The massless Thirring model in spherical field theory

We use the massless Thirring model to demonstrate a new approach to non-perturbative fermion calculations based on the spherical field formalism. The methods we present are free from the problems of fermion doubling and difficulties associated with integrating out massless fermions. Using a non-perturbative regularization, we compute the two-point correlator and find agreement with the known analytic solution.Comment: 11 pages, 2 figures, journal versio

Practical design issues for snapshot Mueller matrix spectropolarimetry

We discuss practical design constraints for snapshot Mueller matrix spectropolarimeters, and reveal a robustness problem with existing designs. By carefully choosing the ratios of thicknesses between the four thick retarders used in these systems, we can avoid requiring extremely tight tolerances, though at a cost in overall bandwidth. We provide example designs and quantify the robustness-resolution tradeoff.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Deciphering Pancharatnam's discovery of geometric phase

While Pancharatnam discovered the geometric phase in 1956, his work was not widely recognized until its endorsement by Berry in 1987, after which it received wide appreciation. However, because Pancharatnam's paper is unusually difficult to follow, his work has often been misinterpreted as referring to an evolution of states of polarization, just as Berry's work focused on a cycle of states, even though this consideration does not appear in Pancharatnam's work. We walk the reader through Pancharatnam's original derivation and show how Pancharatnam's approach connects to recent work in geometric phase. It is our hope to make this widely cited classic paper more accessible and better understood

Dynamic calibration of a channeled spectropolarimeter for extended temperature stability

Channeled Spectropolarimeters (CHSP) are compact optical instruments that have potential for making precise polarization measurements without any moving parts. While most spectropolarimeters use rotating elements to make measurements, CHSPs use mechanically fixed thick retarders to modulate the Stokes vector onto the spectrum of light. In realistic applications, CHSPs must have calibration algorithms that give stable measurements in a variety of environmental conditions. Previous researchers developed a self-calibration algorithm that uses redundant channel information to compensate temperature-induced phase fluctuations in real-time without any additional reference measurements. In this paper we discuss the stability of the self-calibration technique. We identify a mathematical ambiguity in the algorithm that limits the range of temperatures over which the algorithm is stable. For a 60 lambda:120 lambda channeled spectropolarimeter with quartz retarders, the stable temperature range is only 27 degrees C and is not suitable for many applications outside of the laboratory. We propose and demonstrate a modified algorithm that uses the slope of the phase to remove the mathematical ambiguity and extend the temperature range of the system. The demonstration shows stable operation over a 41 degrees C temperature range and shows promise for increasing stability over a temperature range suitable for extreme terrestrial conditions.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Perianal basal cell carcinoma: a common cancer in an uncommon location.

This is a case of a perianal basal cell carcinoma, a common skin cancer in an unusual location. Our patient is a 67-year-old male with a perianal lesion. He first noticed this painless lesion 5 years prior to presentation and was having fecal incontinence and weight loss. He had a fully encompassing ulcerated lesion involving the entirety of the anal margin. We performed a biopsy that returned on pathology as a basal cell carcinoma. Due to the size of the lesion and his current nutritional status, it was determined to be unresectable. We were able to provide him with a diverting colostomy to address his incontinence and this allowed the patient to recover enough to undergo treatment with radiation (total of 5400 cGy). To our knowledge, this is the largest perianal basal cell carcinoma reported in the literature and an example of combining palliative surgery and radiation as a treatment option

Wave description of geometric phase

Since Pancharatnam's 1956 discovery of optical geometric phase, and Berry's 1984 discovery of geometric phase in quantum systems, researchers analyzing geometric phase have focused almost exclusively on algebraic approaches using the Jones calculus, or on spherical trigonometry approaches using the Poincar\'e sphere. The abstracted mathematics of the former, and the abstracted geometry of the latter, obscure the physical mechanism that generates geometric phase. We show that optical geometric phase derives entirely from the superposition of waves and the resulting shift in the location of the wave maximum. This wave-based model provides a way to visualize how geometric phase arises from relationships between waves, and from the transformations induced by optical elements. We also derive the relationship between the geometric phase of a wave by itself and the phase exhibited by an interferogram, and provide the conditions under which the two match one another

Genome assembly of the chemosynthetic endosymbiont of the hydrothermal vent snail Alviniconcha adamantis from the Mariana Arc

Chemosynthetic animal-microbe symbioses sustain hydrothermal vent communities in the global deep sea. In the Indo-Pacific Ocean, hydrothermal ecosystems are often dominated by gastropod species of the genus Alviniconcha, which live in association with chemosynthetic Gammaproteobacteria or Campylobacteria. While the symbiont genomes of most extant Alviniconcha species have been sequenced, no genome information is currently available for the gammaproteobacterial endosymbiont of Alviniconcha adamantis—a comparatively shallow living species that is thought to be the ancestor to all other present Alviniconcha lineages. Here, we report the first genome sequence for the symbiont of A. adamantis from the Chamorro Seamount at the Mariana Arc. Our phylogenomic analyses show that the A. adamantis symbiont is most closely related to Chromatiaceae endosymbionts of the hydrothermal vent snails Alviniconcha strummeri and Chrysomallon squamiferum, but represents a distinct bacterial species or possibly genus. Overall, the functional capacity of the A. adamantis symbiont appeared to be similar to other chemosynthetic Gammaproteobacteria, though several flagella and chemotaxis genes were detected, which are absent in other gammaproteobacterial Alviniconcha symbionts. These differences might suggest potential contrasts in symbiont transmission dynamics, host recognition, or nutrient transfer. Furthermore, an abundance of genes for ammonia transport and urea usage could indicate adaptations to the oligotrophic waters of the Mariana region, possibly via recycling of host- and environment-derived nitrogenous waste products. This genome assembly adds to the growing genomic resources for chemosynthetic bacteria from hydrothermal vents and will be valuable for future comparative genomic analyses assessing gene content evolution in relation to environment and symbiotic lifestyles

Increased Awareness: The Role of Education in Influencing Attitudes and Understanding of Nonmedical Prescription Stimulants use in Greek-life Associated Undergraduate Populations

Class of 2018 AbstractSpecific Aims: To explore whether educational intervention of university students would improve their knowledge and perceptions of prescription stimulants. Subjects: Students between the ages of 18-22 years old who are current and enrolled members of a Greek Life organization that is recognized by a land-grant university in the Southwest. Methods: Questionnaires administered during a scheduled Greek Life chapter meeting that collected pre-presentation knowledge on general stimulant and prescription stimulant knowledge with a follow-up post-presentation questionnaire; additional data concerning age, ethnicity, and year of study was also collected. Main Results: Questionnaires were completed by 45 men (mean age = 19.96; SD = 1.31; 62% white). No advancement of knowledge regarding general stimulant and prescription stimulant knowledge was observed from the data analysis (p = 0.55). Conclusions: Verbal educational intervention as a sole monotherapy was not sufficient in changing the knowledge or attitudes regarding stimulants for a small portion of undergraduate students currently enrolled at a land-grant university in the Southwest who are actively involved in recognized Greek Life organizations. More studies with larger sample size need to be performed.This item is part of the Pharmacy Student Research Projects collection, made available by the College of Pharmacy and the University Libraries at the University of Arizona. For more information about items in this collection, please contact Jennifer Martin, Librarian and Clinical Instructor, Pharmacy Practice and Science, [email protected]