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Background Chronic gut dysfunction occurs in up to 25% of patients following antibiotic-treated C. difficile infection (CDI). We developed a humanized mouse model in which germ free mice colonized with microbiota from patients with severe constipation post-CDI developed slow colonic transit, as a result of damage to the Interstitial Cells of Cajal (ICC) network by pro-inflammatory macrophages. Colonic transit, immune activation and the ICC network normalized after fecal microbiota transplantation using samples from healthy mice, as well after treatment with psyllium fiber. Here we explored the long-term effects of psyllium and evaluated the therapeutic potential of pectin and quercetin in this model. Purpose 1) To investigate the time course of the beneficial effect of psyllium on colonic motility. 2) To explore possible therapeutic properties of flavonoids and pectin. Method Germ-free mice were colonized with microbiota from the post-CDI (PCDI) patient or healthy controls (HC). After 3 weeks, the mice were fed for 4-5 weeks with a control diet or diets with 15% psyllium (PSY), 10% pectin (PCT) or 0.05% quercetin (QCT). To evaluate time course of PSY on motility, control diet was administered for 3-weeks following PSY treatment. The bead expulsion test was used to assess colonic motility. Stool samples were collected for microbial profiling, and short and branched-chain fatty acids (SCFA/BCFA) analysis. Macrophages morphology and counts, and ICC network structure were evaluated by immunohistochemistry. Result(s) Compared to HC microbiota, colonization with post-CDI microbiota induced slow colonic transit in recipient mice, and this was normalized by PSY (n=13; p=0.02). The benefit of PSY was transient as colonic transit slowed following discontinuation of PSY (p=0.001). The changes in colonic transit were paralleled by switch in macrophages phenotype and damage to the ICC network. Additionally, discontinuation of PSY resulted in a return of microbial diversity (p< 0.001), SCFA/BCFA levels (acetic and propionic acid/ iso-butyric and valeric acid) and specific bacterial species abundances, to values seen in untreated mice colonized with post-CDI microbiota. Microbial analysis predicted potential pathways involved in macrophage polarization, including the synthesis of SCFA/BCFA, degradation of inositol and production of acetylglucosamine. PCT also normalized slow intestinal transit in mice colonized with post-CDI microbiota (p=0.003), restored phenotype of infiltrating macrophages, and improved the structural integrity of the ICC network. In contrast, QCT failed to improve gut dysfunction in PCDI mice. Conclusion(s) Our results suggest that the beneficial effects of psyllium in this model are transient. Dietary pectin, but not quercetin, may also serve as a novel treatment strategy to restore colonic motility and immune homeostasis in humans with severe constipation post-CDI. Please acknowledge all funding agencies by checking the applicable boxes below Other Please indicate your source of funding; W. Garfield Weston Foundation Disclosure of Interest None Declared

Background Although intestinal muscle layer macrophages have been suggested to play an important role in the colonic transit by interacting with the myenteric plexus neurons, they have not been fully characterized. CD64 (FcγRI) is one of the most generally used markers for intestinal macrophages, but several studies suggested existence of a subpopulation of macrophages that lack CD64. In addition, the muscle layer macrophage subsets currently identified are considered to be same in the small intestine and colon, although this has not been formally tested. Purpose In this study, we aim to identify and characterize the subsets of muscle layer macrophages by CD64 marker. We hypothesize that colon specific CD64-macrophages have a different role from CD64+ conventional macrophages. Method The muscle layers of small intestine (ileum) and colon were separated from SPF mice and cells from each muscle layer were analyzed by flow cytometry and fluorescent staining. The muscle layer macrophages were gated withCD45+, F4/80+, CD11b+ and Ly6c-, and analyzed with CD64 and MHCⅡmarkers by flow cytometry. In additional experiments, fluorescent staining with CD64 and F4/80 was assessed in whole-mount tissue of the separated muscle layer. Result(s) Within the macrophage population from the colon muscle layer, we found not only CD64+ cells, a conventional marker of macrophage, but also CD64- cell population (CD45+, F4/80+, CD11b+, Ly6c-). However, in the small intestine, this CD64- cell population was barely detectable. In addition, colonic CD64+ cells had mostly high expression of MHCⅡ marker, while CD64- cells had low expression of MHCⅡ. A similar pattern was found when we examined intestinal and colonic tissues by immunofluorescent staining. Conclusion(s) We identified a colon-specific CD64- subset of macrophage in muscle layer. Additional experiments are needed to characterize their immunomodulatory properties. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared CLIINICAL PRACTICE

Kinetics of decay of polaron pairs as precursors of free charge carriers at photoexcitation of poly(3-octylthiophene) under applied electrical field have been observed directly within a picosecond time domain by using the two-correlated-pulse laser technique. Experiments have shown that polaron pairs were generated without any noticeable delay after the light absorption. At high enough excitation intensity, free charge carriers have been shown to take part in the second-order processes photocurrent produced by the recombination of two neighboring polaron pairs. It has been clarified that polaron pairs with two kinds of lifetime τ fast , τ delay exists, and τ delay decreases by high electrical field strength, and that polaron pair is the main origin of the second-order photocurrent. The direct observation of photoluminescence within a picosecond time domain has been also discussed.

Photovoltaic properties of a photovoltaic cell with a structure of indium-tin-oxide (ITO)/C 60 /conducting polymer (CP)/Au have been investigated. The C 60 /CP heterojunction in the photovoltaic cell was fabricated by spin-coating the solution of CP onto the C 60 thin film formed on ITO. Fabricated by this process, the photovoltaic cell has demonstrated the high efficiency for solar cells based on CPs. From the optical properties of C 60 /CP heterojunction and the direct surface observation by using scanning electron microscope and atmic force microscope, it has been clarified that the interpenetrating interface of C 60 and CP contributes to the high photovoltaic performance.

We have studied optical and electric properties of conducting polymers with heteroatoms such as Si and Sn in main chains. Heteroatoms, which are the same group with carbon atom, in each monomer unit of polymer main chains, are expected to possess unique characteristics and functionalities. The strong photoluminescence (PL) with high quantum efficiency and electroluminescence have been clarified, and these polymers have been exhibited the excellent optical properties and spectral narrowing. We also demonstrated pulsed, photopumped multimode laser emission from cylindrical microcavities formed by the polymer thin films deposited around optical fibers and the polymer microdisks. The bright blue laser emission could be observed.

Periodic multilayer structures of poly( p -phenylenevinylene)s have been fabricated by a self-assembly method on quartz or indium-tin- oxide-coated glass substrates. Alternating multilayers consisting of poly( P -phenylenevinylene) (PPV) and PPV derivatives which possess polyanion properties were adsorbed onto positively charged substrates. Periodic multilayers with a microdisk geometry have also been fabricated on quartz or indium-tin-oxide-coated glass substrates, and the optical properties and a yellow electroluminescence from a light- emitting device with a microdisk geometry have been studied.

Picosecond time-resolved measurements utilizing a two-correlated-pulses technique have been applied for studying the temperature and electrical field strength dependences of second-order process re...

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Y. Yoshida, Y. Nishihara, A. Fujii, M. Ozaki, K. Yoshino, H. K. Kim and N. S. Baek, S. K. Choi, Journal of Applied Physics 95, 4193 (2004) and may be found at https://doi.org/10.1063/1.1667272., Optical properties of conducting polymers with Sn atoms in main chains, such as optical absorption, photoluminescence (PL), and electroluminescence, have been studied. The electronic energy structures have been determined by optical and electrochemical measurements. Strong PL with high quantum efficiency has been clarified in the films, and photopumped multimode laser emission was demonstrated from cylindrical microcavities formed by these polymers coated around optical fibers.

The free-volume, of size ranging from 0.2 to 0.4 nm in radius, in an ethylene-vinyl alcohol copolymer was estimated using positronium lifetime measurement to elucidate the dependence of oxygen permeability on the free-volume size and fraction, on the ethylene content and on the crystallinity. The permeability and the free-volume fraction with varying the ethylene content were well related and the relation was interpreted based on the free-volume theory near below and above the glass transition temperature. On the other hand, the crystallinity significantly influenced the fraction of the amorphous region, where the free-volume hole exists, along with a slight change of the free-volume size. The variation of the permeability with the crystalline degree cannot be explained from the averaged free-volume fraction estimated by the whole volume of the polymer, but the permeability correlated with the free-volume size apparently.

Weinvestigatethemechanismsofdefectformationandopticalabsorptioninducedbyionimplantation,forfab-rication of optical devices by radiation effects. High-purity silica implanted by H þ or He 2þ was characterized usingvacuum-ultraviolet spectroscopy and electron-spin-resonance measurement. Defect formation is suppressed by OHgroups,possiblybythereleaseofatomichydrogen.TheE 0 centerandnonbridgingoxygenholecenterwerecreatedthroughpairgenerationfromthenormalSiAOASibond.TheperoxyradicalwasgeneratedthroughthereactionoftheE 0 center with interstitial oxygen, which is a Frenkel-defect pair with an oxygen vacancy. By the Kramers–Kroniganalysis on the MeV-ion implantation-induced defects, a refractive index increase of the order of 10 4 was esti-mated. 2002ElsevierScienceB.V.Allrightsreserved. Keywords:Silicaglass;Ionimplantation;Vacuumultraviolet;Electronspinresonance 1. IntroductionFabrication of optical devices such as opticalfibergratingshasbeenreportedbyourgroupus-ing mega-electron-volt-order ion implantation onsilica-coreopticalfibers[1].Inordertoextendthistechniqueforthefabricationofsilica-basedplanaroptical devices, it is important to understand themechanismsbywhichchangesinopticalpropertiessuch as refractive index are induced by the im-plantedions.Attentionisfocusedontheelectronicstopping energy loss, since it accounts for morethan 99% of the total loss and most defects areinducedthroughthisprocessinthecaseofMeV-orderionimplantation.2. Experimental proceduresSamplesaretwotypesofhigh-puritysilicaglas-ses containing different OH contents, EDC (OHcontent

Radiation effects induced by ion microbeam were studied by a confocal microspectroscopy and an atomic force microscopy (AFM). We investigate two significant radiation effects, defect generation and compaction, which were ascribed to electronic (Eelec) and nuclear stopping powers (Enucl), respectively. Photoluminescence mapping of nonbridging oxygen hole centers at 650 nm reveals the defect formation along the tracks of ions. The surface deformation measured by AFM depends on the width of irradiated by microbeam. Confinement effects from the interface of irradiated and nonirradiated regions are taken into account for the understanding of the correlation between the surface deformations and internal compactions.

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Y. Yoshida, Y. Nishihara, R. Ootake, A. Fujii, M. Ozaki, and K. Yoshino, Journal of Applied Physics 90, 6061 (2001) and may be found at https://doi.org/10.1063/1.1416863., Optical properties of conducting polymers with Si atoms in main chains, such as optical absorption, photoluminescence (PL), and electroluminescence (EL), have been studied. The electronic energy structures have been determined by optical and electrochemical measurements. The strong PL with high quantum efficiency has been clarified, and spectral narrowing has been observed by pulse excitation of a nitrogen laser. Intense blue or red EL has also been demonstrated and the emission efficiency has been improved by anode surface modification and annealing.

FeWO4 is an antiferromagnet with TN= 70 K. A Mossbauer spectroscopy measurement shows that the hyper-fine field is 41.2 kOe at 4.2 K. This small hyper-fine field suggests that a large orbital current which is induced by the spin-orbit interaction, cancels a large part of the magnetic field caused by electron spins. From the fact that most of the hyper-fine fields in Fe2+ high-spin compounds have values smaller than those expected from S = 2, we have to consider the effect of orbital magnetic current.

An anomaly in the magnetization vs. field relation has been investigated for a pristine and a stage-I iodine intercalated Bi 2 Sr 2 CaCu 2 O 8 single crystal. Although the magnetization anomaly is clearly observed for pristine Bi 2 Sr 2 CaCu 2 O 8 between 20 and 40 K, it almost disappears with the iodine intercalation. The change in the magnetization anomaly due to the iodine intercalation is discussed in terms of the dimensional crossover in the pinning mechanism and the enhancement of interlayer coupling along the c -axis.

The size distribution of free-volume (

We present the measured resistivity, Hall coefficient, and magnetization for three kinds of Bi 2 Sr 2 CaCu 2 O 8+∂ ceramics subjected to various heat treatments. The Hall effect shows that in this system the carriers have hole-like characteristics. The hole density varies according to the heat treatment; the hole density increases and T c decreases as a result of oxidation. In spite of the atmosphere in which heat treatments were performed, the flux pinning density is increased by quenching. The Hall mobility is independent of the heat treatment of Bi 2 Sr 2 CaCu 2 O 8+∂ . This result indicates that oxygen atoms enter and leave sites on planes other than the CuO 2 planes in Bi 2 Sr 2 CaCu 2 O 8+∂ .

The flux density distributions of Bi2Sr2CaCu2O8+δ single crystals were observed in the flux penetration process by a magneto-optical method using iron garnet films. For specimens with thicknesses of more than 100μm. homogeneous flux penetration was observed. The flux penetration of specimens with thicknesses of less than 30μm was inhomogeneous. This inhomogeneity was caused by the crack, the low angle grain boundary, and so on. In the specimens with thicknesses of less than 30μm. it was difficult to obtain areas larger than 2 × 2 mm2 with homogeneous flux penetration. We constructed the image processing system, calculated the value of the flux density by using the system and the value of the critical current density from the flux density distribution.

Absorption spectra, fluorescence spectra and photoconduction characteristics in thin films of polyacetylene (PA) derivatives such as monosubstituted PAs and disubstituted PAs have been studied. In disubstituted PAs, intense fluorescence is observed with Stokes shift from the absorption edge and photocurrent is observed at around the absorption edge. On the other hand, in monosubstituted PAs, photocurrent is observed at a much shorter wavelength than the absorption edge, but photoluminescence (PL) in the film is negligible. In the solution of monosubstituted PAs, weak fluorescence is observed at a shorter wavelength than the absorption edge. These differences in fluorescence and carrier generation processes have been discussed by taking the differences of the electronic states between monosubstituted PAs and disubstituted PAs into consideration.

We present the measured resistivity, Hall coefficient, and magnetization in three kinds of Bi2Sr2CaCu2O8+δ ceramics subjected to various heat treatments. The Hall effect shows that the carriers have the hole characteristic in this system. The hole number varies according to the heat treament. It increases and Tc decreases as a result of oxidation. In spite of the atmosphere of the heat treatment, the density of the flux pinning is increased by quenching. The Hall mobility is independent of the heat treatments for Bi2Sr2CaCu2O8+δ This result indicates that oxygens enter and leave sites on a plain other than the CuO2 plain in Bi2Sr2CaCu2O8+δ.

The effects of Ce doping and reduction on the superconductivity and electronic state of Nd 2-x Ce x CuO 4-∂ were investigated through measurements of the magnetization and X-ray absorption near-edge structure of the Cu-K edge of specimens annealed at various oxygen pressures and temperatures. The superconduction onset temperature and diamagnetism reach a peak at a Ce content of x=0.15. We found that the d electron density as estimated from the edge shift of the Cu-K edge absorption also has a peak around x=0.15. In addition, the d electron density increases with increasing reduction of the sample, and the magnitude of the superconduction diamagnetism becomes constant above a certain level of reduction. It is concluded that a d electron density above a certain critical value is necessary for the occurrence of superconduction in this system.

We studied the turn-off transient behavior of electron- and proton-irradiated silicon p–n junction diodes. Electron-irradiated n+–p diodes showed transient current peaks at lower reverse voltages. When the forward current was increased, the height and the number of the peaks increased, and at each peak the diode voltage showed a sharp decrease. We explain that the increased ionization coefficients by the electron irradiation caused the current peak to appear during the turn-off transients. p+–n diodes irradiated under the same condition did not show the large peak. This suggests that only the defects in the p-type silicon are responsible for the current peaks.

Low-temperature electronic states in SrRu_{1-x}Mn_xO_3 for x = 0.4, gamma approaches to ~ 5 mJ/K^2 mol or less, where the antiferromagnetic order with an insulating feature in resistivity is generated. We suggest from these results that both disorder and reconstruction of the electronic states induced by doping Mn are coupled with the magnetic ground states and transport properties., 4 pages, 2 figures, submitted to the proceedings of ICM2009 (Karlsruhe)

Mossbauer measurements in applied fields up to 13.5 T on Sc 0.25 Ti 0.75 Fe 2 are reported. The hysteretic behaviour observed in the field dependence of the bulk magnetization is also visible in the Mossbauer spectra, but hysteresis in the hyperfine fields is only found for Fe on 6h sites. In low external fields the hyperfine fields on these sites form a cone (opening angle ≈140°) with the resulting field parallel to those of 2a sites. At high fields the cone angle drops to zero and all hyperfine fields are antiparallel to the applied field. The field induced phase transition can be described as a transition from canted ferromagnetism to ferromagnetism of the Fe atoms occupying the 6h positions.

The magnetic and magnetooptical properties of Fe/V compositionally modulated multilayer films (CMFs) prepared by rf sputtering were investigated. The crystallinity and periodicity of the Fe/V CMFs were inferior to those of Co/Pt, Fe/Pt, Co/Au and Fe/Au CMFs. The saturation magnetization (M s ) decreases rapidly with decreasing modulation length (D) below approximately 50 A. Enhancement of the polar Kerr rotation angle (? K ) such as appeared in Co/Pt and Fe/Cu CMFs was not observed. The shape of the ? K spectra is similar to the spectrum of Fe film, and shows no change even when D and the thickness ratio of Fe/V are varied. Moreover, the calculated ? K spectra are in good agreement with experimental results. This suggests that the interface layers in Fe/V CMF contribute insignificantly to the polar Kerr effect.

The temperature dependences of the magnetization and magnetic anisotropy of Fe/Pt compositionally modulated multilayer films (CMFs) prepared by rf sputtering were investigated. The magnitude of the surface magnetic anisotropy K s of Fe/Pt CMFs is nearly equal to that of Co/Pt CMFs at 77K and at room temperature. The absolute value of the volume magnetic anisotropy K v of Fe/Pt CMFs is about twice as large as that of Co/Pt CMFs. The K s obtained from CMFs with thick Fe layers seems to remain nearly constant as the temperature is varied. However, K v decreases gradually with increasing temperature in the case of Fe/Pt CMFs. The relation between the saturation magnetization M s (T) and the perpendicular magnetic anisotropy K ? (T) are discussed.

Viscoelactic response of a titin single molecule chain during the course of forced unraveling was studied using atomic force microscopy. Effect of transition to/from an unfolding intermediate onto the measured elasticity data was analyzed. The result hinted that emergence of the transition onto the elasticity depends on the experimental condition such as modulation force amplitude. Anomalous slow unraveling of one domain was observed and its viscoelastic response was discussed from the viewpoint of internal friction of polymer.

The magneto-optical and magnetic properties of Co/Ag and Fe/Ag compositionally modulated multilayer films (CMF's) were investigated. Co/Ag CMF's have better crystallinity and periodicity than Fe/Ag CMF's. An enhancement of ? K was also observed at the plasma edge of Ag metal in Co/Ag and Fe/Ag CMF's. The peak values of ? K in Co/Ag CMF's are larger than those in Fe/Ag CMF's. Moreover, the enhancement of ? K due to plasma resonance at the granularly crystallized grain boundary of Co and Ag was observed in heat-treated Co/Ag CMF's. A magnetic perpendicular anisotropy K u was induced in both CMF's when the modulation length D was decreased.

The linear and non-linear ac-susceptibilities of the Mott insulator YVO3 were measured using a Hartshorn mutual inductance bridge. It is found by the temperature dependence of ac-susceptibilities that there are two magnetic phase transitions at 72.1 and 112.0 K. Above 112K, the values of linear and non-linear susceptibilities qualitatively consist with the result of the mean-field theory. It is verified that there is a power-law dependence between linear and non-linear susceptibilities, which is predicted by the mean-field theory.

The magnetic properties of an itinerant ferromagnet SrRuO3 have been determined in the hydrostatic pressure, temperature and magnetic field range 0-13.2 kbar, 4.2-300 K, and 0-90 kOe, respectively. The pressure derivatives of the Curie temperature and saturation magnetization at 4.2 K are found to be -0.67 K/kbar and -0.47 emu/g kbar, respectively

The pressure dependence of Tc of superconducting PrBa2Cu3Ox was studied by electrical resistance measurements under hydrostatic pressure up to 10 GPa. A large positive pressure coefficient of Tc, dTc/dP, with a maximum of 7. 3K/GPa, was observed. The coefficient was found to vary with the oxygen content of the compounds, in a similar manner as the isostructural YBa2Cu3Ox compound behaves. The present research revealed an opposite pressure effect on Tc with those reported for the Pr-substituted Y-Ba-Cu-O compounds with high Pr concentration.

The magnetic susceptibility and electrical resistivity in the metal-insulator (MI) transition of a mixed-valent Ti-oxide system, Y1-x CaxRTiO3, is investigated as a function of pressure. This system exhibits obviously the temperatureinduced MI transition at x=0. 3-0. 4. At the low temperature metallic phase, susceptibility, X (T), is strongly suppressed with pressure. On the other hand, in the high temperature semiconductiong phase X (T) obeying the Curie-Weiss law is not affected strongly with pressure. The coefficient of the T2-term in resistivity, A, and the residual resistivity, ρ (0), are decreases rapidly with pressure. At x=0. 375 and 0. 39, we recognize the relation of A∝X (10 K) 2 at the low temperature metallic state.

To identify the role of mucus core protein (MUC) in intrahepatic cholangiocarcinoma (ICC).We examined the expression profile of MUC2, MUC5AC and MUC6 by immunohistochemical staining in 100 ICCs and compared the clinicopathological factors and the immunohistochemical results. The expression frequency was: MUC2, 9%; MUC5AC, 40%; and MUC6, 21%. According to the gastric mucin expression profile, ICCs were classified into the following groups: null type (n = 43), gastric foveolar type (n = 36), pyloric gland type (n = 11) and gastric combined type (n = 10). Half of the gastric foveolar type and the gastric combined type were located in the hilar region, but the other types were predominant at the periphery (P = 0.0004). Well-differentiated components were more often detected in the gastric combined type and the pyloric gland type (P = 0.0281). The gastric foveolar type was associated with a higher incidence of lymph node metastasis (P0.0001). The pyloric gland type was associated with better survival and the gastric foveolar type was associated with worse survival. The gastric mucin phenotype was an independent prognostic factor by multivariate survival analysis.The gastric foveolar type of ICC was more often associated with aggressive tumour development, whereas the pyloric gland type exhibited less aggressive behaviour.

We have studied bulk vortex properties in ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$ (BSCCO) using transport measurements with a unique Corbino disk contact geometry. This Corbino disk contact geometry allows us to measure true bulk vortex properties free from surface barrier effects. The investigated vortex properties include current-induced vortex dissipation in the vortex liquid and vortex solid phases, vortex matter phase transition (vortex lattice melting transition), and vortex correlation along the $c$ axis of BSCCO. No discrepancy is found between our measurements and others measurements using the conventional four-probe contact geometry, which renders vortex transport properties susceptible to the Bean-Livingston surface barrier effect. We conclude that the sample bulk vortex matter properties determine the vortex transport behaviors in BSCCO.

The metal-insulator transition in the Y 1− x Ca x TiO 3 alloy system occurs about x = 0.35. Various physical property measurements suggest that this MI transition cannot be understood as a simple change in the carrier number in the Hubbard band. In this paper, detailed magnetic property and electrical resistivity behaviours around MI transition are discussed.

We present a detailed angle-resolved photoemission study on the layered transition-metal dichalcogenide 1T-TaS1.2Se0.8 in the commensurate charge-density-wave (CDW) phase. A drastic reduction in the spectral weight along the high symmetry line GammaM, particularly around the point M, is observed when s-polarized light was used. This implies that the initial state must be symmetric with respect to a mirror plane perpendicular to the line GammaK, which is consistent with conventional band calculations in the absence of the CDW. We conclude that there is only a limited amount of modification of the electronic structure of 1T-TaS1.2Se0.8 in the commensurate CDW phase due to the CDW-related potential.

Electrical properties such as electrical conductivity and dielectric property; optical properties such as photoconductivity and photoluminescence and mechanical properties such as viscosity of conducting polymers including polythiophene, poly(p-phenylenevinylene) and polyacetylene derivatives in liquids, that is, in solution and fused liquid state have been studied as functions of the molecular structure and temperature. These properties in these substituted derivatives, were strongly dependent on the substituent, and changed drastically at the melting point, which has been discussed by taking the conformation of the substituents and inter polymer main chain interactions into consideration. Electrorheological effects in conducting polymer solutions has also been studied and was found to be dependent on both molecular structures and temperature, which can be also interpreted in terms of molecular reorientation and changes of molecular conformation and interchain interaction.

In this paper, we report the difference in absorption spectrum that has a close relation to photosensitivity and the improvement of the quality by thermal annealing between two Ge-doped SiO/sub 2/ planar waveguides synthesized by different methods.

Lifetime control in silicon power devices is required to reduce turn-off time and energy loss during switching. High energy (2 MeV range) electron and proton irradiations have been used for this purpose. We developed a new method of introducing defects by using low energy (270 keV) electron irradiation and hydrogen annealing. It was generally considered that 270 keV energy electrons are not strong enough to introduce defects. It is thought that the silicon knocked out by a low energy electron stays around the vacancy, and that the silicon can come back to the vacancy very easily. However, if the defect is filled by some other atom, such as hydrogen, the knocked-out silicon can not come back easily, and a higher and more stable defect concentration can be expected. This is why we used hydrogen annealing after low energy electron irradiation. We annealed the irradiated diodes in nitrogen or hydrogen atmosphere. The diodes annealed in hydrogen showed a significant lifetime reduction. This was manifested by increase in forward diode voltage, and decrease in turn-off charge.

Objective We audited the use of intrapartum intravenous antibiotics in mothers who were Group B Streptococcus (GBS) positive in their current pregnancy, and compared the neonatal management and outcomes in those who received adequate, and inadequate antibiotic cover. Method All deliveries logged between 1st October–31st December 2012 were crosschecked with maternal microbiology results to identify those GBS positive in their current pregnancy. We then audited whether these women were given adequate antibiotic cover in labour (at least 1 dose 4 h before delivery) as per local guidelines. Subsequent neonatal outcomes and length of hospital stay was analysed. Results Total live births were 1185 babies from 1166 mothers, 131 (11%) women were GBS positive and 111 (9%) required intrapartum antibiotics as per protocol. Of which 43 (39%) received no antibiotics, 17 (15%) were inadequately covered and 51 (46%) had adequate intrapartum antibiotic cover. Most common reason for no/inadequate antibiotic cover was too quick delivery, followed by GBS microbiology results that were not acted upon, or not available in time. Other reasons included emergency caesarean section, home births, and maternal refusal. Of the total 135 babies born to mothers with GBS, 55 (41%) started IV antibiotic treatment, 41 (75%) of these because the mother was inadequately covered in labour. There was one GBS positive neonatal blood culture. Average length of stay for babies whose mothers received adequate antibiotics (and only required 12 h of observations) was 1.6 days. However, for babies who required IV antibiotics because of inadequate intrapartum antibiotics, the average length of stay was significantly longer at 4.2 days. Conclusion The results demonstrate that over half of women who require intrapartum antibiotics were receiving no, or inadequate antibiotic cover. This not only has implications for postnatal antibiotic use, but also for patient satisfaction, hospital bed availability and costs. Intrapartum antibiotic use in GBS needs to improve, and we suggest this can be achieved by reinforcing patient education so GBS positive women present to labour ward earlier. Also, we must ensure GBS positive swab results are not missed.

We examined the effects of Ca doping PrBa2-xCaxCu3Oy (x=0~0.7) and Ag doping PrBa2Cu3-xAgxOy(x=0~0.3) on the structural, electrical and magnetic properties. Rietveld refinement of powder x-ray diffraction data indicated that both doped systems have a tendency to become a tetragonal structure even after the oxygen annealing. The c-axis lattice parameters of PrBa2-xCaxCu3Oy (x=0~0.7) decreased, and conductivity increased with increase of the Ca doping concentration. The c-axis lattice parameter of PrBa2Cu3-xAgxOy(x=0~0.3) increased, and conductivity did not change with increase of the Ag doping concentration.

High strength polyethylene fiber (Dyneema®fiber: hereinafter abbreviated to DF) has a large negative thermal expansion coefficient (TEC). Several kinds of fibers having differrent modulus from 15 to 134 GPa were prepared. The TEC of these fibers and fiber reinforced plastics (DFRPs) have been measured. TEC got more negative with increasing moduli of fibers, changed markedly between 15 and 51 GPa. The TEC of these FRPs shows positive values only at 15 GPa of fiber modulus and negative one above 51 GPa.

Perpendicular magnetic anisotropy (K⊥) and related magnetic properties in Pt/Fe multilayers [compositionally modulated multilayer films (CMFs)] are investigated. It is found that Pt/Fe CMFs with about an 18‐A Pt layer and Fe layer below 5 A become perpendicularly magnetized films. Surface magnetic anisotropy (Ks) and volume anisotropy (Kv) are 0.46 erg/cm2 and about − 2 × 107 erg/cm3 at room temperature, respectively. The Ks is almost equivalent to that of Pt/Co CMFs and increases with decreasing temperature. The absolute value of Kv, however, is much larger than that of the Pt/Co system. The effective magnetic anisotropy (K⊥ eff) of [Fe(4.7 A)/Pt(18.5 A)]80 CMF changes from positive to negative at T≂200 K with decreasing temperature.

The lattice constants of Hf1-xTaxFe2 with C14 structure were measured at room temperature under pressure up to 5 GPa. The magnetic phase diagram obtained as a function of pressure was compared with that obtained as a function of Ta concentration x. It is shown that changes in lattice constants by applying pressure and /or by substituting Ta for Hf affect remarkably the magnetic phase stability, which is consistent qualitatively with a recent theoretical prediction based on the local spin density approximation.