73,403 results on '"Holman, A. A."'
Search Results
202. A language of recalcitrance: Lis Rhodes, Gertrude Stein, and syntactical play
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
203. ‘Criminal, loner, drifter': metonymic citation in the collages of David Wojnarowicz
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
204. ‘My Funny Verlainetine': queer citations in Ray Johnson's mail art
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
205. ‘Swarming city, city gorged with dreams': sound, sight, and text in Paris Blues
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
206. Part II Collage and influence
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
207. ‘Written honour': Wagner, Beuys, and Stendhal in Marcel Broodthaers's Magie: art et politique
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Chloë Julius, Michael Green, and Matthew Holman
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- 2024
208. Feeding pomegranate pulp to Ghezel lambs for enhanced productivity and meat quality
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Zabihollah Nemati, Saeid Amirdahri, Ardashir Asgari, Akbar Taghizadeh, Shahida Anusha Siddiqui, Magsoud Besharati, Kazem Alirezalu, and Benjamin W.B. Holman
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Pomegranate pulp ,Lamb meat ,Agrifood by-product ,Total mixed ration ,Liveweight ,Water holding capacity ,Veterinary medicine ,SF600-1100 - Abstract
Agrifood by-products contain nutrients and bioactive compounds that can be used in the diets of livestock – thereby value-adding to an otherwise waste product of environmental and economic significance. This study investigated the effect of dietary pomegranate pulp in the total mixed ration of Ghezel lambs, evaluating its effect on growth performance, blood parameters, carcass traits, as well as meat quality and shelf life. 3-month-old Ghezel lambs (individually housed, n = 8) were randomly assigned to be either non-supplemented (control) or supplemented with 100 g/kg DM of sun-dried pomegranate pulp for 28 days, post-adjustment. Results showed that supplementation of lamb diets with pomegranate pulp significantly increased liveweight and average daily gains, while not significantly affecting dry matter intake. Lamb serum urea and alkaline phosphatase concentrations and hot carcass weight were increased with pomegranate pulp supplementation. Compared to control lambs, the meat from lambs fed the supplemented diet had higher concentrations of intramuscular fat, mono- and polyunsaturated fatty acid, total unsaturated fatty acid, and meat phenolic compounds. Pomegranate pulp supplemented lambs also had a higher ratio of polyunsaturated to saturated fatty acids; and produced liver tissue with less fat and ash contents. Meat oxidative status (thiobarbituric acid reactive substance) and quality (water holding capacity, colour, and pH) were improved when lambs were supplemented with pomegranate pulp. These findings demonstrate that using pomegranate pulp as a feed for Ghezel lambs has advantageous effects on animal performance and meat quality, offering valorisation of an agrifood by-product.
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- 2024
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209. The quality and nutritional value of beef from Angus steers fed different levels of humate (K Humate S100R)
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Forough Ataollahi, John W. Piltz, Geoff R. Casburn, and Benjamin W.B. Holman
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Numate supplementation ,Beef ,Fatty acids ,Mineral profile ,Color stability ,Tenderness ,Veterinary medicine ,SF600-1100 - Abstract
This study compared the effect of four levels of K Humate S100R (potassium humate) supplementation on the quality, shelf-life, and nutritional properties of beef. Angus steers (n = 40) were individually housed and fed either 0, 35, 70, or 140 g K Humate S100R/animal/day for 100 days, following a 30 day adjustment period. The steers were slaughtered at the completion of the feeding study. The left m. longissimus lumborum (LL) was collected at 24 h post-mortem and aged for either 2 or 6 weeks before analysis. K Humate S100R supplementation did not affect beef drip loss, cooking loss, shear force, sarcomere length, ultimate pH, intramuscular fat content, or total volatile basic nitrogen concentrations (P > 0.05). Steers supplemented with 70 g/day K Humate S100R produced beef with higher a* values on Days 1 and 3 of retail display (P < 0.05). Beef mineral composition was unchanged by K Humate S100R supplementation (P > 0.05), but there were minor changes to the fatty acid profile. Specifically, the ratio of omega-6 to omega-3 (P < 0.05) and C20:2n-6 concentrations (P < 0.05) increased with supplementation level. Together, these results demonstrate no detrimental effects on beef quality and shelf-life as a result of K Humate S100R supplementation.
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- 2024
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210. Acute-on-chronic: using magnetic resonance imaging to disentangle the haemodynamic responses to acute and chronic fetal hypoxaemia
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Jack R. T. Darby, Brahmdeep S. Saini, Stacey L. Holman, Sarah J. Hammond, Sunthara Rajan Perumal, Christopher K. Macgowan, Mike Seed, and Janna L. Morrison
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MRI ,fetus ,hypoxaemia ,acute hypoxaemia ,chronic hypoxaemia ,hypoxia ,Medicine (General) ,R5-920 - Abstract
IntroductionThe fetal haemodynamic response to acute episodes of hypoxaemia are well characterised. However, how these responses change when the hypoxaemia becomes more chronic in nature such as that associated with fetal growth restriction (FGR), is less well understood. Herein, we utilised a combination of clinically relevant MRI techniques to comprehensively characterize and differentiate the haemodynamic responses occurring during acute and chronic periods of fetal hypoxaemia.MethodsPrior to conception, carunclectomy surgery was performed on non-pregnant ewes to induce FGR. At 108–110 days (d) gestational age (GA), pregnant ewes bearing control (n = 12) and FGR (n = 9) fetuses underwent fetal catheterisation surgery. At 117–119 days GA, ewes underwent MRI sessions where phase-contrast (PC) and T2 oximetry were used to measure blood flow and oxygenation, respectively, throughout the fetal circulation during a normoxia and then an acute hypoxia state.ResultsFetal oxygen delivery (DO2) was lower in FGR fetuses than controls during the normoxia state but cerebral DO2 remained similar between fetal groups. Acute hypoxia reduced both overall fetal and cerebral DO2. FGR increased ductus venosus (DV) and foramen ovale (FO) blood flow during both the normoxia and acute hypoxia states. Pulmonary blood flow (PBF) was lower in FGR fetuses during the normoxia state but similar to controls during the acute hypoxia state when PBF in controls was decreased.ConclusionDespite a prevailing level of chronic hypoxaemia, the FGR fetus upregulates the preferential streaming of oxygen-rich blood via the DV-FO pathway to maintain cerebral DO2. However, this upregulation is unable to maintain cerebral DO2 during further exposure to an acute episode of hypoxaemia. The haemodynamic alterations required at the level of the liver and lung to allow the DV-FO pathway to maintain cerebral DO2, may have lasting consequences on hepatic function and pulmonary vascular regulation after birth.
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- 2024
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211. Parent attitudes towards data sharing in developmental science [version 2; peer review: 2 approved]
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Rebecca Holman, Jannath Begum Ali, Siofra Heraty, Amy L. Goodwin, and Emily J.H. Jones
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Open science ,data sharing ,typical development ,Autism spectrum disorder ,neurodevelopmental conditions ,developmental science ,eng ,Science ,Social Sciences - Abstract
Background Data sharing in developmental science is increasingly encouraged, supported by funder and publisher mandates for open data access. Data sharing can accelerate discovery, link researchers with high quality analytic expertise to researchers with large datasets and democratise the research landscape to enable researchers with limited funding to access large sample sizes. However, there are also significant privacy and security concerns, in addition to conceptual and ethical considerations. These are particularly acute for developmental science, where child participants cannot consent themselves. As we move forward into a new era of data openness, it is essential that we adequately represent the views of stakeholder communities in designing data sharing efforts. Methods We conducted a comprehensive survey of the opinions of 195 parents on data sharing in developmental science. Survey themes included how widely parents are willing to share their child’s data, which type of organisations they would share the data with and the type of consent they would be comfortable providing. Results Results showed that parents were generally supportive of curated, but not open, data sharing. In addition to individual privacy and security concerns, more altruistic considerations around the purpose of research were important. Parents overwhelmingly supported nuanced consenting models in which preferences for particular types of data sharing could be changed over time. This model is different to that implemented in the vast majority of developmental science research and is contrary to many funder or publisher mandates. Conclusions The field should look to create shared repositories that implement features such as dynamic consent and mechanisms for curated sharing that allow consideration of the scientific questions addressed. Better communication and outreach are required to build trust in data sharing, and advanced analytic methods will be required to understand the impact of selective sharing on reproducibility and representativeness of research datasets.
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- 2024
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212. Quality Improvement Project: Lithium Monitoring in an Older Adult Community Mental Health Team
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Aoife Nechowska and Rebecca Holman
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Psychiatry ,RC435-571 - Abstract
Aims The aim of this project is to improve the monitoring of patients on lithium under the South Gloucestershire Later Life Community Mental Health Team and to clarify the process for this monitoring with the aim of improving patient care and safety. We aim to try to achieve 100% compliance with agreed standards based on NICE and Trust guidelines. Methods Following a meeting with team medics we agreed a series of nine standards derived from local and national guidelines. We then used a locally held database of patients on the later life CMHT caseload on lithium therapy to identify our sample and devised a simple audit tool to collate the information. We used Rio electronic health records and ICE blood results to obtain baseline data from June 2022 to December 2022. We used the plan-do-study-act (PDSA) cycle model for quality improvement. Following analysis of the baseline data, we planned and implemented key changes of the physical health nursing team taking over investigations from primary care and utilising a bespoke database. We also completed an education session for staff. Following these changes, data was collected and analysed from June until November 2023. From the analysis of these results, a further change was planned for PDSA cycle 2 and further data collection is planned. Results Results from baseline data showed that six out of eight standards had compliance of < 60%, which included the time-sensitive investigations such as lithium levels every 3 months; kidney function tests every 3–6 months; calcium level every 6 months. Weight/BMI monitoring and documentation of side effects also had poor results. Average compliance across all standards was 57%. Following the agreed steps to improve compliance, PDSA cycle 1 results showed improvement across the board, with average compliance increasing to 94%. Time-sensitive investigations now had 100% compliance (lithium level, kidney function, calcium level). Areas for improvement remain, namely in weight/BMI monitoring every 6 months and clear action plans for results falling out of range being clearly documented in patient notes. Conclusion By working closely with the physical health nursing team to devise a bespoke local database of information and taking over the investigations from primary care, we have shown an improvement across all standards, therefore improving the quality of care and patient safety.
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- 2024
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213. Protocol for a double-blind placebo-controlled randomised controlled trial assessing the impact of oral semaglutide in amyloid positivity (ISAP) in community dwelling UK adults
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Catherine J Mummery, Henrik Zetterberg, Rury R Holman, Brian Tom, Ivan Koychev, Peter Hellyer, Amanda I Adler, Elizabeth Coulthard, Benjamin R Underwood, Adam Hampshire, Charles Marshall, Paul Edison, Joanne E Milton, Joe Butchart, and Francesca Cormack
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Medicine - Abstract
Introduction Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), currently marketed for type 2 diabetes and obesity, may offer novel mechanisms to delay or prevent neurotoxicity associated with Alzheimer’s disease (AD). The impact of semaglutide in amyloid positivity (ISAP) trial is investigating whether the GLP-1 RA semaglutide reduces accumulation in the brain of cortical tau protein and neuroinflammation in individuals with preclinical/prodromal AD.Methods and analysis ISAP is an investigator-led, randomised, double-blind, superiority trial of oral semaglutide compared with placebo. Up to 88 individuals aged ≥55 years with brain amyloid positivity as assessed by positron emission tomography (PET) or cerebrospinal fluid, and no or mild cognitive impairment, will be randomised. People with the low-affinity binding variant of the rs6971 allele of the Translocator Protein 18 kDa (TSPO) gene, which can interfere with interpreting TSPO PET scans (a measure of neuroinflammation), will be excluded.At baseline, participants undergo tau, TSPO PET and MRI scanning, and provide data on physical activity and cognition. Eligible individuals are randomised in a 1:1 ratio to once-daily oral semaglutide or placebo, starting at 3 mg and up-titrating to 14 mg over 8 weeks. They will attend safety visits and provide blood samples to measure AD biomarkers at weeks 4, 8, 26 and 39. All cognitive assessments are repeated at week 26. The last study visit will be at week 52, when all baseline measurements will be repeated. The primary end point is the 1-year change in tau PET signal.Ethics and dissemination The study was approved by the West Midlands—Edgbaston Research Ethics Committee (22/WM/0013). The results of the study will be disseminated through scientific presentations and peer-reviewed publications.Trial registration number ISRCTN71283871.
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- 2024
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214. Aging impairs cold-induced beige adipogenesis and adipocyte metabolic reprogramming
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Corey D Holman, Alexander P Sakers, Ryan P Calhoun, Lan Cheng, Ethan C Fein, Christopher Jacobs, Linus Tsai, Evan D Rosen, and Patrick Seale
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beige adipocyte ,UCP1 ,cold exposure ,aging ,beige adipogenesis ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
The energy-burning capability of beige adipose tissue is a potential therapeutic tool for reducing obesity and metabolic disease, but this capacity is decreased by aging. Here, we evaluate the impact of aging on the profile and activity of adipocyte stem and progenitor cells (ASPCs) and adipocytes during the beiging process in mice. We found that aging increases the expression of Cd9 and other fibro-inflammatory genes in fibroblastic ASPCs and blocks their differentiation into beige adipocytes. Fibroblastic ASPC populations from young and aged mice were equally competent for beige differentiation in vitro, suggesting that environmental factors suppress adipogenesis in vivo. Examination of adipocytes by single nucleus RNA-sequencing identified compositional and transcriptional differences in adipocyte populations with aging and cold exposure. Notably, cold exposure induced an adipocyte population expressing high levels of de novo lipogenesis (DNL) genes, and this response was severely blunted in aged animals. We further identified Npr3, which encodes the natriuretic peptide clearance receptor, as a marker gene for a subset of white adipocytes and an aging-upregulated gene in adipocytes. In summary, this study indicates that aging blocks beige adipogenesis and dysregulates adipocyte responses to cold exposure and provides a resource for identifying cold and aging-regulated pathways in adipose tissue.
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- 2024
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215. Generating human artery and vein cells from pluripotent stem cells highlights the arterial tropism of Nipah and Hendra viruses.
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Liu, Kevin, Chen, Angela, Xiong, Xiaochen, Curtis, Matthew, Martin, Renata, Raftry, Brian, Ng, Chun, Vogel, Uwe, Lander, Angelika, Lesch, Benjamin, Fowler, Jonas, Holman, Alyssa, Chai, Timothy, Vijayakumar, Siva, Suchy, Fabian, Nishimura, Toshinobu, Bhadury, Joydeep, Porteus, Matthew, Nakauchi, Hiromitsu, Cheung, Christine, George, Steven, Red-Horse, Kristy, Prescott, Joseph, Loh, Kyle, Ang, Lay, and Nguyen, Alana
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Hendra virus ,Nipah virus ,artery ,biosafety-level-4 virology ,developmental biology ,endothelial cells ,human pluripotent stem cells ,vein ,Arteries ,Endothelial Cells ,Hendra Virus ,Humans ,Nipah Virus ,Pluripotent Stem Cells ,Tropism - Abstract
Stem cell research endeavors to generate specific subtypes of classically defined cell types. Here, we generate >90% pure human artery or vein endothelial cells from pluripotent stem cells within 3-4 days. We specified artery cells by inhibiting vein-specifying signals and vice versa. These cells modeled viral infection of human vasculature by Nipah and Hendra viruses, which are extraordinarily deadly (∼57%-59% fatality rate) and require biosafety-level-4 containment. Generating pure populations of artery and vein cells highlighted that Nipah and Hendra viruses preferentially infected arteries; arteries expressed higher levels of their viral-entry receptor. Virally infected artery cells fused into syncytia containing up to 23 nuclei, which rapidly died. Despite infecting arteries and occupying ∼6%-17% of their transcriptome, Nipah and Hendra largely eluded innate immune detection, minimally eliciting interferon signaling. We thus efficiently generate artery and vein cells, introduce stem-cell-based toolkits for biosafety-level-4 virology, and explore the arterial tropism and cellular effects of Nipah and Hendra viruses.
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- 2022
216. Media exposure, risk perceptions, and fear: Americans’ behavioral responses to the Ebola public health crisis
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Garfin, Dana Rose, Holman, E Alison, Fischhoff, Baruch, Wong-Parodi, Gabrielle, and Silver, Roxane Cohen
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Development Studies ,Human Geography ,Human Society ,Behavioral and Social Science ,Prevention ,Vaccine Related ,Clinical Research ,Basic Behavioral and Social Science ,Emerging Infectious Diseases ,Good Health and Well Being ,Ebola virus ,Media ,Risk perceptions ,Health protective behaviors ,Public health crisis ,Environmental Science and Management ,Public Health and Health Services ,Development studies ,Human geography - Abstract
We examined media exposure, psychological fear and worry, perceptions of risk, and health protective behaviors surrounding the 2014 Ebola virus outbreak in a probability-based, representative, national sample of Americans (N = 3447). Structural equation models examined relationships between amount (hours/day) and content (e.g., graphic images of dead bodies) of media exposure and counts of self-reported health protective behaviors that participants performed or would perform if Ebola spread to their community. Ebola-related risk perceptions and fear and worry were potential mediators. Greater total hours and more graphic media exposure positively correlated with more fear and worry; greater total hours of media exposure also positively correlated with higher perceived risk. Higher risk perceptions were associated with more health protective behaviors performed and intended. Greater fear and worry were associated with more behaviors performed. Amount and content of media exposure exhibited indirect effects on behaviors performed; amount of media exposure had indirect effects on intentions. Media may help promote health protective behaviors during public health threats; the amount and content should be congruent with threat to minimize distress and maximize resources.
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- 2022
217. Association Between Repeated Exposure to Hurricanes and Mental Health in a Representative Sample of Florida Residents
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Garfin, Dana Rose, Thompson, Rebecca R, Holman, E Alison, Wong-Parodi, Gabrielle, and Silver, Roxane Cohen
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Public Health ,Health Sciences ,Climate-Related Exposures and Conditions ,Behavioral and Social Science ,Mental Health ,Brain Disorders ,Clinical Research ,2.3 Psychological ,social and economic factors ,Aetiology ,Good Health and Well Being ,Cyclonic Storms ,Female ,Florida ,Humans ,Mental Disorders ,Middle Aged ,Surveys and Questionnaires ,Biomedical and clinical sciences ,Health sciences - Abstract
ImportanceDuring the past century, more than 100 catastrophic hurricanes have impacted the Florida coast; climate change will likely be associated with increases in the intensity of future storms. Despite these annual threats to residents, to our knowledge, no longitudinal studies of representative samples at risk of hurricane exposure have examined psychological outcomes associated with repeated exposure.ObjectiveTo assess psychosocial and mental health outcomes and functional impairment associated with repeated hurricane exposure.Design, setting, and participantsIn this survey study, a demographically representative sample of Florida residents was assessed in the 60 hours prior to Hurricane Irma (wave 1: September 8-11, 2017). A second survey was administered 1 month after Hurricane Irma (wave 2: October 12-29, 2017), and a third survey was administered after Hurricane Michael (wave 3: October 22 to November 6, 2018). Data were analyzed from July 19 to 23, 2021.ExposureHurricanes Irma and Michael.Main outcomes and measuresThe main outcomes were posttraumatic stress symptoms (PTSS), global distress, worry about future events (generalized worries), and functional impairment. Path models were used to assess associations of individual-level factors (prior mental health, recent adversity), prior storm exposures (loss and/or injury, evacuation), and direct, indirect, and media-based exposures to hurricanes Irma and Michael with those outcomes. Poststratification weights were applied to facilitate population-based inferences.ResultsOf 2873 individuals administered the survey in wave 1, 1637 responded (57.0% completion rate) (894 [54.6%, weighted] women; mean [SD] age, 51.31 [17.50] years); 1478 in wave 2 (90.3% retention from wave 1) and 1113 in wave 3 (75.3% retention from wave 2) responded. Prior mental health ailments (b, 0.18; 95% CI, 0.07-0.28), prior hurricane-related loss and/or injury (b, 0.09; 95% CI, 0.02-0.17), hours of Hurricane Irma-related media exposure (b, 0.03; 95% CI, 0.02-0.04), being in an evacuation zone during Hurricane Irma and not evacuating (b, 0.14; 95% CI, 0.02-0.27), and loss and/or injury in Hurricane Irma (b, 0.35; 95% CI, 0.25-0.44) were positively associated with PTSS after Hurricane Irma; most associations persisted and were associated with responses to Hurricane Michael. Prior mental health ailments (b, 0.10; 95% CI, 0.03-0.17), hours of Hurricane Michael-related media exposure (b, 0.01; 95% CI, 0.003-0.02), hurricane Irma-related PTSS (b, 0.42; 95% CI, 0.34-0.50), recent individual-level adversity (b, 0.03; 95% CI, 0.005-0.05), being in an evacuation zone during Hurricane Irma and evacuating (b, 0.10; 95% CI, 0.002-0.19), and direct (b, 0.36; 95% CI, 0.16-0.55) and indirect (b, 0.12; 95% CI, 0.05-0.18) Hurricane Michael-related exposures were directly associated with Hurricane Michael-related PTSS. After Hurricane Michael, prior mental health ailments (b, 0.17; 95% CI, 0.06-0.28), and PTSS related to hurricanes Irma (b, 0.11; 95% CI, 0.001-0.22) and Michael (b, 0.58; 95% CI, 0.47-0.69) were associated with respondents' functional impairment. Analogous analyses using global distress and generalized worries as mediators of functional impairment yielded a similar pattern of results.Conclusions and relevanceIn this survey study, repeated direct, indirect, and media-based exposures to hurricanes were associated with increased mental health symptoms among Florida residents who experienced hurricanes Irma and Michael, suggesting that people were sensitized to respond with more psychological symptoms over time. These results may inform targeted public health intervention efforts for natural disasters.
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- 2022
218. The Role of Behavioral Medicine in Addressing Climate Change-Related Health Inequities.
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Nogueira, Leticia, White, Kristi E, Bell, Brooke, Alegria, Katie E, Bennett, Gary, Edmondson, Donald, Epel, Elissa, Holman, E Alison, Kronish, Ian M, and Thayer, Julian
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Humans ,Behavioral Medicine ,Public Health ,Climate Change ,Health Equity ,Health Inequities ,Climate change ,Environmental justice ,Health inequities ,Structural racism ,Climate-Related Exposures and Conditions ,Generic health relevance ,Climate Action ,Good Health and Well Being ,Clinical Sciences ,Oncology and Carcinogenesis - Abstract
Climate change is the greatest threat to global health in human history. It has been declared a public health emergency by the World Health Organization and leading researchers from academic institutions around the globe. Structural racism disproportionately exposes communities targeted for marginalization to the harmful consequences of climate change through greater risk of exposure and sensitivity to climate hazards and less adaptive capacity to the health threats of climate change. Given its interdisciplinary approach to integrating behavioral, psychosocial, and biomedical knowledge, the discipline of behavioral medicine is uniquely qualified to address the systemic causes of climate change-related health inequities and can offer a perspective that is currently missing from many climate and health equity efforts. In this article, we summarize relevant concepts, describe how climate change and structural racism intersect to exacerbate health inequities, and recommend six strategies with the greatest potential for addressing climate-related health inequities.
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- 2022
219. Autonomous Infrared Absorption Spectroscopy
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Holman, Hoi-Ying, primary, Lee, Steven, additional, Chen, Liang, additional, Zwart, Petrus H., additional, and Noack, Marcus M., additional
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- 2023
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220. Twenty Years Facilitating Professional Learning Communities Across Difference
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Peters, Gregory, primary, Holman, RoLesia, additional, and Bocala, Candice, additional
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- 2023
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221. The Representation of Play in Joe Simpson’s Touching the Void and Paratexts
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Holman, Anna, primary
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- 2023
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222. Revealing unforeseen diagnostic image features with deep learning by detecting cardiovascular diseases from apical four-chamber ultrasounds
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Cheng, Li-Hsin, Bosch, Pablo B. J., Hofman, Rutger F. H., Brakenhoff, Timo B., Bruggemans, Eline F., van der Geest, Rob J., and Holman, Eduard R.
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Electrical Engineering and Systems Science - Image and Video Processing ,Computer Science - Artificial Intelligence ,Computer Science - Computer Vision and Pattern Recognition ,Physics - Medical Physics - Abstract
Background. With the rise of highly portable, wireless, and low-cost ultrasound devices and automatic ultrasound acquisition techniques, an automated interpretation method requiring only a limited set of views as input could make preliminary cardiovascular disease diagnoses more accessible. In this study, we developed a deep learning (DL) method for automated detection of impaired left ventricular (LV) function and aortic valve (AV) regurgitation from apical four-chamber (A4C) ultrasound cineloops and investigated which anatomical structures or temporal frames provided the most relevant information for the DL model to enable disease classification. Methods and Results. A4C ultrasounds were extracted from 3,554 echocardiograms of patients with either impaired LV function (n=928), AV regurgitation (n=738), or no significant abnormalities (n=1,888). Two convolutional neural networks (CNNs) were trained separately to classify the respective disease cases against normal cases. The overall classification accuracy of the impaired LV function detection model was 86%, and that of the AV regurgitation detection model was 83%. Feature importance analyses demonstrated that the LV myocardium and mitral valve were important for detecting impaired LV function, while the tip of the mitral valve anterior leaflet, during opening, was considered important for detecting AV regurgitation. Conclusion. The proposed method demonstrated the feasibility of a 3D CNN approach in detection of impaired LV function and AV regurgitation using A4C ultrasound cineloops. The current research shows that DL methods can exploit large training data to detect diseases in a different way than conventionally agreed upon methods, and potentially reveal unforeseen diagnostic image features.
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- 2021
223. Could mass eccentricity explain the formation of orbits in wind turbines?
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Sander, Aljoscha, Holman, Bas, and Haselsteiner, Andreas
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Physics - Atmospheric and Oceanic Physics ,Physics - Applied Physics ,Physics - Classical Physics - Abstract
The kinematics of offshore wind turbines are of great importance when installing the turbines, as the motions of the components during craning operations are a limiting factor. Most critical is the installation of the blades: the blade's bolts need to be inserted into the rotor flange, an operation that requires great precision. Both the blade and the turbine undergo environmental loading, leading to relative motions between the blade root and the hub during installation. Results from an offshore wind farm installation measurement campaign showed, that the partially installed turbines show intricate patterns of motion (orbits) in the horizontal plane. The mechanism behind the formation of these orbits remains elusive so far. In this paper, we present a novel torsional coupling mechanism linking motions in the fore-aft and side-side direction. It can explain the formation of orbits that change direction.
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- 2021
224. The Parallel Reversible Pebbling Game: Analyzing the Post-Quantum Security of iMHFs
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Blocki, Jeremiah, Holman, Blake, and Lee, Seunghoon
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Quantum Physics ,Computer Science - Computational Complexity ,Computer Science - Cryptography and Security - Abstract
The classical (parallel) black pebbling game is a useful abstraction which allows us to analyze the resources (space, space-time, cumulative space) necessary to evaluate a function $f$ with a static data-dependency graph $G$. Of particular interest in the field of cryptography are data-independent memory-hard functions $f_{G,H}$ which are defined by a directed acyclic graph (DAG) $G$ and a cryptographic hash function $H$. The pebbling complexity of the graph $G$ characterizes the amortized cost of evaluating $f_{G,H}$ multiple times as well as the total cost to run a brute-force preimage attack over a fixed domain $\mathcal{X}$, i.e., given $y \in \{0,1\}^*$ find $x \in \mathcal{X}$ such that $f_{G,H}(x)=y$. While a classical attacker will need to evaluate the function $f_{G,H}$ at least $m=|\mathcal{X}|$ times a quantum attacker running Grover's algorithm only requires $\mathcal{O}(\sqrt{m})$ blackbox calls to a quantum circuit $C_{G,H}$ evaluating the function $f_{G,H}$. Thus, to analyze the cost of a quantum attack it is crucial to understand the space-time cost (equivalently width times depth) of the quantum circuit $C_{G,H}$. We first observe that a legal black pebbling strategy for the graph $G$ does not necessarily imply the existence of a quantum circuit with comparable complexity -- in contrast to the classical setting where any efficient pebbling strategy for $G$ corresponds to an algorithm with comparable complexity evaluating $f_{G,H}$. Motivated by this observation we introduce a new parallel reversible pebbling game which captures additional restrictions imposed by the No-Deletion Theorem in Quantum Computing. We apply our new reversible pebbling game to analyze the reversible space-time complexity of several important graphs: Line Graphs, Argon2i-A, Argon2i-B, and DRSample. (See the paper for the full abstract.), Comment: 42 pages, 5 figures
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- 2021
225. The TESS Mission Target Selection Procedure
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Fausnaugh, Michael, Morgan, Ed, Vanderspek, Roland, Pepper, Joshua, Burke, Christopher J., Levine, Alan M., Rudat, Alexander, Villaseñor, Jesus Noel S., Vezie, Michael, Goeke, Robert F., Ricker, George R., Latham, David W., Seager, S., Winn, Joshua N., Jenkins, Jon M., Bakos, G. A., Barclay, Thomas, Berta-thompson, Zachory K., Bouma, Luke G., Boyd, Patricia T., Brasseur, C. E., Burt, Jennifer, Caldwell, Douglas A., Charbonneau, David, Christensen-dalsgaard, J., Clampin, Mark, Collins, Karen A., Colón, Knicole D., De Lee, Nathan, Dunham, Edward, Fleming, Scott W., Fong, William, Soto, Aylin Garcia, Gaudi, B. Scott, Guerrero, Natalia M., Hesse, Katharine, Holman, Matthew J., Huang, Chelsea X., Kaltenegger, Lisa, Lissauer, Jack J., Mcdermott, Scott, Mclean, Brian, Mireles, Ismael, Mullally, Susan E., Oelkers, Ryan J., Paegert, Martin, Pal, Andras, Quintana, Elisa V., Rinehart, S. A., Rodriguez, David R., Rose, Mark, Sasselov, Dimitar D., Schlieder, Joshua E., Sha, Lizhou, Shporer, Avi, Smith, Jeffrey C., Stassun, Keivan G., Tenenbaum, Peter, Ting, Eric B., Torres, Guillermo, Twicken, Joseph D., Vanderburg, Andrew, Wohler, Bill, and Yu, Liang
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We describe the target selection procedure by which stars are selected for 2-minute and 20-second observations by TESS. We first list the technical requirements of the TESS instrument and ground systems processing that limit the total number of target slots. We then describe algorithms used by the TESS Payload Operation Center (POC) to merge candidate targets requested by the various TESS mission elements (the Target Selection Working Group, TESS Asteroseismic Science Consortium, and Guest Investigator office). Lastly, we summarize the properties of the observed TESS targets over the two-year primary TESS mission. We find that the POC target selection algorithm results in 2.1 to 3.4 times as many observed targets as target slots allocated for each mission element. We also find that the sky distribution of observed targets is different from the sky distributions of candidate targets due to technical constraints that require a relatively even distribution of targets across the TESS fields of view. We caution researchers exploring statistical analyses of TESS planet-host stars that the population of observed targets cannot be characterized by any simple set of criteria applied to the properties of the input Candidate Target Lists., Comment: 15 pages, 6 figures, accepted for publication in PASP
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- 2021
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226. Teaching Monte Carlo Simulation with Python
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Holman, Justin O. and Hacherl, Allie
- Abstract
It has become increasingly important for future business professionals to understand statistical computing methods as data science has gained widespread use in contemporary organizational decision processes in recent years. Used by scores of academics and practitioners in a variety of fields, Monte Carlo simulation is one of the most broadly applicable statistical computing methods. This article describes efforts to teach Monte Carlo simulation using Python. A series of simulation assignments are completed first in Google Sheets, as described in a previous article. Then, the same simulation assignments are completed in Python, as detailed in this article. This pedagogical strategy appears to support student learning for those who are unfamiliar with statistical computing but familiar with the use of spreadsheets. Supplementary materials for this article are available online.
- Published
- 2023
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227. Toward Equity in School-Based Assessment: Incorporating Collaborative/Therapeutic Techniques to Redistribute Power
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Holman, Alea R., D'Costa, Stephanie, and Janowitch, Laura
- Abstract
Psychoeducational assessment has been used as a tool to sort children into academic tracks based on children's presumed capabilities. Historically, such tracking was based on measures that sought to legitimize racist assumptions about the capabilities of children of color. Despite legal mandates and changes to practice intended to correct these injustices, children of color continue to be disproportionately sorted into less rigorous academic tracks largely based on assessment results. This article draws from the collaborative/therapeutic assessment model to propose how these techniques can increase equity and fairness in school-based assessments through shared power in the assessment relationship. We assert that a collaborative/therapeutic approach can contribute to children's and families' positive experience of assessment, and we encourage further research on these techniques to determine how they may contribute to more equitable school outcomes. We conclude with a rationale for how these techniques advance the goals of school psychology.
- Published
- 2023
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228. 'I Share to Help Them See': A Mixed-Method Analysis of Faculty Use of Self-Disclosure in Diversity Courses
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Holman, Elizabeth Grace, Paceley, Megan S., and Courts, C. L. Dominique
- Abstract
Social work education promotes a critical lens through which students engage with power systems. As educators, faculty often decide whether to share their own identities with students, yet we lack research on reasons faculty choose to share (or not share) their identities, and the ways in which privilege and marginalization affect that decision. Using a mixed-method approach, this study (N=84) addresses that gap. Quantitative analysis revealed that age was associated with intentionally sharing that identity; no other social identity was significantly related to disclosure practices. Qualitative analysis revealed the nuanced reasons that faculty elected to disclose or not disclose their identities. Discussion of these findings is situated in critical pedagogy, examining how faculty address power structures in the classroom.
- Published
- 2023
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229. Cognitive reappraisal both buffers and mediates the negative effect of childhood emotional neglect on adult resilience: Findings from a Romanian sample
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Holman, Andrei Corneliu and Jignea, Ana
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Child abuse -- Psychological aspects ,Resilience (Personality trait) -- Social aspects ,Cognitive appraisal -- Social aspects ,Psychology and mental health - Abstract
Author(s): Andrei Corneliu Holman [sup.1] , Ana Jignea [sup.1] Author Affiliations: (1) grid.8168.7, 0000000419371784, Department of Psychology, Faculty of Psychology and Education Sciences, Alexandru Ioan Cuza University of Iasi, , [...]
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- 2023
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230. Moral in the future, better now: Moral licensing versus behavioral priming in children and the moderating role of psychological distance
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Maftei, Alexandra and Holman, Andrei-Corneliu
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Child psychology -- Research ,Priming (Psychology) -- Ethical aspects ,Psychological research ,Morality -- Psychological aspects ,Pediatric research ,Psychology and mental health - Abstract
The moral licensing literature suggests that representing oneself as moral in the past or the future motivates current immoral behavior. These licensing effects are moderated by psychological distance, which depends, among others, on the concrete vs. abstract nature of the self-representations and temporal distance. Across two studies, we explored these relationships measuring children's altruism using two prospective moral licensing manipulations that varied on one of these dimensions of psychological distance (i.e., the concreteness of the moral primes) while holding temporal distance constant at its upper end (i.e., distant future). Results revealed higher altruism after imagining distant moral behaviors, contrary to the previous findings in other samples (i.e., adults), but only when concrete primes were used. This suggests that behavioral priming instead of moral licensing is the dominant effect in children in these circumstances due to their lower abstraction abilities., Author(s): Alexandra Maftei [sup.1] , Andrei-Corneliu Holman [sup.1] Author Affiliations: (1) grid.8168.7, 0000000419371784, Faculty of Psychology and Educational Sciences, 'Alexandru Ioan Cuza' University, , Toma Cozma 3, 700554, Iasi, Romania [...]
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- 2023
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231. Diabetes prevention programme put to the test
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Gregg, Edward W. and Holman, Naomi
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- 2023
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232. Population pharmacokinetics of molnupiravir in adults with COVID‐19: Lack of clinically important exposure variation across individuals
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Sébastien Bihorel, Youfang Cao, Akshita Chawla, Ruthie Birger, Brian M. Maas, Wei Gao, Stefan Roepcke, Susanne Sardella, Rebecca Humphrey, Sindhuri Kondragunta, Bhuvana Jayaraman, Monika Martinho, Wendy Painter, George Painter, Wayne Holman, Carisa De Anda, Michelle L. Brown, Matthew G. Johnson, Amanda Paschke, Matthew L. Rizk, and Julie A. Stone
- Subjects
Therapeutics. Pharmacology ,RM1-950 - Abstract
Abstract Effective antiviral treatments for coronavirus disease 2019 (COVID‐19) are needed to reduce the morbidity and mortality associated with severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) infection, particularly in patients with risk factors for severe disease. Molnupiravir (MK‐4482, EIDD‐2801) is an orally administered, ribonucleoside prodrug of β‐D‐N4‐hydroxycytidine (NHC) with submicromolar potency against SARS‐CoV‐2. A population pharmacokinetic (PopPK) analysis for molnupiravir exposure was conducted using 4202 NHC plasma concentrations collected in 1207 individuals from a phase I trial in healthy participants, a phase IIa trial in non‐hospitalized participants with COVID‐19, a phase II trial in hospitalized participants with COVID‐19, and a phase II/III trial in non‐hospitalized participants with COVID‐19. Molnupiravir pharmacokinetics (PK) was best described by a two‐compartment model with a transit‐compartment absorption model and linear elimination. Molnupiravir apparent elimination clearance increased with body weight less‐than‐proportionally (power 0.412) and was estimated as 70.6 L/h in 80‐kg individuals with a moderate interindividual variability (43.4% coefficient of variation). Additionally, effects of sex and body mass index on apparent central volume and food status and formulation on the absorption mean transit time were identified as statistically significant descriptors of variability in these PK parameters. However, none of the identified covariate effects caused clinically relevant changes in the area under the NHC concentration versus time curve between doses, the exposure metric most closely related to clinical response. Overall, the PopPK model indicates that molnupiravir can be administered in adults without dose adjustment based on age, sex, body size, food, and mild‐to‐moderate renal or mild hepatic impairment.
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- 2023
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233. Quantification of indocyanine green near-infrared fluorescence bowel perfusion assessment in colorectal surgery
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Faber, Robin A., Tange, Floris P., Galema, Hidde A., Zwaan, Thomas C., Holman, Fabian A., Peeters, Koen C. M. J., Tanis, Pieter J., Verhoef, Cornelis, Burggraaf, Jacobus, Mieog, J. Sven D., Hutteman, Merlijn, Keereweer, Stijn, Vahrmeijer, Alexander L., van der Vorst, Joost R., and Hilling, Denise E.
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- 2023
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234. Post-trial monitoring of a randomised controlled trial of intensive glycaemic control in type 2 diabetes extended from 10 years to 24 years (UKPDS 91)
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Adler, Amanda I, Coleman, Ruth L, Leal, Jose, Whiteley, William N, Clarke, Philip, and Holman, Rury R
- Published
- 2024
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235. The analysis of lamb and beef fatty acids with a 30 m BPX70 column is comparable with a 120 m column
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Clayton, Edward H., Holman, Benjamin W.B., and Meyer, Richard G.
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- 2024
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236. Continuous direct compression of a commercially batch-manufactured tablet formulation with two different processing lines
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Lyytikäinen, Jenna, Stasiak, Pawel, Kubelka, Tomáš, Bogaerts, Ivan, Wanek, Adam, Stynen, Bart, Holman, James, Ketolainen, Jarkko, Ervasti, Tuomas, and Korhonen, Ossi
- Published
- 2024
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237. Extending intersectional multilevel analysis of individual heterogeneity and discriminatory accuracy (MAIHDA) to study individual longitudinal trajectories, with application to mental health in the UK
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Bell, Andrew, Evans, Clare, Holman, Dan, and Leckie, George
- Published
- 2024
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238. Are the cardiovascular properties of GLP-1 receptor agonists differentially modulated by sulfonylureas? Insights from post-hoc analysis of EXSCEL
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Gooding, Kim M., Stevens, Susanna, Lokhnygina, Yuliya, Giczewska, Anna, Shore, Angela C., and Holman, Rury R.
- Published
- 2024
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239. Current Knowledge on the Preparation and Benefits of Cruciferous Vegetables as Relates to In Vitro, In Vivo, and Clinical Models of Inflammatory Bowel Disease
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Alaba, Tolu E, Holman, Johanna M, Ishaq, Suzanne L, and Li, Yanyan
- Published
- 2024
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240. Regional variation in cause of death in patients with type 2 diabetes: Insights from EXSCEL
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Rao, Vishal N., Sharma, Abhinav, Stebbins, Amanda, Buse, John B., Katona, Brian G., Pagidipati, Neha J., Holman, Rury R., Hernandez, Adrian, Mentz, Robert J., and Lopes, Renato D.
- Published
- 2024
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241. Covert action : a product of US national security culture
- Author
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Holman, Tom, Dorman, Andrew Mark, and Bird, Timothy
- Abstract
Covert action is a little studied but important tool of foreign policy used, most obviously, by the United States. It has entered the popular imagination, although the reality of covert action is often far removed from the image of James Bond and Jason Bourne which Hollywood has built around the term. It has also entered the fields of international relations and legal theory; understanding covert action allows scholars to better understand the use of force in, and conduct of, foreign affairs. In particular, understanding covert action opens a route to understand the Cold War. But understanding the role covert action plays in international relations is complex; it is a subject about which little material - certainly official information - is available and, while there is a substantial academic literature, it is a field dominated by former practitioners and journalists. Their accounts suffer variously from a lack of access to official sources and an over-reliance on personal experience rather than properly sourced evidence. Their understanding of their subject matter is characterised by their backgrounds; when scholars of international relations refer to covert action, they are not necessarily referring to the same thing as scholars of international law. The purpose of this research is to examine this literature in order to understand whether covert action can be objectively identified and codified as it is currently in the literature. It analyses the historical development of the term (language), the action itself, and the organisations which conduct and control it in order to understand how covert action is constructed, and to argue that it is so tightly bound into the culture of US National Security that it is not possible to identify it as a set of activities. This research concludes that the use of covert action as a means to understand international relations and the use of force is based on a flawed premise. Absent the context of US National Security Policy as it developed between the Second World War and Cold War, covert action does not exist.
- Published
- 2022
242. Micromundos biominerales en las algas rojas
- Author
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Valdespino, Patricia M, Bautista García, Andrea, Pi-Puig, Teresa, Favoretto, Fabio, Espinosa Matías, Silvia, N. Holman, Hoi-Ying, and Blanco-Jarvio, Anidia
- Abstract
Las algas rojas coralinas (rodofitas) habitan las costas, coloreando estas regiones con una hermosa tonalidad roja o rosada, y son tan duras y afiladas que, de ser pisadas, causarían dolor al pie descalzo. Entre sus diminutas ramas, muchos organismos se desarrollan y encuentran refugio. La fotosíntesis de las algas coralinas conduce a la formación de estructuras de carbonatos con una arquitectura fascinante. Pero tanto el alga como sus microorganismos asociados (microbiota) participan en la formación de estos biominerales, que se acumulan y cementan los materiales que forman las playas y las costas. Los carbonatos son susceptibles a la química ácido-base, por lo tanto, su estabilidad estructural y su disolución dependen del pH del medio que los rodea. Por tanto, estos biominerales y los organismos marinos que los forman (como algas, corales, moluscos o equinodermos) son vulnerables a la acidificación del océano. La curiosidad por ver lo que nuestros ojos no pueden nos llevó a entender que las delicadas ramitas de las algas coralinas esconden una asombrosa fortaleza estructural donde la microestructura y la química son elementos clave, pues encontramos que minerales con una gran estabilidad estructural y térmica constituyen el cuerpo, o talo, de las algas. Hoy en día las algas rojas y verdes coralinas son modelos vivos de gran interés para la ciencia básica, para capturar carbono en estructuras estables. Así, esta área de investigación puede inspirar el desarrollo de estrategias para mitigar el cambio climático.
- Published
- 2022
243. Engineering the niche to differentiate and deploy cardiovascular cells
- Author
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Gonzalez, Gisselle, Holman, Alyssa R, Nelson, Aileena C, and Engler, Adam J
- Subjects
Medical Biotechnology ,Biomedical and Clinical Sciences ,Stem Cell Research ,Bioengineering ,Regenerative Medicine ,Biotechnology ,5.2 Cellular and gene therapies ,Cell Differentiation ,Heart ,Tissue Engineering ,Biological Sciences ,Engineering ,Technology ,Agricultural biotechnology ,Industrial biotechnology ,Medical biotechnology - Abstract
Applications for stem cells have ranged from therapeutic interventions to more conventional screening and in vitro modeling, but significant limitations to each is due to the lack of maturity from decades old monolayer protocols. While those methods remain the 'gold standard,' newer three-dimensional methods, when combined with engineered niche, stand to significantly improve cell maturity and enable new applications. Here in three parts, we first discuss past methods, and where and why we believe those methods produced suboptimal myocytes. Second, we note how newer methods are moving the field into an era of cell mechanical, electrical, and biological maturity. Finally, we highlight how these improvements will solve issues of scale and engraftment to yield clinical success. It is our conclusion that only through a combination of diverse cell populations and engineered niche will we create an engineered heart tissue with the maturity and vasculature to integrate successfully into a host.
- Published
- 2022
244. A Miniaturized Programmable Multi-Fluidic Pneumatic System for precise control of Sample Preparation Environment
- Author
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Narayanasamy, Sankar Raju, Vasireddi, Ramakrishna, and Holman, Hoi-Ying
- Subjects
Physics - Biological Physics - Abstract
High-density microfluidics is becoming an important experimental platform for studying complex biological systems such as synthetic gene regulatory networks, molecular biocomputating of engineered cells, distributing rapid point-of-care diagnosis, and monitoring pathological environment. Imaging transient bio-chemical reactions happening in these systems at a single particle or cellular level requires precise time-dependent control of sample reaction and imaging conditions at the desired fluidic momentum. In this study, we showed our novel miniaturized and programmable electronic-based pneumatic system to meet the requirement. We demonstrated its capability to control reaction parameters such as concentrations and injection rates in a liposome production system., Comment: 2 pages, 2 figures, MicroTAS 2021
- Published
- 2021
245. An Open-channel Microfluidic Membrane Device for In situ Hyperspectral mapping of enzymatic cellulose hydrolysis
- Author
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Holman, Hoi-Ying N., Zhao, Wujun, Nill, Jennifer D., Chen, Liang, Narayanasamy, Sankar Raju, and Jeoh, Tina
- Subjects
Physics - Biological Physics ,Quantitative Biology - Cell Behavior - Abstract
Synchrotron infrared hyperspectral microscopy is a label-free and non-invasive technique well suited for imaging of chemical events in situ. It can track the spatial and temporal distributions of molecules of interests in a specimen in its native state by the molecule's characteristic vibrational modes. Despite tremendous progress made in recent years, IR hyperspectral imaging of chemical events in biomaterials in liquids remains challenging because of the demanding requirements on environmental control and strong infrared absorption of water. Here we report a multi-phase capillary-driven membrane device for label-free and real-time investigation of enzymatic deconstruction of algal cellulose purified from Cladophora aegagropila., Comment: 2 pages, 3 figures, MicroTAS 2021
- Published
- 2021
246. Quantum Hotspots: Mean Fields, Open EFTs, Nonlocality and Decoherence Near Black Holes
- Author
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Burgess, C. P., Holman, R., and Kaplanek, G.
- Subjects
High Energy Physics - Theory - Abstract
Effective theories describing black hole exteriors resemble open quantum systems inasmuch as many unmeasurable degrees of freedom beyond the horizon interact with those we can see. A solvable Caldeira-Leggett type model of a quantum field that mixes with many unmeasured thermal degrees of freedom on a shared surface was proposed in arXiv:2106.09854 to provide a benchmark against which more complete black hole calculations might be compared. We here use this model to test two types of field-theoretic approximation schemes that also lend themselves to describing black hole behaviour: Open EFT techniques (as applied to the fields themselves, rather than Unruh-DeWitt detectors) and mean-field methods. Mean-field methods are of interest because the effective Hamiltonians to which they lead can be nonlocal; a possible source for the nonlocality that is sometimes entertained as being possible for black holes in the near-horizon regime. Open EFTs compute the evolution of the field state, allowing discussion of thermalization and decoherence even when these occur at such late times that perturbative methods fail (as they often do). Applying both of these methods to a solvable system identifies their domains of validity and shows how their predictions relate to more garden-variety perturbative tools., Comment: 31 pages + appendices, 1 figure
- Published
- 2021
- Full Text
- View/download PDF
247. Qubit Heating Near a Hotspot
- Author
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Kaplanek, G., Burgess, C. P., and Holman, R.
- Subjects
High Energy Physics - Theory - Abstract
Effective theories describing black hole exteriors contain many open-system features due to the large number of gapless degrees of freedom that lie beyond reach across the horizon. A simple solvable Caldeira-Leggett type model of a quantum field interacting within a small area with many unmeasured thermal degrees of freedom was recently proposed in arXiv:2106.09854 to provide a toy model of this kind of dynamics against which more complete black hole calculations might be compared. We here compute the response of a simple Unruh-DeWitt detector (or qubit) interacting with a massless quantum field $\phi$ coupled to such a hotspot. Our treatment differs from traditional treatments of Unruh-DeWitt detectors by using Open-EFT tools to reliably calculate the qubit's late-time behaviour. We use these tools to determine the efficiency with which the qubit thermalizes as a function of its proximity to the hotspot. We identify a Markovian regime in which thermalization does occur, though only for qubits closer to the hotspot than a characteristic distance scale set by the $\phi$-hotspot coupling. We compute the thermalization time, and find that it varies inversely with the $\phi$-qubit coupling strength in the standard way., Comment: 16 pages + appendices, 1 figure v2) now published in JHEP, typos fixed
- Published
- 2021
- Full Text
- View/download PDF
248. Influence Through Mixing: Hotspots as Benchmarks for Basic Black-Hole Behaviour
- Author
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Kaplanek, G., Burgess, C. P., and Holman, R.
- Subjects
High Energy Physics - Theory - Abstract
Effective theories are being developed for fields outside black holes, often with an unusual open-system feel due to the influence of large number of degrees of freedom that lie out of reach beyond the horizon. What is often difficult when interpreting such theories is the absence of comparisons to simpler systems that share these features. We propose here such a simple model, involving a single external scalar field that mixes in a limited region of space with a `hotspot' containing a large number of hot internal degrees of freedom. Since the model is at heart gaussian it can be solved explicitly, and we do so for the mode functions and correlation functions for the external field once the hotspot fields are traced out. We compare with calculations that work perturbatively in the mixing parameter, and by doing so can precisely identify its domain of validity. We also show how renormalization-group EFT methods can allow some perturbative contributions to be resummed beyond leading order, verifying the result using the exact expression., Comment: 29 pages + appendices, 6 figures v2) now published in JHEP, typos fixed
- Published
- 2021
- Full Text
- View/download PDF
249. Does Strong Holiday Shopping Mean a Better Economy Ahead?
- Author
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Holman, Jordyn
- Subjects
Retail industry -- Industry sales and revenue -- Economic aspects ,Consumer spending -- Forecasts and trends ,United States economic conditions -- Forecasts and trends ,Christmas business -- Economic aspects ,Market trend/market analysis ,General interest ,News, opinion and commentary - Abstract
Consumers spent more than expected over the holidays on clothes and electronics. But the retail economy is still a mixed bag. The retail industry's report card for the critical holiday [...]
- Published
- 2025
250. Does a Strong Holiday Shopping Season Mean a Better Year Ahead?
- Author
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Holman, Jordyn
- Subjects
Retail industry -- Reports ,Consumer spending -- Reports ,Christmas business -- Reports ,News, opinion and commentary - Abstract
Consumers spent more than expected over the holidays on clothes and electronics. But the retail economy is still a mixed bag. The retail industry’s report card for the critical holiday [...]
- Published
- 2025
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