71,512 results on '"Hodge, A"'
Search Results
2. Elementary Teachers' Use of Adaptive Diagnostic Assessment to Improve Mathematics Teaching and Learning: A Case Study
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Dalal H. Alfageh, Cindy S. York, Angie Hodge-Zickerman, and Ying Xie
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This case study examined teachers' perceptions and use of adaptive diagnostic assessment for improving teaching and learning of elementary-level mathematics. The purpose was to understand how the teaching and learning of mathematics occurred in the classroom and changes that transpired due to the implementation of diagnostic assessments. Findings illustrate that diagnostic assessment can be a critical tool for improving pedagogical practice by enhancing mathematics teaching and learning by creating groups of students, planning lesson time, focused pedagogy, giving student feedback, communicating with stakeholders, and improving teacher efficiency. Participants demonstrated satisfaction with the benefits offered by diagnostic assessment for improving mathematics teaching and learning. Participants described challenges that hindered their effective use of diagnostic assessment tools. The findings of this study support a case for the adoption of diagnostic assessments to improve pedagogical practice and promote mathematics learning among elementary-level students.
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- 2024
3. Preferential Occurrence of Fast Radio Bursts in Massive Star-Forming Galaxies
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Sharma, Kritti, Ravi, Vikram, Connor, Liam, Law, Casey, Ocker, Stella Koch, Sherman, Myles, Kosogorov, Nikita, Faber, Jakob, Hallinan, Gregg, Harnach, Charlie, Hellbourg, Greg, Hobbs, Rick, Hodge, David, Hodges, Mark, Lamb, James, Rasmussen, Paul, Somalwar, Jean, Weinreb, Sander, Woody, David, Leja, Joel, Anand, Shreya, Das, Kaustav Kashyap, Qin, Yu-Jing, Rose, Sam, Dong, Dillon Z., Miller, Jessie, and Yao, Yuhan
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies - Abstract
Fast Radio Bursts (FRBs) are millisecond-duration events detected from beyond the Milky Way. FRB emission characteristics favor highly magnetized neutron stars, or magnetars, as the sources, as evidenced by FRB-like bursts from a galactic magnetar, and the star-forming nature of FRB host galaxies. However, the processes that produce FRB sources remain unknown. Although galactic magnetars are often linked to core-collapse supernovae (CCSNe), it's uncertain what determines which supernovae result in magnetars. The galactic environments of FRB sources can be harnessed to probe their progenitors. Here, we present the stellar population properties of 30 FRB host galaxies discovered by the Deep Synoptic Array. Our analysis shows a significant deficit of low-mass FRB hosts compared to the occurrence of star-formation in the universe, implying that FRBs are a biased tracer of star-formation, preferentially selecting massive star-forming galaxies. This bias may be driven by galaxy metallicity, which is positively correlated with stellar mass. Metal-rich environments may favor the formation of magnetar progenitors through stellar mergers, as higher metallicity stars are less compact and more likely to fill their Roche lobes, leading to unstable mass transfer. Although massive stars do not have convective interiors to generate strong magnetic fields by dynamo, merger remnants are thought to have the requisite internal magnetic-field strengths to result in magnetars. The preferential occurrence of FRBs in massive star-forming galaxies suggests that CCSN of merger remnants preferentially forms magnetars., Comment: Accepted for publication in Nature. The final version will be published by the journal
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- 2024
4. A gas rich cosmic web revealed by partitioning the missing baryons
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Connor, Liam, Ravi, Vikram, Sharma, Kritti, Ocker, Stella Koch, Faber, Jakob, Hallinan, Gregg, Harnach, Charlie, Hellbourg, Greg, Hobbs, Rick, Hodge, David, Hodges, Mark, Kosogorov, Nikita, Lamb, James, Law, Casey, Rasmussen, Paul, Sherman, Myles, Somalwar, Jean, Weinreb, Sander, and Woody, David
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Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Approximately half of the Universe's dark matter resides in collapsed halos; significantly less than half of the baryonic matter (protons and neutrons) remains confined to halos. A small fraction of baryons are in stars and the interstellar medium within galaxies. The lion's share are diffuse (less than $10^{-3}$ cm$^{-3}$) and ionized (neutral fraction less than $10^{-4}$), located in the intergalactic medium (IGM) and in the halos of galaxy clusters, groups, and galaxies. The quantity and spatial distribution of this diffuse ionized gas is notoriously difficult to measure, but has wide implications for galaxy formation, astrophysical feedback, and precision cosmology. Recently, the dispersion of extragalactic Fast Radio Bursts (FRBs) has been used to measure the total content of cosmic baryons. However, past efforts had modest samples and methods that cannot discriminate between IGM and halo gas, which is critical for studying feedback and for observational cosmology. Here, we present a large cosmological sample of FRB sources localized to their host galaxies. We have robustly partitioned the missing baryons into the IGM, galaxy clusters, and galaxies, providing a late-Universe measurement of the total baryon density of $\Omega_b h_{70}$=0.049$\pm$0.003. Our results indicate efficient feedback processes that can expel gas from galaxy halos and into the intergalactic medium, agreeing with the enriched cosmic web scenario seen in cosmological simulations. The large diffuse baryon fraction that we have measured disfavours bottom-heavy stellar initial mass functions, which predict a large total stellar density, $\Omega_*$.
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- 2024
5. Characterizing the contribution of dust-obscured star formation at $z \gtrsim$ 5 using 18 serendipitously identified [CII] emitters
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van Leeuwen, I. F., Bouwens, R. J., van der Werf, P. P., Hodge, J. A., Schouws, S., Stefanon, M., Algera, H. S. B., Aravena, M., Boogaard, L. A., Bowler, R. A . A., da Cunha, E., Dayal, P., Decarli, R., Gonzalez, V., Inami, H., de Looze, I., Sommovigo, L., Venemans, B. P., Walter, F., Barrufet, L., Ferrara, A., Graziani, L., Hygate, A. P. S., Oesch, P., Palla, M., Rowland, L., and Schneider, R.
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Astrophysics - Astrophysics of Galaxies - Abstract
We present a new method to determine the star formation rate (SFR) density of the Universe at $z \gtrsim 5$ that includes the contribution of dust-obscured star formation. For this purpose, we use a [CII] (158 $\mu$m) selected sample of galaxies serendipitously identified in the fields of known $z\gtrsim 4.5$ objects to characterize the fraction of obscured SFR. The advantage of a [CII] selection is that our sample is SFR-selected, in contrast to a UV-selection that would be biased towards unobscured star formation. We obtain a sample of 23 [CII] emitters near star-forming (SF) galaxies and QSOs -- three of which we identify for the first time -- using previous literature and archival ALMA data. 18 of these serendipitously identified galaxies have sufficiently deep rest-UV data and are used to characterize the obscured fraction of the star formation in galaxies with SFRs $\gtrsim 30\ \text{M}_{\odot} \ \text{yr}^{-1}$. We find that [CII] emitters identified around SF galaxies have $\approx$63\% of their SFR obscured, while [CII] emitters around QSOs have $\approx$93\% of their SFR obscured. By forward modeling existing wide-area UV luminosity function (LF) determinations, we derive the intrinsic UV LF using our characterization of the obscured SFR. Integrating the intrinsic LF to $M_{UV}$ = $-$20 we find that the obscured SFRD contributes to $>3\%$ and $>10\%$ of the total SFRD at $z \sim 5$ and $z \sim 6$ based on our sample of companions galaxies near SFGs and QSOs, respectively. Our results suggest that dust obscuration is not negligible at $z\gtrsim 5$, further underlining the importance of far-IR observations of the $z\gtrsim 5$ Universe., Comment: Accepted for publication in MNRAS. 24 pages, 14 figures, 8 tables (including appendices)
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- 2024
6. The ALMA-CRISTAL Survey: Spatially-resolved Star Formation Activity and Dust Content in 4 < z < 6 Star-forming Galaxies
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Li, Juno, Da Cunha, Elisabete, González-López, Jorge, Aravena, Manuel, De Looze, Ilse, Schreiber, N. M. Förster, Herrera-Camus, Rodrigo, Spilker, Justin, Tadaki, Ken-ichi, Barcos-Munoz, Loreto, Battisti, Andrew J., Birkin, Jack E., Bowler, Rebecca A. A., Davies, Rebecca, Díaz-Santos, Tanio, Ferrara, Andrea, Fisher, Deanne B., Hodge, Jacqueline, Ikeda, Ryota, Killi, Meghana, Lee, Lilian, Liu, Daizhong, Lutz, Dieter, Mitsuhashi, Ikki, Naab, Thorsten, Posses, Ana, Relaño, Monica, Solimano, Manuel, Übler, Hannah, van der Giessen, Stefan Anthony, and Villanueva, Vicente
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Astrophysics - Astrophysics of Galaxies - Abstract
Using a combination of HST, JWST, and ALMA data, we perform spatially resolved spectral energy distributions (SED) fitting of fourteen 4
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- 2024
7. GRB 221009A: the B.O.A.T Burst that Shines in Gamma Rays
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Axelsson, M., Ajello, M., Arimoto, M., Baldini, L., Ballet, J., Baring, M. G., Bartolini, C., Bastieri, D., Gonzalez, J. Becerra, Bellazzini, R., Berenji, B., Bissaldi, E., Blandford, R. D., Bonino, R., Bruel, P., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Cavazzuti, E., Cheung, C. C., Chiaro, G., Cibrario, N., Ciprini, S., Cozzolongo, G., Orestano, P. Cristarella, Crnogorcevic, M., Cuoco, A., Cutini, S., D'Ammando, F., De Gaetano, S., Di Lalla, N., Dinesh, A., Di Tria, R., Di Venere, L., Domínguez, A., Fegan, S. J., Ferrara, E. C., Fiori, A., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Galanti, G., Gargano, F., Gasbarra, C., Germani, S., Giacchino, F., Giglietto, N., Giliberti, M., Gill, R., Giordano, F., Giroletti, M., Granot, J., Green, D., Grenier, I. A., Guiriec, S., Gustafsson, M., Hashizume, M., Hays, E., Hewitt, J. W., Horan, D., Kayanoki, T., Kuss, M., Laviron, A., Li, J., Liodakis, I., Longo, F., Loparco, F., Lorusso, L., Lott, B., Lovellette, M. N., Lubrano, P., Maldera, S., Malyshev, D., Manfreda, A., Martí-Devesa, G., Martinelli, R., Castellanos, I. Martinez, Mazziotta, M. N., McEnery, J. E., Mereu, I., Meyer, M., Michelson, P. F., Mirabal, N., Mitthumsiri, W., Mizuno, T., Monti-Guarnieri, P., Monzani, M. E., Morishita, T., Morselli, A., Moskalenko, I. V., Negro, M., Niwa, R., Omodei, N., Orienti, M., Orlando, E., Paneque, D., Panzarini, G., Persic, M., Pesce-Rollins, M., Petrosian, V., Pillera, R., Piron, F., Porter, T. A., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ryde, F., Sánchez-Conde, M., Parkinson, P. M. Saz, Serini, D., Sgrò, C., Sharma, V., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Tak, D., Thayer, J. B., Torres, D. F., Valverde, J., Zaharijas, G., Lesage, S., Briggs, M. S., Burns, E., Bala, S., Bhat, P. N., Cleveland, W. H., Dalessi, S., de Barra, C., Gibby, M., Giles, M. M., Hamburg, R., Hristov, B. A., Hui, C. M., Kocevski, D., Mailyan, B., Malacaria, C., McBreen, S., Poolakkil, S., Roberts, O. J., Scotton, L., Veres, P., von Kienlin, A., Wilson-Hodge, C. A., and Wood, J.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a complete analysis of Fermi Large Area Telescope (LAT) data of GRB 221009A, the brightest Gamma-Ray Burst (GRB) ever detected. The burst emission above 30 MeV detected by the LAT preceded by 1 s the low-energy (< 10 MeV) pulse that triggered the Fermi Gamma-Ray Burst Monitor (GBM), as has been observed in other GRBs. The prompt phase of GRB 221009A lasted a few hundred seconds. It was so bright that we identify a Bad Time Interval (BTI) of 64 seconds caused by the extremely high flux of hard X-rays and soft gamma rays, during which the event reconstruction efficiency was poor and the dead time fraction quite high. The late-time emission decayed as a power law, but the extrapolation of the late-time emission during the first 450 seconds suggests that the afterglow started during the prompt emission. We also found that high-energy events observed by the LAT are incompatible with synchrotron origin, and, during the prompt emission, are more likely related to an extra component identified as synchrotron self-Compton (SSC). A remarkable 400 GeV photon, detected by the LAT 33 ks after the GBM trigger and directionally consistent with the location of GRB 221009A, is hard to explain as a product of SSC or TeV electromagnetic cascades, and the process responsible for its origin is uncertain. Because of its proximity and energetic nature, GRB 221009A is an extremely rare event., Comment: 60 pages, 38 figures, 9 tables
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- 2024
8. The Extended Mapping Obscuration to Reionization with ALMA (Ex-MORA) Survey: 5$\sigma$ Source Catalog and Redshift Distribution
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Long, Arianna S., Casey, Caitlin M., McKinney, Jed, Zavala, Jorge A., Akins, Hollis B., Cooper, Olivia R., Lambrides, Matthieu Bethermin Erini L., Franco, Maximilien, Caputi, Karina, Champagne, Jaclyn B., Man, Allison W. S., Treister, Ezequiel, Manning, Sinclaire M., Sanders, David B., Talia, Margherita, Aravena, Manuel, Clements, D. L., da Cunha, Elisabete, Faisst, Andreas L., Gentile, Fabrizio, Hodge, Jacqueline, Brammer, Gabriel, Brusa, Marcella, Finkelstein, Steven L., Fujimoto, Seiji, Hayward, Christopher C., Ilbert, Olivier, Jolly, Jean-Baptiste, Kartaltepe, Jeyhan S., Knudsen, Kirsten, Koekemoer, Anton M., Liu, Daizhong, Magdis, Georgios, McCracken, Henry Joy, Rhodes, Jason, Robertson, Brant E., Scoville, Nick, Sheth, Kartik, Smolcic, Vernesa, Spilker, Justin, Taniguchi, Yoshiaki, Toft, Sune, Urry, C. Megan, and Yun, Min
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Astrophysics - Astrophysics of Galaxies - Abstract
One of the greatest challenges in galaxy evolution over the last decade has been constraining the prevalence of heavily dust-obscured galaxies in the early Universe. At $z>3$, these galaxies are increasingly rare, and difficult to identify as they are interspersed among the more numerous dust-obscured galaxy population at $z=1-3$, making efforts to secure confident spectroscopic redshifts expensive, and sometimes unsuccessful. In this work, we present the Extended Mapping Obscuration to Reionization with ALMA (Ex-MORA) Survey -- a 2mm blank-field survey in the COSMOS-Web field, and the largest ever ALMA blank-field survey to-date covering 577 arcmin$^2$. Ex-MORA is an expansion of the MORA survey designed to identify primarily $z>3$ dusty, star-forming galaxies while simultaneously filtering out the more numerous $z<3$ population by leveraging the very negative $K$-correction at observed-frame 2mm. We identify 37 significant ($>$5$\sigma$) sources, 33 of which are robust thermal dust emitters. We measure a median redshift of $\langle z \rangle = 3.6^{+0.1}_{-0.2}$, with two-thirds of the sample at $z>3$, and just under half at $z>4$, demonstrating the overall success of the 2mm-selection technique. The integrated $z>3$ volume density of Ex-MORA sources is $\sim1-3\times10^{-5}$ Mpc$^{-3}$, consistent with other surveys of infrared luminous galaxies at similar epochs. We also find that techniques using rest-frame optical emission (or lack thereof) to identify $z>3$ heavily dust-obscured galaxies miss at least half of Ex-MORA galaxies. This supports the idea that the dusty galaxy population is heterogeneous, and that synergies across observatories spanning multiple energy regimes are critical to understanding their formation and evolution at $z>3$., Comment: 13 pages, 5 figures, submitted to ApJ; fully reduced mosaic will be shared upon publication
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- 2024
9. Autonomous Grid-Forming Inverter Exponential Droop Control for Improved Frequency Stability
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Kenyon, Rick Wallace, Sajadi, Amirhossein, and Hodge, Bri-Mathias
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Electrical Engineering and Systems Science - Systems and Control - Abstract
This paper introduces the novel Droop-e grid-forming power electronic converter control strategy, which establishes a non-linear, active power--frequency droop relationship based on an exponential function of the power output. A primary advantage of Droop-e is an increased utilization of available power headroom that directly mitigates system frequency excursions and reduces the rate of change of frequency. The motivation for Droop-e as compared to a linear grid-forming control is first established, and then the full controller is described, including the mirrored inversion at the origin, the linearization at a parameterized limit, and the auxiliary autonomous power sharing controller. The analytic stability of the controller, including synchronization criteria and a small signal stability analysis, is assessed. Electromagnetic transient time domain simulations of the Droop-e controller with full order power electronic converters and accompanying DC-side dynamics, connected in parallel with synchronous generators, are executed at a range of dispatches on a simple 3-bus system. Finally, IEEE 39-bus system simulations highlight the improved frequency stability of the system with multiple, Droop-e controlled grid-forming inverters., Comment: 10 pages, 11 figures
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- 2024
10. Accurate Simultaneous Constraints on the Dust Mass, Temperature and Emissivity Index of a Galaxy at Redshift 7.31
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Algera, Hiddo, Inami, Hanae, De Looze, Ilse, Ferrara, Andrea, Hirashita, Hiroyuki, Aravena, Manuel, Bakx, Tom, Bouwens, Rychard, Bowler, Rebecca, Da Cunha, Elisabete, Dayal, Pratika, Fudamoto, Yoshinobu, Hodge, Jacqueline, Hygate, Alexander, van Leeuwen, Ivana, Nanayakkara, Themiya, Palla, Marco, Pallottini, Andrea, Rowland, Lucie, Smit, Renske, Sommovigo, Laura, Stefanon, Mauro, Vijayan, Aswin, and van der Werf, Paul
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Astrophysics - Astrophysics of Galaxies - Abstract
We present new multi-frequency ALMA continuum observations of the massive [$\log_{10}(M_\star/M_\odot) = 10.3_{-0.2}^{+0.1}$], UV-luminous [$M_\mathrm{UV} = -21.7 \pm 0.2$] $z=7.31$ galaxy REBELS-25 in Bands 3, 4, 5, and 9. Combining the new observations with previously-taken data in Bands 6 and 8, we cover the dust continuum emission of the galaxy in six distinct bands -- spanning rest-frame $50-350\,\mu$m -- enabling simultaneous constraints on its dust mass ($M_\mathrm{dust}$), temperature ($T_\mathrm{dust}$) and emissivity index ($\beta_\mathrm{IR}$) via modified blackbody fitting. Given a fiducial model of optically thin emission, we infer a cold dust temperature of $T_\mathrm{dust} = 32_{-6}^{+9}\,$K and a high dust mass of $\log_{10}(M_\mathrm{dust}/M_\odot) = 8.2_{-0.4}^{+0.6}$, and moderately optically thick dust does not significantly alter these estimates. If we assume dust production is solely through supernovae (SNe), the inferred dust yield would be high, $y = 0.7_{-0.4}^{+2.3}\,M_\odot$ per SN. Consequently, we argue grain growth in the interstellar medium of REBELS-25 also contributes to its dust build-up. This is supported by the steep dust emissivity index $\beta_\mathrm{IR} = 2.5 \pm 0.4$ we measure for REBELS-25, as well as by its high stellar mass, dense interstellar medium, and metal-rich nature. Our results suggest that constraining the dust emissivity indices of high-redshift galaxies is important not only to mitigate systematic uncertainties in their dust masses and obscured star formation rates, but also to assess if dust properties evolve across cosmic time. We present an efficient observing setup to do so with ALMA, combining observations of the peak and Rayleigh-Jeans tail of the dust emission., Comment: 14 pages main text, 6 figures + appendices; re-submitted to MNRAS after a positive referee report
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- 2024
11. ALESS-JWST: Joint (sub-)kiloparsec JWST and ALMA imaging of $z\sim3$ submillimeter galaxies reveals heavily obscured bulge formation events
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Hodge, Jacqueline A., da Cunha, Elisabete, Kendrew, Sarah, Li, Juno, Smail, Ian, Westoby, Bethany A., Nayak, Omnarayani, Swinbank, Mark, Chen, Chian-Chou, Walter, Fabian, van der Werf, Paul, Cracraft, Misty, Battisti, Andrew, Brandt, Willian N., Rivera, Gabriela Calistro, Chapman, Scott C., Cox, Pierre, Dannerbauer, Helmut, Decarli, Roberto, Castillo, Marta Frias, Greve, Thomas R., Knudsen, Kirsten K., Leslie, Sarah, Menten, Karl M., Rybak, Matus, Schinnerer, Eva, Wardlow, Julie L., and Weiss, Axel
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Astrophysics - Astrophysics of Galaxies - Abstract
We present JWST NIRCam imaging targeting 13 $z\sim3$ infrared-luminous ($L_{\rm IR}\sim5\times10^{12}L_{\odot}$) galaxies from the ALESS survey with uniquely deep, high-resolution (0.08$''$$-$0.16$''$) ALMA 870$\mu$m imaging. The 2.0$-$4.4$\mu$m (observed frame) NIRCam imaging reveals the rest-frame near-infrared stellar emission in these submillimeter-selected galaxies (SMGs) at the same (sub-)kpc resolution as the 870$\mu$m dust continuum. The newly revealed stellar morphologies show striking similarities with the dust continuum morphologies at 870$\mu$m, with the centers and position angles agreeing for most sources, clearly illustrating that the spatial offsets reported previously between the 870$\mu$m and HST morphologies were due to strong differential dust obscuration. The F444W sizes are 78$\pm$21% larger than those measured at 870$\mu$m, in contrast to recent results from hydrodynamical simulations that predict larger 870$\mu$m sizes. We report evidence for significant dust obscuration in F444W for the highest-redshift sources, emphasizing the importance of longer-wavelength MIRI imaging. The majority of the sources show evidence that they are undergoing mergers/interactions, including tidal tails/plumes -- some of which are also detected at 870$\mu$m. We find a clear correlation between NIRCam colors and 870$\mu$m surface brightness on $\sim$1 kpc scales, indicating that the galaxies are primarily red due to dust -- not stellar age -- and we show that the dust structure on $\sim$kpc-scales is broadly similar to that in nearby galaxies. Finally, we find no strong stellar bars in the rest-frame near-infrared, suggesting the extended bar-like features seen at 870$\mu$m are highly obscured and/or gas-dominated structures that are likely early precursors to significant bulge growth., Comment: 26 pages, 10 figures. Submitted to ApJ. Comments welcome
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- 2024
12. A Perspective on Foundation Models for the Electric Power Grid
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Hamann, Hendrik F., Brunschwiler, Thomas, Gjorgiev, Blazhe, Martins, Leonardo S. A., Puech, Alban, Varbella, Anna, Weiss, Jonas, Bernabe-Moreno, Juan, Massé, Alexandre Blondin, Choi, Seong, Foster, Ian, Hodge, Bri-Mathias, Jain, Rishabh, Kim, Kibaek, Mai, Vincent, Mirallès, François, De Montigny, Martin, Ramos-Leaños, Octavio, Suprême, Hussein, Xie, Le, Youssef, El-Nasser S., Zinflou, Arnaud, Belvi, Alexander J., Bessa, Ricardo J., Bhattari, Bishnu Prasad, Schmude, Johannes, and Sobolevsky, Stanislav
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence ,Computer Science - Computational Engineering, Finance, and Science ,Electrical Engineering and Systems Science - Systems and Control - Abstract
Foundation models (FMs) currently dominate news headlines. They employ advanced deep learning architectures to extract structural information autonomously from vast datasets through self-supervision. The resulting rich representations of complex systems and dynamics can be applied to many downstream applications. Therefore, FMs can find uses in electric power grids, challenged by the energy transition and climate change. In this paper, we call for the development of, and state why we believe in, the potential of FMs for electric grids. We highlight their strengths and weaknesses amidst the challenges of a changing grid. We argue that an FM learning from diverse grid data and topologies could unlock transformative capabilities, pioneering a new approach in leveraging AI to redefine how we manage complexity and uncertainty in the electric grid. Finally, we discuss a power grid FM concept, namely GridFM, based on graph neural networks and show how different downstream tasks benefit., Comment: Lead contact: H.F.H.; Major equal contributors: H.F.H., T.B., B.G., L.S.A.M., A.P., A.V., J.W.; Significant equal contributors: J.B., A.B.M., S.C., I.F., B.H., R.J., K.K., V.M., F.M., M.D.M., O.R., H.S., L.X., E.S.Y., A.Z.; Other equal contributors: A.J.B., R.J.B., B.P.B., J.S., S.S
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- 2024
13. Semi-Supervised Multi-Task Learning Based Framework for Power System Security Assessment
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Za'ter, Muhy Eddin, Sajadi, Amirhossein, and Hodge, Bri-Mathias
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Computer Science - Machine Learning ,Electrical Engineering and Systems Science - Systems and Control - Abstract
This paper develops a novel machine learning-based framework using Semi-Supervised Multi-Task Learning (SS-MTL) for power system dynamic security assessment that is accurate, reliable, and aware of topological changes. The learning algorithm underlying the proposed framework integrates conditional masked encoders and employs multi-task learning for classification-aware feature representation, which improves the accuracy and scalability to larger systems. Additionally, this framework incorporates a confidence measure for its predictions, enhancing its reliability and interpretability. A topological similarity index has also been incorporated to add topological awareness to the framework. Various experiments on the IEEE 68-bus system were conducted to validate the proposed method, employing two distinct database generation techniques to generate the required data to train the machine learning algorithm. The results demonstrate that our algorithm outperforms existing state-of-the-art machine learning based techniques for security assessment in terms of accuracy and robustness. Finally, our work underscores the value of employing auto-encoders for security assessment, highlighting improvements in accuracy, reliability, and robustness. All datasets and codes used have been made publicly available to ensure reproducibility and transparency.
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- 2024
14. A photo-$z$ cautionary tale: Redshift confirmation of COSBO-7 at $z=2.625$
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Jin, Shuowen, Sillassen, Nikolaj B., Hodge, Jacqueline, Magdis, Georgios E., Casey, Caitlin, Rizzo, Francesca, Koekemoer, Anton M., Valentino, Francesco, Kokorev, Vasily, Magnelli, Benjamin, Gobat, Raphael, Gillman, Steven, Franco, Maximilien, Faisst, Andreas, Kartaltepe, Jeyhan, Schinnerer, Eva, Toft, Sune, Algera, Hiddo S. B., Harish, Santosh, Lee, Minju, Liu, Daizhong, Shuntov, Marko, Talia, Margherita, and Vijayan, Aswin
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Photometric redshifts are widely used in studies of dusty star-forming galaxies (DSFGs), but catastrophic photo-$z$ failure can undermine all redshift-dependent results. Here we report the spectroscopic redshift confirmation of COSBO-7, a strongly lensed DSFG in the COSMOS-PRIMER field. Recently, using 10 bands of JWST NIRCam and MIRI imaging data on COSBO-7, Ling et al. (2024) reported a photometric redshift solution of $z\gtrsim7.0$, favored by four independent spectral energy distribution (SED) fitting codes, and therefore providing an appealing candidate of the most distant massive DSFG. This photo-$z$ solution was also supported by a single line detection in ALMA Band 3 consistent with CO(7-6) at $z=7.46$. However, our new ALMA observations robustly detect two lines in Band 6 identified as CO(7-6) and [CI](2-1) at $z_{\rm spec}=2.625$, and thus the Band 3 line as CO(3-2). The three robust line detections decidedly place COSBO-7 at $z=2.625$, refuting the photo-$z$ solution. We derive physical parameters by fitting NIR-to-mm photometry and lens modeling, revealing that COSBO-7 is a main-sequence galaxy. We examine possible reasons for this photo-$z$ failure and attribute it to (1) the likely underestimation of photometric uncertainty at 0.9$\mu$m, and (2) the lack of photometry at wavelengths beyond 20$\mu$m. Notably, we recover a bona-fide $z_{\rm phot}\sim 2.3$ by including the existing MIPS $24\mu$m photometry, demonstrating the critical importance of mid-infrared data for photo-$z$ robustness. This work highlights a common challenge in modeling SEDs of DSFGs, cautioning against the reliability of photometric redshifts, as well as pseudo-spectroscopic redshifts based on single line detection., Comment: Submitted to A&A Letter
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- 2024
15. Parasympathetic Regulation and Support from Family and Friends Predict Prosocial Development in U.S. Mexican-Origin Adolescents
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Paul D. Hastings, Jonas G. Miller, David G. Weissman, Ryan T. Hodge, Richard W. Robins, Gustavo Carlo, and Amanda E. Guyer
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Both parasympathetic nervous system regulation and receipt of social support from close relationships contribute to prosocial development, although few studies have examined their combined influences in adolescence and particularly within racially and ethnically minoritized populations. In this longitudinal study of 229 U.S. Mexican-origin adolescents (48% female-identifying), youths reported on receipt of social support from family and friends from 10 to 16 years, had their baseline respiratory sinus arrhythmia (RSA) measured at 17 years, reported their prosocial behavior and completed the Mind in the Eyes test to assess cognitive empathy at 17 and 19 years, and reported their prosocial civic behavior (i.e., community activity) at 19 years. Family social support predicted prosocial behavior at 17 years, and friend social support predicted prosocial civic behavior at 19 years. Compared to youths with lower or higher baseline RSA, youths with moderate RSA reported more prosocial civic behavior, had greater cognitive empathy, and tended to report more general prosocial behavior at 19 years. The quadratic association between baseline RSA and cognitive empathy was stronger for youths with greater family social support. These findings are the first to extend the evidence that moderate baseline parasympathetic nervous system activity supports prosocial development into late adolescence and with the U.S. Mexican-origin community, and these findings address calls for more integrative biopsychosocial studies of prosociality.
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- 2024
- Full Text
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16. An intronic copy number variation in Syntaxin 17 determines speed of greying and melanoma incidence in Grey horses.
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Rubin, Carl-Johan, Hodge, McKaela, Naboulsi, Rakan, Beckman, Madeleine, Bellone, Rebecca, Kallenberg, Angelica, JUsrey, Stephanie, Ohmura, Hajime, Seki, Kazuhiro, Furukawa, Risako, Ohnuma, Aoi, Davis, Brian, Tozaki, Teruaki, Lindgren, Gabriella, and Andersson, Leif
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Horses ,Animals ,DNA Copy Number Variations ,Qa-SNARE Proteins ,Melanoma ,Introns ,Hair Color ,Alleles ,Pedigree ,Male ,Female ,Phenotype ,Incidence ,Horse Diseases ,Skin Pigmentation - Abstract
The Greying with age phenotype in horses involves loss of hair pigmentation whereas skin pigmentation is not reduced, and a predisposition to melanoma. The causal mutation was initially reported as a duplication of a 4.6 kb intronic sequence in Syntaxin 17. The speed of greying varies considerably among Grey horses. Here we demonstrate the presence of two different Grey alleles, G2 carrying two tandem copies of the duplicated sequence and G3 carrying three. The latter is by far the most common allele, probably due to strong selection for the striking white phenotype. Our results reveal a remarkable dosage effect where the G3 allele is associated with fast greying and high incidence of melanoma whereas G2 is associated with slow greying and low incidence of melanoma. The copy number expansion transforms a weak enhancer to a strong melanocyte-specific enhancer that underlies hair greying (G2 and G3) and a drastically elevated risk of melanoma (G3 only). Our direct pedigree-based observation of the origin of a G2 allele from a G3 allele by copy number contraction demonstrates the dynamic evolution of this locus and provides the ultimate evidence for causality of the copy number variation of the 4.6 kb intronic sequence.
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- 2024
17. Patient experiences switching from in‐clinic to self‐administration of injectable contraception in two Western US states
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Newmark, Rebecca L, Hodge, Caroline C, Shih, Grace, and Karlin, Jennifer
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Human Society ,Public Health ,Health Sciences ,Demography ,Coronaviruses ,Clinical Research ,Contraception/Reproduction ,Infectious Diseases ,Behavioral and Social Science ,Good Health and Well Being ,contraception ,hormonal implants/injectables ,qualitative research methods ,quality of care ,united states ,Public health - Abstract
ObjectiveWe describe the experiences and preferences of women who switched from clinic-administered intramuscular depot medroxyprogesterone acetate (DMPA-IM) to self-administered subcutaneous DMPA (DMPA-SC) in the context of the COVID-19 pandemic.MethodsWe conducted interviews with women in California and Washington about their experiences with self-administered DMPA-SC. We interviewed women after their first or second self-administered DMPA-SC injection and conducted follow-up interviews after their third or fourth injection. We performed both thematic and descriptive content analyses.ResultsWe completed 29 interviews with 15 women. Most participants (n = 10) were between the ages of 20 and 39 and the majority (n = 12) used DMPA primarily for contraception. Most (n = 13) described self-administered DMPA-SC as "very easy" or "somewhat easy" to use and reported greater convenience, decreased pain, fewer logistical and financial challenges, increased privacy, and improved comfort with injection compared to DMPA-IM. Participants identified difficulties obtaining DMPA-SC from pharmacies and safe needle disposal as barriers. Most (n = 13) would recommend DMPA-SC to a friend and desired to continue self-administration beyond the COVID-19 pandemic. Participants recommended counseling all patients about this option alongside other contraceptive methods, and offering clinician supervision, if desired.ConclusionWomen who switched from in-clinic DMPA-IM to self-administered DMPA-SC during the COVID-19 pandemic preferred the latter and intended to continue self-administration. Self-administration of DMPA-SC should be routinely offered and easily accessible to patients.
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- 2024
18. A Heavily Scattered Fast Radio Burst Is Viewed Through Multiple Galaxy Halos
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Faber, Jakob T., Ravi, Vikram, Ocker, Stella Koch, Sherman, Myles B., Sharma, Kritti, Connor, Liam, Law, Casey, Kosogorov, Nikita, Hallinan, Gregg, Harnach, Charlie, Hellbourg, Greg, Hobbs, Rick, Hodge, David, Hodges, Mark, Lamb, James W., Rasmussen, Paul, Somalwar, Jean J., Weinreb, Sander, and Woody, David P.
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Astrophysics of Galaxies - Abstract
We present a multi-wavelength study of the apparently non-repeating, heavily scattered fast radio burst, FRB 20221219A, detected by the Deep Synoptic Array 110 (DSA-110). The burst exhibits a moderate dispersion measure (DM) of $706.7^{+0.6}_{-0.6}$ $\mathrm{pc}~\mathrm{cm}^{-3}$ and an unusually high scattering timescale of $\tau_{\mathrm{obs}} = 19.2_{-2.7}^{+2.7}$ ms at 1.4 GHz. We associate the FRB with a Milky Way-like host galaxy at $z_{\mathrm{host}} = 0.554$ of stellar mass $\mathrm{log}_{10}(M_{\star, \mathrm{host}}) = 10.20^{+0.04}_{-0.03} ~M_\odot$. We identify two intervening galaxy halos at redshifts $z_{\mathrm{igh1}} = 0.492$ and $z_{\mathrm{igh2}} = 0.438$, with low impact parameters, $b_{\mathrm{igh1}} = 43.0_{-11.3}^{+11.3}$ kpc and $b_{\mathrm{igh2}} = 36.1_{-11.3}^{+11.3}$ kpc, and intermediate stellar masses, $\mathrm{log}_{10}(M_{\star, \mathrm{igh1}}) = 10.01^{+0.02}_{-0.02} ~M_\odot$ and $\mathrm{log}_{10}(M_{\star, \mathrm{igh2}}) = 10.60^{+0.02}_{-0.02} ~M_\odot$. The presence of two such galaxies suggests that the sightline is significantly overcrowded compared to the median sightline to this redshift, as inferred from the halo mass function. We perform a detailed analysis of the sightline toward FRB 20221219A, constructing both DM and scattering budgets. Our results suggest that, unlike most well-localized sources, the host galaxy does not dominate the observed scattering. Instead, we posit that an intersection with a single partially ionized cloudlet in the circumgalactic medium of an intervening galaxy could account for the substantial scattering in FRB 20221219A and remain in agreement with typical electron densities inferred for extra-planar dense cloud-like structures in the Galactic and extragalactic halos (e.g., high-velocity clouds)., Comment: 18 pages, 6 figures, submitted to ApJ, comments appreciated
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- 2024
19. Constraining possible $\gamma$-ray burst emission from GW230529 using Swift-BAT and Fermi-GBM
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Ronchini, Samuele, Bala, Suman, Wood, Joshua, Delaunay, James, Dichiara, Simone, Kennea, Jamie A., Parsotan, Tyler, Raman, Gayathri, Tohuvavohu, Aaron, Adhikari, Naresh, Bhat, Narayana P., Biscoveanu, Sylvia, Bissaldi, Elisabetta, Burns, Eric, Campana, Sergio, Chandra, Koustav, Cleveland, William H., Dalessi, Sarah, De Pasquale, Massimiliano, García-Bellido, Juan, Gasbarra, Claudio, Giles, Misty M., Gupta, Ish, Hartmann, Dieter, Hristov, Boyan A., Hui, Michelle C., Kashyap, Rahul, Kocevski, Daniel, Mailyan, Bagrat, Malacaria, Christian, Nakano, Hiroyuki, Principe, Giacomo, Roberts, Oliver J., Sathyaprakash, Bangalore, Shao, Lijing, Troja, Eleonora, Veres, Péter, and Wilson-Hodge, Colleen A.
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Astrophysics - High Energy Astrophysical Phenomena ,General Relativity and Quantum Cosmology - Abstract
GW230529 is the first compact binary coalescence detected by the LIGO-Virgo-KAGRA collaboration with at least one component mass confidently in the lower mass-gap, corresponding to the range 3-5$M_{\odot}$. If interpreted as a neutron star-black hole merger, this event has the most symmetric mass ratio detected so far and therefore has a relatively high probability of producing electromagnetic (EM) emission. However, no EM counterpart has been reported. At the merger time $t_0$, Swift-BAT and Fermi-GBM together covered 100$\%$ of the sky. Performing a targeted search in a time window $[t_0-20 \text{s},t_0+20 \text{s}]$, we report no detection by the Swift-BAT and the Fermi-GBM instruments. Combining the position-dependent $\gamma-$ray flux upper limits and the gravitational-wave posterior distribution of luminosity distance, sky localization and inclination angle of the binary, we derive constraints on the characteristic luminosity and structure of the jet possibly launched during the merger. Assuming a top-hat jet structure, we exclude at 90$\%$ credibility the presence of a jet which has at the same time an on-axis isotropic luminosity $\gtrsim 10^{48}$ erg s$^{-1}$, in the bolometric band 1 keV-10 MeV, and a jet opening angle $\gtrsim 15$ deg. Similar constraints are derived testing other assumptions about the jet structure profile. Excluding GRB 170817A, the luminosity upper limits derived here are below the luminosity of any GRB observed so far., Comment: 18 pages, 1 table, 11 figures
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- 2024
20. Studying geometry of the ultraluminous X-ray pulsar Swift J0243.6+6124 using X-ray and optical polarimetry
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Poutanen, Juri, Tsygankov, Sergey S., Doroshenko, Victor, Forsblom, Sofia V., Jenke, Peter, Kaaret, Philip, Berdyugin, Andrei V., Blinov, Dmitry, Kravtsov, Vadim, Liodakis, Ioannis, Tzouvanou, Anastasia, Di Marco, Alessandro, Heyl, Jeremy, La Monaca, Fabio, Mushtukov, Alexander A., Pavlov, George G., Salganik, Alexander, Veledina, Alexandra, Weisskopf, Martin C., Zane, Silvia, Loktev, Vladislav, Suleimanov, Valery F., Wilson-Hodge, Colleen, Berdyugina, Svetlana V., Kagitani, Masato, Piirola, Vilppu, Sakanoi, Takeshi, Agudo, Ivan, Antonelli, Lucio A., Bachetti, Matteo, Baldini, Luca, Baumgartner, Wayne H., Bellazzini, Ronaldo, Bianchi, Stefano, Bongiorno, Stephen D., Bonino, Raffaella, Brez, Alessandro, Bucciantini, Niccolo, Capitanio, Fiamma, Castellano, Simone, Cavazzuti, Elisabetta, Chen, Chien-Ting, Ciprini, Stefano, Costa, Enrico, De Rosa, Alessandra, Del Monte, Ettore, Di Gesu, Laura, Di Lalla, Niccolo, Donnarumma, Immacolata, Dovciak, Michal, Ehlert, Steven R., Enoto, Teruaki, Evangelista, Yuri, Fabiani, Sergio, Ferrazzoli, Riccardo, Garcia, Javier A., Gunji, Shuichi, Hayashida, Kiyoshi, Iwakiri, Wataru, Jorstad, Svetlana G., Karas, Vladimir, Kislat, Fabian, Kitaguchi, Takao, Kolodziejczak, Jeffery J., Latronico, Luca, Maldera, Simone, Manfreda, Alberto, Marin, Frederic, Marinucci, Andrea, Marscher, Alan P., Marshall, Herman L., Massaro, Francesco, Matt, Giorgio, Mitsuishi, Ikuyuki, Mizuno, Tsunefumi, Muleri, Fabio, Negro, Michela, Ng, Chi-Yung, O'Dell, Stephen L., Omodei, Nicola, Oppedisano, Chiara, Papitto, Alessandro, Peirson, Abel L., Perri, Matteo, Pesce-Rollins, Melissa, Petrucci, Pierre-Olivier, Pilia, Maura, Possenti, Andrea, Puccetti, Simonetta, Ramsey, Brian D., Rankin, John, Ratheesh, Ajay, Roberts, Oliver J., Romani, Roger W., Sgro, Carmelo, Slane, Patrick, Soffitta, Paolo, Spandre, Gloria, Swartz, Douglas A., Tamagawa, Toru, Tavecchio, Fabrizio, Taverna, Roberto, Tawara, Yuzuru, Tennant, Allyn F., Thomas, Nicholas E., Tombesi, Francesco, Trois, Alessio, Turolla, Roberto, Vink, Jacco, Wu, Kinwah, and Xie, Fei
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Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Discovery of pulsations from a number of ultra-luminous X-ray (ULX) sources proved that accretion onto neutron stars can produce luminosities exceeding the Eddington limit by a couple of orders of magnitude. The conditions necessary to achieve such high luminosities as well as the exact geometry of the accretion flow in the neutron star vicinity are, however, a matter of debate. The pulse phase-resolved polarization measurements that became possible with the launch of the IXPE can be used to determine the pulsar geometry and its orientation relative to the orbital plane. They provide an avenue to test different theoretical models of ULX pulsars. In this paper we present the results of three IXPE observations of the first Galactic ULX pulsar Swift J0243.6+6124 during its 2023 outburst. We find strong variations of the polarization characteristics with the pulsar phase. The average polarization degree increases from about 5% to 15% as the flux dropped by a factor of three in the course of the outburst. The polarization angle (PA) as function of the pulsar phase shows two peaks in the first two observations, but changes to a characteristic sawtooth pattern in the remaining data set. This is not consistent with a simple rotating vector model. Assuming the existence of an additional constant polarized component, we were able to fit the three observations with a common rotating vector model and obtain constraints on the pulsar geometry. In particular, we find the pulsar angular momentum inclination with respect to the line-of-sight of 15-40 deg, the magnetic obliquity of 60-80 deg, and the pulsar spin position angle of -50 deg, which differs from the constant component PA of about 10 deg. Combining these X-ray measurements with the optical PA, we find evidence for a 30 deg misalignment between the pulsar spin and the binary orbital axis., Comment: 13 pages, 10 figures, submitted to A&A
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- 2024
21. Acceleration of Power System Dynamic Simulations using a Deep Equilibrium Layer and Neural ODE Surrogate
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Bossart, Matthew, Lara, Jose Daniel, Roberts, Ciaran, Henriquez-Auba, Rodrigo, Callaway, Duncan, and Hodge, Bri-Mathias
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Electrical Engineering and Systems Science - Systems and Control - Abstract
The dominant paradigm for power system dynamic simulation is to build system-level simulations by combining physics-based models of individual components. The sheer size of the system along with the rapid integration of inverter-based resources exacerbates the computational burden of running time domain simulations. In this paper, we propose a data-driven surrogate model based on implicit machine learning -- specifically deep equilibrium layers and neural ordinary differential equations -- to learn a reduced order model of a portion of the full underlying system. The data-driven surrogate achieves similar accuracy and reduction in simulation time compared to a physics-based surrogate, without the constraint of requiring detailed knowledge of the underlying dynamic models. This work also establishes key requirements needed to integrate the surrogate into existing simulation workflows; the proposed surrogate is initialized to a steady state operating point that matches the power flow solution by design., Comment: This work has been submitted to the IEEE Transactions on Energy Conversion for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible
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- 2024
22. REBELS-25: Discovery of a dynamically cold disc galaxy at z = 7.31
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Rowland, Lucie E., Hodge, Jacqueline, Bouwens, Rychard, Piña, Pavel Mancera, Hygate, Alexander, Algera, Hiddo, Aravena, Manuel, Bowler, Rebecca, da Cunha, Elisabete, Dayal, Pratika, Ferrara, Andrea, Herard-Demanche, Thomas, Inami, Hanae, van Leeuwen, Ivana, de Looze, Ilse, Oesch, Pascal, Pallottini, Andrea, Phillips, Siân, Rybak, Matus, Schouws, Sander, Smit, Renske, Sommovigo, Laura, Stefanon, Mauro, and van der Werf, Paul
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Astrophysics - Astrophysics of Galaxies - Abstract
We present high resolution ($\sim0.14$" = 710 pc) ALMA [CII] 158$\mu$m and dust continuum follow-up observations of REBELS-25, a [CII]-luminous ($L_{\mathrm{[CII]}}=(1.7\pm0.2)\times 10^9 \mathrm{L_{\odot}}$) galaxy at redshift $z=7.3065\pm0.0001$. These high resolution, high signal-to-noise observations allow us to study the sub-kpc morphology and kinematics of this massive ($M_* = 8^{+4}_{-2} \times 10^9 \mathrm{M_{\odot}}$) star-forming (SFR$_{\mathrm{UV+IR}} = 199^{+101}_{-63} \mathrm{M_{\odot}} \mathrm{yr}^{-1}$) galaxy in the Epoch of Reionisation. By modelling the kinematics with $^{\mathrm{3D}}$BAROLO, we find it has a low velocity dispersion ($\bar{\sigma} = 33 \pm 9$ km s$^{-1}$) and a high ratio of ordered-to-random motion ($V_{\mathrm{rot, ~max}}/\bar{\sigma} = 11 ^{+8}_{-4}$), indicating that REBELS-25 is a dynamically cold disc. Additionally, we find that the [CII] distribution is well fit by a near-exponential disc model, with a S\'ersic index, $n$, of $1.3 \pm 0.2$, and we see tentative evidence of more complex non-axisymmetric structures suggestive of a bar in the [CII] and dust continuum emission. By comparing to other high spatial resolution cold gas kinematic studies, we find that dynamically cold discs seem to be more common in the high redshift Universe than expected based on prevailing galaxy formation theories, which typically predict more turbulent and dispersion-dominated galaxies in the early Universe as an outcome of merger activity, gas accretion and more intense feedback. This higher degree of rotational support seems instead to be consistent with recent cosmological simulations that have highlighted the contrast between cold and warm ionised gas tracers, particularly for massive galaxies. We therefore show that dynamically settled disc galaxies can form as early as 700 Myr after the Big Bang., Comment: Submitted to MNRAS
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- 2024
23. Future Perspectives for Gamma-ray Burst Detection from Space
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Bozzo, Enrico, Amati, Lorenzo, Baumgartner, Wayne, Chang, Tzu-Ching, Cordier, Bertrand, De Angelis, Nicolas, Doi, Akihiro, Feroci, Marco, Froning, Cynthia, Gaskin, Jessica, Goldstein, Adam, Götz, Diego, Grove, Jon E., Guiriec, Sylvain, Hernanz, Margarita, Hui, C. Michelle, Jenke, Peter, Kocevski, Daniel, Kole, Merlin, Kouveliotou, Chryssa, Maccarone, Thomas, McConnell, Mark L., Matsuhara, Hideo, O'Brien, Paul, Produit, Nicolas, Ray, Paul S., Roming, Peter, Santangelo, Andrea, Seiffert, Michael, Sun, Hui, van der Horst, Alexander, Veres, Peter, Wei, Jianyan, White, Nicholas, Wilson-Hodge, Colleen, Yonetoku, Daisuke, Yuan, Weimin, and Zhang, Shuang-Nan
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Since their first discovery in the late 1960s, Gamma-ray bursts have attracted an exponentially growing interest from the international community due to their central role in the most highly debated open questions of the modern research of astronomy, astrophysics, cosmology, and fundamental physics. These range from the intimate nuclear composition of high density material within the core of ultra-dense neuron stars, to stellar evolution via the collapse of massive stars, the production and propagation of gravitational waves, as well as the exploration of the early Universe by unveiling first stars and galaxies (assessing also their evolution and cosmic re-ionization). GRBs have stimulated in the past $\sim$50 years the development of cutting-edge technological instruments for observations of high energy celestial sources from space, leading to the launch and successful operations of many different scientific missions (several of them still in data taking mode nowadays). In this review, we provide a brief description of the GRB-dedicated missions from space being designed and developed for the future. The list of these projects, not meant to be exhaustive, shall serve as a reference to interested readers to understand what is likely to come next to lead the further development of GRB research and associated phenomenology., Comment: Accepted for publication on Universe. Invited review, contribution to the Universe Special Issue "Recent Advances in Gamma Ray Astrophysics and Future Perspectives", P. Romano eds. (https://www.mdpi.com/journal/universe/special_issues/7299902Z97)
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- 2024
24. Synchronization in Modern Heterogeneous Power Networks with Inverter-Based Resources
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Walth, Mark, Sajadi, Amir, and Hodge, Bri-Mathias
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Electrical Engineering and Systems Science - Systems and Control ,Mathematics - Dynamical Systems - Abstract
Synchronized operation of generators in a power network is paramount to the stability and reliability of energy delivery. In this paper, we address the synchronization problem in a heterogeneous power grid, consisting of both synchronous generators and inverter-based generators, and derive the necessary and sufficient condition guaranteeing the existence of a unique locally stable synchronized mode. Further, our results have implications for utilizing grid-following inverters versus grid-forming inverters in order to enhance network stability. This work is of particular importance as power grids around the world are undergoing a transition from being predominantly composed of synchronous generators towards a grid consisting of a preponderance of inverter based generators., Comment: 14 pages, 6 figures, 2 tables. Submitted to "Automatica"
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- 2024
25. A Comparative Study of the Ground State Transitions of CO and [C I] as Molecular Gas Tracers at High Redshift
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Castillo, Marta Frias, Rybak, Matus, Hodge, Jacqueline A., Van der Werk, Paul, Smail, Ian, Butterworth, Joshua, Jansen, Jasper, Topkaras, Theodoros, Chen, Chian-Chou, Chapman, Scott C., Weiss, Axel, Algera, Hiddo, Birkin, Jack E., da Cunha, Elisabete, Chen, Jianhang, Dannerbauer, Helmut, Jiménez-Andrade, E. F., Ikarashi, Soh, Liao, Cheng-Lin, Murphy, Eric J., Swinbank, A. M., Walter, Fabian, Rivera, Gabriela Calistro, Ivison, R. J., and Lagos, Claudia del P.
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Astrophysics - Astrophysics of Galaxies - Abstract
The CO(1--0) and [\ion{C}{1}](1--0) emission lines are well-established tracers of cold molecular gas mass in local galaxies. At high redshift, where the interstellar medium (ISM) is likely to be denser, there have been limited direct comparisons of both ground state transitions. Here we present a study of CO(1--0) and [\ion{C}{1}](1--0) emission in a sample of 20 unlensed dusty, star-forming galaxies at $z=2-5$. The CO(1--0)/[\ion{C}{1}](1--0) ratio is constant up to at least $z=5$, supporting the use of [CI](1-0) as a gas mass tracer. PDR modelling of the available data indicates a median H$_2$ density of log$(n~[$cm$^{-3}])=4.7\pm0.2$, and UV radiation field log$(G_{\mathrm{UV}} [G$_0$])=3.2\pm0.2$. We use the CO(1--0), [\ion{C}{1}](1--0) and 3mm dust continuum measurements to cross--calibrate the respective gas mass conversion factors, finding no dependence of these factors on either redshift or infrared luminosity. Assuming a variable CO conversion factor then implies [\ion{C}{1}] and dust conversion factors that differ from canonically assumed values but are consistent with the solar/super-solar metallicities expected for our sources. Radiative transfer modelling shows that the warmer CMB at high redshift can significantly affect the [\ion{C}{1}] as well as CO emission, which can change the derived molecular gas masses by up to 70\% for the coldest kinetic gas temperatures expected. Nevertheless, we show that the magnitude of the effect on the ratio of the tracers is within the known scatter of the $L'_\mathrm{CO}-L'_\mathrm{[CI]}$ relation. Further determining the absolute decrease of individual line intensities will require well-sampled spectral line energy distributions (SLEDs) to model the gas excitation conditions in more detail.
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- 2024
26. Lamb mortality and clostridial disease
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Bingham, C. M. and Hodge, A.
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- 2022
27. Onboarding and Education Design Principles for Learning and Employment Records
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Digital Promise, Malliron Hodge, Zohal Shah, Marika Patterson, and Christina Luke Luna
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This report represents another installment in our Learning and Employment Records (LERs) series, where we explored the unique challenges and opportunities that learners encounter when familiarizing themselves with LER technology. As the paradigm shifts towards skills-based hiring and career advancement gains momentum, it becomes imperative for technologies like LERs to provide a transparent, user-friendly, and accessible onboarding experience. Digital Promise collaborated closely with historically and systematically excluded (HSE) adult learners and workers, including those facing economic hardship and multilingual learners, to establish a set of onboarding design principles. These principles are designed to ensure that LERs are crafted in ways that actively engage a diverse range of users.
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- 2023
28. Empowering Medical Educators: A UTAUT Analysis of Technology Adoption in Inquiry-Based Learning
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Max C. Anderson, Cindy S. York, Angie Hodge-Zickerman, Yoon Soo Park, and Jason Rhode
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This non-experimental quantitative study investigated medical school faculty members' behavioral intention to use and actual usage behavior of technology in inquiry-based learning activities in medical schools in the United States by applying the unified theory of acceptance and use of technology (UTAUT). In medical education, situational problems for students to solve typically incorporate instructive clinical cases to guide problem-solving and prepare them for their professional lives as clinicians. Technology-infused inquiry-based learning pedagogy can require significant paradigm shifts for both students and instructors. It can impact the level of responsibility students take upon themselves for their own learning, and use of a pedagogy instructors may find unfamiliar, to deliver content. Major findings demonstrated performance expectancy, effort expectancy, and social influence had a significant relationship with behavioral intention to use technology for teaching medical education inquiry-based activities. Gender and voluntariness of use were both found to have significant effects on the relationship between performance expectancy and behavioral intention to use technology. The results of this study can aid stakeholders in providing support mechanisms for faculty to adopt technology for teaching and learning. This is possibly the first of its kind on the application of this theoretical model to address medical educators' behavioral intention to use and actual usage behavior of educational technologies for the delivery of inquiry-based learning activities.
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- 2024
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29. Teachers' Beliefs about Technology Integration in Ghana: A Qualitative Study of Teachers', Headteachers' and Education Officials' Perceptions
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Emmanuel Ayisi Abedi, Sarah Prestridge, and Steven Hodge
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With increasing policy interest in improving educational outcomes, technology integration has become a requirement in Ghana's education system, albeit with minimal impact on student learning. Several studies focus on identifying barriers to effective integration but pay scant consideration to the deeper reasons why teachers use technology. This qualitative study aimed to explore the underlying beliefs that shape teachers' decision-making and thinking regarding technology integration. The study used open-ended questions and interviews with five education officials, twenty teachers, and five headteachers, and an 'ICT Pedagogical Beliefs Classification Framework' as a lens for interpreting and categorising teacher beliefs. Thematic analysis of findings revealed four main beliefs: productivity tools for teaching and lesson preparation; developing students' ICT skills; meeting curriculum expectations, and engaging students in authentic teaching. Evidently, teachers are enthusiastic about using technology, but their beliefs indicate that they view technology primarily as a tool for productivity to supplement existing teaching practices, which they value. Findings indicate that most teachers espouse teacher-centred ICT beliefs, implying the need for transformative professional development that enables change in teachers' beliefs to embrace the view of technology as a pedagogical tool that can facilitate constructive pedagogy and deep student learning.
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- 2024
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30. A Plain Man’s Guide to Roman Plumbing
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Hodge, A. Trevor
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- 2018
31. Ancient Science and Technology
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Hodge, A. Trevor
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- 2018
32. Massalia - The Truth!
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Hodge, A. Trevor
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- 2018
33. Radiation and Heat Transport in Divergent Shock-Bubble Interactions
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Kurzer-Ogul, Kelin, Haines, Brian M., Montgomery, David S., Pandolfi, Silvia, Sauppe, Joshua P., Leong, Andrew F. T., Hodge, Daniel, Kozlowski, Pawel M., Marchesini, Stefano, Cunningham, Eric, Galtier, Eric, Khaghani, Dimitri, Lee, Hae Ja, Nagler, Bob, Sandberg, Richard L., Gleason, Arianna E., Aluie, Hussein, and Shang, Jessica K.
- Subjects
Physics - Plasma Physics - Abstract
Shock-bubble interactions (SBI) are important across a wide range of physical systems. In inertial confinement fusion, interactions between laser-driven shocks and micro-voids in both ablators and foam targets generate instabilities that are a major obstacle in achieving ignition. Experiments imaging the collapse of such voids at high energy densities (HED) are constrained by spatial and temporal resolution, making simulations a vital tool in understanding these systems. In this study, we benchmark several radiation and thermal transport models in the xRAGE hydrodynamic code against experimental images of a collapsing mesoscale void during the passage of a 300 GPa shock. We also quantitatively examine the role of transport physics in the evolution of the SBI. This allows us to understand the dynamics of the interaction at timescales shorter than experimental imaging framerates. We find that all radiation models examined reproduce empirical shock velocities within experimental error. Radiation transport is found to reduce shock pressures by providing an additional energy pathway in the ablation region, but this effect is small ($\sim$1\% of total shock pressure). Employing a flux-limited Spitzer model for heat conduction, we find that flux limiters between 0.03 and 0.10 produce agreement with experimental velocities, suggesting that the system is well-within the Spitzer regime. Higher heat conduction is found to lower temperatures in the ablated plasma and to prevent secondary shocks at the ablation front, resulting in weaker primary shocks. Finally, we confirm that the SBI-driven instabilities observed in the HED regime are baroclinically driven, as in the low energy case., Comment: 14 pages, 12 figures
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- 2024
34. Characterizing Dynamic Majorana Hybridization for Universal Quantum Computing
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Hodge, Themba, Mascot, Eric, Crawford, Dan, and Rachel, Stephan
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Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Superconductivity ,Quantum Physics - Abstract
Qubits built out of Majorana zero modes have long been theorized as a potential pathway toward fault-tolerant topological quantum computation. Almost unavoidable in these processes is Majorana wavefunction overlap, known as hybridization, which arise throughout the process when Majorana modes get close to each other. This breaks the ground state degeneracy, leading to qubit errors in the braiding process. This work presents an accessible method to track transitions within the low-energy subspace and predict the output of braids with hybridized Majorana modes. As an application, we characterize Pauli qubit-errors, as demonstrated on an X-gate, critical for the successful operation of any quantum computer. Further, we perform numerical simulations to demonstrate how to utilize the hybridization to implement arbitrary rotations, along with a two-qubit controlled magic gate, thus providing a demonstration of universal quantum computing.
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- 2024
35. X-ray Microscopy and Talbot Imaging with the Matter in Extreme Conditions X-ray Imager at LCLS
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Galtier, Eric, Khaghani, Dimitri, Boiadjieva, Nina, Makita, Mikako, Gleason, Arianna E., Pandolfi, Silvia, Sakdinawat, Anne, Liu, Yanwei, Hodge, Daniel, Sandberg, Richard, Dyer, Gilliss, Heimann, Phil, Seiboth, Frank, Lee, Hae Ja, and Nagler, Bob
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Physics - Instrumentation and Detectors - Abstract
The last decade has shown the great potential that X-ray Free Electron Lasers (FEL) have to study High Energy Density matter. Experiments at FELs have made significant breakthroughs in Shock Physics and Dynamic Diffraction, Dense Plasma Physics and Warm Dense Matter Science, using techniques such as isochoric heating, inelastic scattering, small angle scattering and x-ray diffraction. In addition, and complementary to these techniques, the coherent properties of the FEL beam can be used to image HED samples with high fidelity. We present new imaging diagnostics and techniques developed at the Matter in Extreme Conditions (MEC) instrument at Linac Coherent Light Source (LCLS) over the last few years. We show result of a previously used Phase Contrast Imaging setup, where the X-ray beam propagates from the target to a camera some distance away revealing its phase, as well as a imaging approach where the target is re-imaged on the camera with 300nm resolution. Last, we show a new Talbot Imaging method allowing both x-ray phase and intensity measurements change introduced by a target with sub-micron resolution.
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- 2024
36. Detailed Report on the Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm
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Aguillard, D. P., Albahri, T., Allspach, D., Anisenkov, A., Badgley, K., Baeßler, S., Bailey, I., Bailey, L., Baranov, V. A., Barlas-Yucel, E., Barrett, T., Barzi, E., Bedeschi, F., Berz, M., Bhattacharya, M., Binney, H. P., Bloom, P., Bono, J., Bottalico, E., Bowcock, T., Braun, S., Bressler, M., Cantatore, G., Carey, R. M., Casey, B. C. K., Cauz, D., Chakraborty, R., Chapelain, A., Chappa, S., Charity, S., Chen, C., Cheng, M., Chislett, R., Chu, Z., Chupp, T. E., Claessens, C., Convery, M. E., Corrodi, S., Cotrozzi, L., Crnkovic, J. D., Dabagov, S., Debevec, P. T., Di Falco, S., Di Sciascio, G., Donati, S., Drendel, B., Driutti, A., Duginov, V. N., Eads, M., Edmonds, A., Esquivel, J., Farooq, M., Fatemi, R., Ferrari, C., Fertl, M., Fienberg, A. T., Fioretti, A., Flay, D., Foster, S. B., Friedsam, H., Froemming, N. S., Gabbanini, C., Gaines, I., Galati, M. D., Ganguly, S., Garcia, A., George, J., Gibbons, L. K., Gioiosa, A., Giovanetti, K. L., Girotti, P., Gohn, W., Goodenough, L., Gorringe, T., Grange, J., Grant, S., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Han, F., Hempstead, J., Hertzog, D. W., Hesketh, G., Hess, E., Hibbert, A., Hodge, Z., Hong, K. W., Hong, R., Hu, T., Hu, Y., Iacovacci, M., Incagli, M., Kammel, P., Kargiantoulakis, M., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Keshavarzi, A., Kessler, D. S., Khaw, K. S., Khechadoorian, Z., Khomutov, N. V., Kiburg, B., Kiburg, M., Kim, O., Kinnaird, N., Kraegeloh, E., Krylov, V. A., Kuchinskiy, N. A., Labe, K. R., LaBounty, J., Lancaster, M., Lee, S., Li, B., Li, D., Li, L., Logashenko, I., Campos, A. Lorente, Lu, Z., Lucà, A., Lukicov, G., Lusiani, A., Lyon, A. L., MacCoy, B., Madrak, R., Makino, K., Mastroianni, S., Miller, J. P., Miozzi, S., Mitra, B., Morgan, J. P., Morse, W. M., Mott, J., Nath, A., Ng, J. K., Nguyen, H., Oksuzian, Y., Omarov, Z., Osofsky, R., Park, S., Pauletta, G., Piacentino, G. M., Pilato, R. N., Pitts, K. T., Plaster, B., Počanić, D., Pohlman, N., Polly, C. C., Price, J., Quinn, B., Qureshi, M. U. H., Ramachandran, S., Ramberg, E., Reimann, R., Roberts, B. L., Rubin, D. L., Sakurai, M., Santi, L., Schlesier, C., Schreckenberger, A., Semertzidis, Y. K., Shemyakin, D., Sorbara, M., Stapleton, J., Still, D., Stöckinger, D., Stoughton, C., Stratakis, D., Swanson, H. E., Sweetmore, G., Sweigart, D. A., Syphers, M. J., Tarazona, D. A., Teubner, T., Tewsley-Booth, A. E., Tishchenko, V., Tran, N. H., Turner, W., Valetov, E., Vasilkova, D., Venanzoni, G., Volnykh, V. P., Walton, T., Weisskopf, A., Welty-Rieger, L., Winter, P., Wu, Y., Yu, B., Yucel, M., Zeng, Y., and Zhang, C.
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High Energy Physics - Experiment ,High Energy Physics - Phenomenology ,Nuclear Experiment - Abstract
We present details on a new measurement of the muon magnetic anomaly, $a_\mu = (g_\mu -2)/2$. The result is based on positive muon data taken at Fermilab's Muon Campus during the 2019 and 2020 accelerator runs. The measurement uses $3.1$ GeV$/c$ polarized muons stored in a $7.1$-m-radius storage ring with a $1.45$ T uniform magnetic field. The value of $ a_{\mu}$ is determined from the measured difference between the muon spin precession frequency and its cyclotron frequency. This difference is normalized to the strength of the magnetic field, measured using Nuclear Magnetic Resonance (NMR). The ratio is then corrected for small contributions from beam motion, beam dispersion, and transient magnetic fields. We measure $a_\mu = 116 592 057 (25) \times 10^{-11}$ (0.21 ppm). This is the world's most precise measurement of this quantity and represents a factor of $2.2$ improvement over our previous result based on the 2018 dataset. In combination, the two datasets yield $a_\mu(\text{FNAL}) = 116 592 055 (24) \times 10^{-11}$ (0.20 ppm). Combining this with the measurements from Brookhaven National Laboratory for both positive and negative muons, the new world average is $a_\mu$(exp) $ = 116 592 059 (22) \times 10^{-11}$ (0.19 ppm)., Comment: 48 pages, 29 figures; 4 pages of Supplement Material; version accepted for publication in Physical Review D
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- 2024
37. Optical and soft X-ray light-curve analysis during the 2022 eruption of U Scorpii: structural changes in the accretion disk
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Muraoka, Katsuki, Kojiguchi, Naoto, Ito, Junpei, Nogami, Daisaku, Kato, Taichi, Tampo, Yusuke, Taguchi, Kenta, Isogai, Keisuke, Arranz, Teofilo, Blackwell, John, Blane, David, Brincat, Stephen M., Coates, Graeme, Cooney, Walter, Dvorak, Shawn, Galdies, Charles, Glomski, Daniel, Hambsch, Franz-Josef, Harris, Barbara, Hodge, John, Hernández-Verdejo, Jose L., Iozzi, Marco, Itoh, Hiroshi, Kiyota, Seiichiro, Lee, Darrell, Larsson, Magnus, Lahtinen, Tapio, Myers, Gordon, Monard, Berto, Aimar, Mario Morales, Moriyama, Masayuki, Mizutani, Masanori, Nagai, Kazuo, AlQaissieh, Thabet, Gabuya, Aldrin B., Odeh, Mohammad, Perello, Carlos, Pearce, Andrew, Perales, Juan Miguel, Quiles, David, Romanov, Filipp D., Lane, David J., Richmond, Michael, Ruocco, Nello, Sano, Yasuo, Spearman, Mark, Schmidt, Richard, Vanmunster, Tonny, Dubovsky, Pavol A., Wagner, Richard, Wollenhaupt, Guido, Lorenz, Joachim, Lehmann, Gerhard, Salewski, Andrea, and Williamson, Guy
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present our optical photometric observations of the 2022 eruption of the recurrent nova U Scorpii (U Sco) using 49,152 data points over 70 d following the optical peak. We have also analyzed its soft X-ray (0.3--1 keV) light curve by the Neil Gehrels Swift Observatory. During the 2022 eruption, the optical plateau stage started 13.8--15.0 d and ended 23.8--25.0 d after the optical peak. The soft X-ray stage started 14.6--15.3 d and ended 38.7--39.5 d after the optical peak. Both stages started later and had shorter durations, and the soft X-ray light curve peaked earlier and was less luminous compared to those during the U Sco 2010 eruption. These points suggest that there were differences in the envelope mass between the different cycles of the nova eruption. Furthermore, we have analyzed the optical eclipses during the 2022 eruption. The primary eclipse was first observed 10.4--11.6 d after the optical peak, earlier than the beginning of the optical plateau stage. This sequence of events can be explained by the receding ejecta photosphere associated with the expanding nova ejecta. We have determined the ingress and egress phases of the primary eclipses and estimated the outer radius of the optical light source centered at the white dwarf (WD). During the optical plateau stage, the source radius remained $\sim$1.2 times larger than the Roche volume radius of the primary WD, being close to the L1 point. When the optical plateau stage ended, the source radius drastically shrank to the tidal truncation radius within a few orbital periods. This previously unresolved phenomenon can be interpreted as a structural change in U Sco where the temporarily expanded accretion disk due to the nova wind returned to a steady state., Comment: 16 pages, 7 figures, 7 tables, accepted for publication in PASJ; doi:10.1093/pasj/psae010
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- 2024
38. Plane Wave Dynamic Model of Electric Power Networks with High Shares of Inverter-Based Resources
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Sajadi, Amirhossein and Hodge, Bri-Mathias
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Electrical Engineering and Systems Science - Systems and Control - Abstract
Contemporary theories and models for electric power system stability are predicated on a widely held assumption that the mechanical inertia of the rotating mass of synchronous generators provides the sole contribution to stable and synchronized operation of this class of complex networks on subsecond timescales. Here we formulate the electromagnetic momentum of the field around the transmission lines that transports energy and present evidence from a real-world bulk power network that demonstrates its physical significance. We show the classical stability model for power networks that overlooks this property, known as the "swing equation", may become inadequate to analyze systems with high shares of inverter-based resources, commonly known as "low-inertia power systems". Subsequently, we introduce a plane wave dynamic model, consistent with the structural properties of emerging power systems with up to 100% inverter-based resources, which identifies the concept of inertia in power grids as a time-varying component. We leverage our theory to discuss a number of open questions in the electric power industry. Most notably, we postulate that the changing nature of power networks with a preponderance of variable renewable energy power plants could strengthen power network stability in the future; a vision which is irreconcilable with the conventional theories.
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- 2024
39. Towards Robust and Scalable Dispatch Modeling of Long-Duration Energy Storage
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Guerra, Omar J., Dalvi, Sourabh, Thatte, Amogh A., Cowiestoll, Brady, Jorgenson, Jennie, and Hodge, Bri-Mathias
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Electrical Engineering and Systems Science - Systems and Control - Abstract
Existing modeling approaches for long-duration energy storage (LDES) are often based either on an oversimplified representation of power system operations or limited representation of storage technologies, e.g., evaluation of only a single application. This manuscript presents an overview of the challenges of modeling LDES technologies, as well as a discussion regarding the capabilities and limitations of existing approaches. We used two test power systems with high shares of both solar photovoltaics- and wind (70% - 90% annual variable renewable energy shares) to assess LDES dispatch approaches. Our results estimate that better dispatch modeling of LDES could increase the associated operational value by 4% - 14% and increase the standard capacity credit by 14% - 34%. Thus, a better LDES dispatch could represent significant cost saving opportunities for electric utilities and system operators. In addition, existing LDES dispatch modeling approaches were tested in terms of both improved system value (e.g., based on production cost and standard capacity credit) and scalability (e.g., based on central processing unit time and peak memory usage). Both copper plate and nodal representations of the power system were considered. Although the end volume target dispatch approach, i.e., based on mid-term scheduling, showed promising performance in terms of both improved system value and scalability, there is a need for robust and scalable dispatch approaches for LDES in transmission-constrained electric grids. Moreover, more research is required to better understand the optimal operation of LDES considering extreme climate/weather events, reliability applications, and power system operational uncertainties., Comment: 45 pages, 16 figures, Submitted to Renewable and Sustainable Energy Reviews
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- 2024
40. At the end of cosmic noon: Short gas depletion times in unobscured quasars at $z \sim$ 1
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Castillo, M. Frias, Rybak, M., Hodge, J., van der Werf, P., Abbo, L. J., Ballieux, F. J., Ward, S., Harrison, C., Rivera, G. Calistro, McKean, J. P., and Stacey, H. R.
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Astrophysics - Astrophysics of Galaxies - Abstract
Unobscured quasars (QSOs) are predicted to be the final stage in the evolutionary sequence from gas-rich mergers to gas-depleted, quenched galaxies. Studies of this population, however, find a high incidence of far-infrared-luminous sources -suggesting significant dust-obscured star formation-but direct observations of the cold molecular gas fuelling this star formation are still necessary. We present a NOEMA study of CO(2-1) emission, tracing the cold molecular gas, in ten lensed z=1-1.5 unobscured QSOs. We detected CO(2-1) in seven of our targets, four of which also show continuum emission (\lambda_rest = 1.3mm). After subtracting the foreground galaxy contribution to the photometry, spectral energy distribution fitting yielded stellar masses of 10^9-11 M_\odot, with star formation rates of 25-160 M_\odot yr^-1 for the host galaxies. These QSOs have lower $L'_\mathrm{CO}$ than star-forming galaxies with the same L_IR, and show depletion times spanning a large range (50-900 Myr), but with a median of just 90 Myr. We find molecular gas masses in the range 2-40 x 10^9(alpha_CO/4) M_\odot, which suggest gas fractions above ~50% for most of the targets. Despite the presence of an unobscured QSO, the host galaxies are able to retain significant amounts of cold gas. However, with a median depletion time of ~90 Myr, the intense burst of star formation taking place in these targets will quickly deplete their molecular gas reservoirs in the absence of gas replenishment, resulting in a quiescent host galaxy. The non-detected QSOs are three of the four radio-loud QSOs in the sample, and their properties indicate that they are likely already transitioning into quiescence. Recent cosmological simulations tend to overestimate the depletion times expected for these z~1 QSO-host galaxies, which is likely linked to their difficulty producing starbursts across the general high-redshift galaxy population., Comment: 20 pages. Accepted for publication in A&A
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- 2024
41. Modulating patient output: rethinking the role of EM in the healthcare system
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Lang-Hodge, Annmarie M., Monaghan, Melissa N., Lim, Rodrick, Heymann, Eric P., and Lang, Eddy
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- 2024
- Full Text
- View/download PDF
42. Dietary factors and DNA methylation-based markers of ageing in 5310 middle-aged and older Australian adults
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Cribb, Lachlan, Hodge, Allison M., Southey, Melissa C., Giles, Graham G., Milne, Roger L., and Dugué, Pierre-Antoine
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- 2024
- Full Text
- View/download PDF
43. Dietary patterns derived by reduced rank regression, macronutrients as response variables, and variation by economic status: NHANES 1999–2018
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Coxall, Samuel C., Albers, Frances EM., Li, Sherly X., Shi, Zumin, Hodge, Allison M., Lynch, Brigid M., and Melaku, Yohannes Adama
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- 2024
- Full Text
- View/download PDF
44. Are dilution, slow injection and care bolus technique the causal solution to mitigating arterial-phase artifacts on gadoxetic acid–enhanced MRI? A large-cohort study
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Poetter-Lang, Sarah, Ambros, Raphael, Messner, Alina, Kristic, Antonia, Hodge, Jacqueline C., Bastati, Nina, Schima, Wolfgang, Chernyak, Victoria, Bashir, Mustafa R., and Ba-Ssalamah, Ahmed
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- 2024
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45. Mesenchymal Stem Cell Therapy in Acute Intracerebral Hemorrhage: A Dose-Escalation Safety and Tolerability Trial
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Durand, Nisha C., Kim, H. G., Patel, Vishal N., Turnbull, Marion T., Siegel, Jason L., Hodge, David O., Tawk, Rabih G., Meschia, James F., Freeman, W. David, and Zubair, Abba C.
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- 2024
- Full Text
- View/download PDF
46. A Practical Guide to Nutrition Support in the Oncology Patient: Tips, Tricks, and Ethical Considerations
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Russell, L., Bode, A. Hodge, and Dengler, A.
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- 2024
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47. Epigenetic associations in HPA axis genes related to bronchopulmonary dysplasia and antenatal steroids
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Hodge, Kenyaita M., Zhabotynsky, Vasyl, Burt, Amber A., Carter, Brian S., Fry, Rebecca C., Helderman, Jennifer, Hofheimer, Julie A., McGowan, Elisabeth C., Neal, Charles R., Pastyrnak, Steven L., Smith, Lynne M., DellaGrotta, Sheri A., Dansereau, Lynne M., Lester, Barry M., Marsit, Carmen J., O’Shea, T. Michael, and Everson, Todd M.
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- 2024
- Full Text
- View/download PDF
48. Predictive models enhance feedstock quality of corn stover via air classification
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Cousins, Dylan S., Rony, Asif Hasan, Otto, William G., Pedersen, Kristian P., Hernandez, Sergio, Lacey, Jeffrey A., Aston, John E., and Hodge, David B.
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- 2024
- Full Text
- View/download PDF
49. Poems/Poèmes
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Edwards, John, Brantingham, Philip, Huxley, Herbert H., Hodge, A. T., and Nicholson, Monique
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- 2018
50. Examining the Effect of Inquiry-Based Learning versus Traditional Lecture-Based Learning on Students' Achievement in College Algebra
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Khasawneh, Elaina, Hodge-Zickerman, Angie, York, Cindy S., Smith, Thomas J., and Mayall, Hayley
- Abstract
The focus of this study was to examine the effect of teaching based on inquiry-based learning versus traditional learning on mathematics achievement scores of undergraduate students enrolled in a college algebra class in a university classified as a Predominantly Black Institution. A college algebra course was chosen in this study due to the critical role it plays as a gateway for college completion and due to the generally high failure rate in college algebra. This study used a quasi-experimental design, with pre- and post-test to determine the effect of the instructional pedagogy on mathematics academic achievement of students. Analysis of covariance results from 41 students revealed, when controlling for college algebra readiness pre-test scores, students in the inquiry-based learning section showed significantly higher mathematics achievement post-test scores than in the traditional lecture section.
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- 2023
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