Halogen occultation experiment (HALOE) optical witness-plate program

An optical witness plate program was implemented to monitor buildup of molecular contamination in the clean room during the assembly and testing of the Halogen Occulation Experiment (HALOE) instrument. Travel plates to monitor molecular contamination when the instrument is not in the clean room are also measured. The instrument technique is high-resolution transmission spectroscopy in the 3 micron spectral region using a Fourier transform spectrometer. Witness specimens of low index of refraction, infrared transmitting material are used for contaminant monitoring and for spectral signature analysis. Spectral signatures of possible molecular contamination are presented. No condensible volatile material contamination of HALOE optical witness specimens have yet been found

Audiogenic reflex seizures in cats

This study aims at characterizing feline audiogenic reflex seizures (FARS). An online questionnaire was developed to capture information from owners with cats suffering FARS. This was collated with the medical records from the primary veterinarian. Ninety-six cats were included. Myoclonic seizures were one of the cardinal signs of this syndrome (90/96), frequently occurring prior to generalized tonic-clonic seizures (GTCS) in this population. Other features include a late-onset (median 15 years) and absence seizures (6/96), with most seizures triggered by high frequency sounds amid occasional spontaneous seizures (up to 20%). Half the population (48/96) had hearing impairment or were deaf. One third of cats (35/96) had concurrent diseases, most likely reflecting the age distribution. Birmans were strongly represented (30/96). Levetiracetam gave good seizure control. The course of the epilepsy was non-progressive in the majority (68/96) with an improvement over time in some (23/96). Only 33/96 and 11/90 owners respectively felt the GTCS and myoclonic seizures affected their cat’s quality of life (QoL). Despite this, many owners (50/96) reported a slow decline in their cat’s health becoming less responsive (43/50), not jumping (41/50), uncoordinated or weak in the pelvic limbs (24/50), and exhibiting dramatic weight loss (39/50). These signs were exclusively reported in cats experiencing seizures for >2 years with 42/50 owners stating these signs affected their cat’s QoL. In gathering data on audiogenic seizures in cats, we have identified a new epilepsy syndrome named FARS with a geriatric-onset. Further studies are warranted to investigate potential genetic predispositions to this condition

MAGMO: Coherent magnetic fields in the star forming regions of the Carina-Sagittarius spiral arm tangent

We present the pilot results of the `MAGMO' project, targeted observations of ground-state hydroxyl masers towards sites of 6.7-GHz methanol maser emission in the Carina-Sagittarius spiral arm tangent, Galactic longitudes 280 degrees to 295 degrees. The `MAGMO' project aims to determine if Galactic magnetic fields can be traced with Zeeman splitting of masers associated with star formation. Pilot observations of 23 sites of methanol maser emission were made, with the detection of ground-state hydroxyl masers towards 11 of these and six additional offset sites. Of these 17 sites, nine are new detections of sites of 1665-MHz maser emission, three of them accompanied by 1667-MHz emission. More than 70% of the maser features have significant circular polarization, whilst only ~10% have significant linear polarization (although some features with up to 100% linear polarization are found). We find 11 Zeeman pairs across six sites of high-mass star formation with implied magnetic field strengths between -1.5 mG and +3.8 mG and a median field strength of +1.6 mG. Our measurements of Zeeman splitting imply that a coherent field orientation is experienced by the maser sites across a distance of 5.3+/-2.0 kpc within the Carina-Sagittarius spiral arm tangent.Comment: 19 pages, 13 figures, accepted for publication in MNRA

Ephemeral active regions and coronal bright points: A solar maximum Mission 2 guest investigator study

A dominate association of coronal bright points (as seen in He wavelength 10830) was confirmed with the approach and subsequent disappearance of opposite polarity magnetic network. While coronal bright points do occur with ephemeral regions, this association is a factor of 2 to 4 less than with sites of disappearing magnetic flux. The intensity variations seen in He I wavelength 10830 are intermittent and often rapid, varying over the 3 minute time resolution of the data; their bright point counterparts in the C IV wavelength 1548 and 20 cm wavelength show similar, though not always coincident time variations. Ejecta are associated with about 1/3 of the dark points and are evident in the C IV and H alpha data. These results support the idea that the anti-correlation of X-ray bright points with the solar cycle can be explained by the correlation of these coronal emission structures with sites of cancelling flux, indicating that, in some cases, the process of magnetic flux removal results in the release of energy. That the intensity variations are rapid and variable suggests that this process works intermittently