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Traumatic posterior atlantoaxial dislocation without related fracture of the odontoid process is very rare, and only ten cases have been previously reported. The objective of this paper was to describe a case of traumatic posterior atlantoaxial dislocation without related fracture of the odontoid process, and its management with atlantoaxial transarticular screw fixation and bony fusion through an anterior retropharyngeal approach, and to review the relevant literature. The patient's medical and radiographic history is reviewed as well as the relevant medical literature. Posterior atlantoaxial dislocation was confirmed in a 48-year-old male struck by an automobile through conventional radiography, computed tomography and magnetic resonance imaging. No related fracture of the odontoid process or neurological deficit was found in this patient. Transarticular screw fixation of the atlantoaxial articulation through anterior retropharyngeal approach was performed after several unsuccessful attempts of closed reduction. At the latest follow-up, the lateral cervical spine radiography in flexion and extension demonstrated no instability of the atlantoaxial complex 21 months after the operation. In conclusion, patients with posterior atlantoaxial dislocation without fracture may survive with few or no-long term neurological deficit. Routine CT and MRI of the cervical spine should be carried out in patients with head or neck trauma to prevent missing of this rare clinical entity. Transarticular screw fixation of the atlantoaxial articulation through anterior retropharyngeal approach is safe and useful in case the management of dislocation is unsuccessful under closed reduction.

Six mitochondria/lysosomes self-targetable and viscosity-sensitive dyes (1a–1f) were developed via simple structure modification on cyanine-derived dyes. They all showed remarkable OFF–ON fluorescent response to viscosity in the near-infrared region (652–690 nm) and exhibited good linear relationship with solution viscosity. The transient absorption spectra were used to evaluate the excited-state lifetime of dye 1a in different viscosity environments. Furthermore, cellular imaging assays indicated that different derivatives (1a–1f) with the same chromophore core exhibited different organelle-targeting abilities. Among them, dyes 1a–1c could sense lysosomal viscosity fluctuations while dyes 1d–1f could be applied in mitochondrial viscosity detections.

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In order to strengthen the onshore transmission network in many parts of the world, VSC HVDC will increasingly be utilized. The effect of the operating point of a VSC HVDC link and the control strategies employed can substantially affect the electromechanical oscillatory behavior of the AC network as well as the DC side dynamics. In order that the full, flexible capability of VSC HVDC can be exploited, further study of the effects of these controllers and their interactions with AC system responses is necessary. This paper addresses this gap. Both modal analysis and transient stability analysis are used to highlight tradeoffs between candidate VSC-HVDC power controllers and to study the electromechanical performance of the integrated AC/DC model. Tests are carried out on both a generic two-area model and a large-scale realistic network with detailed AC generator and HVDC models.

The introduction of a benzene ring largely affects the excited-state absorption spectra and dynamics of these chromophores.

We study unconventional superconductivity in exfoliated single crystals of a promising three-dimensional (3D) topological superconductor candidate, Nb-doped Bi 2 Se 3 through differential conductance spectroscopy and magnetotransport. The strong anisotropy of the critical field along the out-of-plane direction suggests that the thin exfoliated flakes are in the quasi-2D limit. Normal metal-superconductor (NS) contacts with either high or low transparencies made by depositing gold leads onto Nb-doped Bi 2 Se 3 flakes both show significant enhancement in zero bias conductance and coherence dips at the superconducting energy gap. Such behavior is inconsistent with conventional Blonder−Tinkham−Klapwijk theory. Instead, we discuss how our results are consistent with p-wave pairing symmetry, supporting the possibility of topological superconductivity in Nb-doped Bi 2 Se 3 . Finally, we observe signatures of multiple superconducting energy gaps, which could originate from multiple Fermi surfaces reported earlier in bulk crystals.

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