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Spontaneous spinal epidural hematoma (SSEH) refers to the occurrence of spontaneous bleeding into the epidural space of the spinal cord without trauma or any iatrogenic procedures that result in compressive myelopathy. It is a rare condition that presents with acute onset neck pain or back pain with neurological symptoms. Clinical presentation will be variable, and the occurrence of neurological symptoms may be delayed depending on the level and extent of involvement of the bleed. So, this condition can mimic many other diagnoses, and unless diagnosed and managed promptly, the patient will have a poor outcome. In this case report, we describe three cases that had varying presentations and were initially misleading. [ABSTRACT FROM AUTHOR]

This paper reports, for the "first time," the delayed response of O¹D 630.0 nm dayglow emissions over Trivandrum (8.5°N, 77°E, 0.5°N dip lat.), a geomagnetic dip equatorial station in India, to the noontime X-class solar flare event of July 30, 2005. The dayglow measurements were made using a unique dayglow photometer operating at three wavelengths. The Equatorial Electrojet induced magnetic field, measured using a proton precession magnetometer, showed a magnetic spike having ~90 nT enhancement during this flare with a time delay of ~7.2 min. A noteworthy observation is that unlike to the conventional belief, the O¹D 630.0 nm dayglow over the dip equator exhibited a fourfold enhancement during the noontime flare after a time delay of ~45 min. Analysis of satellite measured electron density and modeling simulations indicate that the thermospheric O¹D 630.0 nm dayglow emission over the dip equatorial region during a solar flare is primarily driven by the electrodynamics, rather than the direct solar control. This finding is new, unique and very important for the studies related to plasma-neutral coupling and also for modeling studies on the equatorial thermosphere-ionosphere region is concerned. [ABSTRACT FROM AUTHOR]

This paper reports, for the “first time,” the delayed response of O1D 630.0 nm dayglow emissions over Trivandrum (8.5°N, 77°E, 0.5°N dip lat.), a geomagnetic dip equatorial station in India, to the noontime X‐class solar flare event of July 30, 2005. The dayglow measurements were made using a unique dayglow photometer operating at three wavelengths. The Equatorial Electrojet induced magnetic field, measured using a proton precession magnetometer, showed a magnetic spike having ∼90 nT enhancement during this flare with a time delay of ∼7.2 min. A noteworthy observation is that unlike to the conventional belief, the O1D 630.0 nm dayglow over the dip equator exhibited a fourfold enhancement during the noontime flare after a time delay of ∼45 min. Analysis of satellite measured electron density and modeling simulations indicate that the thermospheric O1D 630.0 nm dayglow emission over the dip equatorial region during a solar flare is primarily driven by the electrodynamics, rather than the direct solar control. This finding is new, unique and very important for the studies related to plasma‐neutral coupling and also for modeling studies on the equatorial thermosphere‐ionosphere region is concerned.Key Points: This paper discusses an unusual and delayed response of O1D 630.0 nm dayglow emissions over the geomagnetic equator, during an X‐class flareAnalysis revealed that the dayglow emission over the dip‐equator during a flare is primarily driven by the equatorial electrodynamicsThe equatorial fountain brings the flare‐enhanced ionization from the lower F‐region to the emission centroid and increases the dayglow [ABSTRACT FROM AUTHOR]

Abstract: This study presents the influence of stratospheric sudden warming (SSW) events in modulating the start time of the equatorial spread‐F (ESF) through enhanced planetary wave (PW) activity during the winter months of the SSW years. The analysis based on the data from a digital ionosonde and proton precession magnetometer over Trivandrum (8.5°N, 77°E, 0.5°N dip lat.) revealed that the PWs of quasi‐16 day periodicity influence the start time of the ESF to a significant extent during the SSW years. On the other hand, during a normal year such effect is not very evidently present. It has been observed that the quasi‐16 day wave propagates to ionospheric dynamo region from the atmosphere below and modifies the electrodynamical processes like the equatorial electrojet and prereversal enhancement, which is more pronounced during both the SSW periods. Such a modification in the electrodynamics can modulate the equatorial plasma fountain and influence the F region neutral dynamics, which in turn can affect the occurrence of ESF by modifying the seeding conditions. [ABSTRACT FROM AUTHOR]