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These collections include publications and data from University of Arizona faculty, staff and researchers. The UA Faculty Publications collection consists primarily of open access versions of published journal articles, but also contains conference proceedings and other unique materials from faculty, staff and researchers. Organizational collections, such as the College of Agricultural and Life Sciences Publications, and Water Resources Research Center, contain additional faculty publications such as departmentally produced technical bulletins, technical reports, and working papers.
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Linguistic Change and the Future of Metrical Persian PoetryThe metrical requirements of Persian poetry are highly restrictive. Traditionally, the rigidity of the metrical system was compensated for by a high degree of flexibility in the poetic language in terms of lexicon, phonology, and morpho-syntax. Using statistical data from different periods of Persian poetry, this paper argues that the degree of flexibility of the language used in metrical Persian poetry has been in constant decrease, moving towards what may potentially be a language crisis for metrical Persian poetry. This study traces the linguistic and meta-linguistic origins of the initial flexibility of the poetic language and its subsequent change, suggesting that some of the recent trends in Persian poetry may be viewed in part as reactions to this potential crisis.
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Quantum-optimal detection of one-versus-two incoherent optical sources with arbitrary separationWe analyze the fundamental quantum limit of the resolution of an optical imaging system from the perspective of the detection problem of deciding whether the optical field in the image plane is generated by one incoherent on-axis source with brightness. or by two epsilon/2-brightness incoherent sources that are symmetrically disposed about the optical axis. Using the exact thermal-state model of the field, we derive the quantum Chernoff bound for the detection problem, which specifies the optimum rate of decay of the error probability with increasing number of collected photons that is allowed by quantum mechanics. We then show that recently proposed linear-optic schemes approach the quantum Chernoff bound-the method of binary spatial-mode demultiplexing (B-SPADE) is quantum-optimal for all values of separation, while a method using image inversion interferometry (SLIVER) is near-optimal for sub-Rayleigh separations. We then simplify our model using a low-brightness approximation that is very accurate for optical microscopy and astronomy, derive quantum Chernoff bounds conditional on the number of photons detected, and show the optimality of our schemes in this conditional detection paradigm. For comparison, we analytically demonstrate the superior scaling of the Chernoff bound for our schemes with source separation relative to that of spatially resolved direct imaging. Our schemes have the advantages over the quantum-optimal (Helstrom) measurement in that they do not involve joint measurements over multiple modes, and that they do not require the angular separation for the two-source hypothesis to be given a priori and can offer that information as a bonus in the event of a successful detection.
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The Origins Space Telescope: mission concept overviewThe Origins Space Telescope (OST) will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did the universe evolve in response to its changing ingredients? How common are life-bearing planets? To accomplish its scientific objectives, OST will operate at mid-and far-infrared wavelengths and offer superlative sensitivity and new spectroscopic capabilities. The OST study team will present a scientifically compelling, executable mission concept to the 2020 Decadal Survey in Astrophysics. To understand the concept solution space, our team studied two alternative mission concepts. We report on the study approach and describe both of these concepts, give the rationale for major design decisions, and briefly describe the mission-enabling technology.
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The impact of state laws on motor vehicle fatality rates, 1999-2015BACKGROUND Motor vehicle crash (MVC) fatalities have been declining while states passed various legislation targeting driver behaviors. This study assesses the impact of state laws on MVC fatality rates to determine which laws were effective. METHODS Publically available data were collected on driver-related motor vehicle laws, law strengths, enactment years, and numbers of verified-trauma centers. Prospective data on crash characteristics and MVC fatalities 16 years or older from Fatality Analysis Reporting System 1999 to 2015 (n = 850) were obtained. Generalize Linear Autoregressive Modeling was used to assess the relative contribution of state laws to the crude MVC fatality rate while controlling for other factors. RESULTS Lowering the minimum blood alcohol content (BAC) was associated with largest declines for all ages, especially the older cohorts: 16 years to 20 years (B= 0.23;p< 0.001), 21 years to 55 years (B= 1.7;p< 0.001); 56 years to 65 years (B= 3.2;p< 0.001); older than 65 years (B= 4.1;p< 0.001). Other driving under the influence laws were also significant. Per se BAC laws accompanying a reduced BAC further contributed to declines in crude fatality rates: 21 years to 55 years (B = -0.13;p< 0.001); older than 65 years (B= -0.17;p< 0.05). Driving under the influence laws enhancing the penalties, making revocation automatic, or targeting social hosts had mixed effects by age. Increased enforcement, mandatory education, vehicle impoundment, interlock devices, and underage alcohol laws showed no association with declining mortality rates. Red light camera and seatbelt laws were associated with declines in mortality rates for all ages except for older than 65 years cohort, but speed camera laws had no effect. Graduated Driver License laws were associated with declines for 16 years to 21 years (B= -0.06;p< 0.001) only. Laws targeting specific risks (elderly, motorcycles, marijuana) showed no effect on declining MVC mortality rates during the study period. CONCLUSION States have passed a wide variety of laws with varying effectiveness. A few key laws, specifically laws lowering allowable BAC, implementing red light cameras, and mandating seatbelt use significantly reduced MVC mortality rates from 1999 to 2015. Simply adding more laws/penalties may not equate directly to lives saved. Continued research on state laws will better inform policy makers to meet evolving public health needs in the management of MVC fatalities.
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Medical Overtesting and Racial DistrustThe phenomenon of medical overtesting in general, and specifically in the emergency room, is well known and regarded as harmful to both the patient and the healthcare system. Although the implications of this problem raise myriad ethical concerns, this paper explores the extent to which overtesting might mitigate race-based health inequalities. Given that medical malpractice and error greatly increase when the patients belong to a racial minority, it is no surprise that the mortality rate similarly increases in proportion to white patients. For these populations, an environment that emphasizes medical overtesting may well be the desirable medical environment until care evens out among races and ethnicities; additionally, efforts to lower overtesting in conjunction with a high rate of racist medical mythology may cause harm by lowering testing when it is actually warranted. Furthermore, medical overtesting may help to assuage racial distrust. This paper ultimately concludes that an environment of medical overtesting may be less pernicious than the alternative.
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Rural Bioethics: The Alaska ContextWith by far the lowest population density in the United States, myriad challenges attach to healthcare delivery in Alaska. In the “Size, Population, and (In)Accessibility” section, we characterize this geographic context, including how it is exacerbated by lack of infrastructure. In the “Distributing Healthcare” section, we turn to healthcare economics and staffing, showing how these bear on delivery—and are exacerbated by geography. In the “Health Care in Rural Alaska” section, we turn to rural care, exploring in more depth what healthcare delivery looks like outside of Alaska’s major cities. This discussion continues in the “Alaska’s Native Villages” section, which specifically analyzes healthcare in Alaska’s indigenous villages, some of the smallest and most isolated communities in the United States. Though many of the ways we could improve Alaskan health care for Alaskan residents are limited by its unique features, the “Justice and Healthcare Delivery” and “Technology and Telemedicine” sections consider ways in which certain policies and technology—including telemedicine—could mitigate the challenges developed in previous sections.
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A Fatal Nest Construction: Man-mixed Cement Used by Mud-daubing WaspsSome sphecid wasps apparently show tolerance to urban habitats. However, resilience to man-made environments may have harmful consequences when behavioral errors can lead to ecological traps. We report failures in nesting construction of Sceliphron jamaicense by erroneous choosing of building material (i.e. mud). We found a proportion of nests (1.26%)where the wasps used both mud and concrete to seal the nests. Consequently, the brood was unable to emerge through the hardened material. It seems that the discrimination between building materials appears to be poor in these hymenopterans. Such ecological traps could have long term negative consequences around urban environments.
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High-Throughput Phenotyping of Crop Water Use Efficiency via Multispectral Drone Imagery and a Daily Soil Water Balance ModelImprovement of crop water use efficiency (CWUE), defined as crop yield per volume of water used, is an important goal for both crop management and breeding. While many technologies have been developed for measuring crop water use in crop management studies, rarely have these techniques been applied at the scale of breeding plots. The objective was to develop a high-throughput methodology for quantifying water use in a cotton breeding trial at Maricopa, AZ, USA in 2016 and 2017, using evapotranspiration (ET) measurements from a co-located irrigation management trial to evaluate the approach. Approximately weekly overflights with an unmanned aerial system provided multispectral imagery from which plot-level fractional vegetation cover (f(c)) was computed. The f(c) data were used to drive a daily ET-based soil water balance model for seasonal crop water use quantification. A mixed model statistical analysis demonstrated that differences in ET and CWUE could be discriminated among eight cotton varieties (p < 0.05), which were sown at two planting dates and managed with four irrigation levels. The results permitted breeders to identify cotton varieties with more favorable water use characteristics and higher CWUE, indicating that the methodology could become a useful tool for breeding selection.
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In-Flight Calibration and Performance of the OSIRIS-REx Visible and IR Spectrometer (OVIRS)Performance of the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) Visible and InfraRed Spectrometer (OVIRS) instrument was validated, showing that it met all science requirements during extensive thermal vacuum ground testing. Preliminary instrument radiometric calibration coefficients and wavelength mapping were also determined before instrument delivery and launch using NIST-traceable sources. One year after launch, Earth flyby data were used to refine the wavelength map by comparing OVIRS spectra with atmospheric models. Near-simultaneous data from other Earth-orbiting satellites were used to cross-calibrate the OVIRS absolute radiometric response, particularly at visible wavelengths. Trending data from internal calibration sources and the Sun show that instrument radiometric performance has been stable to better than 1% in the 18 months since launch.
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Determining Subarctic Peatland Vegetation Using an Unmanned Aerial System (UAS)Rising global temperatures tied to increases in greenhouse gas emissions are impacting high latitude regions, leading to changes in vegetation composition and feedbacks to climate through increased methane (CH4) emissions. In subarctic peatlands, permafrost collapse has led to shifts in vegetation species on landscape scales with high spatial heterogeneity. Our goal was to provide a baseline for vegetation distribution related to permafrost collapse and changes in biogeochemical processes. We collected unmanned aerial system (UAS) imagery at Stordalen Mire, Abisko, Sweden to classify vegetation cover types. A series of digital image processing routines were used to generate texture attributes within the image for the purpose of characterizing vegetative cover types. An artificial neural network (ANN) was developed to classify the image. The ANN used all texture variables and color bands (three spectral bands and six metrics) to generate a probability map for each of the eight cover classes. We used the highest probability for a class at each pixel to designate the cover type in the final map. Our overall misclassification rate was 32%, while omission and commission error by class ranged from 0% to 50%. We found that within our area of interest, cover classes most indicative of underlying permafrost (hummock and tall shrub) comprised 43.9% percent of the landscape. Our effort showed the capability of an ANN applied to UAS high-resolution imagery to develop a classification that focuses on vegetation types associated with permafrost status and therefore potentially changes in greenhouse gas exchange. We also used a method to examine the multiple probabilities representing cover class prediction at the pixel level to examine model confusion. UAS image collection can be inexpensive and a repeatable avenue to determine vegetation change at high latitudes, which can further be used to estimate and scale corresponding changes in CH4 emissions.
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Universality, heterogeneity, and worlding: meanings of comparison in Chinese comparative literatureComparison, either in the methodological or ontological sense, is the soul and the operational principle of comparative literature. Its meaning, however, has not always been transparent nor unchanging in the Chinese context. Tracing its signifying trajectory from "universality" to "heterogeneity," the paper offers a mapping of historicity and culturality that underscores the Chinese theories of literature and the function of comparative literature as a discipline and as an instrument of intercultural communication. The authors further argue that the discourse of comparison, as a way of worlding, reflects a desire of Chinese comparatists to engage the world and yet to retain a distinctive theoretical space and discourse, in which the markings of a Chinese school can be inscribed.
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Cognitive characteristics of 8- to 10-week-old assistance dog puppiesTo characterize the early ontogeny of dog cognition, we tested 168 domestic dog, Canis familiaris, puppies (97 females, 71 males; mean age = 9.2 weeks) in a novel test battery based on previous tasks developed and employed with adolescent and adult dogs. Our sample consisted of Labrador retrievers, golden retrievers and Labrador x golden retriever crosses from 65 different litters at Canine Companions for Independence, an organization that breeds, trains and places assistance dogs for people with disabilities. Puppies participated in a 3-day cognitive battery that consisted of 14 tasks measuring different cognitive abilities and temperament traits such as executive function (e.g. inhibitory control, reversal learning, working memory), use of social cues, sensory discriminations and reactivity to and recovery from novel situations. At 8-10 weeks of age, and despite minimal experience with humans, puppies reliably used a variety of cooperative-communicative gestures from humans. Puppies accurately remembered the location of hidden food for delays of up to 20 s, and succeeded in a variety of visual, olfactory and auditory discrimination problems. They also showed some skill at executive function tasks requiring inhibitory control and reversal learning, although they scored lower on these tasks than is typical in adulthood. Taken together, our results confirm the early emergence of sensitivity to human communication in dogs and contextualize these skills within a broad array of other cognitive abilities measured at the same stage of ontogeny. (C) 2020 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
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Intelligent-CW: AI-based Framework for Controlling Contention Window in WLANsThe heterogeneity of technologies that operate over the unlicensed 5 GHz spectrum, such as LTE-Licensed-Assisted-Access (LAA), 5G New Radio Unlicensed (NR-U), and Wi-Fi, calls for more intelligent and efficient techniques to coordinate channel access beyond what current standards offer. Wi-Fi standards require nodes to adopt a fixed value for the minimum contention window (CWmin), which prohibits a node from reacting to aggressive nodes that set their CWmin to small values. To address this problem, we propose a framework called Intelligent-CW (ICW) that allows nodes to adapt their CWmin values based on observed transmissions, ensuring they receive their fair share of the channel airtime. The CWmin value at a node is set based on a random forest, a machine learning model that includes a large number of decision trees. We train the random forest in a supervised manner over a large number of WLAN scenarios, including different misbehaving and aggressive scenarios. Under aggressive scenarios, our simulation results reveal that ICW provides nodes with higher throughput (153.9% gain) and 64% lower frame latency than standard techniques. In order to measure the fairness contribution of individual nodes, we introduce a new fairness metric. Based on this metric, ICW is shown to provide 10.89x improvement in fairness in aggressive scenarios compared to standard techniques.
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International Graduate Student Labor as Mergers and AcquisitionsThis study critically examines the self-reported experiences of international graduate students using a framework understanding internationalization as acquisitions and mergers. Students reported positive experiences with their advisors. However, students' accounts of laboratories and other research settings were diverse, ranging from co-contributors to knowledge and respected collaborators to employed cheap labor that their advisors depended upon for their own gains. In some cases, these students feared that their funding would be cut off or dismissed from the program (and consequently deported from the US) if they challenged their advisors. Whether such apprehensions were valid is unknown as this study focused on perceptions of the students only. The findings do lead to important future directions for research and practice.
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Characterization of basin-scale aquifer heterogeneity using transient hydraulic tomography with aquifer responses induced by groundwater exploitation reductionThis study exploits aquifer responses to the reduction of pumping rates at different locations in a synthetic groundwater basin as basin-scale hydraulic tomography (HT) surveys to estimate transmissivity (T) and storage coefficient (S) fields. This experiment mimics the situation of groundwater exploitation reduction in a pilot area of groundwater-overexploitation control in the North China Plain. The results of the study show that taking advantage of the groundwater exploitation reduction as HT surveys is a viable approach for basin-scale parameter estimations. Results also suggest that HT analysis should use accurate mean values of T and S for geological zones as initial guesses for the inversion of parameters. Further, we show that the T and S fields estimated from HT yield accurate predictions of the groundwater flow velocities and breakthrough curves (BTCs). However, the BTCs based on kriged and zonal mean fields are inaccurate. The predicted BTCs using homogeneous fields fail to capture the true trend of solute concentration over time. We advocate that utilizing aquifer responses induced by groundwater exploitation reduction could be a new paradigm for basin-scale aquifer characterization.
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Reportage from Blotetown: Yisroel-Yoysef Zevin (Tashrak) and the Shtetlization of New York CityThe neglected-but-popular Yiddish humorist Tashrak (penname of Yisroel-Yoysef Zevin) offers not just an opportunity to discover understudied aspects of the Jewish urban experience and modern Yiddish culture, but also allows us to tap into a less refined level of beliefs, behavior, judgments and attitudes of Yiddish-speaking Jews in America. Tashrak wittily conveyed to his readers a comforting image of the New World: New York City was just an enlarged shtetl, whose Jewish residents clashed over a host of issues, while encountering a number of stereotypical non-Jews. In his representation of internal Jewish divisions and disputes, relations with non-Jews, and the trials of modernity and assimilation, Tashrak followed, to some extent, the literary paths of earlier Yiddish and Hebrew writers. Yet critics often frowned upon his politics as either conservative or apolitical, and considered his literary style as lowbrow, thus they disregarded his work altogether, or referred to it as worthless.
