Effects of Ambient and Laser Light on Water Evaporation from the Surface of Polyurethane Swabs Doped with Surfactant

Polyurethane swabs are a common instrument for environmental sampling in the food, medical, and forensic fields due to their high recovery of organisms like viruses, spores, and bacteria. For sampling microbes in food and medical facilities, storage of the collected samples occurs under the absence of light to promote growth for more accurate testing. In the forensic fields, microbial growth results in sample contamination so the inhibition of this growth requires the drying of the swabs. This work studies the evaporation rates of water from polyurethane swabs under zero watt incident light, 30 W fluorescent bulb, 50 mW 532 nm laser, and surfactant dopant conditions to determine the effects of each condition on the swab recovery. Overall, the zero-watt incident light condition resulted in the lowest evaporation rates without surfactant dopant, but with surfactant dopant, the zero-watt incident light had evaporation rates higher than that of the 30 W fluorescent light bulb. Under 50 mW laser irradiation, the evaporation rate of water from the polyurethane swabs was consistently higher under all conditions. A dynamic period was observed when irradiating the swabs with the laser, which showed that from 0-60 s, the laser resulted in lower evaporation rates but after 60 s, the laser irradiation resulted in higher evaporation rates than the other conditions. These results showed that for food and medical fields needing the swabs to have reduced water evaporation; use of swabs doped with surfactant would allow for increased intake as well as reduced evaporation, while forensic science fields could use a 532 nm laser to dry the swabs to minimize microbial growth

Intimate encounters with violence: media and trauma in the work of Phyllis Webb and Daphne Marlatt

This dissertation looks at the work of Phyllis Webb and Daphne Marlatt, two West Coast Canadian poets who explored questions of media technologies and trauma violence in their work during the latter half of the twentieth century. This thesis takes up contemporary phenomenological and feminist analyses of the connections between media technologies and trauma, especially war violence, in relation to both the creative and practical careers of these two writers. Research into the histories of media technologies such as the letter, radio, photography, and television shows how these technologies have shaped our experience of violence both globally and locally, from nineteenth-century colonial garrisons in Canada to the internment of Japanese Canadians during the Second World War to the 1991 Gulf War. Ultimately, this dissertation suggests that these two poets offer new phenomenological interpretations of the ways in which media technologies shape our perception of historical, hidden traumas

Corporate bond prices and idiosyncratic risk: evidence from Australia

In this paper we investigate the bond price effect upon the information arrival of firm-specific idiosyncratic risk. We consider idiosyncratic dispersion and idiosyncratic volatility that capture, respectively, the direction of information and the magnitude of idiosyncratic risk. We find that idiosyncratic volatility does not affect bond prices, while the direction of idiosyncratic risk which reflects the favorable or unfavorable information exhibits impacts on bond prices. Idiosyncratic dispersion in the stock return of a firm in the preceding week, in general, is positively associated with bond price changes in the current week. This effect is most pronounced for firms exhibiting characteristics associated with lower default risk

The Temporal Dynamics Model of Emotional Memory Processing: A Synthesis on the Neurobiological Basis of Stress-Induced Amnesia, Flashbulb and Traumatic Memories, and the Yerkes-Dodson Law

We have reviewed research on the effects of stress on LTP in the hippocampus, amygdala and prefrontal cortex (PFC) and present new findings which provide insight into how the attention and memory-related functions of these structures are influenced by strong emotionality. We have incorporated the stress-LTP findings into our “temporal dynamics” model, which provides a framework for understanding the neurobiological basis of flashbulb and traumatic memories, as well as stress-induced amnesia. An important feature of the model is the idea that endogenous mechanisms of plasticity in the hippocampus and amygdala are rapidly activated for a relatively short period of time by a strong emotional learning experience. Following this activational period, both structures undergo a state in which the induction of new plasticity is suppressed, which facilitates the memory consolidation process. We further propose that with the onset of strong emotionality, the hippocampus rapidly shifts from a “configural/cognitive map” mode to a “flashbulb memory” mode, which underlies the long-lasting, but fragmented, nature of traumatic memories. Finally, we have speculated on the significance of stress-LTP interactions in the context of the Yerkes-Dodson Law, a well-cited, but misunderstood, century-old principle which states that the relationship between arousal and behavioral performance can be linear or curvilinear, depending on the difficulty of the task

PERMISSIVE INFLUENCE OF STRESS IN THE EXPRESSION OF A U-SHAPED RELATIONSHIP BETWEEN SERUM CORTICOSTERONE LEVELS AND SPATIAL MEMORY ERRORS IN RATS

The relationship between glucocorticoids (GCs) and memory is complex, in that memory impairments can occur in response to manipulations that either increase or decrease GC levels. We investigated this issue by assessing the relationship between serum corticosterone (the primary rodent GC) and memory in rats trained in the radial arm water maze, a hippocampus-dependent spatial memory task. Each day, rats learned a new location of the hidden escape platform and then 30 min later their memory of the location of the platform was tested. Under control conditions, well-trained rats had excellent spatial memory and moderately elevated corticosterone levels (~26 μg/dl versus a baseline of ~2 μg/dl). Their memory was impaired when corticosterone levels were either reduced by metyrapone (a corticosterone synthesis inhibitor) or increased by acute stress (predator exposure), forming an overall U-shaped relationship between corticosterone levels and memory. We then addressed whether there was a causal relationship between elevated corticosterone levels and impaired memory. If elevated corticosterone levels were a sufficient condition to impair memory, then exogenously administered corticosterone, alone, should have impaired performance. However, we found that spatial memory was not impaired in corticosterone-injected rats that were not exposed to the cat. This work demonstrates that an intermediate level of corticosterone correlated with optimal memory, and either a decrease or an increase in corticosterone levels, in conjunction with strong emotionality, impaired spatial memory. These findings indicate that fear-provoking conditions, which are known to engage the amygdala, interact with stress levels of corticosterone to influence hippocampal functioning

The Illiquidity of Corporate Bonds

This paper examines the illiquidity of corporate bonds and its asset-pricing implications. Using transactions data from 2003 to 2009, we show that the illiquidity in corporate bonds is substantial, significantly greater than what can be explained by bid–ask spreads. We establish a strong link between bond illiquidity and bond prices. In aggregate, changes in market-level illiquidity explain a substantial part of the time variation in yield spreads of high-rated (AAA through A) bonds, overshadowing the credit risk component. In the cross-section, the bond-level illiquidity measure explains individual bond yield spreads with large economic significance.Charles A. Dice Center for Research in Financial EconomicsJ.P. Morgan & Co

How the Subprime Crisis went global: Evidence from bank credit default swap spreads

How did the Subprime Crisis, a problem in a small corner of U.S. financial markets, affect the entire global banking system? To shed light on this question we use principal components analysis to identify common factors in the movement of banks' credit default swap spreads. We find that fortunes of international banks rise and fall together even in normal times along with short-term global economic prospects. But the importance of common factors rose steadily to exceptional levels from the outbreak of the Subprime Crisis to past the rescue of Bear Stearns, reflecting a diffuse sense that funding and credit risk was increasing. Following the failure of Lehman Brothers, the interdependencies briefly increased to a new high, before they fell back to the pre-Lehman elevated levels - but now they more clearly reflected heightened funding and counterparty risk. After Lehman's failure, the prospect of global recession became imminent, auguring the further deterioration of banks' loan portfolios. At this point the entire global financial system had become infected

Crummer/Suntrust Portfolio: Analysis and Recommendations [2008]

Unfavorable economic conditions have prompted the investment team to meet a short-term goal: preserve the value of the portfolio by reducing overall risk. A top down analysis of the current portfolio resulted in recommendations to change the portfolio by eliminating funds, investing in long term government bonds, TIPS and large cap value type securities. Allocations of securities was performed by either overweighting or underweighting a particular sector, depending on its historical and expected return during a recession. Individual securities were analyzed by our sector analystsand recommendations of hold, buy or sell were made. The outcome.... a robust portfolio, that will preserve its value during the recession by reducing its overall risk by 25%

Are CDS spreads predictable? An analysis of linear and non-linear forecasting models

We assess the statistical and economic performance of various forecasting models to predict the future values of the iTraxx index. We find that linear models outperform non-linear models out-of-sample. Some trading strategies based on forecasts generated by the linear models deliver positive Sharpe ratios

The determinants of credit spreads changes in global shipping bonds.

yesThis paper investigates whether bond, issuer, industry and macro-specific variables account for the observed variation of credit spreads’ changes of global shipping bond issues before and after the onset of the subprime financial crisis. Results show that conclusions as to the significant variables of spreads depend significantly on whether two-way clusteradjusted standard errors are utilized, thus rendering results in the extant literature ambigious. The main determinants of global cargo-carrying companies’ shipping bond spreads are found in this paper to be: the liquidity of the bond issue, the stock market’s volatility, the bond market’s cyclicality, freight earnings and the credit rating of the bond issue