Now showing items 21-40 of 100168

    • Learning Open Domain Multi-hop Search Using Reinforcement Learning

      Noriega-Atala, E.; Surdeanu, M.; Morrison, C.T.; University of Arizona (Association for Computational Linguistics (ACL), 2022)
      We propose a method to teach an automated agent to learn how to search for multi-hop paths of relations between entities in an open domain. The method learns a policy for directing existing information retrieval and machine reading resources to focus on relevant regions of a corpus. The approach formulates the learning problem as a Markov decision process with a state representation that encodes the dynamics of the search process and a reward structure that minimizes the number of documents that must be processed while still finding multi-hop paths. We implement the method in an actor-critic reinforcement learning algorithm and evaluate it on a dataset of search problems derived from a subset of English Wikipedia. The algorithm finds a family of policies that succeeds in extracting the desired information while processing fewer documents compared to several baseline heuristic algorithms. © 2022 Association for Computational Linguistics.
    • A Systematic Survey of Text Worlds as Embodied Natural Language Environments

      Jansen, P.A.; University of Arizona (Association for Computational Linguistics (ACL), 2022)
      Text Worlds are virtual environments for embodied agents that, unlike 2D or 3D environments, are rendered exclusively using textual descriptions. These environments offer an alternative to higher-fidelity 3D environments due to their low barrier to entry, providing the ability to study semantics, compositional inference, and other high-level tasks with rich action spaces while controlling for perceptual input. This systematic survey outlines recent developments in tooling, environments, and agent modeling for Text Worlds, while examining recent trends in knowledge graphs, common sense reasoning, transfer learning of Text World performance to higher-fidelity environments, as well as near-term development targets that, once achieved, make Text Worlds an attractive general research paradigm for natural language processing. © 2022 Association for Computational Linguistics.
    • Entangled Sensor-Networks for Dark-Matter Searches

      Brady, A.J.; Gao, C.; Harnik, R.; Liu, Z.; Zhang, Z.; Zhuang, Q.; Department of Electrical and Computer Engineering, University of Arizona; Department of Materials Science and Engineering, University of Arizona; Wyant College of Optical Sciences, University of Arizona (American Physical Society, 2022)
      The hypothetical axion particle (of unknown mass) is a leading candidate for dark matter (DM). Many experiments search for axions with microwave cavities, where an axion may convert into a cavity photon, leading to a feeble excess in the output power of the cavity. Recent work [Backes et al., Nature 590, 238 (2021)] has demonstrated that injecting squeezed vacuum into the cavity can substantially accelerate the axion search. Here, we go beyond and provide a theoretical framework to leverage the benefits of quantum squeezing in a network setting consisting of many sensor cavities. By forming a local sensor network, the signals among the cavities can be combined coherently to boost the axion search. Furthermore, injecting multipartite entanglement across the cavities - generated by splitting a squeezed vacuum - enables a global noise reduction. We explore the performance advantage of such a local, entangled sensor network, which enjoys both coherence between the axion signals and entanglement between the sensors. Our analyses are pertinent to next-generation DM-axion searches aiming to leverage a network of sensors and quantum resources in an optimal way. Finally, we assess the possibility of using a more exotic quantum state, the Gottesman-Kitaev-Preskill (GKP) state. Despite a constant-factor improvement in the scan time relative to a single-mode squeezed state in the ideal case, the advantage of employing a GKP state disappears when a practical measurement scheme is considered. © 2022 authors. Published by the American Physical Society.
    • SemEval-2021 Task 10: Source-Free Domain Adaptation for Semantic Processing

      Laparra, E.; Su, X.; Zhao, Y.; Uzuner, Ö.; Miller, T.A.; Bethard, S.; University of Arizona (Association for Computational Linguistics (ACL), 2021)
      This paper presents the Source-Free Domain Adaptation shared task held within SemEval-2021. The aim of the task was to explore adaptation of machine-learning models in the face of data sharing constraints. Specifically, we consider the scenario where annotations exist for a domain but cannot be shared. Instead, participants are provided with models trained on that (source) data. Participants also receive some labeled data from a new (development) domain on which to explore domain adaptation algorithms. Participants are then tested on data representing a new (target) domain. We explored this scenario with two different semantic tasks: negation detection (a text classification task) and time expression recognition (a sequence tagging task). © 2021 Association for Computational Linguistics.
    • Vagal control moderates the association between endothelial function and PTSD symptoms in women with T2DM

      Seligowski, A.V.; Fonkoue, I.T.; Noble, N.C.; Dixon, D.; Gluck, R.; Kim, Y.J.; Powers, A.; Pace, T.W.W.; Jovanovic, T.; Umpierrez, G.; et al. (Elsevier Inc., 2022)
      Background: Individuals with posttraumatic stress disorder (PTSD) are more likely to present with metabolic diseases such as type-2 diabetes mellitus (T2DM), and cardiovascular dysfunction has been implicated in this link. These diseases disproportionately affect women and individuals exposed to chronic environmental stressors (e.g., community violence, poverty). We examined associations among PTSD, cardiovascular indices, and metabolic function in highly trauma-exposed Black women with T2DM. Methods: Participants (N = 80) were recruited for a follow-up study of stress and T2DM as part of the Grady Trauma Project. PTSD symptoms were assessed with the Clinician Administered PTSD Scale (CAPS-IV). Cardiovascular indices included heart rate (HR), blood pressure (BP), respiratory sinus arrhythmia (RSA), and endothelial function (assessed via flow-mediated dilation; FMD). An oral glucose tolerance test was used as an indicator of metabolic function. Results: Of the cardiovascular indices, only FMD was significantly associated with PTSD symptoms (CAPS Avoidance symptoms; β = −0.37, p = .042), and glucose tolerance (β = −0.44, p = .019), controlling for age and body mass index. The association between FMD and PTSD Avoidance was moderated by RSA such that the effect of FMD was only significant at low levels of RSA (simple slopes β = −0.87, p = .004). Conclusions: Our results indicate that endothelial function is significantly related to PTSD and glucose tolerance, over and above other cardiovascular measures (HR, BP, RSA). Further, our results suggest that low RSA may be a risk factor for the link between poor endothelial function and PTSD in women with T2DM. © 2022 The Authors
    • The ESA Hera Mission: Detailed Characterization of the DART Impact Outcome and of the Binary Asteroid (65803) Didymos

      Michel, P.; Küppers, M.; Bagatin, A.C.; Carry, B.; Charnoz, S.; de Leon, J.; Fitzsimmons, A.; Gordo, P.; Green, S.F.; Hérique, A.; et al. (Institute of Physics, 2022)
      Hera is a planetary defense mission under development in the Space Safety and Security Program of the European Space Agency for launch in 2024 October. It will rendezvous in late 2026 December with the binary asteroid (65803) Didymos and in particular its moon, Dimorphos, which will be impacted by NASA’s DART spacecraft on 2022 September 26 as the first asteroid deflection test. The main goals of Hera are the detailed characterization of the physical properties of Didymos and Dimorphos and of the crater made by the DART mission, as well as measurement of the momentum transfer efficiency resulting from DART’s impact. The data from the Hera spacecraft and its two CubeSats will also provide significant insights into asteroid science and the evolutionary history of our solar system. Hera will perform the first rendezvous with a binary asteroid and provide new measurements, such as radar sounding of an asteroid interior, which will allow models in planetary science to be tested. Hera will thus provide a crucial element in the global effort to avert future asteroid impacts at the same time as providing world-leading science. © 2022. The Author(s). Published by the American Astronomical Society.
    • A solution to the challenges of interdisciplinary aggregation and use of specimen-level trait data

      Balk, M.A.; Deck, J.; Emery, K.F.; Walls, R.L.; Reuter, D.; LaFrance, R.; Arroyo-Cabrales, J.; Barrett, P.; Blois, J.; Boileau, A.; et al. (Elsevier Inc., 2022)
      Understanding variation of traits within and among species through time and across space is central to many questions in biology. Many resources assemble species-level trait data, but the data and metadata underlying those trait measurements are often not reported. Here, we introduce FuTRES (Functional Trait Resource for Environmental Studies; pronounced few-tress), an online datastore and community resource for individual-level trait reporting that utilizes a semantic framework. FuTRES already stores millions of trait measurements for paleobiological, zooarchaeological, and modern specimens, with a current focus on mammals. We compare dynamically derived extant mammal species' body size measurements in FuTRES with summary values from other compilations, highlighting potential issues with simply reporting a single mean estimate. We then show that individual-level data improve estimates of body mass—including uncertainty—for zooarchaeological specimens. FuTRES facilitates trait data integration and discoverability, accelerating new research agendas, especially scaling from intra- to interspecific trait variability. © 2022 The Authors
    • Temporal evaluation of efficacy and quality of tissue repair upon laser-activated sealing

      Ghosh, D.; Salinas, C.M.; Pallod, S.; Roberts, J.; Makin, I.R.S.; Yaron, J.R.; Witte, R.S.; Rege, K.; James C. Wyant College of Optical Sciences, University of Arizona; Department of Medical Imaging, University of Arizona (John Wiley and Sons Inc, 2022)
      Injuries caused by surgical incisions or traumatic lacerations compromise the structural and functional integrity of skin. Immediate approximation and robust repair of skin are critical to minimize occurrences of dehiscence and infection that can lead to impaired healing and further complication. Light-activated skin sealing has emerged as an alternative to sutures, staples, and superficial adhesives, which do not integrate with tissues and are prone to scarring and infection. Here, we evaluate both shorter- and longer-term efficacy of tissue repair response following laser-activated sealing of full-thickness skin incisions in immunocompetent mice and compare them to the efficacy seen with sutures. Laser-activated sealants (LASEs) in which, indocyanine green was embedded within silk fibroin films, were used to form viscous pastes and applied over wound edges. A hand-held, near-infrared laser was applied over the incision, and conversion of the light energy to heat by the LASE facilitated rapid photothermal sealing of the wound in approximately 1 min. Tissue repair with LASEs was evaluated using functional recovery (transepidermal water loss), biomechanical recovery (tensile strength), tissue visualization (ultrasound [US] and photoacoustic imaging [PAI]), and histology, and compared with that seen in sutures. Our studies indicate that LASEs promoted earlier recovery of barrier and mechanical function of healed skin compared to suture-closed incisions. Visualization of sealed skin using US and PAI indicated integration of the LASE with the tissue. Histological analyses of LASE-sealed skin sections showed reduced neutrophil and increased proresolution macrophages on Days 2 and 7 postclosure of incisions, without an increase in scarring or fibrosis. Together, our studies show that simple fabrication and application methods combined with rapid sealing of wound edges with improved histological outcomes make LASE a promising alternative for management of incisional wounds and lacerations. © 2022 The Authors. Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.
    • mHealth-Supported Gender- and Culturally Sensitive Weight Loss Intervention for Hispanic Men With Overweight and Obesity: Single-Arm Pilot Study

      Garcia, D.O.; Valdez, L.A.; Aceves, B.; Bell, M.L.; Rabe, B.A.; Villavicencio, E.A.; Marrero, D.G.; Melton, F.; Hooker, S.P.; Department of Health Promotion Sciences, Mel and Enid Zuckerman College of Public Health, University of Arizona; et al. (JMIR Publications Inc., 2022)
      Background: Hispanic men have disproportionate rates of overweight and obesity compared with other racial and ethnic subpopulations. However, few weight loss interventions have been developed specifically for this high-risk group. Furthermore, the use of mobile health (mHealth) technologies to support lifestyle behavior changes in weight loss interventions for Hispanic men is largely untested. Objective: This single-arm pilot study examined the feasibility and acceptability of integrating mHealth technology into a 12-week gender- and culturally sensitive weight loss intervention (GCSWLI) for Hispanic men with overweight and obesity. Methods: A total of 18 Hispanic men (mean age 38, SD 10.9 years; mean BMI 34.3, SD 5.5 kg/m2; 10/18, 56% Spanish monolingual) received a GCSWLI, including weekly in-person individual sessions, a daily calorie goal, and prescription of ≥225 minutes of moderate-intensity physical activity per week. mHealth technology support included tailored SMS text messaging, behavior self-monitoring support using Fitbit Charge 2, and weight tracking using a Fitbit Aria Wi-Fi Smart Scale. Changes in weight from baseline to 12 weeks were estimated using a paired 2-tailed t test. Descriptive analyses characterized the use of Fitbit and smart scales. Semistructured interviews were conducted immediately after intervention to assess the participants’ weight loss experiences and perspectives on mHealth technologies. Results: Of 18 participants, 16 (89%) completed the 12-week assessments; the overall attrition rate was 11.1%. The mean weight loss at week 12 was −4.7 kg (95% CI 7.1 to −2.4 kg; P<.001). Participants wore the Fitbit 71.58% (962/1344) of the intervention days and logged their body weight using the smart scale (410/1344, 30.51% of the intervention days). Participants identified barriers to the use of the technology, such as lack of technological literacy and unreliable internet access for the smart scale. Conclusions: Although clinically significant weight loss was achieved by integrating mHealth technology into the GCSWLI, adherence to the prescribed use of technology was modest. Addressing barriers to the use of such technologies identified in our work may help to refine an mHealth intervention approach for Hispanic men. ©David O Garcia, Luis A Valdez, Benjamin Aceves, Melanie L Bell, Brooke A Rabe, Edgar A Villavicencio, David G Marrero, Forest Melton, Steven P Hooker.
    • First peripheral drug-eluting stent clinical results from China: 1-year outcomes of the Zilver PTX China study

      Ye, W.; Böhme, T.; Fu, W.; Liu, C.; Zhang, X.; Liu, P.; Zhang, J.; Zou, Y.; Lu, X.; Lottes, A.E.; et al. (Frontiers Media S.A., 2022)
      Purpose: The benefit of using the Zilver PTX drug-eluting stent (DES) in superficial femoral artery (SFA) lesions has been demonstrated in multiple clinical studies. This prospective, multicenter study evaluated the 1-year safety and effectiveness of the DES for the treatment of femoropopliteal lesions in a Chinese patient population. Methods: Patients with a single de novo or restenotic SFA lesion ≤140 mm and a Rutherford classification of 2 to 4 were treated with the DES. The primary endpoint was primary patency assessed by duplex ultrasound at 1-year. Secondary endpoints included adverse events, event-free survival (EFS), and freedom from target lesion revascularization (TLR). Clinical outcomes included Rutherford classification, ankle-brachial index (ABI), and the walking impairment questionnaire (WIQ). Results: In this study, 178 patients with symptomatic peripheral artery disease were enrolled at nine institutions in China. The average lesion length was 79.0 ± 48.6 mm (range 14.8–245.4 mm) and 50.0% of lesions were total occlusions. The 1-year primary patency rate was 81.9%. Covariate analysis revealed that lesion length (p < 0.01) was the only significant factor for patency. No paclitaxel-related adverse events or amputations were reported. The 1-year rate for EFS was 94.9% and freedom from TLR was 95.5%. Through 1-year, treatment with the DES resulted in statistically significant improvement in ABI and WIQ scores compared with pre-procedure (p < 0.001). Clinical improvement of at least 1 Rutherford class was achieved in 142 of 174 patients (81.6%). Conclusion: This study showed promising short-term results for the treatment of SFA lesions with Zilver PTX DES in Chinese patients. Unique identifier: ClinicalTrials.gov, identifier: NCT02171962. Copyright © 2022 Ye, Böhme, Fu, Liu, Zhang, Liu, Zhang, Zou, Lu, Lottes, O'Leary, Zeller and Dake.
    • Professional-Collector Collaboration: Global Challenges and Solutions

      Thomas, S.; Wessman, A.; Pitblado, B.L.; Rowe, M.; Schroeder, B.; School of Anthropology, University of Arizona (Cambridge University Press, 2022)
      This introductory article foregrounds the articles in this special issue, Professional-Collector Collaboration: Global Challenges and Solutions, complementing the special issue Professional-Collector Collaboration Moving beyond Debate to Best Practice, also published in Advances in Archaeological Practice. The articles that we introduce here cover examples and case studies from European settings such as Norway, the Czech Republic, England, Wales, Finland, and Belgium - places that have been exploring how to respond to the challenge of working meaningfully with collectors and finders of archaeological artifacts, especially metal detectorists. These are joined by examples from Australia, Mexico, Uruguay, and even the United States, in the context of handling - at first glance - problematic collections originating from elsewhere. The articles are diverse in their settings and the challenges they describe, but they point to the need for participatory and democratic approaches to archaeological heritage and the different publics that engage with it. Copyright © The Author(s), 2022. Published by Cambridge University Press on behalf of Society for American Archaeology.
    • Sedimentary records and chronology of the late Pleistocene overbank flooding in the Yellow River source area, NE Tibetan Plateau

      Zhu, Y.; Wang, H.; Zhang, Y.; Huang, C.C.; Zha, X.; Qiu, H.; Jia, Y.-N.; Xiao, Q.; Chen, D.; Lin, X.; et al. (Frontiers Media S.A., 2022)
      Paleohydrological investigations were carried out in the Yellow River source area on the northeast (NE) Tibetan Plateau. During our fieldwork investigations, two units of overbank flood deposits (OFD) were found in the Maqu-Kesheng reach. These OFD units were studied using a multi-index approach, including magnetic susceptibility, hygroscopic water, grain size distribution and micro-morphological features. It can be inferred that they have recorded two episodes of overbank flooding of the Yellow River. Using the optically stimulated luminescence (OSL) and AMS 14C dating techniques, the first episode was dated to 34,680 ± 1880-29000 ± 1790 a and correlated with the late Marine Isotope Stage 3a (MIS 3a) with a warm and wet climate. The second episode occurred at 16,500 ± 1,250-14000 ± 1,280 a, which is coincided with the Bølling-Allerød warm stage during the last deglaciation, a period of coexisting global warming and rapidly shrinking ice sheets. At these two periods, the water was mainly derived from the accelerated melting of mountain glaciers surrounding the basin and/or the large-scale precipitation, which led to the overbank flooding events. At the same time, the related overbank flood deposits were interbedded within glacial outwash/flashflood deposits in the valley bottom of the Yellow River, which intensified the valley aggradation. These results are of great significance in enriching the paleoflood records in the Yellow River source area, recognizing the effect of river system on the development of valley landform, as well as understanding the hydro-climatic response of the Tibetan Plateau to global climate warming occurring presently. Copyright © 2022 Zhu, Wang, Zhang, Huang, Zha, Qiu, Jia, Xiao, Chen, Lin and Liu.
    • Experimental constraints on the stability and oscillation of water vapor film—a precursor for phreatomagmatic and explosive submarine eruptions

      Sonder, I.; Moitra, P.; Department of Geosciences, University of Arizona (Frontiers Media S.A., 2022)
      Pre-mixing of magma and external water plays a key role in driving explosive phreatomagmatic and submarine volcanic eruptions. A thin film of water vapor forms at the magma–water interface as soon as hot magma comes in direct contact with the cold water (Leidenfrost effect). The presence of a stable vapor film drives efficient mixing and mingling between magma and water, as well as magma and wet and water-saturated sediments. Such mixing occurs before explosive molten fuel–coolant type interactions. Using high-temperature laboratory experiments, we investigate the effect of magma and water temperatures on the stability of vapor film, which has not been performed systematically for a magmatic heat source. The experiments were performed with re-melted volcanic rock material, from which spherically-shaped rock samples were produced. These samples were heated to 1,110°C and then submerged in a water pool with a constant temperature (3–93°C). The experiments were recorded on video, and, synchronously, sample and water temperatures were measured using thermocouples. The time-dependent thickness of the vapor film was measured from the video material. The vapor film tends to oscillate with time on the order of 102 Hz. We find that the vertical collapse rates of vapor films along the sample–water interfaces are 13.7 mm s−1 and 4.2 mm s−1 for water temperatures of 3.0°C and 65°C, respectively. For a given initial sample temperature, the thickness and stability time scales decrease with decreasing water temperature, which has implications for the efficiency of pre-mixing required for explosive eruptions. Using thermodynamics and previously measured material parameters, it is shown that a sudden collapse of the vapor film can start brittle fragmentation of the melt and thus serves as the starting point of thermohydraulic explosions. Copyright © 2022 Sonder and Moitra.
    • The Flp type IV pilus operon of Mycobacterium tuberculosis is expressed upon interaction with macrophages and alveolar epithelial cells

      Alteri, C.J.; Rios-Sarabia, N.; De la Cruz, M.A.; González-y-Merchand, J.A.; Soria-Bustos, J.; Maldonado-Bernal, C.; Cedillo, M.L.; Yáñez-Santos, J.A.; Martínez-Laguna, Y.; Torres, J.; et al. (Frontiers Media S.A., 2022)
      The genome of Mycobacterium tuberculosis (Mtb) harbors the genetic machinery for assembly of the Fimbrial low-molecular-weight protein (Flp) type IV pilus. Presumably, the Flp pilus is essential for pathogenesis. However, it remains unclear whether the pili genes are transcribed in culture or during infection of host cells. This study aimed to shed light on the expression of the Flp pili-assembly genes (tadZ, tadA, tadB, tadC, flp, tadE, and tadF) in Mtb growing under different growth conditions (exponential phase, stationary phase, and dormancy NRP1 and NRP2 phases induced by hypoxia), during biofilm formation, and in contact with macrophages and alveolar epithelial cells. We found that expression of tad/flp genes was significantly higher in the stationary phase than in exponential or NRP1 or NRP2 phases suggesting that the bacteria do not require type IV pili during dormancy. Elevated gene expression levels were recorded when the bacilli were in contact for 4 h with macrophages or epithelial cells, compared to mycobacteria propagated alone in the cultured medium. An antibody raised against a 12-mer peptide derived from the Flp pilin subunit detected the presence of Flp pili on intra- and extracellular bacteria infecting eukaryotic cells. Altogether, these are compelling data showing that the Flp pili genes are expressed during the interaction of Mtb with host cells and highlight a role for Flp pili in colonization and invasion of the host, subsequently promoting bacterial survival during dormancy. Copyright © 2022 Alteri, Rios-Sarabia, De la Cruz, González-y-Merchand, Soria-Bustos, Maldonado-Bernal, Cedillo, Yáñez-Santos, Martínez-Laguna, Torres, Friedman, Girón and Ares.
    • An integrated approach to panel width, fleet size, and change-out time optimization in room-and-pillar mines

      Anani, A.; Nyaaba, W.; Córdova, E.; Department of Mining and Geological Engineering, University of Arizon (South African Institute of Mining and Metallurgy, 2022)
      Optimization of panels, haulage fleet, and waiting area involves deterministic and low-fidelity methods and experiential knowledge. The process is challenging because coal recovery and operational capabilities must be considered in the solution. The approach in this manuscript comprises the development of an integrated stochastic simulation model of a coal room-and-pillar system that addresses these challenges. The decision variables evaluated are panel width, number of shuttle cars, and change-out time (COT). The results show that the mine should implement the shortest possible COT, decreasing the cycle time and thereby increasing productivity and continuous miner (CM) utilization. The highest productivity and CM utilization for a fleet size of three shuttle cars is found in the 15-entry panel width. For the evaluated fleet sizes, the 19-entry panel width is optimal for the four and five shuttle cars. Among the three variables studied, panel width and fleet size had the most significant effects (5% increase) on the CM productivity, cycle time, and utilization. © 2022 South African Institute of Mining and Metallurgy. All rights reserved.
    • Re-Training of Convolutional Neural Networks for Glottis Segmentation in Endoscopic High-Speed Videos

      Döllinger, M.; Schraut, T.; Henrich, L.A.; Chhetri, D.; Echternach, M.; Johnson, A.M.; Kunduk, M.; Maryn, Y.; Patel, R.R.; Samlan, R.; et al. (MDPI, 2022)
      Endoscopic high-speed video (HSV) systems for visualization and assessment of vocal fold dynamics in the larynx are diverse and technically advancing. To consider resulting “concepts shifts” for neural network (NN)-based image processing, re-training of already trained and used NNs is necessary to allow for sufficiently accurate image processing for new recording modalities. We propose and discuss several re-training approaches for convolutional neural networks (CNN) being used for HSV image segmentation. Our baseline CNN was trained on the BAGLS data set (58,750 images). The new BAGLS-RT data set consists of additional 21,050 images from previously unused HSV systems, light sources, and different spatial resolutions. Results showed that increasing data diversity by means of preprocessing already improves the segmentation accuracy (mIoU + 6.35%). Subsequent re-training further increases segmentation performance (mIoU + 2.81%). For re-training, finetuning with dynamic knowledge distillation showed the most promising results. Data variety for training and additional re-training is a helpful tool to boost HSV image segmentation quality. However, when performing re-training, the phenomenon of catastrophic forgetting should be kept in mind, i.e., adaption to new data while forgetting already learned knowledge. © 2022 by the authors.
    • Assessment of the Effects of COVID-19 Pandemic Stay-at-Home Measures on Potable Water Consumption Patterns, Location, and Financial Impacts for Water Utilities in Colombian Cities

      Ortiz, C.; Salcedo, C.; Saldarriaga, J.; Department of Civil and Architectural Engineering and Mechanics, University of Arizona (MDPI, 2022)
      Several studies suggest that social distancing measures due to the COVID-19 pandemic have affected the water sector, specifically regarding its demand and supply. Given the importance of hygiene practices, this effect is heightened by the role that potable water availability has in tackling the spread of the virus. This study aimed to assess the impact of the pandemic on the water consumption patterns and location in four Colombian cities known for their important commercial, industrial, academic, and touristic features. Results exhibit diverse diminishing water consumption trends alongside COVID-19 because of different attributes of the cities (e.g., size, environmental, socioeconomic, and sociocultural characteristics). For instance, the touristic case study has been the most affected because of travel restrictions, with an average commercial demand drop of 32%. In contrast, industrial case studies have had a rapid recovery in water demand, with average industrial drops of 11–14% compared to 20–25% in non-industrial cities. These water demand changes do not affect only the operation of water utilities, but also their finances. Economic losses were estimated at 3.7%, 2.4%, and 6.4% of the expected incomes for the first 14 months of the pandemic for the case studies in this paper. Under a changing environment, understanding these changes and challenges is fundamental for ensuring that water systems are resilient in any unexpected situation. © 2022 by the authors.
    • Ecohydrology of Green Stormwater Infrastructure in Shrinking Cities: A Two-Year Case Study of a Retrofitted Bioswale in Detroit, MI

      Papuga, S.A.; Seifert, E.; Kopeck, S.; Hwang, K.; Department of Hydrology and Atmospheric Science, University of Arizona (MDPI, 2022)
      Stormwater management is of great importance in large shrinking cities with aging and outdated infrastructure. Maintenance of vegetated areas, particularly referred to as green infrastructure, is often aimed at mitigating flooding and the urban heat island effect by stormwater storage and evaporative cooling, respectively. This approach has been applied in large cities as a cost-effective and eco-friendly solution. However, the ecohydrological processes and how the ecohydrology influences the function of green infrastructure and its potential to provide those ecosystem services are not well understood. In this study, continuous field measurements including air temperature, stomatal conductance, and phenocam images were taken in a 308 m2 bioswale retrofitted into a 4063 m2 parking lot on the Wayne State University campus in Detroit, Michigan over a two-year period. Our results suggest that plant characteristics such as water use efficiency impact the ecohydrological processes within bioswales and that retrofitted bioswales will need to be adapted over time to meet environmental demands to allow for full and sustained success. Therefore, projected shifts in precipitation regime change are expected to affect the performance of green infrastructure, and each bioswale needs to be developed and engineered to be able to adapt to changing rainfall patterns. © 2022 by the authors.
    • Prevalence and Outcomes of COVID-19 among Hematology/Oncology Patients and Providers of a Community-Facing Health System during the B1.1.529 (“Omicron”) SARS-CoV-2 Variant Wave

      Kareff, S.A.; Khan, A.; Barreto-Coelho, P.; Iyer, S.G.; Pico, B.; Stanchina, M.; Dutcher, G.; Monteiro de Oliveira Novaes, J.; Nallagangula, A.; Lopes, G.; et al. (MDPI, 2022)
      (1) Background: the SARS-CoV-2 (COVID-19) pandemic continues, and patients actively receiving chemotherapy are known to be at enhanced risk for developing symptomatic disease with poorer outcomes. Our study evaluated the prevalence of COVID-19 among patients and providers of our community-facing county health system during the B1.1.529 (“Omicron”) COVID-19 variant wave. (2) Methods: We retrospectively analyzed patients that received care and clinical providers whom worked at the Jackson Memorial Hospital Hematology/Oncology clinic in Miami, Florida, USA, from 1 December 2021 through 30 April 2022. We assessed demographic variables and quality outcomes among patients. (3) Results: 1031 patients and 18 providers were retrospectively analyzed. 90 patients tested positive for COVID-19 (8.73%), while 6 providers tested positive (33.3%) (p = 0.038). There were 4 (10.3%) COVID-19-related deaths (and another outside our study timeframe) and 39 non-COVID-19-related deaths (89.7%) in the patient population (p = 0.77). COVID-19 accounted for 4.44% of our clinic’s total mortality, and delayed care in 64.4% of patients. (4) Conclusions: The prevalence of COVID-19 positivity in our patient cohort mirrored local, state, and national trends, however a statistically significant greater proportion of our providers tested positive. Almost two-thirds of patients experienced a cancer treatment delay, significantly impacting oncologic care. © 2022 by the authors.
    • Understanding Intensity–Duration–Frequency (IDF) Curves Using IMERG Sub-Hourly Precipitation against Dense Gauge Networks

      Lau, A.; Behrangi, A.; Department of Hydrology and Atmospheric Sciences, University of Arizona (MDPI, 2022)
      The design storm derived from intensity–duration–frequency (IDF) curves is the main input for hydrologic analysis or hydraulic design for flood control. The regions with higher flood risks due to extreme precipitation are often deficient in precipitation gauges. This study presents a detailed evaluation of IDF curves derived using IMERG Final half-hourly precipitation (V06), fitted with the widely used CDFs: Gumbel and MLE, Gumbel and MM, Pearson 3, and GEV. As benchmarks and following the same method, we also derived IDF curves using areal average gridded precipitation constructed from two dense gauges networks over (1) the WegenerNET Feldbach region in the Alpine forelands of Austria and (2) the gauge network of the Walnut Gulch Experimental Watershed, in a semiarid region of the United States. In both regions, the frequency analysis for return periods between 2 and 100 years was based on half-hourly rainfall and compared at a grid-scale with a spatial resolution of IMERG, 0.1° × 0.1° lat/lon. The impact of order in which the gridded gauge-based precipitation average is performed within an IMERG grid was evaluated by computing two different Annual Maximum Series (AMS). In one, the average was computed before obtaining the AMS (AB-AMS), and in the other, the average was computed after obtaining the AMS for each gauge grid (AA-AMS) within the IMERG grid. The evaluation revealed that IMERG AMS agrees better with AB-AMS than AA-AMS for the two study regions. Lastly, it was found that the use of Gumbel distribution in calculating IMERG IDF curves results in better agreement with the ground truth than the use of the other three distributions studied here. The outcomes should provide valuable knowledge for the application of IMERG precipitation over regions with sparse gauges. © 2022 by the authors.