1,182 results on '"Lewis, Mark"'
Search Results
2. Some results on variations on the norm of finite groups: Variations on group norms: M.L. Lewis et al.
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Lewis, Mark L., Shen, Zhencai, and Yan, Quanfu
- Abstract
Let G be a finite group and N Ω (G) be the intersection of the normalizers of all subgroups belonging to the set Ω (G) , where Ω (G) is a set of all subgroups of G which have some theoretical group property. In this paper, we show that N Ω (G) = Z ∞ (G) if Ω (G) is one of the following: (i) the set of all self-normalizing subgroups of G; (ii) the set of all subgroups of G satisfying the subnormalizer condition in G; (iii) the set of all pronormal subgroups of G; (iv) the set of all weakly normal subgroups of G; (v) the set of all NE-subgroups of G. [ABSTRACT FROM AUTHOR] more...
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- 2025
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Catalog
3. The commuting graph of a solvable 퐴-group.
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Carleton, Rachel and Lewis, Mark L.
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SYLOW subgroups ,FINITE groups ,DIAMETER - Abstract
Let 퐺 be a finite group. Recall that an 퐴-group is a group whose Sylow subgroups are all abelian. In this paper, we investigate the upper bound on the diameter of the commuting graph of a solvable 퐴-group. Assuming that the commuting graph is connected, we show when the derived length of 퐺 is 2, the diameter of the commuting graph will be at most 4. In the general case, we show that the diameter of the commuting graph will be at most 6. In both cases, examples are provided to show that the upper bound of the commuting graph cannot be improved. [ABSTRACT FROM AUTHOR] more...
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- 2025
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4. Eruptive Insect Outbreaks from Endemic Populations Under Climate Change.
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Brush, Micah and Lewis, Mark A.
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Insects, especially forest pests, are frequently characterized by eruptive dynamics. These types of species can stay at low, endemic population densities for extended periods of time before erupting in large-scale outbreaks. We here present a mechanistic model of these dynamics for mountain pine beetle. This extends a recent model that describes key aspects of mountain pine beetle biology coupled with a forest growth model by additionally including a fraction of low-vigor trees. These low-vigor trees, which may represent hosts with weakened defenses from drought, disease, other bark beetles, or other stressors, give rise to an endemic equilibrium in biologically plausible parameter ranges. The mechanistic nature of the model allows us to study how each model parameter affects the existence and size of the endemic equilibrium. We then show that under certain parameter shifts that are more likely under climate change, the endemic equilibrium can disappear entirely, leading to an outbreak. [ABSTRACT FROM AUTHOR] more...
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- 2025
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5. Eruptive Insect Outbreaks from Endemic Populations Under Climate Change.
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Brush, Micah and Lewis, Mark A.
- Abstract
Insects, especially forest pests, are frequently characterized by eruptive dynamics. These types of species can stay at low, endemic population densities for extended periods of time before erupting in large-scale outbreaks. We here present a mechanistic model of these dynamics for mountain pine beetle. This extends a recent model that describes key aspects of mountain pine beetle biology coupled with a forest growth model by additionally including a fraction of low-vigor trees. These low-vigor trees, which may represent hosts with weakened defenses from drought, disease, other bark beetles, or other stressors, give rise to an endemic equilibrium in biologically plausible parameter ranges. The mechanistic nature of the model allows us to study how each model parameter affects the existence and size of the endemic equilibrium. We then show that under certain parameter shifts that are more likely under climate change, the endemic equilibrium can disappear entirely, leading to an outbreak. [ABSTRACT FROM AUTHOR] more...
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- 2025
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6. Methodology for Removing Striping Artifacts Encountered in Planet SuperDove Ocean-Color Products.
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Slocum, Brittney, Ladner, Sherwin, Lawson, Adam, Lewis, Mark David, and McCarthy, Sean
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SPECTRAL sensitivity ,SEAWATER ,REMOTE sensing ,NANOSATELLITES ,RADIANCE ,OCEAN color - Abstract
The Planet SuperDove sensors produce eight-band, three-meter resolution images covering the blue, green, red, red-edge, and NIR spectral bands. Variations in spectral response in the data used to perform atmospheric correction combined with low signal-to-noise over ocean waters can lead to visible striping artifacts in the downstream ocean-color products. It was determined that the striping artifacts could be removed from these products by filtering the top of the atmosphere radiance in the red and NIR bands prior to selecting the aerosol models, without sacrificing high-resolution features in the imagery. This paper examines an approach that applies this filtering to the respective bands as a preprocessing step. The outcome and performance of this filtering technique are examined to assess the success of removing the striping effect in atmospherically corrected Planet SuperDove data. [ABSTRACT FROM AUTHOR] more...
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- 2024
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7. Environmental Enrichment Attenuates Repetitive Behavior and Alters the Functional Connectivity of Pain and Sensory Pathways in C58 Mice.
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Farmer, Anna L., Febo, Marcelo, Wilkes, Bradley J., and Lewis, Mark H.
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FUNCTIONAL magnetic resonance imaging ,LARGE-scale brain networks ,ENVIRONMENTAL enrichment ,AUTISM spectrum disorders ,FUNCTIONAL connectivity ,THALAMIC nuclei ,THALAMOCORTICAL system - Abstract
Restricted repetitive behaviors (RRB) encompass a variety of inflexible behaviors, which are diagnostic for autism spectrum disorder (ASD). Despite being requisite diagnostic criteria, the neurocircuitry of these behaviors remains poorly understood, limiting treatment development. Studies in translational animal models show environmental enrichment (EE) reduces the expression of RRB, although the underlying mechanisms are largely unknown. This study used functional magnetic resonance imaging to identify functional connectivity alterations associated with RRB and its attenuation by EE in C58 mice, an animal model of RRB. Extensive differences were observed between C58 mice and C57BL/6 control mice. Higher RRB was associated with altered connectivity between the somatosensory network and reticular thalamic nucleus and between striatal and sensory processing regions. Animals housed in EE displayed increased connectivity between the somatosensory network and the anterior pretectal nucleus and hippocampus, as well as reduced connectivity between the visual network and area prostriata. These results suggest aberrant sensory perception is associated with RRB in C58 mice. EE may reduce RRB by altering functional connectivity in pain and visual networks. This study raises questions about the role of sensory processing and pain in RRB development and identifies new potential intervention targets. [ABSTRACT FROM AUTHOR] more...
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- 2024
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8. Identifying signals of memory from observations of animal movements.
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Kim, Dongmin, Thompson, Peter R., Wolfson, David W., Merkle, Jerod A., Oliveira-Santos, L. G. R., Forester, James D., Avgar, Tal, Lewis, Mark A., and Fieberg, John
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ANIMAL mechanics ,DISTRIBUTION (Probability theory) ,ANIMAL memory ,COGNITIVE maps (Psychology) ,TELEMETRY - Abstract
Incorporating memory (i.e., some notion of familiarity or experience with the landscape) into models of animal movement is a rising challenge in the field of movement ecology. The recent proliferation of new methods offers new opportunities to understand how memory influences movement. However, there are no clear guidelines for practitioners wishing to parameterize the effects of memory on moving animals. We review approaches for incorporating memory into step-selection analyses (SSAs), a frequently used movement modeling framework. Memory-informed SSAs can be constructed by including spatial-temporal covariates (or maps) that define some aspect of familiarity (e.g., whether, how often, or how long ago the animal visited different spatial locations) derived from long-term telemetry data. We demonstrate how various familiarity covariates can be included in SSAs using a series of coded examples in which we fit models to wildlife tracking data from a wide range of taxa. We discuss how these different approaches can be used to address questions related to whether and how animals use information from past experiences to inform their future movements. We also highlight challenges and decisions that the user must make when applying these methods to their tracking data. By reviewing different approaches and providing code templates for their implementation, we hope to inspire practitioners to investigate further the importance of memory in animal movements using wildlife tracking data. [ABSTRACT FROM AUTHOR] more...
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- 2024
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9. A Note on the Codegree of Finite Groups.
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Lewis, Mark L. and Yan, Quanfu
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Let χ be an irreducible character of a group G, and S c (G) = ∑ χ ∈ Irr (G) cod (χ) be the sum of the codegrees of the irreducible characters of G. Write fcod (G) = S c (G) | G |. We aim to explore the structure of finite groups in terms of fcod (G). On the other hand, we determine the lower bound of S c (G) for nonsolvable groups and prove that if G is nonsolvable, then S c (G) ⩾ S c (A 5) = 68 , with equality if and only if G ≅ A 5. Additionally, we show that there is a solvable group so that it has the codegree sum as A 5. [ABSTRACT FROM AUTHOR] more...
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- 2024
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10. NK cells modulate in vivo control of SARS-CoV-2 replication and suppression of lung damage.
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Balachandran, Harikrishnan, Kroll, Kyle, Terry, Karen, Manickam, Cordelia, Jones, Rhianna, Woolley, Griffin, Hayes, Tammy, Martinot, Amanda J., Sharma, Ankur, Lewis, Mark, Jost, Stephanie, and Reeves, R. Keith more...
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SARS-CoV-2 Delta variant ,KILLER cells ,PATHOLOGY ,VIRAL shedding ,SARS-CoV-2 - Abstract
Natural killer (NK) cells play a critical role in virus control. However, it has remained largely unclear whether NK cell mobilization in SARS-CoV-2 infections is beneficial or pathologic. To address this deficit, we employed a validated experimental NK cell depletion non-human primate (NHP) model with SARS-CoV-2 Delta variant B.1.617.2 challenge. Viral loads (VL), NK cell numbers, activation, proliferation, and functional measures were evaluated in blood and tissues. In non-depleted (control) animals, infection rapidly induced NK cell expansion, activation, and increased tissue trafficking associated with VL. Strikingly, we report that experimental NK cell depletion leads to higher VL, longer duration of viral shedding, significantly increased levels of pro-inflammatory cytokines in the lungs, and overt lung damage. Overall, we find the first significant and conclusive evidence for NK cell-mediated control of SARS-CoV-2 virus replication and disease pathology. These data indicate that adjunct therapies for infection could largely benefit from NK cell-targeted approaches. Author summary: Natural killer (NK) cells play a critically understudied role in controlling SARS-CoV-2 viral replication, clearance, and disease sequelae. In this manuscript, we investigated the protective role of NK cells in acute infection using a well-established NK cell depletion strategy in cynomolgus macaques (CM) and a SARS-CoV-2 delta variant infection model. Circulating NK cells exhibited an increased proliferative and activated phenotype following infection, concomitant with peak NK cell expansion at 10 days post-infection (DPI). Importantly, following experimental NK cell depletion, CM exhibited increased viral shedding and delayed viral clearance compared to controls. NK cell-depleted animals also exhibited significantly increased lung pathology and Luminex cytokine analyses of broncho-alveolar lavage (BAL) fluid showed a 5-fold increase in interferon-alpha (IFNα) compared to controls during peak infection. Collectively, our findings suggest that NK cells play a crucial role in controlling SARS-CoV-2 replication and reducing lung damage. These results underscore the potential of NK cell-based vaccines and therapies for COVID-19 and other infectious diseases, warranting further investigation in this area. [ABSTRACT FROM AUTHOR] more...
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- 2024
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11. The majority of Canadians likely behaved as myopic rationalists rather than success-based learners when deciding on their first dose of COVID-19 vaccine.
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Aghaeeyan, Azadeh, Ramazi, Pouria, and Lewis, Mark A.
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- 2024
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12. Extracellular vesicles may provide an alternative detoxification pathway during skeletal muscle myoblast ageing.
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Fernández‐Rhodes, María, Buchan, Emma, Gagnon, Stephanie D., Qian, Jiani, Gethings, Lee, Lees, Rebecca, Peacock, Ben, Capel, Andrew J., Martin, Neil R. W., Oppenheimer, Pola Goldberg, Lewis, Mark P., and Davies, Owen G. more...
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LIQUID chromatography-mass spectrometry ,CHEMICAL fingerprinting ,GEL permeation chromatography ,EXTRACELLULAR vesicles ,MUSCLE aging - Abstract
Skeletal muscle (SM) acts as a secretory organ, capable of releasing myokines and extracellular vesicles (SM‐EVs) that impact myogenesis and homeostasis. While age‐related changes have been previously reported in murine SM‐EVs, no study has comprehensively profiled SM‐EV in human models. To this end, we provide the first comprehensive comparison of SM‐EVs from young and old human primary skeletal muscle cells (HPMCs) to map changes associated with SM ageing. HPMCs, isolated from young (24 ± 1.7 years old) and older (69 ± 2.6 years old) participants, were immunomagnetically sorted based on the presence of the myogenic marker CD56 (N‐CAM) and cultured as pure (100% CD56+) or mixed populations (MP: 90% CD56+). SM‐EVs were isolated using an optimised protocol combining ultrafiltration and size exclusion chromatography (UF + SEC) and their biological content was extensively characterised using Raman spectroscopy (RS) and liquid chromatography mass spectrometry (LC‐MS). Minimal variations in basic EV parameters (particle number, size, protein markers) were observed between young and old populations. However, biochemical fingerprinting by RS highlighted increased protein (amide I), lipid (phospholipids and phosphatidylcholine) and hypoxanthine signatures for older SM‐EVs. Through LC‐MS, we identified 84 shared proteins with functions principally related to cell homeostasis, muscle maintenance and transcriptional regulation. Significantly, SM‐EVs from older participants were comparatively enriched in proteins involved in oxidative stress and DNA/RNA mutagenesis, such as E3 ubiquitin‐protein ligase TTC3 (TTC3), little elongation complex subunit 1 (ICE1) and Acetyl‐CoA carboxylase 1 (ACACA). These data suggest SM‐EVs could provide an alternative pathway for homeostasis and detoxification during SM ageing. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
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13. Environmental enrichment reduces restricted repetitive behavior by altering gray matter microstructure.
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Farmer, Anna L., Febo, Marcelo, Wilkes, Bradley J., and Lewis, Mark H.
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ENVIRONMENTAL enrichment ,DIFFUSION tensor imaging ,WHITE matter (Nerve tissue) ,AUTISM spectrum disorders ,LABORATORY mice ,ENTORHINAL cortex ,GRAY matter (Nerve tissue) - Abstract
Restricted, repetitive behaviors are common symptoms in neurodevelopmental disorders including autism spectrum disorder. Despite being associated with poor developmental outcomes, repetitive behaviors remain poorly understood and have limited treatment options. Environmental enrichment attenuates the development of repetitive behaviors, but the exact mechanisms remain obscure. Using the C58 mouse model of repetitive behavior, we performed diffusion tensor imaging to examine microstructural alterations associated with the development of repetitive behavior and its attenuation by environmental enrichment. The C57BL/6 mouse strain, which displays little or no repetitive behavior, was used as a control group. We observed widespread differences in diffusion metrics between C58 mice and C57BL/6 mice. In juvenile C58 mice, repetitive motor behavior displayed strong negative correlations with fractional anisotropy in multiple gray matter regions, whereas in young adult C58 mice, high repetitive motor behavior was most strongly associated with lower fractional anisotropy and higher radial diffusivity in the striatum. Environmental enrichment increased fractional anisotropy and axial diffusivity throughout gray matter regions in the brains of juvenile C58 mice and overlapped predominantly with cerebellar and sensory regions associated with repetitive behavior. Our results suggest environmental enrichment reduces repetitive behavior development by altering gray matter microstructure in the cerebellum, medial entorhinal cortex, and sensory processing regions in juvenile C58 mice. Under standard laboratory conditions, early pathology in these regions appears to contribute to later striatal and white matter dysfunction in adult C58 mice. Future studies should examine the role these regions play in the development of repetitive behavior and the relationship between sensory processing and cerebellar deficits and repetitive behavior. [ABSTRACT FROM AUTHOR] more...
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- 2024
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14. Arenavirus-Based Vectors Generate Robust SIV Immunity in Non-Human Primates.
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Sharma, Bhawna, Bekerman, Elena, Truong, Hoa, Lee, Johnny, Gamez-Guerrero, Maria, Boopathy, Archana, Mital, Rohit, Huang, Katell Bidet, Ahmadi-Erber, Sarah, Wimmer, Raphaela, Schulha, Sophie, Lauterbach, Henning, Orlinger, Klaus, Suthram, Silpa, Lewis, Mark G., Blair, Wade, Makadzange, Tariro, Geleziunas, Romas, Murry, Jeffrey P., and Schmidt, Sarah more...
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SIMIAN immunodeficiency virus ,ANTIBODY titer ,IMMUNE response ,ANTIBODY formation ,T cells - Abstract
Arenavirus-based vectors are being investigated as therapeutic vaccine candidates with the potential to elicit robust CD8 T-cell responses. We compared the immunogenicity of replicating (artPICV and artLCMV) and non-replicating (rPICV and rLCMV) arenavirus-based vectors expressing simian immunodeficiency virus (SIV) Gag and Envelope (Env) immunogens in treatment-naïve non-human primates. Heterologous regimens with non-replicating and replicating vectors elicited more robust SIV IFN-γ responses than a homologous regimen, and replicating vectors elicited significantly higher cellular immunogenicity than non-replicating vectors. The heterologous regimen elicited high anti-Env antibody titers when administered intravenously, with replicating vectors inducing significantly higher titers than non-replicating vectors. Intramuscular immunization resulted in more durable antibody responses than intravenous immunization for both vector platforms, with no difference between the replicating and non-replicating vectors. Overall, both replicating and non-replicating arenavirus vectors generated robust T- and B-cell-mediated immunity to SIV antigens in treatment-naïve non-human primates, supporting further evaluation of these vectors in a clinical setting for HIV therapy. [ABSTRACT FROM AUTHOR] more...
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- 2024
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15. Characterizing finite groups whose enhanced power graphs have universal vertices.
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Costanzo, David G., Lewis, Mark L., Schmidt, Stefano, Tsegaye, Eyob, and Udell, Gabe
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Let G be a finite group and construct a graph Δ(G) by taking G {1} as the vertex set of Δ(G) and by drawing an edge between two vertices x and y if 〈x, y〉 is cyclic. Let K(G) be the set consisting of the universal vertices of Δ(G) along the identity element. For a solvable group G, we present a necessary and sufficient condition for K(G) to be nontrivial. We also develop a connection between Δ(G) and K(G) when ∣G∣ is divisible by two distinct primes and the diameter of Δ(G) is 2. [ABSTRACT FROM AUTHOR] more...
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- 2024
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16. Bio-Optical Properties near a Coastal Convergence Zone Derived from Aircraft Remote Sensing Imagery and Modeling.
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Lewis, Mark David, Cayula, Stephanie, Gould Jr., Richard W., Miller, William David, Shulman, Igor, Smith, Geoffrey B., Smith, Travis A., Wang, David, and Wijesekera, Hemantha
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REMOTE sensing ,COASTS ,RADIOMETRY ,DEEP-sea moorings ,REFLECTANCE measurement ,WATER masses ,THEMATIC mapper satellite ,PHYSICAL measurements - Abstract
Bio-optical and physical measurements were collected in the Mississippi Sound (Northern Gulf of Mexico) during the spring of 2018 as part of the Integrated Coastal Bio-Optical Dynamics project. The goal was to examine the impact of atmospheric and tidal fronts on fine-scale physical and bio-optical property distributions in a shallow, dynamic, coastal environment. During a 25-day experiment, eight moorings were deployed in the vicinity of a frontal zone. For a one-week period in the middle of the mooring deployment, focused ship sampling was conducted with aircraft and unmanned aerial vehicle overflights, acquiring hyperspectral optical and thermal data. The personnel in the aircraft located visible color fronts indicating the convergence of two water masses and directed the ship to the front. Dye releases were performed on opposite sides of a front, and coincident aircraft and unmanned aerial vehicle overflights were collected to facilitate visualization of advection/mixing/dispersion processes. Radiometric calibration of the optical hyperspectral sensor was performed. Empirical Line Calibration was also performed to atmospherically correct the aircraft imagery using in situ remote sensing reflectance measurements as calibration sources. Bio-optical properties were subsequently derived from the atmospherically corrected aircraft and unmanned aerial vehicle imagery using the Naval Research Laboratory Automated Processing System. [ABSTRACT FROM AUTHOR] more...
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- 2024
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17. Patient satisfaction with nurse‐led coordination of colorectal cancer treatment: a short survey.
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Petrushnko, Wilson, Perry, Joanne, Bunjo, Zachary, Vather, Ryash, Lewis, Mark, and Sammour, Tarik
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PATIENT satisfaction ,PATIENTS' attitudes ,NURSING consultants ,ANAL cancer ,POSTOPERATIVE period ,ONCOLOGY nursing - Abstract
The article discusses patient satisfaction with nurse-led coordination of colorectal cancer treatment at The Royal Adelaide Hospital. A survey was conducted over a 10-year period, showing that patients highly value the care provided by a Colorectal Cancer Nurse Consultant (CCNC). Patients appreciated the emotional support, reduced stress, and confidence instilled by the nurse-led care model. The study suggests that increasing nurse-led coordination and follow-up in colorectal cancer survivorship could be beneficial. [Extracted from the article] more...
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- 2024
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18. FINITE SOLVABLE TIDY GROUPS ARE DETERMINED BY HALL SUBGROUPS WITH TWO PRIMES.
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BEIKE, NICOLAS F., CARLETON, RACHEL, COSTANZO, DAVID G., HEATH, COLIN, LEWIS, MARK L., LU, KAIWEN, and PEARCE, JAMIE D.
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SOLVABLE groups ,DIVISIBILITY groups - Abstract
In this paper, we investigate finite solvable tidy groups. We prove that a solvable group with order divisible by at least two primes is tidy if all of its Hall subgroups that are divisible by only two primes are tidy. [ABSTRACT FROM AUTHOR] more...
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- 2024
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19. BIPOC experiences of (anti-)racist patient engagement in adolescent and young adult oncology research: an electronic Delphi study.
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Cheung, Christabel K, Miller, Kimberly A, Goings, Trenette Clark, Thomas, Bria N, Lee, Haelim, Brandon, Rachel E, Katerere-Virima, Thuli, Helbling, Laura E, Causadias, José M, Roth, Michael E, Berthaud, Frantz M, Jones, Laundette P, Ross, Valentina A, Betz, Gail D, Simmons, Cole D, Carter, Jay, Davies, Simon J, Gilman, Megan L, Lewis, Mark A, and Lopes, Gilberto more...
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Aims: To characterize Black, Indigenous and People of Color (BIPOC) adolescent and young adult (AYA) cancer patients' experiences of patient engagement in AYA oncology and derive best practices that are co-developed by BIPOC AYAs and oncology professionals. Materials & methods: Following a previous call to action from AYA oncology professionals, a panel of experts composed exclusively of BIPOC AYA cancer patients (n = 32) participated in an electronic Delphi study. Results: Emergent themes described BIPOC AYA cancer patients' direct experiences and consensus opinion on recommendations to advance antiracist patient engagement from BIPOC AYA cancer patients and oncology professionals. Conclusion: The findings reveal high-priority practices across all phases of research and are instructional for advancing health equity. [ABSTRACT FROM AUTHOR] more...
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- 2024
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20. Bristol Beacon Levitt Bernstein.
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Lewis, Mark
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The article focuses on the completion of the Bristol Beacon transformation project by Levitt Bernstein for Bristol City Council and Bristol Music Trust. Topics include the restoration and enhancement of the Grade II-listed building, the creation of three main performance halls, and the incorporation of flexible spaces for music, education, and community engagement within the historic Victorian shell. more...
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- 2024
21. UNLOCKING GROWTH: THE POWER OF EHRs IN CHIROPRACTIC PRACTICE EXPANSION: Leverage electronic health records for sustainable practice growth.
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LEWIS, MARK and BRUNET, NADINE
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MEDICAL protocols ,INTERPROFESSIONAL relations ,HEALTH insurance reimbursement ,WORK-life balance ,DECISION making ,DATA analytics ,WORKFLOW ,ELECTRONIC health records ,SUSTAINABLE development ,QUALITY assurance ,AUTOMATION ,CHIROPRACTIC ,MEDICAL practice ,PATIENT participation - Published
- 2024
22. "False Positives, Re-Entry Programs and Long Term English Learners": Undoing Dichotomous Frames in U.S. Language Education Policy.
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Flores, Nelson and Lewis, Mark
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EDUCATION policy ,BILINGUAL students ,LANGUAGE policy ,BILINGUAL education ,LANGUAGE ability - Abstract
At the core of contemporary U.S. language education policy is the dichotomous dividing of bilingual students into English Learners (ELs) who are entitled to extra support and non-ELs who are not entitled to this support. In this article, we genealogically trace the normative assumptions that go into this framing of the issue. We begin by examining the historical development of this dichotomous grouping of bilingual students within the remedial framing of the Bilingual Education Act that, building on the verbal deprivation theory that was prominent at the time, reproduced raciolinguistic ideologies that framed the language practices of racialized bilingual students as deficient and in need of remediation. We then examine how this remedial framing provided incentives for proponents of bilingual education to advocate for limited English proficiency as broadly as possible to ensure that more students were deemed eligible for these programs. We then examine contemporary vignettes that point to the tensions that this ideological underpinning has created for contemporary U.S. language education policymakers. We end with a discussion of ways of reconceptualizing U.S. language education policy that reject the remedial orientation that has informed this dichotomous framing and is responsive to the tensions reported by these educators. [ABSTRACT FROM AUTHOR] more...
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- 2024
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23. Predicting Imminent Cyanobacterial Blooms in Lakes Using Incomplete Timely Data.
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Heggerud, Christopher M., Xu, Jingjing, Wang, Hao, Lewis, Mark A., Zurawell, Ron W., Loewen, Charlie J. G., Vinebrooke, Rolf D., and Ramazi, Pouria
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CYANOBACTERIAL blooms ,MISSING data (Statistics) ,TOXIC algae ,BAYESIAN analysis ,ALGAL blooms ,BODIES of water ,MICROCYSTIS - Abstract
Toxic cyanobacterial blooms (CBs) are becoming more frequent globally, posing a threat to freshwater ecosystems. While making long‐range forecasts is overly challenging, predicting imminent CBs is possible from precise monitoring data of the underlying covariates. It is, however, infeasibly costly to conduct precise monitoring on a large scale, leaving most lakes unmonitored or only partially monitored. The challenge is hence to build a predictive model that can use the incomplete, partially‐monitored data to make near‐future CB predictions. By using 30 years of monitoring data for 78 water bodies in Alberta, Canada, combined with data of watershed characteristics (including natural land cover and anthropogenic land use) and meteorological conditions, we train a Bayesian network that predicts future 2‐week CB with an area under the curve (AUC) of 0.83. The only monitoring data that the model needs to reach this level of accuracy are whether the cell count and Secchi depth are low, medium, or high, which can be estimated by advanced high‐resolution imaging technology or trained local citizens. The model is robust against missing values as in the absence of any single covariate, it performs with an AUC of at least 0.78. While taking a major step toward reduced‐cost, less data‐intensive CB forecasting, our results identify those key covariates that are worth the monitoring investment for highly accurate predictions. Key Points: Toxic algae blooms pose threats globally, longing for prompt predictionOur work uses less costly, incomplete data sets to make near‐future bloom predictionsWe predict blooms with area under the curve 0.83 using partial data of regional and local information [ABSTRACT FROM AUTHOR] more...
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- 2024
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24. Regular Medications in the Emergency Department Short Stay Unit (ReMedIES): Can Prescribing be Improved Without Increasing Resources?
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Jackson, Aidan B., Lewis, Mark, Meek, Robert, Kim-Blackmore, Jeniffer, Khan, Irim, Deng, Yong, Vallejo, Jaime, and Egerton-Warburton, Diana
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MEDICATION error prevention ,LENGTH of stay in hospitals ,HOSPITAL emergency services ,SCIENTIFIC observation ,CONFIDENCE intervals ,NONPRESCRIPTION drugs ,PATIENTS ,HOSPITAL admission & discharge ,PRE-tests & post-tests ,HOSPITAL wards ,DRUG prescribing ,DESCRIPTIVE statistics ,QUALITY assurance ,PHYSICIAN practice patterns ,MEDICAL prescriptions ,RESOURCE-limited settings - Abstract
Background: Hospital medication errors are frequent and may result in adverse events. Data on non-prescription of regular medications to emergency department short stay unit patients is lacking. In response to local reports of regular medication omissions, a multi-disciplinary team was tasked to introduce corrective emergency department (ED) process changes, but with no additional financing or resources. Aim: To reduce the rate of non-prescription of regular medications for patients admitted to the ED Short Stay Unit (SSU), through process change within existing resource constraints. Methods: A pre- and post-intervention observational study compared regular medication omission rates for patients admitted to the ED SSU. Included patients were those who usually took regular home medications at 08:00 or 20:00. Omissions were classified as clinically significant medications (CSMs) or non-clinically significant medications (non-CSMs). The intervention included reinforcement that the initially treating acute ED doctor was responsible for prescription completion, formal checking of prescription presence at SSU handover rounds, double-checking of prescription completeness by the overnight SSU lead nurse and junior doctor, and ED pharmacist medication reconciliation for those still identified as having regular medication non-prescription at 07:30. Results: For the 110 and 106 patients in the pre- and post-intervention periods, there was a non-significant reduction in the CSM omission rate of −11% (95% CI: −23 to 2), from 41% (95% CI: 32-50) to 30% (95% CI: 21-39). Conclusion: Non-prescription of regular CSMs for SSU patients was not significantly reduced by institution of work practice changes within existing resource constraints. [ABSTRACT FROM AUTHOR] more...
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- 2024
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25. Cortico-basal ganglia white matter microstructure is linked to restricted repetitive behavior in autism spectrum disorder.
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Wilkes, Bradley J., Archer, Derek B., Farmer, Anna L., Bass, Carly, Korah, Hannah, Vaillancourt, David E., and Lewis, Mark H.
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WHITE matter (Nerve tissue) ,AUTISM spectrum disorders ,GANGLIA ,BASAL ganglia ,GRAY matter (Nerve tissue) - Abstract
Background: Restricted repetitive behavior (RRB) is one of two behavioral domains required for the diagnosis of autism spectrum disorder (ASD). Neuroimaging is widely used to study brain alterations associated with ASD and the domain of social and communication deficits, but there has been less work regarding brain alterations linked to RRB. Methods: We utilized neuroimaging data from the National Institute of Mental Health Data Archive to assess basal ganglia and cerebellum structure in a cohort of children and adolescents with ASD compared to typically developing (TD) controls. We evaluated regional gray matter volumes from T1-weighted anatomical scans and assessed diffusion-weighted scans to quantify white matter microstructure with free-water imaging. We also investigated the interaction of biological sex and ASD diagnosis on these measures, and their correlation with clinical scales of RRB. Results: Individuals with ASD had significantly lower free-water corrected fractional anisotropy (FA
T ) and higher free-water (FW) in cortico-basal ganglia white matter tracts. These microstructural differences did not interact with biological sex. Moreover, both FAT and FW in basal ganglia white matter tracts significantly correlated with measures of RRB. In contrast, we found no significant difference in basal ganglia or cerebellar gray matter volumes. Limitations: The basal ganglia and cerebellar regions in this study were selected due to their hypothesized relevance to RRB. Differences between ASD and TD individuals that may occur outside the basal ganglia and cerebellum, and their potential relationship to RRB, were not evaluated. Conclusions: These new findings demonstrate that cortico-basal ganglia white matter microstructure is altered in ASD and linked to RRB. FW in cortico-basal ganglia and intra-basal ganglia white matter was more sensitive to group differences in ASD, whereas cortico-basal ganglia FAT was more closely linked to RRB. In contrast, basal ganglia and cerebellar volumes did not differ in ASD. There was no interaction between ASD diagnosis and sex-related differences in brain structure. Future diffusion imaging investigations in ASD may benefit from free-water estimation and correction in order to better understand how white matter is affected in ASD, and how such measures are linked to RRB. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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26. Cortico-basal ganglia white matter microstructure is linked to restricted repetitive behavior in autism spectrum disorder.
- Author
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Wilkes, Bradley J., Archer, Derek B., Farmer, Anna L., Bass, Carly, Korah, Hannah, Vaillancourt, David E., and Lewis, Mark H.
- Subjects
WHITE matter (Nerve tissue) ,AUTISM spectrum disorders ,GANGLIA ,BASAL ganglia ,GRAY matter (Nerve tissue) - Abstract
Background: Restricted repetitive behavior (RRB) is one of two behavioral domains required for the diagnosis of autism spectrum disorder (ASD). Neuroimaging is widely used to study brain alterations associated with ASD and the domain of social and communication deficits, but there has been less work regarding brain alterations linked to RRB. Methods: We utilized neuroimaging data from the National Institute of Mental Health Data Archive to assess basal ganglia and cerebellum structure in a cohort of children and adolescents with ASD compared to typically developing (TD) controls. We evaluated regional gray matter volumes from T1-weighted anatomical scans and assessed diffusion-weighted scans to quantify white matter microstructure with free-water imaging. We also investigated the interaction of biological sex and ASD diagnosis on these measures, and their correlation with clinical scales of RRB. Results: Individuals with ASD had significantly lower free-water corrected fractional anisotropy (FA
T ) and higher free-water (FW) in cortico-basal ganglia white matter tracts. These microstructural differences did not interact with biological sex. Moreover, both FAT and FW in basal ganglia white matter tracts significantly correlated with measures of RRB. In contrast, we found no significant difference in basal ganglia or cerebellar gray matter volumes. Limitations: The basal ganglia and cerebellar regions in this study were selected due to their hypothesized relevance to RRB. Differences between ASD and TD individuals that may occur outside the basal ganglia and cerebellum, and their potential relationship to RRB, were not evaluated. Conclusions: These new findings demonstrate that cortico-basal ganglia white matter microstructure is altered in ASD and linked to RRB. FW in cortico-basal ganglia and intra-basal ganglia white matter was more sensitive to group differences in ASD, whereas cortico-basal ganglia FAT was more closely linked to RRB. In contrast, basal ganglia and cerebellar volumes did not differ in ASD. There was no interaction between ASD diagnosis and sex-related differences in brain structure. Future diffusion imaging investigations in ASD may benefit from free-water estimation and correction in order to better understand how white matter is affected in ASD, and how such measures are linked to RRB. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
- Full Text
- View/download PDF
27. Simultaneous estimation of the temporal and spatial extent of animal migration using step lengths and turning angles.
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Thompson, Peter R., Harrington, Peter D., Mallory, Conor D., Lele, Subhash R., Bayne, Erin M., Derocher, Andrew E., Edwards, Mark A., Campbell, Mitch, and Lewis, Mark A.
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ANIMAL tracks ,ANIMAL mechanics ,LIFE history theory ,MIGRATORY animals ,REINDEER - Abstract
Background: Animals of many different species, trophic levels, and life history strategies migrate, and the improvement of animal tracking technology allows ecologists to collect increasing amounts of detailed data on these movements. Understanding when animals migrate is important for managing their populations, but is still difficult despite modelling advancements. Methods: We designed a model that parametrically estimates the timing of migration from animal tracking data. Our model identifies the beginning and end of migratory movements as signaled by change-points in step length and turning angle distributions. To this end, we can also use the model to estimate how an animal's movement changes when it begins migrating. In addition to a thorough simulation analysis, we tested our model on three datasets: migratory ferruginous hawks (Buteo regalis) in the Great Plains, barren-ground caribou (Rangifer tarandus groenlandicus) in northern Canada, and non-migratory brown bears (Ursus arctos) from the Canadian Arctic. Results: Our simulation analysis suggests that our model is most useful for datasets where an increase in movement speed or directional autocorrelation is clearly detectable. We estimated the beginning and end of migration in caribou and hawks to the nearest day, while confirming a lack of migratory behaviour in the brown bears. In addition to estimating when caribou and ferruginous hawks migrated, our model also identified differences in how they migrated; ferruginous hawks achieved efficient migrations by drastically increasing their movement rates while caribou migration was achieved through significant increases in directional persistence. Conclusions: Our approach is applicable to many animal movement studies and includes parameters that can facilitate comparison between different species or datasets. We hope that rigorous assessment of migration metrics will aid understanding of both how and why animals move. [ABSTRACT FROM AUTHOR] more...
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- 2024
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28. Provision of Interventional Radiology Services 2023.
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Morgan, Robert, Haslam, Philip, McCafferty, Ian, Bryant, Timothy, Clarke, Christopher, McPherson, Simon, Wells, David, Gupta, Yuri, See, Teik Choon, Lakshminarayan, Raghu, Miller, Fiona, Scott, Paul, Almazedi, Bahir, Bardgett, Harry, Barnacle, Alex, Shaida, Nadeem, Manoharan, Dinesh, Lewis, Mark, Taylor, Jeremy, and Bhat, Rajesh more...
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CLINICAL governance ,INTERVENTIONAL radiology ,GASTROINTESTINAL hemorrhage ,MEDICAL personnel ,MEDICAL students ,HYDRONEPHROSIS ,PERIPHERALLY inserted central catheters ,ALLIED health personnel - Abstract
This document provides an overview of interventional radiology services in the UK, emphasizing the importance of access to emergency procedures and the need for network arrangements between hospitals. It discusses the different types of interventional radiologists, the interventional radiology team, and the requirements for an interventional radiology theatre. The document also addresses issues such as the lack of anaesthetic provision for pediatric and adult IR procedures. It highlights the need for research and innovation in the field and concludes with a summary of key points. The article further explores the applications of interventional radiology in various medical procedures and discusses turf issues and challenges faced by the specialty, including collaboration, research, and burnout among practitioners. [Extracted from the article] more...
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- 2024
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29. THE AVERAGE OF SOME IRREDUCIBLE CHARACTER DEGREES.
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EL SHARIF, RAMADAN and LEWIS, MARK L.
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COMPLEX numbers ,FINITE groups - Abstract
We are interested in determining the bound of the average of the degrees of the irreducible characters whose degrees are not divisible by some prime p that guarantees a finite group G of odd order is p-nilpotent. There was found to be a bound which depends on the prime p. By further restricting the average by fixing a subfield k of the complex numbers and then computing the average of the degrees of the irreducible characters whose degrees are not divisible by p and have values in k, then a bound was obtained which depends on both p and k. Examples are provided which show best possible bounds. [ABSTRACT FROM AUTHOR] more...
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- 2024
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30. Literacy Intervention in Secondary Schools Exploring Educators' Beliefs and Practices about Supporting Adolescents' Literacy Learning.
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Lupo, Sarah M., Frankel, Katherine K., Lewis, Mark A., and Wilson, Ali M.
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SECONDARY schools ,EDUCATORS ,PROFESSIONAL employee training ,LITERACY ,TEENAGERS ,READING comprehension - Abstract
There is a need to better understand the complex landscape of adolescent literacy intervention as a shared responsibility across all educational stakeholders. To address this need, we examined the self-reported literacy beliefs and practices about secondary readers and literacy intervention among a group of educators (including administrators, teachers, and specialists) who participated in a year-long professional learning series focused on providing adolescents with rich and responsive literacy learning opportunities. We found that educators' beliefs and practices shifted as they developed shared understandings of asset-based mindsets and ways of supporting students' situated literacy learning and comprehension within disciplinary contexts. We offer suggestions for how to create shared learning opportunities for educators across roles and discuss implications for future research. [ABSTRACT FROM AUTHOR] more...
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- 2024
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31. Health Insurance Literacy Improvements Among Recently Diagnosed Adolescents and Young Adults With Cancer: Results From a Pilot Randomized Controlled Trial.
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Kirchhoff, Anne C., van Thiel Berghuijs, Karely M., Waters, Austin R., Kaddas, Heydon K., Warner, Echo L., Vaca Lopez, Perla L., Perez, Giselle K., Ray, Nicole, Chevrier, Amy, Allen, Karlie, Fair, Douglas B., Tomoko Tsukamoto, Lewis, Mark A., Haaland, Ben, and Park, Elyse R. more...
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DIAGNOSIS of tumors in children ,TUMOR diagnosis ,HEALTH literacy ,HEALTH services accessibility ,RESEARCH funding ,HEALTH insurance ,EVALUATION of human services programs ,PILOT projects ,STATISTICAL sampling ,QUESTIONNAIRES ,RANDOMIZED controlled trials ,DESCRIPTIVE statistics ,FINANCIAL stress ,HEALTH promotion ,COMPARATIVE studies ,PSYCHOLOGICAL tests ,PATIENT Protection & Affordable Care Act ,ADULTS - Abstract
PURPOSE Adolescents and young adults (AYAs; age 18-39 years) with cancer report needing support with health insurance. We conducted a pilot randomized controlled trial to assess the feasibility and acceptability of a virtual health insurance navigation intervention (HIAYA CHAT) to improve health insurance literacy (HIL), awareness of Affordable Care Act (ACA) protections, financial toxicity, and stress. MATERIALS AND METHODS HIAYA CHAT is a four-session navigator delivered program; it includes psychoeducation on insurance, navigating one’s plan, insurance-related laws, and managing costs. Participants were eligible if they could access an internetcapable device, were <1 year from diagnosis, and received treatment from University of Utah Healthcare or Intermountain Health systems. We assessed the feasibility, acceptability, and preliminary efficacy of HIAYA CHAT compared with usual navigation care, including HIL (nine items), insurance knowledge (13 items), ACA protections (eight items), COmprehensive Score for financial Toxicity (COST; 11 items), and Perceived Stress Scale (PSS; four items), using t tests and Cohen’s d. RESULTS From November 2020 to December 2021, N 5 86 AYAs enrolled (44.6% participation) and 89.3% completed the 5-month follow-up survey; 68.6% were female, 72.1% were White, 23.3% were Hispanic, 65.1% were age 26-39 years, and 87.2% were privately insured. Of intervention participants (n 5 45), 67.4% completed all four sessions; among an exit interview subset (n 5 10), all endorsed the program (100%). At follow-up, compared with usual navigation care, intervention participants had greater improvements in HIL, insurance and ACA protections knowledge, and PSS; effect sizes ranged from moderate to large (0.42-0.77). COST did not differ. CONCLUSION The results support the feasibility and acceptability of HIAYA CHAT with related improvements in HIL. [ABSTRACT FROM AUTHOR] more...
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- 2024
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32. p -GROUPS WITH CYCLIC OR GENERALISED QUATERNION HUGHES SUBGROUPS: CLASSIFYING TIDY p -GROUPS.
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BEIKE, NICOLAS F., CARLETON, RACHEL, COSTANZO, DAVID G., HEATH, COLIN, LEWIS, MARK L., LU, KAIWEN, and PEARCE, JAMIE D.
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QUATERNIONS ,CYCLIC codes ,SYLOW subgroups - Abstract
Let G be a p -group for some prime p. Recall that the Hughes subgroup of G is the subgroup generated by all of the elements of G with order not equal to p. In this paper, we prove that if the Hughes subgroup of G is cyclic, then G has exponent p or is cyclic or is dihedral. We also prove that if the Hughes subgroup of G is generalised quaternion, then G must be generalised quaternion. With these results in hand, we classify the tidy p -groups. [ABSTRACT FROM AUTHOR] more...
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- 2023
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33. SOLVABLE GROUPS WHOSE MONOMIAL, MONOLITHIC CHARACTERS HAVE PRIME POWER CODEGREES.
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XIAOYOU CHEN and LEWIS, MARK L.
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SOLVABLE groups - Abstract
In this note, we prove that if G is solvable and cod(χ) is a p-power for every nonlinear, monomial, monolithic χ e Irr(G) or every nonlinear, monomial, monolithic χ e IBr(G), then P is normal in G, where p is a prime and P is a Sylow p-subgroup of G. [ABSTRACT FROM AUTHOR] more...
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- 2023
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34. Assessing Planet Nanosatellite Sensors for Ocean Color Usage.
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Lewis, Mark D., Jarreau, Brittney, Jolliff, Jason, Ladner, Sherwin, Lawson, Timothy A., McCarthy, Sean, Martinolich, Paul, and Montes, Marcos
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OCEAN color ,MEASUREMENT errors ,DETECTORS ,INFRARED imaging ,ATMOSPHERIC aerosols ,ATMOSPHERIC models - Abstract
An increasing number of commercial nanosatellite-based Earth-observing sensors are providing high-resolution images for much of the coastal ocean region. Traditionally, to improve the accuracy of normalized water-leaving radiance ( n L w ) estimates, sensor gains are computed using in-orbit vicarious calibration methods. The initial series of Planet nanosatellite sensors were primarily designed for land applications and are missing a second near-infrared band, which is typically used in selecting aerosol models for atmospheric correction over oceanographic regions. This study focuses on the vicarious calibration of Planet sensors and the duplication of its red band for use in both the aerosol model selection process and as input to bio-optical ocean product algorithms. Error measurements show the calibration performed well at the Marine Optical Buoy location near Lanai, Hawaii. Further validation was performed using in situ data from the Aerosol Robotic Network—Ocean Color platform in the northern Adriatic Sea. Bio-optical ocean color products were generated and compared with products from the Visual Infrared Imaging Radiometric Suite sensor. This approach for sensor gain generation and usage proved effective in increasing the accuracy of n L w measurements for bio-optical ocean product algorithms. [ABSTRACT FROM AUTHOR] more...
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- 2023
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35. Coupling Mountain Pine Beetle and Forest Population Dynamics Predicts Transient Outbreaks that are Likely to Increase in Number with Climate Change.
- Author
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Brush, Micah and Lewis, Mark A.
- Abstract
Mountain pine beetle (MPB) in Canada have spread well beyond their historical range. Accurate modelling of the long-term dynamics of MPB is critical for assessing the risk of further expansion and informing management strategies, particularly in the context of climate change and variable forest resilience. Most previous models have focused on capturing a single outbreak without tree replacement. While these models are useful for understanding MPB biology and outbreak dynamics, they cannot accurately model long-term forest dynamics. Past models that incorporate forest growth tend to simplify beetle dynamics. We present a new model that couples forest growth to MPB population dynamics and accurately captures key aspects of MPB biology, including a threshold for the number of beetles needed to overcome tree defenses and beetle aggregation that facilitates mass attacks. These mechanisms lead to a demographic Allee effect, which is known to be important in beetle population dynamics. We show that as forest resilience decreases, a fold bifurcation emerges and there is a stable fixed point with a non-zero MPB population. We derive conditions for the existence of this equilibrium. We then simulate biologically relevant scenarios and show that the beetle population approaches this equilibrium with transient boom and bust cycles with period related to the time of forest recovery. As forest resilience decreases, the Allee threshold also decreases. Thus, if host resilience decreases under climate change, for example under increased stress from drought, then the lower Allee threshold makes transient outbreaks more likely to occur in the future. [ABSTRACT FROM AUTHOR] more...
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- 2023
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36. Ocean Color Image Sequences Reveal Diurnal Changes in Water Column Stability Driven by Air–Sea Interactions.
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Jolliff, Jason K., Smith, Travis A., Ladner, Sherwin, Jarosz, Ewa, Lewis, Mark David, Anderson, Stephanie, McCarthy, Sean, and Lawson, Adam
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OCEAN-atmosphere interaction ,OCEAN color ,OCEAN turbulence ,THERMAL instability ,FRONTS (Meteorology) ,TURBULENT mixing ,TURBIDITY - Abstract
The southward propagation of cold-air frontal boundaries into the Gulf of Mexico region initiates a cascade of coupled air–sea processes that manifests along the coastlines as an apparent brightness anomaly in the ocean color signals. Our hypothesis is that the color anomaly is largely due to the turbulent resuspension of sedimentary particles. Initially, there is significant wind-driven ocean turbulence as the frontal boundary passes, followed by the potential for sustained convective instability due to significant heat losses from the ocean surface. These cold front events occur during boreal autumn, winter, and into early spring, and the latter episodes occur in the context of the seasonally recurring thermal stratification of shelf waters. Here, we show that as stratification reasserts thermal stability in the waning days of a cold front episode, daily to hourly ocean color patterns are temporally coherent with the air–sea heat flux changes and the resulting impact on water column stability. Concomitant results from a nested, data-assimilative, and two-way coupled ocean-atmosphere numerical modeling system provides both corroboration and insight into how surface air–sea fluxes and in-water turbulent mixing manifest as hourly changes in apparent surface water turbidity due to the potential excitation and settling of reflective particles. A simple model of particle mixing and settling driven by the simulated turbulence mimics patterns seen in the satellite image sequences. This study offers a preview of potential application areas that may emerge following the launch of a dedicated ocean color geostationary sensor. [ABSTRACT FROM AUTHOR] more...
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- 2023
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37. Biomarker Testing Trends in Patients With Metastatic Colorectal Cancer Who Live in Rural Areas and Urban Clusters in the US.
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Lewis, Mark A, Stansfield, Lindsay, Kelton, John M, and Lieu, Christopher H
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RURAL conditions ,METASTASIS ,QUANTITATIVE research ,INTERVIEWING ,EARLY detection of cancer ,COLORECTAL cancer ,SURVEYS ,QUALITATIVE research ,RESEARCH funding ,TUMOR markers ,METROPOLITAN areas ,PHYSICIAN practice patterns ,INSURANCE - Abstract
Background: There is a paucity of data on biomarker testing rates in rural populations with metastatic colorectal cancer (mCRC). To assess biomarker testing practices, oncologists in rural areas and urban clusters in the US were surveyed. Materials and Methods: A web-based survey was administered to oncologists spending ≥40% of their time practicing in rural areas or urban clusters and who had treated ≥2 patients with stage IV mCRC in the prior month. Results: Ninety-nine oncologists completed the quantitative survey and 17 the qualitative interview. Among respondents, 97% reported ordering biomarker tests. Oncologists reported testing for KRAS, NRAS, BRAF, HER2, and mismatch repair deficiency/microsatellite instability in 72%, 65%, 63%, 56%, and 66% of patients with metastatic disease, respectively. Forty-one percent reported performing reflex testing. The most cited testing barriers were lack of insurance coverage, insufficient tissue samples, and long turnaround times. Conclusion: Further assessment of rural testing practices is needed. In this study, oncologists in the US were surveyed to investigate practice patterns related to biomarker testing in rural areas and urban clusters, uncover obstacles to biomarker testing, and understand the role of telehealth in metastatic colorectal cancer. [ABSTRACT FROM AUTHOR] more...
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- 2023
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38. Adaptation and Development of a Health Insurance Education Program for Adolescent and Young Adult Cancer Patients.
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Vaca Lopez, Perla L., Warner, Echo L., Waters, Austin R., van Thiel Berghuijs, Karely M., Anderson, John S., Ray, Nicole, Tsukamoto, Tomoko, Kaddas, Heydon K., Fair, Douglas, Lewis, Mark, Park, Elyse R., Perez, Giselle K., and Kirchhoff, Anne C. more...
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HEALTH education ,INTERVIEWING ,PATIENT-centered care ,HUMAN services programs ,CANCER patients ,HEALTH insurance ,DESCRIPTIVE statistics ,RESEARCH funding ,DATA analysis software ,ADULTS ,ADOLESCENCE - Abstract
Introduction: Adolescent and young adult (AYA) cancer patients report low health insurance literacy. We interviewed AYAs to gain their perspectives on the content and delivery of the Huntsman-Intermountain adolescent and young adult cancer health insurance (HIAYA CHAT) program. Methods: From October 2019 to March 2020, we interviewed N = 24 insured AYAs with cancer aged 18–39 years. Participants were recruited by study staff and social media. We elicited feedback on proposed HIAYA CHAT content including insurance terms/definitions, insurance coverage components, insurance legislation, cost management, and the suitability of the intervention delivery. Interviews were audio recorded, transcribed, and inductively analyzed using NVivo 12. We coded feedback into three categories of results: (1) delivery of HIAYA CHAT, (2) endorsements of proposed HIAYA CHAT content, and (3) recommendations to expand and improve HIAYA CHAT. Results: Participants were 58% female, 79% non-Hispanic white, and 79% receiving cancer treatment. First, AYAs felt that three to four different content areas, each 30 minutes or less, seemed feasible and that delivery should be through an online platform. Second, participants reflected on times during their treatment when having more insurance knowledge (e.g., appeals process) would have been useful, endorsing content about insurance policies, legal protections, and legislative impacts on health care costs. Third, AYAs recommended evaluating patients' health insurance literacy before starting HIAYA CHAT and wanted concrete learning tools (e.g., sample medical bills and budgeting). Conclusion: AYAs with cancer wanted health insurance education to include information about insurance policies and protections using tangible examples through an online delivery. Describing AYAs preferences for interventions may improve relevance and efficacy of the program. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT04448678. [ABSTRACT FROM AUTHOR] more...
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- 2023
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39. COVID-19–Related Employment Disruptions and Increased Financial Burden Among Survivors of Adolescent and Young Adult Cancer.
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Waters, Austin R., Kaddas, Heydon K., van Thiel Berghuijs, Karely M., Vaca Lopez, Perla L., Warner, Echo L., Ou, Judy Y., Ramsay, Joemy M., Palmer, Alexandra, Ray, Nicole, Tsukamoto, Tomoko, Fair, Douglas B., Lewis, Mark A., Linder, Lauri, Gill, David, and Kirchhoff, Anne C. more...
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CANCER patient psychology ,CONFIDENCE intervals ,FINANCIAL stress ,EMPLOYMENT ,RESEARCH funding ,SOCIODEMOGRAPHIC factors ,ODDS ratio ,COVID-19 pandemic ,EDUCATIONAL attainment ,ADULTS ,ADOLESCENCE - Abstract
Background: Financial burden is a major concern for survivors of adolescent and young adult (AYA) cancers. We identified if employment disruptions during the COVID-19 pandemic affected AYA survivors' financial burden. Methods: AYAs who were enrolled in a cancer patient navigation program were e-mailed a survey in fall 2020. Survey items included sociodemographics, employment disruption, and two measures of financial burden: COmprehensive Score for Financial Toxicity (COST) and material and behavioral financial hardship items (for any reason, COVID-19 induced, cancer induced). Financial burden outcomes were dichotomized at the median (COST = 21; financial hardship = 3). The association of employment disruptions and sociodemographics with financial burden was assessed using multivariable logistic regression models. Results: Reduced hours/job loss was reported by 24.0% of 341 participants. Survivors with a high school education or less (odds ratio [OR]: 2.70; 95% confidence interval [CI]: 1.21–6.03) or who had decreased hours or job loss (OR: 3.97; 95% CI: 2.01–7.84) had greater odds for high financial toxicity. Reduced hours/job loss was the only factor associated with high material and behavioral financial hardship for both any reason (OR: 2.75; 95% CI: 1.41–5.33) and owing to COVID-19 (OR: 4.98; 95% CI: 2.28–10.92). Cancer treatment since March 2020 was associated with cancer-induced high material and behavioral financial hardship (OR: 3.31; 95% CI: 1.96–5.58). Conclusion: Employment disruptions owing to the COVID-19 pandemic, lower education levels, and cancer treatment were associated with high financial burden among AYA cancer survivors. Our findings suggest the need for multilevel interventions to identify and address financial burden among vulnerable cancer survivors. [ABSTRACT FROM AUTHOR] more...
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- 2023
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40. Conjugacy classes of maximal cyclic subgroups.
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Bianchi, Mariagrazia, Camina, Rachel D., Lewis, Mark L., and Pacifici, Emanuele
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FROBENIUS groups ,FINITE groups ,MAXIMAL subgroups ,CONJUGACY classes ,NUMBER theory ,ABELIAN groups - Abstract
In this paper, we study the number of conjugacy classes of maximal cyclic subgroups of a finite group 퐺, denoted η (G) . First we consider the properties of this invariant in relation to direct and semi-direct products, and we characterize the normal subgroups 푁 with η (G / N) = η (G) . In addition, by applying the classification of finite groups whose nontrivial elements have prime order, we determine the structure of G / ⟨ G − ⟩ , where G − is the set of elements of 퐺 generating non-maximal cyclic subgroups of 퐺. More precisely, we show that G / ⟨ G − ⟩ is either trivial, elementary abelian, a Frobenius group or isomorphic to A 5 . [ABSTRACT FROM AUTHOR] more...
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- 2023
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41. An Equity Response to COVID-19 in Allegheny County, Pennsylvania: The Development and Work of the Black Equity Coalition.
- Author
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Gary-Webb, Tiffany L., Van Dyke, Carlyn, Abrams, Karen, Beery, Jason, Bennett, Olivia, Bey, Jamil, Brown, Fred, Conti, Tracey, Garland, Richard, Gloster, Jerome, Gradeck, Robert, Issac, Lisa, Kohler, Jared, King, Ayanna A., Lewis, Mark, Maseru, Noble, Mendez, Dara, McGlasson, Mickey, Monette, Alissa, and Ware, Kellie more...
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ANTI-racism ,COALITIONS ,COVID-19 pandemic - Abstract
From the onset of the pandemic in the United States, racial disparities in COVID-19 outcomes have been evident. In April 2020, several events prompted a concerned group of colleagues to form the Black Equity Coalition (BEC), a Black-led coalition in Allegheny County, Pennsylvania, which brings together professionals from multiple sectors who aim to ensure an equitable response to the COVID-19 pandemic. Several significant milestones have been achieved, and this article describes the development, functioning, and outcomes of the Coalition in the first 15 months of operation (April 2020–June 2021). COVID-19 was the reason for such an unprecedented effort, but this BEC infrastructure will be needed long after COVID-19 is controlled. In addition to short-term activities and reactive measures to prevent and mitigate COVID-19 in Black populations, the BEC is serving as a crucial link between government, health care stakeholders, and communities to produce long-term systemic change. [ABSTRACT FROM AUTHOR] more...
- Published
- 2023
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42. Consensus report of the 2021 National Cancer Institute neuroendocrine tumor clinical trials planning meeting.
- Author
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Singh, Simron, Hope, Thomas A, Bergsland, Emily B, Bodei, Lisa, Bushnell, David L, Chan, Jennifer A, Chasen, Beth R, Chauhan, Aman, Das, Satya, Dasari, Arvind, Rivero, Jaydira Del, El-Haddad, Ghassan, Goodman, Karyn A, Halperin, Daniel M, Lewis, Mark A, Lindwasser, O Wolf, Myrehaug, Sten, Raj, Nitya P, Reidy-Lagunes, Diane L, and Soares, Heloisa P more...
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NEUROENDOCRINE tumors ,CLINICAL trials ,MEETING planning ,AMINO acid sequence ,PEPTIDE receptors - Abstract
Important progress has been made over the last decade in the classification, imaging, and treatment of neuroendocrine neoplasm (NENs), with several new agents approved for use. Although the treatment options available for patients with well-differentiated neuroendocrine tumors (NETs) have greatly expanded, the rapidly changing landscape has presented several unanswered questions about how best to optimize, sequence, and individualize therapy. Perhaps the most important development over the last decade has been the approval of
177 Lu-DOTATATE for treatment of gastroenteropancreatic-NETs, raising questions around optimal sequencing of peptide receptor radionuclide therapy (PRRT) relative to other therapeutic options, the role of re-treatment with PRRT, and whether PRRT can be further optimized through use of dosimetry among other approaches. The NET Task Force of the National Cancer Institute GI Steering Committee convened a clinical trial planning meeting in 2021 with multidisciplinary experts from academia, the federal government, industry, and patient advocates to develop NET clinical trials in the era of PRRT. Key clinical trial recommendations for development included 1) PRRT re-treatment, 2) PRRT and immunotherapy combinations, 3) PRRT and DNA damage repair inhibitor combinations, 4) treatment for liver-dominant disease, 5) treatment for PRRT-resistant disease, and 6) dosimetry-modified PRRT. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
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43. Two‐class constrained optimization with applications to queueing control.
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Girard, Cory, Green, Linda V., Lewis, Mark E., and Xie, Jingui
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CONSTRAINED optimization ,LAGRANGE multiplier ,MARKOV processes ,MANUFACTURING processes ,CALL centers - Abstract
Constrained Markov decision process (CMDP) is a methodology that has not seen wide applications in the literature, but is a more natural specification for modeling preferences in modern service systems. In this paper we present a general framework for solving two‐class CMDPs. In particular, we show that CMDPs can be solved by using the Lagrangian dual to specify a particular unconstrained problem. If an appropriate Lagrange multiplier can be discerned, structural results can be exploited to solve the original CMDP with the appropriate structure. We show that for two queues in parallel or two queues in series, the framework leads to simple threshold‐like optimal policies. The results in each case are used to develop heuristics for analogous problems with abandonments with applications to health care, call centers, and manufacturing systems. The efficacy of the heuristics is verified in each case via a detailed numerical study. [ABSTRACT FROM AUTHOR] more...
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- 2023
- Full Text
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44. The Many Lives of the First Emperor of China.
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Lewis, Mark Edward
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EMPERORS ,STATE power ,ROMAN emperors ,ASSASSINATION attempts ,ROMAN law - Abstract
Like the First Emperor, Augustus created both the title and form of the emperor, and like the former he was both celebrated for his achievements and condemned for his cruelty and deceitfulness in climbing to power. Accounts mock the First Emperor's paranoia in hiding away behind covered passageways, but the emperor's invisibility was an ideal from the early Han. These additional approaches to examining Qin and the First Emperor are not offered as criticisms of Barbieri-Low, who has provided more than anyone could demand, but instead as further demonstrations of the validity of his argument that the First Emperor is indeed "good to think.". [Extracted from the article] more...
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- 2023
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45. Comparison of extracellular vesicle isolation processes for therapeutic applications.
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Williams, Soraya, Fernandez-Rhodes, Maria, Law, Alice, Peacock, Ben, Lewis, Mark P., and Davies, Owen G.
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EXTRACELLULAR vesicles ,GEL permeation chromatography ,POLYETHYLENE glycol ,TETRASPANIN ,ANNEXINS - Abstract
While extracellular vesicles (EVs) continue to gain interest for therapeutic applications, their clinical translation is limited by a lack of optimal isolation methods. We sought to determine how universally applied isolation methods impact EV purity and yield. EVs were isolated by ultracentrifugation (UC), polyethylene glycol precipitation, Total Exosome Isolation Reagent, an aqueous two-phase system with and without repeat washes or size exclusion chromatography (SEC). EV-like particles could be detected for all isolation methods but varied in their purity and relative expression of surface markers (Alix, Annexin A2, CD9, CD63 and CD81). Assessments of sample purity were dependent on the specificity of characterisation method applied, with total particle counts and particle to protein (PtP) ratios often not aligning with quantitative measures of tetraspanin surface markers obtained using high-resolution nano-flow cytometry. While SEC resulted in the isolation of fewer particles with a relatively low PtP ratio (1.12 × 10
7 ± 1.43 × 106 vs highest recorded; ATPS/R 2.01 × 108 ± 1.15 × 109 , p ⩽ 0.05), EVs isolated using this method displayed a comparatively high level of tetraspanin positivity (e.g. ExoELISA CD63⁺ particles; 1.36 × 1011 ± 1.18 × 1010 vs ATPS/R 2.58 × 1010 ± 1.92 × 109 , p ⩽ 0.001). Results originating from an accompanying survey designed to evaluate pragmatic considerations surrounding method implementation (e.g. scalability and cost) identified that SEC and UC were favoured for overall efficiency. However, reservations were highlighted in the scalability of these methods, which could potentially hinder downstream therapeutic applications. In conclusion, variations in sample purity and yield were evident between isolation methods, while standard non-specific assessments of sample purity did not align with advanced quantitative high-resolution analysis of EV surface markers. Reproducible and specific assessments of EV purity will be critical for informing therapeutic studies. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
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46. Boosting propagule transport models with individual‐specific data from mobile apps.
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Fischer, Samuel M., Ramazi, Pouria, Simmons, Sean, Poesch, Mark S., and Lewis, Mark A.
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MOBILE apps ,INDIVIDUALS' preferences ,INTRODUCED animals ,FISH diseases ,ANIMAL diseases ,CANADIAN provinces - Abstract
Management of invasive species and pathogens requires information about the traffic of potential vectors. Such information is often taken from vector traffic models fitted to survey data. Here, user‐specific data collected via mobile apps offer new opportunities to obtain more accurate estimates and to analyse how vectors' individual preferences affect propagule flows. However, data voluntarily reported via apps may lack some trip records, adding a significant layer of uncertainty. We show how the benefits of app‐based data can be exploited despite this drawback.Based on data collected via an angler app, we built a stochastic model for angler traffic in the Canadian province Alberta. There, anglers facilitate the spread of whirling disease, a parasite‐induced fish disease. The model is temporally and spatially explicit and accounts for individual preferences and repeating behaviour of anglers, helping to address the problem of missing trip records.We obtained estimates of angler traffic between all subbasins in Alberta. The model's accuracy exceeds that of direct empirical estimates even when fewer data were used to fit the model. The results indicate that anglers' local preferences and their tendency to revisit previous destinations reduce the number of long interwaterbody trips potentially dispersing whirling disease. According to our model, anglers revisit their previous destination in 64% of their trips, making these trips irrelevant for the spread of whirling disease. Furthermore, 54% of fishing trips end in individual‐specific spatially contained areas with mean radius of 54.7 km. Finally, although the fraction of trips that anglers report was unknown, we were able to estimate the total yearly number of fishing trips in Alberta, matching an independent empirical estimate.Policy implications. We make two major contributions: (1) we provide a model that uses mobile app data to boost the mechanistic accuracy of classic propagule transport models, and (2) we demonstrate the importance of individual‐specific behaviour of vectors for propagule transport. Ignoring vectors' local preferences and their tendency to revisit previous destinations can lead to significant overestimates of vector traffic and biased estimates of propagule flows. This has clear implications for the management of invasive species and animal diseases. [ABSTRACT FROM AUTHOR] more...
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- 2023
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47. Next‐generation matrices for marine metapopulations: The case of sea lice on salmon farms.
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Harrington, Peter D., Cantrell, Danielle L., and Lewis, Mark A.
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SALMON farming ,LEPEOPHTHEIRUS salmonis ,AGRICULTURAL intensification ,PROVINCIAL governments ,RURAL population - Abstract
Classifying habitat patches as sources or sinks and determining metapopulation persistence requires coupling connectivity between habitat patches with local demographic rates. While methods to calculate sources, sinks, and metapopulation persistence exist for discrete‐time models, there is no method that is consistent across modeling frameworks. In this paper, we show how next‐generation matrices, originally popularized in epidemiology to calculate new infections after one generation, can be used in an ecological context to calculate sources and sinks as well as metapopulation persistence in marine metapopulations. To demonstrate the utility of the method, we construct a next‐generation matrix for a network of sea lice populations on salmon farms in the Broughton Archipelago, BC, an intensive salmon farming region on the west coast of Canada where certain salmon farms are currently being removed under an agreement between local First Nations and the provincial government. The column sums of the next‐generation matrix can determine if a habitat patch is a source or a sink and the spectral radius of the next‐generation matrix can determine the persistence of the metapopulation. With respect to salmon farms in the Broughton Archipelago, we identify the salmon farms which are acting as the largest sources of sea lice and show that in this region the most productive sea lice populations are also the most connected. The farms which are the largest sources of sea lice have not yet been removed from the Broughton Archipelago, and warming temperatures could lead to increased sea louse growth. Calculating sources, sinks, and persistence in marine metapopulations using the next‐generation matrix is biologically intuitive, mathematically equivalent to previous methods, and consistent across different modeling frameworks. [ABSTRACT FROM AUTHOR] more...
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- 2023
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48. Point‐of‐care Analysis for Non‐invasive Diagnosis of Oral cancer (PANDORA): A technology‐development proof of concept diagnostic accuracy study of dielectrophoresis in patients with oral squamous cell carcinoma and dysplasia.
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Hughes, Michael P., Labeed, Fatima H., Hoettges, Kai F., Porter, Stephen, Mercadante, Valeria, Kalavrezos, Nicholas, Liew, Colin, McCaul, James A., Kulkarni, Raghav, Cymerman, James, Kerawala, Cyrus, Barber, Julie, Lewis, Mark P., and Fedele, Stefano more...
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ORAL cancer diagnosis ,SQUAMOUS cell carcinoma ,DYSPLASIA ,CELLULAR pathology ,DIELECTROPHORESIS - Abstract
Background: Delays in the identification and referral of oral cancer remain frequent. An accurate and non‐invasive diagnostic test to be performed in primary care may help identifying oral cancer at an early stage and reduce mortality. Point‐of‐care Analysis for Non‐invasive Diagnosis of Oral cancer (PANDORA) was a proof‐of‐concept prospective diagnostic accuracy study aimed at advancing the development of a dielectrophoresis‐based diagnostic platform for oral squamous cell carcinoma (OSCC) and epithelial dysplasia (OED) using a novel automated DEPtech 3DEP analyser. Methods: The aim of PANDORA was to identify the set‐up of the DEPtech 3DEP analyser associated with the highest diagnostic accuracy in identifying OSCC and OED from non‐invasive brush biopsy samples, as compared to the gold standard test (histopathology). Measures of accuracy included sensitivity, specificity, positive and negative predictive value. Brush biopsies were collected from individuals with histologically proven OSCC and OED, histologically proven benign mucosal disease, and healthy mucosa (standard test), and analysed via dielectrophoresis (index test). Results: 40 individuals with OSCC/OED and 79 with benign oral mucosal disease/healthy mucosa were recruited. Sensitivity and specificity of the index test was 86.8% (95% confidence interval [CI], 71.9%–95.6%) and 83.6% (95% CI, 73.0%–91.2%). Analysing OSCC samples separately led to higher diagnostic accuracy, with 92.0% (95% CI, 74.0%–99.0%) sensitivity and 94.5% (95% CI, 86.6%–98.5%) specificity. Conclusion: The DEPtech 3DEP analyser has the potential to identify OSCC and OED with notable diagnostic accuracy and warrants further investigation as a potential triage test in the primary care setting for patients who may need to progress along the diagnostic pathway and be offered a surgical biopsy. [ABSTRACT FROM AUTHOR] more...
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- 2023
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49. Exploring the microstructure of hydrated collagen hydrogels under scanning electron microscopy.
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Merryweather, Daniel J., Weston, Nicola, Roe, Jordan, Parmenter, Christopher, Lewis, Mark P., and Roach, Paul
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SCANNING electron microscopy ,HAIR analysis ,COLLAGEN ,POROUS materials ,MICROSTRUCTURE ,MATERIALS handling ,HYDROGELS - Abstract
Collagen hydrogels are a rapidly expanding platform in bioengineering and soft materials engineering for novel applications focused on medical therapeutics, medical devices and biosensors. Observations linking microstructure to material properties and function enables rational design strategies to control this space. Visualisation of the microscale organisation of these soft hydrated materials presents unique technical challenges due to the relationship between hydration and the molecular organisation of a collagen gel. Scanning electron microscopy is a robust tool widely employed to visualise and explore materials on the microscale. However, investigation of collagen gel microstructure is difficult without imparting structural changes during preparation and/or observation. Electrons are poorly propagated within liquid‐phase materials, limiting the ability of electron microscopy to interrogate hydrated gels. Sample preparation techniques to remove water induce artefactual changes in material microstructure particularly in complex materials such as collagen, highlighting a critical need to develop robust material handling protocols for the imaging of collagen hydrogels. Here a collagen hydrogel is fabricated, and the gel state explored under high‐vacuum (10−6 Pa) and low‐vacuum (80–120 Pa) conditions, and in an environmental SEM chamber. Visualisation of collagen fibres is found to be dependent on the degree of sample hydration, with higher imaging chamber pressures and humidity resulting in decreased feature fidelity. Reduction of imaging chamber pressure is used to induce evaporation of gel water content, revealing collagen fibres of significantly larger diameter than observed in samples dehydrated prior to imaging. Rapid freezing and cryogenic handling of the gel material is found to retain a porous 3D structure following sublimation of the gel water content. Comparative analysis of collagen hydrogel materials demonstrates the care needed when preparing hydrogel samples for electron microscopy. Lay Description: In order to support the development of engineered living tissues, materials scientists and biologists have been making use of soft, porous materials that have a high proportion of water within their structure similar to environments found within the body. These can be used for the delivery of cells for medical therapies or used within the laboratory to grow artificial tissues as models, along with other applications. One of the main factors affecting the performance of these water‐filled gels (hydrogels) is the physical structure at the micro‐scale (roughly one tenth the thickness of a human hair). Visualisation of these structures is difficult, with many methods requiring water to be removed prior to analysis. However, by removing or freezing the water contained within, small structural features are put under immense stress and often suffer damage, such that the structure observed is not what would normally be presented to living cells in normal circumstances. New technologies enable different ways of measuring and assessing samples. Here we present the visualisation of collagen hydrogels using a number of methods where their original structures are retained. Here a collagen hydrogel is analysed using scanning electron microscopy methods in different ways: under vacuum where water is removed, under low pressure, and normal atmospheric pressure, with water retained and visualised with the collagen. We show the native structures formed in these collagen hydrogels and how they are altered upon visualisation under the different imaging conditions. These results are useful to a broad audience, particularly those working on medical related materials, who may not fully appreciate the structures observed in normal hydrated conditions. [ABSTRACT FROM AUTHOR] more...
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- 2023
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50. Protection from COVID-19 disease in hamsters vaccinated with subunit SARS-CoV-2 S1 mucosal vaccines adjuvanted with different adjuvants.
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Yongjun Sui, Andersen, Hanne, Jianping Li, Tanya Hoang, Bekele, Yonas, Kar, Swagata, Lewis, Mark G., and Berzofsky, Jay A.
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COVID-19 ,SARS-CoV-2 ,HAMSTERS ,VACCINATION ,SARS-CoV-2 Omicron variant - Abstract
Introduction: Adjuvant plays an important role in directing the immune responses induced by vaccines. In previous studies, we have shown that a mucosal SARS-CoV-2 S1 subunit vaccine adjuvanted with a combination of CpG, Poly I:C and IL-15 (named CP15) induced effective mucosal and systemic immunity and conferred nearly sterile protection against SARS-CoV-2 viral replication in macaque models. Methods: In this study, we used a hamster model, which mimics the human scenario and reliably exhibits severe SARS-CoV-2 disease similar to hospitalized patients, to investigate the protection efficacy of the vaccines against COVID-19 disease. We compared the weight loss, viral loads (VLs), and clinical observation scores of three different vaccine regimens. All three regimens consisted of priming/boosting with S1 subunit vaccines, but adjuvanted with alum and/or CP15 administrated by either intramuscular (IM) or intranasal (IN) routes: Group 1 was adjuvanted with alum/alum administrated IM/IM; Group 2 was alum-IM/CP15-IN; and Group 3 was CP15-IM/CP15-IN. Results: After challenge with SARS-CoV-2 WA strain, we found that the alum/CP15 group showed best protection against weight loss, while the CP15 group demonstrated best reduction of oral SARS-CoV-2 VLs, suggesting that the protection profiles were different. Sex differences for VL and clinical scores were observed. Humoral immunity was induced but not correlated with protection. Moreover, S1-specific binding antibody titers against beta, omicron BA.1, and BA.2 variants showed 2.6-, 4.9- and 2.8- fold reduction, respectively, compared to the Wuhan strain. Discussion: Overall, the data suggested that adjuvants in subunit vaccines determine the protection profiles after SARS-CoV-2 infection and that nasal/oral mucosal immunization can protect against systemic COVID-19 disease. [ABSTRACT FROM AUTHOR] more...
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- 2023
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