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A congenital defect in the diaphragm, known as a Bochdalek hernia (BH), is a condition that allows herniation of the abdominal viscera into the thorax. BH is the most common type of congenital diaphragmatic hernia (CDH) and is typically detected on the left side. An ectopic kidney is a rare condition. An intra-thoracic ectopic kidney is an extremely uncommon condition. In adult patients, the presence of BH with an intra-thoracic kidney is extremely uncommon and is often a finding discovered unintentionally. A 51-year-old male patient presented to the outpatient unit of the pulmonology department. He stated that he had been suffering symptoms such as coughing, wheezing, and breathing difficulties for one year. A chest X-ray showed a well-defined radio-opaque lesion in the lower left zone. A computed tomography (CT) scan of the chest demonstrated a defect in the posterolateral region of the left hemidiaphragm, as well as herniation of the left kidney and retroperitoneal fat in the left hemithorax. The intra-thoracic ectopic kidney was found to be normal in size and showed normal attenuation and enhancement, with the contrast being promptly excreted into the pelvicalyceal system during CT urography. Due to the hernia's small size and lack of abnormalities on CT urography, the patient was recommended a conservative treatment. A follow-up examination was performed on the patient annually. Throughout the follow-up period, there was not a single episode of kidney-related issues. To avoid unwanted image-guided biopsies and surgical procedures, it is imperative to look for intra-thoracic kidneys in patients presenting with a thoracic mass or an elevated hemi-diaphragm.

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A carbon-based material with a broad scope of favourable developments is called graphene. Recently, a graphene nanoribbon with cove-edged was integrated by utilizing a bottom-up liquid-phase procedure, and it can be geometrically viewed as a hybrid of the armchair and the zigzag edges. It is indeed a type of nanoribbon containing asymmetric edges made up of sequential hexagons with impressive mechanical and electrical characteristics. Topological indices are numerical values associated with the structure of a chemical graph and are used to predict various physical, chemical, and biological properties of molecules. They are derived from the graph representation of molecules, where atoms are represented as vertices and bonds as edges. In this article, we derived the exact topological expressions of cove-edged graphene nanoribbons based on the graph-theoretical structural measures that help reduce the number of repetitive laboratory tasks necessary for studying the physicochemical characteristics of graphene nanoribbons with curved edges.

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We report crystal growth, AC and DC magnetic susceptibilities [χ(T, H)], magnetization [M(T, H)], and heat capacity [CP(T, H)] measurement results of GdSbTe single crystal. GdSbTe is isostructural to the confirmed nonmagnetic nodal-line semimetal ZrSiS of noncentrosymmetric tetragonal crystal structure in space group P4/nmm (No. 129), but it shows additional long-range antiferromagnetic spin ordering for the Gd spins of S = 7/2 below TN. Both χ(T, H) and CP(T, H) measurements confirm the existence of a long-range antiferromagnetic (AFM) spin ordering of Gd spins below TN ∼ 12 K, and an additional spin reorientation/recovery (sr) behavior is identified from the change of on-site spin anisotropy between Tsr1 ∼ 7 and Tsr2 ∼ 4 K. The anisotropic magnetic susceptibilities of χ(T, H) below TN clearly demonstrate that the AFM long-range spin ordering of GdSbTe has an easy axis parallel to the ab-plane direction. The field- and orientation-dependent magnetization of M(T, H) at 2 K shows two plateaus to indicate the spin-flop transition for H||ab near ∼2.1 T and a metamagnetic state near ∼5.9 T having ∼1/3 of the fully polarized magnetization by the applied field. The heat capacity measurement results yield Sommerfeld coefficient of γ ∼ 7.6(4) mJ/mol K2 and θD ∼ 195(2) K being less than half of that for the nonmagnetic ZrSiS. A three-dimensional (3D) AFM spin structure is supported by the ab initio calculations for Gd having magnetic moment of 7.1 µB and the calculated AFM band structure indicates that GdSbTe is a semimetal with bare density of states (0.36 states/eV fu) at the Fermi level, which is 10 times smaller than the measured one to suggest strong spin-fluctuation.

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We present a comprehensive tensorial characterization of second-harmonic generation from silicon nitride films with varying compositions. The samples were fabricated using plasma-enhanced chemical vapor deposition, and the material composition was varied by the reactive gas mixture in the process. We found a six-fold enhancement between the lowest and highest second-order susceptibility, with the highest value of approximately 5 pm/V from the most silicon-rich sample. Moreover, the optical losses were found to be sufficiently small (below 6 dB/cm) for applications. The tensorial results show that all samples retain in-plane isotropy independent of the silicon content, highlighting the controllability of the fabrication process.

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The anisotropic superconducting properties of PbTaSe2 single crystal is reported. Superconductivity with T c = 3.83 ± 0.02 K has been characterized fully with electrical resistivity ρ(T), magnetic susceptibility χ(T), and specific heat C p (T) measurements using single crystal samples. The superconductivity is type-II with lower critical field H c1 and upper critical field H c2 of 65 and 450 Oe (H⊥ to the ab-plane), 140 and 1500 Oe (H|| to the ab-plane), respectively. These results indicate that the superconductivity of PbTaSe2 is anisotropic. The superconducting anisotropy, electron-phonon coupling λ ep, superconducting energy gap Δ0, and the specific heat jump ΔC/γT c at T c confirms that PbTaSe2 can be categorized as a bulk superconductor.

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A waveguide laser in an ytterbium-doped tantalum pentoxide film is reported. The waveguide is formed of a rib of sputtered tantalum pentoxide on top of oxidized silicon with an over-cladding of silica. Emission at a wavelength of 1025 nm was achieved with an absorbed pump power threshold and slope efficiency of ≈29 mW and 27%, respectively, for a cavity formed by a high reflector mirror and an estimated 12% Fresnel reflection from the bare end-face at the output.

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In the title compound, C(21)H(20)FN(3)O(5), the the pyrrolidine ring makes dihedral angles of 84.91 (6) and 62.38 (7)° with the oxindole unit and the fluoro-phenyl ring, respectively. The pyrrolidine ring assumes an envelope conformation with the spiro C atom as the flap. The crystal packing features weak N-H⋯N and C-H⋯O hydrogen bonds.

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In the title compound, C(17)H(13)NO(2), the dihedral angle between the benzene and the phenyl ring is 65.92 (7)°. The carbonitrile side chain is almost linear, the C-C-N angle being 175.55 (14)°. The crystal structure is stabilized by inter-molecular C-H⋯O inter-actions.

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Selective excitation of whispering-gallery and bottle modes in a robust hollow-bottle optical microresonator, fabricated from a silica microcapillary by a pressure-compensated, "soften-and-compress" method, is demonstrated. Characteristic resonance spectra of bottle modes were obtained by using a tapered fiber coupled at different locations along the hollow bottle. The spectral characteristics (Q-factor, excitation efficiency) are shown to have high tolerance to angular misalignment of the tapered fiber. In addition, introduction of localized losses on the outer surface of the resonator results in selective clean-up of the transmission spectrum and superior performance. A theoretical analysis of modal turning points and associated resonant wavelengths is used to explain the mechanism of mode-suppression and the resultant spectral cleaning.

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RESUMEN

In the title compound, C(18)H(15)ClN(2)O(2), the five-membered isoxazole ring adopts an envelope conformation [the deviation of the N atom is 0.3154 (15) Å] and the six-membered pyran ring adopts a half-chair conformation. The mean plane through all atoms of the isoxazole ring forms dihedral angles of 47.98 (8)° with the mean plane of the chromene ring system and 75.10 (9)° with the chloro-benzene ring.

RESUMEN

In the title compound, C(19)H(18)N(2)O(2), the five-membered isoxazole ring adopts an envelope conformation and the deviation of the N atom from the mean plane of the isoxazole ring is -0.3256 (11) Å. The pyran ring adopts a half-chair conformation. The isoxazole ring forms dihedral angles of 44.07 (7) and 84.23 (7)° with the pyran and methyl-benzene rings, respectively. The mol-ecular structure is stabilized by weak C-H⋯π inter-actions.

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In the crystal structure of the title compound, C(17)H(15)NOS, the mol-ecules form centrosymmetric dimers through pairs of N-H⋯O hydrogen bonds. The seven-membered ring adopts a distorted half-chair conformation.

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In the title compound, C(20)H(20)FNO(3), the pyrrolidine and benzopyran rings adopt half chair and twisted half chair conformations, respectively. The carboxyl-ate group is almost perpendicular to the pyran ring [89.4 (1)°].

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Laser action has been demonstrated in chalcogenide glass microsphere. A sub millimeter neodymium-doped gallium lanthanum sulphide glass sphere was pumped at 808 nm with a laser diode and single and multimode laser action demonstrated at wavelengths between 1075 and 1086 nm. The gallium lanthanum sulphide family of glass offer higher thermal stability compared to other chalcogenide glasses, and this, along with an optimized Q-factor for the microcavity allowed laser action to be achieved. When varying the pump power, changes in the output spectrum suggest nonlinear and/or thermal effects have a strong effect on laser action.

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Previous work (Tull, E. J.; Bartlett, P. N.; Ryan, K. R. Langmuir 2007, 14, 7859; Tull, E. J.; Bartlett, P. N. Colloids Surf., A 2008, 327, 71) has demonstrated that, since convective forces have little influence over spheres in unstable sols, many conventional assembly techniques are ineffective for the organization of glassy spheres > or =5 microm in diameter into sparse patterns of interest for optoelectronic device applications. Carefully designed bifunctional substrates are required for both planar and "in cavity" assembly. In the present work, novel selective chemical modification of structured Ta2O5/glass substrates has been used to generate surfaces tailored to the assembly of glass microspheres from aqueous solution. Uniform arrays of 40-60 microm diameter glass spheres have been produced in pits of half-diameter depth, demonstrating the suitability of this technique for fabricating optical devices where light is coupled from a waveguide into the equator of a sphere. Individual aspects of the assembly process have been examined, and their influence over defect densities and the positioning of the assembled spheres is discussed.

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Evanescent coupling of light from glass channel waveguides into the whispering gallery modes of glass microspheres of radius 15?m and 100?m is studied experimentally at wavelengths near 1550 nm. Fitting the positions, widths and heights of resonances in the experimental spectra to the characteristic equation for microsphere modes and to universal coupled microresonator theory, we establish sphere radius and index, identify mode numbers, and determine losses. The results provide detailed information for the design of optical devices incorporating microsphere resonators in planar lightwave circuits.

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The propulsion of 3 microm polystyrene spheres along a subwavelength optical wire is demonstrated. Velocities in the range of 7-15 microm/s are observed. Simulations are carried out to evaluate the evanescent field at the waveguide-water suspension interface.

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Micro-resonators have attracted considerable attention as a potential geometry for photonic devices used in multiplexing, memory and switching. These all-optical-resonators allow light at certain wavelengths to build up in intensity allowing nonlinear effects to be seen for much lower input power than in a bulk material. We report here on microspheres made from gallium-lanthanum-sulphide glass. Spheres have been produced with diameters from less than 1 mum up to 450 microm, and we demonstrate a first measured quality factor of 8x10(4) at 1.55 microm, for a chalcogenide sphere diameter of 100 microm. We also predict an ultimate Q of up to 4x10(10) at 3 microm.

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