogen-storage materials was designed and developed. The experimental system can simultaneously measure the hydrogen equilibrium pressure and the magnetic susceptibility of metal hydrides. The background voltage of the susceptometer was stabilized for a long period of time, without any adjustments, by attaching an efficient compensation circuit. The performance of the susceptometer at a static hydrogen concentration was demonstrated by measuring the magnetic susceptibility of a Pd-hydrogen system under equilibrium conditions. The in situ measurement of the magnetic susceptibility of Pd during hydrogen absorption was carried out using the susceptometer. Since the in situ magnetic susceptibility obtained at a lower initial hydrogen pressure agreed with the magnetic susceptibility measured at a static hydrogen concentration, the susceptometer could be used to determine the hydrogen concentration in Pd in situ. At a higher initial hydrogen pressure, enhancement of the magnetic susceptibility was observed at the beginning of hydrogen absorption because the magnetic moments induced by the large temporary strain generated in the Pd affected the magnetic susceptibility.

Podocalyxin (PCX) is present on the apical cell membrane of podocytes and is shed in urine from injured podocytes. Urinary podocalyxin (u-PCX) is associated with severity of active glomerular injury in patients with glomerular diseases. This study examined the relationship between number of urinary podocytes, levels of u-PCX, and glomerular injury in adults with IgA nephropathy (IgAN).Urine samples voided in the morning on the day of biopsy were obtained from 51 patients with IgAN (18 men and 33 women; mean age, 31 years). All renal biopsy specimens were analyzed histologically. Pathologic variables of IgAN were analyzed per Shigematsu classification, the Oxford classification of IgAN, and the Clinical Guidelines of IgAN in Japan. Levels of u-PCX were measured by sandwich ELISA.Histologic analysis based on Shigematsu classification revealed a significant correlation between levels of u-PCX and severity of acute extracapillary abnormalities (r=0.72; P0.001), but levels of urinary protein excretion did not correlate with acute glomerular abnormalities. Levels of urinary protein excretion in patients with segmental sclerosis (n=19) were higher than in patients without (n=22) (0.49 [interquartile range (IQR), 0.20-0.88] g/g creatinine versus 0.20 [IQR, 0.10-0.33] g/g creatinine; P0.01). The number of urinary podocytes in patients with segmental sclerosis was higher than in patients without (1.05 [IQR, 0.41-1.67] per mg creatinine versus 0.28 [IQR, 0.10-0.66] per mg creatinine; P0.01).Levels of u-PCX and the number of urinary podocytes are associated with histologic abnormalities in adults with IgAN.

The salt-free polyelectrolyte behavior of random ionomers, i.e., partially sulfonated polystyrene (SPS) (Na salt: MW=400 000) having less than 5 mol % of ionic groups, dissolved in DMF0 was studied by angular light scattering measurements. At low ionomer concentration, «abnormal» Zimm plots, showing negative slopes in reciprocal reduced scattered intensity vs scattering vector curves, are observed. These effects arise because the scattering is dominated by eternal interference arising from strong electrostatic interactions between charged ionomer chains. The behavior can be explained by using general relations derived by extending the approach of Doty and Steiner

Some characteristic behavior, typically observed for salt-free polyelectrolytes in water, was observed for the first time for polystyrene (PS)-based telechelic ionomers, which have ionic groups located only at the chain ends, when dissolved in DMF. The characteristic behavior observed by both viscosity and low-angle light scattering measurements for the telechelic ionomers, especially that of the monofunctional ionomer, demonstrates an important role of intermolecular electrostatic interactions in causing the characteristic behavior of telechelic ionomers

A random ionomer, partially (less than 4 mol %) sulfonated polystyrene (SPS) (Na salt), dissolved in DMF was investigated. For high molecular weight ionomers (MW: 200 000 and 400 000), the (effective) diffusion coefficient, D eff , obtained from the methods of cumulants, increases significantly with polymer (ionomer) concentration and bends over at high ionomer concentration. The D eff increases with ion content of the ionomers at fixed polymer concentration

糸球体濾過機能や糸球体の荒廃につながる癒着や半月体の形成に重要な役割をもつ糸球体上皮細胞 (GEC) の障害を評価するために，GECに対するマーカーを用いて腎組織での免疫染色性の変化，および尿沈渣を蛍光抗体法により検討した。GECに対するマーカーはポドカリキシン，C3b Receptor，PP44に対するモノクローナル抗体を用いた。腎組織レベルではC3b Receptorが組織障害の強い腎炎で減弱しており，障害のマーカーとしての有用性が示された。尿沈渣ではポドカリキシン，次いでC3b ReceptorがCasts，Granules，Cellsの形態で検出され，GEC障害のマーカーとしての有用性が示された。GEC障害の検出率は尿ポドカリキシン，尿C3b Receptor，組織C3bRの順に高かった。実際のGEC障害の評価にはこれらを総合して考える必要がある。

Based on experimental observations and theoretical explanation of the streamer spatial extension for an inhomogeneous field gap in SF6, a new model is developed, taking into account the probability of the appearance of an efficient electron. The model, which can help one to better understand the breakdown characteristics of the impulse-steepness dependence, relates the spatial extension of the streamer corona in an inhomogeneous field gap in SF6 gas to the steepness of applied positive impulses.

Various methods have been developed to make molecular composites, including coagulation, in situ polymerization of a matrix polymer, and the addition of a rigid chain to a flexible chain in block copolymers. However, many systems eventually phase separate due to inherent immiscibility of component polymers on heating; thus, they are not appropriate for melt processing, usually necessary for large-scale production. In addition, most of the mechanical properties reported are tensile properties of fiber and film specimens. Bulk sample data are rare. This is again due to a lack of thermal consolidation without causing phase separation in many molecular composites. One promising approach to circumventing this problem is introduction of strong intermolecular interactions, such as ion–ion and ion–dipole interactions. In this article, after citing some results on mechanical properties of molecular composites based on nonionic rod-like molecules, mechanical properties of molecular composites made via ionic interactions (ion–dipole interactions) are described. Keywords: molecular composites; mechanical properties; ionic interactions; PPTA; polymer

We report the case of a 38-year-old woman diagnosed with Gitelman syndrome. A kidney biopsy showed abundant floating cells in the Bowman’s space of the mildly cystic glomeruli, moderate tubulointerstitial changes and apparent intimal thickening of small arteries. These floating cells were immunohistologically identified as podocytes, by the expression of podocalyxin, vimentin, Wilms’ tumor 1, synaptopodin and nephrin with positivities of 100 %, 88.4 %, 80.4 %, 74.7 % and 22.6 %, respectively. In these phenotypes, nephrin expression was notably decreased in both detached and capillary-attached podocytes in comparison with normal control podocytes. Immunostaining of both detached and capillary-attached podocytes for Bax, Bcl-2, desmin, fibroblast-specific protein-1, α-smooth muscle actin and Ki-67 was negative, as were TUNEL assays. These results suggest that apoptosis and epithelial−mesenchymal transition were not the main cause of podocyte detachment in this patient. In addition, levels of urinary podocalyxin were not elevated, suggesting the detached podocytes were not excreted in the urine. To the best of our knowledge, this is the first report of severe intraglomerular non-apoptotic detachment of podocytes in Gitelman syndrome. This podocyte detachment may be associated with nephron obstruction and reduced nephrin expression.

Wide-gap semiconductors with nanostructures such as nanoparticles, nanorods, nanowires are promising as a new type of UV photosensor. Recently, ZnO (zinc oxide) nanowires have been extensively investigated for electronic and optoelectronic device applications. ZnO nanowires are expected to have good UV response due to their large surface area to volume ratio, and they might enhance the performance of UV photosensors. In this paper, a new fabrication method of a UV photosensor based on ZnO nanowires using dielectrophoresis is demonstrated. Dielectrophoresis (DEP) is the electrokinetic motion of dielectrically polarized materials in non-uniform electric fields. ZnO nanowires, which were synthesized by nanoparticle-assisted pulsed-laser deposition (NAPLD) and suspended in ethanol, were trapped in the microelectrode gap where the electric field became higher. The trapped ZnO nanowires were aligned along the electric field line and bridged the electrode gap. Under UV irradiation, the conductance of the DEP-trapped ZnO nanowires exponentially increased with a time constant of a few minutes. The slow UV response of ZnO nanowires was similar to that observed with ZnO thin films and might be attributed to adsorption and photodesorption of ambient gas molecules such as O(2) or H(2)O. At higher UV intensity, the conductance response became larger. The DEP-fabricated ZnO nanowire UV photosensor could detect UV light down to 10 nW cm(-2) intensity, indicating a higher UV sensitivity than ZnO thin films or ZnO nanowires assembled by other methods.

A needle-type glucose sensor has been developed using a new type of oxygen (O 2 ) electrode system composed of a 0.5 or 1.0 mm Ti wire about 2.5 mm in diameter and 35 mm long, whose top is anodically oxidized. It responds well to O 2 tension in a saline solution. As the residual current of the prototype sensor is rather large at zero O 2 tension, the oxidized surface has been modified with Pt by electroplating. Thus the O 2 reduction preferentially proceeds on the Pt sites, and the applied potential for the sensor becomes less negative than for the prototype. Miniaturization of the sensor has been performed by using the side wall of the 0.3 mm Ti wire ≈ 1.1 mm in diameter and 15 mm long as the sensing and enzyme immobilizing site. GOD is immobilized on the Pt-modified surface of the Ti electrode with a silanizer using glutaraldehyde and BSA, or with an electropolymerized polypyrrole film. Both sensors linearly respond to glucose over a range of more than 500 mg/dl. The shape of the miniature sensor is promising for immobilizing the enzyme and coating the membranes easily.