Limitations on Canada Goose Production at Fish Springs National Wildlife Refuge, Utah

Canada geese (Branta canadensis) recently have become management problems in some areas due to overpopulation At Fish Springs National Wildlife Refuge (NWR). managers are concerned with the opposite situation Despite attempts to boost production, only 18 to 34 goslings of the western Canada goose (B. c. moffitti) were produced per year, from 1989 to 1993. I studied the breeding population from March to July in 1996 and 1997. Results suggest that production is limited in 3 ways: low gosling survival. low nesting success for ground nests, and low number of breeding pairs Gosling survival to fledging was 25% in 1996 and 52% in 1997. I examined the potential causes of low gosling survival, especially the effects of saline drinking water. Specific conductivities in the spring-fed marshes of the desert refuge range from 3.0 to 25.0+ μS/cm. conducted an experiment on captive wild-strain goslings. Three groups received different levels of saline \\ater as measured by specific conductivity: control (0 63 μS/cm), intermediate 12.0 ~1Slcm). and high (18.0 ~1Slcm) I found mortality only at the high level Effects on growth were growth were evident at both the intermediate and high levels, although statistically significant only at the high level. To examine the effects of saline drinking water on survival of free-ranging wild goslings, I collared and radio marked breeding adults, then monitored brood location and gosling numbers. I found that mortality was independent of specific conductivity levels on the brood-rearing impoundments. Observations suggest that the primary causes of low gosling survival involve predation and human disturbance. l compared my results lo the results of other studies. Accuracy of results appears to be related to the estimation technique used. Radio tracking of broods has the potential to be very accurate. Al Fish Springs NWR. l monitored nesting pairs. nests, and broods throughout the breeding season. Ground nests had lower nesting success in both years (56%: 41 %) than artificial nesting platforms (90%, 83%). The number of nesting pairs was 26 and 34 in 1996 and 1997, respectively. Based on these results, l made several management recommendations, including installing more artificial nesting platforms. and minimizing human disturbance

Doctor of Philosophy

dissertationChapter 1 describes detailed mechanistic studies that were conducted on three discreet Nickel-catalyzed [2+2+2] cycloaddition reactions of diyne and nitriles to afford pyridines. Reaction profiles demonstrated in all cases a heterooxidative coupling mechanism, contrary to other common cycloaddition catalysts. Through kinetic analysis of the Ni(IPr)2-catalyzed cycloaddition, observed regioisomerism of the products, and stoichiometric reactions, Ni(IPr)2 appears to have catalyzed the cycloaddition by proceeding via a heterooxidative coupling mechanism. Strong coordination and considerable steric bulk of the carbene ligands facilitates selective initial binding of the nitrile, inducing an η1-(IPr)2Ni(NCR) catalytic resting state. Chapter 2 then reports on the reaction of Ni(COD)2, IPr, and nitriles to afford dimeric [Ni(IPr)RCN]2 in high yields. These dimers are catalytically competent in the formation of pyridines from the cycloaddition of diynes and nitriles, wherein the dimeric state was found to be largely preserved throughout the reaction. Observations suggest a mechanism whereby the catalyst is activated by partial dimer-opening followed by binding of exogenous nitrile and subsequent oxidative heterocoupling, leading to pyridine products. Comparative investigations into the mechanism of the cycloaddition of diynes and nitriles catalyzed by a complementary Ni(COD)2/Xantphos catalyst are discussed in Chapter 3. Kinetic analysis of two Ni/Xantphos catalysts reveal zeroeth-order in all substrates but catalyst, suggesting a (Xantphos)Ni(diyne) resting state with rate-limiting partial phosphine dissociation. Chapter 4 then describes the discovery of cyanamides as highly active substrates for cycloaddition with alkynes and diynes. The observed reactivity was further investigated by utilizing a number of cyanamides with diverse functional groups. A variety of bicyclic N,N-disubstituted-2-aminopyridines were prepared from both terminal- and internal-diynes with cyanamides in a selective manner. Two examples of three-component cycloadditions were conducted and found to be selective and high yielding. Chapter 5 expands on Chapter 4 illustrating the cross-coupling of alkyl cyanamides with a number of aryl, heteroaryl, and vinyl halide and pseudohalide coupling partners. The synthesis was possible via a modification of reported Pdcatalyzed amidation methods. The reactions proceed selectively under mild conditions with reasonable reaction times in moderate to excellent yields

Does Your Dog Really Want a Trip to the Beauty Parlor?

Pet spas (especially for dogs) are a $6 billion business in America. Why humans subject their pets to curling, coloring and other treatments is discussed and analyzed

Mass Spectrometry Imaging Characterization of Ethiodized Oil, a Radiopaque Hydrophobic Multipurpose Liquid Used in Cancer Therapy

https://openworks.mdanderson.org/sumexp21/1226/thumbnail.jp

Prevalence and Predictors of Low Serum 25-Hydroxyvitamin D among Female African-American Breast Cancer Survivors

Background: African-American breast cancer survivors commonly demonstrate low serum 25-hydroxyvitamin D (25(OH)D). Decreased cutaneous conversion, high levels of adiposity, and even breast cancer treatment may influence vitamin D status. Previous investigations have analyzed African-American women in aggregate with other breast cancer survivors and have not comprehensively addressed these influential factors

Gender Differences in the Response to Decision Power and Responsibility : Framing Effects in a Dictator Game

This paper studies the effects of two different frames on decisions in a dictator game. Before making their allocation decision, dictators read a short text. Depending on the treatment, the text either emphasizes their decision power and freedom of choice or it stresses their responsibility for the receiver’s payoff. Including a control treatment without such a text, three treatments are conducted with a total of 207 dictators. Our results show a different reaction to these texts depending on the dictator’s gender. We find that only men react positively to a text that stresses their responsibility for the receiver, while only women seem to react positively to a text that emphasizes their decision power and freedom of choice