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We report magnetic properties of a $3{d}^{9}$ $({\mathrm{Cu}}^{2+})$ magnetic insulator ${\mathrm{Cu}}_{2}{\mathrm{OSO}}_{4}$ measured on both powder and single crystal. The magnetic atoms of this compound form layers whose geometry can be described either as a system of chains coupled through dimers or as a kagome lattice where every third spin is replaced by a dimer. Specific heat and DC susceptibility show a magnetic transition at 20 K, which is also confirmed by neutron scattering. Magnetic entropy extracted from the specific heat data is consistent with an $S=1/2$ degree of freedom per ${\mathrm{Cu}}^{2+}$, and so is the effective moment extracted from DC susceptibility. The ground state has been identified by means of neutron diffraction on both powder and single crystal and corresponds to an $\ensuremath{\sim}{120}^{\ensuremath{\circ}}$ spin structure in which ferromagnetic intradimer alignment results in a net ferrimagnetic moment. No evidence is found for a change in lattice symmetry down to 2 K. Our results suggest that ${\mathrm{Cu}}_{2}{\mathrm{OSO}}_{4}$ represents a type of model lattice with frustrated interactions where interplay between magnetic order, thermal and quantum fluctuations can be explored.

The dimerized quantum magnet ${\mathrm{BaCuSi}}_{2}{\mathrm{O}}_{6}$ was proposed as an example of ``dimensional reduction'' arising near the magnetic-field-induced quantum critical point (QCP) due to perfect geometrical frustration of its interbilayer interactions. We demonstrate by high-resolution neutron spectroscopy experiments that the effective intrabilayer interactions are ferromagnetic, thereby excluding frustration. We explain the apparent dimensional reduction by establishing the presence of three magnetically inequivalent bilayers, with ratios $3\ensuremath{\mathbin:}2\ensuremath{\mathbin:}1$, whose differing interaction parameters create an extra field-temperature scaling regime near the QCP with a nontrivial but nonuniversal exponent. We demonstrate by detailed quantum Monte Carlo simulations that the magnetic interaction parameters we deduce can account for all the measured properties of ${\mathrm{BaCuSi}}_{2}{\mathrm{O}}_{6}$, opening the way to a quantitative understanding of nonuniversal scaling in any modulated layered system.

We study the dynamics and interactions of the critical fluctuations of the Verwey transition in magnetite (${\mathrm{Fe}}_{3}{\mathrm{O}}_{4}$) in the pretransition region by means of inelastic neutron scattering experiments on a natural single crystal. We find that a ${\mathrm{\ensuremath{\Delta}}}_{5}$ mode interacts strongly with a central peak of order parameter fluctuations, whose width is determined by the order parameter coherence time. This is compared with pump-probe experiments, which we formerly explained in terms of fluctuation-assisted stimulated Raman scattering. Our estimates of the order parameter correlation time from experiments in the energy domain (inelastic neutron scattering experiments) and in the time domain (pump-probe experiments) coincide, thus giving further credit to our previous interpretation of pump-probe experiments and confirming that the Verwey transition is of the order-disorder type, without phonon softening.

The antiferromagnetic compound $\mathrm{Ba}(\mathrm{TiO}){\mathrm{Cu}}_{4}{({\mathrm{PO}}_{4})}_{4}$ contains square cupola of corner-sharing ${\mathrm{CuO}}_{4}$ plaquettes, which were proposed to form effective quadrupolar order. To identify the magnetic structure, we have performed spherical neutron polarimetry measurements. Based on symmetry analysis and careful measurements, we conclude that the orientation of the ${\mathrm{Cu}}^{2+}$ spins form a noncollinear in-out structure with spins approximately perpendicular to the ${\mathrm{CuO}}_{4}$ motif. Strong Dzyaloshinskii-Moriya interaction naturally lends itself to explain this phenomenon. The identification of the ground-state magnetic structure should serve well for future theoretical and experimental studies into this and closely related compounds.

(Abridged) The WMAP 5-year data strongly limit deviations from the minimal LCDM model. We constrain the physics of inflation via Gaussianity, adiabaticity, the power spectrum shape, gravitational waves, and spatial curvature. We also constrain the properties of dark energy, parity-violation, and neutrinos. We detect no convincing deviations from the minimal model. The parameters of the LCDM model, derived from WMAP combined with the distance measurements from the Type Ia supernovae (SN) and the Baryon Acoustic Oscillations (BAO), are: Omega_b=0.0456+-0.0015, Omega_c=0.228+-0.013, Omega_Lambda=0.726+-0.015, H_0=70.5+-1.3 km/s/Mpc, n_s=0.960+-0.013, tau=0.084+-0.016, and sigma_8=0.812+-0.026. With WMAP+BAO+SN, we find the tensor-to-scalar ratio r1 is disfavored regardless of r. We obtain tight, simultaneous limits on the (constant) equation of state of dark energy and curvature. We provide a set of "WMAP distance priors," to test a variety of dark energy models. We test a time-dependent w with a present value constrained as -0.33, Comment: 52 pages, 21 figures, accepted for publication in ApJS. (v2) References added. Cosmological parameters updated with the latest union supernova compilation (Kowalski et al. arXiv:0804.4142)

We present the results of elastic and inelastic neutron scattering measurements on nonsuperconducting $\mathrm{Ba}(\mathrm{Fe}{}_{0.957}\mathrm{Cu}{}_{0.043}){}_{2}\mathrm{As}{}_{2}$, a composition close to a quantum critical point between antiferromagnetic (AFM) ordered and paramagnetic phases. By comparing these results with the spin fluctuations in the low-Cu composition as well as the parent compound ${\mathrm{BaFe}}_{2}{\mathrm{As}}_{2}$ and superconducting $\mathrm{Ba}{({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Ni}}_{x})}_{2}{\mathrm{As}}_{2}$ compounds, we demonstrate that paramagnon-like spin fluctuations are evident in the antiferromagnetically ordered state of $\mathrm{Ba}{({\mathrm{Fe}}_{0.957}{\mathrm{Cu}}_{0.043})}_{2}{\mathrm{As}}_{2}$, which is distinct from the AFM-like spin fluctuations in the superconducting compounds. Our observations suggest that Cu substitution decouples the interaction between quasiparticles and the spin fluctuations. We also show that the spin-spin correlation length $\ensuremath{\xi}(T)$ increases rapidly as the temperature is lowered and find $\ensuremath{\omega}/T$ scaling behavior, the hallmark of quantum criticality, at an antiferromagnetic quantum critical point.

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its covariance matrix. These can be used as inputs for cosmological analyses. The polarized sky signal is parameterized as the sum of three components: CMB, synchrotron emission, and thermal dust emission. The polarized Galactic components are modeled with spatially varying power law spectral indices for the synchrotron, and a fixed power law for the dust, and their component maps are estimated as by-products. We apply the method to simulated low resolution maps with pixels of side 7.2 degrees, using diagonal and full noise realizations drawn from the WMAP noise matrices. The CMB maps are recovered with goodness of fit consistent with errors. Computing the likelihood of the E-mode power in the maps as a function of optical depth to reionization, tau, for fixed temperature anisotropy power, we recover tau=0.091+-0.019 for a simulation with input tau=0.1, and mean tau=0.098 averaged over 10 simulations. A `null' simulation with no polarized CMB signal has maximum likelihood consistent with tau=0. The method is applied to the five-year WMAP data, using the K, Ka, Q and V channels. We find tau=0.090+-0.019, compared to tau=0.086+-0.016 from the template-cleaned maps used in the primary WMAP analysis. The synchrotron spectral index, beta, averaged over high signal-to-noise pixels with standard deviation sigma(beta)

Summary A mathematical model based on finite differences was presented, which improved the accuracy of current modelling techniques during the cooling period for conduction heating foods undergoing thermal processing. The surface heat transfer coefficient between can and cooling fluid was incorporated into the finite difference equations, with a value of 600 W m−2 K−1 chosen from literature and confirmed by calculations from surface temperature measurements and a correlation of the form Nu = f(GrxPr)n. Experimental results were obtained for a cylinder of Sylgard 184 elastomer (length 62mm, diameter 57mm) and a polypropylene block (26x91x141 mm). At the end of cooling the heat transfer coefficient model predicted a centre temperature just 2.5°C above the measured value for polypropylene, and for Sylgard 184 this difference was 2.7°C. This model will improve both real-time process control via the ‘derived-value’ technique, and the use of controlled pressure cooling with less damage to containers. Optimization of quality factors will also be improved with increased knowledge of in-container temperatures.

A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) fits not only the three year WMAP temperature and polarization data, but also small scale CMB data, light element abundances, large-scale structure observations, and the supernova luminosity/distance relationship. Using WMAP data only, the best fit values for cosmological parameters for the power-law flat LCDM model are (Omega_m h^2, Omega_b h^2, h, n_s, tau, sigma_8) = 0.1277+0.0080-0.0079, 0.02229+-0.00073, 0.732+0.031-0.032, 0.958+-0.016, 0.089+-0.030, 0.761+0.049-0.048). The three year data dramatically shrink the allowed volume in this six dimensional parameter space. Assuming that the primordial fluctuations are adiabatic with a power law spectrum, the WMAP data_alone_ require dark matter, and favor a spectral index that is significantly less than the Harrison-Zel'dovich-Peebles scale-invariant spectrum (n_s=1, r=0). Models that suppress large-scale power through a running spectral index or a large-scale cut-off in the power spectrum are a better fit to the WMAP and small scale CMB data than the power-law LCDM model; however, the improvement in the fit to the WMAP data is only Delta chi^2 = 3 for 1 extra degree of freedom. The combination of WMAP and other astronomical data yields significant constraints on the geometry of the universe, the equation of state of the dark energy, the gravitational wave energy density, and neutrino properties. Consistent with the predictions of simple inflationary theories, we detect no significant deviations from Gaussianity in the CMB maps.

This paper describes numerical simulations of the non-isothermal, laminar flow of Newtonian and non-Newtonian liquids inside rotating cylindrical cans containing a headspace air bubble. Two modes of rotation are considered: axial rotation about a horizontal axis and end-over-end rotation. The rotational speed is held constant so that once initial transients have decayed the flow field in both cases is periodic. The aim of the numerical simulations, carried out using the ANSYS CFX computational fluid dynamics software, is to compare liquid heating times for different flow conditions. To reduce computational run times the calculations are carried out for a liquid with an artificially high value of thermal diffusivity. For axial rotation the simulations have been carried out using 2D and 3D models and it is shown that a 2D model can identify trends in heating times. In both end-over-end and axial modes, rotational speeds and radii of rotation are identified which minimize the heating time. The conditions are shown to correspond closely to those which maximize a measure of mixing in previous studies of isothermal flow.

Open anterior fracture dislocation of the hip is an extremely rare injury and is the result of a violent trauma. Such a case is being reported in a 15-year-old female, who also had other adjacent bony injuries. In spite of early treatment, necrosis and infection could not be controlled, resulting in permanent disability in this young girl.

Results are reported from the first flight of a new balloon-borne instrument, BAM (Balloon-borne Anisotropy Measurement), designed to search for cosmic microwave background (CMB) anisotropy. The instrument uses a cryogenic differential Fourier transform spectrometer to obtain data in five spectral channels whose central frequencies lie in the range 3.7-8.5 cm-1. The spectrometer is coupled to an off-axis prime focus telescope; the combination yields difference spectra of two regions on the sky defined by 07 FWHM beams separated by 36. Single differences obtained at 10 sky positions show statistically significant fluctuations. Assuming Gaussian correlated anisotropy, for the band average 3.1-9.2 cm-1, one finds ΔT/T = 3.1−1.1+3.1 × 10-5 (90% confidence interval) for a correlation angle of 12. This corresponds to Qflat = 35.9−6.3+17.7 μK (1 σ).

The relationship between antiferromagnetic spin fluctuations and superconductivity has become a central topic of research in studies of superconductivity in the iron pnictides. We present unambiguous evidence of the absence of magnetic fluctuations in the nonsuperconducting collapsed tetragonal phase of CaFe2As2 via inelastic neutron scattering time-of-flight data, which is consistent with the view that spin fluctuations are a necessary ingredient for unconventional superconductivity in the iron pnictides. We demonstrate that the collapsed tetragonal phase of CaFe2As2 is nonmagnetic, and discuss this result in light of recent reports of high-temperature superconductivity in the collapsed tetragonal phase of closely related compounds.

BaMn${}_{2}$As${}_{2}$ is a local-moment antiferromagnetic insulator with a N\'eel temperature ${T}_{\mathrm{N}}$ of 625 K and a large ordered moment of 3.9 ${\ensuremath{\mu}}_{\mathrm{B}}$/Mn. Remarkably, this compound can be driven metallic by the substitution of as little as 1.6$%$ K for Ba while retaining essentially the same ordered magnetic moment and N\'eel temperature, as previously reported. Here, using both powder and single crystal neutron diffraction we show that the local moment antiferromagnetic order in Ba${}_{1\ensuremath{-}x}$K${}_{x}$Mn${}_{2}$As${}_{2}$ remains robust up to $x=0.4$. The ordered moment is nearly independent of $x$ for 0 $\ensuremath{\le}x\ensuremath{\le}$ 0.4 and ${T}_{\mathrm{N}}$ decreases to 480 K at $x=0.4$.

The phonon dispersion was measured at room temperature along (0,0,L) in the tetragonal phase of LaFeAsO using inelastic x-ray scattering. Spin-polarized first-principles calculations imposing various types of antiferromagnetic order are in better agreement with the experimental results than nonmagnetic calculations, although the measurements were made well above the magnetic ordering temperature, T_N. Splitting observed between two A_{1g} phonon modes at 22 and 26 meV is only observed in spin-polarized calculations. Magneto-structural effects similar to those observed in the AFe_2As_2 materials are confirmed present in LaFeAsO. The presence of Fe-spin is necessary to find reasonable agreement of the calculations with the measured spectrum well above T_N. On-site Fe and As force constants show significant softening compared to nonmagnetic calculations, however an investigation of the real-space force constants associates the magnetoelastic coupling with a complex renormalization instead of softening of a specific pairwise force., Comment: 7 pages, 4 figures

Inelastic neutron scattering measurements on Ba(Fe$_{0.963}$Ni$_{0.037}$)$_2$As$_2$ manifest a neutron spin resonance in the superconducting state with anisotropic dispersion within the Fe layer. Whereas the resonance is sharply peaked at Q$_{AFM}$ along the orthorhombic a axis, the resonance disperses upwards away from Q$_{AFM}$ along the b axis. In contrast to the downward dispersing resonance and hour-glass shape of the spin excitations in superconducting cuprates, the resonance in electron-doped BaFe$_2$As$_2$ compounds possesses a magnon-like upwards dispersion., Comment: 5 pages and 3 figures + supplement(3pages and 1 figure)

The spin fluctuation spectra from nonsuperconducting Cu-substituted, and superconducting Co-substituted, BaFe(2)As(2) are compared quantitatively by inelastic neutron scattering measurements and are found to be indistinguishable. Whereas diffraction studies show the appearance of incommensurate spin-density wave order in Co and Ni substituted samples, the magnetic phase diagram for Cu substitution does not display incommensurate order, demonstrating that simple electron counting based on rigid-band concepts is invalid. These results, supported by theoretical calculations, suggest that substitutional impurity effects in the Fe plane play a significant role in controlling magnetism and the appearance of superconductivity, with Cu distinguished by enhanced impurity scattering and split-band behavior.

Inelastic neutron scattering measurements on $\mathrm{Ba}{({\mathrm{Fe}}_{0.925}{\mathrm{Mn}}_{0.075})}_{2}{\mathrm{As}}_{2}$ manifest spin fluctuations at two different wave vectors, ${\mathbf{Q}}_{\mathrm{stripe}}=(\frac{1}{2},\frac{1}{2},1)$ and ${\mathbf{Q}}_{\text{N\'eel}}=(1,0,1)$, corresponding to the expected stripe spin-density wave order and checkerboard antiferromagnetic order in the tetragonal $I4/mmm$ cell, respectively. Below ${T}_{N}=80$ K, long-range stripe magnetic ordering occurs and sharp spin wave excitations appear at ${\mathbf{Q}}_{\mathrm{stripe}}$ while broad and diffusive spin fluctuations remain at ${\mathbf{Q}}_{\text{N\'eel}}$ at all temperatures. Low concentrations of Mn dopants nucleate local moment spin fluctuations at ${\mathbf{Q}}_{\text{N\'eel}}$ that compete with itinerant spin fluctuations at ${\mathbf{Q}}_{\mathrm{stripe}}$ and may disrupt the development of superconductivity.

The magnetic excitations in the paramagnetic-tetragonal phase of underdoped Ba(Fe${}_{0.953}$Co${}_{0.047}$)${}_{2}$As${}_{2}$, as measured by inelastic neutron scattering, can be well described by a phenomenological model with purely diffusive spin dynamics. At low energies, the spectrum around the magnetic ordering vector ${\mathbf{Q}}_{\mathrm{AFM}}$ consists of a single peak with elliptical shape in momentum space. At high energies, this inelastic peak is split into two peaks across the direction perpendicular to ${\mathbf{Q}}_{\mathrm{AFM}}$. We use our fittings to argue that such a splitting is not due to incommensurability or propagating spin-wave excitations, but is rather a consequence of the anisotropies in the Landau damping and in the magnetic correlation length, both of which are allowed by the tetragonal symmetry of the system. We also measure the magnetic spectrum deep inside the magnetically ordered phase, and find that it is remarkably similar to the spectrum of the paramagnetic phase, revealing the strongly overdamped character of the magnetic excitations.

The spin fluctuation spectra from nonsuperconducting Cu-substituted, and superconducting Co-substituted, BaFe(2)As(2) are compared quantitatively by inelastic neutron scattering measurements and are found to be indistinguishable. Whereas diffraction studies show the appearance of incommensurate spin-density wave order in Co and Ni substituted samples, the magnetic phase diagram for Cu substitution does not display incommensurate order, demonstrating that simple electron counting based on rigid-band concepts is invalid. These results, supported by theoretical calculations, suggest that substitutional impurity effects in the Fe plane play a significant role in controlling magnetism and the appearance of superconductivity, with Cu distinguished by enhanced impurity scattering and split-band behavior.

Neutron diffraction studies of $\mathrm{Ba}({\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x}{)}_{2}{\mathrm{As}}_{2}$ reveal that commensurate antiferromagnetic order gives way to incommensurate magnetic order for Co compositions between $0.056lxl0.06$. The incommensurability has the form of a small transverse splitting (0, $\ifmmode\pm\else\textpm\fi{}ϵ$, 0) from the commensurate antiferromagnetic propagation vector ${\mathbf{Q}}_{\mathrm{AFM}}=(1,0,1)$ (in orthorhombic notation) where $\mathbit{ϵ}\ensuremath{\approx}0.02\ensuremath{-}0.03$ and is composition dependent. The results are consistent with the formation of a spin-density wave driven by Fermi surface nesting of electron and hole pockets and confirm the itinerant nature of magnetism in the iron arsenide superconductors.

Neutron diffraction studies of Ba(Fe(1-x)Co(x))(2)As)(2) reveal that commensurate antiferromagnetic order gives way to incommensurate magnetic order for Co compositions between 0.056x0.06. The incommensurability has the form of a small transverse splitting (0, ± ε, 0) from the commensurate antiferromagnetic propagation vector Q(AFM) = (1,0,1) (in orthorhombic notation) where ε ≈ 0.02-0.03 and is composition dependent. The results are consistent with the formation of a spin-density wave driven by Fermi surface nesting of electron and hole pockets and confirm the itinerant nature of magnetism in the iron arsenide superconductors.

We present the list of point sources found in the WMAP 5-year maps. The technique used in the first-year and three-year analysis now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the galactic plane to a 2 Jy limit, with SNR > 4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the CMB anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.

This paper focuses on cosmological constraints derived from analysis of WMAP data alone. A simple LCDM cosmological model fits the five-year WMAP temperature and polarization data. The basic parameters of the model are consistent with the three-year data and now better constrained: Omega_b h^2 = 0.02273+-0.00062, Omega_c h^2 = 0.1099+-0.0062, Omega_L = 0.742+-0.030, n_s = 0.963+0.014- 0.015, tau = 0.087+-0.017, sigma_8 = 0.796+-0.036. With five years of polarization data, we have measured the optical depth to reionization, tau>0, at 5 sigma significance. The redshift of an instantaneous reionization is constrained to be z_reion = 11.0+-1.4 with 68% confidence. This excludes a sudden reionization of the universe at z=6 at more than 3.5 sigma significance, suggesting that reionization was an extended process. Using two methods for polarized foreground cleaning we get consistent estimates for the optical depth, indicating an error due to foreground treatment of tau~0.01. This cosmological model also fits small-scale CMB data, and a range of astronomical data measuring the expansion rate and clustering of matter in the universe. We find evidence for the first time in the CMB power spectrum for a non-zero cosmic neutrino background, or a background of relativistic species, with the standard three light neutrino species preferred over the best-fit LCDM model with N_eff=0 at >99.5% confidence, and N_eff > 2.3 (95% CL) when varied. The five-year WMAP data improve the upper limit on the tensor-to-scalar ratio to r < 0.43 (95% CL), for power-law models. With longer integration we find no evidence for a running spectral index, with dn_s/dlnk = -0.037+-0.028., 49 pages, 18 figures, version accepted by ApJS. Original Section 2 moved to separate paper. For higher quality figs, see version on http://lambda.gsfc.nasa.gov

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530, and individual l-modes have S/N>1 for l, 29 pages, 13 figures, accepted by ApJS

The phonon dispersion was measured at room temperature (above the Neel temperature TN) along (0,0,L) in the tetragonal phase of LaFeAsO using inelastic x-ray scattering. Magnetostructural effects are well documented in the AFe2As2-based (A = Ca, Sr, Ba, Eu) systems. Only recently have single crystals of LaFeAsO become available. The experimentally observed splitting between two A1g phonon modes at 22 and 26 meV is only reproduced in spin-polarized calculations. Magnetostructural effects similar to those observed in the AFe2As2 materials are confirmed to be present in LaFeAsO. This is discussed in terms of the strong antiferromagnetic correlations that are known to persist above TN and into the tetragonal phase.

The postnatal development of the photoreceptor of the cat was studied using physiological and anatomical methods. The late receptor potential (LRP) was recorded in vitro and the threshold and maximum amplitude determined. The same specimens used in the electrophysiological studies were then prepared for microscopy, and rod cell outer and inner segment length and diameter, photoreceptor density, and inter-receptor distance were determined. A small LRP was first recorded at 9--10 days, but only at very high stimulus intensities. Thereafter, there was a rapid decrease in the threshold and an increase in the amplitude of the LRP. The threshold reached adult values at 17--18 days, while the amplitude of the LRP was adultlike at 23--26 days. Of the anatomical parameters examined, inter-receptor spacing and rod cell diameters seem to be most clearly associated, respectively, with the attainment of adult LRP threshold and amplitude. Outer segment length was adult-like at 35--43 days of age and thus postdated physiological maturity of the photoreceptor. These observations suggest that the surface area of the rod cell outer segment tips is more critical in the development of the adult LRP than is the number of discs in the outer segment. In addition, changes over time in the mean diameter and length of rod cell inner segments follows the pattern of ontogenetic changes in LRP amplitude. These findings imply a close relationship during ontogeny between the metabolic functions of the inner segment and phototransduction at the outer segment disc.

The postnatal development of the rod photoreceptor of normally-reared and dark-reared pigmented rabbits was studied using physiological and anatomical methods. The late receptor potential (LRP) was recorded in vitro and the threshold and maximum amplitude determined. The same specimens used in the electrophysiological studies were then prepared for microscopy, and rod cell outer and inner segment dimensions and photoreceptor spacing were determined. In the light-reared animals a small LRP was first recorded at 5 days, but only at very high stimulus intensities. Thereafter, there was a rapid decrease in the threshold and an increase in the amplitude of the LRP. The threshold and amplitude of the LRP reached adult values at 14 days. Of the anatomical parameters, maturation of inter-receptor spacing (14 days) is clearly associated with the attainment of the adult LRP amplitude levels. Outer segment length was also adultlike by 14 days of age and thus paralleled physiological maturity of the photoreceptor. Changes over time in the mean diameter and length of rod cell inner segments (adultlike at 21 days) follows the pattern of ontogenetic maturation of the LRP. These findings imply a close relationship during ontogeny between the LRP and development of the outer segment. In dark-reared pups there is a delay in the maturation of the photoreceptor mosaic, but by 4 weeks of age, physiological characteristics of the photoreceptor are adultlike.

Twenty-six cases of fractures of the proximal end of the femur were studied to assess the role of osteomalacia. Biochemical, radiological and histological investigations were carried out in all the cases. Osteomalacia, commonly subclinical, was found to be the underlying cause in 65 per cent of cases. Histological analysis of iliac crest biopsy was the only reliable way of diagnosing subclinical osteomalacia.

Most common tumours of ilium are chondrosarcoma and reticulum cell sarcoma. Giant cell tumour commonly presents at the ends of long bones. It is quite uncommon to find osteoclastoma in flat bones, especially ilium. This is the only case of osteoclastoma of ilium seen during the last 7 years in this institution and is reported for its rarity.

Refractile inclusion bodies (approximately 0.80 micron in size) were found in the inner segments of cone photoreceptors in the aging human retina. They were easily resolved with the light microscope. They were never seen in rods, and occurred primarily in retinas from eye donors older than 40 years of age. The incidence of these inclusion bodies is related significantly to age (they occur more frequently with increasing age) and to sex (they are more likely to occur in the aging female than in the aging male). They were often smaller in size and fewer in number in the cones of males compared with females, and in males, fewer cones contained the RB than in females. Electron microscopy revealed that these inclusions are membrane-bound organelles having granular, fibrous, and tubular subcomponents. The occurrence of the RB appears to be unrelated to specific disease processes, medications in use at the time of enucleation, or specimen preparation times.

We have used inelastic neutron scattering to measure the magnetic excitation spectrum along the high-symmetry directions of the first Brillouin zone of the magnetic skyrmion hosting compound Cu$_2$OSeO$_3$. The majority of our scattering data are consistent with the expectations of a recently proposed model for the magnetic excitations in Cu$_2$OSeO$_3$, and we report best-fit parameters for the dominant exchange interactions. Important differences exist, however, between our experimental findings and the model expectations. These include the identification of two energy scales that likely arise due to neglected anisotropic interactions. This feature of our work suggests that anisotropy should be considered in future theoretical work aimed at the full microscopic understanding of the emergence of the skyrmion state in this material., Comment: 5 pages, 6 figures

We present inelastic neutron scattering data across the Verwey transition in magnetite, obtained for a single crystal via a detwinning method. We provide direct evidence of the influence of the charge order on the transverse-acoustic phonons, associated with discontinuous hardening and narrowing at the transition temperature, and energy splitting for different polarizations. This contrasts with the behavior of the transverse-optical X3 mode, which does not present any critical anomaly, contrary to theoretical expectations. Our data indicate that the incommensurate fluctuations occurring above the critical temperature become locked to the lattice at the transition point, through a mechanism similar to the crystallization of a two-dimensional liquid on a solid surface. Our results also contribute to clarify the different dynamics and mutual interactions of the electronic and structural modes in the Verwey transition. © 2017 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

In vortex-like spin arrangements, multiple spins can combine into emergent multipole moments. Such multipole moments have broken space-inversion and time-reversal symmetries, and can therefore exhibit linear magnetoelectric (ME) activity. Three types of such multipole moments are known: toroidal, monopole, and quadrupole moments. So far, however, the ME-activity of these multipole moments has only been established experimentally for the toroidal moment. Here, we propose a magnetic square cupola cluster, in which four corner-sharing square-coordinated metal-ligand fragments form a noncoplanar buckled structure, as a promising structural unit that carries an ME-active multipole moment. We substantiate this idea by observing clear magnetodielectric signals associated with an antiferroic ME-active magnetic quadrupole order in the real material Ba(TiO)Cu$_4$(PO$_4$)$_4$. The present result serves as a useful guide for exploring and designing new ME-active materials based on vortex-like spin arrangements., 4 figures