1,043 research outputs found

    Sequential epiretinal membrane removal with internal limiting membrane peeling in brilliant blue G-assisted macular surgery

    Get PDF
    Purpose To assess the selectivity of brilliant blue G (BBG) staining by analysing the morphological components of unstained and stained tissue obtained during epiretinal membrane (ERM) removal with internal limiting membrane (ILM) peeling in BBG-assisted macular surgery. Methods Twenty-six surgical specimens were removed from 13 eyes with epiretinal gliosis during vitrectomy using BBG for ERM and ILM peeling. We included eyes with idiopathic macular pucker, idiopathic macular hole and vitreomacular traction syndrome. The dye was injected into the fluid-filled globe. Unstained and stained epiretinal tissue was harvested consecutively and placed into separate containers. All specimens were processed for conventional transmission electron microscopy. Results The first surgical specimen of all eyes showed no intraoperative staining with BBG and corresponded to masses of cells and collagen. The second surgical specimen demonstrated good staining characteristics and corresponded to the ILM in all patients included. In seven eyes, the ILM specimens were seen with minor cell proliferations such as single cells or a monolayer of cells. Myofibroblasts, fibroblasts and astrocytes were present. In five cases, native vitreous collagen fibrils were found at the ILM. In six of the eyes, ILM specimens were blank. Conclusion Our clinicopathological correlation underlines the selective staining properties of BBG. The residual ILM is selectively stained by BBG even when a small amount of cells and collagen adheres to its vitreal side. To reduce the retinal exposure to the dye, the surgeon might choose to remove the ERM without using the dye, followed by a BBG injection to identify residual ILM

    Strong subadditivity inequality for quantum entropies and four-particle entanglement

    Get PDF
    Strong subadditivity inequality for a three-particle composite system is an important inequality in quantum information theory which can be studied via a four-particle entangled state. We use two three-level atoms in Λ\Lambda configuration interacting with a two-mode cavity and the Raman adiabatic passage technique for the production of the four-particle entangled state. Using this four-particle entanglement, we study for the first time various aspects of the strong subadditivity inequality.Comment: 5 pages, 3 figures, RevTeX4, submitted to PR

    Mother-to-infant and father-to-infant initial emotional involvement

    Get PDF
    While infant attachment has been largely studied, parental attachment is still relatively unknown, especially when referred to fathers. However, it is mainly recognised that parents’ emotional involvement with the newborn contributes to the quality of the interaction and the care they provide. The aim of this study was to study mother-to-infant and father-to-infant initial emotional involvement; namely, differences between mothers and fathers and changes in mother’s emotions toward the neonate within the first days after delivery. The Bonding Scale, an extended Portuguese version of the ‘New Mother-to-Infant Bonding Scale’, was administered during the first two days after childbirth to a sample of 315 mothers and 141 fathers (n = 456), at the Júlio Dinis Maternity Hospital (Portugal). Most mothers and fathers show positive emotions and only a few of them showed negative emotions toward the infant. Maternal and paternal emotional involvement toward the newborn tend to be similar; nevertheless, fathers show less fear and better emotional involvement with the neonate, while mothers are sadder and show more emotions not related to bonding. During the first days following delivery, emotions not related to bonding, such as fear, seem to decrease in mothers.Bial Foundation - Grant 58/02.Human Development and Health Service of the Calouste Gulbenkian Foundation - Grant 48914

    Testing foundations of quantum mechanics with photons

    Full text link
    The foundational ideas of quantum mechanics continue to give rise to counterintuitive theories and physical effects that are in conflict with a classical description of Nature. Experiments with light at the single photon level have historically been at the forefront of tests of fundamental quantum theory and new developments in photonics engineering continue to enable new experiments. Here we review recent photonic experiments to test two foundational themes in quantum mechanics: wave-particle duality, central to recent complementarity and delayed-choice experiments; and Bell nonlocality where recent theoretical and technological advances have allowed all controversial loopholes to be separately addressed in different photonics experiments.Comment: 10 pages, 5 figures, published as a Nature Physics Insight review articl

    Pb0.4Bi1.6Sr2Ca1Cu2O8+xPb_{0.4}Bi_{1.6}Sr_{2}Ca_{1}Cu_{2}O_{8+x} and Oxygen Stoichiometry: Structure, Resistivity, Fermi Surface Topology and Normal State Properties

    Full text link
    Pb0.4Bi1.6Sr2CaCu2O8+xPb_{0.4}Bi_{1.6}Sr_2CaCu_2O_{8+x} (Bi(Pb)Bi(Pb)-2212) single crystal samples were studied using transmission electron microscopy (TEM), abab-plane (ρab\rho_{ab}) and cc-axis (ρc\rho_c) resistivity, and high resolution angle-resolved ultraviolet photoemission spectroscopy (ARUPS). TEM reveals that the modulation in the bb-axis for Pb(0.4)Pb(0.4)-doped Bi(Pb)Bi(Pb)-2212 is dominantly of PbPb-type that is not sensitive to the oxygen content of the system, and the system clearly shows a structure of orthorhombic symmetry. Oxygen annealed samples exhibit a much lower cc-axis resistivity and a resistivity minimum at 8013080-130K. He-annealed samples exhibit a much higher cc-axis resistivity and dρc/dT<0d\rho_c/dT<0 behavior below 300K. The Fermi surface (FS) of oxygen annealed Bi(Pb)Bi(Pb)-2212 mapped out by ARUPS has a pocket in the FS around the Mˉ\bar{M} point and exhibits orthorhombic symmetry. There are flat, parallel sections of the FS, about 60\% of the maximum possible along kx=kyk_x = k_y, and about 30\% along kx=kyk_x = - k_y. The wavevectors connecting the flat sections are about 0.72(π,π)0.72(\pi, \pi) along kx=kyk_x = k_y, and about 0.80(π,π)0.80(\pi, \pi) along kx=kyk_x = - k_y, rather than (π,π)(\pi,\pi). The symmetry of the near-Fermi-energy dispersing states in the normal state changes between oxygen-annealed and He-annealed samples.Comment: APS_REVTEX 3.0, 49 pages, including 11 figures, available upon request. Submitted to Phys. Rev. B

    Radiological anatomy of the ambient cistern in children

    Get PDF
    Ambient cistern (AC) is a thin extension of the subarachnoid space surrounding the brainstem at the level of the mesencephalon and pons. Despite various definitions, it constitutes an important landmark in clinical assessment of intracranial volume reserve. Although it is indisputably useful, there exists no defined standard for radiological examination for the dimensions and ranges in specific age groups. This paper aims to describe the ambient cistern anatomically and give the ranges of dimensions for proper radiological interpretation. The study was performed on 160 axial computed tomography (CT) examinations of Polish children of both sexes, aged 1-18 years, admitted to the hospital because of mild brain concussion. Pictures were made using a Siemens 8-row CT scanner, without contrast administration. We estimated distances at the level of the pons and midbrain, based on axial cross-sections, according to standard radiological protocol. The parameters included the width of the AC in its anterior and posterior part, the width of the tentorial notch, and the distance from the pons and sella. All measurements were analyzed statistically with StatSoft Statistica 8.0 software. The average width of the AC differs between age groups. It is greatest at 1-3 years (2.8 &#177; 0.6 mm) and lowest at 4-10 years (2.4 &#177; 0.6 mm). AC is more likely to be greater in its anterior part in boys. The distance from the sella to the pons is greatest in 1-3-year-old girls (6.9 &#177; 1.3 mm), and the tentorial notch is widest in the 15-18-year-old group (24.6 &#177; 2.4 mm). Dimensions of the AC correlate with intracranial reserve volume. This is particularly visible in the youngest children. Thin and narrow AC is not always a sign of raised intracranial pressure. It may be specific for the child&#8217;s age. (Folia Morphol 2010; 69, 2: 78-83
    corecore