Prospective study of surgical outcomes of cervical myelopathy based on its etiology, duration of affection and radiological patterns of compression

Background: Cervical spondylotic myelopathy (CSM) is considered the commonest cause of spinal cord dysfunction in individuals above 55 years of age and if left untreated, permanent cord damage may occur. This could contribute to increased dependence and reduced quality of life in older individuals. A prospective cohort study done in patients with cervical myelopathy who were admitted and operated after considering inclusion and exclusion criteria.Methods: A prospective cohort study done in patients with cervical myelopathy who were admitted and operated after considering inclusion and exclusion criteria. Total 30 patients included in study. patients were operated according to patterns of compression. Anterior/posterior decompression SOS instrumentation was done according to POC. Pre-op and post-op Nurick’s grading, pre-op and post-op modified Japanese orthopaedics association (mJOA) scores were used for comparison. Patients were followed up for period of 1 year from surgical intervention. Recovery rate calculated using preop and post op mJOA scores.Results: Overall satisfactory surgical outcome found in patients of cervical myelopathy, out of 30 patients, 9 patients of pattern of compression I (POC I) had  recovery rate (RR) of (91.6±7.8) , 8 patients of POC II had RR of (78.4±14.8), 6 patients of POC III had RR of (73.5±11.1), 4 patients of POC IV had RR of (74.9±29.2), 3 patients of POC IVv had RR of (80.4±4.1).the assessment of the final outcome was done using mJOA scoring system  and Nurick’s grading system.Conclusions: Anterior cervical discectomy and fusion (ACDF) for POC I (one- or two-level anterior cord compression) and POC II (one or two levels of anterior and posterior cord compression) give good surgical outcome. Cervical laminectomy and SOS instrumentation is recommended for POC III (3 levels of anterior cord compression), IV (3 or more levels of anterior compression and development of narrow canal with multiple posterior compression) and IV variant (similar to POC IV with one or two levels, being more significant than the others).earlier diagnosis, prompt radiological investigations, individualizing surgical protocol, proper surgical techniques and proper follow-up evaluation are key in management of patients of cervical myelopathy

Non-invasive Measurements of Cavity Parameters by Use of Squeezed Vacuum

We propose and experimentally demonstrate a method for non-invasive measurements of cavity parameters by injection of squeezed vacuum into an optical cavity. The principle behind this technique is the destruction of the correlation between upper and lower quantum sidebands with respect to the carrier frequency when the squeezed field is incident on the cavity. This method is especially useful for ultrahigh $Q$ cavities, such as whispering gallery mode (WGM) cavities, in which absorption and scattering by light-induced nonlinear processes inhibit precise measurements of the cavity parameters. We show that the linewidth of a test cavity is measured to be $\gamma = 844\pm40$ kHz, which agrees with the classically measured linewidth of the cavity within the uncertainty ($\gamma=856\pm34$ kHz).Comment: 6 pages, 4 figure

Calculation Of Pressure Rise And Energy Of Hot Gases Due To High Energy Arcing Faults In The Metal-clad Switchgear

This paper presents the 3-D CFD calculation results of the pressure rise due to the High Energy Arcing Faults (HEAFs) in the metal-clad switchgears. The calculations were performed considering the came-off of the roof panel that was observed in the arc tests. The calculated pressure development approximately agreed with the measured one. Furthermore, the energy of hot gases exhausted from the broken roof panel was calculated to investigate the thermal effect of hot gases

Isolation of gravitational waves from displacement noise and utility of a time-delay device

Interferometers with kilometer-scale arms have been built for gravitational-wave detections on the ground; ones with much longer arms are being planned for space-based detection. One fundamental motivation for long baseline interferometry is from displacement noise. In general, the longer the arm length L, the larger the motion the gravitational-wave induces on the test masses, until L becomes comparable to the gravitational wavelength. Recently, schemes have been invented, in which displacement noises can be evaded by employing differences between the influence of test-mass motions and that of gravitational waves on light propagation. However, in these schemes, such differences only becomes significant when L approaches the gravitational wavelength, and shot-noise limited sensitivity becomes worse than that of conventional configurations by a factor of at least (f L/c)^(-2), for f<c/L. Such a factor, although can be overcome theoretically by employing high optical powers, makes these schemes quite impractical. In this paper, we explore the use of time delay in displacement-noise-free interferometers, which can improve their shot-noise-limited sensitivity at low frequencies, to a factor of (f L/c)^(-1) of the shot-noise-limited sensitivity of conventional configurations.Comment: 10 pages, 12 figures, a proceeding for the Spanish Relativity Meeting ERE 200

Calculation of OPGW Strands Melting due to DC Arc Discharge Simulating High-Energy Lightning Strike

Metal strands of OPGWs (composite fiber-optic ground wires) installed in overhead power transmission lines are sometimes melted and broken when struck by high-energy lightning. This paper presents the calculation results regarding OPGW strands melting behavior when struck by DC arcs simulating high-energy lightning. The calculations revealed that the melted volume of the strand was 26% of the strand volume before the arc test, i.e. the rate of the non-melted volume of the strand was 74%. On the other hand, the residual tensile strength of the melted strand was 69% of the other non-melted strands after DC arc test. These results suggest there is a strong correlation between the calculated non-melted volume of the strand and the measured residual tensile strength of the melted strand

Role of phason-defects on the conductance of a 1-d quasicrystal

We have studied the influence of a particular kind of phason-defect on the Landauer resistance of a Fibonacci chain. Depending on parameters, we sometimes find the resistance to decrease upon introduction of defect or temperature, a behavior that also appears in real quasicrystalline materials. We demonstrate essential differences between a standard tight-binding model and a full continuous model. In the continuous case, we study the conductance in relation to the underlying chaotic map and its invariant. Close to conducting points, where the invariant vanishes, and in the majority of cases studied, the resistance is found to decrease upon introduction of a defect. Subtle interference effects between a sudden phason-change in the structure and the phase of the wavefunction are also found, and these give rise to resistive behaviors that produce exceedingly simple and regular patterns.Comment: 12 pages, special macros jnl.tex,reforder.tex, eqnorder.tex. arXiv admin note: original tex thoroughly broken, figures missing. Modified so that tex compiles, original renamed .tex.orig in source

Effects of mode degeneracy in the LIGO Livingston Observatory recycling cavity

We analyze the electromagnetic fields in a Pound-Drever-Hall locked, marginally unstable, Fabry-Perot cavity as a function of small changes in the cavity length during resonance. More specifically, we compare the results of a detailed numerical model with the behavior of the recycling cavity of the Laser Interferometer Gravitational-wave Observatory (LIGO) detector that is located in Livingston, Louisiana. In the interferometer's normal mode of operation, the recycling cavity is stabilized by inducing a thermal lens in the cavity mirrors with an external CO2 laser. During the study described here, this thermal compensation system was not operating, causing the cavity to be marginally optically unstable and cavity modes to become degenerate. In contrast to stable optical cavities, the modal content of the resonating beam in the uncompensated recycling cavity is significantly altered by very small cavity length changes. This modifies the error signals used to control the cavity length in such a way that the zero crossing point is no longer the point of maximum power in the cavity nor is it the point where the input beam mode in the cavity is maximized.Comment: Eight pages in two-column format. Six color figures. To be published JOSA

Damping Reduction Factors for Crustal, Inslab, and Interface Earthquakes Characterizing Seismic Hazard in Southwestern British Columbia, Canada

High-damping displacement spectra and corresponding damping reduction factors ( η) are important ingredients in seismic design and analysis of structures equipped with seismic protection systems, as well as in displacement-based design methodologies. In this study, we investigated η factors for three types of earthquake characterizing seismic hazard in southwestern British Columbia, Canada: shallow crustal, deep inslab, and interface subduction. We used a large and comprehensive database including records from recent relevant earthquakes, such as the 2011 Tohoku event. Our key observations were as follows: (1) there is negligible dependence of η on soil class; (2) there is significant dependence of η on the frequency content and duration of ground motions that characterize the different record types, and (3) η is dependent on period, particularly for inslab events. Period-dependent equations were proposed to predict η for damping ratios between 5% and 30% corresponding to the three event types.</jats:p

INFLUENCE OF PLANTING DATES AND SOME CHEMICAL SUBSTANCES ON ROOTING OF PHYTOLACCA DIOICA

The present study was carried out under plastic house conditions at the nursery of Zohria garden, Hort. Res. Inst., ARC, Cairo, Egypt throughout the two successive seasons of 2015 and 2016 to reveal the effect of planting dates (winter, spring, summer and autumn), some rooting promoters at different concentrations i.e. IBA, NAA, 2,4-D, catechol, cinnamic acid and tryptophan (alone or in combination) and their interactions on rooting of hard-to-root ornamental tree Phytolacca dioica.Results revealed thatplanting in spring increased rooting percentage (%) and root length (cm) in both seasons to the highest values. Treating the cuttings with IBA at 4000 ppm + NAA at 4000 ppm formulation resulted in the highest rooting percentage (%) in both seasons. Although there was no clear trend that could be observed from the obtained results, planting cuttings in either spring or autumn in addition to treating with IBA at 4000 ppm + NAA at 4000 ppm formulation increased rooting percentage (%) to the highest values.In conclusion, to achieve a successful vegetative propagation and to induce rooting on cuttings it is recommended to plant the cuttings in either spring or autumn in addition to treating with IBA at 4000 ppm + NAA at 4000 ppm formulation