18,698 results on '"Kaplan, David"'
Search Results
152. Groundwater impacts of adding carrot to corn-peanut rotations in North Florida
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Lee, Dogil, Merrick, Jason, Rath, Sagarika, Dukes, Michael, Kaplan, David, and Graham, Wendy
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- 2024
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153. Liver Stiffness Measurement and Risk Prediction of Hepatocellular Carcinoma After HCV Eradication in Veterans With Cirrhosis
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John, Binu V., Dang, Yangyang, Kaplan, David E., Jou, Janice H., Taddei, Tamar H., Spector, Seth A., Martin, Paul, Bastaich, Dustin R., Chao, Hann-Hsiang, and Dahman, Bassam
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- 2024
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154. Silk fibroin, gelatin, and human placenta extracellular matrix-based composite hydrogels for 3D bioprinting and soft tissue engineering
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Schneider, Karl Heinrich, Goldberg, Benjamin J., Hasturk, Onur, Mu, Xuan, Dötzlhofer, Marvin, Eder, Gabriela, Theodossiou, Sophia, Pichelkastner, Luis, Riess, Peter, Rohringer, Sabrina, Kiss, Herbert, Teuschl-Woller, Andreas H., Fitzpatrick, Vincent, Enayati, Marjan, Podesser, Bruno K., Bergmeister, Helga, and Kaplan, David L.
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- 2023
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155. Concurrent application of interferon-gamma and vincristine inhibits tumor growth in an orthotopic neuroblastoma mouse model
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Zeki, Jasmine, Yavuz, Burcin, Wood, Lauren, Shimada, Hiroyuki, Kaplan, David L., and Chiu, Bill
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- 2023
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156. Continuous fish muscle cell line with capacity for myogenic and adipogenic-like phenotypes
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Saad, Michael K., Yuen, Jr, John S. K., Joyce, Connor M., Li, Xinxin, Lim, Taehwan, Wolfson, Talia L., Wu, Justin, Laird, Jason, Vissapragada, Sanjana, Calkins, Olivia P., Ali, Adham, and Kaplan, David L.
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- 2023
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157. Bayesian historical borrowing with longitudinal large-scale assessments
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Kaplan, David, Chen, Jianshen, Lyu, Weicong, and Yavuz, Sinan
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- 2023
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158. Volumetric additive manufacturing of pristine silk-based (bio)inks
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Xie, Maobin, Lian, Liming, Mu, Xuan, Luo, Zeyu, Garciamendez-Mijares, Carlos Ezio, Zhang, Zhenrui, López, Arturo, Manríquez, Jennifer, Kuang, Xiao, Wu, Junqi, Sahoo, Jugal Kishore, González, Federico Zertuche, Li, Gang, Tang, Guosheng, Maharjan, Sushila, Guo, Jie, Kaplan, David L., and Zhang, Yu Shrike
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- 2023
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159. Trade-offs between bycatch and target catches in static versus dynamic fishery closures.
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Pons, Maite, Watson, Jordan, Ovando, Daniel, Andraka, Sandra, Brodie, Stephanie, Domingo, Andrés, Fitchett, Mark, Forselledo, Rodrigo, Hall, Martin, Hazen, Elliott, Jannot, Jason, Herrera, Miguel, Jiménez, Sebastián, Kaplan, David, Kerwath, Sven, Lopez, Jon, McVeigh, Jon, Pacheco, Lucas, Rendon, Liliana, Richerson, Kate, SantAna, Rodrigo, Sharma, Rishi, Smith, James, Somers, Kayleigh, and Hilborn, Ray
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bycatch mitigation ,fisheries management ,marine protected areas ,static and dynamic closures ,Conservation of Natural Resources ,Ecosystem ,Fisheries ,Oceanography - Abstract
While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evaluated evidence for the effects of temporal, static, and dynamic area closures on the bycatch and target catch of 15 fisheries around the world. Assuming perfect knowledge of where the catch and bycatch occurs and a closure of 30% of the fishing area, we found that dynamic area closures could reduce bycatch by an average of 57% without sacrificing catch of target species, compared to 16% reductions in bycatch achievable by static closures. The degree of bycatch reduction achievable for a certain quantity of target catch was related to the correlation in space and time between target and bycatch species. If the correlation was high, it was harder to find an area to reduce bycatch without sacrificing catch of target species. If the goal of spatial closures is to reduce bycatch, our results suggest that dynamic management provides substantially better outcomes than classic static marine area closures. The use of dynamic ocean management might be difficult to implement and enforce in many regions. Nevertheless, dynamic approaches will be increasingly valuable as climate change drives species and fisheries into new habitats or extended ranges, altering species-fishery interactions and underscoring the need for more responsive and flexible regulatory mechanisms.
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- 2022
160. Variations of Nationalism
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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161. How Do Nationalism and Geography Interact?
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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162. Multinational, Federalist, and Supranationalist States
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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163. Territory, Networks, and Place
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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164. Nationalism at the Local Scale
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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165. Ethno-Regionalist and Ethno-Nationalist Movements
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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166. Action, Performance, and Agency
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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167. Mapping and Symbols of Nationhood
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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168. Growth of an Ideology
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Kaplan, David H., primary and Hannum, Kathryn, additional
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- 2023
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169. Photoacoustic Silk Scaffolds for Neural stimulation and Regeneration
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Zheng, Nan, Fitzpatrick, Vincent, Cheng, Ran, Shi, Linli, Kaplan, David L., and Yang, Chen
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Quantitative Biology - Neurons and Cognition ,Quantitative Biology - Tissues and Organs - Abstract
Neural interfaces using biocompatible scaffolds provide crucial properties for the functional repair of nerve injuries and neurodegenerative diseases, including cell adhesion, structural support, and mass transport. Neural stimulation has also been found to be effective in promoting neural regeneration. This work provides a new strategy to integrate photoacoustic (PA) neural stimulation into hydrogel scaffolds using a nanocomposite hydrogel approach. Specifically, polyethylene glycol (PEG)-functionalized carbon nanotubes (CNT), highly efficient photoacoustic agents, are embedded into silk fibroin to form biocompatible and soft photoacoustic materials. We show that these photoacoustic functional scaffolds enable non-genetic activation of neurons with a spatial precision defined by the area of light illumination, promoting neuron regeneration. These CNT/silk scaffolds offered reliable and repeatable photoacoustic neural stimulation. 94% of photoacoustic stimulated neurons exhibit a fluorescence change larger than 10% in calcium imaging in the light illuminated area. The on-demand photoacoustic stimulation increased neurite outgrowth by 1.74-fold in a dorsal root ganglion model, when compared to the unstimulated group. We also confirmed that photoacoustic neural stimulation promoted neurite outgrowth by impacting the brain-derived neurotrophic factor (BDNF) pathway. As a multifunctional neural scaffold, CNT/silk scaffolds demonstrated non-genetic PA neural stimulation functions and promoted neurite outgrowth, providing a new method for non-pharmacological neural regeneration.
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- 2021
170. A Causal Framework for Non-Linear Quantum Mechanics
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Kaplan, David E. and Rajendran, Surjeet
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High Energy Physics - Theory ,General Relativity and Quantum Cosmology ,High Energy Physics - Phenomenology ,Quantum Physics - Abstract
We add non-linear and state-dependent terms to quantum field theory. We show that the resulting low-energy theory, non-linear quantum mechanics, is causal, preserves probability and permits a consistent description of the process of measurement. We explore the consequences of such terms and show that non-linear quantum effects can be observed in macroscopic systems even in the presence of de-coherence. We find that current experimental bounds on these non-linearities are weak and propose several experimental methods to significantly probe these effects. The locally exploitable effects of these non-linearities have enormous technological implications. For example, they would allow large scale parallelization of computing (in fact, any other effort) and enable quantum sensing beyond the standard quantum limit. We also expose a fundamental vulnerability of any non-linear modification of quantum mechanics - these modifications are highly sensitive to cosmic history and their locally exploitable effects can dynamically disappear if the observed universe has a tiny overlap with the overall quantum state of the universe, as is predicted in conventional inflationary cosmology. We identify observables that persist in this case and discuss opportunities to detect them in cosmic ray experiments, tests of strong field general relativity and current probes of the equation of state of the universe. Non-linear quantum mechanics also enables novel gravitational phenomena and may open new directions to solve the black hole information problem and uncover the theory underlying quantum field theory and gravitation., Comment: 22 pages, 0 figures, Journal Version
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- 2021
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171. Radio Afterglows from Compact Binary Coalescences: Prospects for Next-Generation Telescopes
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Dobie, Dougal, Murphy, Tara, Kaplan, David L., Hotokezaka, Kenta, Ataides, Juan Pablo Bonilla, Mahony, Elizabeth K., and Sadler, Elaine M.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
The detection of gravitational waves from a neutron star merger, GW170817, marked the dawn of a new era in time-domain astronomy. Monitoring of the radio emission produced by the merger, including high-resolution radio imaging, enabled measurements of merger properties including the energetics and inclination angle. In this work we compare the capabilities of current and future gravitational wave facilities to the sensitivity of radio facilities to quantify the prospects for detecting the radio afterglows of gravitational wave events. We consider three observing strategies to identify future mergers -- widefield follow-up, targeting galaxies within the merger localisation and deep monitoring of known counterparts. We find that while planned radio facilities like the Square Kilometre Array will be capable of detecting mergers at gigaparsec distances, no facilities are sufficiently sensitive to detect mergers at the range of proposed third-generation gravitational wave detectors that would operate starting in the 2030s.
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- 2021
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172. A Search for Extragalactic Fast Blue Optical Transients in ZTF and the Rate of AT2018cow-like Transients
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Ho, Anna Y. Q., Perley, Daniel A., Gal-Yam, Avishay, Lunnan, Ragnhild, Sollerman, Jesper, Schulze, Steve, Das, Kaustav K., Dobie, Dougal, Yao, Yuhan, Fremling, Christoffer, Adams, Scott, Anand, Shreya, Andreoni, Igor, Bellm, Eric C., Bruch, Rachel J., Burdge, Kevin B., Castro-Tirado, Alberto J., Dahiwale, Aishwarya, De, Kishalay, Dekany, Richard, Drake, Andrew J., Duev, Dmitry A., Graham, Matthew J., Helou, George, Kaplan, David L., Karambelkar, Viraj, Kasliwal, Mansi M., Kool, Erik C., Kulkarni, S. R., Mahabal, Ashish A., Medford, Michael S., Miller, A. A., Nordin, Jakob, Ofek, Eran, Petitpas, Glen, Riddle, Reed, Sharma, Yashvi, Smith, Roger, Stewart, Adam J., Taggart, Kirsty, Tartaglia, Leonardo, Tzanidakis, Anastasios, and Winters, Jan Martin
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a search for extragalactic fast blue optical transients (FBOTs) during Phase I of the Zwicky Transient Facility (ZTF). We identify 38 candidates with durations above half-maximum light 1 d < t1/2 < 12 d, of which 28 have blue (g-r<-0.2 mag) colors at peak light. Of the 38 transients (28 FBOTs), 19 (13) can be spectroscopically classified as core-collapse supernovae (SNe): 11 (8) H- or He-rich (Type II/IIb/Ib) SNe, 6 (4) interacting (Type IIn/Ibn) SNe, and 2 (1) H&He-poor (Type Ic/Ic-BL) SNe. Two FBOTs (published previously) had high-S/N predominantly featureless spectra and luminous radio emission: AT2018lug and AT2020xnd. Seven (five) did not have a definitive classification: AT 2020bdh showed tentative broad H$\alpha$ in emission, and AT 2020bot showed unidentified broad features and was 10 kpc offset from the center of an early-type galaxy. Ten (six) have no spectroscopic observations or redshift measurements. We present multiwavelength (radio, millimeter, and/or X-ray) observations for five FBOTs (three Type Ibn, one Type IIn/Ibn, one Type IIb). Additionally, we search radio-survey (VLA and ASKAP) data to set limits on the presence of radio emission for 22 of the transients. All X-ray and radio observations resulted in non-detections; we rule out AT2018cow-like X-ray and radio behavior for five FBOTs and more luminous emission (such as that seen in the Camel) for four additional FBOTs. We conclude that exotic transients similar to AT2018cow, the Koala, and the Camel represent a rare subset of FBOTs, and use ZTF's SN classification experiments to measure the rate to be at most 0.1% of the local core-collapse SN rate., Comment: Replaced following peer-review process. 46 pages, 20 figures. Accepted for publication in ApJ
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- 2021
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173. Searching For Gravitational Waves From Cosmological Phase Transitions With The NANOGrav 12.5-year dataset
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Arzoumanian, Zaven, Baker, Paul T., Blumer, Harsha, Bécsy, Bence, Brazier, Adam, Brook, Paul R., Burke-Spolaor, Sarah, Charisi, Maria, Chatterjee, Shami, Chen, Siyuan, Cordes, James M., Cornish, Neil J., Crawford, Fronefield, Cromartie, H. Thankful, DeCesar, Megan E., Demorest, Paul B., Dolch, Timothy, Ellis, Justin A., Ferrara, Elizabeth C., Fiore, William, Fonseca, Emmanuel, Garver-Daniels, Nathan, Gentile, Peter A., Good, Deborah C., Hazboun, Jeffrey S., Holgado, A. Miguel, Islo, Kristina, Jennings, Ross J., Jones, Megan L., Kaiser, Andrew R., Kaplan, David L., Kelley, Luke Zoltan, Key, Joey Shapiro, Laal, Nima, Lam, Michael T., Lazio, T. Joseph W., Lee, Vincent S. H., Lorimer, Duncan R., Luo, Jing, Lynch, Ryan S., Madison, Dustin R., McLaughlin, Maura A., Mingarelli, Chiara M. F., Mitridate, Andrea, Ng, Cherry, Nice, David J., Pennucci, Timothy T., Pol, Nihan S., Ransom, Scott M., Ray, Paul S., Shapiro-Albert, Brent J., Siemens, Xavier, Simon, Joseph, Spiewak, Renée, Stairs, Ingrid H., Stinebring, Daniel R., Stovall, Kevin, Sun, Jerry P., Swiggum, Joseph K., Taylor, Stephen R., Turner, Jacob E., Vallisneri, Michele, Vigeland, Sarah J., Witt, Caitlin A., and Zurek, Kathryn M.
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Astrophysics - Cosmology and Nongalactic Astrophysics ,High Energy Physics - Phenomenology - Abstract
We search for a first-order phase transition gravitational wave signal in 45 pulsars from the NANOGrav 12.5 year dataset. We find that the data can be modeled in terms of a strong first order phase transition taking place at temperatures below the electroweak scale. However, we do not observe any strong preference for a phase-transition interpretation of the signal over the standard astrophysical interpretation in terms of supermassive black holes mergers; but we expect to gain additional discriminating power with future datasets, improving the signal to noise ratio and extending the sensitivity window to lower frequencies. An interesting open question is how well gravitational wave observatories could separate such signals., Comment: 13 pages, 4 figures. v2: updated to match published version
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- 2021
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174. Fast-transient Searches in Real Time with ZTFReST: Identification of Three Optically-discovered Gamma-ray Burst Afterglows and New Constraints on the Kilonova Rate
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Andreoni, Igor, Coughlin, Michael W., Kool, Erik C., Kasliwal, Mansi M., Kumar, Harsh, Bhalerao, Varun, Carracedo, Ana Sagués, Ho, Anna Y. Q., Pang, Peter T. H., Saraogi, Divita, Sharma, Kritti, Shenoy, Vedant, Burns, Eric, Ahumada, Tomás, Anand, Shreya, Singer, Leo P., Perley, Daniel A., De, Kishalay, Fremling, U. C., Bellm, Eric C., Bulla, Mattia, Crellin-Quick, Arien, Dietrich, Tim, Drake, Andrew, Duev, Dmitry A., Goobar, Ariel, Graham, Matthew J., Kaplan, David L., Kulkarni, S. R., Laher, Russ R., Mahabal, Ashish A., Shupe, David L., Sollerman, Jesper, Walters, Richard, and Yao, Yuhan
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
While optical surveys regularly discover slow transients like supernovae on their own, the most common way to discover extragalactic fast transients, fading away in a few nights, is via follow-up observations of gamma-ray burst and gravitational-wave triggers. However, wide-field surveys have the potential to also identify rapidly fading transients independently of such external triggers. The volumetric survey speed of the Zwicky Transient Facility (ZTF) makes it sensitive to faint and fast-fading objects as kilonovae, the optical counterparts to binary neutron stars and neutron star-black hole mergers, out to almost 200Mpc. We introduce an open-source software infrastructure, the ZTF REaltime Search and Triggering, ZTFReST, designed to identify kilonovae and fast optical transients in ZTF data. Using the ZTF alert stream combined with forced photometry, we have implemented automated candidate ranking based on their photometric evolution and fitting to kilonova models. Automated triggering of follow-up systems, such as Las Cumbres Observatory, has also been implemented. In 13 months of science validation, we found several extragalactic fast transients independent of any external trigger (though some counterparts were identified later), including at least one supernova with post-shock cooling emission, two known afterglows with an associated gamma-ray burst, two known afterglows without any known gamma-ray counterpart, and three new fast-declining sources (ZTF20abtxwfx, ZTF20acozryr, and ZTF21aagwbjr) that are likely associated with GRB200817A, GRB201103B, and GRB210204A. However, we have not found any objects which appear to be kilonovae; therefore, we constrain the rate of GW170817-like kilonovae to $R < 900$Gpc$^{-3}$yr$^{-1}$. A framework such as ZTFReST could become a prime tool for kilonova and fast transient discovery with the Vera C. Rubin Observatory., Comment: Submitted for publication
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- 2021
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175. Silk chemistry and biomedical material designs
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Sahoo, Jugal Kishore, Hasturk, Onur, Falcucci, Thomas, and Kaplan, David L.
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- 2023
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176. Functional bioengineered models of the central nervous system
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Rouleau, Nicolas, Murugan, Nirosha J., and Kaplan, David L.
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- 2023
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177. Type of Infection Is Associated with Prognosis in Acute-on-Chronic Liver Failure: A National Veterans Health Administration Study
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Mahmud, Nadim, Reddy, K. Rajender, Taddei, Tamar H., and Kaplan, David E.
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- 2023
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178. Construct validity evidence reporting practices for the Reading the Mind in the Eyes Test: A systematic scoping review
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Higgins, Wendy C., Kaplan, David M., Deschrijver, Eliane, and Ross, Robert M.
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- 2024
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179. Rates, patterns, and predictors of specialty palliative care consultation among patients with acute-on-chronic liver failure
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Patel, Arpan, Walling, Anne, Kanwal, Fasiha, Serper, Marina, Hernaez, Ruben, Sundaram, Vinay, Kaplan, David, Taddei, Tamar, and Mahmud, Nadim
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- 2024
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180. Preoperative Hepatology and Primary Care Visits Improve Postoperative Outcomes in Patients with Cirrhosis Undergoing Surgery
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Ghandour, Bachir, Tapper, Elliot B., Kaplan, David E., Serper, Marina, and Mahmud, Nadim
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- 2024
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181. A missense variant in human perilipin 2 (PLIN2 Ser251Pro) reduces hepatic steatosis in mice
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Scorletti, Eleonora, Saiman, Yedidya, Jeon, Sookyoung, Schneider, Carolin V., Buyco, Delfin G., Lin, Chelsea, Himes, Blanca E., Mesaros, Clementina A., Vujkovic, Marijana, Creasy, Kate Townsend, Furth, Emma E., Billheimer, Jeffrey T., Hand, Nicholas J., Kaplan, David E., Chang, Kyong-Mi, Tsao, Philip S., Lynch, Julie A., Dempsey, Joseph L., Harkin, Julia, Bayen, Susovon, Conlon, Donna, Guerraty, Marie, Phillips, Michael C., Rader, Daniel J., and Carr, Rotonya M.
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- 2024
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182. Continued radio observations of GW170817 3.5 years post-merger
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Balasubramanian, Arvind, Corsi, Alessandra, Mooley, Kunal P., Brightman, Murray, Hallinan, Gregg, Hotokezaka, Kenta, Kaplan, David L., Lazzati, Davide, and Murphy, Eric J.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present new radio observations of the binary neutron star merger GW170817 carried out with the Karl G. Jansky Very large Array (VLA) more than 3\,yrs after the merger. Our combined dataset is derived by co-adding more than $\approx32$\,hours of VLA time on-source, and as such provides the deepest combined observation (rms sensitivity $\approx 0.99\,\mu$Jy) of the GW170817 field obtained to date at 3\,GHz. We find no evidence for a late-time radio re-brightening at a mean epoch of $t\approx 1200$\,d since merger, in contrast to a $\approx 2.1\,\sigma$ excess observed at X-ray wavelengths at the same mean epoch. Our measurements agree with expectations from the post-peak decay of the radio afterglow of the GW170817 structured jet. Using these results, we constrain the parameter space of models that predict a late-time radio re-brightening possibly arising from the high-velocity tail of the GW170817 kilonova ejecta, which would dominate the radio and X-ray emission years after the merger (once the structured jet afterglow fades below detection level). Our results point to a steep energy-speed distribution of the kilonova ejecta (with energy-velocity power law index $\alpha \gtrsim 5$). We suggest possible implications of our radio analysis, when combined with the recent tentative evidence for a late-time re-brightening in the X-rays, and highlight the need for continued radio-to-X-ray monitoring to test different scenarios., Comment: 6 pages, 2 figures. Version published in ApJL (includes minor updates to figures, data and refs)
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- 2021
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183. Gravitational contributions to the electron $g$-factor
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Cohen, Andrew G. and Kaplan, David B.
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High Energy Physics - Phenomenology ,General Relativity and Quantum Cosmology ,High Energy Physics - Experiment ,High Energy Physics - Theory ,Physics - Atomic Physics - Abstract
In a previous paper, the authors with Ann Nelson proposed that the UV and IR applicability of effective quantum field theories should be constrained by requiring that strong gravitational effects are nowhere encountered in a theory's domain of validity [Phys. Rev. Lett. 82, 4971 (1999)]. The constraint was proposed to delineate the boundary beyond which conventional quantum field theory, viewed as an effective theory excluding quantum gravitational effects, might be expected to break down. In this Letter we revisit this idea and show that quantum gravitational effects could lead to a deviation of size $(\alpha/2\pi)\sqrt{m_e/M_p}$ from the Standard Model calculation for the electron magnetic moment. This is the same size as QED and hadronic uncertainties in the theory of $a_e$, and a little more than one order of magnitude smaller than both the dominant uncertainty in its Standard Model value arising from the accuracy with which $\alpha$ is measured, as well as the experimental uncertainty in measurement of $a_e$., Comment: 3 pages
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- 2021
184. Constraints on Relic Magnetic Black Holes
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Diamond, Melissa D. and Kaplan, David E.
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High Energy Physics - Phenomenology ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present current direct and astrophysical limits on the cosmological abundance of black holes with extremal magnetic charge. Because they don't Hawking radiate, much lighter primordial black holes could exist today if they are extremal. The dominant constraints come from white dwarf destruction for intermediate masses, and intergalactic gas heating for heavier black holes. Extremal magnetic black holes may catalyze proton decay, and thus we derive robust limits -- independent of the catalysis cross section -- from the above as well as from white dwarf heating. We discuss other bounds such as those from neutron star heating, solar neutrino production, binary formation and annihilation into gamma rays, and magnetic field destruction. We note that stable magnetically charged black holes can assist in the formation of neutron star mass black holes., Comment: 48 pages, 6 figures Typos fixed, text edited for brevity and clarity, references added, minor correction in binary merger rate presented in Appendix B which results in slightly stronger constraints on the EMBH abundance from binary mergers, comments added about bounds evolve if the semi-classical description of Hawking radiation breaks down
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- 2021
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185. The Green Bank Northern Celestial Cap Pulsar Survey. VI. Timing and Discovery of PSR J1759+5036: A Double Neutron Star Binary Pulsar
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Agazie, Gabriella, Mingyar, Michael, McLaughlin, Maura, Swiggum, Joseph, Kaplan, David, Blumer, Harsha, Chawla, Pragya, DeCesar, Megan, Demorest, Paul, Fiore, William, Fonseca, Emmanuel, Gelfand, Joseph, Kaspi, Victoria, Kondratiev, Vladislav, LaRose, Malcolm, van Leeuwen, Joeri, Levin, Lina, Lewis, Evan, Lynch, Ryan, McEwen, Alexander, Noori, Hind Al, Parent, Emilie, Ransom, Scott, Roberts, Mallory, Schmiedekamp, Ann, Schmiedekamp, Carl, Siemens, Xavier, Spiewak, Renée, Stairs, Ingrid, and Surnis, Mayuresh
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
The Green Bank North Celestial Cap (GBNCC) survey is a 350-MHz all-sky survey for pulsars and fast radio transients using the Robert C. Byrd Green Bank Telescope. To date, the survey has discovered over 190 pulsars, including 33 millisecond pulsars (MSPs) and 24 rotating radio transients(RRATs). Several exotic pulsars have been discovered in the survey, including PSR J1759+5036, a binary pulsar with a 176-ms spin period in an orbit with a period of 2.04 days, an eccentricity of 0.3,and a projected semi-major axis of 6.8 light seconds. Using seven years of timing data, we are able to measure one post-Keplerian parameter, advance of periastron, which has allowed us to constrain the total system mass to 2.62(3) solar masses. This constraint, along with the spin period and orbital parameters, suggests that this is a double neutron star system, although we cannot entirely rule out a pulsar-white dwarf binary. This pulsar is only detectable in roughly 45% of observations, most likely due to scintillation. However, additional observations are required to determine whether there may be other contributing effects., Comment: 11 pages, 13 figures, Accepted to APJ
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- 2021
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186. A search for radio afterglows from gamma-ray bursts with the Australian Square Kilometre Array Pathfinder
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Leung, James K., Murphy, Tara, Ghirlanda, Giancarlo, Kaplan, David L., Lenc, Emil, Dobie, Dougal, Banfield, Julie, Hale, Catherine, Hotan, Aidan, McConnell, David, Moss, Vanessa A., Pritchard, Joshua, Raja, Wasim, Stewart, Adam J., and Whiting, Matthew
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We present a search for radio afterglows from long gamma-ray bursts using the Australian Square Kilometre Array Pathfinder (ASKAP). Our search used the Rapid ASKAP Continuum Survey, covering the entire celestial sphere south of declination $+41^\circ$, and three epochs of the Variables and Slow Transients Pilot Survey (Phase 1), covering $\sim 5,000$ square degrees per epoch. The observations we used from these surveys spanned a nine-month period from 2019 April 21 to 2020 January 11. We crossmatched radio sources found in these surveys with 779 well-localised (to $\leq 15''$) long gamma-ray bursts occurring after 2004 and determined whether the associations were more likely afterglow- or host-related through the analysis of optical images. In our search, we detected one radio afterglow candidate associated with GRB 171205A, a local low-luminosity gamma-ray burst with a supernova counterpart SN 2017iuk, in an ASKAP observation 511 days post-burst. We confirmed this detection with further observations of the radio afterglow using the Australia Telescope Compact Array at 859 days and 884 days post-burst. Combining this data with archival data from early-time radio observations, we showed the evolution of the radio spectral energy distribution alone could reveal clear signatures of a wind-like circumburst medium for the burst. Finally, we derived semi-analytical estimates for the microphysical shock parameters of the burst: electron power-law index $p = 2.84$, normalised wind-density parameter $A_* = 3$, fractional energy in electrons $\epsilon_{e} = 0.3$, and fractional energy in magnetic fields $\epsilon_{B} = 0.0002$., Comment: 18 pages, 7 figures; accepted for publication in MNRAS
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- 2021
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187. A circular polarisation survey for radio stars with the Australian SKA Pathfinder
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Pritchard, Joshua, Murphy, Tara, Zic, Andrew, Lynch, Christene, Heald, George, Kaplan, David L., Anderson, Craig, Banfield, Julie, Hale, Catherine, Hotan, Aidan, Lenc, Emil, Leung, James K., McConnell, David, Moss, Vanessa A., Raja, Wasim, Stewart, Adam J., and Whiting, Matthew
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Astrophysics - Solar and Stellar Astrophysics - Abstract
We present results from a circular polarisation survey for radio stars in the Rapid ASKAP Continuum Survey (RACS). RACS is a survey of the entire sky south of $\delta=+41^\circ$ being conducted with the Australian Square Kilometre Array Pathfinder telescope (ASKAP) over a 288 MHz wide band centred on 887.5 MHz. The data we analyse includes Stokes I and V polarisation products to an RMS sensitivity of 250 $\mu$Jy PSF$^{-1}$. We searched RACS for sources with fractional circular polarisation above 6 per cent, and after excluding imaging artefacts, polarisation leakage, and known pulsars we identified radio emission coincident with 33 known stars. These range from M-dwarfs through to magnetic, chemically peculiar A- and B-type stars. Some of these are well known radio stars such as YZ CMi and CU Vir, but 23 have no previous radio detections. We report the flux density and derived brightness temperature of these detections and discuss the nature of the radio emission. We also discuss the implications of our results for the population statistics of radio stars in the context of future ASKAP and Square Kilometre Array surveys., Comment: 18 pages, 10 figures, to be published in MNRAS
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- 2021
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188. ASKAP observations of multiple rapid scintillators reveal a degrees-long plasma filament
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Wang, Yuanming, Tuntsov, Artem, Murphy, Tara, Lenc, Emil, Walker, Mark, Bannister, Keith, Kaplan, David L., and Mahony, Elizabeth K.
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present the results from an Australian Square Kilometre Array Pathfinder search for radio variables on timescales of hours. We conducted an untargeted search over a 30 deg$^2$ field, with multiple 10-hour observations separated by days to months, at a central frequency of 945 MHz. We discovered six rapid scintillators from 15-minute model-subtracted images with sensitivity of $\sim 200\,\mu$Jy/beam; two of them are extreme intra-hour variables with modulation indices up to $\sim 40\%$ and timescales as short as tens of minutes. Five of the variables are in a linear arrangement on the sky with angular width $\sim 1$ arcmin and length $\sim 2$ degrees, revealing the existence of a huge plasma filament in front of them. We derived kinematic models of this plasma from the annual modulation of the scintillation rate of our sources, and we estimated its likely physical properties: a distance of $\sim 4$ pc and length of $\sim 0.1$ pc. The characteristics we observe for the scattering screen are incompatible with published suggestions for the origin of intra-hour variability leading us to propose a new picture in which the underlying phenomenon is a cold tidal stream. This is the first time that multiple scintillators have been detected behind the same plasma screen, giving direct insight into the geometry of the scattering medium responsible for enhanced scintillation., Comment: 20 pages, 16 figures; accepted for publication in MNRAS
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- 2021
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189. A scalable transient detection pipeline for the Australian SKA Pathfinder VAST survey
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Pintaldi, Sergio, Stewart, Adam, O'Brien, Andrew, Kaplan, David, and Murphy, Tara
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
The Australian Square Kilometre Array Pathfinder (ASKAP) collects images of the sky at radio wavelengths with an unprecedented field of view, combined with a high angular resolution and sub-millijansky sensitivities. The large quantity of data produced is used by the ASKAP Variables and Slow Transients (VAST) survey science project to study the dynamic radio sky. Efficient pipelines are vital in such research, where searches often form a `needle in a haystack' type of problem to solve. However, the existing pipelines developed among the radio-transient community are not suitable for the scale of ASKAP datasets. In this paper we provide a technical overview of the new "VAST Pipeline": a modern and scalable Python-based data pipeline for transient searches, using up-to-date dependencies and methods. The pipeline allows source association to be performed at scale using the Pandas DataFrame interface and the well-known Astropy crossmatch functions. The Dask Python framework is used to parallelise operations as well as scale them both vertically and horizontally, by means of a cluster of workers. A modern web interface for data exploration and querying has also been developed using the latest Django web framework combined with Bootstrap., Comment: 10 pages, to appear in the proceedings of Astronomical Data Analysis Software and Systems XXX published by ASP
- Published
- 2021
190. The NANOGrav 11yr Data Set: Limits on Supermassive Black Hole Binaries in Galaxies within 500Mpc
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Arzoumanian, Zaven, Baker, Paul T., Brazier, Adam, Brook, Paul R., Burke-Spolaor, Sarah, Becsy, Bence, Charisi, Maria, Chatterjee, Shami, Cordes, James M., Cornish, Neil J., Crawford, Fronefield, Cromartie, H. Thankful, DeCesar, Megan E., Demorest, Paul B., Dolch, Timothy, Elliott, Rodney D., Ellis, Justin A., Ferrara, Elizabeth C., Fonseca, Emmanuel, Garver-Daniels, Nathan, Gentile, Peter A., Good, Deborah C., Hazboun, Jeffrey S., Islo, Kristina, Jennings, Ross J., Jones, Megan L., Kaiser, Andrew R., Kaplan, David L., Kelley, Luke Z., Key, Joey Shapiro, Lam, Michael T., Lazio, T. Joseph W., Luo, Jing, Lynch, Ryan S., Ma, Chung-Pei, Madison, Dustin R., McLaughlin, Maura A., Mingarelli, Chiara M. F., Ng, Cherry, Nice, David J., Pennucci, Timothy T., Pol, Nihan S., Ransom, Scott M., Ray, Paul S., Shapiro-Albert, Brent J., Siemens, Xavier, Simon, Joseph, Spiewak, Renee, Stairs, Ingrid H., Stinebring, Daniel R., Stovall, Kevin, Swiggum, Joseph K., Taylor, Stephen R., Vallisneri, Michele, Vigeland, Sarah J., Witt, Caitlin A., and Collaboration, The NANOGrav
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Supermassive black hole binaries (SMBHBs) should form frequently in galactic nuclei as a result of galaxy mergers. At sub-parsec separations, binaries become strong sources of low-frequency gravitational waves (GWs), targeted by Pulsar Timing Arrays (PTAs). We used recent upper limits on continuous GWs from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) 11yr dataset to place constraints on putative SMBHBs in nearby massive galaxies. We compiled a comprehensive catalog of ~44,000 galaxies in the local universe (up to redshift ~0.05) and populated them with hypothetical binaries, assuming that the total mass of the binary is equal to the SMBH mass derived from global scaling relations. Assuming circular equal-mass binaries emitting at NANOGrav's most sensitive frequency of 8nHz, we found that 216 galaxies are within NANOGrav's sensitivity volume. We ranked the potential SMBHBs based on GW detectability by calculating the total signal-to-noise ratio (S/N) such binaries would induce within the NANOGrav array. We placed constraints on the chirp mass and mass ratio of the 216 hypothetical binaries. For 19 galaxies, only very unequal-mass binaries are allowed, with the mass of the secondary less than 10 percent that of the primary, roughly comparable to constraints on a SMBHB in the Milky Way. Additionally, we were able to exclude binaries delivered by major mergers (mass ratio of at least 1/4) for several of these galaxies. We also derived the first limit on the density of binaries delivered by major mergers purely based on GW data., Comment: Submitted to ApJ. Send comments to Maria Charisi (maria.charisi@nanograv.org)
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- 2021
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191. Dark Energy Radiation
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Berghaus, Kim V., Graham, Peter W., Kaplan, David E., Moore, Guy D., and Rajendran, Surjeet
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High Energy Physics - Phenomenology ,Astrophysics - Cosmology and Nongalactic Astrophysics ,High Energy Physics - Theory - Abstract
We show that if dark energy evolves in time, its dynamical component could be dominated by a bath of dark radiation. Within current constraints this radiation could have up to $\sim 10^4$ times more energy density than the cosmic microwave background. We demonstrate particular models in which a rolling scalar field generates different forms of dark radiation such as hidden photons, milli-charged particles and even Standard Model neutrinos. We find the leading effect on the late-time cosmological expansion history depends on a single parameter beyond $\Lambda$CDM, namely the temperature of the dark radiation today. Cosmological observations of this modified expansion rate could provide a striking signature of this scenario. The dark radiation itself could even be directly detectable in laboratory experiments, suggesting a broader experimental program into the nature of dark energy., Comment: 12 pages, 1 Figure
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- 2020
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192. A Flare-Type IV Burst Event from Proxima Centauri and Implications for Space Weather
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Zic, Andrew, Murphy, Tara, Lynch, Christene, Heald, George, Lenc, Emil, Kaplan, David L., Cairns, Iver H., Coward, David, Gendre, Bruce, Johnston, Helen, MacGregor, Meredith, Price, Danny C., and Wheatland, Michael S.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Studies of solar radio bursts play an important role in understanding the dynamics and acceleration processes behind solar space weather events, and the influence of solar magnetic activity on solar system planets. Similar low-frequency bursts detected from active M-dwarfs are expected to probe their space weather environments and therefore the habitability of their planetary companions. Active M-dwarfs produce frequent, powerful flares which, along with radio emission, reveal conditions within their atmospheres. However, to date, only one candidate solar-like coherent radio burst has been identified from these stars, preventing robust observational constraints on their space weather environment. During simultaneous optical and radio monitoring of the nearby dM5.5e star Proxima Centauri, we detected a bright, long-duration optical flare, accompanied by a series of intense, coherent radio bursts. These detections include the first example of an interferometrically detected coherent stellar radio burst temporally coincident with a flare, strongly indicating a causal relationship between these transient events. The polarization and temporal structure of the trailing long-duration burst enable us to identify it as a type IV burst. This represents the most compelling detection of a solar-like radio burst from another star to date. Solar type IV bursts are strongly associated with space weather events such as coronal mass ejections and solar energetic particle events, suggesting that stellar type IV bursts may be used as a tracer of stellar coronal mass ejections. We discuss the implications of this event for the occurrence of coronal mass ejections from Proxima Cen and other active M-dwarfs., Comment: 18 pages, 7 figures, 1 table. Published in the Astrophysical Journal
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- 2020
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193. Astrophysics Milestones For Pulsar Timing Array Gravitational Wave Detection
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Pol, Nihan S., Taylor, Stephen R., Kelley, Luke Zoltan, Vigeland, Sarah J., Simon, Joseph, Chen, Siyuan, Arzoumanian, Zaven, Baker, Paul T., Bécsy, Bence, Brazier, Adam, Brook, Paul R., Burke-Spolaor, Sarah, Chatterjee, Shami, Cordes, James M., Cornish, Neil J., Crawford, Fronefield, Cromartie, H. Thankful, DeCesar, Megan E., Demorest, Paul B., Dolch, Timothy, Ferrara, Elizabeth C., Fiore, William, Fonseca, Emmanuel, Garver-Daniels, Nathan, Good, Deborah C., Hazboun, Jeffrey S., Jennings, Ross J., Jones, Megan L., Kaiser, Andrew R., Kaplan, David L., Key, Joey Shapiro, Lam, Michael T., Lazio, T. Joseph W., Luo, Jing, Lynch, Ryan S., Madison, Dustin R., McEwen, Alexander, McLaughlin, Maura A., Mingarelli, Chiara M. F., Ng, Cherry, Nice, David J., Pennucci, Timothy T., Ransom, Scott M., Ray, Paul S., Shapiro-Albert, Brent J., Siemens, Xavier, Stairs, Ingrid H., Stinebring, Daniel R., Swiggum, Joseph K., Vallisneri, Michele, Wahl, Haley, and Witt, Caitlin A.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies ,General Relativity and Quantum Cosmology - Abstract
The NANOGrav Collaboration reported strong Bayesian evidence for a common-spectrum stochastic process in its 12.5-yr pulsar timing array dataset, with median characteristic strain amplitude at periods of a year of $A_{\rm yr} = 1.92^{+0.75}_{-0.55} \times 10^{-15}$. However, evidence for the quadrupolar Hellings \& Downs interpulsar correlations, which are characteristic of gravitational wave signals, was not yet significant. We emulate and extend the NANOGrav dataset, injecting a wide range of stochastic gravitational wave background (GWB) signals that encompass a variety of amplitudes and spectral shapes, and quantify three key milestones: (I) Given the amplitude measured in the 12.5 yr analysis and assuming this signal is a GWB, we expect to accumulate robust evidence of an interpulsar-correlated GWB signal with 15--17 yrs of data, i.e., an additional 2--5 yrs from the 12.5 yr dataset; (II) At the initial detection, we expect a fractional uncertainty of $40\%$ on the power-law strain spectrum slope, which is sufficient to distinguish a GWB of supermassive black-hole binary origin from some models predicting more exotic origins;(III) Similarly, the measured GWB amplitude will have an uncertainty of $44\%$ upon initial detection, allowing us to arbitrate between some population models of supermassive black-hole binaries. In addition, power-law models are distinguishable from those having low-frequency spectral turnovers once 20~yrs of data are reached. Even though our study is based on the NANOGrav data, we also derive relations that allow for a generalization to other pulsar-timing array datasets. Most notably, by combining the data of individual arrays into the International Pulsar Timing Array, all of these milestones can be reached significantly earlier., Comment: 15 pages, 7 figures
- Published
- 2020
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194. The capability of the Australian Square Kilometre Array Pathfinder to detect prompt radio bursts from neutron star mergers
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Wang, Ziteng, Murphy, Tara, Kaplan, David L., Bannister, Keith W., and Dobie, Dougal
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We discuss observational strategies to detect prompt bursts associated with gravitational wave events using the Australian Square Kilometre Array Pathfinder (ASKAP). Many theoretical models of binary neutron stars mergers predict that bright, prompt radio emission would accompany the merger. The detection of such prompt emission would greatly improve our knowledge of the physical conditions, environment, and location of the merger. However, searches for prompt emission are complicated by the relatively poor localisation for gravitational wave events, with the 90\% credible region reaching hundreds or even thousands of square degrees. Operating in fly's eye mode, the ASKAP field of view can reach $\sim$1000 deg$^2$ at $\sim 888\,{\rm MHz}$. This potentially allows observers to cover most of the 90\% credible region quickly enough to detect prompt emission. We use skymaps for GW170817 and GW190814 from LIGO/Virgo's third observing run to simulate the probability of detecting prompt emission for gravitational wave events in the upcoming fourth observing run. With only alerts released after merger we find it difficult to slew the telescope sufficiently quickly as to capture any prompt emission. However, with the addition of alerts released \textit{before} merger by negative-latency pipelines we find that it should be possible to search for nearby, bright prompt FRB-like emission from gravitational wave events. Nonetheless, the rates are low: we would expect to observe $\sim$0.012 events during the fourth observing run, assuming that the prompt emission is emitted microseconds around the merger, Comment: 8 pages, 4 figures
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- 2020
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195. Interpreting Unconditional Quantile Regression with Conditional Independence
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Kaplan, David M.
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Economics - Econometrics - Abstract
This note provides additional interpretation for the counterfactual outcome distribution and corresponding unconditional quantile "effects" defined and estimated by Firpo, Fortin, and Lemieux (2009) and Chernozhukov, Fern\'andez-Val, and Melly (2013). With conditional independence of the policy variable of interest, these methods estimate the policy effect for certain types of policies, but not others. In particular, they estimate the effect of a policy change that itself satisfies conditional independence., Comment: The main result is essentially the same as Proposition 1 of Rothe (2010), https://doi.org/10.1016/j.jeconom.2009.09.001
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- 2020
196. Searching for New Interactions at Sub-micron Scale Using the Mossbauer Effect
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Gratta, Giorgio, Kaplan, David E., and Rajendran, Surjeet
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Theory ,Nuclear Experiment - Abstract
A new technique to search for new scalar and tensor interactions at the sub-micrometer scale is presented. The technique relies on small shifts of nuclear gamma lines produced by the coupling between matter and the nuclei in the source or absorber of a Mossbauer spectrometer. Remarkably, such energy shifts are rather insensitive to electromagnetic interactions that represent the largest background in searches for new forces using atomic matter. This is because nuclei are intrinsically shielded by the electron clouds. Additionally, electromagnetic interactions cause energy shifts by coupling to nuclear moments that are suppressed by the size of the nuclei, while new scalar interactions can directly affect these shifts. Finally, averaging over unpolarized nuclei, further reduces electromagnetic interactions. We discuss several possible configurations, using the traditional Mossbauer effect as well as nuclear resonant absorption driven by synchrotron radiation. For this purpose, we examine the viability of well known Mossbauer nuclides along with more exotic ones that result in substantially narrower resonances. We find that the technique introduced here could substantially improve the sensitivity to a variety of new interactions and could also be used, in conjunction with mechanical force measurements, to corroborate a discovery or explore the new physics that may be behind a discovery., Comment: 11 pages, 7 figures
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- 2020
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197. An 8.8 minute orbital period eclipsing detached double white dwarf binary
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Burdge, Kevin B., Coughlin, Michael W., Fuller, Jim, Kaplan, David L., Kulkarni, S. R., Marsh, Thomas R., Prince, Thomas A., Bellm, Eric C., Dekany, Richard G., Duev, Dmitry A., Graham, Matthew J., Mahabal, Ashish A., Masci, Frank J., Laher, Russ R., Riddle, Reed, and Soumagnac, Maayane T.
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report the discovery of ZTF J2243+5242, an eclipsing double white dwarf binary with an orbital period of just $8.8$ minutes, the second known eclipsing binary with an orbital period less than ten minutes. The system likely consists of two low-mass white dwarfs, and will merge in approximately 400,000 years to form either an isolated hot subdwarf or an R Coronae Borealis star. Like its $6.91\, \rm min$ counterpart, ZTF J1539+5027, ZTF J2243+5242 will be among the strongest gravitational wave sources detectable by the space-based gravitational-wave detector The Laser Space Interferometer Antenna (LISA) because its gravitational-wave frequency falls near the peak of LISA's sensitivity. Based on its estimated distance of $d=2120^{+131}_{-115}\,\rm pc$, LISA should detect the source within its first few months of operation, and should achieve a signal-to-noise ratio of $87\pm5$ after four years. We find component masses of $M_A= 0.349^{+0.093}_{-0.074}\,M_\odot$ and $M_B=0.384^{+0.114}_{-0.074}\,M_\odot$, radii of $R_A=0.0308^{+0.0026}_{-0.0025}\,R_\odot$ and $R_B = 0.0291^{+0.0032}_{-0.0024}\,R_\odot$, and effective temperatures of $T_A=22200^{+1800}_{-1600}\,\rm K$ and $T_B=16200^{+1200}_{-1000}\,\rm K$. We determined all of these properties, and the distance to this system, using only photometric measurements, demonstrating a feasible way to estimate parameters for the large population of optically faint ($r>21 \, m_{\rm AB}$) gravitational-wave sources which the Vera Rubin Observatory (VRO) and LISA should identify., Comment: 12 pages, 7 figures, 3 tables, submitted
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- 2020
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198. Development and Implementation of Multidisciplinary Liver Tumor Boards in the Veterans Affairs Health Care System: A 10-Year Experience.
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Rabiee, Atoosa, Taddei, Tamar, Aytaman, Ayse, Rogal, Shari S, Kaplan, David E, and Morgan, Timothy R
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hepatocellular carcinoma ,tumor board ,veterans affairs ,Clinical Research ,Cancer ,Digestive Diseases ,Health Services ,Liver Disease ,Clinical Trials and Supportive Activities ,8.1 Organisation and delivery of services ,Oncology and Carcinogenesis - Abstract
In this perspective piece, we summarize the development and implementation of multidisciplinary liver tumor boards across the Veterans Affairs health care system dating back to 2010. Referral to multidisciplinary tumor boards (MDLTB) has been demonstrated to decrease the number of unnecessary invasive procedures, reduce health care costs and maximize patient outcomes. Although the VA is the largest single care provider in the US, there is significant heterogeneity in healthcare delivery. We have shown that receiving care at VA centers with MDLTB is associated with higher odds of receiving active therapy and a 13% reduction in mortality. Access to expert hepatology care appears to be one of the critical benefits of MDLTB resulting in 30% reduction in mortality. Integrated health care systems such as the VA have the unique capability of implementing virtual tumor boards that can easily overcome geographic barriers and standardize care across multiple facilities regardless of their access to hepatology or other disciplines. Significant barriers remain requiring implementation plans. This document serves as a roadmap to establish multidisciplinary tumor boards, including standardization of imaging reports, identifying stake holders who need to be present at tumor board, institution buy-in, and specifics for local, regional and integrated service network tumor boards.
- Published
- 2021
199. Bayesian Dynamic Borrowing of Historical Information with Applications to the Analysis of Large-Scale Assessments
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Kaplan, David, Chen, Jianshen, Yavuz, Sinan, and Lyu, Weicong
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- 2023
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200. Hierarchically structured bioinspired nanocomposites
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Nepal, Dhriti, Kang, Saewon, Adstedt, Katarina M., Kanhaiya, Krishan, Bockstaller, Michael R., Brinson, L. Catherine, Buehler, Markus J., Coveney, Peter V., Dayal, Kaushik, El-Awady, Jaafar A., Henderson, Luke C., Kaplan, David L., Keten, Sinan, Kotov, Nicholas A., Schatz, George C., Vignolini, Silvia, Vollrath, Fritz, Wang, Yusu, Yakobson, Boris I., Tsukruk, Vladimir V., and Heinz, Hendrik
- Published
- 2023
- Full Text
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