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Over the past decades a great deal of research effort has been devoted to understanding the physico-chemical mechanism of the dyeing of cotton with reactive dyes. However, the use of physico-chemical models has been almost exclusively restricted to research laboratories due to the simplifying assumptions used. A more practical model has now been developed and is intended to allow dyeing recipes and the process parameters used in bulk production to be optimised. The model is additionally able to quantify the effect of non-controllable variables on overall dyeing efficiency.

Data from 13 catchments with no arable land in Northern Scotland were used to develop empirical linear regression models of average monthly NO3 − concentrations and average summer and winter concentrations for NH4 +, dissolved organic N (DON) and dissolved organic carbon (DOC) as a function of catchment characteristics. All catchments displayed a pronounced seasonal NO3 − cycle. Variation in monthly mean NO3 − concentration within and between catchments could be predicted from mean monthly air temperature using separate regression equations for temperatures < and ≥ 5 °C. Soil type, climate and land use influenced NH4 + concentrations. In summer, concentrations of NH4 + were largest in catchments with extensive areas of brown forest soils, which are less acidic and more base-rich than other upland soils. However, concentrations declined with increasing conifer cover and summer rainfall. In winter, however, % conifer cover had a positive effect, while higher temperature and higher humus iron podzol cover had negative influences. DON concentration decreased with increasing catchment elevation in both summer and winter. Surprisingly, concentrations of DON only displayed a positive relationship with percentage peat cover in the summer. The most important factor controlling DOC concentration was soil type, with a positive relationship being observed between DOC and peat and humus iron podzol coverage. Elevation was also important, but only in the winter when concentrations were negatively correlated with maximum catchment elevation. Overall, multivariate regression equations explained the spatial and seasonal variability in N species concentrations over a range of catchments within Northern Scotland.

Previous work has shown that mGlu2/3 receptor agonists such as LY379268 inhibit motor responses to acutely administered phencyclidine (PCP) in rats. However, it has not been determined whether mGlu2/3 receptor agonists will reverse the enhanced effects of repeatedly administered PCP (so called PCP sensitization). In these studies, rats were administered daily PCP and monitored for the number of ambulations, fine movements, time at rest and rears using an automated activity system. At Day 10, when compared the first (Day 1) response, PCP-treated animals showed enhanced responses to all measures tested. Augmentations of these PCP-induced behaviors generally peaked between the third and tenth day after PCP administration had begun. Acute administration of LY379268 effectively suppressed PCP-evoked motor behaviors in rats sensitized to PCP. However, daily administrations of LY379268 (for 9 days), along with PCP, did not prevent the expression of the enhanced PCP response on Day 10. Thus, LY379268 administration can suppress PCP responses after either acute or chronic exposure to PCP. However, the underlying plasticity that leads to PCP sensitization was not affected by this treatment.

Dietary accumulation of four chiral organochlorine compounds--alpha-hexachlorocyclohexane (alpha-HCH), trans-chlordane, and chlorobiphenyls (CBs) 95 and 136-by immature rainbow trout (Oncorhynchus mykiss) was studied to determine if fish can accumulate and eliminate these compounds enantioselectively. Fish rapidly accumulated all four compounds from food spiked at micrograms per gram concentrations during a 40-d feeding period. Depuration half-lives were from 13 d for (+/-)-alpha-HCH to 375 d for (+/-)-CB 136. Fish preferentially eliminated (-)-trans-chlordane and (+)-CB 136, with significant nonracemic residues observed after 20 d. These results are consistent with field measurements of these compounds in fish as well as known metabolic pathways. Enantiomeric fractions (EFs) for these two compounds changed significantly over the course of the experiment, suggesting that trout were enantioselectively biotransforming the compounds during the 238-d depuration phase. CB 95 and alpha-HCH residues were racemic throughout the experiment. High biomagnification factors for CB 95 suggest that it was not metabolized. Minimum values for metabolic elimination rates calculated from EF suggest that at least 58% of the trans-chlordane depuration rate can be attributed to metabolism, and all of the CB 136 depuration rate can be attributed to it. This study highlights the potential of chiral analysis as a tracer of in vivo biotransformation processes of xenobiotic compounds.

Verification and Validation techniques will need to be adapted to address the unique challenges of developing autonomous systems. Looking towards the future, the question must be asked, how do we supplement traditional test and evaluation methods? In addition to new technology, what T&E workforce education requirements need to be addressed? As highly autonomous systems become more of a reality, trust in the system operation will transfer from the human operator to highly complex software and systems. Quantifying that trust and then providing a certification argument is a daunting task and an enabling technology for the transition of the next generation of autonomous systems. This report documents the year long study to identify, understand and categorize the unique challenges to the certification of safety critical autonomous systems by identifying the Verification and Validation (V&V) approaches needed to overcome them. The desired end state is to have a document categorizing the challenges into 3-6 thrust areas with a semi-detailed list of complementary approaches to address each challenge. The outcome of this study supports the AFRL Autonomy S&T strategy as well as provides input to the DoD Autonomy TEV&V Portfolio.

The stroke system of care is undergoing significant evolution. There are promising data to suggest that with new technologies and approaches, primary prevention and community education will become easier and more accessible, and will allow people to have greater participation in their own healthcare. The evidence-based primary and comprehensive stroke center concepts have been translated into robust, rapidly growing certification programs. The continued dissemination of improved EMS routing protocols allows for better allocation of patients to stroke centers, even as we confront the challenge of further improving prehospital recognition of stroke. National quality improvement initiatives help to ensure that patients directed to stroke centers receive evidence-based treatment, which has resulted in improved stroke care and better clinical outcomes. In remote areas, the use of technologies such as telemedicine to extend the reach of vascular neurologists has resulted in increased administration of time-sensitive thrombolytic therapy and better patient outcomes, although greater efficiency within the stroke system will likely be needed to realize the potential benefits of endovascular therapy. System-level paradigms for aggressive medical management promise to lessen the burden of recurrent stroke. Finally, further integration of rehabilitation programs into stroke centers and coordination with community-based rehabilitation services is needed to ensure the best possible outcome for stroke patients.

This paper presents the application of the Microsoft Kinect sensor for low-cost color-based real-time target tracking for robotic application. The image color and depth measurements from the Kinect sensor are utilized in identifying and localizing the target object and tracking it. Closed loop proportional-integral (PI) control algorithm is implemented to control a mobile robot for a smooth tracking of the target object. The iRobot Create is used as the development platform for the experiments. The voice recognition feature of the Kinect sensor is also accessible for simplifying the robot-human interaction when commanding the robot to track specific colored objects. Preliminary results of successful implementation of the real-time color tracking technique is demonstrated by letting the robot identify and track target objects with specified colors.

This dissertation investigates attitude transition maneuvers of a gyrosat-satellite between relative equilibria. The primary challenge in transitioning between relative equilibria is the proper adjustment of the system angular momentum so that upon completing the transition maneuver the gyrostat-satellite will satisfy all the requirements for a relative equilibrium. The system angular momentum is a function of the attitude trajectory taken during the transition maneuver. A new concept, the constant orbital momentum equilibrium trajectory or COMET, is introduced as a means to a straight-forward solution to a subset of the possible transitions between relative equilbria. COMETs are a class of paths in SO(3) that a gyrostat-satellite may travel along that maintain a constant system angular momentum. The primary contributions of this dissertation are the introduction and analysis of COMETs and their application to the problem of transitioning a gyrostat-satellite between two relative equilibria. The current work introduces, defines, and analyzes COMETs in detail. The requirements for a path in SO(3) to be a COMET are defined. It is shown via example that COMETs are closed-curves in SO(3). Visualizations of families of COMETs are presented and discussed in detail. A subset of COMETs are shown to contain critical points that represent isolated relative equilibrium attitudes or furcations of the COMET. The problem of transitioning between two relative equilibria is split into the sub-problems of transitioning between relative equilibria on the same COMET and transitioning between relative equilibria on different COMETs. For transitions between relative equilibria on the same COMET, an open-loop control law is developed that drives a gyrostat-satellite along the COMET until the target relative equilibrium is reached. For transitions between relative equilibria on different COMETs, an open-loop control law is developed that transfers a gyrostat-satellite from the initial relative equilibrium to a relative equilibrium that resides on the same COMET as the target relative equilbrium. Acquisition of the target relative equilibrium is then accomplished via the application of the open-loop control law for transitions between relative equilibria on the same COMET. The results of numeric simulations of gyrostat-satellites executing these transitions are presented. Ph. D.