Synthetic Mudscapes: Human Interventions in Deltaic Land Building

In order to defend infrastructure, economy, and settlement in Southeast Louisiana, we must construct new land to mitigate increasing risk. Links between urban environments and economic drivers have constrained the dynamic delta landscape for generations, now threatening to undermine the ecological fitness of the entire region. Static methods of measuring, controlling, and valuing land fail in an environment that is constantly in flux; change and indeterminacy are denied by traditional inhabitation. Multiple land building practices reintroduce deltaic fluctuation and strategic deposition of fertile material to form the foundations of a multi-layered defence strategy. Manufactured marshlands reduce exposure to storm surge further inland. Virtual monitoring and communication networks inform design decisions and land use becomes determined by its ecological health. Mudscapes at the threshold of land and water place new value on former wastelands. The social, economic, and ecological evolution of the region are defended by an expanded web of growing land

Photochemistry in the arctic free troposphere: Ozone budget and its dependence on nitrogen oxides and the production rate of free radicals

Abstract. Local ozone production and loss rates for the arctic free troposphere (58–85 ◦ N, 1–6 km, February–May) during the Tropospheric Ozone Production about the Spring Equinox (TOPSE) campaign were calculated using a constrained photochemical box model. Estimates were made to assess the importance of local photochemical ozone production relative to transport in accounting for the springtime maximum in arctic free tropospheric ozone. Ozone production and loss rates from our diel steady-state box model constrained by median observations were first compared to two point box models, one run to instantaneous steady-state and the other run to diel steady-state. A consistent picture of local ozone photochemistry was derived by all three box models suggesting that differences between the approaches were not critical. Our model-derived ozone production rates increased by a factor of 28 in the 1–3 km layer and a factor of 7 in the 3–6 km layer between February and May. The arctic ozone budget required net import of ozone into the arctic free troposphere throughout the campaign; however, the transport term exceeded the photochemical production only in the lower free troposphere (1–3 km) between February and March. Gross ozone production rates were calculated to increase linearly with NOx mixing ratios up to ∼300 pptv in February and for NOx mixing ratio

Materials Characterization Using Acoustic Nonlinearity Parameters and Harmonic Generation: Effects of Crystalline and Amorphous Structures

The importance of nonlinearity in the description of material behavior is gaining widespread attention. Nonlinearity plays a major, if not dominating, role in a number of material properties. For example, properties that are important in engineering design such as thermal expansion or the pressure dependence of optical refraction are inherently nonlinear [1]. New assembley techniques such as the use of ultrasonic gauges to determine the loading of critical fasteners depend upon nonlinear properties of the fasteners [2]. Areas of considerable fundamental interest in nonlinearity include lattice dynamics [3], radiation stress in solids [4,5], and nonlinear optics [6

Supercritical fluid explosion process to aid fractionation of lipids from biomass

Disclosed are processes for development and recovery of lipids from biomass. A plant or microorganism-based biomass can be developed to encourage a desired lipid profile. Following development, ecologically friendly normally gaseous fluids such as carbon dioxide can be pressurized to a supercritical state followed by rapid expansion. The fluid is first contacted with a biomass source including oil-containing microorganisms and/or agricultural products. For instance, fungi or algae can be bioconverted from another biomass sources such as canola seed or corn syrup and then contacted with the high pressure fluid. During a contact period, the fluid can diffuse into the biomass, and in particular through the cell walls of the biomass. The fluid undergoes rapid release of pressure and opens the cell structure for improved release of oil. The fluid can optionally be utilized for extraction following the explosion process. For instance, the fluid can be re-pressurized in the same vessel for extraction processes

Measurements of ice nucleation by mineral dusts in the contact mode

Formation of ice in Earth\u27s atmosphere at temperatures above approximately −20 °C is one of the outstanding problems in cloud physics. Contact nucleation has been suggested as a possible mechanism for freezing at relatively high temperatures; some laboratory experiments have shown contact freezing activity at temperatures as high as −4 °C. We have investigated Arizona Test Dust and kaolinite as contact nuclei as a function of size and temperature and find that the fraction of submicron particles that are active as contact ice nuclei is less than 10−3 for −18 °C and greater. We also find that the different dusts are quite distinct in their effectiveness as contact nuclei; Arizona Test Dust catalyzed freezing in the contact mode at all mobility diameters we tested at −18 °C whereas kaolinite triggered freezing only for mobility diameters of 1000 and 500 nm at that temperature

Perceptions of Well-Being Among Rural Nebraskans

Nebraska’s economy has been relatively stable during the past year. However, some rural areas continue to be economically challenged. How do rural Nebraskans perceive their quality of life? Do their perceptions differ by community size, the region in which they live, or their occupation? This report details 2,482 responses to the 2006 Nebraska Rural Poll, the eleventh annual effort to understand rural Nebraskans’ perceptions. Respondents were asked a series of questions regarding their individual well-being. Trends for these questions are examined by comparing data from the ten previous polls to this year’s results. In addition, comparisons are made among different respondent subgroups, that is, comparisons by age, occupation, region, etc. Based on these analyses, some key findings emerged: • More rural Nebraskans report being satisfied with their job opportunities this year as compared to previous years. After reaching a low of 34 percent in 2004, the proportion satisfied with their job opportunities increased to 42 percent this year (the highest proportion in all 11 years). (page 5) • Persons with the highest household incomes are more likely than persons with lower incomes to feel they are better off compared to five years ago, are better off compared to their parents when they were their age, and will be better off ten years from now. For example, 52 percent of respondents with household incomes of $60,000 or more think they will be better off ten years from now. However, only 22 percent of respondents with household incomes under$20,000 believe they will be better off ten years from now. (page 6) • More rural Nebraskans believe people are powerless to control their own lives this year as compared to past years. The proportion that either strongly agree or agree with the statement that people are powerless to control their own lives each year has averaged about 34 percent. The proportion agreeing with the statement increased slightly, to 38 percent this year, which matches the highest proportion in the 11 years of the Poll (1997 and 1999 were the other two years). (page 4) • Persons with lower education levels are more likely than persons with more education to believe that people are powerless to control their own lives. Forty-six percent of persons with a high school diploma or less education agree that people are powerless to control their own lives. However, only 25 percent of persons with a four-year college degree share this opinion. (page 9) • Rural Nebraskans continue to be generally positive about their current situation. Except in 2003, each year the proportion of rural Nebraskans that say they are better off than they were five years ago has been greater than the proportion saying they are worse off than they were five years ago. Approximately 36 percent each year have reported that they were better off than they were five years ago. This year, 35 percent believe they are better off then they were five years ago and 21 percent think they are worse off. (page 2) • Similarly, rural Nebraskans continue to be generally positive about their future. The proportion that say they will be better off ten years from now has always been greater than the proportion saying they will be worse off ten years from now (although the two were virtually identical in 1996). The proportion stating they will be better off ten years from now has generally remained about 36 percent. This year, the proportion was 34 percent. Twenty-one percent believe they will be worse off ten years from now. (page 3) • Following trends in previous years, rural Nebraskans are most satisfied with their marriage, family, friends, religion/spirituality and the outdoors. They continue to be less satisfied with job opportunities, current income level and financial security during retirement. (page 5

Coupled evolution of BrOx-ClOx-HOx-NOx chemistry during bromine-catalyzed ozone depletion events in the arctic boundary layer

Extensive chemical characterization of ozone (O3) depletion events in the Arctic boundary layer during the TOPSE aircraft mission in March-May 2000 enables analysis of the coupled chemical evolution of bromine (BrOx), chlorine (ClOx), hydrogen oxide (HOx) and nitrogen oxide (NOx) radicals during these events. We project the TOPSE observations onto an O3 chemical coordinate to construct a chronology of radical chemistry during O3 depletion events, and we compare this chronology to results from a photochemical model simulation. Comparison of observed trends in ethyne (oxidized by Br) and ethane (oxidized by Cl) indicates that ClOx chemistry is only active during the early stage Of O3 depletion (O3 > 10 ppbv). We attribute this result to the suppression of BrCl regeneration as O3 decreases. Formaldehyde and peroxy radical concentrations decline by factors of 4 and 2 respectively during O3 depletion and we explain both trends on the basis of the reaction of CH2O with Br. Observed NOx concentrations decline abruptly in the early stages Of O3 depletion and recover as O3 drops below 10 ppbv. We attribute the initial decline to BrNO3 hydrolysis in aerosol, and the subsequent recovery to suppression of BrNO3 formation as O3 drops. Under halogen-free conditions we find that HNO4 heterogeneous chemistry could provide a major NOx sink not included in standard models. Halogen radical chemistry in the model can produce under realistic conditions an oscillatory system with a period of 3 days, which we believe is the fastest oscillation ever reported for a chemical system in the atmosphere

Adapting to the Current Economic Climate in Non-Metropolitan Nebraska

The national economy has faltered during the past year. While Nebraska’s economy has also faltered, it has not seen the level of job losses and mortgage foreclosures that have occurred in other parts of the country. Given these conditions, what do rural Nebraskans think about the current economic climate? How has their household been impacted during the past year? What changes have they made because of concerns about the economy? How concerned are they about financial matters? This paper provides a detailed analysis of these questions. This report details 2,852 responses to the 2009 Nebraska Rural Poll, the fourteenth annual effort to understand rural Nebraskans’ perceptions. Respondents were asked a series of questions about the current economic climate. For all questions, comparisons are made among different respondent subgroups, that is, comparisons by age, occupation, region, etc