Strong Correlation Effects of A-site Ordered Perovskite CaCu3Ti4O12 revealed by Angle-Resolved Photoemission Spectroscopy

We report angle-resolved photoemission spectroscopy (ARPES) results of A-site ordered perovskite CaCu$_3$Ti$_4$O$_{12}$. We have observed the clear band dispersions, which are shifted to the higher energy by 1.7 eV and show the band narrowing around 2 eV in comparison with the local density approximation calculations. In addition, the high energy multiplet structures of Cu 3$d^8$ final-states have been found around 8 - 13 eV. These results reveal that CaCu$_3$Ti$_4$O$_{12}$ is a Mott-type insulator caused by the strong correlation effects of the Cu 3$d$ electrons well hybridized with O 2$p$ states. Unexpectedly, there exist a very small spectral weight at the Fermi level in the insulator phase, indicating the existence of isolated metallic states.Comment: 5 pages, 5 figure

Magnetic excitations in a new anisotropic Kagom\'{e} antiferromagnet

The Nd-langasite compound contains planes of magnetic Nd3+ ions on a lattice topologically equivalent to a kagom\'{e} net. The magnetic susceptibility does not reveal any signature of long-range ordering down to 2 K but rather a correlated paramagnetism with significant antiferromagnetic interactions between the Nd and a single-ion anisotropy due to crystal field effect. Inelastic neutron scattering on Nd-langasite powder and single-crystal allowed to probe its very peculiar low temperature dynamical magnetic correlations. They present unusual dispersive features and are broadly localized in wave-vector Q revealing a structure factor associated to characteristics short range-correlations between the magnetic atoms. From comparison with theoretical calculations, these results are interpreted as a possible experimental observation of a spin liquid state in an anisotropic kagom\'{e} antiferromagnet.Comment: to appear in Physica

Taxonomy and identification of the armored dinoflagellate genus Heterocapsa (Peridiniales, Dinophyceae)

The armored dinoflagellate genus Heterocapsa is composed of relatively small species, including a species responsible for harmful red tides, H. circularisquama. Some Heterocapsa species such as H. rotundata and H. triquetra have been well documented as red tide-forming species, but are not recognized as causing harmful effects. Following sequential shellfish mass mortalities in the coastal waters of western Japan due to H. circularisquama red tides, this species has attracted considerable interest. Many properties of this species, such as its distribution and growth characteristics, have been investigated to better understand the mechanisms involved in harmful red tide formation. Related to the need for unambiguous identification of H. circularisquama, several unidentified (or undescribed) Heterocapsa species, which must be distinguished from the harmful taxon, have been detected sympatrically in regions where H. circularisquama blooms occur. However, the taxonomic affiliation of these Heterocapsa species have not yet been determined because several characteristics of Heterocapsa (e.g. body scale ultrastructure) have not yet been reported from all described species due to the changing taxonomic criteria. After the taxonomic ambiguities in this genus were resolved, cellular and body scale morphology of Heterocapsa were reinvestigated and several new species were described. In the present paper, the taxonomic history and morphological characters of the genus Heterocapsa are summarized

Mythic Narratives: The Chronicling of Conceptual Art

An exploration of the mythologized narratives that the work and lives of Conceptual artists Bas Jan Ader, Ana Mendieta, and Francis Alÿs have created and inspired. By virtue of their biographies, the fetishization of their personalities, and the ways in which this anecdotal information can be read in their work, mythologized narratives have been constructed, allowing for a prolonged interest existing within and without the confines of the art world. These mythologies come together as part of the oral tradition of the art world, a chronicling of narratives that incites continued interest for future generations

Redefining Diastolic Dysfunction Grading Combination of E/A ≤0.75 and Deceleration Time >140 ms and E/ε′ ≥10

AbstractObjectivesThis study sought to examine left atrial (LA) mechanics and the prognostic impact of patients with echocardiographic findings of E/A ratio ≤0.75, deceleration time (DcT) of mitral E-wave >140 ms, but E/ε′ ≥10.BackgroundTraditional diastolic dysfunction (DD) grading system could not classify every patient into a specific group. We considered the group of patients with E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 (proposed new DD grade) as a new group in the DD grading system.MethodsA total of 1,362 consecutive patients were stratified according to the new DD grading system, and the LA volumes, strain, and strain rates were measured by 2-dimensional speckle-tracking analysis. All patients were followed up to determine cardiac death and major adverse cardiac events.ResultsAn E/A ≤0.75, DcT >140 ms, but E/ε′ ≥10 was observed in 227 patients (17%). LA volumes in patients with the new DD grade were between those of the impaired relaxation group and the pseudonormal group. LA strain of the new DD grade was similar to that of the pseudonormal group, whereas LA booster function was preserved as in the impaired relaxation group. During a mean follow-up of 3.0 ± 1.1 years, 25 patients had cardiac death and 61 had major adverse cardiac events. Event-free survival for major adverse cardiac events of the new DD grade was worse than that of the impaired relaxation group but similar to that of the pseudonormal group.ConclusionsThe new DD grade is frequently observed and has a prognosis similar to that of the pseudonormal group but significantly worse than that of the impaired relaxation group. However, LA booster function was maintained at the expense of LA volume enlargement. Thus, the new grade should be a distinct entity for routine DD grading

Measurement of left atrial volume from transthoracic three-dimensional echocardiographic datasets using the biplane Simpson's technique.

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Putative genome features of relic green algaderived nuclei in dinoflagellates and future perspectives as model organisms

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