4,4′-Bipyridine-1,1′-diium 2,3,5,6-tetra­bromo­terephthalate dihydrate

The title compound, C10H10N2 2+·C8Br4O4 2−·2H2O, consists of a tetra­bromo­terephthalate dianion, a 4,4′-bipyridinium dication and two solvent water mol­ecules. Crystallographic inversion centers are situated at the center of the aromatic ring of the dianion as well as at the midpoint of the carbon–carbon bond connecting the pyridine rings in the dication. In the crystal, inter­molecular N—H⋯O hydrogen-bonding inter­actions between tetra­bromo­terephthalate dianions and protonated 4,4′-bipyridinium dications result in the formation of a chain-like structure. Further O—H⋯O hydrogen bonds between carboxyl­ate O atoms and water mol­ecules lead to the formation of a two-dimensional network in the crystal structure

Circularly-Polarized Light Emission from Semiconductor Planar Chiral Photonic Crystal

We proposed and demonstrated a scheme of surface emitting circularly polarized light source by introducing strong imbalance between left- and right-circularly polarized vacuum fields in an on-waveguide chiral grating structure. We observed circularly polarized spontaneous emission from InAs quantum dots embedded in the wave guide region of a GaAs-based structure. Obtained degree of polarization reaches as large as 25% at room temperature. Numerical calculation visualizes spatial profiles of the modification of vacuum field modes inside the structure with strong circular anisotropy.Comment: REVTeX4.1, 6pages, 3figure

Zero-cell photonic crystal nanocavity laser with quantum dot gain

We demonstrate laser oscillation in a hexagonal-lattice photonic crystal nanocavity using an InGaAs quantum dot gain material by optical pumping at 5 K. The cavity comprises a defect created by shifting several air holes in a two-dimensional photonic crystal slab structure without removing any air holes to achieve both small mode volume and a high cavity quality factor. The measured cavity quality factors and estimated mode volume for the nanocavity are ~33,000 and ~0.004 um^3. The laser threshold is compared between the zero-cell and L3-type nanocavity lasers, and the zero-cell nanolasers are found to have small thresholds of about one-third of the L3-type nanolasers. This result suggests that a higher Purcell factor of the zero-cell nanolaser is reflected as a smaller laser threshold.Comment: 6 pages, 3 figure

Poly[[dodeca­aqua­(μ4-benzene-1,4-dicarboxyl­ato)(μ2-4,4′-bipyridine-κ2 N:N′)dicerium(III)] bis­(benzene-1,4-dicarboxyl­ate)]

The asymmetric unit of the title compound, {[Ce2(C8H4O4)(C10H8N2)(H2O)12](C8H4O4)2}n, consists of half a CeIII cation, a quarter of a coordinated benzene-1,4-dicarboxyl­ate (bdc2−) dianion, a quarter of a 4,4′-bipyridine (bpy) mol­ecule, three water mol­ecules and a half of an uncoordinated benzene-1,4-dicarboxyl­ate dianion. The CeIII ion is located on a twofold rotation axis and exhibits a distorted trigonal prism square-face tricapped coordination geometry. The coordinated and uncoordinated bdc2− ions and the bpy mol­ecule lie about special positions of site symmetries 2/m, m and 2/m, respectively. The CeIII ions are bridged by the bdc2− and bpy ligands, giving a sheet structure parallel to the ac plane. The uncoordinated bdc2− dianion exists between the sheets and links the sheets by inter­molecular O—H⋯O hydrogen bonds between the uncoordinated bdc2− and coordinated water mol­ecules. A π–π stacking inter­action between the uncoordinated bdc2− dianion and the bpy ligand [centroid–centroid distance = 3.750 (4) Å] is also observed

Extracting Innovative Buyers by Scoring Using Innovator Theory

For companies that want to sell a high volume of products, it is important to identify innovative buyers to help with product marketing efforts. The purpose of this paper is to construct a model extracting whether users are innovative buyers or not from their purchase histories at physical stores and from access logs from an online-to-offline (O2O) site. Innovative buyers are users who influence other users' product purchases, also known in innovator theory as innovators and early adopters. They purchase products quickly, visiting physical stores such as supermarkets and convenience stores. In other words, innovative buyers are known to have high cosmopolite natures. In extracting innovative buyers, we estimated the speed of user product purchases and their cosmopolite natures. This estimation index can also be referred to as innovator scores. We went on to verify this method with socioeconomic status points, personality points and communication points (SPC points), using consciousness data and profile data collected from a panel on an O2O site. Thus, we showed that innovative buyers could be extracted using this new method, and the accuracy was higher than that of traditional methods measuring only the speed from product sale start to user purchase. Keywords: Innovator Scores, Innovative Buyers, SPC Points, O2O, Cosmopolite Natures, Extraction Model JEL Classifications: M31, O39, C38 DOI: https://doi.org/10.32479/irmm.981

Colorectal Carcinoma: Local Tumor Staging and Assessment of Lymph Node Metastasis by High-Resolution MR Imaging in Surgical Specimens

Purpose. To assess the accuracy of high-resolution MR imaging as a means of evaluating mural invasion and lymph node metastasis by colorectal carcinoma in surgical specimens. Materials and Methods. High-resolution T1-weighted and T2-weighted MR images were obtained in 92 surgical specimens containing 96 colorectal carcinomas. Results. T2-weighted MR images clearly depicted the normal colorectal wall as consisting of seven layers. In 90 (94%) of the 96 carcinomas the depth of mural invasion depicted by MR imaging correlated well with the histopathologic stage. Nodal signal intensity on T2-weighted images (93%) and nodal border contour (93%) were more accurate than nodal size (89%) as indicators of lymph node metastasis, and MR imaging provided the highest accuracy (94%–96%) when they were combined. Conclusion. High-resolution MR imaging is a very accurate method for evaluating both mural invasion and lymph node metastasis by colorectal carcinoma in surgical specimens

Bis[μ-3,5-bis­(2-pyrid­yl)pyrazolato]bis­(hydrogensulfato)­dicopper(II) methanol disolvate

The title compound, [Cu2(C13H9N4)2(HSO4)2]·2CH3OH, consists of discrete centrosymmetric dinuclear complex mol­ecules and methanol solvent mol­ecules. The CuII atom shows a square-pyramidal coordination geometry and is bonded to four N atoms of the two bis-chelating 3,5-bis­(2-pyrid­yl)pyrazol­ate ions (bpypz−) and one O atom of the hydrogensulfate ion. The bpypz− ligands in the complex mol­ecule are virtually coplanar [dihedral angle between the mean ligand planes = 0.000(1)°] with the CuII atom deviating in opposite directions from their best plane by 0.2080 (12) Å. π–π stacking inter­actions between the pyridyl and pyrazole rings [centroid–centroid distance = 3.391 (3) Å] and strong O—H⋯O hydrogen bonds between the hydrogensulfate ligands and the methanol mol­ecules assemble the mol­ecules into a one-dimensional polymeric structure extending along the a axis. The methanol mol­ecule acts both as an accepter and a donor in the hydrogen bonding