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It is known that Cu plays an essential role in reducing the grain size of precipitated bcc Fe(Si) nanocrystallites in a nanocrystalline soft-magnetic Fe85.2Si1B9P4Cu0.8 (NANOMET®) alloys like as an Fe73.5Si13.5B9Nb3Cu1 (FINEMET®). However, significant differences are there between two alloys; NANOMET has much higher iron content (~85%) than FINEMET (73.5%) and the former contains P instead of Nb for the latter. In the present work, the local structure around Cu in FINEMET was measured by X-ray absorption fine structure (XAFS) at 20K and compared with those of NANOMET during nanocrystallization. Definite differences between NANOMET and FINEMET are found in the way of the evolution of Cu clusters during nanocrystallization. In FINEMET, an fcc structure of Cu is recognized in an as-quenched ribbon indicating existence of a small number of Cu clusters or a very small size of Cu clusters which is stable up to 450 °C, while the fcc Cu clusters are developed rapidly above 450 °C. An fcc structure of the Cu clusters in FINEMET is retained all the way to the end of the nanocrystallization. On the contrary, for NANOMET the local structure around Cu changes in a sequence as "amorphous→fcc→bcc→fcc" by annealing. The reasons of such different behaviors of the local structure around Cu during nanocrystallization are discussed in terms of different contributions of Cu clusters in bcc Fe precipitation between FINEMET and NANOMET. A significantly fast crystallization process with an extraordinary large heat release can be another reason for the transition of the local structure around Cu from fcc to bcc for NANOMET. [ABSTRACT FROM AUTHOR]

Anharmonicity in grain boundary (GB) energies for Al is elucidated by employing a thermodynamic integration method with a high-accuracy artificial-neural-network potential. Symmetric tilt GBs with the [ 001 ] and [ 1 1 ¯ 0 ] rotational axes are examined. It is found that anharmonic components tend to be small at low temperatures and increasingly contribute to reduction of GB free energies at elevated temperatures. The magnitude of anharmonicity is roughly correlated with excess volume at GBs. This is presumably because GB atoms tend to have longer bond lengths than the bulk atom, and hence the inclination of the potential energy surface at GBs is more moderate than in the bulk. On the other hand, the Σ13(510) GB takes non-negligible values of the anharmonic component even at intermediate temperatures. This GB contains a distinct atom around which the potential-energy curve significantly deviates from that of the harmonic approximation. Similar trends are also observed for other [ 001 ] GBs. This is special type of abstract that is so short and could be inserted after main abstract of article, as a blurb or inserted as annotations into a Table of contents. [Display omitted] [ABSTRACT FROM AUTHOR]

Presents a study which examined low-temperature thermal conduction in particle-dispersed polyethylene. Experimental method; Results; Analyses and discussion.

Anchorage of pedicle screw instrumentation in the elderly spine with poor bone quality remains challenging. In this study, micro finite element (µFE) models were used to assess the specific influence of screw design and the relative contribution of local bone density to fixation mechanics. These were created from micro computer tomography (µCT) scans of vertebras implanted with two types of pedicle screws, including a full region-or-interest of 10 mm radius around each screw, as well as submodels for the pedicle and inner trabecular bone of the vertebral body. The local bone volume fraction (BV/TV) calculated from the µCT scans around different regions of the screw (pedicle, inner trabecular region of the vertebral body) were then related to the predicted stiffness in simulated pull-out tests as well as to the experimental pull-out and torsional fixation properties mechanically measured on the corresponding specimens. Results show that predicted stiffness correlated excellently with experimental pull-out strength (R 2  > 0.92, p < .043), better than regional BV/TV alone (R2 = 0.79, p = .003). They also show that correlations between fixation properties and BV/TV were increased when accounting only for the pedicle zone (R 2  = 0.66–0.94, p ≤  .032), but with weaker correlations for torsional loads (R 2  < 0.10). Our analyses highlight the role of local density in the pedicle zone on the fixation stiffness and strength of pedicle screws when pull-out loads are involved, but that local apparent bone density alone may not be sufficient to explain resistance in torsion. [ABSTRACT FROM AUTHOR]

Observations have recently shown that supernovae are efficient dust factories, as predicted for a long time by theoretical models. The rapid evolution of their stellar progenitors combined with their efficiency in precipitating refractory elements from the gas phase into dust grains make supernovae the major potential suppliers of dust in the early Universe, where more conventional sources like Asymptotic Giant Branch (AGB) stars did not have time to evolve. However, dust yields inferred from observations of young supernovae or derived from models do not reflect the net amount of supernova-condensed dust able to be expelled from the remnants and reach the interstellar medium. The cavity where the dust is formed and initially resides is crossed by the high velocity reverse shock which is generated by the pressure of the circumstellar material shocked by the expanding supernova blast wave. Depending on grain composition and initial size, processing by the reverse shock may lead to substantial dust erosion and even complete destruction. The goal of this review is to present the state of the art about processing and survival of dust inside supernova remnants, in terms of theoretical modelling and comparison to observations. [ABSTRACT FROM AUTHOR]

The local structure changes around Ga and Nb in Nd[sub 12.5]Fe[sub bal]Ga[sub 0.3]Nb[sub 0.2]B[sub 6.2] during homogenization, disproportionation, and recombination processes are studied by fluorescence XAFS in order to understand the roles of Ga and Nb on the improvement of (BH)[sub max]. Comparing the observed XAFS of the GaK edge with the calculated ones, Ga is proved to occupy preferentially the Fe(4c) site in Nd[sub 2]Fe[sub 14]B structure after homogenization and recombination, while it dissolves in α-Fe after the disproportionation. On the other hand, XAFS results of the Nb K edge does not change in the whole hydrogenation, disproportionation, desorption, and recombination process; the XAFS results of Nb indicate the formation of a stable NbFeB phase in the homogenized state. [ABSTRACT FROM AUTHOR]

We report a detailed small angle neutron scattering study on relaxor ferroelectric (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3(x= 0.30). Anisotropic diffuse scattering elongating along the <110> directions is observed in a wide temperature range 300–500 K. AtT= 500 K, the q-dependence of the scattering intensity,I(q), shows Porod's law. ForT≤ 450 K, an additional scattering appears in theQ-range below 0.1 Å−1and shows a power-law behavior. The power law behavior is discussed in terms of a fractal correlation of polar-nano-regions. [ABSTRACT FROM AUTHOR]

• TbCu 7 -type phase crystallized in annealed ribbons. • Coercivity of annealed ribbons increased with longer annealing time and cooling time. • A maximum coercivity of 695 kA⋅m−1 was obtained with the proper Sm composition and annealing conditions. • Nb and B became enriched at grain boundaries and the compositions of both elements increased with increasing annealing time. • Bonded magnet fabricated from Sm-Fe-Co-Nb-B melt-spun ribbons exhibited good magnetic properties and small temperature coefficient of remanence and coercivity. The effects of annealing conditions on magnetic properties, phase, and microstructural changes in Sm-Fe-Co-Nb-B melt-spun ribbons were investigated, and the dependence of magnetic properties on Sm and B composition was also investigated. Sm x Fe 80.9−(x+y) Co 16.4 Nb 2.7 B y amorphous ribbons were prepared by melt-spinning and then annealing. After annealing at 625 °C, the Sm 6.2 Fe 66.4 Co 16.4 Nb 2.7 B 8.3 ribbons exhibited crystallization of hard-magnetic TbCu 7 -type phase, and the coercivity increased as the annealing time was increased to 9 h. The grain size of the TbCu 7 -type phase as estimated from transmission electron microscopy (TEM) images was 20–50 nm for ribbons annealed for 9 h. Three-dimensional atom probe (3DAP) analysis revealed that Nb and B became enriched at grain boundaries and tended to condense at the grain boundaries with increasing annealing time. Non-magnetic Nb and B enrichment at the grain boundaries in fine TbCu 7 -type grains thus promotes magnetic decoupling between TbCu 7 -type phases and suppresses domain wall propagation, resulting in high coercivity. Composition dependence on magnetic properties was investigated. Optimum annealing time tended to increase with increasing Sm content. The Sm 6.7 Fe 65.9 Co 16.4 Nb 2.7 B 8.3 ribbons exhibited a maximum coercivity of 695 kA⋅m−1 by annealing at 625 °C for 21 h and subsequent slow cooling at a cooling rate of 4 °C⋅h−1. As B content decreased, coercivity decreased and remanence increased. The Sm 6.2 Fe 68.7 Co 16.4 Nb 2.7 B 6.0 ribbons exhibited a high σ r of 100 A⋅m2⋅kg−1 and moderate H cJ of 540 kA⋅m−1 after optimal annealing. An isotropic bonded magnet was fabricated from this ribbon. The bonded magnet exhibited high magnetic properties of B r = 0.82 T, H cJ = 538 kA⋅m−1, and (BH) max = 98 kJ⋅m−3, and small temperature coefficients of α (B r) = −0.06%⋅°C−1 and β (H cJ) = −0.27%⋅°C−1. [ABSTRACT FROM AUTHOR]

It is yet well understood how mass-loss rates from evolved stars depend on metallicities. With a half of the solar metallicity and the distance of only 50 kpc, the evolved stars of the Large Magellanic Cloud (LMC) are an ideal target for studying mass loss at low metallicity. We have obtained spectra of red-supergiants in the LMC, using the Hershel Space Observatory, detecting CO thermal lines fro J=6-5 up to 15-14 lines. Modelling CO lines with non-LTE Radiative transfer code suggests that CO lines intensities can be well explained with high gas-to-dust ratio, with no obvious reduction in mass-loss rate at the LMC. We conclude that the luminosities of the stars are dominant factors on mass-loss rates, rather than the metallicity. [ABSTRACT FROM AUTHOR]

Neutron-scattering studies of (Bi1/2Na1/2)TiO3 (BNT) have been performed to elucidate the microscopic mechanism of the broad maximum in the temperature dependence of the dielectric constant at Tm ~ 600 K and the reduction in the piezoelectric properties above the depolarization temperature, 460 ~ 480 K. We observed diffuse scattering near the T point below 700 K, which competes with the superlattice peak at the M point of the tetragonal phase but coexists with the superlattice peak at the R point of the rhombohedral phase. The diffuse scattering shows an anisotropic Q shape extending along the (100) direction transverse to the scattering vector Q, which is explained by atomic shifts bridging the tetragonal and rhombohedral structures. We propose that the broad maximum in the dielectric constant is associated with a diffusive first-order transition between the competing tetragonal and rhombohedral phases. In addition, we found that the diffuse scattering is reduced for single crystals grown under high oxygen pressure, which suggests an analogy with the central peak in hydrogen-reduced SrTiO3. Inelastic neutron scattering near the Γ point reveals a heavily overdamped soft mode similar to those reported in lead-based relaxors, the "waterfall" feature. Moreover, a damped soft transverse acoustic mode is observed for the (100) direction as the anisotropic diffuse scattering, indicating phase instabilities with the same origin as that of the diffuse scattering. The recovery of the soft mode is observed near the depolarization temperature, which coincides with the disappearance of the superlattice peak at the M point. These results indicate that the depolarization and the waterfall feature originate in the dynamic nature of ferroelectric clusters in the coexisting tetragonal/rhombohedral phase. [ABSTRACT FROM AUTHOR]

Systematic inelastic neutron scattering studies have been performed on La1.85Sr0.15Cu1-yNiyO4 in order to elucidate the microscopic mechanism of magnetic Ni impurity doping effects on spin dynamics and superconductivity. In contrast to Zn doping, which precipitates static or quasistatic spin correlations around dopant, Ni doping remarkably reduces Ecomme, the minimum energy of the upward branch of the hourglass-shaped magnetic dispersion where a commensurate magnetic peak is observed. Ni doping at y ~ 0.04 further reduces Ecomme to zero energy and broadens the distribution of Ecomme, corresponding to the appearance of the normal state at base temperature (T ~ 4 K) as well as the broadening of the superconducting transition. [ABSTRACT FROM AUTHOR]

Abstract: We describe a method of white-beam inelastic neutron scattering for improved measurement efficiency. The method consists of matrix inversion and selective extraction. The former is to resolve each incident energy component from the white-beam data, and the latter eliminates contamination by elastic components, which produce strong backgrounds that otherwise obfuscate the inelastic scattering components. In this method, the optimal experimental condition to obtain high efficiency will strongly depend on the specific aim of the individual experiments. [Copyright &y& Elsevier]

In situ measurements of the X-ray absorption fine structure for the supercooled liquid state of Au65Cu10.5Si17Ag7.5 bulk metallic glass, which exhibits extraordinarily low Tg and a stable supercooled liquid state, were performed. Analyses of data combined with molecular dynamics simulation suggest that the glass transition is caused by the breakdown of Cu–Cu bonding which connects Cu-centered icosahedral clusters. Cu atoms play a key role in the enhancement of glass formability and the low Tg of the Au65Cu10.5Si17Ag7.5 bulk metallic glass. [ABSTRACT FROM AUTHOR]

ABSTRACT We develop an approximate analytical solution for the transfer of line-averaged radiation in the hydrogen recombination lines for the ionized cavity and molecular shell of a spherically symmetric planetary nebula. The scattering problem is treated as a perturbation, using a mean intensity derived from a scattering-free solution. The analytical function was fitted to Hα and Hβ data from the planetary nebula NGC 6537. The position of the maximum in the intensity profile produced consistent values for the radius of the cavity as a fraction of the radius of the dusty nebula: 0.21 for Hα and 0.20 for Hβ. Recovered optical depths were broadly consistent with observed optical extinction in the nebula, but the range of fit parameters in this case is evidence for a clumpy distribution of dust. [ABSTRACT FROM AUTHOR]

Abstract: Local structures of the hydrogenated (Ni0.6Nb0.4)1-xZrx (x=0.3–0.4) amorphous alloys attract much attention for the sake of their epoch-making electronic transport behaviors. We investigated the local structures by XAFS for the as-quenched (Ni0.6Nb0.4)0.65Zr0.35 and hydrogenated [(Ni0.6Nb0.4)0.65Zr0.35]0.922H0.078 amorphous alloys, in which ballistic conductivity has been observed. XAFS results of the Ni K-edge are analyzed based on the structure model deduced by the first principle calculation. The analysis suggests that highly distorted icosahedral Ni5Nb3Zr5 cluster, which has a centered-Ni and a surrounding Nb triangle, is a main structural unit of (Ni0.6Nb0.4)0.65Zr0.35 and the [(Ni0.6Nb0.4)0.65Zr0.35]0.922H0.078 amorphous alloys. This distorted icosahedral Ni5Nb3Zr5 cluster can be associated with the occurrence of the singular electronic transport behaviors of the hydrogenated (Ni0.6Nb0.4)0.65Zr0.35 alloy. [Copyright &y& Elsevier]

We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of about 220 times the luminosity of the Sun. The intensity and spectral energy distribution of the emission suggest a dust mass of about 0.4 to 0.7 times the mass of the Sun. The radiation must originate from the supernova ejecta and requires the efficient precipitation of all refractory material into dust. Our observations imply that supernovae can produce the large dust masses detected in young galaxies at very high redshifts. [ABSTRACT FROM AUTHOR]

In image-free navigation systems, cup orientation is determined in the pelvic coordinate by registration of bony landmarks. While the value of navigation relates primarily to the reliability and accuracy of cup placement, the reliability of registration plays a role in cup placement. We therefore examined intra- and intersurgeon variability in registration and the distance between registration points in each bony landmark. Thirty-seven THAs were performed in the lateral position and 15 THAs in the supine position. The cup was fixed using a navigation system. The registration was repeated two more times by operator and assistant, and the intra- and intersurgeon variability of cup abduction angle and anteversion was analyzed by ICC (intraclass correlation coefficients). In 25 hips, the distance between intrasurgeon registration points and between intersurgeon registration points in each landmark were calculated. The ICC in the lateral position ranged between 0.59 and 0.81, and between 0.85 and 0.95 in the supine position. The ICCs of cup abduction angle for the intra- and intersurgeon variability were 0.92 and 0.95 for the supine position and 0.65 and 0.59 for the lateral position. Those of anteversion were 0.93, 0.85, and 0.81, 0.72, respectively. The variability in locating the ASIS in the lateral position was greater than that in the supine position. The variability of registration points depended on bony landmarks and patient position but the range of variability we found would not likely result in a large variability in cup placement. [ABSTRACT FROM AUTHOR]

We report on an analysis of the gas and dust budget in the interstellar medium (ISM) of the Large Magellanic Cloud (LMC). Recent observations from the Spitzer Space Telescope enable us to study the mid-infrared dust excess of asymptotic giant branch (AGB) stars in the LMC. This is the first time we can quantitatively assess the gas and dust input from AGB stars over a complete galaxy, fully based on observations. The integrated mass-loss rate over all intermediate and high mass-loss rate carbon-rich AGB candidates in the LMC is , up to . This number could be increased up to if oxygen-rich stars are included. This is overall consistent with theoretical expectations, considering the star formation rate (SFR) when these low- and intermediate-mass stars where formed, and the initial mass functions. AGB stars are one of the most important gas sources in the LMC, with supernovae (SNe), which produces about . At the moment, the SFR exceeds the gas feedback from AGB stars and SNe in the LMC, and the current star formation depends on gas already present in the ISM. This suggests that as the gas in the ISM is exhausted, the SFR will eventually decline in the LMC, unless gas is supplied externally. Our estimates suggest ‘a missing dust-mass problem’ in the LMC, which is similarly found in high- z galaxies: the accumulated dust mass from AGB stars and possibly SNe over the dust lifetime (400–800 Myr) is significant less than the dust mass in the ISM. Another dust source is required, possibly related to star-forming regions. [ABSTRACT FROM AUTHOR]

Long-term results of resurfacing in osteonecrosis of the femoral head (ONFH) are lacking and migration of the femoral component, necrosis of the femoral head and fracture of the femoral neck or head have been depicted. The aim of this study was to analyse the bone quality and 3-dimensional microarchitecture of the femoral head and neck in patients with ONFH compared to a group of patients with primary osteoarthritis (OA). μCT was used to compare the microarchitecture of the femoral head and neck in patients with ONFH ( n = 10) and a control group of patients with primary OA ( n = 10). No statistical significant differences were found for bone volume and the bone volume fraction, the connectivity density and the structure model index in patients with ONFH and those with OA ( P > 0.05). Patients with ONFH and those with OA had a similar trabecular number, thickness and separation ( P > 0.05). Based on our findings, we might conclude that hip resurfacing arthroplasty is a possible therapeutic option in the treatment of ONFH of the young and active patient and that an insufficient bone stock in ONFH seems not to be the deciding factor for failure. However, we just focussed on one of probably various factors. Further studies are needed to support these findings. [ABSTRACT FROM AUTHOR]

The article discusses the study that looked into the optimal treatment for women with Stage IIIc endometrium cancer. It states that adjuvant treatment compared the use of chemotherapy (CT) alone against the extended-field radiotherapy (RT) plus CT. The study found that the combine RT and CT treatment resulted to a better survival rate than CT alone with reduced recurrences in pelvic malignancies.

Knots are commonly found in nearby planetary nebulae (PNe) and star-forming regions. Within PNe, knots are often found to be associated with the brightest parts of the nebulae and understanding the physics involved in knots may reveal the processes dominating in PNe. As one of the closest PNe, the Helix Nebula (NGC 7293) is an ideal target to study such small-scale (∼300 au) structures. We have obtained infrared integral spectroscopy of a comet-shaped knot in the Helix Nebula using the Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) on the Very Large Telescope at high spatial resolution (50–125 mas). With spatially resolved 2-μm spectra, we find that the H2 rotational temperature within the cometary knots is uniform. The rotational-vibrational temperature of the cometary knot (situated in the innermost region of the nebula, 2.5 arcmin away from the central star) is 1800 K, higher than the temperature seen in the outer regions (5–6 arcmin from the central star) of the nebula (900 K), suggesting that the excitation temperature varies across the nebula. The obtained intensities are reasonably well fitted with 27 km s−1 C-type shock model. This ambient gas velocity is slightly higher than the observed [He ii] wind velocity of 13 km s−1. The gas excitation can also be reproduced with a photon-dominant region (PDR) model, but this requires an order of magnitude higher ultraviolet radiation. Both models have limitations, highlighting the need for models that treat both hydrodynamical physics and the PDR. [ABSTRACT FROM AUTHOR]

We have observed five carbon-rich asymptotic giant branch (AGB) stars in the Fornax dwarf spheroidal (dSph) galaxy, using the Infrared Spectrometer on board the Spitzer Space Telescope. The stars were selected from a near-infrared survey of Fornax and include the three reddest stars, with presumably the highest mass-loss rates, in that galaxy. Such carbon stars probably belong to the intermediate-age population (2–8 Gyr old and metallicity of [Fe/H]∼−1) of Fornax. The primary aim of this paper is to investigate mass-loss rate, as a function of luminosity and metallicity, by comparing AGB stars in several galaxies with different metallicities. The spectra of three stars are fitted with a radiative transfer model. We find that mass-loss rates of these three stars are . The other two stars have mass-loss rates below . We find no evidence that these rates depend on metallicity, although we do suggest that the gas-to-dust ratio could be higher than at solar metallicity, in the range 240 to 800. The C2H2 bands are stronger at lower metallicity because of the higher C/O ratio. In contrast, the SiC fraction is reduced at low metallicity due to low silicon abundance. The total mass-loss rate from all known carbon-rich AGB stars into the interstellar medium (ISM) of this galaxy is of the order of . This is much lower than that of the dwarf irregular galaxy Wolf Lundmark Melotte (WLM), which has a similar visual luminosity and metallicity. The difference is attributed to the younger stellar population of WLM. The suppressed gas-return rate to the ISM accentuates the difference between the relatively gas-rich dwarf irregular and the gas-poor dSph galaxies. Our study will be useful to constrain gas and dust recycling processes in low-metallicity galaxies. [ABSTRACT FROM AUTHOR]

We investigate the molecular bands in carbon-rich asymptotic giant branch (AGB) stars in the Large Magellanic Cloud (LMC), using the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope ( SST) over the 5–38 μm range. All 26 low-resolution spectra show acetylene (C2H2) bands at 7 and 14 μm. The hydrogen cyanide (HCN) bands at these wavelengths are very weak or absent. This is consistent with low nitrogen abundances in the LMC. The observed 14 μm C2H2 band is reasonably reproduced by an excitation temperature of 500 K. There is no clear dilution of the 14 μm C2H2 band by circumstellar dust emission. This 14-μm band originates from molecular gas in the circumstellar envelope in these high mass-loss rate stars, in agreement with previous findings for Galactic stars. The C2H2 column density, derived from the 13.7 μm band, shows a gas mass-loss rate in the range 3 × 10−6 to 5 × 10−5 M⊙ yr−1. This is comparable with the total mass-loss rate of these stars estimated from the spectral energy distribution. Additionally, we compare the line strengths of the 13.7 μm C2H2 band of our LMC sample with those of a Galactic sample. Despite the low metallicity of the LMC, there is no clear difference in the C2H2 abundance among LMC and Galactic stars. This reflects the effect of the third dredge-up bringing self-produced carbon to the surface, leading to high carbon-to-oxygen ratio at low metallicity. [ABSTRACT FROM AUTHOR]

We present high-resolution images of the strongly bipolar planetary nebula NGC 6537, obtained with the Hubble Space Telescope ( HST) and with the infrared adaptive optics system on the Very Large Telescope. The central star is detected for the first time. Using the multiband photometry and constraints from the dynamical age of the nebula, we derive a temperature in the range , a luminosity and a core mass . The progenitor mass is probably in the range . The extinction map shows a largely symmetric, and compact dust structure, which is most likely a shell, located at the neck of the bipolar flow, only 2–4 arcsec from the star. The dust shell traces a short-lived phase of very high mass loss at the end of the asymptotic giant branch (AGB). The dynamical age of the shell and bipolar lobes are very similar but the morphologies are very different. The data suggests that the mass loss during the ejection of the compact shell was largely spherically symmetric, and the pronounced bipolarity formed afterwards. The dynamical ages of the bipolar lobes and dust shell are similar, which is consistent with suggestions that bipolar structures form in a run-away event at the very last stages of the AGB mass loss. The inner edge of the dust shell is ionized, and polycyclic aromatic hydrocarbon (PAH) emission is seen just outside the ionized gas. We associate the PAH emission with the photodissociation region of the molecular shell. [ABSTRACT FROM AUTHOR]

The butterfly-shaped planetary nebula, NGC 6302, shows a unique, dense equatorial dark lane, which is presumably a dusty disc, obscuring an unobserved, very hot central star. We trace the structure of this disc usingHubble Space TelescopeHα and[Nii] images, Very Large Telescope L-and M-band images at 0.4-arcsec resolution, including Brα and polycyclic aromatic hydrocarbon (PAH) images, and a James Clerk Maxwell Telescope 450-μm image. Extinction maps are derived from these images. Within the disc, the extinction isand. The 450-μm map shows a north–south elongated central core, tracing the massive dust disc, and extended emission from dust in the bipolar flows. A fit to the spectral energy distribution yields the disc dust mass of. The innermost region shows an ionized shell. The orientation of the polar axis shows a marked change between shell, disc and inner and outer outflow. The structures are well described by the warped-disc model of. PAH images are presented: PAH emission is found in the shell but avoids the disc. An infrared source is found close to the expected location of the central star. [ABSTRACT FROM AUTHOR]

Abstract: XAFS measurements of the La L3 and Ni K-edges for LaNi5 were done at temperatures of 20, 100, 200 and 293K. The temperature dependences of the Debye–Waller factors for La and Ni are deduced. The results show that mean square fluctuation in interatomic distance σ2 of La for LaNi5 is fairly large and the Debye temperature ΘD of La changes with temperature. These results indicate that the La atom with large atomic size changes its atomic position easily in LaNi5. The large σ2 value of A (rare earth) elements for AB5 compounds might be correlated to their high capability of the hydrogen absorption and desorption. [Copyright &y& Elsevier]

Local structures around Y and Zr solutes in bcc-Fe are studied for the melt-quenched ribbons by X-ray absorption fine structure (XAFS). The melt-quenched ribbons of Fe99Y1 and Fe99Zr1 are confirmed as a super-saturated solid solution by X-ray diffraction and DSC. XAFS results indicate that the local structures around Y and Zr for the melt-quenched Fe99Y1 and Fe99Zr1 are similar to those for the Fe-rich intermetallic compounds; Fe17Y2 for Fe99Y1 and Fe2Zr for Fe99Zr1. Prior to the apparent precipitation of the intermetallic compounds by annealing, the precursor of intermetallic compounds, about 1 nm in a diameter, are formed in the melt-quenched Fe99Y1 and Fe99Zr1. The large size mismatch of the atom between solutes (Y and Zr) and host (Fe) is responsible for it. This result shows a sharp contrast to that for the case of Cu and Ga in bcc-Fe, in which Cu and Ga occupy a substitutional site of bcc-Fe. [Copyright &y& Elsevier]

The aim of this study was to investigate the late effect on cancer mortality risk of the radiation exposure of atomic bomb survivors who comprised a study population different from that previously studied by the Radiation Effects Research Foundation (RERF). We examined survivors residing in Hiroshima Prefecture, who were followed up between 1968 and 1989 by the Research Institute for Radiation Biology and Medicine (RIRBM) at Hiroshima University. We used the doseevaluation system known as Atomic Bomb Survivors 1993 Dose (ABS93D), which was based on the Dosimetry System 1986 for the survivors registered with RERF. The dose estimation was applied in a total of 35,123 subjects. Among survivors who had been alive for 20 years after the bombing, the relative mortality risk of leukaemia at 1 Gy of organ dose was 2.37 (90% confidence interval: 1.36-3.39), which was significantly higher than the zero dose control group. Similarly, significantly higher risks were observed for all cancers except leukaemia, including cancers of the lung, colon and female breast. Comparison is made with RERF results regarding temporal changes in the relative risk. Although we observed slightly lower relative risks than RERF values for the cancer of the stomach and lung, and for all cancer except leukaemia, no marked trends for any cancer were observed in this study. Though there were some differences in population between RERF and RIRBM, no marked discrepancies were observed. [ABSTRACT FROM AUTHOR]

Daidzein and genistein, which are responsible for the objectionable flavor of soy milk, increased during the soaking of soybeans, the first step of soy milk manufacturing. The maximum production of these isoflavone compounds occurred at 50°C and at pH 6.0 depending upon the temperature and pH of the soaking water. The production of these substances was strongly inhibited by glucono-δ-lactone which was a competitive inhibitor of β-glucosidases. It would appear, therefore, that β- glucosidases were responsible for the production of daidzein and genistein during soaking. [ABSTRACT FROM AUTHOR]

Emotional and behavioural problems in primary school children were investigated with Rutter's questionnaires, in Japan (N = 2638), China (N = 2432) and Korea (N = 1975). The prevalence rates of children with deviant scores on the teachers' and parents' scales were 3.9 and 12.0% in Japan, 8.3 and 7.0% in China and 14.1 and 19.1% in Korea, respectively. Deviance of the antisocial type was more frequent than the neurotic type in Japan and China. Both types were almost equally frequent in Korea. The prevalence of deviance was higher in boys, and also higher in those children with poor school achievement. In China and Korea, the prevalence was higher in children from one-parent families. Although other family background factors had major effects on deviant behaviour in these two countries, the number of siblings and birth order had only a limited effect on the deviant behaviour of children in Japan, China and Korea. [ABSTRACT FROM AUTHOR]

Interstellar dust plays a crucial role in the evolution of galaxies. It governs the chemistry and physics of the interstellar medium. In the local universe, dust forms primarily in the ejecta from stars, but its composition and origin in galaxies at very early times remain controversial. We report observational evidence of dust forming around a carbon star in a nearby galaxy with a Low abundance of heavy elements, 25 times lower than the solar abundance. The production of dust by a carbon star in a galaxy with such primitive abundances raises the possibility that carbon stars contributed carbonaceous dust in the early universe. [ABSTRACT FROM AUTHOR]

Abstract: To study the microscopic reasons for the embrittlement of the bulk metallic glasses, the local structures around main constituent atoms, i.e. Zr, Ni and Cu in the Zr60Al15Ni25, Ni60Nb20Ti15Zr5 and Cu60Zr30Ti10 glasses (numbers indicate at.%) were investigated by X-ray absorption fine structure measurements. The fluctuations in the interatomic distance (σ 2) of the main constituent atoms in the three metallic glasses are deduced from the results. The σ 2 value for Zr in the Zr60Al15Ni25 was highest in terms of temperature variation as well as in the absolute value among the three metallic glasses even though Zr has the largest atomic size among the constituent atoms. A peak in the Fourier transform of the Zr K-edge for Zr60Al15Ni25 at a short distance may be associated with oxygen around Zr atoms. [Copyright &y& Elsevier]

Nd-Fe-B sintered magnets are used for motors of hybrid or electric vehicles due to their high energy products. Dy is added to Nd-Fe-B sintered magnets to work in a high temperature environment. Although the addition of Dy decreases the magnetization of Nd-Fe-B magnets, it increases coercivity; a decrease in the amount of Dy is strongly required. Recently, Nd-Fe-B sintered magnets with a grain size of 1 μm achieved high coercivity of ∼20 kOe without the addition of Dy or other heavy rare earth elements. In this paper, the microstructure of their magnets was observed and compared to magnets with a grain size of ∼3 μm. The coercivity of magnets consisting of larger particles was 17 kOe. Microstructures were observed by the scanning electron microscope and the shapes of grains and the distribution of the Nd-rich phase were evaluated. The observation was promoted in two directions. One direction is the plane perpendicular to the magnetically aligned direction (c plane side) and the other is the side parallel to the magnetically aligned direction (c axis side). For magnets consisting of smaller particles, the shapes of grains are isotropic for the c plane side and elongated for the c axis side. The angle of minor axis prefers to be parallel to magnetically aligned direction. The distribution of the Nd-rich phase for magnets was also evaluated for both magnets. The distribution of the Nd-rich phase at triple junctions for the magnets with smaller particles becomes homogeneous compared to that for magnets with larger particles. It is considered that Dy-free magnets with high coercivity were realized by the achievement of homogeneous distribution of Nd-rich phase besides decreasing grain size. [ABSTRACT FROM AUTHOR]

We present a study of the dust associated with the core-collapse supernova SN 1995N. Infrared emission detected 14–15 yr after the explosion was previously attributed to thermally echoing circumstellar material (CSM) associated with the supernova (SN) progenitor. We argue that this late-time emission is unlikely to be an echo, and is more plausibly explained by newly formed dust in the SN ejecta, indirectly heated by the interaction between the ejecta and the CSM. Further evidence in support of this scenario comes from emission-line profiles in spectra obtained 22 yr after the explosion; these are asymmetric, showing greater attenuation on the red wing, consistent with absorption by dust within the expanding ejecta. The spectral energy distribution and emission-line profiles at epochs later than ∼5000 d are both consistent with the presence of about 0.4 M⊙ of amorphous carbon dust. The onset of dust formation is apparent in archival optical spectra, taken between 700 and 1700 d after the assumed explosion date. As this is considerably later than most other instances where the onset of dust formation has been detected, we argue that the explosion date must be later than previously assumed. [ABSTRACT FROM AUTHOR]

Dust destruction by supernovae is one of the main processes removing dust from the interstellar medium (ISM). Estimates of the efficiency of this process, both theoretical and observational, typically assume a shock propagating into a homogeneous medium, whereas the ISM possesses significant substructure in reality. We self-consistently model the dust and gas properties of the shocked ISM in three supernova remnants (SNRs), using X-ray and infrared (IR) data combined with corresponding emission models. Collisional heating by gas with properties derived from X-ray observations produces dust temperatures too high to fit the far-IR fluxes from each SNR. An additional colder dust component is required, which has a minimum mass several orders of magnitude larger than that of the warm dust heated by the X-ray emitting gas. Dust-to-gas mass ratios indicate that the majority of the dust in the X-ray emitting material has been destroyed, while the fraction of surviving dust in the cold component is plausibly close to unity. As the cold component makes up virtually all the total dust mass, destruction time-scales based on homogeneous models, which cannot account for multiple phases of shocked gas and dust, may be significantly overestimating actual dust destruction efficiencies, and subsequently underestimating grain lifetimes. [ABSTRACT FROM AUTHOR]

We search for far-infrared (FIR) counterparts of known supernova remnants (SNRs) in the Galactic plane (360° in longitude and |$b = \pm \, 1^{\circ }$|⁠) at 70–500  μ m with Herschel. We detect dust signatures in 39 SNRs out of 190, made up of 13 core-collapse supernovae (CCSNe), including 4 Pulsar Wind Nebulae (PWNe), and 2 Type Ia SNe. A further 24 FIR detected SNRs have unknown types. We confirm the FIR detection of ejecta dust within G350.1−0.3, adding to the known sample of ∼ 10 SNRs containing ejecta dust. We discover dust features at the location of a radio core at the centre of G351.2+0.1, indicating FIR emission coincident with a possible Crab-like compact object, with dust temperature and mass of Td  = 45.8 K and Md  = 0.18 M⊙, similar to the PWN G54.1+0.3. We show that the detection rate is higher among young SNRs. We produce dust temperature maps of 11 SNRs and mass maps of those with distance estimates, finding dust at temperatures |$15\, \lesssim \, T_d\, \lesssim \, 40$|  K. If the dust is heated by shock interactions the shocked gas must be relatively cool and/or have a low density to explain the observed low grain temperatures. [ABSTRACT FROM AUTHOR]

Inelastic neutron scattering measurements of magnetic excitations in hole-doped high-Tc cuprates La2-xSrxCuO4 (x = 0 and 0.075) have been performed over a wide temperature range of 5-500 K extending beyond the pseudogap temperature of ~ 360 K for x = 0.075. For x = 0, the two-dimensional spin-wave excitations at low temperatures are thermally robust and the dispersion is slightly softened on heating up to T = 400 K. For x = 0.075, the spin-wave-like excitations in the upper part of the hourglass-shaped dispersion remain at T = 300 K. However, further heating above T = 400 K induces a broad ridge centered at (1/2, 1/2); thereby the hourglass-shaped dispersion becomes blurred above the pseudogap temperature. The localized spin nature of magnetic excitations below T * suggests that the pseudogap is related to the proximity to a Mott insulator rather than being a precursor of Cooper pairs. [ABSTRACT FROM AUTHOR]

We search for far-infrared counterparts of known supernova remnants (SNRs) in the Galactic plane (10° < | l | < 60°) at 70–500 μm using the Herschel Infrared Galactic Plane Survey (Hi-GAL). Of 71 sources studied, we find that 29 (41   per cent) SNRs have a clear FIR detection of dust emission associated with the SNR. Dust from 8 of these is in the central region, and 4 indicate pulsar wind nebulae (PWNe) heated ejecta dust. A further 23 have dust emission in the outer shell structures which is potentially related to swept-up material. Many Galactic SNe have dust signatures but we are biased towards detecting ejecta dust in young remnants and those with a heating source (shock or PWN). We estimate the dust temperature and mass contained within three PWNe, G11.2–0.3, G21.5–0.9, and G29.7–0.3, using modified blackbody fits. To more rigorously analyse the dust properties at various temperatures and dust emissivity index β, we use point process mapping (PPMAP). We find significant quantities of cool dust (at 20–40 K) with dust masses of M d  =  0.34 ± 0.14 M⊙, M d  =  0.29 ± 0.08 M⊙, and M d  =  0.51 ± 0.13 M⊙ for G11.2–0.3, G21.5–0.9, and G29.7–0.3, respectively. We derive the dust emissivity index for the PWN ejecta dust in G21.5–0.3 to be |$\beta \, =\, 1.4 \pm 0.5$| compared to dust in the surrounding medium where |$\beta \, =\, 1.8 \pm 0.1$|⁠. [ABSTRACT FROM AUTHOR]

We have investigated polarization rotation associated with phonon dynamics in the relaxor ferroelectrics Pb[(Mg1/3Nb2/3)1-xTix]O3. The intensity distributions of the diffuse scattering patterns show intensity- crossover behavior in the monoclinic-C(MC) phase over a wide Ti composition range (29 < x < 32 mol%). The transverse acoustic (TA) mode of the crossover region along the [001] direction softens and is damped, strongly correlating with the central peak intensity, which originates in the polar regions. These results indicate that the lattice can easily deform in the MC phase, and the polarization can rotate easily by associating with the TA mode. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Review article: medical, surgical and radiological management of perianal Crohn's fistulas," by P. J. Tozer and colleagues.

A letter to the editor is presented in response to a review article by S. Thanaraj, P. J. Hamlin, and A. C. Ford regarding granulocyte/monocyte adsorptive apheresis (GMAA) for ulcerative colitis (UC).

We present new Herschel photometric and spectroscopic observations of Supernova 1987A, carried out in 2012. Our dedicated photometric measurements provide new 70 μm data and improved imaging quality at 100 and 160 μm compared to previous observations in 2010. Our Herschel spectra show only weak CO line emission, and provide an upper limit for the 63 μm [O I] line flux, eliminating the possibility that line contaminations distort the previously estimated dust mass. The far-infrared spectral energy distribution (SED) is well fitted by thermal emission from cold dust. The newly measured 70 μm flux constrains the dust temperature, limiting it to nearly a single temperature. The far-infrared emission can be fitted by 0.5 ± 0.1 M☼ of amorphous carbon, about a factor of two larger than the current nucleosynthetic mass prediction for carbon. The observation of SiO molecules at early and late phases suggests that silicates may also have formed and we could fit the SED with a combination of 0.3 M☼ of amorphous carbon and 0.5 M☼ of silicates, totalling 0.8 M☼ of dust. Our analysis thus supports the presence of a large dust reservoir in the ejecta of SN 1987A. The inferred dust mass suggests that supernovae can be an important source of dust in the interstellar medium, from local to high-redshift galaxies. [ABSTRACT FROM AUTHOR]

The authors investigated the voltage control of a magnetic anisotropy field for perpendicular-magnetic tunnel junctions (p-MTJs) with low and high resistance-area (RA) products and for synthetic antiferromagnetic free and pinned layers. It was found that the sample with low RA products was more sensitive to the applied bias voltage than the sample with high RA products. The bias voltage effect was less pronounced for our sample with the synthetic antiferromagnetic layer for high RA products compared to the MTJs with single free and pinned layers. [ABSTRACT FROM AUTHOR]

Introduction: Several previous studies have reported that individual PLMS activities are associated with autonomic nervous system activity occurring shortly before each PLMS activities. However, there is no study investigating dynamic changes of autonomic nervous system activity before onset of PLMS. The aim of this study is to detect changes in heart rate variability (HRV) at the onset of the period in which periodic leg movements during sleep (PLMS) are observed using complex demodulation method. Materials and methods: This study enrolled 14 patients diagnosed as having idiopathic PLMS disorder (PLMD). HRV-variables and spectral power of fluctuation of mean frequency in a high frequency band (HF-fluctuation; HFF) during sleep stage 2 were analyzed and compared between the period with and without PLMS. In addition, the changes of above parameters in periods in transition from the period without PLMS to that with PLMS were explored. Results: Spectral power in the low frequency (LF) band and very low frequency (VLF) band were higher in the period with PLMS. Additionally, the average frequency in HFF was higher and the frequency in this band fluctuated during the period with PLMS with remarkable elevation of HFF. Moreover, the spectral powers in HFF, LF, and VLF were remarkably elevated shortly before the beginning of the period with PLMS (HFF, −65s; LF, −53s; and VLF, −45s). Conclusion: The elevation of sympathetic nervous activity and the HF frequency fluctuation can occur several tens of seconds before the beginning of the period with PLMS. Dynamic changes in the autonomic nervous system activity could be related with the vulnerability to PLMS occurrence during a night. Acknowledgements: This study was supported by an Intramural Research Grant (21B-4) for Neurological and Psychiatric Disorders of NCNP, Fellowship for Young Clinical Sleep Researchers of the Japan Sleep Research Society, and MEXT/JSPS KAKENHI (Grant-in-Aid for Young Scientists, Grant Number: 24791235). [Copyright &y& Elsevier]