Now showing items 8519-8538 of 11675

    • Q&A: Evolutionary capacitance

      Masel, Joanna; Ecology and Evolutionary Biology, University of Arizona, 1041 E. Lowell St, Tucson, AZ 84721, USA (BioMed Central, 2013)
    • QBO/solar modulation of the boreal winter Madden-Julian oscillation: A prediction for the coming solar minimum

      Hood, Lon L.; Univ Arizona, Lunar & Planetary Lab; Lunar and Planetary Laboratory; University of Arizona; Tucson Arizona USA (AMER GEOPHYSICAL UNION, 2017-04-28)
      The Madden-Julian oscillation (MJO), also known as the 30-60day oscillation, is the strongest of the intraseasonal climate oscillations in the tropics and has significant derivative effects on extratropical circulation and intraseasonal climate. It has recently been shown that the stratospheric quasi-biennial oscillation (QBO) modulates the amplitude of the boreal winter MJO such that MJO amplitudes are larger on average during the easterly phase (QBOE) than during the westerly phase (QBOW). A major possible mechanism is the decrease in static stability in the lowermost stratosphere under QBOE conditions resulting from relative upwelling associated with the QBO-induced meridional circulation. Here evidence is presented that tropical upwelling changes related to the 11year solar cycle also modulate the boreal winter MJO. Based on 37.3years of MJO amplitude data, the largest amplitudes and occurrence rates, and the weakest static stabilities in the tropical lower stratosphere, occur during the QBOE phase under solar minimum (SMIN) conditions while the smallest amplitudes and strongest static stabilities occur during the QBOW phase under solar maximum (SMAX) conditions. Conversely, when the QBO and solar forcings are opposed (QBOW/SMIN and QBOE/SMAX), the difference in occurrence rates becomes statistically insignificant. During the coming solar minimum, at least one additional winter in the QBOE/SMIN category should occur (possibly as early as 2017/2018) during which especially large MJO amplitudes are expected and an initial test of these results will be possible. Plain Language Summary An ongoing issue in climate science is the extent to which upper atmospheric processes, including solar forcing, can influence tropospheric climate. It has recently been shown that an internal oscillation of the stratosphere, the quasi-biennial oscillation, can modulate the amplitude and occurrence rate of intraseasonal climate oscillations in the tropical Pacific during northern winter. These intraseasonal oscillations, the most important of which is the 30-60day Madden-Julian oscillation, have significant derivative effects on climate outside of the tropics, including impacts on rainfall events over the continental United States. Here evidence is presented that the amplitude of the Madden-Julian oscillation during northern winter is also modulated by the 11year solar cycle. The modulation is such that amplitudes and occurrence rates are largest under solar minimum conditions when the quasi-biennial oscillation is in its easterly phase and smallest under solar maximum conditions when the quasi-biennial oscillation is in its westerly phase. However, the available time record (37.3years of satellite measurements) is limited. During the coming solar minimum, at least one additional winter in the solar minimum/easterly category should occur (possibly as early as 2017/2018) during which larger-than-average amplitudes are expected and an initial test of the proposed relationship will be possible.
    • QKD-enhanced Cybersecurity Protocols

      Djordjevic, I.B.; College of Engineering, University of Arizona (Institute of Electrical and Electronics Engineers Inc., 2021)
      Security of QKD is guaranteed by the quantum mechanics laws rather than unproven assumptions employed in computational cryptography. Unfortunately, the secret-key rates are way too low and transmission distances are limited. The post-quantum cryptography (PQC) is proposed as an alternative to QKD. However, the PQC protocols are based on conjecture that there are no polynomial time algorithms to break the PQC protocols. To overcome key challenges of both post-quantum cryptography and QKD, we propose to use the QKD only in initialization stage to set-up corresponding cybersecurity protocols. The proposed concept is applied to both computational security and PQC protocols. The proposed QKD-enhanced cybersecurity protocols are tolerant to attacks initiated by quantum computers. CCBYNCND
    • Quadratic mathematical modeling of sustainable dry beneficiation of kaolin

      Hayat, M.B.; Danishwar, M.; Hamid, A.; Zaid, M.M.; Emad, M.Z.; Department of Mining and Geological Engineering, The University of Arizona (MDPI AG, 2021)
      Clay minerals are one of the most utilized minerals among non-metals. These are hydrous aluminum silicates with a layer (sheet-like) structure. Kaolin is a hydrous aluminosilicate mineral with a thin platelet structure. Kaolin is extensively used in paper, paint, and many other industries. Wet processing of kaolin will not be sustainable over the long term because global freshwater resources are becoming scarce. Hence, a process is necessary that does not consume water during the beneficiation of kaolin. This study developed a dry beneficiation process for low-grade kaolin of 59.6%, with 12% quartz and about 6% titaniferous impurities from Nagar Parkar, Sindh province, Pakistan. To develop a size difference between kaolinite and impurities, steel balls clad with rubber were used as the grinding media in a selective grinding unit. Screens of 60 and 400 mesh were employed to classify the feed of air classifier. Oversize +60 mesh was reground, 400 to 60 mesh fractions were sent to an air classifier, and −400 mesh was considered to be a product with the grade and recovery of 90.6% and 20.5%, respectively. Air classifier experiments were designed using central composite design. An experiment using a fan speed of 1200 rpm and a shutter opening of 4.0 showed optimum results, with maximum kaolinite grade and recovery of 91.5% and 35.9%, respectively. The statistical models developed for grade and recovery predicted the optimum results at a fan speed of 1251 rpm and shutter opening of 3.3 with the maximum kaolinite grade recovery of 91.1% and 24.7%, respectively. The differences between experimental and predicted grade and recovery were 0.1% and 2.4%, respectively. The characterization results showed the total upgrade of kaolin from 59.6% to 91.2%, with 27.1% recovery. The designed methodology has the potential to improve the yield of the product by focusing on its recovery. Furthermore, the designed process can be improved by using different sized balls in the selective grinding unit. This beneficiation process can utilize more than one air classifier in series to achieve the targeted results. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
    • A qualitative analysis of vaccine decision makers' conceptualization and fostering of 'community engagement' in India

      Dutta, Tapati; Meyerson, Beth E; Agley, Jon; Barnes, Priscilla A; Sherwood-Laughlin, Catherine; Nicholson-Crotty, Jill; Univ Arizona, Coll Med, Coll Social & Behav Sci Family & Community Med, Southwest Inst Res Women (BMC, 2020-10-20)
      Background Globally, and in India, research has highlighted the importance of community engagement in achieving national vaccination goals and in promoting health equity. However, community engagement is not well-defined and remains an underutilized approach. There is also paucity of literature on community engagement's effectiveness in achieving vaccination outcomes. To address that gap, this study interviewed Indian vaccination decision makers to derive a shared understanding of the evolving conceptualization of community engagement, and how it has been fostered during India's Decade of Vaccines (2010-2020). Methods Semi-structured interviews were conducted with 25 purposefully sampled national-level vaccine decision makers in India, including policymakers, immunization program heads, and vaccine technical committee leads. Participants were identified by their 'elite' status among decisionmakers in the Indian vaccination space. Schutz' Social Phenomenological Theory guided development of an a priori framework derived from the Social Ecological Model. The framework helped organize participants' conceptualizations of communities, community engagement, and related themes. Inter-rater reliability was computed for a subsample of coded interviews, and findings were validated in a one-day member check-in meeting with study participants and teams. Results The interviews successfully elucidated participants' understanding of key terminology ("community") and approaches to community engagement propagated by the vaccine decision makers. Participants conceptualized 'communities' as vaccine-eligible children, their parents, frontline healthcare workers, and vaccination influencers. Engagement with those communities was understood to mean vaccine outreach, capacity-building of healthcare workers, and information dissemination. However, participants indicated that there were neither explicit policy guidelines defining community engagement nor pertinent evaluation metrics, despite awareness that community engagement is complex and under-researched. Examples of different approaches to community engagement ranged from vaccine imposition to empowered community vaccination decision-making. Finally, participants proposed an operational definition of community engagement and discussed concerns related to implementing it. Conclusions Although decision makers had different perceptions about what constitutes a community, and how community engagement should optimally function, the combined group articulated its importance to ensure vaccination equity and reiterated the need for concerted political will to build trust with communities. At the same time, work remains to be done both in terms of research on community engagement as well as development of appropriate implementation and outcome metrics.
    • A Qualitative Study Describing Nurses' Experiences With Presenteeism

      Rainbow, Jessica G; Dudding, Katherine M; Bethel, Claire; College of Nursing, University of Arizona (Lippincott Williams and Wilkins, 31-03-20)
      OBJECTIVE: The aim of this study was to understand nurse awareness of coping and decision making regarding presenteeism and the consequences thereof. BACKGROUND: Nurses report high levels of presenteeism or not being able to fully function in the workplace, but we currently lack understanding of nurse perceptions of presenteeism and its consequences. METHODS: A qualitative descriptive method was used to evaluate the perceptions of nurses from medical surgical units at 2 different hospitals. FINDINGS: For purposes of the study, presenteeism was defined as being present at work when not fully engaged. Most respondents experienced presenteeism in the month before data collection. Five categories of themes were identified: 1) factors leading to presenteeism, 2) awareness and symptoms of presenteeism, 3) coping with presenteeism on and off shift, 4) decision making regarding presenteeism, and 5) consequences of presenteeism. CONCLUSIONS: Both personal and work factors contribute to presenteeism. To decrease presenteeism, healthcare leaders and systems should consider reviewing and changing sick/leave polices, unit cultures, and a lack of resources that contribute to and encourage an awareness of presenteeism, thereby decreasing nurse fatigue. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.
    • A qualitative study of changes in expectations over time among patients with chronic low back pain seeking four CAM therapies

      Eaves, Emery R.; Sherman, Karen J.; Ritenbaugh, Cheryl; Hsu, Clarissa; Nichter, Mark; Turner, Judith A.; Cherkin, Daniel C.; Group Health Research Institute; Department of Family and Community Medicine & School of Anthropology, University of Arizona; Department of Psychiatry & Behavioral Sciences and Department of Rehabilitation Medicine, University of Washington School of Medicine (BioMed Central Ltd, 2015)
      BACKGROUND: The relationship between patient expectations about a treatment and the treatment outcomes, particularly for Complementary and Alternative Medicine (CAM) therapies, is not well understood. Using qualitative data from a larger study to develop a valid expectancy questionnaire for use with participants starting new CAM therapies, we examined how participants' expectations of treatment changed over the course of a therapy. METHODS: We conducted semi-structured qualitative interviews with 64 participants initiating one of four CAM therapies (yoga, chiropractic, acupuncture, massage) for chronic low back pain. Participants just starting treatment were interviewed up to three times over a period of 3 months. Interviews were transcribed verbatim and analyzed using a qualitative mixed methods approach incorporating immersion/crystallization and matrix analysis for a decontexualization and recontextualization approach to understand changes in thematic emphasis over time. RESULTS: Pre-treatment expectations consisted of conjecture about whether or not the CAM therapy could relieve pain and improve participation in meaningful activities. Expectations tended to shift over the course of treatment to be more inclusive of broader lifestyle factors, the need for long-term pain management strategies and attention to long-term quality of life and wellness. Although a shift toward greater acceptance of chronic pain and the need for strategies to keep pain from flaring was observed across participants regardless of therapy, participants varied in their assessments of whether increased awareness of the need for ongoing self-care and maintenance strategies was considered a "positive outcome". Regardless of how participants evaluated the outcome of treatment, participants from all four therapies reported increased awareness, acceptance of the chronic nature of pain, and attention to the need to take responsibility for their own health. CONCLUSIONS: The shift in treatment expectations to greater acceptance of pain and the need for continued self-care suggests that future research should explore how CAM practitioners can capitalize on these shifts to encourage feelings of empowerment rather than disappointment surrounding realizations of the need for continued engagement with self-care.
    • Quality Improvement and Safety in US Pharmacy Schools

      McManus, Katherine; Metrejean, Christina; Schweitzer, Kali; Cooley, Janet; Warholak, Terri; Univ Arizona, Coll Pharm (AMER ASSOC COLL PHARMACY, 2019-11-01)
      Objective. To catalog the methods in which quality improvement (QI) and safety are taught in schools and colleges of pharmacy in the United States and showcase exemplar QI programs. Methods. This descriptive, multi-phase study included an online questionnaire, syllabi review, and phone interviews. The study was approved by the University of Arizona Institutional Review Board (IRB). One representative from each US pharmacy school accredited by the Accreditation Council for Pharmacy Education (ACPE) was invited to participate. Participants indicated the type of QI education their school provided via online questionnaire. Following questionnaire completion, syllabi were requested from the schools and phone interviews were scheduled with a school representative to obtain additional information. From the data, exemplars were chosen using a predetermined, evidenced-based rubric. Results. Of the 136 schools contacted, 56 (41.2%) completed the survey. Of the responding schools reporting their QI and safety offerings, 41 (73.2%) had a required session/module; 24 (42.9%) had a required course; 21 (37.5%) had an elective course; 21 (37.5%) had an introductory pharmacy practice experience (IPPE), advanced pharmacy practice experience (APPE), or internship; 17 (30.4%) had a required project; 17 (30.4%) had interprofessional education integrated into their course; 15 (26.8%) had an error laboratory; and 11 (19.6%) offered postgraduate training. Conclusion. Many of the responding US schools of pharmacy expose students to some aspect of QI and/or safety, most often via class session or module. The exemplar programs serve as examples of how QI can be further integrated into pharmacy curricula.
    • Quality of life and functional vision across pediatric eye conditions assessed using the PedEyeQ

      Leske, David A; Hatt, Sarah R; Wernimont, Suzanne M; Castañeda, Yolanda S; Cheng-Patel, Christina S; Liebermann, Laura; Birch, Eileen E; Holmes, Jonathan M; Department of Ophthalmology and Vision Science, University of Arizona (Elsevier Inc., 2021-02-16)
      Purpose: To evaluate eye-related quality of life (ER-QOL) and functional vision across a wide range of pediatric eye conditions, using the Pediatric Eye Questionnaires (PedEyeQ). Methods: A total of 1,037 children with an eye condition and 254 visually normal controls, across 0-4, 5-11, and 12-17 years age groups, completed the following questionnaires: Child PedEyeQ (Functional Vision, Bothered by Eyes/Vision, Social, Frustration/Worry domains), Proxy PedEyeQ (same domains plus Eye Care), and Parent PedEyeQ (Impact on Parent and Family, Worry about Child's Eye Condition, Worry about Child's Self-perception and Interactions, and Worry about Functional Vision domains). The primary eye condition was classified as amblyopia (n = 171), cataract (n = 99), cerebral visual impairment (CVI; n = 50), cornea (n = 20), eyelid (n = 35), glaucoma (n = 24), nystagmus (n = 57), orbital (n = 19), pupil/iris (n = 7), refractive error (n = 119), retina (n = 82), strabismus (n = 332), and uveitis (n = 22). Results: PedEyeQ domain scores (scaled 0-100) were significantly worse across eye conditions, compared with controls. Child PedEyeQ greatest differences were on the Bothered by Eyes/Vision domain (nystagmus 5-11 years, −26 points [95% CI, −39 to −12]; nystagmus 12-17 years, −45 [95% CI, −61 to −28]). Proxy PedEyeQ differences were greatest on Functional Vision (CVI 0-4 years, −45 [95% CI, −56 to −34]; CVI 5-11 years, −58 [95% CI, −72 to −43]; nystagmus 12-17 years, −50 [95% CI, −69 to −31]). Parent PedEyeQ differences were greatest on Worry about Child's Functional Vision (CVI 0-4 years, −64; 95% CI −77 to −50). Conclusions: The PedEyeQ detects reduced ER-QOL and functional vision across pediatric eye conditions, and across age groups, indicating its utility for clinical practice and clinical trials. © 2021 American Association for Pediatric Ophthalmology and Strabismus
    • The Quality of Recovery after Dexamethasone, Ondansetron, or Placebo Administration in Patients Undergoing Lower Limbs Orthopedic Surgery under Spinal Anesthesia Using Intrathecal Morphine. A Randomized Controlled Trial

      Moro, Eduardo Toshiyuki; Ferreira, Miguel Antônio Teixeira; Gonçalves, Renyer Dos Santos; Vargas, Roberta Costa; Calil, Samira Joverno; Soranz, Maria Alice; Bloomstone, Joshua; Univ Arizona, Coll Med (HINDAWI LTD, 2020-05-20)
      Intrathecal morphine is widely and successfully used to prevent postoperative pain after orthopedic surgery, but it is frequently associated with side effects. The aim of this study was to evaluate the effect of dexamethasone or ondansetron when compared to placebo to reduce the occurrence of these undesirable effects and, consequently, to improve the quality of recovery based on patient's perspective. Methods. One hundred and thirty-five patients undergoing lower extremity orthopedic surgery under spinal anesthesia using bupivacaine and morphine were randomly assigned to receive IV dexamethasone, ondansetron, or saline. On the morning following surgery, a quality of recovery questionnaire (QoR-40) was completed. Results. No differences were detected in the global and dimensional QoR-40 scores following surgery; however, following postanesthesia care unit (PACU) discharge, pain scores were higher in patients receiving ondansetron compared with patients who received dexamethasone. Conclusion. Neither ondansetron nor dexamethasone improves the quality of recovery after lower limbs orthopedic surgery under spinal anesthesia using intrathecal morphine.
    • Quality standards, implementation autonomy, and citizen satisfaction with public services: cross-national evidence

      Song, Miyeon; An, Seung-Ho; Meier, Kenneth J.; Univ Arizona, Sch Govt (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2020-02-27)
      This article investigates whether citizens' evaluations of service performance are related to archival measures of performance, and how institutional context shapes this relationship contingent on administrative autonomy - standards, human resources, and financial autonomy. Using cross-national education data, this study finds that student performance is positively associated with parental evaluations of schools. Perceptions are more closely aligned with performance when agencies have greater autonomy in managing employees, and when national-level bureaucracies set performance standards. This research advances our understanding of the role of administrative autonomy in citizen satisfaction and provides implications for the institutional designs that can benefit performance assessment.
    • Quantal Risk Assessment Database: A Database for Exploring Patterns in Quantal Dose-Response Data in Risk Assessment and its Application to Develop Priors for Bayesian Dose-Response Analysis

      Wheeler, Matthew W; Piegorsch, Walter W; Bailer, Albert John; Univ Arizona, Interdisciplinary Program Stat (WILEY, 2019-03-01)
      Quantitative risk assessments for physical, chemical, biological, occupational, or environmental agents rely on scientific studies to support their conclusions. These studies often include relatively few observations, and, as a result, models used to characterize the risk may include large amounts of uncertainty. The motivation, development, and assessment of new methods for risk assessment is facilitated by the availability of a set of experimental studies that span a range of dose-response patterns that are observed in practice. We describe construction of such a historical database focusing on quantal data in chemical risk assessment, and we employ this database to develop priors in Bayesian analyses. The database is assembled from a variety of existing toxicological data sources and contains 733 separate quantal dose-response data sets. As an illustration of the database's use, prior distributions for individual model parameters in Bayesian dose-response analysis are constructed. Results indicate that including prior information based on curated historical data in quantitative risk assessments may help stabilize eventual point estimates, producing dose-response functions that are more stable and precisely estimated. These in turn produce potency estimates that share the same benefit. We are confident that quantitative risk analysts will find many other applications and issues to explore using this database.
    • Quantification of corrections for the main lunisolar nutation components and analysis of the free core nutation from VLBI-observed nutation residuals

      Zhu, Ping; Triana, Santiago Andrés; Rekier, Jerémy; Trinh, Antony; Dehant, Véronique; Lunar and Planetary Laboratory, University of Arizona (Springer Science and Business Media LLC, 2021-04-23)
      The attempt to quantify the corrections of lunisolar nutation components was made after analysis of six sets of Earth’s orientation parameters (EOP). The deviations of the long-term nutation components about IAU2006/IAU2000A precession–nutation model are consistent with the uncertainties suggested by Mathews et al. (J Geophys Res Solid Earth, 2002., but they exceed the errors determined in this work. The corrections are validated using the IERS 14C04 and IVS 19q4e combined solutions. After applying the corrections found in this work to the 14C04 nutation residuals, we analyzed the remaining signals, which contain the signature of the free core nutation (FCN). The eigenperiod of the FCN is fixed to the value derived from the resonance of the non-hydrostatic earth model in a priori. The amplitude of FCN is computed by fitting observations to the empirical model using a sliding window, the length of window is determined by taking into account the interference between those close nutation components and the FCN. In addition, we also fitted the nutation residuals by a viscous damping function; both methods produce the same results in the amplitudes of FCN. The magnitude of the free core nutation bears a “V-shape” distribution, and furthermore, the oscillation of the FCN shows a decay and a steady reinforcement before and after 1999. In order to examine the origin of the modulation in FCN’s magnitude, we briefly analyzed the possible damping or beating mechanism behind it. We diagnosed the magnitude and running phase changes of FCN by comparing it with the occurrence of the transient geomagnetic jerks. The weighted root mean square errors of nutation residuals are minimally reduced about 36 % when the corrections to the 21 nutation components and the FCN signature are considered together.
    • Quantification of Elemental Contaminants in Unregulated Water across Western Navajo Nation

      Credo, Jonathan; Torkelson, Jaclyn; Rock, Tommy; Ingram, Jani C; Univ Arizona, Coll Med, Clin Translat Sci Grad Program (MDPI, 2019-07-31)
      The geologic profile of the western United States lends itself to naturally elevated levels of arsenic and uranium in groundwater and can be exacerbated by mining enterprises. The Navajo Nation, located in the American Southwest, is the largest contiguous Native American Nation and has over a 100-year legacy of hard rock mining. This study has two objectives, quantify the arsenic and uranium concentrations in water systems in the Arizona and Utah side of the Navajo Nation compared to the New Mexico side and to determine if there are other elements of concern. Between 2014 and 2017, 294 water samples were collected across the Arizona and Utah side of the Navajo Nation and analyzed for 21 elements. Of these, 14 elements had at least one instance of a concentration greater than a national regulatory limit, and six of these (V, Ca, As, Mn, Li, and U) had the highest incidence of exceedances and were of concern to various communities on the Navajo Nation. Our findings are similar to other studies conducted in Arizona and on the Navajo Nation and demonstrate that other elements may be a concern for public health beyond arsenic and uranium.
    • Quantification of microplastics in north-western mediterranean harbors: Seasonality and biofilm-related metallic contaminants

      Onrubia, J.A.T.; Djaoudi, K.; Borgogno, F.; Canuto, S.; Angeletti, B.; Besio, G.; Capello, M.; Cutroneo, L.; Stocchino, A.; Mounier, S.; et al. (MDPI AG, 2021)
      The Mediterranean Sea is one of the most impacted basins in terms of microplastics pollution. Land-based activities are the major sources of plastic litter to the ocean, with harbors probably representing significant hotspots. In the framework of the SPlasH! project (Stop alle Plastiche in H2O, Interreg Marittimo project), microplastics were sampled in three north-western Mediterranean harbors during summer and winter. In this study, the areal concentrations of microplastics ranged from 5576 to 379,965 items·km−2 . A decreasing gradient was observed from the inner to the outer zones of the studied harbors, pointing out these enclosed systems as hotspots regarding microplastic pollution. During summer, the areal concentrations of microplastics were higher than in winter, which could be explained by an enhancement of port activities leading to MPs production. The investigation of microplastics size classes distribution in the surface waters revealed that microplastics within the size range between 300 µm and 500 µm were the least represented. In this study, we assessed trace metal (Pb, Fe, Cu, V, Cd and As) bioaccumulation by the biofilm which developed on the surface of microplastics. The results highlighted that concentrations within the biofilm were higher than those in the surrounding waters. This result strongly suggested trace metal bioaccumulation on microplastics through biofilm formation. When trace metal concentrations were normalized over the corresponding surface of microplastics and macroplastics, higher values were obtained for microplastics, evidencing their enhanced capacities to bioaccumulate contaminants when compared to macroplastics. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
    • Quantification of multiphoton and fluorescence images of reproductive tissues from a mouse ovarian cancer model shows promise for early disease detection

      Sawyer, Travis W; Koevary, Jennifer W; Rice, Faith P S; Howard, Caitlin C; Austin, Olivia J; Connolly, Denise C; Cai, Kathy Q; Barton, Jennifer K; Univ Arizona, Dept Biomed Engn; Univ Arizona, Coll Opt Sci (SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS, 2019-09-30)
      Ovarian cancer is the deadliest gynecologic cancer due predominantly to late diagnosis. Early detection of ovarian cancer can increase 5-year survival rates from 40% up to 92%, yet no reliable early detection techniques exist. Multiphoton microscopy (MPM) is a relatively new imaging technique sensitive to endogenous fluorophores, which has tremendous potential for clinical diagnosis, though it is limited in its application to the ovaries. Wide-field fluorescence imaging (WFI) has been proposed as a complementary technique to MPM, as it offers high-resolution imagery of the entire organ and can be tailored to target specific biomarkers that are not captured by MPM imaging. We applied texture analysis to MPM images of a mouse model of ovarian cancer. We also conducted WFI targeting the folate receptor and matrix metalloproteinases. We find that texture analysis of MPM images of the ovary can differentiate between genotypes, which is a proxy for disease, with high statistical significance (p < 0.001). The wide-field fluorescence signal also changes significantly between genotypes (p < 0.01). We use the features to classify multiple tissue groups to over 80% accuracy. These results suggest that MPM and WFI are promising techniques for the early detection of ovarian cancer. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.
    • Quantification of rock mass weathering using spectral imaging

      Park, J.; Kim, K.; Univ Arizona, Dept Min & Geol Engn (SOUTHERN AFRICAN INST MINING METALLURGY, 2019-12)
      The degree of weathering, a key parameter for evaluating rock mass strength, has traditionally been assessed based on visual inspection by engineers. In an effort to reduce the human bias associated with this approach, a study was conducted to investigate the potential for using spectral imaging to quantify weathering. This entailed developing a portable, rapid method for narrow-band multispectral (NBMS) remote sensing using a spectral index classification algorithm, applying this algorithm to detect weathered features, and then quantifying the degree of weathering based on the percentages of weathered and aperture areas. A case study was conducted on Mt. Lemmon in southern Arizona and spectral images were collected from rock slopes using a visible and near-infrared (VNIR) hyperspectral camera. A two-band ratio approach was used to delineate key areas. Wavelength ratios of 601 nm to 550 nm and 993 nm to 450 nm, were used to delineate weathered and aperture areas respectively on the rock mass. The weathering degree at the test site was then quantified using thematic images. This entailed assessing the percentages of the weathered (22.5%) and aperture (12.5%) areas in the thematic image and using them in a modified Geological Strength Index (GSI) evaluation. The weathering rating (R) was classified as 'slight' and scored as '5' based on the percentage of weathered and aperture areas, and the GSI was determined to be 43. This study successfully demonstrated the potential for using spectral information to quantify rock mass weathering, as well as for using the calculated weathering degree to How to cite: estimate the GSI.
    • Quantification of rock mass weathering using spectral imaging

      Park, J.; Kim, K.; Department of Mining and Geological Engineering, University of Arizona (South African Institute of Mining and Metallurgy, 2020)
      The degree of weathering, a key parameter for evaluating rock mass strength, has traditionally been assessed based on visual inspection by engineers. In an effort to reduce the human bias associated with this approach, a study was conducted to investigate the potential for using spectral imaging to quantify weathering. This entailed developing a portable, rapid method for narrow-band multispectral (NBMS) remote sensing using a spectral index classification algorithm, applying this algorithm to detect weathered features, and then quantifying the degree of weathering based on the percentages of weathered and aperture areas. A case study was conducted on Mt. Lemmon in southern Arizona and spectral images were collected from rock slopes using a visible and near-infrared (VNIR) hyperspectral camera. A two-band ratio approach was used to delineate key areas. Wavelength ratios of 601 nm to 550 nm and 993 nm to 450 nm, were used to delineate weathered and aperture areas respectively on the rock mass. The weathering degree at the test site was then quantified using thematic images. This entailed assessing the percentages of the weathered (22.5%) and aperture (12.5%) areas in the thematic image and using them in a modified Geological Strength Index (GSI) evaluation. The weathering rating (Rw) was classified as ‘slight’ and scored as ‘5’ based on the percentage of weathered and aperture areas, and the GSI was determined to be 43. This study successfully demonstrated the potential for using spectral information to quantify rock mass weathering, as well as for using the calculated weathering degree to estimate the GSI. © 2020 South African Institute of Mining and Metallurgy. All rights reserved.
    • Quantifying Adoption Intensity for Weed-Resistance Management Practices and Its Determinants among US Soybean, Corn, and Cotton Farmers

      Dong, Fengxia; Mitchell, Paul D.; Hurley, Terrance M.; Frisvold, George B.; Univ Arizona, Dept Agr & Resource Econ (WESTERN AGRICULTURAL ECONOMICS ASSOC, 2016-01)
      Using data envelopment analysis with principal components, we calculate an adoption-intensity index for herbicide-resistance best management practices (BMPs). Empirical results for over 1,100 farmers in twenty-two U.S. states suggest that many farmers could improve their herbicide resistance BMP adoption. Two-limit truncated regression results show that higher yields and a greater proportion of acres planted with Roundup Ready (R) seeds motivate weed BMP adoption. While soybean and corn farmers have lower adoption intensity than cotton farmers, farmer educational attainment and greater concern for herbicide effectiveness and for human and environmental safety are found to help increase the adoption of weed BMPs.
    • Quantifying and attributing time step sensitivities in present-day climate simulations conducted with EAMv1

      Wan, H.; Zhang, S.; Rasch, P.J.; Larson, V.E.; Zeng, X.; Yan, H.; Department of Hydrology and Atmospheric Sciences, University of Arizona (Copernicus GmbH, 2021)
      This study assesses the relative importance of time integration error in present-day climate simulations conducted with the atmosphere component of the Energy Exascale Earth System Model version 1 (EAMv1) at 1_ horizontal resolution. We show that a factor-of-6 reduction of time step size in all major parts of the model leads to significant changes in the long-term mean climate. Examples of changes in 10-year mean zonal averages include the following: 1. up to 0.5K of warming in the lower troposphere and cooling in the tropical and subtropical upper troposphere, 2. 1 %-10% decreases in relative humidity throughout the troposphere, and 3. 10 %-20% decreases in cloud fraction in the upper troposphere and decreases exceeding 20% in the subtropical lower troposphere. In terms of the 10-year mean geographical distribution, systematic decreases of 20 %-50% are seen in total cloud cover and cloud radiative effects in the subtropics. These changes imply that the reduction of temporal truncation errors leads to a notable although unsurprising degradation of agreement between the simulated and observed present-day climate; to regain optimal climate fidelity in the absence of those truncation errors, the model would require retuning.A coarsegrained attribution of the time step sensitivities is carried out by shortening time steps used in various components of EAM or by revising the numerical coupling between some processes. Our analysis leads to the finding that the marked decreases in the subtropical low-cloud fraction and total cloud radiative effect are caused not by the step size used for the collectively subcycled turbulence, shallow convection, and stratiform cloud macrophysics and microphysics parameterizations but rather by the step sizes used outside those subcycles. Further analysis suggests that the coupling frequency between the subcycles and the rest of EAM significantly affects the subtropical marine stratocumulus decks, while deep convection has significant impacts on trade cumulus. The step size of the cloud macrophysics and microphysics subcycle itself appears to have a primary impact on cloud fraction in the upper troposphere and also in the midlatitude near-surface layers. Impacts of step sizes used by the dynamical core and the radiation parameterization appear to be relatively small. These results provide useful clues for future studies aiming at understanding and addressing the root causes of sensitivities to time step sizes and process coupling frequencies in EAM. While this study focuses on EAMv1 and the conclusions are likely model-specific, the presented experimentation strategy has general value for weather and climate model development, as the methodology can help researchers identify and understand sources of time integration error in sophisticated multi-component models. © Author(s) 2021.