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Search Results: 1 - 10 of 209977 matches for " Adrienne L. Harrison "
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Contralateral Ear Occlusion for Improving the Reliability of Otoacoustic Emission Screening Tests
Emily Papsin,Adrienne L. Harrison,Mattia Carraro,Robert V. Harrison
International Journal of Otolaryngology , 2014, DOI: 10.1155/2014/248187
Abstract: Newborn hearing screening is an established healthcare standard in many countries and testing is feasible using otoacoustic emission (OAE) recording. It is well documented that OAEs can be suppressed by acoustic stimulation of the ear contralateral to the test ear. In clinical otoacoustic emission testing carried out in a sound attenuating booth, ambient noise levels are low such that the efferent system is not activated. However in newborn hearing screening, OAEs are often recorded in hospital or clinic environments, where ambient noise levels can be 60–70?dB SPL. Thus, results in the test ear can be influenced by ambient noise stimulating the opposite ear. Surprisingly, in hearing screening protocols there are no recommendations for avoiding contralateral suppression, that is, protecting the opposite ear from noise by blocking the ear canal. In the present study we have compared transient evoked and distortion product OAEs measured with and without contralateral ear plugging, in environmental settings with ambient noise levels <25?dB SPL, 45?dB SPL, and 55?dB SPL. We found out that without contralateral ear occlusion, ambient noise levels above 55?dB SPL can significantly attenuate OAE signals. We strongly suggest contralateral ear occlusion in OAE based hearing screening in noisy environments. 1. Introduction Audiometric testing in general is best carried out in a low noise environment. Indeed most clinical testing is done in sound attenuating booths, where background noise levels are typically below 20?dB SPL (for frequencies of audiometric interest). For performing behavioral (pure tone and speech audiometry) and physiological tests (auditory evoked potentials and OAEs) the focus has been on maintaining a good signal to noise ratio for the test signals presented. The issue addressed in the present study pertains not to the test ear but to the contralateral ear that may or may not be occluded. In neonatal or newborn hearing screening with OAEs most protocols do not specify any occlusion or plugging of the nontest ear (e.g., [1–11]). However, such screening tests are routinely carried out in a noisy hospital or clinic environments. Newborn babies may be screened in patient’s rooms, clinical areas, or a neonatal intensive care unit (NICU), where ambient sound levels can be as high as 60–70?dB SPL (e.g., [12–16]). The American Academy of Pediatrics recommends that sound levels in an NICU should not exceed 45?dB, but most often this is not the case. Indeed a review by Konkani and Oakley reveals that ambient noise levels in typical NICUs can exceed 80?dB
The Age of Stupid
Adrienne Harrison
Amsterdam Law Forum , 2009,
Abstract: The Age of Stupid Written and Directed by: Franny Armstrong Produced by: Lizzie Gillet Released in September, 2009
Political Activism with an Environmentally-conscious Vision: an Interview with karim Maarek
Adrienne Harrison
Amsterdam Law Forum , 2010,
Abstract: Karim Maarek s a district representative of the environmentally-conscious Dutch political group, GroenLinks. I sat down with him to gather his perspective on climate change, Copenhagen and the general interplay of politics, law and environmentalism in The Netherlands
The Curse of the Golden Handcuffs: The Case for Reform In Tuition And Licensing Requirements for Lawyers in the US
Adrienne Harrison
Amsterdam Law Forum , 2010,
Abstract: This article discusses the shortfalls of pursuing a law degree (and, subsequently, a license to practice law) in the United States. While “golden handcuffs” generally refer to the policy of providing high pay and incentives to employees in order to deter them from leaving a company, this article submits that law school graduates face another kind of golden handcuff – investing time and money to complete the seemingly prestigious Juris Doctor degree only to be placed in the unfortunate position of not having many options to recoup the investment in the current economic crisis, or, for those fortunate enough to land a high-paying position, being shackled to the job for 80 plus hours a week for years at a time.
Editorial
Leslie Flemming,Adrienne Harrison
Amsterdam Law Forum , 2010,
Abstract: From December 7-18, 2009, delegates from 194 nations met in attempt to reach an agreement that would slow climate change and increase environmental responsibility. Ultimately, what resulted was the Copenhagen Accord. This relatively brief, non-binding document (drafted by only a handful of delegates) recognizes "the scientific view that the increase in global temperature should be below 2 degrees Celsius", and aims to raise $100 billion per year from “a wide variety of sources” to help developing nations cut carbon emissions. But with no indication as to how greenhouse gasses will be minimized, or how $100 billion will be raised and distributed, it is difficult to see the Copenhagen Accord as much more than a list of nice ideas.
The Dark Matter Annihilation Boost from Low-Temperature Reheating
Adrienne L. Erickcek
Physics , 2015, DOI: 10.1103/PhysRevD.92.103505
Abstract: The evolution of the Universe between inflation and the onset of big bang nucleosynthesis is difficult to probe and largely unconstrained. This ignorance profoundly limits our understanding of dark matter: we cannot calculate its thermal relic abundance without knowing when the Universe became radiation dominated. Fortunately, small-scale density perturbations provide a probe of the early Universe that could break this degeneracy. If dark matter is a thermal relic, density perturbations that enter the horizon during an early matter-dominated era grow linearly with the scale factor prior to reheating. The resulting abundance of substructure boosts the annihilation rate by several orders of magnitude, which can compensate for the smaller annihilation cross sections that are required to generate the observed dark matter density in these scenarios. In particular, thermal relics with masses less than a TeV that thermally and kinetically decouple prior to reheating may already be ruled out by Fermi-LAT observations of dwarf spheroidal galaxies. Although these constraints are subject to uncertainties regarding the internal structure of the microhalos that form from the enhanced perturbations, they open up the possibility of using gamma-ray observations to learn about the reheating of the Universe.
Community structure in introductory physics course networks
Adrienne L. Traxler
Physics , 2015,
Abstract: Student-to-student interactions are foundational to many active learning environments, but are most often studied using qualitative methods. Network analysis tools provide a quantitative complement to this picture, allowing researchers to describe the social interactions of whole classrooms as systems. Past results from introductory physics courses have suggested a sharp division in the formation of social structure between large lecture sections and small studio classroom environments. Extending those results, this study focuses on calculus-based introductory physics courses at a large public university with a heavily commuter and nontraditional student population. Community detection network methods are used to characterize pre- and post-course collaborative structure in several sections, and differences are considered between small and large classes. These results are compared with expectations from earlier findings, and comment on implications for instruction and further study.
Development of a Reproducible Rating System for Sun Protective Clothing That Incorporates Body Surface Coverage  [PDF]
Simone L. Harrison, Nathan Downs
World Journal of Engineering and Technology (WJET) , 2015, DOI: 10.4236/wjet.2015.33C031
Abstract:

Sunlight is a known skin carcinogen. Skin cancer is the most common form of cancer in humans, and typically affects sun-exposed parts of the body. Sunny Australia and New Zealand have the highest incidence of skin cancer globally. Clothing provides a protective barrier that reduces the amount of ultraviolet radiation (UVR) reaching the skin. Australia pioneered the development of a relative ranking of the sun-protective capabilities of clothing based on the transmission of UVR through fabric. Standardized Ultraviolet Protection Factor (UPF) measurement procedures and associated labeling specifications are documented in the Australian and New Zealand Standard, AS/NZS 4399:1996. The standard was intended to enable consumers to make informed choices. Since its introduction, this standard has been adopted almost universally by the textile industry, and is still in use almost two decades on, with plans to revise it only commencing recently. However, AS/NZS 4399:1996 does not consider garment design, particularly in relation to body surface coverage. Although swim-shirts have grown in popularity in Australia since the late 1990s, particularly among children, clothing remains under-utilized as a form of sun-protection in contemporary society. Skin cancer prevention campaigns should emphasize the sun-protective benefits of clothing and collaboration with the fashion industry is urgently needed to improve the aesthetic appeal, comfort, durability and affordability of sun-protective clothing to increase its popularity in skin cancer prone populations. In light of recent evidence showing that high UPF clothing which covers more of the body surface reduces pigmented mole development in children (major risk factor for melanoma), the rating system for sun-protective clothing should incorporate body surface covered as well as the UPF of the fabric. We discuss progress towards developing a protocol for measuring the extent of coverage of sun-protective garments. Once fully evaluated and refined, the testing protocol developed from this research may influence future revisions of international standards for evaluating and classifying sun-protective clothing.

Reheating Effects in the Matter Power Spectrum and Implications for Substructure
Adrienne L. Erickcek,Kris Sigurdson
Physics , 2011, DOI: 10.1103/PhysRevD.84.083503
Abstract: The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cutoff in the matter power spectrum. Conversely, for dark matter produced nonthermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M > 0.1 Earth masses at z=100, compared to a fraction of 1e-10 in the standard case. In this scenario, ultradense substructures may constitute a large fraction of dark matter in galaxies today.
An equity investigation of attitudinal shifts in introductory physics
Adrienne L. Traxler,Eric Brewe
Physics , 2014, DOI: 10.1103/PhysRevSTPER.11.020132
Abstract: We report on seven years of attitudinal data using the Colorado Learning Attitudes about Science Survey from University Modeling Instruction (UMI) sections of introductory physics at Florida International University. This work expands upon previous studies that reported consistently positive attitude shifts in UMI courses; here, we disaggregate the data by gender and ethnicity to look for any disparities in the pattern of favorable shifts. We find that women and students from statistically underrepresented ethnic groups are equally supported on this attitudinal measure, and that this result holds even when interaction effects of gender and ethnicity are included. We conclude with suggestions for future work in UMI courses and for attitudinal equity investigations generally.
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