BACKGROUND The causes of upper extremity radicular pain or neck pain are varied, often involving disc herniation, spinal stenosis, or spondylosis. Cervical transformaminal epidural steroid injection (C-TFESI) is a common treatment for such pain. However, its efficacy conceivably may depend on needle-tip placement, linking the degree of pain reduction achieved to the pattern of contrast dispersi...

how to cite this article: movahedian ah, heidarzadeh arani m, motaharizad m, mousavi gha, mosayebi z. evaluation of qt dispersion in children with breath holding spells. iran j child neurol. winter 2016; 10(1):25-30. abstract objective breath holding spells (bhs) are common involuntary reflexes in infancy and early childhood. differential diagnosis should embrace long qt syndrome (lqts) and par...

Dispersion management (DM), optical phase conjugation (OPC), and the combination of DM and OPC are promising techniques to compensate for optical signal distortion due to group velocity dispersion and nonlinear Kerr effects. The system performance improvement in DM links combined with OPC has been reported; however, the fixed residual dispersion per span (RDPS) usually used in these links restr...

We analyze seismic data using multi-channel analysis of surface waves (MASW) to invert multi-mode surface-wave dispersion curves into 1D vertical shear-wave velocity profiles. The dispersion-curve patterns of the Rayleigh wave are imaged using conventional methods and the high-resolution linear radon transform (HRLRT). Comparison of these imaging techniques shows that the HRLRT provides higher ...

INTRODUCTION: In WDM soliton systems, the main sources of timing jitter (TJ) include the Gordon-Haus (GH) effect, soliton-soliton collisions (SSC), the acoustic effect, and the polarization mode dispersion. Although TJ from the GH effect is random from pulse to pulse, other sources lead to nonrandom TJ. Because the time displacements from the nonrandom sources highly depend on the pattern of tr...

A golden spiral photonic crystal fiber (GS-PCF) design is presented in which air holes are arranged in a spiral pattern governed by the golden ratio, where the design has been inspired by the optimal arrangement of seeds found in nature. The birefringence and polarization properties of this fiber are analyzed using a vectorial finite-element method. The fiber that is investigated shows a large ...

solid dispersions in water-soluble carriers have attracted considerable interest as a means of improving the dissolution rate, and hence possibly bioavailability, of a range of hydrophobic drugs. the poor solubility of carvedilol leads to poor dissolution and hence variation in bioavailability. the purpose of the present investigation was to increase the solubility and dissolution rate of carve...

background anthracyclines are important components of many chemotherapeutic protocols. the present study aimed to evaluate the repolarization changes in electrocardiography (ecg) which may predict drug induced arrhythmia. materials and methods in this cross-sectional study, the recorded ecgs were assessed for qt dispersion (qtd), qt corrected dispersion (qtcd), t peak to tend dispersion (tped),...

Taylor dispersion is a key concept in many fields. In the present paper, we characterize the pattern of the complete spatial concentration distribution for laminar tube flow; the obtained simple description is shown to represent the nature of Taylor dispersion. Importantly, we find that during the approach to the longitudinal normality of the transverse mean concentration at the time scale of R...