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Patients often present to the emergency department with loss of consciousness. The differential diagnosis of such condition may be difficult because of limited clinical information. The authors present a case of subarachnoid haemorrhage (SAH) with initial electrocardiographic (ECG) finding mimicking ST-segment elevation myocardial infarction (STEMI), which was confirmed to resolve in a follow-up study. Accurate and timely diagnosis of SAH-related ST-segment elevation was important, as the therapeutic strategy for SAH is completely different from that for STEMI. If the clinicians do not have other tools for diagnosis, the follow-up ECG may help us make a most possible diagnosis.

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To improve graphene-based multifunctional devices at nanoscale, a stepwise and controllable fabrication procedure must be elucidated. Here, a series of structural transition of bismuth (Bi) adatoms, adsorbed on monolayer epitaxial graphene (MEG), is explored at room temperature. Bi adatoms undergo a structural transition from one-dimensional (1D) linear structures to two-dimensional (2D) triangular islands and such 2D growth mode is affected by the corrugated substrate. Upon Bi deposition, a little charge transfer occurs and a characteristic peak can be observed in the tunneling spectrum, reflecting the distinctive electronic structure of the Bi adatoms. When annealed to ~500 K, 2D triangular Bi islands aggregate into Bi nanoclusters (NCs) of uniform size. A well-controlled fabrication method is thus demonstrated. The approaches adopted herein provide perspectives for fabricating and characterizing periodic networks on MEG and related systems, which are useful in realizing graphene-based electronic, energy, sensor and spintronic devices.

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We report a high-efficiency hard-X-ray resonator with inclined-incidence geometry. A beam incident at 36.87° with respect to [3 1 0] excites Bragg back diffraction along (12 4 0) at 14.4388 keV for resonance in a Si-based resonator to produce intense resonance fringes. The experimental results showed the visibility enhanced by nearly 30 times compared with normal incidence. Also numerical calculations of the inclined-incidence resonator demonstrate ultrahigh efficiency and extremely narrow resolving power (sub-meV) with low background. This geometry surpasses the intrinsic limits of normal-incidence crystal-based resonators and enables ultrahigh-resolution X-ray optics for X-ray diffraction, spectroscopy, and imaging applications.

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Unusual x-ray focusing effect is reported for parabolic curved multi-plate x-ray crystal cavities of silicon consisting of compound refractive lenses (CRL). The transmitted beam of the (12 4 0) back reflection near 14.4388 keV from these monolithic silicon crystal devices exhibits extraordinary focusing enhancement, such that the focal length is reduced by as much as 18% for 2-beam and 56% for 24-beam diffraction from the curved crystal cavity. This effect is attributed to the presence of the involved Bragg diffractions, in which the wavevector of the transmitted beam is bent further when traversing several curved crystal surfaces.

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Establishment and characterization of two cobia, Rachycentron canadum, cell lines derived from cobia brain (CB) and cobia fin (CF) are described. Caudal fin and brain from juvenile cobia were dissociated for 30 and 10 min, respectively, in phosphate-buffered saline containing 0.25% trypsin at 25 degrees C. The optimal culture condition for both dissociated cells (primary cell culture) was at 28 degrees C in Leibovitz-15 medium containing 10% foetal bovine serum. The cells have been sub-cultured at a ratio of 1:2 for more than 160 passages over a period of 3 years. Origin of the cultured cells was verified by comparison of their sequences of mitochondrial cytochrome oxidase subunit I genes (cox I) with the cox 1 sequence from cobia muscle tissue. The cell lines showed polyploidy. No mycoplasma contamination was detected. Susceptibility to grouper iridovirus was observed for the CB cell line but not the CF cell line. Both cell lines expressed green fluorescent protein after being transfected with green fluorescent reporter gene driven by the cytomegalovirus promoter.

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The X-ray back diffraction of (1240) in a monolithic two-plate silicon cavity occurs at photon energy 14.4388 keV, at which 24 beams are simultaneously excited. Based on the dynamical theory of X-ray diffraction, a theoretical approach has been developed for solving the fundamental equation of dynamical theory to investigate this back diffraction and the interference patterns generated by the Fabry-Perot-type resonance that produces intensity undulation in both transmitted and back-reflected beams. The section of dispersion surface and its associated linear absorption coefficients, wavefield intensities and excitation of mode are calculated. The calculated intensity distribution of the transmitted beam is in a good agreement with the observed one. Details about the interaction between the multiply diffracted X-rays and cavity resonant photons are also reported. Procedures of computer programming are also provided.

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X-ray diffraction from a growing film at an anti-Bragg point should exhibit bilayer oscillations caused by interference. In an experiment of TiN film growth by laser ablation onto sapphire, an unexpected beating envelope function is found to modulate the oscillations. The successive nodes and antinodes are identified with the development of new growth domains separated by one atomic layer in thickness. This effect allows atomic layer counting of the film thickness distribution. The results imply that the growth is not characterized by a continuum stochastic process, as usually assumed.

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BACKGROUND: Atrial fibrillation is commonly associated with dilated pulmonary veins. Stretch has been shown to have mechano-electrical effects. OBJECTIVE: To investigate whether stretch can increase the arrhythmogenic activity of the pulmonary veins. METHODS: The transmembrane action potentials were recorded from rabbit pulmonary veins before and after stretch (100 and 300 mg). Gadolinium and streptomycin (stretch-activated ion channel blockers) were each perfused into the pulmonary veins under a 300-mg stretch. RESULTS: Stretch (0, 100 and 300 mg) force dependently increased the incidence of spontaneous activity (22%, 48% and 83%; p<0.05), mean (standard deviation (SD)) firing rates of spontaneous activity (1.7 (0.2), 2.1 (0.3) and 3 (0.2) Hz; p<0.05) and incidence of early post-depolarisations (9%, 26% and 61%; p<0.05) and delayed post-depolarisations (0%, 4% and 30%; p<0.05) in 23 pulmonary veins. In the seven preparations with spontaneous activity after the 300-mg stretch, gadolinium (1, 3 and 10 mumol/l) decreased the incidence of spontaneous activity by 43%, 29% and 14%, respectively (p<0.05), and decreased the firing rate from 2.9 (0.1) Hz to 0.8 (0.4), 0.3 (0.1) and 0.1 (0.1) Hz, respectively (p<0.05). Streptomycin (10 and 40 mumol/l) decreased the incidence of spontaneous activity by 71% and 29%, respectively (p<0.05), and decreased the firing rate from 2.9 (0.1) Hz to 1.6 (0.4) and 0.5 (0.3) Hz, respectively (p<0.05). CONCLUSION: Stretch is an important factor in the electrical activity of the pulmonary vein. Stretch-induced arrhythmogenic activity of the pulmonary vein may contribute to the genesis of atrial fibrillation.

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The complications of concurrent chemoradiotherapy for nasopharyngeal carcinoma include dryness of mouth, sensorineural hearing loss, dental caries, trismus, pituitary dysfunction, myelitis, paralysis of cranial nerves IX-XII, massive neck fibrosis and pharyngeal wall necrosis. Tornwaldt's cyst formation after concurrent chemoradiotherapy for nasopharyngeal carcinoma has not been reported previously in the world literature. Tornwaldt's cyst, a persistent pharyngeal bursa, is found in about 3 per cent of the adult population, although the majority of these are asymptomatic. We describe the previously unreported complication of Tornwaldt's cyst formation after concurrent chemoradiotherapy for nasopharyngeal carcinoma.

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We employ angle-resolved photoemission to study the electronic structure of atomically uniform films of Ag grown on Ge(111). A new kind of quantum well state is observed near a specific emission direction away from the surface normal. In contrast with the usual quantum well state arising from electron confinement by specular reflections at the surface and interface of the film, the new kind involves retroreflections, or umklapp reflections, at the interface. It requires four reflections, instead of the usual two reflections, to complete a coherent interference path.

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X-ray back diffraction from monolithic two silicon crystal plates of 25-150 microm thickness and a 40-150 microm gap using synchrotron radiation of energy resolution DeltaE = 0.36 meV at 14.4388 keV clearly show resonance fringes inside the energy gap and the total-reflection range for the (12 4 0) reflection. This cavity resonance results from the coherent interaction between the x-ray wave fields generated by the two plates with a gap smaller than the x-ray coherence length. This finding opens up new opportunities for high-resolution and phase-contrast x-ray studies, and may lead to new developments in x-ray optics.

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Water temperature has a differential influence on the development of central neurotransmitter systems according to the developmental period in tilapia (Oreochromis mossambicus). Aromatase and oestrogen receptors (ERs) represent important components of the mechanism of brain differentiation. Gene expression of aromatase and ERs is modulated by neurotransmitters in the developing brain. In the present study, the quantitative reverse transcription-polymerase chain reaction method was used to investigate the effects of temperature on the ontogenetic expression of aromatase and ERs in the developing tilapia brain. Before day 10 posthatching, exposure to a higher temperature (32 degrees C) resulted in a significant increase in the expression of brain aromatase; conversely, a lower temperature (20 degrees C) resulted in a decrease. ERalpha expression was depressed in accordance with the decrease of temperature, but ERbeta was unaffected by temperature. Between days 10 and 20, neither brain aromatase nor ERalpha expression was altered by temperature, whereas ERbeta expression was significantly enhanced by exposure to 32 degrees C. Between days 20 and 30, brain aromatase significantly increased at the higher temperature and decreased at 20 degrees C, but neither ERalpha nor ERbeta was affected by temperature. The expression of both brain aromatase and ERs, differentially regulated according to the temperature and to the developmental period, could be related to brain-sex differentiation.

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The phenomenon of the polarization suppression of X-ray Umweg multiple waves in Renninger scans [Renninger (1937). Z. Kristallogr. 97, 107-121] of crystals, showing intensity decrease due to properly chosen wavelength and polarization of incident radiation, is observed. That is, one of the participating wave components in the multiple-wave interference is reduced considerably so that the intensity of multiple diffraction is decreased. The condition for total suppression of the multiple-wave interaction in crystals is derived theoretically from the Born approximation and verified with exact dynamical calculation and experiments. Partial suppression of the strong Umweg interfered component is demonstrated using elliptically or linearly polarized synchrotron radiation. The suppressed multiple-wave intensity distribution reveals high sensitivity to X-ray reflection phase. This multiple-diffraction technique under partial polarization suppression provides an alternative way of enhancing the visibility of multiple-wave interference in crystals for direct phase determination.

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Numerical calculation of the angular and spectral distributions of the intensities of the specularly diffracted waves in the case of three-wave grazing-incidence X-ray diffraction is carried out using the dynamical theory. The angular and spectral distributions are shown to be uniquely and continuously dependent upon the value of the triplet phase invariant. A method of determining the value of the triplet phase invariant for thin crystal surface layers is developed, based on the comparison of experimentally measured three-wave peak profiles with the profiles calculated for different values of the triplet phase invariant. An analysis scheme of the phase sensitivity of the reflection coefficients is proposed taking into account the interference of the directly excited and the 'Umweg'-excited specularly diffracted waves.

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A dynamical calculation scheme that employs Cartesian coordinates with a z axis normal to the crystal surface to define polarization unit vectors and wavefields is applied to interpret the intensity distribution of crystal truncation rods for surfaces and interfaces. A comparison between this calculation scheme and the asymptotic iteration approach using the conventional presentation of the polarization components of the wavefields, with the sigma and pi components perpendicular to the wavevectors, is presented. It is found that the use of Cartesian coordinate systems can provide correct boundary conditions in determining the wavefield amplitudes, thus leading to a rigorous and general calculation scheme for dynamical diffraction from surfaces and interfaces.

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A model for analysing the phase sensitivity of the reflection coefficients of a diffracted wave in the case of three-wave X-ray diffraction is proposed. This model considers three-wave diffraction as the interference of the directly excited and the Umweg-excited diffracted waves and seems to account properly for the phase sensitivity as well as the behaviour of an involved diffracted wave as a function of the triplet phase invariant, the polarization state of the incident wave and the diffraction geometry. The practical issues for phase determination are also considered.

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Without invoking anomalous dispersion and heavy-atom derivatives, it is demonstrated that it is possible to directly determine the phases of a large number of reflections collected in a short time from macromolecular crystals using a stereoscopic oscillation-crystal imaging technique, in a multibeam diffraction geometry, where two crystallographic axes in opposite directions are employed as the rotation axes. The intensity profiles (distributions) of the diffraction spots versus the varying tilt Bragg angle of the rotation axis in the two stereoscopically related images yield quantitative phase information. Many multiple diffraction profiles of tetragonal lysozyme and an unknown protein structure are obtained at the rate of 100 profiles per 30 min of X-ray exposure.