An explicit universal cycle for the (n-1)-permutations of an n-set

We show how to construct an explicit Hamilton cycle in the directed Cayley graph Cay({\sigma_n, sigma_{n-1}} : \mathbb{S}_n), where \sigma_k = (1 2 >... k). The existence of such cycles was shown by Jackson (Discrete Mathematics, 149 (1996) 123-129) but the proof only shows that a certain directed graph is Eulerian, and Knuth (Volume 4 Fascicle 2, Generating All Tuples and Permutations (2005)) asks for an explicit construction. We show that a simple recursion describes our Hamilton cycle and that the cycle can be generated by an iterative algorithm that uses O(n) space. Moreover, the algorithm produces each successive edge of the cycle in constant time; such algorithms are said to be loopless

Personality as a moderator of the relationship between stress and academic deviance

Academic deviance poses a continual threat to the education system from its persistence through generations and its presence in almost every form of institutionalized education (Davis et al., 1992). The aim of the present study was to integrate both situational and individual components of stress to examine their influence on academic deviance while testing the moderating role of trait impulsiveness on the degree of academic deviance displayed. Participants were 125 (98 women, 27 men) college students at a private university in the southern region of the United States. The Academic Dishonesty Inventory (Lucas, 2005) was used to measure academic deviance, while the Barratt Impulsiveness Scale 10 (BIS-10) was utilized in order to assess impulsiveness. The Perceived Stress Scale (Cohen, Karmarck & Mermelstein, 1983) was used to gauge participants\u27 stress level. It was found that there was a significant, positive relationship between trait impulsiveness and academic deviance. However, the relationship between stress and academic deviance was not significant. Stress may play less of a role than impulsiveness in determining if an individual will engage in academic deviance. As Anderman et al. (2010) suggest, impulsiveness is indicative of the lack of selfcontrol necessary to disincline individuals to be academically deviant

Prediction of the Temporal Evolution of Solar X-Ray Flares

A solar flare is an explosive release of stored magnetic energy on the Sun. Much of this energy is converted into x-ray photons which escape into space. As a solar flare begins, the 1-8 Å x-ray photon flux at Earth’s orbit, as measured by the GOES satellite, rapidly increases. It quickly reaches a peak and slowly decays. A plot of this flux exhibits an approximate lognormal shape. A lognormal function becomes a normal, symmetric, function when the logarithm of the independent variable is taken. Once the peak flux is reached, this symmetry is used to make a prediction of the flare end time. Examining over 1300 flares, an improvement in the flare end time prediction over the current climatological method is demonstrated. Predictions of the evolution of the flux prior to reaching the peak flux are also made beginning five minutes after flare onset. An effort to predict the temporal evolution prior to the peak is made using a fourth order least squares fit to the rise-phase flux alone and the rise-phase flux plus an estimate of the decay flux. Using both methods, accurate predictions of the x-ray flux evolution are made when the rise phase averages 65% complete

Lean NOx Trap Catalysis for Lean Burn Natural Gas Engines

As the nation’s demand for energy grows along with concern for the environment, there is a pressing need for cleaner, more efficient forms of energy. The internal combustion engine is well established as one of the most reliable forms of power production. They are commercially available in power ranges from 0.5 kW to 6.5 MW, which make them suitable for a wide range of distributed power applications from small scale residential to large scale industrial. In addition, alternative fuels with domestic abundance, such as natural gas, can play a key role in weaning our nations dependence on foreign oil. Lean burn natural gas engines can achieve high efficiencies and can be conveniently placed anywhere natural gas supplies are available. However, the aftertreatment of NOx emissions presents a challenge in lean exhaust conditions. Unlike carbon monoxide and hydrocarbons, which can be catalytically reduced in lean exhaust, NOx emissions require a net reducing atmosphere for catalytic reduction. Unless this challenge of NOx reduction can be met, emissions regulations may restrict the implementation of highly efficient lean burn natural gas engines for stationary power applications. While the typical three-way catalyst is ineffective for NOx reduction under lean exhaust conditions, several emerging catalyst technologies have demonstrated potential. The three leading contenders for lean burn engine de-NOx are the Lean NOx Catalyst (LNC), Selective Catalytic Reduction (SCR) and the Lean NOx Trap (LNT). Similar to the principles of SCR, an LNT catalyst has the ability to store NOx under lean engine operation. Then, an intermittent rich condition is created causing the stored NOx to be released and subsequently reduced. However, unlike SCR, which uses urea injection to create the reducing atmosphere, the LNT can use the same fuel supplied to the engine as the reductant. LNT technology has demonstrated high reduction efficiencies in diesel applications where diesel fuel is the reducing agent. The premise of this research is to explore the application of Lean NOx Trap technology to a lean burn natural gas engine where natural gas is the reducing agent. Natural gas is primarily composed of methane, a highly stable hydrocarbon. The two primary challenges addressed by this research are the performance of the LNT in the temperature ranges experienced from lean natural gas combustion and the utilization of the highly stable methane as the reducing agent. The project used an 8.3 liter lean burn natural gas engine on a dynamometer to generate the lean exhaust conditions. The catalysts were packaged in a dual path aftertreatment system, and a set of valves were used to control the flow of exhaust to either leg during adsorption and regeneration. The rich conditions for regeneration were created by injecting natural gas directly into the exhaust stream. An oxidation and reforming catalyst were placed upstream of the LNT to enhance the utilization of the methane. The duration of time for catalyst adsorption (sorption period) and the amount of fuel for regeneration (injection rate) were the two primary variables used in developing the regeneration strategy. The goal of this study was to optimize the regeneration strategy for 5 modes of engine operation (10%, 25%, 50%, 75% and 100% load) at 1800 rpm. In optimizing this strategy, NOx reduction efficiencies greater than 90% were demonstrated for 25% and 50% engine load. Testing at 10%, 75% and 100% load revealed the temperature dependence of both the LNT and oxidation catalyst. Low temperatures at 10% load hindered the oxidation catalyst’s ability to break down the methane, while the storage capacity of the LNT falls off at the higher temperatures of 75% and 100% load. This created a narrow temperature window in which the performance could be optimized

CITIZENS, FOREIGNERS, OR GERMANS? THE STATE AND PERSONS OF IMMIGRANT BACKGROUND IN THE MAKING OF MEMBERSHIP IN GERMANY SINCE 1990

This dissertation examines citizenship and nationness in contemporary Germany. It argues that citizenship and nationness represent two forms of membership which are constituted at the level of state and at the level of prospective citizens. At the level of the state, it considers changes in German citizenship policies in 1990, 1992, and 2000. At the level of prospective citizens, it examines forty-seven persons of immigrant background and their understandings of German citizenship and their own nationness. Though not the same, citizenship and nationness may be related in various ways. Previous scholarship shows that nationness has been a key category and criterion for who may become a citizen at the level of state, as expressed in citizenship policies. Similarly, the self-understandings of individuals as members of the nation may inform their decision to become citizens. Equally, their citizenship status may inform their sense of their own nationness. Finally, understandings of citizenship and nationness which are institutionalized in the state may inform the understandings of persons of immigrant background. Beginning in 1990, citizenship policies became increasingly more liberalized and accessible to persons of immigrant background without German descent. This dissertation shows that these changes after 1990 are explained by understandings of nationness, as expressed in narratives of political parties about immigrants and foreigners, Germany and the nation, and citizenship as an institution. Contrary to scholarship emphasizing nationally-specific traditions of citizenship, as well as shifts towards liberalizing access to citizenship, this dissertation shows that understandings of nationness differ mainly by political parties. The self-understandings of persons of immigrant background reflect some, but not all, of the changes at the level of the state. In particular, most persons of immigrant background see themselves as German and as belonging in everyday life in Germany. However, their citizenship status is largely independent of their sense of national belonging. This suggests that national belonging and citizenship are largely disconnected for ordinary people. In addition, the disconnect between nationness and citizenship is more pronounced for persons who are citizens, indicating that they view their membership as citizens should be met with a sense of national membership

Evaluating the Potential of a Geospatial/Geostatistical Methodology for Locating Rain-Derived Infiltration and Inflow into Wastewater Treatment Systems in the Minneapolis/St. Paul Metropolitan Area, Minnesota, USA

A significant issue facing municipal wastewater treatment infrastructure (WWTI) is how to manage infiltration and inflow (I/I). I/I of rain and ground water permeate into WWTI after precipitation events, periods of groundwater table rise, and percolation from surrounding surface waters. This can create discharges above the infrastructure\u27s flow capacity, increase costs for processing the wastewater and add undesired stress to aging wastewater networks. In an attempt to assess this problem cost and time inefficient approaches have commonly been applied. This study utilizes a new and more radical methodology to try and make WWTI management more efficient. This study applies ArcGIS and Geostatistical Analysis to seven counties within the Metropolitan Council Environmental Services (MCES) network in the Minneapolis/St. Paul metro area. Data is collected from rain gauges and flow meters an average ten-year flow record is created from this data. The data is then analyzed in ArcGIS through Kriging to interpolate and predict where significant rates of I/I, due to high magnitude precipitation events, are located throughout the study area. I/I rates for high magnitude precipitation events are estimated through the comparison of the max flow rate data and the ten-year average flow rate. A percentage of increase flow is then calculated. Results reveal spatial patterns indicating variable I/I susceptibility across the MCES WWTI. By collaborating with MCES it is possible to determine how accurately this methodology can locate areas of high-risk I/I potential within the existing WWTI

Synthesis and Characterization of Monosaccharide-derived Low Molecular Weight Gelators

Low molecular weight gelators (LMWGs) are interesting materials whose applications are as diverse and wide ranging as their molecular structures. These materials self-assemble through the formation of non-covelent intermolecular forces and interactions to form supramolecular assemblies that trap solvent within their matrices. Because of the non-covalent nature of the forces of self-assembly, the gelation process is typically thermally reversible. In addition, low molecular weight gelators can also be modified to respond to various stimuli, such as change in pH, presence of enzymes or metal cations, or exposure to light. The design of low molecular weight gelators is often difficult, and most new classes of low molecular weight gelators are discovered by serendipity. As such, it is often useful to use structural templates in the design of LMWGs. Biomolecules, such as steroids, amino acids and peptides, and carbohydrates make excellent templates due to their inherent propensity to self assemble. A review of the current literature regarding the use of biomolecules as templates for the design and synthesis of LMWGs will be presented in chapter 1. Our research group has been active in the research of carbohydrate-based LMWGs for several years, and these results are also briefly reviewed in the related chapters. The synthesis and characterization of ester derivatives of D-galactose, D-glucose, and amide derivatives of D-glucosamine will be discussed in chapters 2-4, along with their evaluation for gelation in aqueous and organic solvents, such as hexane, ethanol, water, and aqueous DMSO or ethanol mixtures

Synthesis and Characterization of Monosaccharide-derived Low Molecular Weight Gelators

Low molecular weight gelators (LMWGs) are interesting materials whose applications are as diverse and wide ranging as their molecular structures. These materials self-assemble through the formation of non-covelent intermolecular forces and interactions to form supramolecular assemblies that trap solvent within their matrices. Because of the non-covalent nature of the forces of self-assembly, the gelation process is typically thermally reversible. In addition, low molecular weight gelators can also be modified to respond to various stimuli, such as change in pH, presence of enzymes or metal cations, or exposure to light. The design of low molecular weight gelators is often difficult, and most new classes of low molecular weight gelators are discovered by serendipity. As such, it is often useful to use structural templates in the design of LMWGs. Biomolecules, such as steroids, amino acids and peptides, and carbohydrates make excellent templates due to their inherent propensity to self assemble. A review of the current literature regarding the use of biomolecules as templates for the design and synthesis of LMWGs will be presented in chapter 1. Our research group has been active in the research of carbohydrate-based LMWGs for several years, and these results are also briefly reviewed in the related chapters. The synthesis and characterization of ester derivatives of D-galactose, D-glucose, and amide derivatives of D-glucosamine will be discussed in chapters 2-4, along with their evaluation for gelation in aqueous and organic solvents, such as hexane, ethanol, water, and aqueous DMSO or ethanol mixtures

The Noisy Silent Witness : The Misperception and Misuse of Criminal Video Evidence

This Note examines recent developments in the research of situational video evidence biases. Part I examines the current and growing body of psychological research into the various situational biases that can affect the reliability of video evidence and the gaps in this research that require further attention from researchers and legal academics. Because these biases do not “operate in a vacuum,” Part I also examines some of the recent and exciting research into the interaction between situational and dispositional biases. Part II examines the development of camera and video processing technology and its limitations as a means of mitigating such biases. Part III explains how such research could be used to develop heuristics to better assess the admissibility or presentation of video evidence and the need for greater judicial scrutiny of video evidence. This Note concludes by highlighting the potential research about the situational factors affecting the perception that video evidence has for producing insights useful for practitioners conducting criminal trials and municipalities and police forces adopting video technology, and closes with suggestions for further research

Development of a SimpleProbe real-Time PCR Assay for rapid detection and identification of the US novel urethrotropic clade of Neisseria meningitidis ST-11 (US_NmUC)

Urethritis, or inflammation of the urethra, is one of the most common reasons men seek clinical care. Sexually transmitted pathogens including Neisseria gonorrhoeae are responsible for over half of the symptomatic urethritis cases in U.S. men. Recently, clinics in Indianapolis, Columbus, Atlanta, and other U.S. cities began to note increasing numbers of men presenting with urethritis and Gram-negative intracellular diplococci in their urethral smears who test negative for N. gonorrhoeae. Many of these discordant cases, which have periodically reached highs of more than 25% of presumed gonococcal cases in some sexually transmitted infection clinics in the U.S. Midwest, are infected with strains in a novel urethrotropic clade of Neisseria meningitidis ST-11 (US_NmUC). However, no cultivation-independent tests are available for the US_NmUC strains, and prior studies relied on microbial culture and genome sequencing to identify them. Here, we describe a PCR test that can identify the US_NmUC strains and distinguish them from commensal and invasive N. meningitidis strains as well as N. gonorrhoeae. Our SimpleProbe®-based real-time PCR assay targets a conserved nucleotide substitution in a horizontally acquired region of US_NmUC strain genomes. We applied the assay to 241 urine specimens whose microbial compositions had previously been determined by deep shotgun metagenomic sequencing. The assay detected the single US_NmUC positive case in this cohort, with no false positives. Overall, our simple and readily adaptable assay could facilitate investigation of the pathogenesis and epidemiology of the US_NmUC clade