9,166 results on '"Nixon, P"'
Search Results
152. KRAS allelic imbalance drives tumour initiation yet suppresses metastasis in colorectal cancer in vivo
- Author
-
Najumudeen, Arafath K., Fey, Sigrid K., Millett, Laura M., Ford, Catriona A., Gilroy, Kathryn, Gunduz, Nuray, Ridgway, Rachel A., Anderson, Eve, Strathdee, Douglas, Clark, William, Nixon, Colin, Morton, Jennifer P., Campbell, Andrew D., and Sansom, Owen J.
- Published
- 2024
- Full Text
- View/download PDF
153. Ribosomal profiling of human endogenous retroviruses in healthy tissues
- Author
-
Dopkins, Nicholas, Singh, Bhavya, Michael, Stephanie, Zhang, Panpan, Marston, Jez L., Fei, Tongyi, Singh, Manvendra, Feschotte, Cedric, Collins, Nicholas, Bendall, Matthew L., and Nixon, Douglas F.
- Published
- 2024
- Full Text
- View/download PDF
154. Navigating the complexity of a collaborative, system-wide public health programme: learning from a longitudinal qualitative evaluation of the ActEarly City Collaboratory
- Author
-
Nixon, Laura, Sheard, Laura, Sheringham, Jessica, Creaser, Amy, Iqbal, Halima, Gansallo, Patience, Mansukoski, Liina, Bryant, Maria, and Lockyer, Bridget
- Published
- 2024
- Full Text
- View/download PDF
155. “Something’s got to give”: A Qualitative Exploration of Policies and Practices by Child Welfare Services in Cases of Children Exposed to Intimate Partner Violence in Ontario, Canada
- Author
-
O’Connor, Carolyn, Alaggia, Ramona, and Nixon, Kendra L.
- Published
- 2024
- Full Text
- View/download PDF
156. Assessment of corrosion resistance and reliability of Cu/diamond composite materials in aquatic environment
- Author
-
Poulose, Nixon and Selvakumar, P.
- Published
- 2024
- Full Text
- View/download PDF
157. Poorly differentiated thyroid carcinomas: conceptual controversy and clinical impact
- Author
-
Coca-Pelaz, Andrés, Rodrigo, Juan P., Agaimy, Abbas, Williams, Michelle D., Saba, Nabil F., Nuyts, Sandra, Randolph, Gregory W., López, Fernando, Vander Poorten, Vincent, Kowalski, Luiz P., Civantos, Francisco J., Zafereo, Mark E., Mäkitie, Antti A., Cohen, Oded, Nixon, Iain J., Rinaldo, Alessandra, and Ferlito, Alfio
- Published
- 2024
- Full Text
- View/download PDF
158. GaitASMS: gait recognition by adaptive structured spatial representation and multi-scale temporal aggregation
- Author
-
Sun, Yan, Long, Hu, Feng, Xueling, and Nixon, Mark
- Published
- 2024
- Full Text
- View/download PDF
159. Force-controlled release of small molecules with a rotaxane actuator
- Author
-
Chen, Lei, Nixon, Robert, and De Bo, Guillaume
- Published
- 2024
- Full Text
- View/download PDF
160. Enhancing wear resistance, hardness, and thermal conductivity of copper diamond composites through optimization strategies
- Author
-
Poulose, Nixon and Selvakumar, P.
- Published
- 2024
- Full Text
- View/download PDF
161. 15-Year Analysis of Surgical Approaches and Outcomes for Coarctation in 132 Neonates and Infants
- Author
-
Stukov, Yuriy, Jacobs, Jeffrey P., Sharaf, Omar M., Peek, Giles J., Pitkin, Andrew D., Cruz Beltrán, Susana C., Lopez-Colon, Dalia, Nixon, Connie S., and Bleiweis, Mark S.
- Published
- 2024
- Full Text
- View/download PDF
162. The practice of Daylight Saving Time in Canada: Its suitability with respect to sleep and circadian rhythms
- Author
-
De Koninck, Joseph, Nixon, Ashley, and Godbout, Roger
- Published
- 2024
- Full Text
- View/download PDF
163. Mapping of Family Reported Outcome Measure (FROM-16) scores to EQ-5D: algorithm to calculate utility values
- Author
-
Shah, R., Salek, M. S., Finlay, A. Y., Kay, R., Nixon, S. J., Otwombe, K., Ali, F. M., and Ingram, J. R.
- Published
- 2024
- Full Text
- View/download PDF
164. Effects of the Digital Intervention StudentPOWR on the Subjective Wellbeing of Students Studying from Home: a Randomized Wait-List Control Trial
- Author
-
Nixon, Louise, Slattery, Brian, Cassese, Alberto, and ten Hoor, Gill
- Published
- 2024
- Full Text
- View/download PDF
165. Medical students’ perspectives on and understanding of anesthesiology: a Canadian cross-sectional survey
- Author
-
Nixon, Michael, Brundage, Monica, Cordovani, Ligia, Carr, Adrienne, Ewusie, Joycelyne, and Cordovani, Daniel
- Published
- 2024
- Full Text
- View/download PDF
166. Room-Scale CO2 Injections in a Physical Reservoir Model with Faults
- Author
-
Fernø, M. A., Haugen, M., Eikehaug, K., Folkvord, O., Benali, B., Both, J. W, Storvik, E., Nixon, C. W., Gawthrope, R. L., and Nordbotten, J. M.
- Published
- 2024
- Full Text
- View/download PDF
167. Posterior vitreous detachment and retinal tear – a prospective study of community referrals
- Author
-
Nixon, Thomas R. W., Davie, Rebecca L., and Snead, Martin P.
- Published
- 2024
- Full Text
- View/download PDF
168. Activation of human endogenous retroviruses and its physiological consequences
- Author
-
Dopkins, Nicholas and Nixon, Douglas F.
- Published
- 2024
- Full Text
- View/download PDF
169. IgG4-related disease: an update on pathology and diagnostic criteria with a focus on salivary gland manifestations
- Author
-
Czarnywojtek, Agata, Agaimy, Abbas, Pietrończyk, Krzysztof, Nixon, Iain J., Vander Poorten, Vincent, Mäkitie, Antti A., Zafereo, Mark, Florek, Ewa, Sawicka-Gutaj, Nadia, Ruchała, Marek, and Ferlito, Alfio
- Published
- 2024
- Full Text
- View/download PDF
170. Identifiability of Points and Rigidity of Hypergraphs under Algebraic Constraints
- Author
-
Cruickshank, James, Mohammadi, Fatemeh, Nixon, Anthony, and Tanigawa, Shin-ichi
- Subjects
Mathematics - Metric Geometry ,Computer Science - Computational Geometry ,Mathematics - Combinatorics - Abstract
The identifiability problem arises naturally in a number of contexts in mathematics and computer science. Specific instances include local or global rigidity of graphs and unique completability of partially-filled tensors subject to rank conditions. The identifiability of points on secant varieties has also been a topic of much research in algebraic geometry. It is often formulated as the problem of identifying a set of points satisfying a given set of algebraic relations. A key question then is to prove sufficient conditions for relations to guarantee the identifiability of the points. This paper proposes a new general framework for capturing the identifiability problem when a set of algebraic relations has a combinatorial structure and develops tools to analyse the impact of the underlying combinatorics on the local or global identifiability of points. Our framework is built on the language of graph rigidity, where the measurements are Euclidean distances between two points, but applicable in the generality of hypergraphs with arbitrary algebraic measurements. We establish necessary and sufficient (hyper)graph theoretical conditions for identifiability by exploiting techniques from graph rigidity theory and algebraic geometry of secant varieties. In particular our work analyses combinatorially the effect of non-generic projections of secant varieties.
- Published
- 2023
171. Optical Polarization Analogs in Inelastic Free Electron Scattering
- Author
-
Bourgeois, Marc R., Nixon, Austin G., Chalifour, Matthieu, and Masiello, David J.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Advances in the ability to manipulate free electron phase profiles within the electron microscope have spurred development of quantum-mechanical descriptions of electron energy loss (EEL) processes involving transitions between phase-shaped transverse states. Here, we elucidate an underlying connection between two ostensibly distinct optical polarization analogs identified in EEL experiments as manifestations of the same conserved scattering flux. Our work introduces a procedure for probing general tensorial target characteristics including global mode symmetries and local polarization.
- Published
- 2023
- Full Text
- View/download PDF
172. Real-Time Scheduling for 802.1Qbv Time-Sensitive Networking (TSN): A Systematic Review and Experimental Study
- Author
-
Xue, Chuanyu, Zhang, Tianyu, Zhou, Yuanbin, Nixon, Mark, Loveless, Andrew, and Han, Song
- Subjects
Computer Science - Networking and Internet Architecture ,Computer Science - Distributed, Parallel, and Cluster Computing - Abstract
Time-Sensitive Networking (TSN) has been recognized as one of the key enabling technologies for Industry 4.0 and has been deployed in many mission- and safety-critical applications e.g., automotive and aerospace systems. Given the stringent real-time requirements of these applications, the Time-Aware Shaper (TAS) draws special attention among TSN's many traffic shapers due to its ability to achieve deterministic timing guarantees. Many scheduling methods for TAS shapers have been recently developed that claim to improve system schedulability. However, these scheduling methods have yet to be thoroughly evaluated, especially through experimental comparisons, to provide a systematical understanding of their performance using different evaluation metrics in diverse application scenarios. In this paper, we fill this gap by presenting a systematic review and experimental study on existing TAS-based scheduling methods for TSN. We first categorize the system models employed in these works along with the specific problems they aim to solve, and outline the fundamental considerations in the designs of TAS-based scheduling methods. We then perform an extensive evaluation on 17 representative solutions using both high-fidelity simulations and a real-life TSN testbed, and compare their performance under both synthetic scenarios and real-life industrial use cases. Through these experimental studies, we identify the limitations of individual scheduling methods and highlight several important findings. We expect this work will provide foundational knowledge and performance benchmarks needed for future studies on real-time TSN scheduling., Comment: 21 pages, 6 authors, RTAS24 tech report
- Published
- 2023
- Full Text
- View/download PDF
173. Spitzer IRS Observations of Titan as a Precursor to JWST MIRI Observations
- Author
-
Coy, Brandon Park, Nixon, Conor A., Rowe-Gurney, Naomi, Achterberg, Richard, Lombardo, Nicholas A., Fletcher, Leigh N., and Irwin, Patrick
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
In this work we present, for the first time, infrared spectra of Titan from the Spitzer Space Telescope ($2004-2009$). The data are from both the short wavelength-low resolution (SL, $5.13-14.29\mathrm{\mu m}, R\sim60-127$) and short wavelength-high resolution channels (SH, $9.89 - 19.51\mathrm{\mu m}, R\sim600$) showing the emissions of CH$_{4}$, C$_{2}$H$_{2}$, C$_{2}$H$_{4}$, C$_{2}$H$_{6}$, C$_{3}$H$_{4}$, C$_{3}$H$_{6}$, C$_{3}$H$_{8}$, C$_{4}$H$_{2}$, HCN, HC$_{3}$N, and CO$_{2}$. We compare the results obtained for Titan from Spitzer to those of the Cassini Composite Infrared Spectrometer (CIRS) for the same time period, focusing on the $16.35-19.35\mathrm{\mu m}$ wavelength range observed by the SH channel but impacted by higher noise levels in CIRS observations. We use the SH data to provide estimated haze extinction cross-sections for the $16.67-17.54\mathrm{\mu m}$ range that are missing in previous studies. We conclude by identifying spectral features in the $16.35-19.35\mathrm{\mu m}$ wavelength range, including two prominent emission features at 16.39 and $17.35\mathrm{\mu m}$, that could be analyzed further through upcoming James Webb Space Telescope Cycle 1 observations with the Mid-Infrared Instrument ($5.0-28.3\mathrm{\mu m}, R\sim1500-3500$). We also highlight gaps in current spectroscopic knowledge of molecular bands, including candidate trace species such as C$_{60}$ and detected trace species such as C$_{3}$H$_{6}$, that could be addressed by theoretical and laboratory study., Comment: Accepted to Planetary Science Journal April 28, 2023
- Published
- 2023
- Full Text
- View/download PDF
174. A reflective, metal-rich atmosphere for GJ 1214b from its JWST phase curve
- Author
-
Kempton, Eliza M. -R., Zhang, Michael, Bean, Jacob L., Steinrueck, Maria E., Piette, Anjali A. A., Parmentier, Vivien, Malsky, Isaac, Roman, Michael T., Rauscher, Emily, Gao, Peter, Bell, Taylor J., Xue, Qiao, Taylor, Jake, Savel, Arjun B., Arnold, Kenneth E., Nixon, Matthew C., Stevenson, Kevin B., Mansfield, Megan, Kendrew, Sarah, Zieba, Sebastian, Ducrot, Elsa, Dyrek, Achrène, Lagage, Pierre-Olivier, Stassun, Keivan G., Henry, Gregory W., Barman, Travis, Lupu, Roxana, Malik, Matej, Kataria, Tiffany, Ih, Jegug, Fu, Guangwei, Welbanks, Luis, and McGill, Peter
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
There are no planets intermediate in size between Earth and Neptune in our Solar System, yet these objects are found around a substantial fraction of other stars. Population statistics show that close-in planets in this size range bifurcate into two classes based on their radii. It is hypothesized that the group with larger radii (referred to as "sub-Neptunes") is distinguished by having hydrogen-dominated atmospheres that are a few percent of the total mass of the planets. GJ 1214b is an archetype sub-Neptune that has been observed extensively using transmission spectroscopy to test this hypothesis. However, the measured spectra are featureless, and thus inconclusive, due to the presence of high-altitude aerosols in the planet's atmosphere. Here we report a spectroscopic thermal phase curve of GJ 1214b obtained with JWST in the mid-infrared. The dayside and nightside spectra (average brightness temperatures of 553 $\pm$ 9 and 437 $\pm$ 19 K, respectively) each show >3$\sigma$ evidence of absorption features, with H$_2$O as the most likely cause in both. The measured global thermal emission implies that GJ 1214b's Bond albedo is 0.51 $\pm$ 0.06. Comparison between the spectroscopic phase curve data and three-dimensional models of GJ 1214b reveal a planet with a high metallicity atmosphere blanketed by a thick and highly reflective layer of clouds or haze., Comment: Published online in Nature on May 10, 2023
- Published
- 2023
- Full Text
- View/download PDF
175. The Hazy and Metal-Rich Atmosphere of GJ 1214 b Constrained by Near and Mid-Infrared Transmission Spectroscopy
- Author
-
Gao, Peter, Piette, Anjali A. A., Steinrueck, Maria E., Nixon, Matthew C., Zhang, Michael, Kempton, Eliza M. R., Bean, Jacob L., Rauscher, Emily, Parmentier, Vivien, Batalha, Natasha E., Savel, Arjun B., Arnold, Kenneth E., Roman, Michael T., Malsky, Isaac, and Taylor, Jake
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
The near-infrared transmission spectrum of the warm sub-Neptune exoplanet GJ 1214 b has been observed to be flat and featureless, implying a high metallicity atmosphere with abundant aerosols. Recent JWST MIRI LRS observations of a phase curve of GJ 1214 b showed that its transmission spectrum is flat out into the mid-infrared. In this paper, we use the combined near- and mid-infrared transmission spectrum of GJ 1214 b to constrain its atmospheric composition and aerosol properties. We generate a grid of photochemical haze models using an aerosol microphysics code for a number of background atmospheres spanning metallicities from 100 to 1000 $\times$ solar, as well as a steam atmosphere scenario. The flatness of the combined data set largely rules out atmospheric metallicities $\leq$300 $\times$ solar due to their large corresponding molecular feature amplitudes, preferring values $\geq$1000 $\times$ solar and column haze production rates $\geq$10$^{-10}$ g cm$^{-2}$ s$^{-1}$. The steam atmosphere scenario with similarly high haze production rates also exhibit sufficiently small molecular features to be consistent with the transmission spectrum. These compositions imply that atmospheric mean molecular weights $\geq$15 g mol$^{-1}$ are needed to fit the data. Our results suggest that haze production is highly efficient on GJ 1214 b and could involve non-hydrocarbon, non-nitrogen haze precursors. Further characterization of GJ 1214 b's atmosphere would likely require multiple transits and eclipses using JWST across the near and mid-infrared, potentially complemented by groundbased high resolution transmission spectroscopy., Comment: 21 pages, 10 figures, 4 tables. Accepted for publication by ApJ
- Published
- 2023
- Full Text
- View/download PDF
176. Switching via Wave Interaction in Topological Photonic Lattices
- Author
-
Ablowitz, Mark J., Cole, Justin T., and Nixon, S. D.
- Subjects
Physics - Optics ,Nonlinear Sciences - Pattern Formation and Solitons ,78M35, 37N20 - Abstract
A honeycomb Floquet lattice with helically rotating waveguides and an interface separating two counter-propagating subdomains is analyzed. Two topologically protected localized waves propagate unidirectionally along the interface. Switching can occur when these interface modes reach the edge of the lattice and the light splits into waves traveling in two opposite directions. The incoming mode, traveling along the interface, can be routed entirely or partially along either lattice edge with the switching direction based on a suitable mixing of the interface modes.
- Published
- 2023
177. Consistent Point Data Assimilation in Firedrake and Icepack
- Author
-
Nixon-Hill, Reuben W., Shapero, Daniel, Cotter, Colin J., and Ham, David A.
- Subjects
Computer Science - Mathematical Software ,Mathematics - Numerical Analysis - Abstract
When estimating quantities and fields that are difficult to measure directly, such as the fluidity of ice, from point data sources, such as satellite altimetry, it is important to solve a numerical inverse problem that is formulated with Bayesian consistency. Otherwise, the resultant probability density function for the difficult to measure quantity or field will not be appropriately clustered around the truth. In particular, the inverse problem should be formulated by evaluating the numerical solution at the true point locations for direct comparison with the point data source. If the data are first fitted to a gridded or meshed field on the computational grid or mesh, and the inverse problem formulated by comparing the numerical solution to the fitted field, the benefits of additional point data values below the grid density will be lost. We demonstrate, with examples in the fields of groundwater hydrology and glaciology, that a consistent formulation can increase the accuracy of results and aid discourse between modellers and observationalists. To do this, we bring point data into the finite element method ecosystem as discontinuous fields on meshes of disconnected vertices. Point evaluation can then be formulated as a finite element interpolation operation (dual-evaluation). This new abstraction is well-suited to automation, including automatic differentiation. We demonstrate this through implementation in Firedrake, which generates highly optimised code for solving Partial Differential Equations (PDEs) with the finite element method. Our solution integrates with dolfin-adjoint/pyadjoint, allowing PDE-constrained optimisation problems, such as data assimilation, to be solved through forward and adjoint mode automatic differentiation., Comment: This version: Added missing affiliation
- Published
- 2023
178. Orbital stability of two circumbinary planets around misaligned eccentric binaries
- Author
-
Chen, Cheng, Lubow, Stephen H., Martin, Rebecca G., and Nixon, C. J.
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
With $n$-body simulations we investigate the stability of tilted circumbinary planetary systems consisting of two nonzero mass planets. The planets are initially in circular orbits that are coplanar to each other, as would be expected if they form in a flat but tilted circumbinary gas disc and decouple from the disc within a time difference that is much less than the disc nodal precession period. We constrain the parameters of stable multiple planet circumbinary systems. Both planet-planet and planet-binary interactions can cause complex planet tilt oscillations which can destabilise the orbits of one or both planets. The system is considerably more unstable than the effects of these individual interactions would suggest, due to the interplay between these two interactions. The stability of the system is sensitive to the binary eccentricity, the orbital tilt and the semi-major axes of the two circumbinary planets. With an inner planet semi-major axis of $5\,a_{\rm b}$, where $a_{\rm b}$ is semi-major axis of the binary, the system is generally stable if the outer planet is located at $\gtrsim 8\,a_{\rm b}$, beyond the 2:1 mean motion resonance with the inner planet. For larger inner planet semi-major axis the system is less stable because the von-Zeipel--Kozai--Lidov mechanism plays a significant role, particularly for low binary-eccentricity cases. For the unstable cases, the most likely outcome is that one planet is ejected and the other remains bound on a highly eccentric orbit. Therefore we suggest that this instability is an efficient mechanism for producing free-floating planets., Comment: 13 pages, 10 figures
- Published
- 2023
- Full Text
- View/download PDF
179. In-Service Mathematics Teachers' Knowledge of Differentiated Instruction
- Author
-
Kyeremeh, Patrick, Adzifome, Nixon Saba, and Amoah, Emmanuel Kojo
- Abstract
This study sought to investigate in-service mathematics teachers' knowledge of differentiated instruction in junior high schools in Tano South Municipality of Ghana. The study adopted an explanatory sequential mixed method design. We employed a sample of 50 JHS mathematics teachers comprising 41 general in-service teachers and 9 special in-service teachers in the quantitative study through a proportionate stratified sampling technique. In the qualitative phase, 6 JHS mathematics teachers comprising 4 general in-service teachers and 2 special in-service teachers were purposively selected and interviewed. In line with the design adopted, the quantitative data obtained through a questionnaire was first collected and analysed. This was followed by the qualitative data obtained through semi-structured interviews. The quantitative data were analysed using both descriptive statistical tools (such as frequency counts, percentages, mean, standard deviation, and average per item rating), and inferential statistical tools (independent samples t-test). Qualitative data used inductive content analysis. Among the findings, we found no statistically significant difference in the knowledge scores on differentiated instruction for general in-service teachers and special in-service teachers (t = -0.80, df = 48, p > 0.05). We, therefore, recommend teacher education institutions review their mathematics curriculum to reflect the use of differentiated instructional approaches among mathematics teachers.
- Published
- 2022
180. DYNamic Assessment of Multi‐Organ level dysfunction in patients recovering from COVID‐19: DYNAMO COVID‐19
- Author
-
Ayushman Gupta, Rosemary Nicholas, Jordan J. McGing, Aline V. Nixon, Joanne E. Mallinson, Tricia M. McKeever, Christopher R. Bradley, Mathew Piasecki, Eleanor F. Cox, James Bonnington, Janet M. Lord, Christopher E. Brightling, Rachael A. Evans, Ian P. Hall, Susan T. Francis, Paul L. Greenhaff, and Charlotte E. Bolton
- Subjects
COVID‐19 ,pathophysiology ,post‐acute COVID‐19 syndrome ,recovery ,Physiology ,QP1-981 - Abstract
Abstract We evaluated the impacts of COVID‐19 on multi‐organ and metabolic function in patients following severe hospitalised infection compared to controls. Patients (n = 21) without previous diabetes, cardiovascular or cerebrovascular disease were recruited 5–7 months post‐discharge alongside controls (n = 10) with similar age, sex and body mass. Perceived fatigue was estimated (Fatigue Severity Scale) and the following were conducted: oral glucose tolerance (OGTT) alongside whole‐body fuel oxidation, validated magnetic resonance imaging and spectroscopy during resting and supine controlled exercise, dual‐energy X‐ray absorptiometry, short physical performance battery (SPPB), intra‐muscular electromyography, quadriceps strength and fatigability, and daily step‐count. There was a greater insulin response (incremental area under the curve, median (inter‐quartile range)) during the OGTT in patients [18,289 (12,497–27,448) mIU/min/L] versus controls [8655 (7948–11,040) mIU/min/L], P
- Published
- 2024
- Full Text
- View/download PDF
181. The Care Trajectories and Nature of Care Received by Children Aged 5–11 Who Are in Need of Therapeutic Residential Care
- Author
-
Catherine Nixon
- Subjects
residential care ,foster care ,foster care strain ,child and adolescent mental health ,relationship-based practice ,therapeutic practice ,Urban groups. The city. Urban sociology ,HT101-395 - Abstract
A total of 10% of children looked after in residential care in Scotland are aged 5–11. Although there has been a significant amount of information published about the care trajectories of adolescents in residential care, there is limited information about the experiences of younger children. In this paper, we explore the care trajectories and nature of care received by 5–11-year-olds identified as being in need of residential care. Our results show that younger children who enter residential care have significant trauma histories and experience significant levels of emotional and behavioural dysregulation that foster carers find challenging to manage, resulting in recurrent placement breakdowns. Residential care, particularly small-group-sized care that adopts social pedagogical and psychotherapeutic approaches, was considered beneficial for addressing the psychosocial and emotional needs of younger children. Despite these findings, there were concerns about the long-term use of residential care for younger children. Our results highlight that there is a need to improve access to paediatric mental health services for children in family-based placements. There is also a need to invest in better training and support for foster carers looking after children in severe distress. Community-based outreach services and in-home respite services provided by residential care teams are one way this could be achieved. Finally, in order to promote earlier and more timeous use of residential care, there is a need to shift societal views around residential care being a placement of last resort to rather being a place of recovery and healing that should sometimes be used as a placement of first resort.
- Published
- 2024
- Full Text
- View/download PDF
182. From pre-test and post-test probabilities to medical decision making
- Author
-
Michelle Pistner Nixon, Farhani Momotaz, Claire Smith, Jeffrey S. Smith, Mark Sendak, Christopher Polage, and Justin D. Silverman
- Subjects
Diagnostic uncertainty ,Bayesian decision theory ,Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Abstract Background A central goal of modern evidence-based medicine is the development of simple and easy to use tools that help clinicians integrate quantitative information into medical decision-making. The Bayesian Pre-test/Post-test Probability (BPP) framework is arguably the most well known of such tools and provides a formal approach to quantify diagnostic uncertainty given the result of a medical test or the presence of a clinical sign. Yet, clinical decision-making goes beyond quantifying diagnostic uncertainty and requires that that uncertainty be balanced against the various costs and benefits associated with each possible decision. Despite increasing attention in recent years, simple and flexible approaches to quantitative clinical decision-making have remained elusive. Methods We extend the BPP framework using concepts of Bayesian Decision Theory. By integrating cost, we can expand the BPP framework to allow for clinical decision-making. Results We develop a simple quantitative framework for binary clinical decisions (e.g., action/inaction, treat/no-treat, test/no-test). Let p be the pre-test or post-test probability that a patient has disease. We show that $$r^{*}=(1-p)/p$$ r ∗ = ( 1 - p ) / p represents a critical value called a decision boundary. In terms of the relative cost of under- to over-acting, $$r^{*}$$ r ∗ represents the critical value at which action and inaction are equally optimal. We demonstrate how this decision boundary can be used at the bedside through case studies and as a research tool through a reanalysis of a recent study which found widespread misestimation of pre-test and post-test probabilities among clinicians. Conclusions Our approach is so simple that it should be thought of as a core, yet previously overlooked, part of the BPP framework. Unlike prior approaches to quantitative clinical decision-making, our approach requires little more than a hand-held calculator, is applicable in almost any setting where the BPP framework can be used, and excels in situations where the costs and benefits associated with a particular decision are patient-specific and difficult to quantify.
- Published
- 2024
- Full Text
- View/download PDF
183. Addressing the Rising Trend in Early-Age-Onset Cancers in Canada
- Author
-
Petra Wildgoose, Filomena Servidio-Italiano, Michael J. Raphael, Monika Slovinec D’Angelo, Cassandra Macaulay, Shaqil Kassam, Nancy Nixon, José Perea, Sarah Hamilton, Ravi Ramjeesingh, Sharlene Gill, Aaron Pollett, Shuji Ogino, Tomotaka Ugai, and Abha Gupta
- Subjects
early age onset cancer ,EAOC ,EAOCRC ,young onset cancer ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
A multi-disciplinary symposium on early-age onset cancer (EAOC) was held in October 2023 to explore challenges experienced by this rapidly growing population. A major outcome of the symposium was recognition of the remarkable similarities of EAOC patients’ journeys across cancer sites. Prevention and early detection of cancer are hindered by a lack of awareness among patients and family doctors that cancer can and does occur in younger persons. Distinct characteristics of the disease—such as a later stage at diagnosis and more aggressive tumor biology—require more potent treatments, which result in profound physical and psychosocial consequences that are unique to this age group. EAOC patient empowerment emerged as another key theme of the symposium. The development of a greater number of specialized clinics was called for, and patient support groups were recognized for the vital role they play in empowering patients and their families. Leading-edge medical advancements hold tremendous hope across the spectrum of EAOC care. New technologies based on genomic profiling, immunotherapy and microbiome alteration contribute to the development of highly effective, personalized approaches to treatment. All symposium participants expressed their commitment to speak with one resounding voice to advocate for equitable access to leading care practices for EAOC patients; thus, a fourth symposium is planned for November 2024.
- Published
- 2024
- Full Text
- View/download PDF
184. A new leaf essential oil from the Andean species Gynoxys szyszylowiczii Hieron. of southern Ecuador: chemical and enantioselective analyses
- Author
-
Yessenia E. Maldonado, Omar Malagón, Nixon Cumbicus, and Gianluca Gilardoni
- Subjects
Medicine ,Science - Abstract
Abstract The essential oil obtained from the dry leaves of Gynoxys szyszylowiczii Hieron. was described in this study for the first time. The chemical analysis, conducted on two stationary phases of different polarity, permitted to identify sixty-four compounds, that were quantified with at least one column. The main components, on a non-polar and polar stationary phase respectively, were germacrene D (21.6–19.2%), α-pinene (4.4–4.9%), n-tricosane (4.3% on both columns), (E)-β-caryophyllene (3.3–4.3%), 1-docosene (3.2–2.8%), α-cadinol (2.8–3.1%), and cis-β-guaiene (2.6–3.0%). This investigation was complemented by the enantioselective analysis of some major chiral compounds, carried out on two chiral selectors based on β-cyclodextrines. As a result, (S)-( +)-α-phellandrene, (S)-( +)-β-phellandrene, and (1S,2R,6R,7R,8R)-( +)-α-copaene appeared enantiomerically pure, whereas α-pinene, β-pinene, terpinen-4-ol, and germacrene D were detected as scalemic mixtures. Finally, linalool was practically racemic. The distillation yield, analytically calculated by weight of dry plant material, was 0.03%.
- Published
- 2024
- Full Text
- View/download PDF
185. A retrospective cross-sectional study of risk factors for communicable disease diagnoses among refugees in mainland Greek camps, 2016–2017
- Author
-
Sarah Elizabeth Scales, Jee Won Park, Rebecca Nixon, Debarati Guha-Sapir, and Jennifer A. Horney
- Subjects
Refugee health ,Complex emergencies ,Communicable disease ,Medicine ,Science - Abstract
Abstract Communicable disease risk is high in refugee camps and reception centers. To better understand the risks for communicable disease diagnoses among refugees and asylum seekers, this study assesses individual- and camp-level risk factors among individuals utilizing Médecins du Monde clinics in four large refugee camps—Elliniko, Malakasa, Koutsochero, and Raidestos—on mainland Greece between July 2016 and May 2017. Descriptive statistics are reported for the demographic characteristics of the study population and for communicable disease burdens within the four camps—Elliniko, Malakasa, Raidestos, and Koutsochero. A hierarchical generalized linear model was used to assess risk factors for communicable disease diagnoses while accounting for individual-level clustering. This study shows marginal patterns in risk factors for communicable disease. Males had marginally higher risk of communicable disease diagnosis than females (OR = 1.12; 95% CI 0.97—1.29), and increased age was more protective against communicable disease for females (OR = 0.957; 95% CI 0.953—0.961) than for males (OR = 0.963; 95% CI 0.959—0.967). Communicable disease risk was significantly different between camps, with Elliniko (OR = 1.58; 95% CI 1.40–1.79) and Malakasa (OR = 1.43; 95% CI 1.25–1.63) having higher odds of communicable disease than Raidestos. The demographic and epidemiologic profiles of displaced populations differ across settings, and epidemiologic baselines for displaced populations are fundamental to evidence-informed provision of humanitarian aid. Further, while influences and risks for negative health outcomes in complex emergencies are broadly, the causal mechanisms that underpin these relationships are not as well understood. Both practitioners and researchers should engage with further research to elucidate the mechanisms through which these risks operate among displaced populations, including multilevel analyses.
- Published
- 2024
- Full Text
- View/download PDF
186. Cassini spacecraft reveals global energy imbalance of Saturn
- Author
-
Xinyue Wang, Liming Li, Xun Jiang, Patrick M. Fry, Robert A. West, Conor A. Nixon, Larry Guan, Thishan D. Karandana G, Ronald Albright, Joshua E. Colwell, Tristan Guillot, Mark D. Hofstadter, Matthew E. Kenyon, Anthony Mallama, Santiago Perez-Hoyos, Agustin Sanchez-Lavega, Amy A. Simon, Daniel Wenkert, and Xi Zhang
- Subjects
Science - Abstract
Abstract The global energy budget is pivotal to understanding planetary evolution and climate behaviors. Assessing the energy budget of giant planets, particularly those with large seasonal cycles, however, remains a challenge without long-term observations. Evolution models of Saturn cannot explain its estimated Bond albedo and internal heat flux, mainly because previous estimates were based on limited observations. Here, we analyze the long-term observations recorded by the Cassini spacecraft and find notably higher Bond albedo (0.41 ± 0.02) and internal heat flux (2.84 ± 0.20 Wm−2) values than previous estimates. Furthermore, Saturn’s global energy budget is not in a steady state and exhibits significant dynamical imbalances. The global radiant energy deficit at the top of the atmosphere, indicative of the planetary cooling of Saturn, reveals remarkable seasonal fluctuations with a magnitude of 16.0 ± 4.2%. Further analysis of the energy budget of the upper atmosphere including the internal heat suggests seasonal energy imbalances at both global and hemispheric scales, contributing to the development of giant convective storms on Saturn. Similar seasonal variabilities of planetary cooling and energy imbalance exist in other giant planets within and beyond the Solar System, a prospect currently overlooked in existing evolutional and atmospheric models.
- Published
- 2024
- Full Text
- View/download PDF
187. Chemical and Enantioselective Analyses of an Unprecedented Essential Oil from Ecuadorian Aiouea montana: A Natural Source of S‑Methyl-O-2-phenylethyl Carbonothioate
- Author
-
Yessenia E. Maldonado, Mayra Montalván, Nixon Cumbicus, and Gianluca Gilardoni
- Subjects
Chemistry ,QD1-999 - Published
- 2024
- Full Text
- View/download PDF
188. New Essential Oils from Ecuadorian Gynoxys cuicochensis Cuatrec. and Gynoxys sancti-antonii Cuatrec. Chemical Compositions and Enantioselective Analyses
- Author
-
Yessenia E. Maldonado, Evelin A. Betancourt, Erika S. León, Omar Malagón, Nixon Cumbicus, and Gianluca Gilardoni
- Subjects
Chemistry ,QD1-999 - Published
- 2024
- Full Text
- View/download PDF
189. Partnering with Consumers – Why would I do it? What is it? How do I do it?
- Author
-
Jodie Nixon
- Subjects
Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Published
- 2024
- Full Text
- View/download PDF
190. Responsiveness and minimal important change of the Family Reported Outcome Measure (FROM-16)
- Author
-
R. Shah, A.Y. Finlay, M.S. Salek, H. Allen, S.J. Nixon, M. Nixon, K. Otwombe, F.M. Ali, and J.R. Ingram
- Subjects
Sensitivity to change ,Responsiveness ,Longitudinal validity ,FROM-16 ,Change over time ,MCID ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background The FROM-16 is a generic family quality of life (QoL) instrument that measures the QoL impact of patients’ disease on their family members/partners. The study aimed to assess the responsiveness of FROM-16 to change and determine Minimal Important Change (MIC). Methods Responsiveness and MIC for FROM-16 were assessed prospectively with patients and their family members recruited from outpatient departments of the University Hospital Wales and University Hospital Llandough, Cardiff, United Kingdom. Patients completed the EQ-5D-3L and a global severity question (GSQ) online at baseline and at 3-month follow-up. Family members completed FROM-16 at baseline and a Global Rating of Change (GRC) in addition to FROM-16 at follow-up. Responsiveness was assessed using the distribution-based (effect size-ES, standardized response mean -SRM) and anchor-based (area under the receiver operating characteristics curve ROC-AUC) approaches and by testing hypotheses on expected correlation strength between FROM-16 change score and patient assessment tools (GSQ and EQ-5D). Cohen’s criteria were used for assessing ES. The AUC ≥ 0.7 was considered a good measure of responsiveness. MIC was calculated using anchor-based (ROC analysis and adjusted predictive modelling) and distribution methods based on standard deviation (SD) and standard error of the measurement (SEM). Results Eighty-three patients with 15 different health conditions and their relatives completed baseline and follow-up questionnaires and were included in the responsiveness analysis. The mean FROM-16 change over 3 months = 1.43 (SD = 4.98). The mean patient EQ-5D change over 3 months = −0.059 (SD = 0.14). The responsiveness analysis showed that the FROM-16 was responsive to change (ES = 0.2, SRM = 0.3; p
- Published
- 2024
- Full Text
- View/download PDF
191. Experiences of Hearing Children of Deaf Parents in Ireland
- Author
-
Heffernan, Georgina and Nixon, Elizabeth
- Abstract
Children of Deaf Adults (CODAs) are uniquely positioned at the intersection between Deaf and hearing communities and often act as interpreters for their parents and hearing individuals. Informed by previous research which has highlighted language brokering as a core element of CODAs' experiences, along with the research which identifies the risk for parentification among CODAs, the aim of this study is to explore CODAs' experiences of their roles within deaf-parented households and beyond the household, at the intersection between the Deaf and hearing worlds. Semi-structured interviews were conducted with 12 CODAs (Mean age 36.33 years, Range 22-54 years) in Ireland. Three themes were generated from the analysis of the interviews: "It was really normal", Facing the Stigma associated with Deafness, and Being a Language Broker. The findings suggest that healthcare and education providers need a better understanding of the unique situations faced by CODAs in their roles as mediators between their parents and the hearing community, so that children and Deaf parents can be appropriately supported in their interactions with professionals.
- Published
- 2023
- Full Text
- View/download PDF
192. A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b.
- Author
-
Coulombe, Louis-Philippe, Benneke, Björn, Challener, Ryan, Piette, Anjali, Wiser, Lindsey, Mansfield, Megan, MacDonald, Ryan, Beltz, Hayley, Feinstein, Adina, Radica, Michael, Savel, Arjun, Dos Santos, Leonardo, Bean, Jacob, Parmentier, Vivien, Wong, Ian, Rauscher, Emily, Komacek, Thaddeus, Kempton, Eliza, Tan, Xianyu, Hammond, Mark, Lewis, Neil, Line, Michael, Lee, Elspeth, Shivkumar, Hinna, Crossfield, Ian, Nixon, Matthew, Rackham, Benjamin, Wakeford, Hannah, Welbanks, Luis, Zhang, Xi, Batalha, Natalie, Berta-Thompson, Zachory, Changeat, Quentin, Désert, Jean-Michel, Espinoza, Néstor, Goyal, Jayesh, Harrington, Joseph, Knutson, Heather, Kreidberg, Laura, López-Morales, Mercedes, Shporer, Avi, Sing, David, Stevenson, Kevin, Aggarwal, Keshav, Ahrer, Eva-Maria, Alam, Munazza, Bell, Taylor, Blecic, Jasmina, Caceres, Claudio, Carter, Aarynn, Casewell, Sarah, Crouzet, Nicolas, Cubillos, Patricio, Decin, Leen, Fortney, Jonathan, Gibson, Neale, Heng, Kevin, Henning, Thomas, Iro, Nicolas, Kendrew, Sarah, Lagage, Pierre-Olivier, Leconte, Jérémy, Lendl, Monika, Lothringer, Joshua, Mancini, Luigi, Mikal-Evans, Thomas, Molaverdikhani, Karan, Nikolov, Nikolay, Ohno, Kazumasa, Palle, Enric, Piaulet, Caroline, Redfield, Seth, Roy, Pierre-Alexis, Tsai, Shang-Min, Venot, Olivia, and Wheatley, Peter
- Abstract
Close-in giant exoplanets with temperatures greater than 2,000 K (ultra-hot Jupiters) have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble Space Telescope (HST) and Spitzer Space Telescope1-3. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis3-12. Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS13 instrument on the JWST. The data span 0.85 to 2.85 μm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6σ confidence) and evidence for optical opacity, possibly attributable to H-, TiO and VO (combined significance of 3.8σ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy-element abundance (metallicity, [Formula: see text] times solar) and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the substellar point that decreases steeply and symmetrically with longitude towards the terminators.
- Published
- 2023
193. Exploring Cultural Diversity and Collaborative Team Communication through a Dynamical Systems Lens
- Author
-
Samadi, Mohammad Amin, Cavazos, Jacqueline G., Lin, Yiwen, and Nixon, Nia
- Abstract
Collaborative problem solving (CPS) is a 21st-century skill essential for learning gains, workplace success, and tackling increasingly complicated global problems. Group diversity plays a vital role during collaborative activities, especially in a digital space. Although CPS involves dynamic communication behaviors, few studies have considered the impact of cultural diversity on the complex and reoccurring discourse involved in CPS tasks. In this study, we explore team conversations during a CPS task to understand the role of cultural diversity on team communication patterns. First, we characterized team dialogues with an existing CPS framework; then used recurrence quantification analysis (RQA) to quantify group communication and capture recurrent patterns. Finally, we compared the patterns across groups with varying degrees of cultural diversity. Our results suggest that groups with higher levels of cultural diversity, compared to more homogeneous groups, had a higher number of group messages, spent more time in group discussions, and demonstrated greater convergence and complexity in communication patterns. These intricate and complicated communication patterns support the notion that cultural diversity can produce both positive and negative outcomes and may explain the perception of cultural diversity in teams as a "double-edged sword". [For the full proceedings, see ED623995.]
- Published
- 2022
194. Room-scale CO2 injections in a physical reservoir model with faults
- Author
-
Ferno, Martin A., Haugen, Malin, Eikehaug, Kristoffer, Folkvord, Olav, Benali, Benyamine, Both, Jakub W., Storvik, Erlend, Nixon, Casey W., Gawthrope, Robert L., and Nordbotten, Jan Martin
- Subjects
Physics - Geophysics - Abstract
We perform a series of repeated CO2 injections in a room-scale physical model of a faulted geological cross-section. Relevant parameters for subsurface carbon sequestration, including multiphase flows, capillary CO2 trapping, dissolution, and convective mixing, are studied and quantified. As part of a forecasting benchmark study, we address and quantify six predefined metrics for storage capacity and security in typical CO2 storage operations. Using the same geometry, we investigate the degree of reproducibility of five repeated experimental runs. Our analysis focuses on physical variations of the spatial distribution of mobile and dissolved CO2, multiphase flow patterns, development in mass of the aqueous and gaseous phases, gravitational fingers, and leakage dynamics. We observe very good reproducibility in homogenous regions with up to 97 % overlap between repeated runs, and that fault-related heterogeneity tends to decrease reproducibility. Notably, we observe an oscillating anticline CO2 leakage behavior from an open anticline with a spill point in the immediate footwall of a normal fault, and discuss the underlying causes for the observed phenomenon within the constraints of the studied system., Comment: Supplementary materials included
- Published
- 2023
195. Tidal capture of stars by supermassive black holes: implications for periodic nuclear transients and quasi-periodic eruptions
- Author
-
Cufari, M., Nixon, C. J., and Coughlin, Eric R.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies - Abstract
Stars that plunge into the center of a galaxy are tidally perturbed by a supermassive black hole (SMBH), with closer encounters resulting in larger perturbations. Exciting these tides comes at the expense of the star's orbital energy, which leads to the naive conclusion that a smaller pericenter (i.e., a closer encounter between the star and SMBH) always yields a more tightly bound star to the SMBH. However, once the pericenter distance is small enough that the star is partially disrupted, morphological asymmetries in the mass lost by the star can yield an \emph{increase} in the orbital energy of the surviving core, resulting in its ejection -- not capture -- by the SMBH. Using smoothed-particle hydrodynamics simulations, we show that the combination of these two effects -- tidal excitation and asymmetric mass loss -- result in a maximum amount of energy lost through tides of $\sim 2.5\%$ of the binding energy of the star, which is significantly smaller than the theoretical maximum of the total stellar binding energy. This result implies that stars that are repeatedly partially disrupted by SMBHs many ($\gtrsim 10$) times on short-period orbits ($\lesssim$ few years), as has been invoked to explain the periodic nuclear transient ASASSN-14ko and quasi-periodic eruptions, must be bound to the SMBH through a mechanism other than tidal capture, such as a dynamical exchange (i.e., Hills capture)., Comment: 4 pages, 2 figures, Accepted for publication in MNRAS
- Published
- 2023
- Full Text
- View/download PDF
196. Experiences of Midwestern obstetric clinicians during the Coronavirus disease 2019 pandemicAJOG Global Reports at a Glance
- Author
-
Drishti D. Sinha, MD, MPHS, Megan Foeller, MD, Abigail S. Bell, BA, Anthony J. Nixon, Jr., MPH, Darrell Hudson, PhD, MPH, Aimee S. James, PhD, MPH, Amy R. Scheffer, Ana A. Baumann, PhD, Emily Diveley, RN, Ebony B. Carter, MD, MPH, Nandini Raghuraman, MD, MSCI, Indira U. Mysorekar, PhD, and Jeannie C. Kelly, MD, MS
- Subjects
challenges ,COVID-19 vaccination ,facilitators ,health equity ,misinformation ,mistrust ,Gynecology and obstetrics ,RG1-991 - Abstract
Background: The Coronavirus disease 2019 (COVID-19) pandemic led to healthcare system changes aimed at minimizing disease transmission that impacted experiences with obstetric healthcare. Objective: To explore experiences of clinicians providing obstetric care during the COVID-19 pandemic. Study Design: Qualitative, in-depth, semi-structured interviews were conducted with five nurse practitioners and 16 obstetrical physicians providing a mix of outpatient and inpatient obstetric care during the COVID-19 pandemic in a mid-sized, Midwestern city in the United States. Interviews elucidated challenges and facilitators of obstetric care provision and vaccination of pregnant patients against COVID-19 during the pandemic. Transcripts were coded inductively then deductively using the Health Equity Implementation Framework (HEIF), which integrates a disparities framework and implementation framework to highlight multilevel factors that influence obstetric care. Thematic analysis was conducted, and thematic saturation was reached. Results: We interviewed 21 clinicians. Clinicians recounted personal challenges such as social isolation and burnout that could be countered by social support. Challenges within the clinical encounter included implementation of infection mitigation efforts, vaccine counseling, and limitations of telehealth. However, when successfully implemented, telehealth facilitated care and circumvented barriers. Clinicians cited challenges at the healthcare system level such as rapidly evolving knowledge and recommendations, restrictive visitor policies, personnel shortage, and inadequate institutional resources to support pandemic-related stressors. However, interdisciplinary care and guidelines available for clinicians facilitated care. Clinicians reported that challenges at the societal level included financial strain, lack of childcare, medical mistrust, politicization of medicine, misinformation, and racism. Societal-level facilitators included insurance access, community outreach, positive policy changes, and fostering trust in medicine. Conclusion: The pandemic produced unique stressors and exacerbated existing challenges for clinicians providing obstetric care. Applying the HEIF to the findings emphasizes the influence of societal factors on all other levels. Identified facilitators can inform interventions to address stressors in obstetric care that have resulted from the changed sociopolitical landscape of the pandemic.
- Published
- 2024
- Full Text
- View/download PDF
197. Superconductivity in mercurides of strontium
- Author
-
Rachel Nixon, Yurii Prots, Mitja Krnel, Nazar Zaremba, Orest Pavlosiuk, Marcus Schmidt, Lev Akselrud, Yuri Grin, and Eteri Svanidze
- Subjects
amalgams ,mercurides ,superconductivity ,mercury ,strontium ,phase diagram ,Technology - Abstract
A large variety of chemical and physical properties are exhibited by mercurides and amalgams. In this work, we have successfully examined seven strontium mercurides: SrHg11, SrHg8, Sr10Hg55, SrHg2, SrHg, Sr3Hg2, and Sr3Hg. The interest in the mercury-rich region is motivated by the large number of mercury-based superconductors that have high mercury content. At the same time, the preparation on the mercury-rich side of the binary phase diagram is experimentally non-trivial, due to the high vapor pressure of mercury and extreme air-sensitivity of mercury-rich compounds. By employing a set of specialized techniques, we were able to discover superconductivity in three mercury-strontium compounds – SrHg11 (Tc=3.2±0.3 K, Hc2=0.18±0.05 T), SrHg8 (Tc=3.0±0.1 K, Hc2=0.35±0.02 T), and Sr10Hg55 (Tc=2.2±0.25 K, Hc2=0.54±0.05 T).
- Published
- 2024
- Full Text
- View/download PDF
198. Influence of Social Deprivation on Patient-Reported Outcomes in Foot and Ankle Patients
- Author
-
Kade Wagers MK, Blessing Ofori-Atta MS, Angela Presson PhD, and Devon Nixon MD
- Subjects
Orthopedic surgery ,RD701-811 - Abstract
Background: The impact of social health on patient-reported outcomes (PROs) is gaining increasing attention within the orthopaedic community. Few studies have explored any relationship between social deprivation levels and PROs in orthopaedic foot and ankle patients. Methods: We retrospectively identified patients who presented to an orthopaedic foot and ankle clinic for new evaluation. Patients completed PROs including PROMIS physical function (PF), PROMIS pain interference (PI), and the Foot and Ankle Ability Measure (FAAM). Social deprivation was measured using the Area Deprivation Index (ADI), a metric that incorporates various domains of poverty, education, housing, and employment. The ADI score quantifies the degree of social deprivation based on the 9-digit home zip code but is not a specific measure to an individual patient. Briefly, a lower ADI indicates less deprivation whereas a higher score denotes greater deprivation. Patient characteristics and outcomes were summarized and stratified by the nationally defined median ADI. Multivariable linear regression models assessed the relationships between PROs and continuous ADI controlling for demographics (age, sex, race/ethnicity, marital status, and employment status). Results: Our cohort consisted of 1565 patients with PRO and appropriate zip code data. Patients in the most-deprived median ADI split had more pain (median PROMIS-PI 62.7 vs 61.2, P = .001) and less function (median PROMIS-PF 37.1 vs 38.6, P = .021) compared with the least-deprived median ADI split. The clinical significance of these findings is unclear, though, given the minimal differences between groups for PROMIS measures. There was no relationship between ADI and FAAM scores. Conclusion: More socially deprived patients presented to the clinic with marginally less function and greater pain. Although statistically significant, the clinical significance of these relationships is unclear and merits further exploration. We plan to continue to study the connection between social deprivation and patient outcomes in specific clinical conditions as well as before/after surgical interventions. Level of Evidence: Level IV, retrospective cases series.
- Published
- 2024
- Full Text
- View/download PDF
199. High-quality lipid suppression and B0 shimming for human brain 1H MRSI
- Author
-
Chathura Kumaragamage, Scott McIntyre, Terence W. Nixon, Henk M. De Feyter, and Robin A. de Graaf
- Subjects
Multicoil ,ECLIPSE ,GABA-MRSI, GOIA ,Human brain ,Lipid suppression ,MRSI ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Magnetic Resonance Spectroscopic Imaging (MRSI) is a powerful technique that can map the metabolic profile in the brain non-invasively. Extracranial lipid contamination and insufficient B0 homogeneity however hampers robustness, and as a result has hindered widespread use of MRSI in clinical and research settings. Over the last six years we have developed highly effective extracranial lipid suppression methods with a second order gradient insert (ECLIPSE) utilizing inner volume selection (IVS) and outer volume suppression (OVS) methods. While ECLIPSE provides > 100-fold in lipid suppression with modest radio frequency (RF) power requirements and immunity to B1+ field variations, axial coverage is reduced for non-elliptical head shapes. In this work we detail the design, construction, and utility of MC-ECLIPSE, a pulsed second order gradient coil with Z2 and X2Y2 fields, combined with a 54-channel multi-coil (MC) array. The MC-ECLIPSE platform allows arbitrary region of interest (ROI) shaped OVS for full-axial slice coverage, in addition to MC-based B0 field shimming, for robust human brain proton MRSI.In vivo experiments demonstrate that MC-ECLIPSE allows axial brain coverage of 92–95 % is achieved following arbitrary ROI shaped OVS for various head shapes. The standard deviation (SD) of the residual B0 field following SH2 and MC shimming were 25 ± 9 Hz and 18 ± 8 Hz over a 5 cm slab, and 18 ± 5 Hz and 14 ± 6 Hz over a 1.5 cm slab, respectively. These results demonstrate that B0 magnetic field shimming with the MC array supersedes second order harmonic capabilities available on standard MRI systems for both restricted and large ROIs. Furthermore, MC based B0 shimming provides comparable shimming performance to an unrestricted SH5 shim set for both restricted, and 5-cm slab shim challenges.Phantom experiments demonstrate the high level of localization performance achievable with MC-ECLIPSE, with ROI edge chemical shift displacements ranging from 1–3 mm with a median value of 2 mm, and transition width metrics ranging from 1–2.5 mm throughout the ROI edge. Furthermore, MC based B0 shimming is comparable to performance following a full set of unrestricted spherical harmonic fields up to order 5. Short echo time MRSI and GABA-edited MRSI acquisitions in the human brain following MC-shimming and arbitrary ROI shaping demonstrate full-axial slice coverage and extracranial lipid artifact free spectra. MC-ECLIPSE allows full-axial coverage and robust MRSI acquisitions, while allowing interrogation of cortical tissue proximal to the skull, which has significant value in a wide range of neurological and psychiatric conditions.
- Published
- 2024
- Full Text
- View/download PDF
200. Interchromosomal segmental duplication drives translocation and loss of P. falciparum histidine-rich protein 3
- Author
-
Nicholas J Hathaway, Isaac E Kim, Neeva WernsmanYoung, Sin Ting Hui, Rebecca Crudale, Emily Y Liang, Christian P Nixon, David Giesbrecht, Jonathan J Juliano, Jonathan B Parr, and Jeffrey A Bailey
- Subjects
non-allelic homologous recombination ,segmental duplication ,rapid diagnostic tests ,nanopore sequencing ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Most malaria rapid diagnostic tests (RDTs) detect Plasmodium falciparum histidine-rich protein 2 (PfHRP2) and PfHRP3, but deletions of pfhrp2 and phfrp3 genes make parasites undetectable by RDTs. We analyzed 19,313 public whole-genome-sequenced P. falciparum field samples to understand these deletions better. Pfhrp2 deletion only occurred by chromosomal breakage with subsequent telomere healing. Pfhrp3 deletions involved loss from pfhrp3 to the telomere and showed three patterns: no other associated rearrangement with evidence of telomere healing at breakpoint (Asia; Pattern 13-TARE1); associated with duplication of a chromosome 5 segment containing multidrug-resistant-1 gene (Asia; Pattern 13-5++); and most commonly, associated with duplication of a chromosome 11 segment (Americas/Africa; Pattern 13-11++). We confirmed a 13–11 hybrid chromosome with long-read sequencing, consistent with a translocation product arising from recombination between large interchromosomal ribosome-containing segmental duplications. Within most 13-11++ parasites, the duplicated chromosome 11 segments were identical. Across parasites, multiple distinct haplotype groupings were consistent with emergence due to clonal expansion of progeny from intrastrain meiotic recombination. Together, these observations suggest negative selection normally removes 13-11++pfhrp3 deletions, and specific conditions are needed for their emergence and spread including low transmission, findings that can help refine surveillance strategies.
- Published
- 2024
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.