570 results on '"Kevin Walsh"'
Search Results
2. Utilization of a Novel Scoring System in Predicting 30-day Mortality in Acute Pulmonary Embolism, the CLOT-5 Pilot Study
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Alexandru Marginean MD, Punit Arora MD, Kevin Walsh MD, Elizabeth Bruno MD, Cathryn Sawalski DO, MBA, Riya Gupta MD, Frances Greathouse MD, Jacob Clarke MD, Quinn Mallery MD, Myoung Hyun Choi MD, Waddah Malas MD, Parth Shah DO, David Sutherland MD, Amudha Kumar MD, Igor Wroblewski MD, Ahmed Elkaryoni MD, Parth Desai MD, MSc, Yevgeniy Brailovsky DO, MSc, and Amir Darki MD, MSc
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Objectives To construct a new scoring system utilizing biomarkers, vitals, and imaging data to predict 30-day mortality in acute pulmonary embolism (PE). Background Acute PE, a well-known manifestation of venous thromboembolic disease, is responsible for over 100,000 deaths worldwide yearly. Contemporary management algorithms rely on a multidisciplinary approach to care via PE response teams (PERT) in the identification of low, intermediate, and high-risk patients. The PESI and sPESI scores have been used as cornerstones of the triage process in assigning risk of 30-day mortality for patients presenting with acute PE; however, the specificity of these scoring systems has often come into question. Methods This study retrospectively analyzed 488 patients with acute PE who were managed at a tertiary care institution with either conservative therapy consisting of low molecular weight or unfractionated heparin, advanced therapies consisting of catheter directed therapies, aspiration thrombectomy, or a combination of these therapies, or surgical embolectomy. The CLOT-5 score was designed to include vital signs, biomarkers, and imaging data to predict 30-day mortality in patients presenting with acute PE. Results The CLOT-5 score had an area under the curve (AUC) of 0.901 with a standard error of 0.29, while the PESI and sPESI scores had an AUC and standard errors of 0.793 ± 0.43 and 0.728 ± 0.55, respectively. Conclusions When incorporated into the management algorithms of national PERT programs, the CLOT-5 score may allow for rapid and comprehensive assessment of patients with acute PE at high risk for clinical decompensation, leading to early escalation of care where appropriate.
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- 2024
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3. I-GLAD: a new strategy for fabricating antibacterial surfaces
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Chuang Qu, Jesse Rozsa, Mark Running, Shamus McNamara, and Kevin Walsh
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I-GLAD ,Glancing angle deposition ,Antibacterial ,Gram-negative ,Gram-positive ,Nanofabrication ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract The paper uses inverted glancing angle deposition (I-GLAD) for creating antibacterial surfaces. Antibacterial surfaces are found in nature, such as on insect wings, eyes, and plant leaves. Since the bactericidal mechanism is purely physical for these surfaces, the antimicrobial resistance of bacteria to traditional chemical antibiotics can be overcome. The technical problem is how to mimic, synthesize, and scale up the naturally occurring antibacterial surfaces for practical applications, given the fact that most of those surfaces are composed of three-dimensional hierarchical micro-nano structures. This paper proposes to use I-GLAD as a novel bottom-up nanofabrication technique to scale up bio-inspired nano-structured antibacterial surfaces. Our innovative I-GLAD nanofabrication technique includes traditional GLAD deposition processes alongside the crucial inverting process. Following fabrication, we explore the antibacterial efficacy of I-GLAD surfaces using two types of bacteria: Escherichia coli (E. coli), a gram-negative bacterium, and Staphylococcus aureus (S. aureus), a gram-positive bacterium. Scanning electron microscopy (SEM) shows the small tips and flexible D/P (feature size over period) ratio of I-GLAD nanoneedles, which is required to achieve the desired bactericidal mechanism. Antibacterial properties of the I-GLAD samples are validated by achieving flat growth curves of E. coli and S. aureus, and direct observation under SEM. The paper bridges the knowledge gaps of seeding techniques for GLAD, and the control/optimization of the I-GLAD process to tune the morphologies of the nano-protrusions. I-GLAD surfaces are effective against both gram-negative and gram-positive bacteria, and they have tremendous potentials in hospital settings and daily surfaces.
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- 2024
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4. Prior probability cues bias sensory encoding with increasing task exposure
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Kevin Walsh, David P McGovern, Jessica Dully, Simon P Kelly, and Redmond G O'Connell
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expectation ,sensory processing ,perceptual decision-making ,predictive processing ,EEG ,SSVEP ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
When observers have prior knowledge about the likely outcome of their perceptual decisions, they exhibit robust behavioural biases in reaction time and choice accuracy. Computational modelling typically attributes these effects to strategic adjustments in the criterion amount of evidence required to commit to a choice alternative - usually implemented by a starting point shift - but recent work suggests that expectations may also fundamentally bias the encoding of the sensory evidence itself. Here, we recorded neural activity with EEG while participants performed a contrast discrimination task with valid, invalid, or neutral probabilistic cues across multiple testing sessions. We measured sensory evidence encoding via contrast-dependent steady-state visual-evoked potentials (SSVEP), while a read-out of criterion adjustments was provided by effector-selective mu-beta band activity over motor cortex. In keeping with prior modelling and neural recording studies, cues evoked substantial biases in motor preparation consistent with criterion adjustments, but we additionally found that the cues produced a significant modulation of the SSVEP during evidence presentation. While motor preparation adjustments were observed in the earliest trials, the sensory-level effects only emerged with extended task exposure. Our results suggest that, in addition to strategic adjustments to the decision process, probabilistic information can also induce subtle biases in the encoding of the evidence itself.
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- 2024
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5. Bilothorax: A Case Report and Systematic Literature Review of the Rare Entity
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Roshan Acharya, Smita Kafle, Yub Raj Sedhai, Dhan Bahadur Shrestha, Kevin Walsh, Wasif Elahi Shamsi, Suraj Gyawali, Nikita Acharya, Anthony Lukas Loschner, and Edmundo Raul Rubio
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Diseases of the respiratory system ,RC705-779 - Abstract
Background. Bilothorax is defined as the presence of bile in the pleural space. It is a rare condition, and diagnosis is confirmed with a pleural fluid-to-serum bilirubin ratio of >1. Methods. The PubMed, Embase, Google Scholar, and CINAHL databases were searched using predetermined Boolean parameters. The systematic literature review was done per PRISMA guidelines. Retrospective studies, case series, case reports, and conference abstracts were included. The patients with reported pleural fluid analyses were pooled for fluid parameter data analysis. Results. Of 838 articles identified through the inclusion criteria and removing 105 duplicates, 732 articles were screened with abstracts, and 285 were screened for full article review. After this, 123 studies qualified for further detailed review, and of these, 115 were pooled for data analysis. The mean pleural fluid and serum bilirubin levels were 72 mg/dL and 61 mg/dL, respectively, with a mean pleural fluid-to-serum bilirubin ratio of 3.47. In most cases, the bilothorax was reported as a subacute or remote complication of hepatobiliary surgery or procedure, and traumatic injury to the chest or abdomen was the second most common cause. Tube thoracostomy was the main treatment modality (73.83%), followed by serial thoracentesis. Fifty-two patients (51.30%) had associated bronchopleural fistulas. The mortality was considerable, with 18/115 (15.65%) reported death. Most of the patients with mortality had advanced hepatobiliary cancer and were noted to die of complications not related to bilothorax. Conclusion. Bilothorax should be suspected in patients presenting with pleural effusion following surgical manipulation of hepatobiliary structures or a traumatic injury to the chest. This review is registered with CRD42023438426.
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- 2024
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6. Adult congenital heart disease training in Europe: current status, disparities and potential solutions
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Michael A Gatzoulis, Mikael Dellborg, Margarita Brida, Alexandra Frogoudaki, Werner Budts, Colin J McMahon, Andreas Petropoulos, Gabriela Doros, Paul F Clift, Lina Gumbienė, Petra Jenkins, Massimo Chessa, Pier Paolo Bassareo, Mikko Jalanko, Dorte Nielsen, Magalie Ladouceur, Ina michel-Behnke, Kevin Walsh, Ruth Heying, Mette-Elise Estensen, Inga Voges, Katja Prokšelj, Jörg I Stein, Borislav Georgiev, Senka Mesihovic-Dinarevic, Gylfi Oskarsson, Tevfik Karagöz, Antonis Jossif, Inmaculada Sanchez Perez, Sílvia Alvares, Raili Tagen, Peter Olejnik, Skaiste Sendzikaite, Dimpna C Albert-Brotons, Mark Rhodes, Olli Pitkänen, and Ornella Milanesi
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Objectives This study aimed to determine the status of training of adult congenital heart disease (ACHD) cardiologists in Europe.Methods A questionnaire was sent to ACHD cardiologists from 34 European countries.Results Representatives from 31 of 34 countries (91%) responded. ACHD cardiology was recognised by the respective ministry of Health in two countries (7%) as a subspecialty. Two countries (7%) have formally recognised ACHD training programmes, 15 (48%) have informal (neither accredited nor certified) training and 14 (45%) have very limited or no programme. Twenty-five countries (81%) described training ACHD doctors ‘on the job’. The median number of ACHD centres per country was 4 (range 0–28), median number of ACHD surgical centres was 3 (0–26) and the median number of ACHD training centres was 2 (range 0–28). An established exit examination in ACHD was conducted in only one country (3%) and formal certification provided by two countries (7%). ACHD cardiologist number versus gross domestic product Pearson correlation coefficient=0.789 (p
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- 2023
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7. Innovation in regional graphics (and academic communication)
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Jen Nelles, Kevin Walsh, and Elvis Nyanzu
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regional graphics ,data visualization ,graphs ,maps ,Regional economics. Space in economics ,HT388 ,Regional planning ,HT390-395 - Abstract
This editorial explores the importance and power of regional graphics for communication in both academia and practice. This journal regularly publishes regional graphics, which feature one or a series of visualizations accompanied by short text that frames the value of the research and includes methodological points. In the relatively short life of the journal, regional graphics have generated a significant amount of engagement and regularly appear on the list of most viewed and trending articles. This collection assembles a diverse range of regional graphics to showcase the variety of ways that visualizations can be used to convey regional arguments, to raise the profile of this type of contribution to Regional Studies, Regional Science and to highlight innovations in visualizations that can also be used to enhance standard length articles and academic engagement beyond this medium.
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- 2022
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8. High resolution ancient sedimentary DNA shows that alpine plant diversity is associated with human land use and climate change
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Sandra Garcés-Pastor, Eric Coissac, Sébastien Lavergne, Christoph Schwörer, Jean-Paul Theurillat, Peter D. Heintzman, Owen S. Wangensteen, Willy Tinner, Fabian Rey, Martina Heer, Astrid Rutzer, Kevin Walsh, Youri Lammers, Antony G. Brown, Tomasz Goslar, Dilli P. Rijal, Dirk N. Karger, Loïc Pellissier, The PhyloAlps Consortium, Oliver Heiri, and Inger Greve Alsos
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Science - Abstract
Here, the authors use sedimentary DNA, pollen, fungal spores, chironomids, and microcharcoal from an alpine lake core to reconstruct vegetation across 12,000 years. They find that vegetation responded to climate in the early Holocene, followed by a shift to human activity from 6000 years onward corresponding with an increase in deforestation and agropastoralism.
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- 2022
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9. Direct N-body Simulations of Satellite Formation around Small Asteroids: Insights from DART’s Encounter with the Didymos System
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Harrison F. Agrusa, Yun Zhang, Derek C. Richardson, Petr Pravec, Matija Ćuk, Patrick Michel, Ronald-Louis Ballouz, Seth A. Jacobson, Daniel J. Scheeres, Kevin Walsh, Olivier Barnouin, R. Terik Daly, Eric Palmer, Maurizio Pajola, Alice Lucchetti, Filippo Tusberti, Joseph V. DeMartini, Fabio Ferrari, Alex J. Meyer, Sabina D. Raducan, and Paul Sánchez
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Asteroid dynamics ,Asteroid satellites ,Asteroid rotation ,Near-Earth objects ,Small Solar System bodies ,Asteroids ,Astronomy ,QB1-991 - Abstract
We explore binary asteroid formation by spin-up and rotational disruption considering the NASA DART mission's encounter with the Didymos–Dimorphos binary, which was the first small binary visited by a spacecraft. Using a suite of N -body simulations, we follow the gravitational accumulation of a satellite from meter-sized particles following a mass-shedding event from a rapidly rotating primary. The satellite’s formation is chaotic, as it undergoes a series of collisions, mergers, and close gravitational encounters with other moonlets, leading to a wide range of outcomes in terms of the satellite's mass, shape, orbit, and rotation state. We find that a Dimorphos-like satellite can form rapidly, in a matter of days, following a realistic mass-shedding event in which only ∼2%–3% of the primary's mass is shed. Satellites can form in synchronous rotation due to their formation near the Roche limit. There is a strong preference for forming prolate (elongated) satellites, although some simulations result in oblate spheroids like Dimorphos. The distribution of simulated secondary shapes is broadly consistent with other binary systems measured through radar or lightcurves. Unless Dimorphos's shape is an outlier, and considering the observational bias against lightcurve-based determination of secondary elongations for oblate bodies, we suggest there could be a significant population of oblate secondaries. If these satellites initially form with elongated shapes, a yet-unidentified pathway is needed to explain how they become oblate. Finally, we show that this chaotic formation pathway occasionally forms asteroid pairs and stable triples, including coorbital satellites and satellites in mean-motion resonances.
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- 2024
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10. Development of a legume-enriched feed for treatment of severe acute malnutrition [version 2; peer review: 2 approved]
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Kathryn Maitland, Gary Frost, Kevin Walsh, Gael Delamare de la Villenaise de Chenevarin, and Joe McGurk
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severe acute malnutrition ,undernutrition ,legume ,microbiome ,ready-to-use therapeutic food ,resistant starch ,eng ,Medicine ,Science - Abstract
Background: Outcomes in children hospitalised with severe acute malnutrition (SAM) remain poor. The current milk-based formulations focus on restoring weight-gain but fail to address modification of the integrity of the gut barrier and may exacerbate malabsorption owing to functional lactase, maltase and sucrase deficiency. We hypothesise that nutritional feeds should be designed to promote bacterial diversity and restore gastrointestinal (GI) barrier function. Methods: Our major objective was to develop a lactose-free, fermentable carbohydrate-containing alternative to traditional F75 and F100 formulae for the inpatient treatment of SAM. New target nutritional characteristics were developed and relevant food and infant food specific legislation were reviewed. Suitable certified suppliers of ingredients were identified. Processing and manufacture steps were evaluated and optimised for safety (nutritional, chemical and microbiological), and efficacy at meeting target characteristics (lactose-free, containing resistant starch 0.4-0.5% final product weight). Results: A final validated production process was developed and implemented to produce a novel food product for the inpatient treatment of SAM in children in Africa designed to reduce risk of osmotic diarrhoea and support symbiotic gut microbial populations. The final product matched the macronutrient profile of double-concentrated F100, adhered to all relevant legislation regulating infant foods, was lactose free, and contained 0.6% resistant starch. Chickpeas were selected as the source of resistant starch, since they are widely grown and eaten throughout Africa. Micronutrient content could not be matched in this ready-to-use product, so this was replaced at the point of feeding, as was fluid lost through concentration. Conclusions: The processes and product described illustrate the development steps for a novel nutritional product. The new feed product was ready for evaluation for safety and efficacy in a phase II clinical trial in Ugandan children admitted to hospital with SAM (Modifying Intestinal MicroBiome with Legume-Based feed 2: MIMBLE feed 2 (ISRCTN10309022)).
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- 2023
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11. Incidence and predictors of hospital readmission in children presenting with severe anaemia in Uganda and Malawi: a secondary analysis of TRACT trial data
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Roisin Connon, Elizabeth C. George, Peter Olupot-Olupot, Sarah Kiguli, George Chagaluka, Florence Alaroker, Robert O. Opoka, Ayub Mpoya, Kevin Walsh, Charles Engoru, Julius Nteziyaremye, Macpherson Mallewa, Neil Kennedy, Margaret Nakuya, Cate Namayanja, Eva Nabawanuka, Tonny Sennyondo, Denis Amorut, C. Williams Musika, Imelda Bates, M. Boele van Hensbroek, Jennifer A. Evans, Sophie Uyoga, Thomas N. Williams, Gary Frost, Diana M. Gibb, Kathryn Maitland, A. Sarah Walker, and on behalf of the TRACT trial group
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Severe anaemia ,Readmission ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Severe anaemia (haemoglobin
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- 2021
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12. Predictors of anticoagulation adherence in patients with acute pulmonary embolism
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Karim Merchant, Parth V. Desai, Stephen Morris, Sovik De Sirkar, Dalila Masic, Parth Shah, Nicolas Krepostman, Matthew Collins, Kevin Walsh, Nathalie Antonios, Lucas Chan, Sorcha Allen, Ahmad Manshad, Shannon Kuhrau, Alexandru Marginean, Ahmed Elkaryoni, Jawed Fareed, Yevgeniy Brailovsky, and Amir Darki
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Pulmonary embolism ,Adherence ,Anticoagulation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Anticoagulation (AC) adherence after acute pulmonary embolism (PE) is vital to prevent mortality and future recurrence of venous thromboembolism (VTE). We aimed to analyze factors affecting AC adherence after acute PE. Methods: Consecutive adult patients with CT angiography or V/Q scan confirmed acute PE were included in a single-center retrospective study from April 2016 to May 2020. Adherence data, including AC refill dates, were collected from pharmacies, and adherence measures including Continuous Measure of Medication Acquisition (CMA), Proportion of Days Covered (PDC), and Optimal Medication Adherence (OMA) were calculated per standardized formulas. Univariable and multivariable linear and logistic regression was used to analyze different variables affecting AC adherence. Results: A total of 118 out of 144 patients had sufficient follow-up data to measure adherence and were included in the final analysis. Mean age was 60 ± 15 years, with 64 (54.2%) women; 70 (59.3%) White, 26 (22%) African American, 13 (11%) Hispanic; 58 (49.2%) patients had private insurance, 48 (40.7%) Medicare, 11 (9.3%) Medicaid. Type of AC comprised of 57 (48.3%) apixaban, 17 (14.4%) rivaroxaban, 8 (6.8%) warfarin, 6 (5.1%) enoxaparin, and 30 (25.4%) patients with changing AC. In univariable regression, African American and Medicaid-insured patients had significantly lower adherence, while advancing age, apixaban usage, and 30-day follow-up clinic visit showed a higher adherence. However, in multivariable regression, African American race (PDC -0.135, p = 0.006, CI (−0.231, −0.040) | OMA Adjusted OR 0.166, p = 0.030, CI (0.033, 0.837)) and other non-White, non-Hispanic races (PDC -0.314, p = 0.009, CI (−0.548, −0.080)) were associated with lower AC adherence. Conclusion: In our study, African American and other minority race patients showed lower AC adherence after hospital admission for acute PE. Further studies are needed to address underlying contributors and improve adherence in this population.
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- 2022
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13. Prior employment as a causal mechanism within entrepreneurial ecosystems
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Kevin Walsh
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entrepreneurial ecosystems ,prior experience ,knowledge capital ,networks ,Regional economics. Space in economics ,HT388 ,Regional planning ,HT390-395 - Abstract
The entrepreneurial ecosystems literature lists numerous factors, emphasizing their interactions. However, there is limited empirical literature exploring the causal mechanisms, nor an understanding of the relative importance of these factors. This paper places the entrepreneur at the centre of the analysis by constructing a career history network of over 2100 Irish high-tech entrepreneurs. It finds that prior employment experience can be used to measure the prominence of different actors anticipated in the entrepreneurial ecosystem literature. Regional universities play an anchor role within each regional entrepreneurial ecosystem. Universities are indirectly connected to other organizations to form an integrated network that supports high-tech entrepreneurship. This approach may be used to assess and motivate interventions to support integration and anchor organization establishment that enhances regional entrepreneurial activity.
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- 2019
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14. Modifying gut integrity and microbiome in children with severe acute malnutrition using legume-based feeds (MIMBLE): A pilot trial
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Nuala Calder, Kevin Walsh, Peter Olupot-Olupot, Tonny Ssenyondo, Rita Muhindo, Ayub Mpoya, Jerusa Brignardello, Xuedan Wang, Eleanor McKay, Douglas Morrison, Elaine Holmes, Gary Frost, and Kathryn Maitland
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severe malnutrition ,African children ,nutritional feeds ,clinical trial ,gut barrier dysfunction ,short-chain fatty acid ,Medicine (General) ,R5-920 - Abstract
Summary: Case fatality among African children with severe acute malnutrition remains high. We report a 3-arm pilot trial in 58 Ugandan children, comparing feeds targeting disordered gastrointestinal function containing cowpea (CpF, n = 20) or inulin (InF, n = 20) with conventional feeds (ConF, n = 18). Baseline measurements of gut permeability (lactulose:mannitol ratio 1.19 ± SD 2.00), inflammation (fecal calprotectin 539.0 μg/g, interquartile range [IQR] 904.8), and satiety (plasma polypeptide YY 62.6 pmol/l, IQR 110.3) confirm gastrointestinal dysfunction. By day 28, no differences are observable in proportion achieving weight gain >5 g/kg/day (87%, 92%, 86%; p > 0.05), mortality (16%, 30%, 17%; p > 0.05), or edema resolution (83%, 54%, 91%; p > 0.05) among CpF, InF, and ConF. Decreased fecal bacterial richness from day 1 (abundance-based coverage estimator [ACE] 53.2) to day 7 (ACE 40.8) is observed only in ConF (p = 0.025). Bifidobacterium relative abundance increases from day 7 (5.8% ± 8.6%) to day 28 (10.9% ± 8.7%) in CpF (corrected p = 1.000). Legume-enriched feeds support aspects of gut function and the microbiome. Trial registration PACTR201805003381361.
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- 2021
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15. Presentation of Severe Rheumatic Mitral Stenosis at the Peak of the COVID-19 Pandemic and the Presumptive Treatment as Severe Coronavirus Illness
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Christopher Balfe, Cormac O'Connor, Gerard Giblin, Kevin Walsh, Ivan Casserly, David Moore, and Vincent Maher
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mitral stenosis ,rheumatic heart disease ,valvular heart disease ,Medicine - Abstract
This case report describes a young female Caucasian patient with newly presenting severe mitral stenosis at the peak of the coronavirus pandemic in the Republic of Ireland. The initial presumptive diagnosis was of severe coronavirus illness. This case report highlights the importance of keeping an open mind to alternative diagnoses and examines some of the challenges in the diagnosis and management of a rare condition in the pandemic environment. This patient gained 10 kg of weight within 6 weeks of percutaneous balloon mitral valvuloplasty, highlighting the contribution of cardiac cachexia to her low body weight and demonstrating the exceptional benefit that this treatment can offer to patients.
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- 2020
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16. Optimizing and evaluating the reconstruction of Metagenome-assembled microbial genomes
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Bhavya Papudeshi, J. Matthew Haggerty, Michael Doane, Megan M. Morris, Kevin Walsh, Douglas T. Beattie, Dnyanada Pande, Parisa Zaeri, Genivaldo G. Z. Silva, Fabiano Thompson, Robert A. Edwards, and Elizabeth A. Dinsdale
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Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Microbiome/host interactions describe characteristics that affect the host's health. Shotgun metagenomics includes sequencing a random subset of the microbiome to analyze its taxonomic and metabolic potential. Reconstruction of DNA fragments into genomes from metagenomes (called metagenome-assembled genomes) assigns unknown fragments to taxa/function and facilitates discovery of novel organisms. Genome reconstruction incorporates sequence assembly and sorting of assembled sequences into bins, characteristic of a genome. However, the microbial community composition, including taxonomic and phylogenetic diversity may influence genome reconstruction. We determine the optimal reconstruction method for four microbiome projects that had variable sequencing platforms (IonTorrent and Illumina), diversity (high or low), and environment (coral reefs and kelp forests), using a set of parameters to select for optimal assembly and binning tools. Methods We tested the effects of the assembly and binning processes on population genome reconstruction using 105 marine metagenomes from 4 projects. Reconstructed genomes were obtained from each project using 3 assemblers (IDBA, MetaVelvet, and SPAdes) and 2 binning tools (GroopM and MetaBat). We assessed the efficiency of assemblers using statistics that including contig continuity and contig chimerism and the effectiveness of binning tools using genome completeness and taxonomic identification. Results We concluded that SPAdes, assembled more contigs (143,718 ± 124 contigs) of longer length (N50 = 1632 ± 108 bp), and incorporated the most sequences (sequences-assembled = 19.65%). The microbial richness and evenness were maintained across the assembly, suggesting low contig chimeras. SPAdes assembly was responsive to the biological and technological variations within the project, compared with other assemblers. Among binning tools, we conclude that MetaBat produced bins with less variation in GC content (average standard deviation: 1.49), low species richness (4.91 ± 0.66), and higher genome completeness (40.92 ± 1.75) across all projects. MetaBat extracted 115 bins from the 4 projects of which 66 bins were identified as reconstructed metagenome-assembled genomes with sequences belonging to a specific genus. We identified 13 novel genomes, some of which were 100% complete, but show low similarity to genomes within databases. Conclusions In conclusion, we present a set of biologically relevant parameters for evaluation to select for optimal assembly and binning tools. For the tools we tested, SPAdes assembler and MetaBat binning tools reconstructed quality metagenome-assembled genomes for the four projects. We also conclude that metagenomes from microbial communities that have high coverage of phylogenetically distinct, and low taxonomic diversity results in highest quality metagenome-assembled genomes.
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- 2017
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17. Co-trimoxazole or multivitamin multimineral supplement for post-discharge outcomes after severe anaemia in African children: a randomised controlled trial
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Kathryn Maitland, ProfPhD, Peter Olupot-Olupot, PhD, Sarah Kiguli, MMED, George Chagaluka, MD, Florence Alaroker, MMED, Robert O Opoka, MMED, Ayub Mpoya, MSc, Kevin Walsh, MRes, Charles Engoru, MMED, Julius Nteziyaremye, MBChB, Machpherson Mallewa, PhD, Neil Kennedy, MD, Margaret Nakuya, MBChB, Cate Namayanja, MBChB, Julianne Kayaga, MBChB, Eva Nabawanuka, MBChB, Tonny Sennyondo, EGN, Denis Aromut, BSc, Felistas Kumwenda, MSc, Cynthia Williams Musika, BSc, Margaret J Thomason, PhD, Imelda Bates, PhD, Michael Boele von Hensbroek, ProfMD, Jennifer A Evans, MD, Sophie Uyoga, PhD, Thomas N Williams, ProfPhD, Gary Frost, ProfPhD, Elizabeth C George, PhD, Diana M Gibb, ProfMD, and A Sarah Walker, ProfPhD
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Public aspects of medicine ,RA1-1270 - Abstract
Summary: Background: Severe anaemia is a leading cause of paediatric admission to hospital in Africa; post-discharge outcomes remain poor, with high 6-month mortality (8%) and re-admission (17%). We aimed to investigate post-discharge interventions that might improve outcomes. Methods: Within the two-stratum, open-label, multicentre, factorial randomised TRACT trial, children aged 2 months to 12 years with severe anaemia, defined as haemoglobin of less than 6 g/dL, at admission to hospital (three in Uganda, one in Malawi) were randomly assigned, using sequentially numbered envelopes linked to a second non-sequentially numbered set of allocations stratified by centre and severity, to enhanced nutritional supplementation with iron and folate-containing multivitamin multimineral supplements versus iron and folate alone at treatment doses (usual care), and to co-trimoxazole versus no co-trimoxazole. All interventions were administered orally and were given for 3 months after discharge from hospital. Separately reported randomisations investigated transfusion management. The primary outcome was 180-day mortality. All analyses were done in the intention-to-treat population; follow-up was 180 days. This trial is registered with the International Standard Randomised Controlled Trial registry, ISRCTN84086586, and follow-up is complete. Findings: From Sept 17, 2014, to May 15, 2017, 3983 eligible children were randomly assigned to treatment, and followed up for 180 days. 164 (4%) were lost to follow-up. 1901 (95%) of 1997 assigned multivitamin multimineral supplement, 1911 (96%) of 1986 assigned iron and folate, and 1922 (96%) of 1994 assigned co-trimoxazole started treatment. By day 180, 166 (8%) children in the multivitamin multimineral supplement group versus 169 (9%) children in the iron and folate group had died (hazard ratio [HR] 0·97, 95% CI 0·79–1·21; p=0·81) and 172 (9%) who received co-trimoxazole versus 163 (8%) who did not receive co-trimoxazole had died (HR 1·07, 95% CI 0·86–1·32; p=0·56). We found no evidence of interactions between these randomisations or with transfusion randomisations (p>0·2). By day 180, 489 (24%) children in the multivitamin multimineral supplement group versus 509 (26%) children in the iron and folate group (HR 0·95, 95% CI 0·84–1·07; p=0·40), and 500 (25%) children in the co-trimoxazole group versus 498 (25%) children in the no co-trimoxazole group (1·01, 0·89–1·15; p=0·85) had had one or more serious adverse events. Most serious adverse events were re-admissions, occurring in 692 (17%) children (175 [4%] with at least two re-admissions). Interpretation: Neither enhanced supplementation with multivitamin multimineral supplement versus iron and folate treatment or co-trimoxazole prophylaxis improved 6-month survival. High rates of hospital re-admission suggest that novel interventions are urgently required for severe anaemia, given the burden it places on overstretched health services in Africa. Funding: Medical Research Council and Department for International Development.
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- 2019
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18. Function of CSF1 and IL34 in Macrophage Homeostasis, Inflammation, and Cancer
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WeiYu Lin, Daqi Xu, Cary D. Austin, Patrick Caplazi, Kate Senger, Yonglian Sun, Surinder Jeet, Judy Young, Donnie Delarosa, Eric Suto, Zhiyu Huang, Juan Zhang, Donghong Yan, Cesar Corzo, Kai Barck, Sharmila Rajan, Carrie Looney, Vineela Gandham, Justin Lesch, Wei-Ching Liang, Elaine Mai, Hai Ngu, Navneet Ratti, Yongmei Chen, Dinah Misner, Tori Lin, Dimitry Danilenko, Paula Katavolos, Estelle Doudemont, Hirdesh Uppal, Jeffrey Eastham, Judy Mak, Patricia E. de Almeida, Katherine Bao, Azadeh Hadadianpour, Mary Keir, Richard A. D. Carano, Lauri Diehl, Min Xu, Yan Wu, Robby M. Weimer, Jason DeVoss, Wyne P. Lee, Mercedesz Balazs, Kevin Walsh, Kathila R. Alatsis, Flavius Martin, and Ali A. Zarrin
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CSF1 and Il34 inhibition ,cancer ,inflammation ,macrophage ,monocyte ,CSF1R ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Colony-stimulating factor 1 (CSF1) and interleukin 34 (IL34) signal via the CSF1 receptor to regulate macrophage differentiation. Studies in IL34- or CSF1-deficient mice have revealed that IL34 function is limited to the central nervous system and skin during development. However, the roles of IL34 and CSF1 at homeostasis or in the context of inflammatory diseases or cancer in wild-type mice have not been clarified in vivo. By neutralizing CSF1 and/or IL34 in adult mice, we identified that they play important roles in macrophage differentiation, specifically in steady-state microglia, Langerhans cells, and kidney macrophages. In several inflammatory models, neutralization of both CSF1 and IL34 contributed to maximal disease protection. However, in a myeloid cell-rich tumor model, CSF1 but not IL34 was required for tumor-associated macrophage accumulation and immune homeostasis. Analysis of human inflammatory conditions reveals IL34 upregulation that may account for the protection requirement of IL34 blockade. Furthermore, evaluation of IL34 and CSF1 blockade treatment during Listeria infection reveals no substantial safety concerns. Thus, IL34 and CSF1 play non-redundant roles in macrophage differentiation, and therapeutic intervention targeting IL34 and/or CSF1 may provide an effective treatment in macrophage-driven immune-pathologies.
- Published
- 2019
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19. Etnoarcheologia dei paesaggi alpini di alta quota nelle Alpi occidentali: un bilancio preliminare / Ethnoarchaeology of Western Alpine upland landscapes: preliminary results
- Author
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Francesco Carrer, Florence Mocci, and Kevin Walsh
- Subjects
Arts in general ,NX1-820 ,Auxiliary sciences of history - Abstract
Lo studio dell’interazione tra gruppi umani e ambiente montano è centrale nell’attuale ricerca archeologica. L’etnoarcheologia contribuisce analizzando questa interazione nei contesti moderni e contemporanei, con lo scopo di creare modelli analogici per interpretare il passato e di comprendere più a fondo le strategie umane storiche e attuali. Il progetto EthWAL (Etnoarcheologia dei paesaggi alpini di alta quota nelle Alpi occidentali), nato nel 2013, si pone come punto di riferimento per lo studio delle attività umane nelle alte quote alpine in epoca moderna e contemporanea. È un progetto multidisciplinare (unisce i metodi archeologici a quelli etnografici e storiografici, alle analisi spaziali e alle analisi dei suoli) e multiscalare (dalla piccola alla grande scala). Particolare attenzione è data alle capanne pastorali tradizionali. I risultati di questo progetto saranno utili all’archeologia e permetteranno la valorizzazione delle caratteristiche culturali dei paesaggi di alta montagna. The study of the interaction between human groups and mountain environment is crucial for archaeological research. Ethnoarchaeology contributes the analysis of this interaction in modern and contemporary contexts, aimed at creating analogical models for interpreting the past and understanding human strategies in historical and modern periods. The EthWAL project (Ethnoarchaeology of Western Alpine upland Landscapes), started in 2013, and aims to be a reference for the study of human activities in the alpine uplands during the modern and contemporary age. This is a multidisciplinary (associating archaeological methods to ethnography, historiography, spatial analysis and soil analysis) and multiscalar project (small to large scale). Specific attention is given to traditional pastoral huts. The results of this project will be useful for archaeology and contribute to the management of cultural heritage in high altitude landscapes.
- Published
- 2015
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- View/download PDF
20. Multiplatform-SfM and TLS Data Fusion for Monitoring Agricultural Terraces in Complex Topographic and Landcover Conditions
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Sara Cucchiaro, Daniel J. Fallu, He Zhang, Kevin Walsh, Kristof Van Oost, Antony G. Brown, and Paolo Tarolli
- Subjects
data fusion ,coregistration ,TLS ,SfM ,terrace ,direct georeferencing ,Science - Abstract
Agricultural terraced landscapes, which are important historical heritage sites (e.g., UNESCO or Globally Important Agricultural Heritage Systems (GIAHS) sites) are under threat from increased soil degradation due to climate change and land abandonment. Remote sensing can assist in the assessment and monitoring of such cultural ecosystem services. However, due to the limitations imposed by rugged topography and the occurrence of vegetation, the application of a single high-resolution topography (HRT) technique is challenging in these particular agricultural environments. Therefore, data fusion of HRT techniques (terrestrial laser scanning (TLS) and aerial/terrestrial structure from motion (SfM)) was tested for the first time in this context (terraces), to the best of our knowledge, to overcome specific detection problems such as the complex topographic and landcover conditions of the terrace systems. SfM–TLS data fusion methodology was trialed in order to produce very high-resolution digital terrain models (DTMs) of two agricultural terrace areas, both characterized by the presence of vegetation that covers parts of the subvertical surfaces, complex morphology, and inaccessible areas. In the unreachable areas, it was necessary to find effective solutions to carry out HRT surveys; therefore, we tested the direct georeferencing (DG) method, exploiting onboard multifrequency GNSS receivers for unmanned aerial vehicles (UAVs) and postprocessing kinematic (PPK) data. The results showed that the fusion of data based on different methods and acquisition platforms is required to obtain accurate DTMs that reflect the real surface roughness of terrace systems without gaps in data. Moreover, in inaccessible or hazardous terrains, a combination of direct and indirect georeferencing was a useful solution to reduce the substantial inconvenience and cost of ground control point (GCP) placement. We show that in order to obtain a precise data fusion in these complex conditions, it is essential to utilize a complete and specific workflow. This workflow must incorporate all data merging issues and landcover condition problems, encompassing the survey planning step, the coregistration process, and the error analysis of the outputs. The high-resolution DTMs realized can provide a starting point for land degradation process assessment of these agriculture environments and supplies useful information to stakeholders for better management and protection of such important heritage landscapes.
- Published
- 2020
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- View/download PDF
21. Modifying Intestinal Integrity and MicroBiome in Severe Malnutrition with Legume-Based Feeds (MIMBLE 2.0): protocol for a phase II refined feed and intervention trial [version 1; referees: 2 approved]
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Kevin Walsh, Nuala Calder, Peter Olupot-Olupot, Tonny Ssenyondo, William Okiror, Charles Bernard Okalebo, Rita Muhindo, Ayub Mpoya, Elaine Holmes, Julian Marchesi, Gael Delamare de la Villenaise de Chenevarin, Gary Frost, and Kathryn Maitland
- Subjects
Medicine ,Science - Abstract
Background: Changes in intestinal mucosal integrity and gut microbial balance occur in severe acute malnutrition (SAM), resulting in treatment failure and adverse clinical outcomes (gram-negative sepsis, diarrhoea and high case-fatality). Transient lactose intolerance, due to loss of intestinal brush border lactase, also complicates SAM, thus milk based feeds may not be optimal for nutritional rehabilitation. Since the gut epithelial barrier can be supported by short chain fatty acids, derived from microbiota fermentation by particular fermentable carbohydrates, we postulated that an energy-dense nutritional feed comprising of legume-based fermentable carbohydrates, incorporated with lactose-free versions of standard World Health Organization (WHO) F75/F100 nutritional feeds will enhance epithelial barrier function in malnourished children, reduce and promote resolution of diarrhoea and improve overall outcome. Methods: We will investigate in an open-label trial in 160 Ugandan children with SAM, defined by mid-upper arm circumference 5 g/kg/day), ii) de novo development of diarrhoea (>3 loose stools/day), iii) time to diarrhoea resolution (if >3 loose stools/day), and iv) time to oedema resolution (if kwashiorkor) and change in intestinal biomarkers (faecal calprotectin). Discussion: We hypothesize that, if introduced early in the management of malnutrition, such lactose-free, fermentable carbohydrate-based feeds, could safely and cheaply improve global outcome by reducing lactose intolerance-related diarrhoea, improving mucosal integrity and enhancing immunity, and limiting the risk of systemic infection and associated broad-spectrum antibiotic resistance. Registration: ISRCTN 10309022.
- Published
- 2018
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22. Aura-biomes are present in the water layer above coral reef benthic macro-organisms
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Kevin Walsh, J. Matthew Haggerty, Michael P. Doane, John J. Hansen, Megan M. Morris, Ana Paula B. Moreira, Louisi de Oliveira, Luciana Leomil, Gizele D. Garcia, Fabiano Thompson, and Elizabeth A. Dinsdale
- Subjects
Corals ,Coral reefs ,Metagenomics ,Aura-biome ,Microbial ecology ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
As coral reef habitats decline worldwide, some reefs are transitioning from coral- to algal-dominated benthos with the exact cause for this shift remaining elusive. Increases in the abundance of microbes in the water column has been correlated with an increase in coral disease and reduction in coral cover. Here we investigated how multiple reef organisms influence microbial communities in the surrounding water column. Our study consisted of a field assessment of microbial communities above replicate patches dominated by a single macro-organism. Metagenomes were constructed from 20 L of water above distinct macro-organisms, including (1) the coral Mussismilia braziliensis, (2) fleshy macroalgae (Stypopodium, Dictota and Canistrocarpus), (3) turf algae, and (4) the zoanthid Palythoa caribaeorum and were compared to the water microbes collected 3 m above the reef. Microbial genera and functional potential were annotated using MG-RAST and showed that the dominant benthic macro-organisms influence the taxa and functions of microbes in the water column surrounding them, developing a specific “aura-biome”. The coral aura-biome reflected the open water column, and was associated with Synechococcus and functions suggesting oligotrophic growth, while the fleshy macroalgae aura-biome was associated with Ruegeria, Pseudomonas, and microbial functions suggesting low oxygen conditions. The turf algae aura-biome was associated with Vibrio, Flavobacterium, and functions suggesting pathogenic activity, while zoanthids were associated with Alteromonas and functions suggesting a stressful environment. Because each benthic organism has a distinct aura-biome, a change in benthic cover will change the microbial community of the water, which may lead to either the stimulation or suppression of the recruitment of benthic organisms.
- Published
- 2017
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23. Early Multiphasic HBV Infection Initiation Kinetics Is Not Clone-Specific and Is Not Affected by Hepatitis D Virus (HDV) Infection
- Author
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Masataka Tsuge, Takuro Uchida, Kevin Walsh, Yuji Ishida, Chise Tateno, Upendra Kumar, Jeffrey S. Glenn, Christopher Koh, Theo Heller, Susan L. Uprichard, Harel Dahari, and Kazuaki Chayama
- Subjects
HBV ,HDV ,human hepatocyte chimeric mice ,viral-host interactions ,HBV/HDV co-infection ,Microbiology ,QR1-502 - Abstract
Backgrounds and Aims: We previously demonstrated that serum hepatitis B virus (HBV) DNA in HBV infected humanized mice exhibited a highly dynamic multiphasic kinetic pattern from infection initiation to steady-state. Here, we investigated whether this pattern is consistent across different HBV clones or in the presence of hepatitis D virus (HDV) co-infection. Methods: We analyzed early serum viral kinetics using 26 HBV genotype C (GtC) mono-infected mice [clones: PXB, Hiroshima GtC CL4 (CL4) and Hiroshima GtC CL5 (CL5)] and four HBV CL4/HDV genotype one co-infected mice. Results: The HBV kinetics observed with clones CL4 and CL5 were similar to that previously defined in HBV PXB infected mice. Additionally, no significant differences in HBV DNA levels were observed between HBV mono-infected and HBV/HDV co-infected mice through 4 weeks post-inoculation (p.i.). However, HBV DNA levels at 6 weeks p.i. in HBV/HDV co-infected mice were significantly lower than those in HBV mono-infected mice (P = 0.002), consistent with HDV suppression of chronic HBV. Conclusions: HBV infection initiation is multiphasic across multiple viral clones and is not altered by HDV co-infection. The latter suggests that higher HDV titers (>8 log IU/mL) and/or longer duration of HDV infection might be needed to trigger HDV-induced suppression on HBV.
- Published
- 2019
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24. Interpreting the Rock Paintings of Abri Faravel: laser and white-light scanning at 2,133m in the southern French Alps
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Kevin Walsh, Florence Mocci, Claudia Defrasne, Vincent Dumas, and Anthony Masinton
- Subjects
Rock art ,Rock painting ,Alps ,France ,Mesolithic ,Neolithic ,Bronze age ,Iron Age ,landscape ,archaeology ,virtual model ,Archaeology ,CC1-960 - Abstract
The Abri Faravel, discovered in 2010 at 2,133m asl in the Parc National des Ecrins, Freissinières, Southern French Alps, is probably the most enigmatic high altitude site in the Alps. This rock shelter saw phases of human activity from the Mesolithic through to the medieval period; the artefactual assemblages comprise Mesolithic and Neolithic flint tools, Iron Age hand-thrown pottery, a Roman fibula and some medieval metalwork. However, the most interesting and unique feature on the site are the prehistoric rock paintings; the highest representations of animals (quadrupeds) in Europe. These paintings are presented in this article. The paintings themselves were the object of a white-light scan, whilst the rock-shelter and surrounding landscape was scanned using a Faro laser scanner. Both of these models are presented here, and their interpretation elucidated by an assessment of the different phases of activity at the shelter, combined with a synthesis of other evidence from the area and pertinent environmental evidence.
- Published
- 2016
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25. Chemical Analysis of Pottery Demonstrates Prehistoric Origin for High-Altitude Alpine Dairying.
- Author
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Francesco Carrer, André Carlo Colonese, Alexandre Lucquin, Eduardo Petersen Guedes, Anu Thompson, Kevin Walsh, Thomas Reitmaier, and Oliver E Craig
- Subjects
Medicine ,Science - Abstract
The European high Alps are internationally renowned for their dairy produce, which are of huge cultural and economic significance to the region. Although the recent history of alpine dairying has been well studied, virtually nothing is known regarding the origins of this practice. This is due to poor preservation of high altitude archaeological sites and the ephemeral nature of transhumance economic practices. Archaeologists have suggested that stone structures that appear around 3,000 years ago are associated with more intense seasonal occupation of the high Alps and perhaps the establishment of new economic strategies. Here, we report on organic residue analysis of small fragments of pottery sherds that are occasionally preserved both at these sites and earlier prehistoric rock-shelters. Based mainly on isotopic criteria, dairy lipids could only be identified on ceramics from the stone structures, which date to the Iron Age (ca. 3,000-2,500 BP), providing the earliest evidence of this practice in the high Alps. Dairy production in such a marginal environment implies a high degree of risk even by today's standards. We postulate that this practice was driven by population increase and climate deterioration that put pressure on lowland agropastoral systems and the establishment of more extensive trade networks, leading to greater demand for highly nutritious and transportable dairy products.
- Published
- 2016
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26. Engineering Mountain Landscapes: An Anthropology of Social Investment
- Author
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Kevin Walsh
- Subjects
book review ,Environmental sciences ,GE1-350 - Abstract
Reviewed: Engineering Mountain Landscapes: An Anthropology of Social Investment Edited by Laura L. Scheiber and Maria Nieves Zedeño. Salt Lake City, UT: University of Utah Press, 2015. x + 201 pp. US$ 45.00. ISBN 978-1-60781-433-7.
- Published
- 2016
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- View/download PDF
27. Relative contribution of Th1 and Th17 cells in adaptive immunity to Bordetella pertussis: towards the rational design of an improved acellular pertussis vaccine.
- Author
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Pádraig J Ross, Caroline E Sutton, Sarah Higgins, Aideen C Allen, Kevin Walsh, Alicja Misiak, Ed C Lavelle, Rachel M McLoughlin, and Kingston H G Mills
- Subjects
Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Whooping cough caused by Bordetella pertussis is a re-emerging infectious disease despite the introduction of safer acellular pertussis vaccines (Pa). One explanation for this is that Pa are less protective than the more reactogenic whole cell pertussis vaccines (Pw) that they replaced. Although Pa induce potent antibody responses, and protection has been found to be associated with high concentrations of circulating IgG against vaccine antigens, it has not been firmly established that host protection induced with this vaccine is mediated solely by humoral immunity. The aim of this study was to examine the relative contribution of Th1 and Th17 cells in host immunity to infection with B. pertussis and in immunity induced by immunization with Pw and Pa and to use this information to help rationally design a more effective Pa. Our findings demonstrate that Th1 and Th17 both function in protective immunity induced by infection with B. pertussis or immunization with Pw. In contrast, a current licensed Pa, administered with alum as the adjuvant, induced Th2 and Th17 cells, but weak Th1 responses. We found that IL-1 signalling played a central role in protective immunity induced with alum-adsorbed Pa and this was associated with the induction of Th17 cells. Pa generated strong antibody and Th2 responses, but was fully protective in IL-4-defective mice, suggesting that Th2 cells were dispensable. In contrast, Pa failed to confer protective immunity in IL-17A-defective mice. Bacterial clearance mediated by Pa-induced Th17 cells was associated with cell recruitment to the lungs after challenge. Finally, protective immunity induced by an experimental Pa could be enhanced by substituting alum with a TLR agonist that induces Th1 cells. Our findings demonstrate that alum promotes protective immunity through IL-1β-induced IL-17A production, but also reveal that optimum protection against B. pertussis requires induction of Th1, but not Th2 cells.
- Published
- 2013
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28. Emergency Action Plans: Preparing for a School Crisis
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Jolene Battitori and Kevin Walsh
- Abstract
School principals are responsible for the safety and well-being of the children entrusted to their care. Parents expect their children to be safe and protected and that school leaders establish and maintain clear lines of communication during a time of crisis. Within their capacity as school leaders, it is incumbent on them to guarantee that school personnel are prepared and responsive in a manner that ensures student and staff safety. In practice, school principals and staff are often forced to assume the role as actual 'first responders' until other professional emergency responders from the community arrive. This paper highlights the importance for school principals to take a leadership role in ensuring that Emergency Action Plans (EAP) are clearly defined, communicated, reviewed, rehearsed, and revised. It focuses on Professional Standards for Educational Leaders (PSEL) 8, 9 and National Educational Leadership Preparation (NELP) National Education Leadership Preparation 5.3, 6.2, 6.3 standards.
- Published
- 2023
29. Mechanisms for Mutual Attested Microservice Communication.
- Author
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Kevin Walsh and John Manferdelli
- Published
- 2017
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30. Intra-Cloud and Inter-Cloud Authentication.
- Author
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Kevin Walsh and John Manferdelli
- Published
- 2017
- Full Text
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31. Early to Middle Bronze Age agricultural terraces in north-east England: morphology, dating and cultural implications
- Author
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Antony G. Brown, Daniel Fallu, Sara Cucchiaro, Monica Alonso-Eguiluz, Rosa Maria Albert, Kevin Walsh, Ben R. Pears, Rob Scaife, Catherine Langdon, Paolo Tarolli, David Cockroft, Lisa Snape, Andreas Lang, Philippa Ascough, Pengzhi Zhao, Kristof Van Oost, and Clive Waddington
- Subjects
Bronze Age ,Britain ,Archeology ,landscape history ,prehistoric agriculture ,pollen ,General Arts and Humanities ,pOSL ,phytoliths ,environmental archaeology - Abstract
Terracing is found widely in the Mediterranean and in other hilly and mountainous regions of the world. Yet while archaeological attention to these ‘mundane’ landscape features has grown, they remain understudied, particularly in Northern Europe. Here, the authors present a multidisciplinary study of terraces in the Breamish Valley, Northumberland. The results date their construction to the Early to Middle Bronze Age, when they were built by cutting back the hillside, stone clearance and wall construction. Environmental evidence points to their use for cereal cultivation. The authors suggest that the construction and use of these terraces formed part of an Early to Middle Bronze Age agricultural intensification, which may have been both demographically and culturally driven.
- Published
- 2023
32. Geophysical evidence that Saturn’s Moon Phoebe originated from a C-type asteroid reservoir
- Author
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Julie Castillo-Rogez, Pierre Vernazza, and Kevin Walsh
- Published
- 2019
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33. TLS with trustworthy certificate authorities.
- Author
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Kevin Walsh
- Published
- 2016
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34. Volatile-rich Asteroids in the Inner Solar System
- Author
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Joseph A. Nuth, III, Neyda Abreu, Frank T Ferguson, Daniel P Glavin, Carl Hergenrother, Hugh G. M. Hill, Natasha M. Johnson, Maurizio Pajola, and Kevin Walsh
- Subjects
Space Sciences (General) ,Exobiology - Abstract
Bennu (101195), target of the Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) mission, is a type-B asteroid with abundant spectral evidence for hydrated silicates, low thermal inertia “boulders” and frequent bursts of particle emission. We suggest that Bennu’s parent body formed in the outer solar system before it was perturbed into the asteroid belt and then evolved into a near-Earth object. We show that this is consistent with models of planetesimal evolution. Bennu has many characteristics expected for a dormant comet, and could potentially contain a minimum of 1 wt.% adsorbed water if its gross mineralogy is consistent with the Orgueil meteorite. This is in addition to any ice or water contained within the hydrous minerals themselves. Based on this hypothesis, we predict the properties of the samples that will be returned to Earth by the OSIRIS-REx mission, including abundant phyllosilicate minerals, amorphous hydrated silicates and low-density, very high-porosity aggregates, already observed by the OSIRIS-REx instrument suite. We predict enrichments in D/H and 15N/14N, high C/Mg ratios (>∼7 wt%), and a greater range of organic compositions than found in meteorites, including an organic component poor in aromatics, and a more labile organic fraction. Ammonium salts, ranging from NH4Cl to ammonium–organic acid salts could carry much of the nitrogen in comets, yet only NH4CH3COO and heavier salts are sufficiently stable to be found in these returned samples. Water adsorbed onto highly porous grains should also be detected provided that the sample return capsule remains below 300 K during Earth return, and this water should be isotopically heavy.
- Published
- 2020
- Full Text
- View/download PDF
35. Multimodality imaging in delineation of complex sinus venosus defects and treatment outcomes over the last decade
- Author
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Lars Nolke, Orla Franklin, Adam T. James, Kevin Walsh, Colin J. McMahon, Jonathan McGuinness, Li Y. Ng, J.Mark Redmond, Brian Grant, RS: SHE - R1 - Research (OvO), and Onderwijsontw & Onderwijsresearch
- Subjects
medicine.medical_specialty ,PULMONARY VENOUS CONNECTION ,Vena Cava, Superior ,Adolescent ,Vascular Malformations ,DRAINAGE ,SUPERIOR VENA-CAVA ,TRANSCATHETER CORRECTION ,ATRIAL-SEPTAL-DEFECT ,DIAGNOSIS ,Heart Septal Defects, Atrial ,Pulmonary vein ,surgery ,Humans ,Medicine ,SINGLE-PATCH ,warden procedure ,Child ,Vein ,Sinus (anatomy) ,Sinus venosus ,Anomalous pulmonary venous connection ,business.industry ,Scimitar Syndrome ,Infant ,imaging ,General Medicine ,medicine.disease ,SURGICAL REPAIR ,Venous Obstruction ,anomalous pulmonary venous drainage ,Treatment Outcome ,medicine.anatomical_structure ,Pulmonary Veins ,Echocardiography ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,CLOSURE ,cardiovascular system ,Radiology ,sinus venosus defect ,Cardiology and Cardiovascular Medicine ,business ,FOLLOW-UP ,Shunt (electrical) ,Atrial flutter - Abstract
Background:Diagnosis of sinus venosus defects, not infrequently associated with complex anomalous pulmonary venous drainage, may be delayed requiring multimodality imaging.Methods:Retrospective review of all patients from February 2008 to January 2019.Results:Thirty-seven children were diagnosed at a median age of 4.2 years (range 0.5−15.5 years). In 32 of 37 (86%) patients, diagnosis was achieved on transthoracic echocardiography, but five patients (14%) had complex variants (four had high insertion of anomalous vein into the superior caval vein and three had multiple anomalous veins draining to different sites, two of whom had drainage of one vein into the high superior caval vein). In these five patients, the final diagnosis was achieved by multimodality imaging and intra-operative findings. The median age at surgery was 5.2 years (range 1.6−15.8 years). Thirty-one patients underwent double patch repair, four patients a Warden repair, and two patients a single-patch repair. Of the four Warden repairs, two patients had a high insertion of right-sided anomalous pulmonary vein into the superior caval vein, one patient had bilateral superior caval veins, and one patient had right lower pulmonary vein insertion into the right atrium/superior caval vein junction. There was no post-operative mortality, reoperation, residual shunt or pulmonary venous obstruction. One patient developed superior caval vein obstruction and one patient developed atrial flutter.Conclusion:Complementary cardiac imaging modalities improve diagnosis of complex sinus venosus defects associated with a wide variation in the pattern of anomalous pulmonary venous connection. Nonetheless, surgical treatment is associated with excellent outcomes.
- Published
- 2022
36. Analysis of Emergency Medicine Clerkship Grades by Identification as URiM vs. non-URiM
- Author
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Kevin Walsh, Jospeh House, Laura Hopson, and Elizabeth Holman
- Subjects
Emergency Medicine ,General Medicine - Published
- 2023
37. Agricultural Terraces As DNA Archives and Implications for Terrace Archaeology
- Author
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Antony G. Brown, Andreas Lang, Daniel J. Fallu, Kevin Walsh, Francesco Ficetola, and Inger Alsos
- Abstract
Although agricultural terraces have a long history of use in the steepland areas of Europe very little is known about their use-history and its variability over space or time. This is partly because, being composed of generally inorganic well drained soil horizons, they often have poor preservation of pollen, spores and even phytoliths. The TerrACE project (ERC funded) set out to test the application of sedaDNA from terrace soils sampled from Greece to northern Norway using metabarcoding. The findings have been surprising - as the expectation was that only soils from the most northerly sites (Norway, UK) with mean annual temperatures below 10oC would provide positive results. This has proven not to be the case, with most sites providing usable data except the very warmest and driest (Crete). This also relates to the timing of agriculture with usable data from the Bronze Age throughout all periods to Late Medieval times. This reveals soil DNA of both a variety of crops, including but not exclusively cereals, and domesticated stock. However, there are, as expected, indications of both leaching and bioturbation effecting these records. These taphonomic aspects will be discussed alongside the potential of sedaDNA for tracing agricultural histories from cumulative soils.
- Published
- 2023
38. Linking enstatite meteorites to a unique source
- Author
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Chrysa Avdellidou, Marco Delbo, Alessandro Morbidelli, Kevin Walsh, Edhah Munaibari, Jules Bourdelle de Micas, Maxime Devogele, Sonia Fornasier, Matthieu Gounelle, and Gerard van Belle
- Abstract
The identification of meteorite parent bodies provides the context for understanding planetesimal formation and evolution as well as the key Solar System events they have witnessed. However, identifying such links has proven challenging and some appear ambiguous. Here, we identify that the family of asteroid fragments whose largest member is (161) Athor is the unique source of the rare EL enstatite chondrite meteorites, the closest meteorites to Earth in terms of their isotopic ratios. The Athor family was created by the collisional fragmentation of a parent body 3 Gyr ago in the inner main belt. We calculate that the diameter of the Athor family progenitor was 64 km in diameter, much smaller than the putative size of the EL original planetesimal. Therefore, we deduce that the EL planetesimal that accreted in the terrestrial planet region underwent a first catastrophic collision in that region, and one of its fragments suffered a more recent catastrophic collision in the main belt, generating the current source of the EL meteorites.
- Published
- 2023
39. Adolescent experiences of sexting: A systematic review of the qualitative literature, and recommendations for practice
- Author
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Jessica Dully, Kevin Walsh, Caoimhe Doyle, and Gary O'Reilly
- Subjects
Psychiatry and Mental health ,Social Psychology ,Pediatrics, Perinatology and Child Health ,Developmental and Educational Psychology - Published
- 2023
40. Moisture control of tropical cyclones in high-resolution simulations of paleoclimate and future climate
- Author
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Pavan Harika Raavi, Jung-Eun Chu, Axel Timmermann, Sun-Seon Lee, and Kevin Walsh
- Abstract
The intensity of tropical cyclones (TCs) is expected to increase in response to greenhouse warming. However, how future climate change will affect TC frequencies and tracks is still under debate. To further elucidate the underlying sensitivities, we study TCs response to different past and future climate forcings. Using a high-resolution TC-resolving global Earth system model with 1/4o atmosphere and 1/10o ocean resolution we conducted a series of paleo-snapshot and future greenhouse warming simulations targeting the last interglacial (Marine Isotope Stage (MIS) 5e, 125 ka), glacial sub-stage MIS5d (115 ka), present-day (PD), and CO2 doubling (2×CO2) conditions. Our analysis reveals that precessional forcing creates an interhemispheric difference in simulated TC densities, whereas future CO2 forcing impacts both hemispheres in the same direction. In both cases, we find that TC genesis frequency, density, and intensity are primarily controlled by changes in tropospheric thermal and moisture structure, with warmer hemispheres exhibiting a reduction in TC density. Teaser Precessional and CO2 effects on tropical cyclone formation are primarily controlled by moisture-related processes.
- Published
- 2023
41. Seismic zonation and default suites of ground-motion records for time-history analysis in the South Island of New Zealand
- Author
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Christianos Burlotos, Kevin Walsh, Tatiana Goded, Graeme McVerry, Nicholas Brooke, and Jason Ingham
- Subjects
Geotechnical Engineering and Engineering Geology ,Civil and Structural Engineering - Abstract
The rise of performance-based earthquake engineering, in combination with the complexity associated with selecting records for time-history analysis, demonstrates an expressed need for localized default suites of ground motion records for structural designers to use in the absence of site-specific studies. In the current research investigation, deaggregations of probabilistic seismic hazard models (National Seismic Hazard Model, Canterbury Seismic Hazard Model, and Kaikōura Seismic Hazard Model) and the location-specific seismological characteristics of expected ground motions were used to define eight seismic hazard zonations and accompanying suite profiles for the South Island of New Zealand to satisfy the requirements of the New Zealand structural design standard NZS1170.5 for response-history analyses. Specific records, including 21 from the recent Kaikōura, Darfield, and Christchurch earthquakes, were then selected from publicly-available databases and presented as default suites for use in time-history analyses in the absence of site-specific studies. This investigation encompasses seismic hazards corresponding to 500-year return periods, site classes C (shallow soils) and D (deep soils), and buildings with fundamental periods between 0.4 and 2.0 seconds.
- Published
- 2022
42. Fused Filament Fabrication of Bioresorbable Stent on a Rotating Mandrel
- Author
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Gurminder Singh, Ryan Paetzold, Fergal Coulter, Colin J. McMahon, Kevin Walsh, William Ronan, Eoin O’Cearbhaill, Ceretti, Elisabetta, and Filice, Luigino
- Subjects
3D Printing ,Grasshopper ,Stent ,Biresorbable ,General Earth and Planetary Sciences ,General Environmental Science - Abstract
Bioresorbable stents have the potential to restore patency to blood vessels while minimising the risk of long-term complications. Bioresorbable stents can dissolve after restoring flow to a blocked artery, leaving behind a blood vessel with restored vascular tone. This can provide increased lumen gain, long-term vascular rehabilitation, and long-term healing. Additive manufacturing (AM) could offer new design freedom and patient-specific solutions; however, AM fabrication of bioresorbable stents, especially for specific patients, is challenging. In recent times, AM-based Fused Filament Fabrication (FFF) has gained popularity for printing stents by employing a rotating mandrel as a printing bed. However, using standard slicing methodology is challenging when generating extrusion profiles with strut dimensions at this size scale. By eliminating the requirement for a CAD model and instead slicing based on direct extrusion path generation from parametric curves, a method has been proposed for the FFF printing of bioresorbable stents on rotating mandrels. A Grasshopper (plugin in Rhinoceros) -based visual programming method was adopted for the generation of the required shapes of curves for the stent. The extrusion profile (gCode) was generated by Grasshopper for 3D printing on an FFF multi-axis machine. Poly (l-lactic) acid (PLLA) polymer material was chosen along with a standard zigzag stent shape for testing the proposed methodology. The extrusion temperature, nozzle speed, and extrusion values were varied as per the design of the experiment (Taguchi L9) approach to study their effect on the stent strut width and flexural strength. The optimisation was carried out to obtain a feasible relationship between parameters to print minimum strut width and maximum flexural strength. The proposed methodology successfully demonstrates printing complex stent shapes without a CAD model and slicing. (C) 2022 The Authors. Published by Elsevier B.V., Procedia CIRP, 110, ISSN:2212-8271, V CIRP Conference on BioManufacturing
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- 2022
43. Climate processes and drivers in the Pacific and global warming: a review for informing Pacific planning agencies
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Savin Chand, Scott Power, Kevin Walsh, Neil Holbrook, Kathleen McInnes, Kevin Tory, Hamish Ramsay, Ron Hoeke, and Anthony S. Kiem
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Atmospheric Science ,Global and Planetary Change - Abstract
Pacific Island countries are vulnerable to climate variability and change. Developing strategies for adaptation and planning processes in the Pacific requires new knowledge and updated information on climate science. In this paper, we review key climatic processes and drivers that operate in the Pacific, how they may change in the future and what the impact of these changes might be. In particular, our emphasis is on the two major atmospheric circulation patterns, namely the Hadley and Walker circulations. We also examine climatic features such as the South Pacific Convergence Zone and Intertropical Convergence Zone, as well as factors that modulate natural climate variability on different timescales. It is anticipated that our review of the main climate processes and drivers that operate in the Pacific, as well as how these processes and drivers are likely to change in the future under anthropogenic global warming, can help relevant national agencies (such as Meteorological Services and National Disaster Management Offices) clearly communicate new information to sector-specific stakeholders and the wider community through awareness raising.
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- 2023
44. Response of Tropical Cyclone Frequency to Sea Surface Temperatures Using Aqua-Planet Simulations
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Pavan Harika Raavi and Kevin Walsh
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Mass flux ,010504 meteorology & atmospheric sciences ,tropical cyclone ,Storm ,GC1-1581 ,tropical depression ,Vorticity ,Oceanography ,010502 geochemistry & geophysics ,Atmospheric sciences ,01 natural sciences ,Vortex ,Atmosphere ,aqua-planet global climate model simulations ,13. Climate action ,Wind shear ,Environmental science ,Okubo–Weiss zeta parameter ,14. Life underwater ,Tropical cyclone ,Saturation (chemistry) ,0105 earth and related environmental sciences - Abstract
The present study investigates the effect of increasing sea surface temperatures (SSTs) on tropical cyclone (TC) frequency using the high-resolution Australian Community Climate and Earth-System Simulator (ACCESS) model. We examine environmental conditions leading to changes in TC frequency in aqua-planet global climate model simulations with globally uniform sea surface temperatures (SSTs). Two different TC tracking schemes are used. The Commonwealth Scientific and Industrial Research Organization (CSIRO) scheme (a resolution-dependent scheme) detects TCs that resemble observed storms, while the Okubo–Weiss zeta parameter (OWZP) tracking scheme (a resolution-independent scheme) detects the locations within “marsupial pouches” that are favorable for TC formation. Both schemes indicate a decrease in the global mean TC frequency with increased saturation deficit and static stability of the atmosphere. The OWZP scheme shows a poleward shift in the genesis locations with rising temperatures, due to lower vertical wind shear. We also observe an overall decrease in the formation of tropical depressions (TDs) with increased temperatures, both for those that develop into TCs and non-developing cases. The environmental variations at the time of TD genesis between the developing and the non-developing tropical depressions identify the Okubo–Weiss (OW) parameter and omega (vertical mass flux) as significant influencing variables. Initial vortices with lower vorticity or with weaker upward mass flux do not develop into TCs due to environments with higher saturation deficit and stronger static stability of the atmosphere. The latitudinal variations in the large-scale environmental conditions account for the latitudinal differences in the TC frequency in the OWZP scheme.
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- 2021
45. Environmental Reconstruction in Mediterranean Landscape Archaeology
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Philippe Leveau, Kevin Walsh, Frederic Trement
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- 2016
46. The Formation of Bilobate Comet Shapes through Sublimative Torques
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Taylor K. Safrit, Jordan K. Steckloff, Amanda S. Bosh, David Nesvorny, Kevin Walsh, Ramon Brasser, and David A. Minton
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- 2021
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47. CT-measured Cortical Volume Ratio Is an Accurate Alternative to Nuclear Medicine Split Scan Ratio Among Living Kidney Donors
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Erica B. Stein, John R. Montgomery, Allyse N. Zondlak, Kenneth J. Woodside, Emily A. Herriman, Jeremy B. Sussman, Yee Lu, Craig S. Brown, Julia E. Kozlowski, Alexa M. Pinsky, Prasad R. Shankar, Randall S. Sung, and Kevin Walsh
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Transplantation ,Kidney ,business.industry ,Kidney donation ,Renal function ,Kidney Transplantation ,Cortical volume ,Confidence interval ,Iodine Radioisotopes ,medicine.anatomical_structure ,Primary outcome ,Living Donors ,Retrospective analysis ,Humans ,Medicine ,DONOR EVALUATION ,Nuclear Medicine ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,Glomerular Filtration Rate ,Retrospective Studies - Abstract
BACKGROUND The 125I-iothalamate clearance and 99mTc diethylenetriamine-pentaacetic acid (99mTc-DTPA) split scan nuclear medicine studies are used among living kidney donor candidates to determine measured glomerular filtration rate (mGFR) and split scan ratio (SSR). The computerized tomography-derived cortical volume ratio (CVR) is a novel measurement of split kidney function and can be combined with predonation estimated GFR (eGFR) or mGFR to predict postdonation kidney function. Whether predonation SSR predicts postdonation kidney function better than predonation CVR and whether predonation mGFR provides additional information beyond predonation eGFR are unknown. METHODS We performed a single-center retrospective analysis of 204 patients who underwent kidney donation between June 2015 and March 2019. The primary outcome was 1-y postdonation eGFR. Model bases were created from a measure of predonation kidney function (mGFR or eGFR) multiplied by the proportion that each nondonated kidney contributed to predonation kidney function (SSR or CVR). Multivariable elastic net regression with 1000 repetitions was used to determine the mean and 95% confidence interval of R2, root mean square error (RMSE), and proportion overprediction ≥15 mL/min/1.73 m2 between models. RESULTS In validation cohorts, eGFR-CVR models performed best (R2, 0.547; RMSE, 9.2 mL/min/1.73 m2, proportion overprediction 3.1%), whereas mGFR-SSR models performed worst (R2, 0.360; RMSE, 10.9 mL/min/1.73 m2, proportion overprediction 7.2%) (P
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- 2021
48. Clinical utility of immediate postoperative radiographs following uncomplicated primary reverse shoulder arthroplasty
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Aakash Chauhan, Anthony A. Romeo, Marc Asselmeier, Brian Murphy, Diego Villacis, and Kevin Walsh
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medicine.medical_specialty ,medicine.medical_treatment ,Radiography ,Nonunion ,Reverse shoulder ,Osteoarthritis ,Pacu ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Orthopedics and Sports Medicine ,Postoperative Period ,Retrospective Studies ,030222 orthopedics ,biology ,Shoulder Joint ,business.industry ,Postoperative complication ,030229 sport sciences ,General Medicine ,Humerus ,medicine.disease ,biology.organism_classification ,Arthroplasty ,Surgery ,Treatment Outcome ,Arthroplasty, Replacement, Shoulder ,Cohort ,Rotator Cuff Tear Arthropathy ,business - Abstract
Background It is common practice to order an immediate postoperative radiograph in the postanesthesia care unit (PACU) following reverse shoulder arthroplasty (RSA). However, with a growing emphasis on value-based care and cost-effectiveness, we question the necessity for immediate postoperative radiographs following uncomplicated, primary RSA. Methods From 2014-2020, patients undergoing primary RSA at a single institution by one of 3 surgeons were included in this cohort. Radiographs from the PACU and any clinic visit during the initial 3-month postoperative period were reviewed to determine if any radiographic findings from the PACU altered clinical care or decision making. Results A total of 157 patients were included in this study and 13 patients had abnormal findings during the initial 3-month postoperative period where the immediate postoperative radiograph provided clinical utility for decision making. In 9 of the 12 patients requiring revision surgery, the postoperative complication was instability. In those patients requiring revision surgery during the initial 3 months, the most common indication for primary surgery was proximal humerus nonunion. Immediate postoperative radiographs were read by the radiologist as normal/unremarkable for 100% of patients. The typical amount billed for the immediate postoperative radiograph was $544.00 per patient. Conclusion Based on our findings, we see utility for an intraoperative or immediate postoperative radiograph following uncomplicated, primary RSA, especially when done as a salvage procedure for indications such as proximal humerus nonunion. However, there is low utility for obtaining an immediate postoperative radiograph in the PACU when indications include osteoarthritis or rotator cuff tear arthropathy.
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- 2021
49. Logical attestation: an authorization architecture for trustworthy computing.
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Emin Gün Sirer, Willem de Bruijn, Patrick Reynolds, Alan Shieh, Kevin Walsh, Dan Williams 0001, and Fred B. Schneider
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- 2011
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50. On the discovery of the main belt source of the enstatite chondrites
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Chrysa Avdellidou, Marco Delbo, Alessandro Morbidelli, Kevin Walsh, Edhah Munaibari, Jules Bourdelle de Micas, Maxime Devogele, Sonia Fornasier, Matthieu Gounelle, and Gerard van Belle
- Abstract
Introduction: Linking a meteorite type to a specific parent asteroid allows us to gain insight into the composition of the latter as well as the time, and indirectly the heliocentric distance of its formation. Up to now there have been established solid links between the HEDs and the inner main belt asteroid family of (4) Vesta [1] as well as between the ordinary chondrites and asteroids belonging to the so-called spectroscopic S-complex [2]. Here we report on our search for the enstatite chondrites parent body. We base our analysis on two facts: that (i) inner main belt asteroid collisional families are the most favoured to deliver meteorites to Earth, and (ii) enstatite chondrites (divided in EH and EL groups) have reflectance spectra that are within the broad asteroid spectroscopic X-complex [3]. The newly discovered asteroid families of Athor and Zita [4] are the only two families of the inner main belt that belong to the spectroscopic X-complex and thus are promising candidates. Methods and Results: In order to investigate the potential link between the enstatite chondrite meteorites and the aforementioned X-complex asteroid families, we performed near-infrared observations of a statistically significant number of members of Athor and Zita. These were combined with the visible data from the literature and finally each asteroid spectrum was classified using the most common asteroid spectral taxonomy. We showed that the Athor and Zita families are spectroscopically distinct from each other and homogenous among their respective members. Moreover, both families have distinct geometric albedo values, with Athor family being brighter. Focusing on the Athor family, we performed curve matching and absolute reflectance comparison with all the available laboratory meteorite spectra in NASA Reflectance Experiment Laboratory and Planetary Spectrophotometer Facility databases. We will report on our matching and provide a number of further evidence that inner main belt families could indeed deliver enstatite chondrites to Earth. Acknowledgments: We acknowledge support from the ANR ORIGINS (ANR-18-CE31-13-0014). CA was supported by the project “Investissements d’Avenir” UCA-JEDI (ANR-15-IDEX-01) and the European Space Agency, AM acknowledges support from the ERC advanced grant HolyEarth N. 101019380. KJW acknowledges support from the Project ESPRESSO, a NASA SSERVI program at SwRI. This work is based on data provided by the Minor Planet Physical Properties Catalogue (MP3C, mp3c.oca.eu) of the Observatoire de la Côte d'Azur. This research utilises spectra acquired at the NASA RELAB facility at Brown University and at Planetary Spectrophotometer Facility (PSF) at University of Winnipeg.References: [1] Russell C.T. et al. 2012, Science 336, 6082, 684.[2] Reddy V. et al. 2015, Asteroids IV, University of Arizona Press, Tucson, 895, 43-63[3] Vernazza P. et al. 2009. Icarus 202, 2, 477-486.[4] Delbo M. et al. 2019. Astronomy & Astrophysics 624, A69.
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- 2022
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