Resolution of holograms produced by the fluid experiment system and the holography ground system

The Fluid Experiment System (FES) was developed to study low temperature crystal growth of triglycine sulfate from solution in a low gravity environment onboard Spacelab. The first flight of FES was in 1985. FES uses an optical system to take holograms of the growing crystal to be analyzed after the mission in the Holography Ground System (HGS) located in the Test Laboratory at Marshall Space Flight Center. Microscopic observation of the images formed by the reconstructed holograms is critical to determining crystal growth rate and particle velocity. FES and HGS were designed for a resolution of better than 20 micrometers, but initial observation of the flight holograms show a limit of 80 micrometers. The resolution of the FES holograms is investigated, as well as the role of beam intensity ratio and exposure time on the resolution of HGS produced holograms

Quantitative Schlieren analysis applied to holograms of crystals grown on Spacelab 3

In order to extract additional information about crystals grown in the microgravity environment of Spacelab, a quantitative schlieren analysis technique was developed for use in a Holography Ground System of the Fluid Experiment System. Utilizing the Unidex position controller, it was possible to measure deviation angles produced by refractive index gradients of 0.5 milliradians. Additionally, refractive index gradient maps for any recorded time during the crystal growth were drawn and used to create solute concentration maps for the environment around the crystal. The technique was applied to flight holograms of Cell 204 of the Fluid Experiment System that were recorded during the Spacelab 3 mission on STS 51B. A triglycine sulfate crystal was grown under isothermal conditions in the cell and the data gathered with the quantitative schlieren analysis technique is consistent with a diffusion limited growth process

Studies on an inherited cataract of sheep : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University

The findings presented in this thesis comprise the first report and description of an inherited cataract in sheep. The condition was first diagnosed in a number of related New Zealand Romney sheep, from a high performance Romney stud. Clinically, cataracts which are always bilateral, are usually first visible at 2 months of age as characteristic focal opacities, confined to either the central or peripheral anterior and posterior cortex of the lens. By 8 to 10 months of age, there is more generalised lenticular opacity and total opacity usually occurs by 10 to 12 months. Two lambs born with congenital bilateral mature cataracts, showed partial lens absorption, which was obvious clinically by 8 months of age. Controlled breeding studies, show that cataracts are inherited as a simple autosomal dominant trait. The two congenitally affected lambs, which resulted from matings between affected parents, are assumed to be homozygous for the defective gene. Histologically, ovine cataract is characterised by the progressive degenerative swelling and lysis of lenticular fibres, beginning initially within localised areas of the anterior and posterior cortex. The distribution of early lesions correlates with the clinical appearance of early stage cataracts. With cataract progression, more of the cortical and eventually the nuclear fibres are affected and in the mature state, only a small number of attenuated equatorial fibres remain. The anterior epithelial cells become vacuolated apparently in response to cortical degeneration, and they also undergo proliferation, metaplasia to a spindle shaped cell and they migrate posteriorly beneath the posterior capsule. Beneath the posterior capsule, epithelial cells form either a single layer of flattened cells, or aggregations of large 'bladder' cells. The formation of new lens fibres at the equator continues relatively normally, throughout all stages of cataract. Ultrastructurally, anterior epithelial cells contain two types of vacuole. Small circular vacuoles which are not membrane bound are present in small groups within the cytoplasm. These are also present and are more numerous within spindle shaped cells. The large irregular shaped vacuoles noted by light microscopy are usually membrane bound and often contain membranous or granular material. These vacuoles are interpreted as being dilated and damaged endoplasmic reticulum. Both spindle shaped and vacuolated anterior epithelial cells have increased amounts of endoplasmic reticulum and in spindle shaped cells, fibrillar material and electrondense deposits are present. Capsular material, though observed surrounding some spindle shaped cells histologically, could not be demonstrated ultrastructurally. The profound breakdown of the cellular architecture of the lens is readily demonstrated by scanning electronmicroscopy. Water and electrolyte analyses of cataractous lenses, show that water and sodium content increases and potassium is lost, during cataractogenesis. The objectives of this study, were to define the inherited cataract of New Zealand Romney sheep in clinical, genetic and pathological terms, to examine water and electrolyte shifts in cataractous lenses, and to compare the condition with other inherited cataracts of man and other animals. It is concluded, that this ovine cataract though apparently clinically unique, does in pathological and biochemical terms resemble many cataracts of man and animals of different causes. These changes are not aetiologically significant, but merely reflect the limited range of stereotyped reactions which are possible in the cataractous lens. For this reason, it is proposed that this ovine cataract would provide a useful model for fundamental studies on the pathogenesis of cataract

Synthetic pathways of platinum(IV) 2-phenylpyridine halogenic derivatives as potential anticancer agents

Research Poste

Surveillance of Respiratory Hazards

journal articleBiomedical Informatic

Extended Duration Studies of Energetic Particles in the Stratosphere

The Balloon Assisted Stratospheric Experiments (BASE) program aims to measure atmospheric muon concentration at the Pfotzer Maximum with Geiger Counters carried by weather balloons. The most intense radiation is found at the Pfotzer Maximum 18 - 22 km (11 - 13 mi) above ground level. During this summer, seven flights were conducted to attain maximum time in the Pfotzer Maximum using different strategies like underfilling and multiple balloon systems

Orca network\u27s whale sighting network: citizen science and so much more

Orca Network’s Whale Sighting Network increases awareness of the Southern Resident orcas and other whales, and fosters a stewardship ethic to motivate a diverse audience to take action to protect Northwest waters. The Network provides hands-on opportunities for the public to report sightings of whales, gathering important data for researchers and encouraging shore-based whale watching and Be Whale Wise boating. The Network improves communication between researchers, agencies and the public, raising awareness about whales and related issues. As people become educated through the network, an ever-increasing amount of data is collected, and the public and researchers are able to share information and learn together about the issues affecting whales and how to better address them. The Sighting Network began informally in the late 1990s, via phone calls to a short list of volunteers. With the advent of email and Facebook, the Network has grown from a handful of people to an email list of 15,000 subscribers and a Facebook page reaching over 141,000 followers from the Pacific Northwest and around the world. Additional education is provided by volunteers on the shore watching whales, sharing their knowledge with local residents, and through displays, presentations and events, and our Langley Whale Center on Whidbey Island, WA. We have seen many changes in habitat use and occurrence of unusual species over the decades, most recently the historic decrease in use of Haro Strait by Southern Residents, and a marked increase in Transient/Bigg\u27s orcas and Humpback whales in Puget Sound and the Salish Sea. The Sighting Network has also actively worked with Stranding Networks and researchers in assisting to locate and track entangled whales or cetaceans out of their usual habitat. Sightings data collected through the Network has been cited in numerous research publications on Southern Resident and Transient/Bigg\u27s orcas, Humpbacks, Gray whales and Fin whales

Negative Ion Production Rates In Rare Gas-Halide Lasers

This paper reports on dissociative electron attachment in F2, NF3, Cl2, and I2. The principle of the method is to produce a short burst of photoelectrons from a photocathode by means of light from an argon-fluoride laser. Subsequently, by studying the motion of electrons and negative ions in a constant electric field (E) region, information is obtained about drift velocities and effective attachment cross sections. Helium, argon, and nitrogen were used as buffer gases. Of particular interest is a very strong temperature dependence of the attachment coefficient in I2. Measurements were taken from 35 to 110°C, covering an E/N range of 1-50 Townsend. An explanation based on vibrational excitation is presented. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc