Approaches for modeling magnetic nanoparticle dynamics

Magnetic nanoparticles are useful biological probes as well as therapeutic agents. There have been several approaches used to model nanoparticle magnetization dynamics for both Brownian as well as N\'eel rotation. The magnetizations are often of interest and can be compared with experimental results. Here we summarize these approaches including the Stoner-Wohlfarth approach, and stochastic approaches including thermal fluctuations. Non-equilibrium related temperature effects can be described by a distribution function approach (Fokker-Planck equation) or a stochastic differential equation (Langevin equation). Approximate models in several regimes can be derived from these general approaches to simplify implementation

Security Transaction Taxes and Market Quality

We examine nine changes in the New York State Security Transaction Taxes (STT) between 1932 and 1981. We find that imposing or increasing an STT results in wider bidask spreads, lower volume, and increased price impact of trades. In contrast to theories of STT imposition as a means to reduce volatility, we find no consistent relationship between the level of an STT and volatility. We examine the propensity of traders to switch trading locations to avoid the tax and find no consistent evidence that they will change locations. We do find evidence to suggest that taxes imposed on the par value of stock will result in corporations managing the par value in the direction of minimizing the impact of the tax on investors.Econometric and statistical methods; Financial markets; Market structure and pricing

Robert Nathaniel Dett and the Music of the Harlem Renaissance

While the contributions of writers and poets to the period of American cultural history known as the Harlem Renaissance are relatively well defined and understood, assessing the contributions of musicians has been more problematic. The topic has been covered indirectly through works of American music history and African American history, but there have been comparatively few works linking music directly to the goals of the movement. Much of the insight into music’s place during this period derives from contemporary writers such as Alain Locke and James Weldon Johnson, both of whom featured discussions of music in their writings. Relatively unknown today, Robert Nathaniel Dett (1882-1943) was one of a group of composers whose work reflects the goals of Locke and other Renaissance writers. This thesis will explore the work of Robert Nathaniel Dett as a composer and educator in the larger context of the Harlem Renaissance. With in-depth biographies of Dett’s life already available, this thesis will focus on the period of his greatest activity during the 1910s and the 1920s while concurrently attempting to establish a larger context for his work by situating it within the course of American music history of the period. Specific topics will include: Dett’s education at Oberlin College and subsequent employment as Music Director at Hampton Institute; how characteristics of Dett’s music aligned with the goals of the Harlem Renaissance; and, Dett’s response to criticism that he was neglecting the authentic heritage of African American music

Paying for Market Quality

One way to improve the liquidity of small stocks is to subsidize the providers of liquidity. These subsidies take many forms such as informational advantages, priority in trading with incoming order flow, and fee rebates for limit order traders. In this study, we examine another type of subsidy – directly paying liquidity providers to provide contractual improvement in liquidity. Our specific focus here is the 2002 decision by the Stockholm Stock Exchange to allow listed firms to negotiate with liquidity providers to set maximum spread widths and minimum depths. We find, for a sample of stocks that entered into such an arrangement, a significant improvement in market quality with a decline in quoted spreads and an increase in quoted depth throughout the limit order book. We also find evidence that suggests that there are improvements beyond those contracted for. In addition, both inter and intraday volatility decline following the entry of committed liquidity providers for these stocks. Traders benefit by the reduced costs as well as by the ease of finding liquidity as seen in the increased trade sizes. We also find that a firm’s stock price subsequent to entering into the agreement rises in direct proportion to the improvement in market quality Thus, we find overwhelming evidence of liquidity benefits to listed firms of entering into such contracts which suggests that firms should consider these market quality improvement opportunities as they do other capital budgeting decisions and that there are residual benefits beyond those contracted for.No keywords;

Postmodern Messiah: A Critical Ethnography of Elvis Presley as a Site of Performance.

In this study I used a critical ethnographic approach to investigate Elvis as a site of performance where cultural identity, authority and representation are contextualized within the cultural practices of fans, people who love Elvis, and funs, people who do not love Elvis, but still elect to use Elvis as the basis for their cultural performances. I argued that fans and funs use performance as the agency of postmodern identity construction. I explored three performance events in which both fans and funs participated. Additionally, I examined the relationship of power and play between and within fan and fun culture. I positioned fan and fun activities as cultural performances that enact political ideologies supported by members of fan and fun cultures. I focused on fans and funs as performers who enacted material, verbal, and processual texts. I detailed these performances in three case studies. In the first case study, written as a narrative, I discussed the performance of the Candlelight Vigil. I described the Vigil as a ritual and discussed how fans/funs use the performance to enact power relations within and between each culture. I also considered how performance of the Vigil aids postmodern identity construction for fans and funs. In the next case study, written as a screenplay, I critiqued the performance of the Graceland Mansion tour. I discussed how fans and funs are special types of tourists who use the tour context to further their own cultural identities and agendas. Finally, in the last case study I explored the critical implications of shopping for souvenirs as performance. I wrote the first part of the study as a brochure to highlight the rhetoric of objects featured at Graceland Plaza. The second part of the chapter I wrote as a scrapbook of snapshots to implicate my own autobiographical experience of shopping at Graceland Crossings in the same context as popular and academic discourse about souvenirs and shopping. I attempted to draw the connection between myself and fan/fun performances of shopping at both venues to determine if shopping was an empowering or disempowering performance of postmodern identity

Sea Lamprey (Petromyzon marinus) as a Functional Link between Marine and Freshwater Ecosystems

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase. Historically, marine and freshwater ecosystems were linked by migrating anadromous fish, including sea lamprey. However, barriers such as dams have reduced or eliminated these migrations and therefore the delivery of nutrients via metabolic waste, eggs, and carcasses to recipient freshwater systems. This thesis generally focused on characterizing the dynamics and delivery of nutrients from sea lamprey, the pathways by which these nutrients may be assimilated in stream food webs, and factors that may alter or influence these effects. A first step to understanding the role of sea lamprey in freshwater food webs is to characterize the composition of adult tissue and subsequent dynamics of decomposition and nutrient liberation. First, the timing of decomposition and subsequent nutrient liberation of sea lamprey carcasses was characterized with a field and laboratory experiment. Elemental composition revealed lamprey carcass nitrogen:phosphorus ratios of 20.2:1 (± 1.18 SE). The experiments demonstrated that carcasses exponentially decompose over a three to four week period in the stream leaving 27% (± 3.0% SE) of the initial biomass remaining and liberating the majority of phosphorus and nitrogen. These experiments characterize the dynamics of nutrients delivered to freshwater systems and suggest that these subsidies may serve to enrich stream food webs and alleviate nutrient limitations. The spatial and temporal dynamics of sea lamprey carcass nutrients were examined. Carcass addition experiments were conducted to examine changes in stream nutrients, primary productivity, and nutrient assimilation among consumers. Field experiments revealed 57–71% increases in algal biomass in areas with experimentally added sea lamprey carcasses compared to an upstream reference. However, broader spatial changes from multiple-site carcass addition may have been influenced by canopy cover from adjacent riparian vegetation that limit incoming sunlight to the stream. Several macroinvertebrate families including Heptageniidae, Hydropsychidae, and Perlidae assimilated carcass nutrients, as determined with stable isotopes analysis. Results from these experiments suggest that carcass nutrients may evoke localized effects on food webs, and the pathways of assimilation by organisms may be coupled to adjacent terrestrial systems. Resource flows from sea lamprey across ecosystem boundaries may subsidize recipient communities and influence bottom-up and top-down processes in food webs. However, dams and barriers to fish passage may limit returns of spawning adult sea lamprey to freshwater streams. Carcass addition experiments tested the effects of a gradient of increasing carcass nutrients on primary producers and decomposers in stream reaches flowing through open and closed riparian forest canopies. These experiments revealed that manipulating the quantity of nutrient resources affected producers and decomposers differently and that trends were further influenced by adjacent terrestrial systems. A carcass addition experiment also revealed that larval lamprey assimilate a portion of carcass nutrients. Therefore, collectively these experiments demonstrate that sea lamprey carcasses may stimulate bottom-up trophic dynamics by alleviating nutrient limitations, and additionally these nutrients may be captured by higher trophic levels. This suggests that cross-ecosystem linkages may be mediated by subsidy quantity from donor systems and environmental characteristics from recipient systems. Sea lamprey function as an ecosystem engineer through nest building and spawning activities and as a vector of nutrients to freshwater systems. Macroinvertebrates, an important intermediate pathway in the cycling of nutrients and transfer of energy, may be influenced by these physical and chemical perturbations. We examined the colonization of macroinvertebrate assemblages on cleaned coarse substrate designed to mimic substrate modified by sea lamprey spawning and subsequent nutrient enrichment from post-spawned sea lamprey carcasses. We found that abundance and biomass in sites receiving carcass nutrients were structured largely by Simuliidae, compared to control sites that were structured by Hydropsychidae, Philopotamidae, and Chironomidae. Environmental factors such as stream flow may further shape assemblages by physically constraining the foraging capabilities of certain macroinvertebrate families. Larval sea lamprey reside in streams for 6–8 years to upwards of 14 years and function as a filter feeding detritivore and utilize nutrients from adult carcasses. As a result, larvae may exhibit higher growth rates during the post-spawn period of increasing temperatures and nutrient limitation. The sensitivity of life history parameters and influence of sea lamprey carcass nutrients on the age and growth of larval conspecifics was examined with a deterministic stock recruitment model. Larval populations receiving carcass nutrients demonstrated increases in larval growth and lower age-at-metamorphosis that, over time, resulted in a 3 fold increase in the numbers of returning adults to freshwaters. This model exemplifies two potential alternative ecosystem states, one in which fish populations are uninhibited during migration, and another in which fish passage is constrained by migratory barriers

Survey of Pharmacology Education in Entry-Level Physical Therapy Programs

The purpose of this survey research is to document the current status of education in pharmacology in the curriculum of entry-level physical therapy programs. A questionnaire was sent to the 135 entry-level physical therapy programs located in the United States and accredited by the American Physical Therapy Association. The director or faculty member responsible for pharmacology instruction in 96 (71.1 %) of the entry-level physical therapy programs participated in the five-part survey. The questionnaire results indicate that nearly all of the program respondents (98.9%) incorporate pharmacology content into existing required courses and/or have in his or her curriculum a required course specifically in pharmacology. The majority of the respondents (61.5%) perceive their program adequately covers the topic of pharmacology for the entry-level physical therapy graduate. The lack of time or space within an existing curriculum was the most frequently listed factor prohibiting improvement. Suggestions for improving future entry-level physical therapy education in pharmacology are given