Measurement of trace stratospheric constituents with a balloon borne laser radar

The objective of this research was to measure the concentration of the stratospheric hydroxyl radical and related chemical species as a function of altitude, season, and time of day. Although hydroxyl plays a very important role in the chemistry controlling stratospheric ozone, little is known about its behavior because it has been a difficult species to measure. The instrument employed in this program was a laser radar, employing the technique of remote laser induced fluorescence. This instrument offers a number of attractive features including extreme specificity and sensitivity, a straightforward relationship between observed quantity and the desired concentration, and immunity to self-contamination

Functional properties and pharmacology of extrasynaptic GABA-A receptors

The “ambient” GABA that is present in the extracellular space surrounding all neurons of the brain is believed to be capable of persistently activating high‐affinity extrasynaptic GABA-A receptors to generate a tonic membrane conductance. This generates a form of shunting inhibition that is capable of influencing cellular and network excitability. Extrasynaptic δ subunit-containing GABA-A receptors are known to generate this form of tonic inhibition in a number of defined brain regions and these are emerging as important clinical drug targets for the treatment of a number of neurological conditions. This thesis examines the functional and pharmacological properties of recombinant and native GABA-A receptors that allow them to function as ambient GABA detectors. Surprisingly, the data presented in this Thesis shows that the behaviour of these extrasynaptic GABA-A receptor populations is dramatically influenced by the steady-state GABA concentration they experience. For example, recombinant α4βδ and α6βδ receptor populations are shown to exhibit profound levels of desensitization in the presence of low ambient GABA levels that will limit their ability to respond to changes in ambient GABA. We also find that the action of certain sedative/hypnotic drugs on extrasynaptic GABA-A receptors expressed in cerebellar granule neurons is critically dependent upon the concentration of ambient GABA. For example, we show that the intravenous anaesthetic propofol will only enhance tonic inhibition when ambient GABA levels are below 100 nM. Similarly, we show that the GABA-A receptor agonist Gaboxadol is not capable of enhancing tonic inhibition when ambient GABA levels are high. In contrast to the behaviour of drugs like propofol and Gaboxadol, we find that neurosteroid enhancement of tonic inhibition will occur regardless of ambient GABA levels. This issue will be important when considering therapeutic strategies to target tonic inhibition in the treatment of neurological disorders. Furthermore, we show for the first time, that copper ions can potently block extrasynaptic GABA-A receptors, suggesting that copper may provide a means to selectively block tonic inhibition in the brain, and may even represent a novel source of extrasynaptic GABA-A receptor modulation in vivo

Charles Gore and the Theology of Priesthood

The following dissertation is an investigation into the constitutive elements of a theology of priesthood to be found within the work of Charles Gore. Looking at Gore’s thought over a whole range of theological areas, this dissertation advances Gore’s theology of priesthood and develops his rich theological legacy with fresh insight into what he suggests the ordained priesthood may be called to be and do. As such it uncovers how the theology of priesthood is tied into Gore’s entire theological vision, connecting to his accounts of the Church, the sacraments and the incarnation. It uncovers fresh aspects to Gore’s understanding of the Church and its ministerial orders

Laboratory spectroscopy in support of atmospheric measurements

Optical measurements of trace species in the atmosphere require precise, accurate spectroscopic data for the molecules under study. This laboratory exits to provide high quality spectroscopic data for the interpretation of data from existing satellite, balloon, ground, and aircraft instruments, as well as to provide sufficient data to assess the feasibility of new instruments

Ground-based lidar measurements of stratospheric ozone. The NASA/GSFC stratospheric ozone lidar trailer experiment STROZ LITE

The major research objective is the measurement of high precision vertical profiles of ozone between 20-40 kilometers. The precision is such that the instrument should be capable of detecting a small trend (on the order of less that 1 percent per year) over a 5-10 year period. Temperature was measured between 30 and 365 km. The Goddard Space Flight Center (GSFC) mobile lidar was installed at Table Mountain and a comparison between it and the permanent Jet Propulsion Laboratory (JPL) lidar was made over the course of about 3 weeks. The lidars agreed very well between 20 and 40 km, and under certain conditions up to 45-47 km. There were several anomalies that both lidars followed very well. Agreement with Rocket Ozonesonde (ROCOZ) and electrochemical concentration cell (ECC) sondes was also very good

Artificial Teeth for Permanent Implantation

Artificial teeth with a low solubility and with properties similar to natural teeth were produced for implantation tests. The teeth were made from MgAl2O4 spinel and Ca3(PO4)2 Whitlockite to achieve low solubility and non-toxic reaction products. The method of manufacture is described

Canadian Ballads, and Occasional Verses

https://commons.und.edu/settler-literature/1143/thumbnail.jp

Stabilization of Lime with a Protective Glass Coating

The persistent hydration of lime has severely limited its use as a refractory material. Its hydration is somewhat retarded, but not prevented by heat treatment. A number of investigators have attempted to stabilize lime with chemical additions and have met with limited success. In this investigation an attempt has been made to stabilize lime by introducing a protective coating of glass and by hot pressing to reduce the porosity. Powdered refractory glasses and granular lime were hot pressed in a graphite mold at temperatures ranging from 1250 to 1450°C. The glasses were: 1) calcium-aluminate, 2) alumina-silicate and 3) aluminophosphate. Samples pressed with the alumino-silicate glass showed poor bonding and disintegrated when removed from the mold. Samples made with the calcium-aluminate and the alumino-phosphate glass showed good resistance to hydration when exposed to the atmosphere. Samples pressed with the calcium-aluminate glass at 1450°C withstood immersion in water at room temperature for 72 hours without disintegration