Search

Your search keyword '"Bang D"' showing total 876 results
Start Over Author "Bang D"
876 results on '"Bang D"'

1. Toward Spectrum Coexistence: First Demonstration of the Effectiveness of Boresight Avoidance between the NRAO Green Bank Telescope and Starlink Satellites

Author

Bang D. Nhan, Christopher G. De Pree, Matt Iverson, Brenne Gregory, Daniel Dueri, Anthony Beasley, and Brian Schepis

Subjects
Observational astronomy, Artificial satellites, Radio astronomy, Microwave spectroscopy, Polarimetry, Single-dish antennas, Astrophysics, QB460-466
Abstract

NRAO and SpaceX have been engaged in coordinated testing efforts since Fall 2021, including conducting experiments on different interference avoidance schemes for the Karl G. Jansky Very Large Array in New Mexico, and the Green Bank Telescope (GBT) inside the National Radio Quiet Zone in West Virginia. The Starlink system is capable of avoiding direct illumination of telescope sites with their adaptive tasking to place downlink beams far away. Nevertheless, even satellites operating in this mode can potentially present strong signals into the telescope’s receiver system if they pass close to the telescope’s main beam at the boresight. For additional protection, Starlink satellites can either momentarily redirect or completely disable their downlink channels while they pass within some minimum angular separation threshold from the telescope’s boresight, methods that are referred to as “telescope boresight avoidance.” In two separate experiments conducted since Fall 2023, NRAO and SpaceX arranged to have the GBT observe a fixed R.A./decl. position in the sky, chosen to have a large number of close-to-boresight Starlink passages. Preliminary analysis from these two experiments illustrates the feasibility of these avoidance methods to significantly reduce, if not eliminate, the negative impact of close-to-boresight satellite passages. Importantly, these experiments demonstrate the value of continuing cooperative efforts between NRAO and SpaceX, and expanding cooperation between the radio astronomy and satellite communities more generally.

Published
2024
Full Text
View/download PDF

2. MEDEA: A New Model for Emulating Radio Antenna Beam Patterns for 21 cm Cosmology and Antenna Design Studies

Author

Joshua J. Hibbard, Bang D. Nhan, David Rapetti, and Jack O. Burns

Subjects
H I line emission, Radio astronomy, Radio interferometers, Radio observatories, Radio telescopes, Single-dish antennas, Astrophysics, QB460-466
Abstract

In 21 cm experimental cosmology, accurate characterization of a radio telescope’s antenna beam response is essential to measure the 21 cm signal. Computational electromagnetic (CEM) simulations estimate the antenna beam pattern and frequency response by subjecting the EM model to different dependencies, or beam hyperparameters, such as soil dielectric constant or orientation with the environment. However, it is computationally expensive to search all possible parameter spaces to optimize the antenna design or accurately represent the beam to the level required for use as a systematic model in 21 cm cosmology. We therefore present the Model for Emulating Directivities and Electric fields of Antennas ( MEDEA) , an emulator that rapidly and accurately generates far-field radiation patterns over a large hyperparameter space. MEDEA takes a subset of beams simulated by CEM software, spatially decomposes them into coefficients on a complete, linear basis, and then interpolates them to form new beams at arbitrary hyperparameters. We test MEDEA on an analytical dipole and two numerical beams motivated by upcoming lunar lander missions, and then employ MEDEA as a model to fit mock radio spectrometer data to extract covariances on the input beam hyperparameters. We find that the interpolated beams have rms relative errors of at most 10 ^−2 using 20 input beams or less, and that fits to mock data are able to recover the input beam hyperparameters when the model and mock are derived from the same set of beams. When a systematic bias is introduced into the mock data, extracted beam hyperparameters exhibit bias, as expected. We propose several extensions to MEDEA to potentially account for such bias.

Published
2024
Full Text
View/download PDF

3. ODS: A self-reporting system for radio telescopes to coexist with adaptive satellite constellations

Author

Nhan, Bang D., De Pree, Christopher G., Beasley, Anthony, Whitehead, Mark, Ryan, Kevin, Faes, Daniel, Chamberlin, Thomas, Pattison, Dawn, Catlett, Victoria, Lawson, Aaron, Bautista, Daniel, Wasik, Sheldon, Dueri, Daniel, Iverson, Matt, Donenfeld, Jacob, Schepis, Brian, and Goldstein, David

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

Low Earth orbit (LEO) satellite constellations bring broadband internet and cellular service to the most remote locations on the planet. Unfortunately, many of these locations also host some of the world's best optical and radio astronomy (RA) observatories. With the number of LEO satellites expected to increase by an order of magnitude in the upcoming decade, satellite downlink radio frequency interference (RFI) is a growing concern in protected radio-quiet areas like the United States National Radio Quiet Zone. When these satellites transmit in the spectrum near protected RA bands, undesired out-of-band emission can leak into these protected bands and impact scientific observations. In this paper, we present a self-reporting system - Operational Data Sharing (ODS) - which enables mutual awareness by publishing radio telescopes' operational information to a protected database that is available to satellite operators through a representational state transfer application programming interface (REST API). Satellite operators can use the ODS data to adapt their downlink tasking algorithms in real time to avoid overwhelming sensitive RA facilities, particularly, through the novel Telescope Boresight Avoidance (TBA) technique. Preliminary results from recent experiments between the NRAO and the SpaceX Starlink teams demonstrate the effectiveness of the ODS and TBA in reducing downlink RFI in the Karl G. Jansky Very Large Array's observations in the 1990-1995 MHz and 10.7-12.7 GHz bands. This automated ODS system is beginning to be implemented by other RA facilities and could be utilized by other satellite operators in the near future., Comment: 9 pages, 6 figures, draft version, submitted for review to the Astrophysical Journal Letters (ApJL) on 20 Feb 2025

Published
2025

4. Domain-specific NLP system to support learning path and curriculum design at tech universities

Author

Nhi N.Y. Vo, Quang T. Vu, Nam H. Vu, Tu A. Vu, Bang D. Mach, and Guandong Xu

Subjects
Data science applications in education, Architectures for educational technology system, Teaching/learning strategies, Electronic computers. Computer science, QA75.5-76.95
Abstract

The tech sector has been growing at a rapid speed, demanding a higher level of expertise from its labor force. New skills and programming languages are introduced and required by the industry every day, while the university courses are not updated adequately. Finding the high-demand skills and relevant courses to study has become essential to both students and faculty members at tech universities, which leads to a growing research interest in building an intelligence system to support decision making. Leveraging recent development in Natural Language Processing, we built an NLP-based course recommendation system specifically for the computer science (CS) and information technology (IT) fields. In particular, we built (1) a Named Entity Recognition (CSIT-NER) model to extract tech-related skills and entities, then used these skills to build (2) a personalized multi-level course recommendation system using a hybrid model (hybrid CSIT-CRS). Our CSIT-NER model, trained and fine-tuned on a large corpus of text extracted from StackOverflow and GitHub, can accurately extract the relevant skills and entities, outperforming state-of-the-art models across all evaluation metrics. Our hybrid CSIT-CRS can provide recommendations on multiple individualized levels of university courses, career paths with job listings, and industry-required with suitable online courses. The whole system received good ratings and feedback from users from our survey with 201 volunteers who are students and faculty members of tech universities in Australia and Vietnam. This research is beneficial to students, faculty members, universities in CS/IT higher education sector, and stakeholders in tech-related industries.

Published
2022
Full Text
View/download PDF

5. Constraining a Model of the Radio Sky below 6 MHz Using the Parker Solar Probe/FIELDS Instrument in Preparation for Upcoming Lunar-based Experiments

Author

Neil Bassett, David Rapetti, Bang D. Nhan, Brent Page, Jack O. Burns, Marc Pulupa, and Stuart D. Bale

Subjects
Radio astronomy, Astronomy data analysis, Bayesian statistics, Nested sampling, Cosmology, Interstellar synchrotron emission, Astrophysics, QB460-466
Abstract

We present a Bayesian analysis of data from the FIELDS instrument on board the Parker Solar Probe (PSP) spacecraft with the aim of constraining low-frequency (≲6 MHz) sky in preparation for several upcoming lunar-based experiments. We utilize data recorded during PSP’s coning roll maneuvers, in which the axis of the spacecraft is pointed 45° off of the Sun. The spacecraft then rotates about a line between the Sun and the spacecraft with a period of 24 minutes. We reduce the data into two formats: roll-averaged, in which the spectra are averaged over the roll, and phase-binned, in which the spectra are binned according to the phase of the roll. We construct a forward model of the FIELDS observations that includes numerical simulations of the antenna beam, an analytic emissivity function of the galaxy, and estimates of the absorption due to free electrons. Fitting 5 parameters, we find that the roll-averaged data can be fit well by this model, and we obtain posterior parameter constraints that are in general agreement with previous estimates. The model is not, however, able to fit the phase-binned data well, likely due to limitations such as the lack of nonsmooth emission structure at both small and large scales, enforced symmetry between the northern and southern galactic hemispheres, and large uncertainties in the free electron density. This suggests that significant improvement in the low-frequency sky model is needed in order to fully and accurately represent the sky at frequencies below 6 MHz.

Published
2023
Full Text
View/download PDF

6. The Impact of Beam Variations on Power Spectrum Estimation for 21 cm Cosmology. II. Mitigation of Foreground Systematics for HERA

Author

Honggeun Kim, Nicholas S. Kern, Jacqueline N. Hewitt, Bang D. Nhan, Joshua S. Dillon, Eloy de Lera Acedo, Scott B. C. Dynes, Nivedita Mahesh, Nicolas Fagnoni, and David R. DeBoer

Subjects
Cosmology, Reionization, Radio astronomy, Radio interferometers, Astronomical instrumentation, Astrophysics, QB460-466
Abstract

One key challenge in detecting a 21 cm cosmological signal at z > 6 is to separate the cosmological signal from foreground emission. This can be studied in a power spectrum space where the foreground is confined to low delay (or, equivalently, k _∥ ) modes, whereas the cosmological signal can spread out to high delay modes. When there is a calibration error, however, the chromaticity of the gain errors propagates to the power spectrum estimate and contaminates the modes for cosmological detection. The Hydrogen Epoch of Reionization Array (HERA) employs a high-precision calibration scheme using redundancy in measurements. In this study, we focus on the gain errors induced by nonredundancies arising from a feed offset relative to HERA’s 14 m parabolic dish element and investigate how to mitigate the chromatic gain errors using three different methods: restricting baseline lengths for calibration, smoothing the antenna gains, and applying a temporal filter prior to calibration. With 2 cm/2° perturbations for translation/tilting motions, a level achievable under normal HERA operating conditions, the combination of the baseline cut and temporal filtering indicates that the spurious gain feature due to nonredundancies is significantly reduced, and the power spectrum recovers the clean foreground-free region. We found that the mitigation technique works even for large feed motions, but in order to keep a stable calibration process, the feed positions need to be constrained to 2 cm for translation motions and 2° for tilting offset relative to the dish’s vertex.

Published
2023
Full Text
View/download PDF

7. $\texttt{MEDEA}$: A New Model for Emulating Radio Antenna Beam Patterns for 21-cm Cosmology and Antenna Design Studies

Author

Hibbard, Joshua J., Nhan, Bang D., Rapetti, David, and Burns, Jack O.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

In 21-cm experimental cosmology, accurate characterization of a radio telescope's antenna beam response is essential to measure the 21-cm signal. Computational electromagnetic (CEM) simulations estimate the antenna beam pattern and frequency response by subjecting the EM model to different dependencies, or beam hyper-parameters, such as soil dielectric constant or orientation with the environment. However, it is computationally expensive to search all possible parameter spaces to optimize the antenna design or accurately represent the beam to the level required for use as a systematic model in 21-cm cosmology. We therefore present $\texttt{MEDEA}$, an emulator which rapidly and accurately generates farfield radiation patterns over a large hyper-parameter space. $\texttt{MEDEA}$ takes a subset of beams simulated by CEM software, spatially decomposes them into coefficients in a complete, linear basis, and then interpolates them to form new beams at arbitrary hyper-parameters. We test $\texttt{MEDEA}$ on an analytical dipole and two numerical beams motivated by upcoming lunar lander missions, and then employ $\texttt{MEDEA}$ as a model to fit mock radio spectrometer data to extract covariances on the input beam hyper-parameters. We find that the interpolated beams have RMS relative errors of at most $10^{-2}$ using 20 input beams or less, and that fits to mock data are able to recover the input beam hyper-parameters when the model and mock derive from the same set of beams. When a systematic bias is introduced into the mock data, extracted beam hyper-parameters exhibit bias, as expected. We propose several future extensions to $\texttt{MEDEA}$ to potentially account for such bias., Comment: 23 pages, 12 figures, accepted for publication in ApJ

Published
2024

8. Toward Spectrum Coexistence: First Demonstration of the Effectiveness of Boresight Avoidance between the NRAO Green Bank Telescope and Starlink Satellites

Author

Nhan, Bang D., De Pree, Christopher G., Iverson, Matt, Gregory, Brenne, Dueri, Daniel, Beasley, Anthony, and Schepis, Brian

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

NRAO and SpaceX have been engaged in coordinated testing efforts since Fall 2021, including conducting experiments on different interference avoidance schemes for the Karl G. Jansky Very Large Array (VLA) in New Mexico, and the Green Bank Telescope (GBT) inside the National Radio Quiet Zone (NRQZ) in West Virginia. The Starlink system is capable of avoiding direct illumination of telescope sites with their adaptive tasking to place downlink beams far away. Nevertheless, even satellites operating in this mode can potentially present strong signals into the telescope's receiver system if they pass close to the telescope's main beam at the boresight. For additional protection, Starlink satellites can either momentarily redirect or completely disable their downlink channels while they pass within some minimum angular separation threshold from the telescope's boresight, methods that are referred to as "telescope boresight avoidance". In two separate experiments conducted since Fall 2023, NRAO and SpaceX arranged to have the GBT observe a fixed RA/Dec position in the sky, chosen to have a large number of close-to-boresight Starlink passages. Preliminary analysis from these two experiments illustrate the feasibility of these avoidance methods to significantly reduce, if not eliminate, the negative impact of close-to-boresight satellite passages. Importantly, these experiments demonstrate the value of continuing cooperative efforts between NRAO and SpaceX, and expanding cooperation between the radio astronomy and satellite communities more generally., Comment: 10 pages, 5 figures, Accepted for publication by Astrophysical Journal Letters (31 Jul 2024)

Published
2024

9. The Impact of Beam Variations on Power Spectrum Estimation for 21 cm Cosmology II: Mitigation of Foreground Systematics for HERA

Author

Kim, Honggeun, Kern, Nicholas S., Hewitt, Jacqueline N., Nhan, Bang D., Dillon, Joshua S., Acedo, Eloy de Lera, Dynes, Scott B. C., Mahesh, Nivedita, Fagnoni, Nicolas, and DeBoer, David R.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

One key challenge in detecting 21 cm cosmological signal at z > 6 is to separate the cosmological signal from foreground emission. This can be studied in a power spectrum space where the foreground is confined to low delay modes whereas the cosmological signal can spread out to high delay modes. When there is a calibration error, however, chromaticity of gain errors propagates to the power spectrum estimate and contaminates the modes for cosmological detection. The Hydrogen Epoch of Reionization Array (HERA) employs a high-precision calibration scheme using redundancy in measurements. In this study, we focus on the gain errors induced by nonredundancies arising from feed offset relative to the HERA's 14 meter parabolic dish element, and investigate how to mitigate the chromatic gain errors using three different methods: restricting baseline lengths for calibration, smoothing the antenna gains, and applying a temporal filter prior to calibration. With 2 cm/2 degree perturbations for translation/tilting motions, a level achievable under normal HERA operating conditions, the combination of the baseline cut and temporal filtering indicates that the spurious gain feature due to nonredundancies is significantly reduced, and the power spectrum recovers the clean foreground-free region. We found that the mitigation technique works even for large feed motions but in order to keep a stable calibration process, the feed positions need to be constrained to 2 cm for translation motions and 2 degree for tilting offset relative to the dish's vertex., Comment: Accepted for publication in ApJ

Published
2023

11. The Impact of Beam Variations on Power Spectrum Estimation for 21-cm Cosmology I: Simulations of Foreground Contamination for HERA

Author

Kim, Honggeun, Nhan, Bang D., Hewitt, Jacqueline N., Kern, Nicholas S., Dillon, Joshua S., Acedo, Eloy de Lera, Dynes, Scott, Mahesh, Nivedita, Fagnoni, Nicolas, and DeBoer, David R.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Detecting cosmological signals from the Epoch of Reionization (EoR) requires high-precision calibration to isolate the cosmological signals from foreground emission. In radio interferometery, perturbed primary beams of antenna elements can disrupt the precise calibration, which results in contaminating the foreground-free region, or the EoR window, in the cylindrically averaged power spectrum. For Hydrogen Epoch of Reionization Array (HERA), we simulate and characterize the perturbed primary beams induced by feed motions such as axial, lateral, and tilting motions, above the 14-meter dish. To understand the effect of the perturbed beams, visibility measurements are modeled with two different foreground components, point sources and diffuse sources, and we find different feed motions present a different reaction to each type of sky source. HERA's redundant-baseline calibration in the presence of non-redundant antenna beams due to feed motions introduces chromatic errors in gain solutions, which produces foreground power leakage into the EoR window. The observed leakage from vertical feed motions comes predominately from point sources around zenith. Furthermore, the observed leakage from horizontal and tilting feed motion comes predominately from the diffuse components near the horizon. Mitigation of chromatic gain errors will be necessary for robust detection of the EoR signals with minimal foreground bias, and this will be discussed in the subsequent paper., Comment: Accepted for publication in ApJ

Published
2022
Full Text
View/download PDF

13. Lost Horizon: Quantifying the Effect of Local Topography on Global 21-cm Cosmology Data Analysis

Author

Bassett, Neil, Rapetti, David, Tauscher, Keith, Nhan, Bang D., Bordenave, David D., Hibbard, Joshua J., and Burns, Jack O.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We present an investigation of the horizon and its effect on global 21-cm observations and analysis. We find that the horizon cannot be ignored when modeling low frequency observations. Even if the sky and antenna beam are known exactly, forward models cannot fully describe the beam-weighted foreground component without accurate knowledge of the horizon. When fitting data to extract the 21-cm signal, a single time-averaged spectrum or independent multi-spectrum fits may be able to compensate for the bias imposed by the horizon. However, these types of fits lack constraining power on the 21-cm signal, leading to large uncertainties on the signal extraction, in some cases larger in magnitude than the 21-cm signal itself. A significant decrease in signal uncertainty can be achieved by performing multi-spectrum fits in which the spectra are modeled simultaneously with common parameters. The cost of this greatly increased constraining power, however, is that the time dependence of the horizon's effect, which is more complex than its spectral dependence, must be precisely modeled to achieve a good fit. To aid in modeling the horizon, we present an algorithm and Python package for calculating the horizon profile from a given observation site using elevation data. We also address several practical concerns such as pixelization error, uncertainty in the horizon profile, and foreground obstructions such as surrounding buildings and vegetation. We demonstrate that our training set-based analysis pipeline can account for all of these factors to model the horizon well enough to precisely extract the 21-cm signal from simulated observations., Comment: 19 pages, 11 figures, 1 table

Published
2021
Full Text
View/download PDF

14. Global 21-cm signal extraction from foreground and instrumental effects IV: Accounting for realistic instrument uncertainties and their overlap with foreground and signal models

Author

Tauscher, Keith, Rapetti, David, Nhan, Bang D., Handy, Alec, Bassett, Neil, Hibbard, Joshua, Bordenave, David, Bradley, Richard F., and Burns, Jack O.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

All 21-cm signal experiments rely on electronic receivers that affect the data via both multiplicative and additive biases through the receiver's gain and noise temperature. While experiments attempt to remove these biases, the residuals of their imperfect calibration techniques can still confuse signal extraction algorithms. In this paper, the fourth and final installment of our pipeline series, we present a technique for fitting out receiver effects as efficiently as possible. The fact that the gain and global signal, which are multiplied in the observation equation, must both be modeled implies that the model of the data is nonlinear in its parameters, making numerical sampling the only way to explore the parameter distribution rigorously. However, multi-spectra fits, which are necessary to extract the signal confidently as demonstrated in the third paper of the series, often require large numbers of foreground parameters, increasing the dimension of the posterior distribution that must be explored and therefore causing numerical sampling inefficiencies. Building upon techniques in the second paper of the series, we outline a method to explore the full parameter distribution by numerically sampling a small subset of the parameters and analytically marginalizing over the others. We test this method in simulation using a type-I Chebyshev band-pass filter gain model and a fast signal model based on a spline between local extrema. The method works efficiently, converging quickly to the posterior signal parameter distribution. The final signal uncertainties are of the same order as the noise in the data., Comment: 15 pages, 7 figures, submitted to ApJ

Published
2021
Full Text
View/download PDF

17. Assessment of the Projection-induced Polarimetry Technique for Constraining the Foreground Spectrum in Global 21 cm Cosmology

Author

Nhan, Bang D., Bordenave, David D., Bradley, Richard F., Burns, Jack O., Tauscher, Keith, Rapetti, David, and Klima, Patricia J.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Detecting the cosmological sky-averaged (global) 21 cm signal as a function of observed frequency will provide a powerful tool to study the ionization and thermal history of the intergalactic medium (IGM) in the early Universe ($\sim$ 400 million years after the Big Bang). The greatest challenge in conventional total-power global 21 cm experiments is the removal of the foreground synchrotron emission ($\sim 10^3$-$10^4$ K) to uncover the weak cosmological signal (tens to hundreds of mK), especially since the intrinsic smoothness of the foreground spectrum is corrupted by instrumental effects. Although the EDGES team has recently reported an absorption profile at 78 MHz in the sky-averaged spectrum, it is necessary to confirm this detection with an independent approach. The projection effect from observing anisotropic foreground source emission with a wide-view antenna pointing at the North Celestial Pole (NCP) can induce a net polarization, referred as the Projection-Induced Polarization Effect (PIPE). Due to Earth's rotation, observation centered at the circumpolar region will impose a dynamic sky modulation on the net polarization's waveforms which is unique to the foreground component. In this study, we review the implementation practicality and underlying instrumental effects of this new polarimetry-based technique with detailed numerical simulation and a testbed instrument, the Cosmic Twilight Polarimeter (CTP). In addition, we explore an SVD-based analysis approach for separating the foreground and instrumental effects from the background global 21 cm signal using the sky-modulated PIPE., Comment: 19 pages, 24 figures, 1 table, accepted by ApJ

Published
2018
Full Text
View/download PDF

20. A polarimetric approach for constraining the dynamic foreground spectrum for cosmological global 21-cm measurements

Author

Nhan, Bang D., Bradley, Richard F., and Burns, Jack O.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The cosmological global (sky-averaged) 21-cm signal is a powerful tool to probe the evolution of the intergalactic medium (IGM) in high-redshift Universe ($z \leq 6$). One of the biggest observational challenges is to remove the foreground spectrum which is at least four orders of magnitude brighter than the cosmological 21-cm emission. Conventional global 21-cm experiments rely on the spectral smoothness of the foreground synchrotron emission to separate it from the unique 21-cm spectral structures in a single total-power spectrum. However, frequency-dependent instrumental and observational effects are known to corrupt such smoothness and complicates the foreground subtraction. We introduce a polarimetric approach to measure the projection-induced polarization of the anisotropic foreground onto a stationary dual-polarized antenna. Due to Earth rotation, when pointing the antenna at a celestial pole, the revolving foreground will modulate this polarization with a unique frequency-dependent sinusoidal signature as a function of time. In our simulations, by harmonic decomposing this dynamic polarization, our technique produces two separate spectra in parallel from the same observation: (i) a total sky power consisting both the foreground and the 21-cm background, (ii) a model-independent measurement of the foreground spectrum at a harmonic consistent to twice the sky rotation rate. In the absence of any instrumental effects, by scaling and subtracting the latter from the former, we recover the injected global 21-cm model within assumed uncertainty. We further discuss several limiting factors and potential remedies for future implementation., Comment: 16 pages, 22 figures, 2 tables. Accepted to The Astrophysical Journal. This is the final version after addressing referee's comments

Published
2016
Full Text
View/download PDF

23. Long COVID research: an update from the PHOSP-COVID Scientific Summit

Author

Brightling, Christopher E, primary, Evans, Rachael A, additional, Singapuri, Amisha, additional, Smith, Nikki, additional, Wain, Louise V, additional, Brightling, C E, additional, Evans, R A, additional, Wain, L V, additional, Chalmers, J D, additional, Harris, V C, additional, Ho, L P, additional, Horsley, A, additional, Houchen-Wolloff, L, additional, Marks, M, additional, Raman, B, additional, Singapuri, A, additional, Barran, P, additional, Bingham, M, additional, Chilvers, E R, additional, Daynes, E, additional, Efstathiou, C M, additional, Elneima, O, additional, Guillen Guio, B, additional, Harrison, E M, additional, Jenkins, R G, additional, Liew, F, additional, Lone, N I, additional, Lord, J M, additional, McAuley, H J C, additional, McCann, G P, additional, Mitchell, J, additional, Plekhanova, T, additional, Russell, R J, additional, Saunders, R M, additional, Semple, M G, additional, Smith, N, additional, Trivedi, D, additional, Turtle, L, additional, Walker, S, additional, Abel, K, additional, Adamali, H, additional, Adeloye, D, additional, Adeyemi, O, additional, Adrego, R, additional, Aguilar Jimenez, L A, additional, Ahmad, S, additional, Ahmad Haider, N, additional, Ahmed, R, additional, Ahwireng, N, additional, Ainsworth, M, additional, Al-Sheklly, B, additional, Alamoudi, A, additional, Ali, M, additional, Aljaroof, M, additional, Allan, L, additional, Allen, R J, additional, Allerton, L, additional, Allsop, L, additional, Allt, AM, additional, Almeida, P, additional, Altmann, D, additional, Alvarez Corral, M, additional, Amoils, S, additional, Anderson, D, additional, Antoniades, C, additional, Arbane, G, additional, Arias, A, additional, Armour, C, additional, Armstrong, L, additional, Armstrong, N, additional, Arnold, D, additional, Arnold, H, additional, Ashish, A, additional, Ashworth, A, additional, Ashworth, M, additional, Aslani, S, additional, Assefa-Kebede, H, additional, Atkin, P, additional, Atkin, C, additional, Aul, R, additional, Aung, H, additional, Austin, L, additional, Avram, C, additional, Ayoub, A, additional, Babores, M, additional, Baggott, R, additional, Bagshaw, J, additional, Baguley, D, additional, Bailey, L, additional, Baillie, J K, additional, Bain, S, additional, Bakali, M, additional, Bakau, M, additional, Baldry, E, additional, Baldwin, M, additional, Baldwin, D, additional, Ballard, C, additional, Banerjee, A, additional, Bang, D, additional, Barker, R E, additional, Barman, L, additional, Barratt, S, additional, Barrett, F, additional, Basire, D, additional, Basu, N, additional, Bates, M, additional, Bates, A, additional, Batterham, R, additional, Baxendale, H, additional, Baxter, G, additional, Bayes, H, additional, Beadsworth, M, additional, Beckett, P, additional, Beggs, M, additional, Begum, M, additional, Beirne, P, additional, Bell, M, additional, Bell, R, additional, Bennett, K, additional, Beranova, E, additional, Bermperi, A, additional, Berridge, A, additional, Berry, C, additional, Betts, S, additional, Bevan, E, additional, Bhui, K, additional, Birchall, K, additional, Bishop, L, additional, Bisnauthsing, K, additional, Blaikely, J, additional, Bloss, A, additional, Bolger, A, additional, Bolton, C E, additional, Bonnington, J, additional, Botkai, A, additional, Bourne, C, additional, Bourne, M, additional, Bramham, K, additional, Brear, L, additional, Breen, G, additional, Breeze, J, additional, Breeze, K, additional, Briggs, A, additional, Bright, E, additional, Brill, S, additional, Brindle, K, additional, Broad, L, additional, Broadley, A, additional, Brookes, C, additional, Broome, M, additional, Brown, V, additional, Brown, M, additional, Brown, J, additional, Brown, A, additional, Brown, J S, additional, Brugha, T, additional, Brunskill, N, additional, Buch, M, additional, Buckley, P, additional, Bularga, A, additional, Bullmore, E, additional, Bunker, J, additional, Burden, L, additional, Burdett, T, additional, Burn, D, additional, Burns, G, additional, Burns, A, additional, Busby, J, additional, Butcher, R, additional, Butt, A, additional, Byrne, S, additional, Cairns, P, additional, Calder, P C, additional, Calvelo, E, additional, Carborn, H, additional, Card, B, additional, Carr, C, additional, Carr, L, additional, Carson, G, additional, Carter, P, additional, Casey, A, additional, Cassar, M, additional, Cavanagh, J, additional, Chablani, M, additional, Chalder, T, additional, Chambers, R C, additional, Chan, F, additional, Channon, K M, additional, Chapman, K, additional, Charalambou, A, additional, Chaudhuri, N, additional, Checkley, A, additional, Chen, J, additional, Cheng, Y, additional, Chetham, L, additional, Childs, C, additional, Chinoy, H, additional, Chiribiri, A, additional, Chong-James, K, additional, Choudhury, N, additional, Choudhury, G, additional, Chowienczyk, P, additional, Christie, C, additional, Chrystal, M, additional, Clark, C, additional, Clark, D, additional, Clarke, J, additional, Clohisey, S, additional, Coakley, G, additional, Coburn, Z, additional, Coetzee, S, additional, Cole, J, additional, Coleman, C, additional, Conneh, F, additional, Connell, D, additional, Connolly, B, additional, Connor, L, additional, Cook, A, additional, Cooper, S, additional, Cooper, B, additional, Cooper, J, additional, Copeland, D, additional, Cosier, T, additional, Coulding, M, additional, Coupland, C, additional, Cox, E, additional, Craig, T, additional, Crisp, P, additional, Cristiano, D, additional, Crooks, M G, additional, Cross, A, additional, Cruz, I, additional, Cullinan, P, additional, Cuthbertson, D, additional, Daines, L, additional, Dalton, M, additional, Daly, P, additional, Daniels, A, additional, Dark, P, additional, Dasgin, J, additional, David, C, additional, David, A, additional, Davies, F, additional, Davies, E, additional, Davies, K, additional, Davies, G, additional, Davies, G A, additional, Davies, M J, additional, Dawson, J, additional, Dawson, C, additional, De Soyza, A, additional, Deakin, B, additional, Deans, A, additional, Deas, C, additional, Deery, J, additional, Defres, S, additional, Dell, A, additional, Dempsey, K, additional, Denneny, E, additional, Dennis, J, additional, Dewar, A, additional, Dharmagunawardena, R, additional, Diar-Bakerly, N, additional, Dickens, C, additional, Dipper, A, additional, Diver, S, additional, Diwanji, S N, additional, Dixon, M, additional, Djukanovic, R, additional, Dobson, H, additional, Dobson, S L, additional, Docherty, A B, additional, Donaldson, A, additional, Dong, T, additional, Dormand, N, additional, Dougherty, A, additional, Dowling, R, additional, Drain, S, additional, Draxlbauer, K, additional, Drury, K, additional, Dulawan, P, additional, Dunleavy, A, additional, Dunn, S, additional, Dupont, C, additional, Earley, J, additional, Easom, N, additional, Echevarria, C, additional, Edwards, S, additional, Edwardson, C, additional, El-Taweel, H, additional, Elliott, A, additional, Elliott, K, additional, Ellis, Y, additional, Elmer, A, additional, Evans, T, additional, Evans, R I, additional, Evans, D, additional, Evans, R, additional, Evans, H, additional, Evans, J, additional, Evenden, C, additional, Evison, L, additional, Fabbri, L, additional, Fairbairn, S, additional, Fairman, A, additional, Fallon, K, additional, Faluyi, D, additional, Favager, C, additional, Fayzan, T, additional, Featherstone, J, additional, Felton, T, additional, Ferreira, V, additional, Finch, J, additional, Finney, S, additional, Finnigan, J, additional, Finnigan, L, additional, Fisher, H, additional, Fletcher, S, additional, Flockton, R, additional, Flynn, M, additional, Foot, H, additional, Foote, D, additional, Ford, A, additional, Forton, D, additional, Fraile, E, additional, Francis, C, additional, Francis, R, additional, Francis, S, additional, Frankel, A, additional, Fraser, E, additional, Free, R, additional, French, N, additional, Fu, X, additional, Fuld, J, additional, Furniss, J, additional, Garner, L, additional, Gautam, N, additional, Geddes, J R, additional, George, J, additional, George, P, additional, Gibbons, M, additional, Gill, R, additional, Gill, M, additional, Gilmour, L, additional, Gleeson, F, additional, Glossop, J, additional, Glover, S, additional, Goodman, N, additional, Goodwin, C, additional, Gooptu, B, additional, Gordon, H, additional, Gorsuch, T, additional, Greatorex, M, additional, Greenhaff, P L, additional, Greenhalf, W, additional, Greenhalgh, A, additional, Greening, N J, additional, Greenwood, J, additional, Gregory, R, additional, Gregory, H, additional, Grieve, D, additional, Griffin, D, additional, Griffiths, L, additional, Guerdette, A-M, additional, Gummadi, M, additional, Gupta, A, additional, Gurram, S, additional, Guthrie, E, additional, Guy, Z, additional, Hadley, K, additional, Haggar, A, additional, Hainey, K, additional, Hairsine, B, additional, Haldar, P, additional, Hall, L, additional, Hall, I, additional, Halling-Brown, M, additional, Hamil, R, additional, Hancock, A, additional, Hancock, K, additional, Hanley, N A, additional, Haq, S, additional, Hardwick, H E, additional, Hardy, T, additional, Hardy, E, additional, Hargadon, B, additional, Harrington, K, additional, Harris, E, additional, Harrison, P, additional, Hart, N, additional, Harvey, A, additional, Harvey, M, additional, Harvie, M, additional, Haslam, L, additional, Hastie, C, additional, Havinden-Williams, M, additional, Hawkes, J, additional, Hawkings, N, additional, Haworth, J, additional, Hayday, A, additional, Haynes, M, additional, Hazeldine, J, additional, Hazelton, T, additional, Heaney, L G, additional, Heeley, C, additional, Heeney, J L, additional, Heightman, M, additional, Heller, S, additional, Henderson, M, additional, Henson, H, additional, Hesselden, L, additional, Hewitt, M, additional, Highett, V, additional, Hillman, T, additional, Hiwot, T, additional, Hoare, M, additional, Hoare, A, additional, Hockridge, J, additional, Hogarth, P, additional, Holbourn, A, additional, Holden, S, additional, Holdsworth, L, additional, Holgate, D, additional, Holland, M, additional, Holloway, L, additional, Holmes, K, additional, Holmes, M, additional, Holroyd-Hind, B, additional, Holt, L, additional, Hormis, A, additional, Hosseini, A, additional, Hotopf, M, additional, Howard, L S, additional, Howard, K, additional, Howell, A, additional, Hufton, E, additional, Hughes, R A, additional, Hughes, J, additional, Hughes, A D, additional, Humphries, A, additional, Huneke, N, additional, Hurditch, E, additional, Hurst, J, additional, Husain, M, additional, Hussell, T, additional, Hutchinson, J, additional, Ibrahim, W, additional, Ilyas, F, additional, Ingham, J, additional, Ingram, L, additional, Ionita, D, additional, Isaacs, K, additional, Ismail, K, additional, Jackson, T, additional, Jacob, J, additional, James, W Y, additional, Jang, W, additional, Jarman, C, additional, Jarrold, I, additional, Jarvis, H, additional, Jastrub, R, additional, Jayaraman, B, additional, Jezzard, P, additional, Jiwa, K, additional, Johnson, C, additional, Johnson, S, additional, Johnston, D, additional, Jolley, C J, additional, Jones, S, additional, Jones, H, additional, Jones, L, additional, Jones, I, additional, Jones, G, additional, Jones, M G, additional, Jones, D, additional, Jose, S, additional, Kabir, T, additional, Kaltsakas, G, additional, Kamwa, V, additional, Kanellakis, N, additional, Kaprowska, S, additional, Kausar, Z, additional, Keenan, N, additional, Kelly, S, additional, Kemp, G, additional, Kerr, S, additional, Kerslake, H, additional, Key, A L, additional, Khan, F, additional, Khunti, K, additional, Kilroy, S, additional, King, B, additional, King, C, additional, Kingham, L, additional, Kirk, J, additional, Kitterick, P, additional, Klenerman, P, additional, Knibbs, L, additional, Knight, S, additional, Knighton, A, additional, Kon, O, additional, Kon, S, additional, Kon, S S, additional, Korszun, A, additional, Koychev, I, additional, Kurasz, C, additional, Kurupati, P, additional, Laing, C, additional, Lamlum, H, additional, Landers, G, additional, Langenberg, C, additional, Lavelle-Langham, L, additional, Lawrie, A, additional, Lawson, C, additional, Layton, A, additional, Lea, A, additional, Leavy, O C, additional, Lee, J-H, additional, Lee, E, additional, Lee, D, additional, Leitch, K, additional, Lenagh, R, additional, Lewis, V, additional, Lewis, J, additional, Lewis, K E, additional, Lewis, D, additional, Lewis-Burke, N, additional, Li, X, additional, Light, T, additional, Lightstone, L, additional, Lilaonitkul, W, additional, Lim, L, additional, Linford, S, additional, Lingford-Hughes, A, additional, Lipman, M, additional, Liyanage, K, additional, Lloyd, A, additional, Logan, S, additional, Lomas, D, additional, Loosley, R, additional, Lota, H, additional, Lovegrove, W, additional, Lucey, A, additional, Lucy, L, additional, Lukaschuk, E, additional, Lye, A, additional, Lynch, C, additional, MacDonald, S, additional, MacGowan, G, additional, Macharia, I, additional, Mackie, J, additional, Macliver, L, additional, Madathil, S, additional, Madzamba, G, additional, Magee, N, additional, Magtoto, M M, additional, Mairs, N, additional, Majeed, N, additional, Major, E, additional, Malein, F, additional, Malim, M, additional, Mallison, G, additional, Man, W D-C, additional, Mandal, S, additional, Mangion, K, additional, Manisty, C, additional, Manley, R, additional, March, K, additional, Marciniak, S, additional, Marino, P, additional, Mariveles, M, additional, Marouzet, E, additional, Marsh, S, additional, Marshall, M, additional, Marshall, B, additional, Martin, J, additional, Martineau, A, additional, Martinez, L M, additional, Maskell, N, additional, Matila, D, additional, Matimba-Mupaya, W, additional, Matthews, L, additional, Mbuyisa, A, additional, McAdoo, S, additional, McAllister-Williams, H, additional, McArdle, P, additional, McArdle, A, additional, McAulay, D, additional, McCormick, W, additional, McCormick, J, additional, McCourt, P, additional, McCracken, C, additional, McGarvey, L, additional, McGee, C, additional, Mcgee, K, additional, McGinness, J, additional, McGlynn, K, additional, McGovern, A, additional, McGuinness, H, additional, McInnes, I B, additional, McIntosh, J, additional, McIvor, E, additional, McIvor, K, additional, McLeavey, L, additional, McMahon, A, additional, McMahon, M J, additional, McMorrow, L, additional, Mcnally, T, additional, McNarry, M, additional, McNeill, J, additional, McQueen, A, additional, McShane, H, additional, Mears, C, additional, Megson, C, additional, Megson, S, additional, Mehta, P, additional, Meiring, J, additional, Melling, L, additional, Mencias, M, additional, Menke, R, additional, Menzies, D, additional, Merida Morillas, M, additional, Michael, A, additional, Michael, B, additional, Miller, C A, additional, Milligan, L, additional, Mills, N L, additional, Mills, C, additional, Mills, G, additional, Milner, L, additional, Misra, S, additional, Mohamed, A, additional, Mohamed, N, additional, Mohammed, S, additional, Molyneaux, P L, additional, Monteiro, W, additional, Moriera, S, additional, Morley, A, additional, Morrison, L, additional, Morriss, R, additional, Morrow, A, additional, Moss, P, additional, Moss, A J, additional, Motohashi, K, additional, Msimanga, N, additional, Mukaetova-Ladinska, E, additional, Munawar, U, additional, Murira, J, additional, Nanda, U, additional, Nassa, H, additional, Nasseri, M, additional, Nathu, R, additional, Neal, A, additional, Needham, R, additional, Neill, P, additional, Neubauer, S, additional, Newby, D E, additional, Newell, H, additional, Newman, J, additional, Newman, T, additional, Newton-Cox, A, additional, Nichols, T E, additional, Nicholson, T, additional, Nicolaou, C, additional, Nicoll, D, additional, Nikolaidis, A, additional, Nikolaidou, C, additional, Nolan, C M, additional, Noonan, M J, additional, Norman, C, additional, Novotny, P, additional, Nunag, J L, additional, Nwafor, L, additional, Nwanguma, U, additional, Nyaboko, J, additional, O'Brien, C, additional, O'Donnell, K, additional, O'Regan, D P, additional, O'Brien, L, additional, Odell, N, additional, Ogbole, G, additional, Ogg, G, additional, Olaosebikan, O, additional, Oliver, C, additional, Omar, Z, additional, Openshaw, P J M, additional, Orriss-Dib, L, additional, Osborne, L, additional, Osbourne, R, additional, Ostermann, M, additional, Overton, C, additional, Owen, J, additional, Oxton, J, additional, Pack, J, additional, Pacpaco, E, additional, Paddick, S, additional, Painter, S, additional, Pakzad, A, additional, Palmer, S, additional, Papineni, P, additional, Paques, K, additional, Paradowski, K, additional, Pareek, M, additional, Parekh, D, additional, Parfrey, H, additional, Pariante, C, additional, Parker, S, additional, Parkes, M, additional, Parmar, J, additional, Patale, S, additional, Patel, M, additional, Patel, B, additional, Patel, S, additional, Pattenadk, D, additional, Pavlides, M, additional, Payne, S, additional, Pearce, L, additional, Pearl, J E, additional, Peckham, D, additional, Pendlebury, J, additional, Peng, Y, additional, Pennington, C, additional, Peralta, I, additional, Perkins, E, additional, Peterkin, Z, additional, Peto, T, additional, Petousi, N, additional, Petrie, J, additional, Pfeffer, P, additional, Phipps, J, additional, Piechnik, S, additional, Pimm, J, additional, Piper Hanley, K, additional, Pius, R, additional, Plant, H, additional, Plein, S, additional, Plowright, M, additional, Poinasamy, K, additional, Polgar, O, additional, Poll, L, additional, Porter, J, additional, Porter, J C, additional, Portukhay, S, additional, Powell, N, additional, Prabhu, A, additional, Pratt, J, additional, Price, A, additional, Price, C, additional, Price, L, additional, Price, D, additional, Prickett, A, additional, Propescu, I, additional, Propescu, J, additional, Prosper, S, additional, Pugmire, S, additional, Quaid, S, additional, Quigley, J, additional, Quint, J, additional, Qureshi, H, additional, Qureshi, I N, additional, Radhakrishnan, K, additional, Rahman, N M, additional, Ralser, M, additional, Ramos, H, additional, Ramos, A, additional, Rangeley, J, additional, Rangelov, B, additional, Ratcliffe, L, additional, Ravencroft, P, additional, Reddington, A, additional, Reddy, R, additional, Reddy, A, additional, Redfearn, H, additional, Redwood, D, additional, Reed, A, additional, Rees, M, additional, Rees, T, additional, Regan, K, additional, Reynolds, W, additional, Ribeiro, C, additional, Richards, A, additional, Richardson, E, additional, Richardson, M, additional, Rivera-Ortega, P, additional, Roberts, K, additional, Robertson, E, additional, Robinson, L, additional, Robinson, E, additional, Roche, L, additional, Roddis, C, additional, Rodger, J, additional, Rogers, N, additional, Ross, G, additional, Ross, A, additional, Rossdale, J, additional, Rostron, A, additional, Rowe, A, additional, Rowland, J, additional, Rowland, M J, additional, Rowland, A, additional, Rowland-Jones, S L, additional, Roy, M, additional, Roy, K, additional, Rudan, I, additional, Russell, R, additional, Russell, E, additional, Saalmink, G, additional, Sabit, R, additional, Sage, E K, additional, Samakomva, T, additional, Samani, N, additional, Samat, A A, additional, Sampson, C, additional, Samuel, K, additional, Samuel, R, additional, Sanders, Z B, additional, Sanderson, A, additional, Sapey, E, additional, Saralaya, D, additional, Sargant, J, additional, Sarginson, C, additional, Sass, T, additional, Sattar, N, additional, Saunders, K, additional, Saunders, P, additional, Saunders, L C, additional, Savill, H, additional, Saxon, W, additional, Sayer, A, additional, Schronce, J, additional, Schwaeble, W, additional, Scott, J T, additional, Scott, K, additional, Selby, N, additional, Sereno, M, additional, Sewell, T A, additional, Shah, K, additional, Shah, A, additional, Shah, P, additional, Shankar-Hari, M, additional, Sharma, M, additional, Sharpe, C, additional, Sharpe, M, additional, Shashaa, S, additional, Shaw, A, additional, Shaw, V, additional, Shaw, K, additional, Sheikh, A, additional, Shelton, S, additional, Shenton, L, additional, Shevket, K, additional, Shikotra, A, additional, Short, J, additional, Siddique, S, additional, Siddiqui, S, additional, Sidebottom, J, additional, Sigfrid, L, additional, Simons, G, additional, Simpson, N, additional, Simpson, J, additional, Singh, S, additional, Singh, C, additional, Singh, S J, additional, Sissons, D, additional, Skeemer, J, additional, Slack, K, additional, Smith, D, additional, Smith, A, additional, Smith, J, additional, Smith, L, additional, Smith, S, additional, Soares, M, additional, Solano, T S, additional, Solly, R, additional, Solstice, AR, additional, Soulsby, T, additional, Southern, D, additional, Sowter, D, additional, Spears, M, additional, Spencer, L G, additional, Speranza, F, additional, Stadon, L, additional, Stanel, S, additional, Steeds, R, additional, Steele, N, additional, Steiner, M, additional, Stensel, D, additional, Stephens, G, additional, Stephenson, L, additional, Stern, M, additional, Stewart, I, additional, Stimpson, R, additional, Stockdale, S, additional, Stockley, J, additional, Stoker, W, additional, Stone, R, additional, Storrar, W, additional, Storrie, A, additional, Storton, K, additional, Stringer, E, additional, Strong-Sheldrake, S, additional, Stroud, N, additional, Subbe, C, additional, Sudlow, C L, additional, Suleiman, Z, additional, Summers, C, additional, Summersgill, C, additional, Sutherland, D, additional, Sykes, D L, additional, Sykes, R, additional, Talbot, N, additional, Tan, A L, additional, Tarusan, L, additional, Tavoukjian, V, additional, Taylor, J, additional, Taylor, A, additional, Taylor, C, additional, Taylor, J P, additional, Te, A, additional, Tedd, H, additional, Tee, CJ, additional, Teixeira, J, additional, Tench, H, additional, Terry, S, additional, Thackray-Nocera, S, additional, Thaivalappil, F, additional, Thamu, B, additional, Thickett, D, additional, Thomas, D C, additional, Thomas, S, additional, Thomas, C, additional, Thomas, A K, additional, Thomas-Woods, T, additional, Thompson, A A R, additional, Thompson, T, additional, Thornton, T, additional, Thorpe, M, additional, Thwaites, R S, additional, Tilley, J, additional, Tinker, N, additional, Tiongson, G F, additional, Tobin, M, additional, Tomlinson, J, additional, Tong, C, additional, Toshner, M, additional, Touyz, R, additional, Treibel, T, additional, Tripp, K A, additional, Tunnicliffe, E M, additional, Turnbull, A, additional, Turner, K, additional, Turner, S, additional, Turner, V, additional, Turner, E, additional, Turney, S, additional, Turton, H, additional, Ugoji, J, additional, Ugwuoke, R, additional, Upthegrove, R, additional, Valabhji, J, additional, Ventura, M, additional, Vere, J, additional, Vickers, C, additional, Vinson, B, additional, Vogiatzis, I, additional, Wade, E, additional, Wade, P, additional, Wainwright, T, additional, Wajero, L O, additional, Walder, S, additional, Wall, E, additional, Wallis, T, additional, Walmsley, S, additional, Walsh, S, additional, Walsh, J A, additional, Warburton, L, additional, Ward, T J C, additional, Warwick, K, additional, Wassall, H, additional, Waterson, S, additional, Watson, L, additional, Watson, E, additional, Watson, J, additional, Webster, M, additional, Weir McCall, J, additional, Welch, H, additional, Welch, C, additional, Welsh, B, additional, Wessely, S, additional, West, S, additional, Weston, H, additional, Wheeler, H, additional, White, S, additional, Whitehead, V, additional, Whitney, J, additional, Whittaker, S, additional, Whittam, B, additional, Whitworth, V, additional, Wight, A, additional, Wild, J M, additional, Wilkins, M, additional, Wilkinson, D, additional, Williams, N, additional, Williams, B, additional, Williams, J, additional, Williams-Howard, S A, additional, Willicombe, M, additional, Willis, G, additional, Willoughby, J, additional, Wilson, A, additional, Wilson, I, additional, Wilson, D, additional, Window, N, additional, Witham, M, additional, Wolf-Roberts, R, additional, Wood, C, additional, Woodhead, F, additional, Woods, J, additional, Wootton, D G, additional, Wormleighton, J, additional, Worsley, J, additional, Wraith, D, additional, Wrey Brown, C, additional, Wright, C, additional, Wright, S, additional, Wright, L, additional, Wyles, J, additional, Wynter, I, additional, Xie, C, additional, Xu, M, additional, Yasmin, N, additional, Yasmin, S, additional, Yates, T, additional, Yip, K P, additional, Young, S, additional, Young, B, additional, Young, A, additional, Yousuf, A J, additional, Zawia, A, additional, Zeidan, L, additional, Zhao, B, additional, Zheng, B, additional, and Zongo, O, additional

Published
2023
Full Text
View/download PDF

28. Association between segmental noninvasive longitudinal strain and quantitative microvascular perfusion in ST-segment elevation myocardial infarction: implications for clinical outcomes

Author

Rui Zhang, Shuxin Liang, Fan Zhao, Bang Du, Ruo-Nan Wang, Wen-Jia Shi, and Ai-Ai Chu

Subjects
Longitudinal strain, Quantitative microvascular perfusion, Myocardial infarction, Diseases of the circulatory (Cardiovascular) system, RC666-701
Abstract

Abstract Objective This study aims to investigate the relationship between segmental longitudinal strain (LS) and quantitative microvascular perfusion (qMVP) in patients with ST-segment elevation myocardial infarction (STEMI), and to explore the prognostic value of the two indicators after STEMI. Methods The retrospective study enrolled 61 patients who underwent primary percutaneous coronary intervention (pPCI) for first STEMI. Microvascular perfusion (MVP) and qMVP were analyzed by myocardial contrast echocardiography (MCE), and segmental LS was analyzed by two-dimensional speckle tracking echocardiography (2D-STE). Myocardial wall perfusion was qualitatively assessed visually. Quantitative myocardial perfusion parameters were analyzed using an 18-segment model. The correlation between segmental LS and qMVP was assessed. The prognostic value of segmental LS and qMVP for major cardiac adverse events were evaluated. Results Among the 314 segments with abnormal wall motion, 44 showed normal microvascular perfusion (nMVP), 87 showed delayed microvascular perfusion (dMVP), and 183 exhibited microvascular obstruction (MVO). Segmental LS was correlated with segmental wall motion (WM) and qMVP. At 12-month follow-up, 19 patients experienced cardiac events. NT-proBNP, regional LS (rLS), and regional qMVP (r-qMVP) were associated with cardiac events. The area under curve (AUC) of combination of rLS and r-qMVP was bigger than single indicator for identifying prognostic value (P

Published
2025
Full Text
View/download PDF

29. Constraining a Model of the Radio Sky Below 6 MHz Using the Parker Solar Probe/FIELDS Instrument in Preparation for Upcoming Lunar-based Experiments

Author

Bassett, Neil, Rapetti, David, Nhan, Bang D., Page, Brent, Burns, Jack O., Pulupa, Marc, Bale, Stuart D., Bassett, Neil, Rapetti, David, Nhan, Bang D., Page, Brent, Burns, Jack O., Pulupa, Marc, and Bale, Stuart D.

Abstract

We present a Bayesian analysis of data from the FIELDS instrument on board the Parker Solar Probe (PSP) spacecraft with the aim of constraining low frequency ($\lesssim$ 6 MHz) sky in preparation for several upcoming lunar-based experiments. We utilize data recorded during PSP's ``coning roll'' maneuvers, in which the axis of the spacecraft is pointed 45$^{\circ}$ off of the Sun. The spacecraft then rotates about a line between the Sun and the spacecraft with a period of 24 minutes. We reduce the data into two formats: roll-averaged, in which the spectra are averaged over the roll, and phase-binned, in which the spectra are binned according to the phase of the roll. We construct a forward model of the FIELDS observations that includes numerical simulations of the antenna beam, an analytic emissivity function of the galaxy, and estimates of the absorption due to free electrons. Fitting 5 parameters, we find that the roll-averaged data can be fit well by this model and we obtain posterior parameter constraints that are in general agreement with previous estimates. The model is not, however, able to fit the phase-binned data well, likely due to limitations such as the lack of non-smooth emission structure at both small and large scales, enforced symmetry between the northern and southern galactic hemispheres, and large uncertainties in the free electron density. This suggests that significant improvement in the low frequency sky model is needed in order to fully and accurately represent the sky at frequencies below 6 MHz., Comment: 18 pages, 10 figures, 5 tables. Under review in the Astrophysical Journal

Published
2023
Full Text
View/download PDF

36. 381P A tumor-informed, hybrid-capture based ctDNA assay for minimal residual disease (MRD) detection in colorectal cancer (CRC) patients after curative surgery

Author

Han, S-W., primary, Heo, S., additional, Lim, Y., additional, Lee, W., additional, Kim, H-P., additional, Kim, S.Y., additional, Bang, D., additional, Park, K.J., additional, Oh, S.T., additional, Yoo, C.S., additional, Kang, S-B., additional, Kim, Y-J., additional, and Kim, T-Y., additional

Published
2022
Full Text
View/download PDF

40. CRS

Author

Vo, Nhi N. Y., primary, Vu, Nam H., additional, Vu, Tu A., additional, Vu, Quang T., additional, and Mach, Bang D., additional

Published
2022
Full Text
View/download PDF

44. Joint metabolomics and transcriptomics analysis systematically reveal the impact of MYCN in neuroblastoma

Author

Bang Du, Yingyu Zhang, Pin Zhang, Mengxin Zhang, Zhidan Yu, Lifeng Li, Ligong Hou, Qionglin Wang, Xianwei Zhang, and Wancun Zhang

Subjects
MYCN amplification, Neuroblastoma, Metabolomics, Transcriptomics, Therapeutic target, Molecular mechanism, Medicine, Science
Abstract

Abstract The limited understanding of the molecular mechanism underlying MYCN-amplified (MNA) neuroblastoma (NB) has hindered the identification of effective therapeutic targets for MNA NB, contributing to its higher mortality rate compared to MYCN non-amplified (non-MNA) NB. Therefore, a comprehensive analysis integrating metabolomics and transcriptomics was conducted to systematically investigate the MNA NB. Metabolomics analysis utilized plasma samples from 28 MNA NB patients and 68 non-MNA NB patients, while transcriptomics analysis employed tissue samples from 15 MNA NB patients and 37 non-MNA NB patients. Notably, joint metabolomics and transcriptomics analysis was performed. A total of 46 metabolites exhibited alterations, with 21 displaying elevated levels and 25 demonstrating reduced levels in MNA NB. In addition, 884 mRNAs in MNA NB showed significant changes, among which 766 mRNAs were higher and 118 mRNAs were lower. Joint-pathway analysis revealed three aberrant pathways involving glycerolipid metabolism, purine metabolism, and lysine degradation. This study highlights the substantial differences in metabolomics and transcriptomics between MNA NB and non-MNA NB, identifying three abnormal metabolic pathways that may serve as potential targets for understanding the molecular mechanisms underlying MNA NB.

Published
2024
Full Text
View/download PDF

45. Biliary atresia and cholestasis plasma non-targeted metabolomics unravels perturbed metabolic pathways and unveils a diagnostic model for biliary atresia

Author

Bang Du, Kai Mu, Meng Sun, Zhidan Yu, Lifeng Li, Ligong Hou, Qionglin Wang, Jushan Sun, Jinhua Chen, Xianwei Zhang, and Wancun Zhang

Subjects
Metabolomics, Biliary atresia, Cholestasis, Blood plasma, Diagnostic model, Medicine, Science
Abstract

Abstract The clinical diagnosis of biliary atresia (BA) poses challenges, particularly in distinguishing it from cholestasis (CS). Moreover, the prognosis for BA is unfavorable and there is a dearth of effective non-invasive diagnostic models for detection. Therefore, the aim of this study is to elucidate the metabolic disparities among children with BA, CS, and normal controls (NC) without any hepatic abnormalities through comprehensive metabolomics analysis. Additionally, our objective is to develop an advanced diagnostic model that enables identification of BA. The plasma samples from 90 children with BA, 48 children with CS, and 47 NC without any liver abnormalities children were subjected to metabolomics analysis, revealing significant differences in metabolite profiles among the 3 groups, particularly between BA and CS. A total of 238 differential metabolites were identified in the positive mode, while 89 differential metabolites were detected in the negative mode. Enrichment analysis revealed 10 distinct metabolic pathways that differed, such as lysine degradation, bile acid biosynthesis. A total of 18 biomarkers were identified through biomarker analysis, and in combination with the exploration of 3 additional biomarkers (LysoPC(18:2(9Z,12Z)), PC (22:5(7Z,10Z,13Z,16Z,19Z)/14:0), and Biliverdin-IX-α), a diagnostic model for BA was constructed using logistic regression analysis. The resulting ROC area under the curve was determined to be 0.968. This study presents an innovative and pioneering approach that utilizes metabolomics analysis to develop a diagnostic model for BA, thereby reducing the need for unnecessary invasive examinations and contributing to advancements in diagnosis and prognosis for patients with BA.

Published
2024
Full Text
View/download PDF

47. Intensified Antituberculosis Therapy in Adults with Tuberculous Meningitis

Author

Heemskerk, Dorothee A., Nguyen, Bang D., Nguyen, Mai T.H., Tran, Chau T.H., Nguyen, Phu H., Pham, Loc P., Nguyen, Chau V.V., Tran, Hien T., Nguyen, Dung H., Nguyen, Lan T.N., Nguyen, Lan H., Nguyen, Lan N., Le, Phong T., Nguyen, Vien N., Nguyen, Hien Q., Nguyen, Yen T.B., Dang, Ha T.M., Day, Jeremy N., Caws, Maxine, Merson, Laura, Tran, Thinh T.V., Wolbers, Marcel, Thwaites, Guy E., and Farrar, Jeremy J.

Published
2016
Full Text
View/download PDF

48. The Precision Radio Instrument for Antenna Measurements (PRIAM): measurement strategy

Author

Varundev Sukhil, Bang D. Nhan, Richard F. Bradley, Krishna Makhija, and Joanne Bechta Dugan

Subjects
Physics, business.industry, Orders of magnitude (temperature), Astrophysics::High Energy Astrophysical Phenomena, Instrumentation, Astrophysics::Instrumentation and Methods for Astrophysics, Measure (physics), Astrophysics::Cosmology and Extragalactic Astrophysics, Optics, Modulation, Line (geometry), Antenna (radio), business, Astrophysics::Galaxy Astrophysics, Beam (structure), Voltage
Abstract

The emergence of experimental 21-cm cosmology engenders unique challenges towards its instrumentation. The presence of bright foregrounds consisting of Galactic and extragalactic synchrotron emission several orders of magnitude higher than the expected highly- redshifted 21-cm line places high precision requirements on the antenna beam. We present an antenna calibration technique that utilizes a drone with high precision positioning and unique modulation techniques to measure the complex voltage beam of an antenna-under-test (AUT) to the required degree of precision.

Published
2021
Full Text
View/download PDF

49. Not on the same wavelength? How autistic traits influence cooperation: evidence from fNIRS hyperscanning

Author

Kaiyun Li, Bang Du, Xue Guan, Liu Chen, Mingxue Wang, Gongxiang Chen, Fanlu Jia, and Xiaoqing Jiang

Subjects
autistic traits, cooperation, empathy, interpersonal brain synchronization, fNIRS, Psychiatry, RC435-571
Abstract

BackgroundIndividuals with high autistic traits exhibit characteristics like those of individuals with autism, including impairments in sociability and communication skills. Whether individuals with high autistic traits exhibit less cooperation remains debated.MethodsThis study employed the prisoner’s dilemma game (PDG) to measure cooperation in 56 dyads, including 27 with high-low (HL) autistic traits and 29 with low-low (LL) autistic traits, using functional near-infrared spectroscopy (fNIRS) hyperscanning technique. Cognitive and emotional empathy were also measured.ResultsIndividuals with high autistic traits had a lower unilateral cooperation rate than did those with low autistic traits; The HL autistic dyads exhibited a lower mutual cooperation rate and reduced interpersonal brain synchronization (IBS) in the right inferior parietal lobule (r-IPL) and right temporoparietal junction (r-TPJ) compared with the LL autistic dyads; Individuals with high autistic traits had significantly lower cognitive empathy scores than did those with low autistic traits, and the cognitive empathy scores had a marginally significant positive correlation with the unilateral cooperation rate and a marginally significant negative correlation with the activation of the right inferior frontal gyrus (r-IFG); Emotional empathy scores did not significantly differ between the high and low autistic groups, and there was a significant positive correlation between emotional empathy scores and the activation of the r-IFG in individuals with high autistic traits.ConclusionThis study revealed abnormal cooperation in individuals with high autistic traits from unilateral and mutual behavior neural perspectives, potentially linked to a disability of cognitive empathy.

Published
2024
Full Text
View/download PDF

50. First detection of fungal diversity associated with Prunus salicina Lindl malformation syndrome

Author

Dan Huang, Po Pu, Xiaosi He, Mingxian Lan, Bang Du, Lixia Zhu, Qian Li, Yongli Yang, Rui Xiang, Longzhang Wang, Guizhen Li, and Rongjiao Wang

Subjects
prunus salicina lindl, malformation, its, fungal diversity, Biotechnology, TP248.13-248.65, Life, QH501-531
Abstract

The Chinese deciduous fruit Prunus salicina Lindl is loved by people because of its distinctive flavor and significant industrial worth. This study presents the first report of abnormal leaf bud in Prunus salicina Lindl. Malformation of Prunus salicina Lindl leaf buds leads to abnormal development and growth, causing deformities and a decrease in fruit yield. Identifying the underlying causes and causative pathogens is essential for effective disease management. In this experiment, we observed the Malformation Syndrome in Prunus salicina Lindl and used the internal transcribed spacer (ITS) to compare fungal diversity between malformed and healthy leaf buds. These results show a higher level of fungal diversity in diseased leaf buds. Alternaria, Curvibasidium, Symmetrospora, Fonsecazyma, and other genera among the identified fungi are suspected to induce the malformations. Potential contributors to these malformations include Endophyte-plant_Pathogen and Plant_pathogen-Undefined_saprotroph. These findings provide valuable insights for further research on the etiology of plum bud diseases, identifying potential pathogens, and formulating control strategies.

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results