BIOGEOGRAPHY AND PATTERN VARIATION OF KINGSNAKES, LAMPROPELTIS GETULA, IN THE APALACHICOLA REGION OF FLORIDA

Morphology of kingsnakes, Lampropeltis getula, is described and analyzed in the Apalachicola region of the Florida panhandle. Populations inhabiting the eastern Apalachicola Lowlands, a distinct biotic province, are different from the surrounding populations in having fewer and wider light body crossbands, distinct ontogenetic interband lightening, unique ventral patterns, and the presence of non-banded (striped and patternless) individuals. We conclude that the name L. g. goini as well as the hypothesis that Apalachicola L. getula are relict populations of intergrades between L. g. getula and L. g. floridana are invalid. We believe the polymorphic eastern Apalachicola Lowlands populations are most closely related to L. g. getula, and evolved in isolation on a barrier island or the coastal strand of a peninsula during one of the many higher stands of sea in the Pleistocene

VALUE OF IRRIGATION WATER IN THE MIDDLE ATLANTIC STATES: AN ECONOMETRIC APPROACH

Estimation of the economic value of irrigation water is complicated by a lack of data on the price or marginal cost of water. Through econometric estimation of an aggregate total value product function, this paper obtains marginal irrigation water value estimates for the Middle Atlantic region. Additionally, the impact of temperature and soil conditions on aggregate production within the region is estimated. Ridge regression and covariance analysis are employed to deal with problems of multicollinearity and simultaneous equation bias, respectively. Estimates indicate a substantial and growing return to irrigation within the region.Resource /Energy Economics and Policy,

Emission from Very Small Grains and PAH Molecules in Monte Carlo Radiation Transfer Codes: Application to the Edge-On Disk of Gomez's Hamburger

We have modeled optical to far infrared images, photometry, and spectroscopy of the object known as Gomez's Hamburger. We reproduce the images and spectrum with an edge-on disk of mass 0.3M_sun and radius 1600AU, surrounding an A0 III star at a distance of 280pc. Our mass estimate is in excellent agreement with recent CO observations. However, our distance determination is more than an order of magnitude smaller than previous analyses which inaccurately interpreted the optical spectrum. To accurately model the infrared spectrum we have extended our Monte Carlo radiation transfer codes to include emission from polycyclic aromatic hydrocarbon (PAH) molecules and very small grains (VSG). We do this using pre-computed PAH/VSG emissivity files for a wide range of values of the mean intensity of the exciting radiation field. When Monte Carlo energy packets are absorbed by PAHs/VSGs we reprocess them to other wavelengths by sampling from the emissivity files, thus simulating the absorption and re-emission process without reproducing lengthy computations of statistical equilibrium, excitation and de-excitation in the complex many level molecules. Using emissivity lookup tables in our Monte Carlo codes gives the flexibility to use the latest grain physics calculations of PAH/VSG emissivity and opacity that are being continually updated in the light of higher resolution infrared spectra. We find our approach gives a good representation of the observed PAH spectrum from the disk of Gomez's Hamburger. Our models also indicate the PAHs/VSGs in the disk have a larger scaleheight than larger radiative equilibrium grains, providing evidence for dust coagulation and settling to the midplane.Comment: ApJ accepte

Problems in elastostatics involving unbounded bodies

Issued as Annual report and Final report, Project no. G-37-61

A Study of the EUR/USD Exchange Rate and EUR Call Options

International business has grown rapidly in recent years as companies seek to take advantage of expanding market and supply chain opportunities. As companies enter into contracts to take advantage of engineering, production, and cost reduction capabilities of the global supply chain, they may be creating a foreign currency exchange rate risk. The purpose of this quantitative study was to endeavor to develop a multiple linear regression EUR/USD forecasting methodology for companies to use when determining when to use currency call options for managing currency risk in accounts payable. The study examined the 60-day EUR/USD exchange rate fluctuation with the conclusion that the variability of the EUR/USD over 60-days does pose financial risk to a company. Multiple linear regression models were created using historical exchange rate data, interest rate data, and Brent crude oil price data. The multiple linear regression models using historical data were not statistically significant in predicting the directional movement of the EUR/USD. This finding aligns with the weak form of the efficient market hypothesis. The study also found that using currency call options to hedge this 60-day exchange rate risk resulted in an overall financial loss as compared to no hedging. The findings suggest that historical data alone cannot be used to predict future EUR/USD directional movements and that purchasing call options to hedge the risk results in a net financial loss. The study did not address the financial benefits of the use of hedging to smooth financial results

Phylogeography of the desert horned lizard (Phrynosoma platyrhinos) and the short-horned lizard (Phrynosoma douglassi): Patterns of divergence and diversity

Historical environmental change is thought to have played an important role in the diversification of the biota of western North America. Many patterns of diversification have been associated with glacial-interglacial cycles of the latest Pleistocene. Recent evidence on diversification patterns in small mammals suggests a response to older environmental change, especially the uplift of the western North American cordillera; To evaluate the relative influence of old and recent historical environmental change on lineage diversification, mitochondrial DNA molecular phylogeographies of Phrynosoma douglassi (the short-horned lizard) and Phrynosoma platyrhinos (the desert horned lizard) were analyzed. Both species are widespread and have relatively old histories in western North America; P. douglassi and P. platyrhinos demonstrated multiple scales of lineage diversification representating responses to relatively old and recent historical environmental change. Deep levels of divergence in P. douglassi were structured geographically among Kuchler Physiographic regions and were temporally concordant with the late Tertiary uplift of the western North American cordillera. Significant phylogenetic gaps between regions suggest long-term barriers to gene flow among regions. P. platyrhinos demonstrated a deep divergence between the southern Sonoran Desert and the remainder of the species\u27 range. With the assumption of 2% divergence per million years, this divergence roughly corresponds to the Bouse Embayment, a large lake incursion that divided areas east and west of the Colorado River during the Pliocene. Assuming a roughly consistent rate of molecular evolution, both species exhibit divergence depths within regions indicative of response to Pleistocene glacial-interglacial cycles; The depth of lineage diversity in P. douglassi and P. platyrhinos was concordant with a model of habitat change during the last glacial maximum. Regions that maintained large patches of suitable habitat during the last glacial maximum had deep levels of divergence whereas regions that lost large areas of suitable habitat had shallow levels of within-region divergence; The phylogeographic patterns of P. douglassi and P. platyrhinos, and results of simulated habitat change, do not support a model of mass habitat shift to the south in response to glaciation. Rather, results of this study suggest that suitable habitats and populations persisted in many areas within the current ranges of both species ranges during the last glacial maximum, although the distribution of P. platyrhinos was more limited

Stress, Gender and Policing: The Impact of Perceived Gender Discrimination on Symptoms of Stress

Police work is inherently stressful. However, the traditionally male-dominated field of policing may create increased obstacles and stressors for female oficers. Therefore, the purpose of this study is to examine gender differences in the perception of gender discrimination and in levels of stress. The results indicate that male and female officers have conflicting attitudes about the amount and nature of gender discrimination within police work. The findings further suggest that female officers experience higher levels of stress. In addition, the results indicate a weak relationship between perceptions ofgender-related jokes and stress levels for females. Interestingly, male officers who report that females are held to a higher standard experience lower levels of stress. Nevertheless, the most important stressor for both males and females is the perception ofjob-related problems