84 research outputs found
Immersive Visualization in Biomedical Computational Fluid Dynamics and Didactic Teaching and Learning
Virtual reality (VR) can stimulate active learning, critical thinking, decision making and improved performance. It requires a medium to show virtual content, which is called a virtual environment (VE). The MARquette Visualization Lab (MARVL) is an example of a VE. Robust processes and workflows that allow for the creation of content for use within MARVL further increases the userbase for this valuable resource. A workflow was created to display biomedical computational fluid dynamics (CFD) and complementary data in a wide range of VE’s. This allows a researcher to study the simulation in its natural three-dimensional (3D) morphology. In addition, it is an exciting way to extract more information from CFD results by taking advantage of improved depth cues, a larger display canvas, custom interactivity, and an immersive approach that surrounds the researcher. The CFD to VR workflow was designed to be basic enough for a novice user. It is also used as a tool to foster collaboration between engineers and clinicians. The workflow aimed to support results from common CFD software packages and across clinical research areas. ParaView, Blender and Unity were used in the workflow to take standard CFD files and process them for viewing in VR. Designated scripts were written to automate the steps implemented in each software package. The workflow was successfully completed across multiple biomedical vessels, scales and applications including: the aorta with application to congenital cardiovascular disease, the Circle of Willis with respect to cerebral aneurysms, and the airway for surgical treatment planning. The workflow was completed by novice users in approximately an hour. Bringing VR further into didactic teaching within academia allows students to be fully immersed in their respective subject matter, thereby increasing the students’ sense of presence, understanding and enthusiasm. MARVL is a space for collaborative learning that also offers an immersive, virtual experience. A workflow was created to view PowerPoint presentations in 3D using MARVL. A resulting Immersive PowerPoint workflow used PowerPoint, Unity and other open-source software packages to display the PowerPoint presentations in 3D. The Immersive PowerPoint workflow can be completed in under thirty minutes
The remnants of galaxy formation from a panoramic survey of the region around M31
In hierarchical cosmological models, galaxies grow in mass through the
continual accretion of smaller ones. The tidal disruption of these systems is
expected to result in loosely bound stars surrounding the galaxy, at distances
that reach times the radius of the central disk. The number,
luminosity and morphology of the relics of this process provide significant
clues to galaxy formation history, but obtaining a comprehensive survey of
these components is difficult because of their intrinsic faintness and vast
extent. Here we report a panoramic survey of the Andromeda galaxy (M31). We
detect stars and coherent structures that are almost certainly remnants of
dwarf galaxies destroyed by the tidal field of M31. An improved census of their
surviving counterparts implies that three-quarters of M31's satellites brighter
than await discovery. The brightest companion, Triangulum (M33), is
surrounded by a stellar structure that provides persuasive evidence for a
recent encounter with M31. This panorama of galaxy structure directly confirms
the basic tenets of the hierarchical galaxy formation model and reveals the
shared history of M31 and M33 in the unceasing build-up of galaxies.Comment: Published in Nature. Supplementary movie available at
https://www.astrosci.ca/users/alan/PANDAS/Latest%20news%3A%20movie%20of%20orbit.htm
The Maunakea Spectroscopic Explorer Book 2018
(Abridged) This is the Maunakea Spectroscopic Explorer 2018 book. It is
intended as a concise reference guide to all aspects of the scientific and
technical design of MSE, for the international astronomy and engineering
communities, and related agencies. The current version is a status report of
MSE's science goals and their practical implementation, following the System
Conceptual Design Review, held in January 2018. MSE is a planned 10-m class,
wide-field, optical and near-infrared facility, designed to enable
transformative science, while filling a critical missing gap in the emerging
international network of large-scale astronomical facilities. MSE is completely
dedicated to multi-object spectroscopy of samples of between thousands and
millions of astrophysical objects. It will lead the world in this arena, due to
its unique design capabilities: it will boast a large (11.25 m) aperture and
wide (1.52 sq. degree) field of view; it will have the capabilities to observe
at a wide range of spectral resolutions, from R2500 to R40,000, with massive
multiplexing (4332 spectra per exposure, with all spectral resolutions
available at all times), and an on-target observing efficiency of more than
80%. MSE will unveil the composition and dynamics of the faint Universe and is
designed to excel at precision studies of faint astrophysical phenomena. It
will also provide critical follow-up for multi-wavelength imaging surveys, such
as those of the Large Synoptic Survey Telescope, Gaia, Euclid, the Wide Field
Infrared Survey Telescope, the Square Kilometre Array, and the Next Generation
Very Large Array.Comment: 5 chapters, 160 pages, 107 figure
SPLUS J142445.34-254247.1: An R-Process Enhanced, Actinide-Boost, Extremely Metal-Poor star observed with GHOST
We report on the chemo-dynamical analysis of SPLUS J142445.34-254247.1, an
extremely metal-poor halo star enhanced in elements formed by the rapid
neutron-capture process. This star was first selected as a metal-poor candidate
from its narrow-band S-PLUS photometry and followed up spectroscopically in
medium-resolution with Gemini South/GMOS, which confirmed its low-metallicity
status. High-resolution spectroscopy was gathered with GHOST at Gemini South,
allowing for the determination of chemical abundances for 36 elements, from
carbon to thorium. At [Fe/H]=-3.39, SPLUS J1424-2542 is one of the lowest
metallicity stars with measured Th and has the highest logeps(Th/Eu) observed
to date, making it part of the "actinide-boost" category of r-process enhanced
stars. The analysis presented here suggests that the gas cloud from which SPLUS
J1424-2542 was formed must have been enriched by at least two progenitor
populations. The light-element (Z<=30) abundance pattern is consistent with the
yields from a supernova explosion of metal-free stars with 11.3-13.4 Msun, and
the heavy-element (Z>=38) abundance pattern can be reproduced by the yields
from a neutron star merger (1.66Msun and 1.27Msun) event. A kinematical
analysis also reveals that SPLUS J1424-2542 is a low-mass, old halo star with a
likely in-situ origin, not associated with any known early merger events in the
Milky Way.Comment: 26 pages, 11 figures, accepted for publication on Ap
An agenda for ethics and justice in adaptation to climate change
As experts predict that at least some irreversible climate change will occur with potentially disastrous effects on the lives and well-being of vulnerable communities around the world, it is paramount to ensure that these communities are resilient and have adaptive capacity to withstand the consequences. Adaptation and resilience planning present several ethical issues that need to be resolved if we are to achieve successful adaptation and resilience to climate change, taking into consideration vulnerabilities and inequalities in terms of power, income, gender, age, sexuality, race, culture, religion, and spatiality. Sustainable adaptation and resilience planning that addresses these ethical issues requires interdisciplinary dialogues between the natural sciences, social sciences, and philosophy, in order to integrate empirical insights on socioeconomic inequality and climate vulnerability with ethical analysis of the underlying causes and consequences of injustice in adaptation and resilience. In this paper, we set out an interdisciplinary research agenda for the inclusion of ethics and justice theories in adaptation and resilience planning, particularly into the Sixth Assessment Report of the International Panel on Climate Change (IPCC AR6). We present six core discussions that we believe should be an integral part of these interdisciplinary dialogues on adaptation and resilience as part of IPCC AR6, especially Chapters 2 (“Terrestial and freshwater ecosystems and their services”), 6 (“Cities, settlements and key infrastructure”), 7 (“Health, wellbeing and the changing structure of communities”), 8 (“Poverty, livelihoods and sustainable development”), 16 “Key risks across sectors and regions”), 17 (“Decision-making options for managing risk”), and 18 (“Climate resilient development pathways”).: (i) Where does ‘justice’ feature in resilience and adaptation planning and what does it require in that regard?; (ii) How can it be ensured that adaptation and resilience strategies protect and take into consideration and represent the interest of the most vulnerable women and men, and communities?; (iii) How can different forms of knowledge be integrated within adaptation and resilience planning?; (iv) What trade-offs need to be made when focusing on resilience and adaptation and how can they be resolved?; (v) What roles and responsibilities do different actors have to build resilience and achieve adaptation?; (vi) Finally, what does the focus on ethics imply for the practice of adaptation and resilience planning
Elective surgery cancellations due to the COVID-19 pandemic: global predictive modelling to inform surgical recovery plans.
BACKGROUND: The COVID-19 pandemic has disrupted routine hospital services globally. This study estimated the total number of adult elective operations that would be cancelled worldwide during the 12 weeks of peak disruption due to COVID-19. METHODS: A global expert response study was conducted to elicit projections for the proportion of elective surgery that would be cancelled or postponed during the 12 weeks of peak disruption. A Bayesian β-regression model was used to estimate 12-week cancellation rates for 190 countries. Elective surgical case-mix data, stratified by specialty and indication (surgery for cancer versus benign disease), were determined. This case mix was applied to country-level surgical volumes. The 12-week cancellation rates were then applied to these figures to calculate the total number of cancelled operations. RESULTS: The best estimate was that 28 404 603 operations would be cancelled or postponed during the peak 12 weeks of disruption due to COVID-19 (2 367 050 operations per week). Most would be operations for benign disease (90·2 per cent, 25 638 922 of 28 404 603). The overall 12-week cancellation rate would be 72·3 per cent. Globally, 81·7 per cent of operations for benign conditions (25 638 922 of 31 378 062), 37·7 per cent of cancer operations (2 324 070 of 6 162 311) and 25·4 per cent of elective caesarean sections (441 611 of 1 735 483) would be cancelled or postponed. If countries increased their normal surgical volume by 20 per cent after the pandemic, it would take a median of 45 weeks to clear the backlog of operations resulting from COVID-19 disruption. CONCLUSION: A very large number of operations will be cancelled or postponed owing to disruption caused by COVID-19. Governments should mitigate against this major burden on patients by developing recovery plans and implementing strategies to restore surgical activity safely
Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study
Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery
Peer reviewe
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
- …