Irrigated agriculture's future in central Arizona is dependent upon the availability of two relatively fixed and limited resources: land and water. Adjustments within the agricultural sector will flow directly from, or in response to, changes in the availability and/or costs of these production factors. This study explores the agricultural use of these two factors of production and adjustments that will follow from their changing availability and cost over a 53-year period from 1967 to 2020. The area of central Arizona under study encompasses two irrigation districts-- the Salt River Project (SRP) and the Roosevelt Water Conservation District (RWCD). A structural model of the agricultural sector was synthesized from a survey of 102 operating farms in the study area. Models of four farm sizes were employed in a linear programming analysis to depict economies of scale. All four models were used to represent SRP farms, while two were used to represent RWCD farms. These farm models were held constant throughout the projection period, except for specified changes in the number of acres represented by each model (a decrease in land availability) in the SRP and the increasing water cost with which they are confronted in the RWCD. All other changes and/or adjustments wIthin agriculture are, in this analysis, dependent upon these land availability and water cost factors. Agricultural land and irrigation district surface and groundwater availability are considered factors exogenous to the agricultural sector. In the SRP, land and its appurtenant water rights have been and will continue over the projection period to flow into the urban-industrial sector at the expense of the agricultural sector. The cost of obtaining groundwater will increase over the projection period as the groundwater table declines. This increasing cost of groundwater will affect adjustments in agriculture in the SRP only slightly since water is provided to agriculture primarily through a user's cooperative which has excess electrical power revenues available to subsidize water prices to farmers. Increasing water costs in the RWCD will have a considerable affect on adjustments in agriculture because of the absence of revenue from any source to subsidize the cost of obtaining groundwater. Land availability is assumed constant in this district and, therefore, is of no significance in adjustments that occur over the projection period. Acreages of crops producing high values per acre-foot of water used are not affected by projected decreases in cropland and/or increases in water costs. Adjustments occurring within agriculture over the projection period take place in the acreages of those crops which produce a low net return per acre-foot of water used. As land availability decreases and/or water costs increase over the projection period, cropped acreage, total water use, and net revenue over variable production costs decline. The changes are not proportional since adjustments take place in the acreage of those crops which produce low values per acre and per acre-foot of water used. In the SRP, cropped acreage is projected to decrease 76 percent, total water use to decrease 71 percent, and net revenue over variable production costs to fall approximately 50 percent due largely to continuous transfer of land and water out of agriculture. Projected declines in cropped acreage in the RWCD are 50 percent, total water use decreases 45 percent and net revenue over variable production costs falls 21 percent due entirely to increasing cost of water. A second phase of this analysis presents a demand function for irrigation water in each district over price ranges from zero dollars per acre-foot to those at which no water would be demanded. In the SRP, positive price and quantity relationships were found to exist from a price of $248 per acre-foot at which quantity would be zero, to a quantity of 816,873 acre-feet demanded at a zero price. Price and quantity relationships in the RWCD ranged from zero quantity demanded at a price of $113.36 per acre-foot to a quantity of 130,338 acre-feet at a zero price. A final section of this study treats various possible sources, uses, and values of additional water to agriculture in each irrigation district over the projection period.

Understanding the physical properties as well as the potential for organic material in the Martian near-surface environment can give us a glimpse into the history of the site with regards to water, soil formation processes, as well as the conditions necessary for life. This work is done to support the interpretation of data from the Phoenix Mars Lander as well as other past and future landed missions. The Antarctic Dry Valleys are a hyper-arid cold polar desert that is the most Mars-like place on Earth. Soils from two different soil and climate regimes are analyzed to determine their physical properties such as mineralogy, particle size, shape, color, and specific surface area. These data are used to describe the sample locations in Antarctica and infer properties of Martian soils by comparison to Antarctic sites. I find that the particle size distribution can be used to determine the water history of the site and that the behavior of soluble species in the soil can also be used to trace the movement of water through the soil and could be instructive in understanding how soil organic material is processed by the environment. Continuing with the theme of soil organic matter, we revisit the Viking conclusions with regards to organics on Mars and look at the Phoenix data on the same subject. First, we assume that Mars receives organic material from meteoritic infall. These organics will be processed by chemical oxidants as well as UV light down to 200 nm. Chemical oxidation is predicted to produce molecules such as mellitic acid, which could preserve up to 10% of the original organic mass. Using mellitic acid and other similar organic molecules, we irradiate these molecules with Mars-like ultraviolet light, analyzing the gases that come off as irradiation takes place. We find that organic molecules can survive Mars-like UV conditions as layers of UV-resistant organics build up, shielding the remaining organic material. Additionally, the gas products of irradiation depend on the composition of the original organic molecule, implying that even irradiated molecules will carry some information about the composition of the original molecule. Finally, we take this irradiated organic/soil stimulant mixture and analyze it via pyrolysis, similar to the Viking GC/MS and TEGA instruments that are the only instruments operated on Mars capable of detecting organics. We find that the pyrolysis of mellitic acid (and other similar) molecules primarily produces inorganic fragments but that the reduced carbon fragments released depend on the composition of the original organic. However, the introduction of perchlorate, discovered on Mars by the Phoenix Lander, complicates the issue by creating the conditions for molecular oxidation. The high-oxygen content and high pyrolysis temperatures lead to organic combustion during thermal analysis, meaning that, regardless of the initial composition, most soil organics will be oxidized to CO₂ during the detection process. By assuming that organic material was oxidized to CO₂ in the Phoenix and Viking samples. We show that this assumption gives organic concentrations consistent with meteoritic accumulation rates. This finding reopens the possibility for organic molecules in the near-surface environment at the Viking and Phoenix landing sites.

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We report new ALMA observations of the CO(3-2) line emission from the 2.1 +/- 0.3*10(10)M(circle dot). molecular gas reservoir in the central galaxy of the Phoenix cluster. The cold molecular gas is fueling a vigorous starburst at a rate of 500-800M(circle dot)yr(-1) and powerful black hole activity in the forms of both intense quasar radiation and radio jets. The radio jets have inflated huge bubbles filled with relativistic plasma into the hot, X-ray atmospheres surrounding the host galaxy. The ALMA observations show that extended filaments of molecular gas, each 10-20 kpc long with a mass of several billion solar masses, are located along the peripheries of the radio bubbles. The smooth velocity gradients and narrow line widths along each filament reveal massive, ordered molecular gas flows around each bubble, which are inconsistent with gravitational free-fall. The molecular clouds have been lifted directly by the radio bubbles, or formed via thermal instabilities induced in low-entropy gas lifted in the updraft of the bubbles. These new data provide compelling evidence for close coupling between the radio bubbles and the cold gas, which is essential to explain the self-regulation of feedback. The very feedback mechanism that heats hot atmospheres and suppresses star formation may also paradoxically stimulate production of the cold gas required to sustain feedback in massive galaxies.

This dissertation provides the first demonstration of scanning synthetic aperture radar (ScanSAR) advanced interferometry processing for measuring surface deformation. ScanSAR data are synthesized from ERS-1/2 stripmap SAR images over known deformation in Phoenix, Arizona. The strategy is to construct a burst pattern similar to Envisat ScanSAR data and to create a realistic variable-burst synchronization scenario in which any image pair has at least 50% burst overlap. The Small Baseline Subsets technique is applied to the synthesized data to demonstrate ScanSAR time series analysis for a scenario generally conducive for interferometry. The same processing approach is employed with the stripmap data to validate the results. The differences in ScanSAR and stripmap velocities have a mean and standard deviation of 0.02±0.02 cm/year. 96.3% and 99.1% of the velocity differences are within ±0.1 cm/year and ±0.2 cm/year, respectively. The RMS deviations between the ScanSAR and stripmap displacement estimates are 0.40±0.30 cm. 68.5% and 94.6% of the differences are within ±0.5 cm and ±1.0 cm, respectively. The Permanent Scatterer (PS) technique also is adapted and applied to the synthesized data to demonstrate the presence of PS in ScanSAR data. The atmospheric and nonlinear motion phase derived from a PS analysis of stripmap data are removed from the ScanSAR interferograms. Even for this idealized scenario, the final PS identification yields fewer ScanSAR PS (10 PS/km²) than the stripmap PS results (312 PS/km² or 15.6 PS/km² at the ScanSAR pixel resolution). Based on the calculated likelihood of finding multiple stripmap PS within a ScanSAR pixel, it is concluded that the ScanSAR single scatterer PS model is flawed. A model is introduced that considers multiple PS within a ScanSAR pixel. The search for two PS per pixel yields 120 PS/km². The ScanSAR and stripmap PS velocity differences mean is zero and standard deviation is 0.02 cm/year. However, while the differences between the ScanSAR and stripmap PS DEM error estimates are zero-mean, they have a 7-meter standard deviation. One possible explanation for this relatively large deviation is the differencing of the wrong ScanSAR and stripmap PS as the result of a misalignment between the ScanSAR and stripmap images. / text

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Anthropologists, and increasingly archaeologists, are using the word 'ontology' with escalating frequency. In Philosophy, where it originated, several subdivisions exist within the discipline, all of which deal with grouping things that exist into categories. What can archaeologists learn by taking this concept from philosophy and applying it to archaeology? Further, how do we recognize the ontologies of others, particularly those who did not leave a written record, in the archaeological record? The way that people categorize things plays a role in how they are disposed. Patterns in depositional practices emerge as visible traces in the archaeological record that allow us to recognize other people's ontologies. This is an important concept for archaeologists interested in addressing prehistoric value, since the value of a given object cannot be assessed without knowing how people in the past categorized things. In my work with anthropomorphic Hohokam figurines from the Phoenix Basin, I use an ontological approach to explore the life histories of figurines from their manufacture, through deposition in the archaeological record, and subsequent excavation in modern times. I then compare the figurine assemblage from recent excavations at La Villa (AZ T:12:148[ASM]) to see how it fits in the identified pattern.

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Memory screening in the community promotes early detection of memory problems, as well as Alzheimer’s disease (AD) and related illnesses, and encourages appropriate intervention. The Montreal Cognitive Assessment (MoCA) is a rapid and sensitive screening tool for cognitive impairment that can be readily employed at the clinical level, but little is known about its utility as a community screening tool. Also, little is known regarding the demographics of the population that presents for a community screen. The research aims to evaluate the demographics of the participants that attended community memory screens in the greater Phoenix metropolitan area and to evaluate the prevalence of screen positives using the MoCA. It is hypothesized that cognitive impairment will be significantly prevalent in the screened population and that age and family history of dementia will correlate with the presence of cognitive impairment. The study methods involve descriptive analysis and application of statistical tests to evaluate for significant relationships between demographic variables and MoCA scores. The population (n=346) had a mean age of 72 (SD =10.7), was primarily female (70%), primarily Caucasian (68%) and 86% had greater than a high school education. A 58% prevalence of cognitive impairment was found in the population as defined by the MoCA. Increased age, male gender, and non‐Caucasian race correlated with lower MoCA scores. Lower education correlated with lower MoCA scores despite the inherent educational correction in the MoCA. Diabetes and a family history of AD were not significant factors. Although the number of true positives following methodical diagnosis is unknown, given the validity of the MoCA in discerning cognitive impairment, the screen was likely worthwhile and supports more routine use of community memory screens. Variables identified that were associated with increased cognitive impairment better describe the population at risk and can be utilized to focus future screening efforts.