2,768 results on '"Isaac, D"'
Search Results
2. State of the California Current Ecosystem report in 2022: a tale of two La Niñas
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Thompson, Andrew R, Swalethorp, Rasmus, Alksne, Michaela, Santora, Jarrod A, Hazen, Elliott L, Leising, Andrew, Satterthwaite, Erin, Sydeman, William J, Anderson, Clarissa R, Auth, Toby D, Baumann-Pickering, Simone, Baumgardner, Timothy, Bjorkstedt, Eric P, Bograd, Steven J, Bowlin, Noelle M, Burke, Brian J, Daly, Elizabeth A, Dewar, Heidi, Field, John C, Fisher, Jennifer L, Garfield, Newell, Gidding, Ashlyn, Goericke, Ralf, Golightly, Richard, Gómez-Ocampo, Eliana, Gomez-Valdes, Jose, Hildebrand, John A, Jacobson, Kym C, Jacox, Michael G, Jahncke, Jaime, Johns, Michael, Jones, Joshua M, Lavaniegos, Bertha, Mantua, Nate, McChesney, Gerard J, Medina, Megan E, Melin, Sharon R, Miranda, Luis Erasmo, Morgan, Cheryl A, Nickels, Catherine F, Orben, Rachael A, Porquez, Jessica M, Preti, Antonella, Robertson, Roxanne R, Rudnick, Daniel L, Sakuma, Keith M, Schacter, Carley R, Schroeder, Isaac D, Scopel, Lauren, Snodgrass, Owyn E, Thompson, Sarah Ann, Warzybok, Pete, Whitaker, Katherine, Watson, William, Weber, Edward D, and Wells, Brian
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Earth Sciences ,Oceanography ,Biological Sciences ,Ecology ,California Current ,marine heatwave ,La Nina/El Nino ,California Cooperative Oceanic Fisheries Investigation ,global warming ,Geology - Abstract
2022 marked the third consecutive La Niña and extended the longest consecutive stretch of negative Oceanic Niño Index since 1998-2001. While physical and biological conditions in winter and spring largely adhered to prior La Niña conditions, summer and fall were very different. Similar to past La Niña events, in winter and spring coastal upwelling was either average or above average, temperature average or below average, salinity generally above average. In summer and fall, however, upwelling and temperature were generally average or slightly below average, salinity was close to average and chlorophyll a was close to average. Again, as during prior La Niña events, biomass of northern/southern copepods was above/below average off Oregon in winter, and body size of North Pacific krill in northern California was above average in winter. By contrast, later in the year the abundance of northern krill dropped off Oregon while southern copepods increased and body sizes of North Pacific krill fell in northern California. Off Oregon and Washington abundances of market squid and Pacific pompano (indicators of warm, non-typical La Niña conditions) were high. In the 20th century, Northern anchovy recruitment tended to be high during cold conditions, but despite mostly warm conditions from 2015-2021 anchovy populations boomed and remained high in 2022. Resident seabird reproductive success, which tended in the past to increase during productive La Niña conditions was highly variable throughout the system as common murre and pelagic cormorant, experienced complete reproductive failure at Yaquina Head, Oregon while Brandt’s cormorant reproduction was average. At three sampling locations off central California, however, common murre reproduction was close to or above average while both pelagic and Brandt’s cormorant were above average. California sealion reproduction has been above average each year since 2016, and pup weight was also above average in 2022, likely in response not to La Niña or El Niño but continuous high abundance of anchovy. The highly variable and often unpredictable physical and biological conditions in 2022 highlight a growing recognition of disconnects between basin-scale indices and local conditions in the CCE. “July-December 2022 is the biggest outlier from individual “strong” La Niña (events) ever going back to the 50s.” – Nate Mantua
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- 2024
3. An Eclipsing 47 minute Double White Dwarf Binary at 400 pc
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Munday, James, Tremblay, P. -E., Hermes, J. J., Barlow, Brad, Pelisoli, Ingrid, Marsh, T. R., Parsons, Steven G., Jones, David, Kepler, S. O., Brown, Alex, Littlefair, S. P., Hegedus, R., Baran, Andrzej, Breedt, Elmé, Dhillon, V. S., Dyer, Martin J., Green, Matthew J., Kennedy, Mark R., Kerry, Paul, Lopez, Isaac D., Romero, Alejandra D., Sahman, Dave, and Worters, Hannah L.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
We present the discovery of the eclipsing double white dwarf (WD) binary WDJ 022558.21-692025.38 that has an orbital period of 47.19 min. Following identification with the Transiting Exoplanet Survey Satellite, we obtained time-series ground based spectroscopy and high-speed multi-band ULTRACAM photometry which indicate a primary DA WD of mass 0.40 +- 0.04 Msol and a 0.28 +- 0.02 Msol mass secondary WD, which is likely of type DA as well. The system becomes the third-closest eclipsing double WD binary discovered with a distance of approximately 400 pc and will be a detectable source for upcoming gravitational wave detectors in the mHz frequency range. Its orbital decay will be measurable photometrically within 10 yrs to a precision of better than 1%. The fate of the binary is to merge in approximately 41 Myr, likely forming a single, more massive WD., Comment: Accepted for publication in MNRAS, 8 pages + 2 appendix pages, 6 figures
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- 2023
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4. Near-infrared excitation Raman spectroscopy of colored fabric contaminated with body fluids
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Juárez, Isaac D. and Kurouski, Dmitry
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- 2024
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5. Dawn of diverse shelled and carbonaceous animal microfossils at ~ 571 Ma
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Morais, Luana, Freitas, Bernardo T., Fairchild, Thomas Rich, Clavijo Arcos, Rolando Esteban, Guillong, Marcel, Vance, Derek, de Campos, Marcelo Da Roz, Babinski, Marly, Pereira, Luiz Gustavo, Leme, Juliana M., Boggiani, Paulo C., Osés, Gabriel L., Rudnitzki, Isaac D., Galante, Douglas, Rodrigues, Fabio, and Trindade, Ricardo I. F.
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- 2024
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6. Exploring the internal rotation of the extremely low-mass He-core white dwarf GD 278 with TESS asteroseismology
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Calcaferro, Leila M., Córsico, Alejandro H., Althaus, Leandro G., Lopez, Isaac D., and Hermes, J. J.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
(Abridged) We present an exploration of the internal rotation of GD 278, the first pulsating extremely low-mass white dwarf that shows rotational splittings within its periodogram. We assess the theoretical frequency splittings expected for different rotation profiles and compare them to the observed frequency splittings of GD 278. To this aim, we employ an asteroseismological model representative of the pulsations of this star, obtained by using the LPCODE stellar evolution code. We also derive a rotation profile that results from detailed evolutionary calculations carried out with the MESA stellar evolution code and use it to infer the expected theoretical frequency splittings. We found that the best-fitting solution when assuming linear profiles for the rotation of GD 278 leads to values of the angular velocity at the surface and the center that are only slightly differential, and still compatible with rigid rotation. The values of the angular velocity at the surface and the center for the simple linear rotation profiles and for the rotation profile derived from evolutionary calculations are in very good agreement. Also, the resulting theoretical frequency splittings are compatible with the observed frequency splittings, in general, for both cases. The results obtained from the different approaches followed in this work to derive the internal rotation of GD 278 agree. The fact that they were obtained employing two independent stellar evolution codes gives robustness to our results. Our results suggest only a marginally differential behavior for the internal rotation in GD 278, and considering the uncertainties involved, very compatible with the rigid case, as has been observed previously for white dwarfs and pre-white dwarfs. The rotation periods derived for this star are also in line with the values determined asteroseismologically for white dwarfs and pre-white dwarfs in general., Comment: 9 pages, 6 figures. Accepted for publication in Astronomy & Astrophysics
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- 2023
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7. Near-infrared excitation Raman spectroscopy of colored fabric contaminated with body fluids
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Isaac D. Juárez and Dmitry Kurouski
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Medicine ,Science - Abstract
Abstract Confirmatory identification of dyes in the physical pieces of evidence, such as hair and fabric, is critically important in forensics. This information can be used to demonstrate the link between a person of interest and a crime scene. High performance liquid chromatography is broadly used for dye analysis. However, this technique is destructive and laborious. This problem can be overcome by near-Infrared excitation Raman spectroscopy (NIeRS), non-invasive and non-destructive technique that can be used to determine chemical structure of highly fluorescent dyes. Analyzed fabric materials often possess body fluid stains, which may obscure the accuracy of NIeRS-based identification of dyes. In this study, we investigate the extent to which fabric contamination with body fluids can alter the accuracy of NIeRS. Our results showed that NIeRS coupled with partial-least squared discriminant analysis (PLS-DA) enabled on average 97.6% accurate identification of dyes on fabric contaminated with dry blood, urine and semen. We also found that NIeRS could be used to identify blood, urine and semen on such fabric with 99.4% accuracy. Furthermore, NIeRS could be used to differentiate between wet and dry blood, as well as reveal the presence of blood on washed fabric. These results indicate that NIeRS coupled with PLS-DA could be used as a robust and reliable analytical approach in forensic analysis of fabric.
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- 2024
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8. Dawn of diverse shelled and carbonaceous animal microfossils at ~ 571 Ma
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Luana Morais, Bernardo T. Freitas, Thomas Rich Fairchild, Rolando Esteban Clavijo Arcos, Marcel Guillong, Derek Vance, Marcelo Da Roz de Campos, Marly Babinski, Luiz Gustavo Pereira, Juliana M. Leme, Paulo C. Boggiani, Gabriel L. Osés, Isaac D. Rudnitzki, Douglas Galante, Fabio Rodrigues, and Ricardo I. F. Trindade
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Medicine ,Science - Abstract
Abstract The Ediacaran-Cambrian transition documents a critical stage in the diversification of animals. The global fossil record documents the appearance of cloudinomorphs and other shelled tubular organisms followed by non-biomineralized small carbonaceous fossils and by the highly diversified small shelly fossils between ~ 550 and 530 Ma. Here, we report diverse microfossils in thin sections and hand samples from the Ediacaran Bocaina Formation, Brazil, separated into five descriptive categories: elongate solid structures (ES); elongate filled structures (EF); two types of equidimensional structures (EQ 1 and 2) and elongate hollow structures with coiled ends (CE). These specimens, interpreted as diversified candidate metazoans, predate the latest Ediacaran biomineralized index macrofossils of the Cloudina-Corumbella-Namacalathus biozone in the overlying Tamengo Formation. Our new carbonate U–Pb ages for the Bocaina Formation, position this novel fossil record at 571 ± 9 Ma (weighted mean age). Thus, our data point to diversification of metazoans, including biomineralized specimens reminiscent of sections of cloudinids, protoconodonts, anabaritids, and hyolithids, in addition to organo-phosphatic surficial coverings of animals, demonstrably earlier than the record of the earliest known skeletonized metazoan fossils.
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- 2024
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9. The Min-Entropy of Classical-Quantum Combs for Measurement-Based Applications
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Smith, Isaac D., Krumm, Marius, Fiderer, Lukas J., Nautrup, Hendrik Poulsen, and Briegel, Hans J.
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Quantum Physics - Abstract
Learning a hidden property of a quantum system typically requires a series of interactions. In this work, we formalise such multi-round learning processes using a generalisation of classical-quantum states, called classical-quantum combs. Here, "classical" refers to a random variable encoding the hidden property to be learnt, and "quantum" refers to the quantum comb describing the behaviour of the system. The optimal strategy for learning the hidden property can be quantified by applying the comb min-entropy (Chiribella and Ebler, NJP, 2016) to classical-quantum combs. To demonstrate the power of this approach, we focus attention on an array of problems derived from measurement-based quantum computation (MBQC) and related applications. Specifically, we describe a known blind quantum computation (BQC) protocol using the combs formalism and thereby leverage the min-entropy to provide a proof of single-shot security for multiple rounds of the protocol, extending the existing result in the literature. Furthermore, we consider a range of operationally motivated examples related to the verification of a partially unknown MBQC device. These examples involve learning the features of the device necessary for its correct use, including learning its internal reference frame for measurement calibration. We also introduce a novel connection between MBQC and quantum causal models that arises in this context., Comment: 24 + 17 pages, 11 figures; Modifications to the presentation; some additional results added. Accepted in Quantum 2023-12-01
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- 2022
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10. Contemporary applications of vibrational spectroscopy in plant stresses and phenotyping
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Isaac D. Juárez and Dmitry Kurouski
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digital farming ,non-invasive phenotyping ,nutrient content assessment ,plant disease diagnostics ,Raman spectroscopy ,optical sensing ,Plant culture ,SB1-1110 - Abstract
Plant pathogens, including viruses, bacteria, and fungi, cause massive crop losses around the world. Abiotic stresses, such as drought, salinity and nutritional deficiencies are even more detrimental. Timely diagnostics of plant diseases and abiotic stresses can be used to provide site- and doze-specific treatment of plants. In addition to the direct economic impact, this “smart agriculture” can help minimizing the effect of farming on the environment. Mounting evidence demonstrates that vibrational spectroscopy, which includes Raman (RS) and infrared spectroscopies (IR), can be used to detect and identify biotic and abiotic stresses in plants. These findings indicate that RS and IR can be used for in-field surveillance of the plant health. Surface-enhanced RS (SERS) has also been used for direct detection of plant stressors, offering advantages over traditional spectroscopies. Finally, all three of these technologies have applications in phenotyping and studying composition of crops. Such non-invasive, non-destructive, and chemical-free diagnostics is set to revolutionize crop agriculture globally. This review critically discusses the most recent findings of RS-based sensing of biotic and abiotic stresses, as well as the use of RS for nutritional analysis of foods.
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- 2024
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11. Progressive Diffusion Autofocus for Synthetic Aperture Sonar Imagery.
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Balkan V. Bingol, Isaac D. Gerg, and Vishal Monga
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- 2024
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12. Uncovering Bias in Building Damage Assessment from Satellite Imagery.
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Dennis Melamed, Cameron Johnson, Isaac D. Gerg, Chen Zhao, Russell Blue, Anthony Hoogs, Brian Clipp, and Philip Morrone
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- 2024
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13. Cybersecurity Risk Audit: A Systematic Literature Review
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Sanchez-Garcia, Isaac D., Rea-Guaman, Angel M., Gilabert, Tomás San Feliu, Calvo-Manzano, Jose A., Kacprzyk, Janusz, Series Editor, Mejía, Jezreel, editor, Muñoz, Mirna, editor, Rocha, Alvaro, editor, Hernández Pérez, Yasmin, editor, and Avila-George, Himer, editor
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- 2024
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14. De novo design of high-affinity binders of bioactive helical peptides
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Vázquez Torres, Susana, Leung, Philip J. Y., Venkatesh, Preetham, Lutz, Isaac D., Hink, Fabian, Huynh, Huu-Hien, Becker, Jessica, Yeh, Andy Hsien-Wei, Juergens, David, Bennett, Nathaniel R., Hoofnagle, Andrew N., Huang, Eric, MacCoss, Michael J., Expòsit, Marc, Lee, Gyu Rie, Bera, Asim K., Kang, Alex, De La Cruz, Joshmyn, Levine, Paul M., Li, Xinting, Lamb, Mila, Gerben, Stacey R., Murray, Analisa, Heine, Piper, Korkmaz, Elif Nihal, Nivala, Jeff, Stewart, Lance, Watson, Joseph L., Rogers, Joseph M., and Baker, David
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- 2024
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15. Ziphius cavirostris presence relative to the vertical and temporal variability of oceanographic conditions in the Southern California Bight
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Clara M. Schoenbeck, Alba Solsona‐Berga, Peter J. S. Franks, Kaitlin E. Frasier, Jennifer S. Trickey, Catalina Aguilar, Isaac D. Schroeder, Ana Širović, Steven J. Bograd, Ganesh Gopalakrishnan, and Simone Baumann‐Pickering
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Cuvier's beaked whales ,echolocation clicks ,El Niño ,habitat model ,optimum multiparameter analysis ,passive acoustic monitoring ,Ecology ,QH540-549.5 - Abstract
Abstract The oceanographic conditions of the Southern California Bight (SCB) dictate the distribution and abundance of prey resources and therefore the presence of mobile predators, such as goose‐beaked whales (Ziphius cavirostris). Goose‐beaked whales are deep‐diving odontocetes that spend a majority of their time foraging at depth. Due to their cryptic behavior, little is known about how they respond to seasonal and interannual changes in their environment. This study utilizes passive acoustic data recorded from two sites within the SCB to explore the oceanographic conditions that goose‐beaked whales appear to favor. Utilizing optimum multiparameter analysis, modeled temperature and salinity data are used to identify and quantify these source waters: Pacific Subarctic Upper Water (PSUW), Pacific Equatorial Water (PEW), and Eastern North Pacific Central Water (ENPCW). The interannual and seasonal variability in goose‐beaked whale presence was related to the variability in El Niño Southern Oscillation events and the fraction and vertical distribution of the three source waters. Goose‐beaked whale acoustic presence was highest during the winter and spring and decreased during the late summer and early fall. These seasonal increases occurred at times of increased fractions of PEW in the California Undercurrent and decreased fractions of ENPCW in surface waters. Interannual increases in goose‐beaked whale presence occurred during El Niño events. These results establish a baseline understanding of the oceanographic characteristics that correlate with goose‐beaked whale presence in the SCB. Furthering our knowledge of this elusive species is key to understanding how anthropogenic activities impact goose‐beaked whales.
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- 2024
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16. Iterative, Deep Synthetic Aperture Sonar Image Segmentation
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Sun, Yung-Chen, Gerg, Isaac D., and Monga, Vishal
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Computer Science - Computer Vision and Pattern Recognition - Abstract
Synthetic aperture sonar (SAS) systems produce high-resolution images of the seabed environment. Moreover, deep learning has demonstrated superior ability in finding robust features for automating imagery analysis. However, the success of deep learning is conditioned on having lots of labeled training data, but obtaining generous pixel-level annotations of SAS imagery is often practically infeasible. This challenge has thus far limited the adoption of deep learning methods for SAS segmentation. Algorithms exist to segment SAS imagery in an unsupervised manner, but they lack the benefit of state-of-the-art learning methods and the results present significant room for improvement. In view of the above, we propose a new iterative algorithm for unsupervised SAS image segmentation combining superpixel formation, deep learning, and traditional clustering methods. We call our method Iterative Deep Unsupervised Segmentation (IDUS). IDUS is an unsupervised learning framework that can be divided into four main steps: 1) A deep network estimates class assignments. 2) Low-level image features from the deep network are clustered into superpixels. 3) Superpixels are clustered into class assignments (which we call pseudo-labels) using $k$-means. 4) Resulting pseudo-labels are used for loss backpropagation of the deep network prediction. These four steps are performed iteratively until convergence. A comparison of IDUS to current state-of-the-art methods on a realistic benchmark dataset for SAS image segmentation demonstrates the benefits of our proposal even as the IDUS incurs a much lower computational burden during inference (actual labeling of a test image). Finally, we also develop a semi-supervised (SS) extension of IDUS called IDSS and demonstrate experimentally that it can further enhance performance while outperforming supervised alternatives that exploit the same labeled training imagery., Comment: arXiv admin note: text overlap with arXiv:2107.14563
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- 2022
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17. Deep Adaptive Phase Learning: Enhancing Synthetic Aperture Sonar Imagery Through Learned Coherent Autofocus
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Isaac D. Gerg, Daniel A. Cook, and Vishal Monga
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Deep Learning ,image enhancement ,synthetic aperture sonar ,Ocean engineering ,TC1501-1800 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Having well-focused synthetic aperture sonar (SAS) imagery is important for its accurate analysis and support of autonomous systems. Despite advances in motion estimation and image formation methods, there persists a need for robust autofocus algorithms deployed both topside and in situ embedded in unmanned underwater vehicles (UUVs) for real-time processing. This need stems from the fact that systematic focus errors are common in SAS and often result from misestimating sound speed in the medium or uncompensated vehicle motion. In this article, we use an SAS-specific convolutional neural network (CNN) to robustly and quickly autofocus SAS images. Our method, which we call deep adaptive phase learning (DAPL), explicitly utilizes the relationship between the $k$-space domain and the complex-valued SAS image to perform the autofocus operation in a manner distinctly different than existing optical image deblurring techniques that solely rely on magnitude-only imagery. We demonstrate that DAPL mitigates three types of systematic phase errors common to SAS platforms (and combinations thereof): quadratic phase error (QPE), sinusoidal error, and sawtooth error (i.e., yaw error). We show results for DAPL against a publicly available, real-world high-frequency SAS dataset, and also compare them against several existing techniques including phase gradient autofocus (PGA). Our results show that DAPL is competitive with or outperforms state-of-the-art alternatives without requiring manual parameter tuning.
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- 2024
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18. Ecological forecasts for marine resource management during climate extremes
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Stephanie Brodie, Mercedes Pozo Buil, Heather Welch, Steven J. Bograd, Elliott L. Hazen, Jarrod A. Santora, Rachel Seary, Isaac D. Schroeder, and Michael G. Jacox
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Science - Abstract
Abstract Forecasting weather has become commonplace, but as society faces novel and uncertain environmental conditions there is a critical need to forecast ecology. Forewarning of ecosystem conditions during climate extremes can support proactive decision-making, yet applications of ecological forecasts are still limited. We showcase the capacity for existing marine management tools to transition to a forecasting configuration and provide skilful ecological forecasts up to 12 months in advance. The management tools use ocean temperature anomalies to help mitigate whale entanglements and sea turtle bycatch, and we show that forecasts can forewarn of human-wildlife interactions caused by unprecedented climate extremes. We further show that regionally downscaled forecasts are not a necessity for ecological forecasting and can be less skilful than global forecasts if they have fewer ensemble members. Our results highlight capacity for ecological forecasts to be explored for regions without the infrastructure or capacity to regionally downscale, ultimately helping to improve marine resource management and climate adaptation globally.
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- 2023
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19. New Variable Hot Subdwarf Stars Identified from Anomalous Gaia Flux Errors, Observed by TESS, and Classified via Fourier Diagnostics
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Barlow, Brad N., Corcoran, Kyle A., Parker, Isabelle M., Kupfer, Thomas, Németh, Péter, Hermes, J. J., Lopez, Isaac D., Frondorf, Will J., Vestal, David, and Holden, Jazzmyn
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Astrophysics - Solar and Stellar Astrophysics - Abstract
Hot subdwarf stars are mostly stripped red giants that can exhibit photometric variations due to stellar pulsations, eclipses, the reflection effect, ellipsoidal modulation, and Doppler beaming. Detailed studies of their light curves help constrain stellar parameters through asteroseismological analyses or binary light curve modeling and generally improve our capacity to draw a statistically meaningful picture of this enigmatic stage of stellar evolution. From an analysis of Gaia DR2 flux errors, we have identified around 1200 candidate hot subdwarfs with inflated flux errors for their magnitudes - a strong indicator of photometric variability. As a pilot study, we obtained 2-min cadence TESS Cycle 2 observations of 187 candidate hot subdwarfs with anomalous Gaia flux errors. More than 90% of our targets show significant photometric variations in their TESS light curves. Many of the new systems found are cataclysmic variables, but we report the discovery of several new variable hot subdwarfs, including HW Vir binaries, reflection effect systems, pulsating sdBVs stars, and ellipsoidally modulated systems. We determine atmospheric parameters for select systems using follow-up spectroscopy from the 3-m Shane telescope. Finally, we present a Fourier diagnostic plot for classifying binary light curves using the relative amplitudes and phases of their fundamental and harmonic signals in their periodograms. This plot makes it possible to identify certain types of variables efficiently, without directly investigating their light curves, and may assist in the rapid classification of systems observed in large photometric surveys., Comment: 24 pages, 18 figures, 5 tables; accepted for publication in ApJ
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- 2021
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20. Elucidating the antimalarial activity of pityriacitrin isolated from Strophanthus hispidus (DC) whole plant extract: A detailed experimental and in-silico investigation
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Faloye, Kolade O., Ambali, Owoola A., Ogundele, Seun B., Tripathi, Manish K., Adesida, Stephen A., Asiyanbola, Isaac D., Fakola, Emmanuel G., Obaidullah, Ahmad J., Alotaibi, Jawaher M., and Oguntimehin, Samuel A.
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- 2024
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21. New Medical Device and Therapeutic Approvals in Otolaryngology: State of the Art Review of 2021
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Choi, Alexander M, Brenner, Michael J, Gorelik, Daniel, Erbele, Isaac D, Crowson, Matthew G, Kadkade, Prajoy, Takashima, Masayoshi, Santa Maria, Peter L, Hong, Robert S, Rose, Austin S, Ostrander, Benjamin T, Rabbani, Cyrus C, Morrison, Robert J, Weissbrod, Philip A, Tate, Alan D, Kain, Joshua J, Lina, Ioan A, Shaffer, Scott R, and Ahmed, Omar G
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Biomedical and Clinical Sciences ,Clinical Sciences ,Rare Diseases ,Orphan Drug ,Dental/Oral and Craniofacial Disease ,Patient Safety ,Bioengineering ,medical devices ,drugs ,FDA ,therapeutic - Abstract
ObjectiveTo evaluate new medical devices and drugs pertinent to otolaryngology-head and neck surgery that were approved by the Food and Drug Administration (FDA) in 2021.Data sourcesPublicly available FDA device and drug approvals from ENT (ear, nose, and throat), anesthesia, neurosurgery, plastic surgery, and general surgery FDA committees.Review methodsFDA device and therapeutic approvals were identified and reviewed by members of the American Academy of Otolaryngology-Head and Neck Surgery's Medical Devices and Drugs Committee. Two independent reviewers assessed the relevance of devices and drugs to otolaryngologists. Medical devices and drugs were then allocated to their respective subspecialty fields for critical review based on available scientific literature.ConclusionsThe Medical Devices and Drugs Committee reviewed 1153 devices and 52 novel drugs that received FDA approval in 2021 (67 ENT, 106 anesthesia, 618 general surgery and plastic surgery, 362 neurosurgery). Twenty-three devices and 1 therapeutic agent relevant to otolaryngology were included in the state of the art review. Advances spanned all subspecialties, including over-the-counter hearing aid options in otology, expanding treatment options for rhinitis in rhinology, innovative laser-safe endotracheal tubes in laryngology, novel facial rejuvenation and implant technology in facial plastic surgery, and advances in noninvasive and surgical treatment options for obstructive sleep apnea.Implications for practiceFDA approvals for new technology and pharmaceuticals present new opportunities across subspecialties in otolaryngology. Clinicians' nuanced understanding of the safety, advantages, and limitations of these innovations ensures ongoing progress in patient care.
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- 2022
22. Discovery, TESS Characterization, and Modeling of Pulsations in the Extremely Low Mass White Dwarf GD 278
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Lopez, Isaac D., Hermes, J. J., Calcaferro, Leila M., Bell, Keaton J., Samuels, Adam, Vanderbosch, Zachary P., Córsico, Alejandro H., and Istrate, Alina G.
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Astrophysics - Solar and Stellar Astrophysics - Abstract
We report the discovery of pulsations in the extremely low mass (ELM), likely helium-core white dwarf GD 278 via ground- and space-based photometry. GD 278 was observed by the Transiting Exoplanet Survey Satellite (TESS) in Sector 18 at a 2-min cadence for roughly 24 d. The TESS data reveal at least 19 significant periodicities between 2447-6729 s, one of which is the longest pulsation period ever detected in a white dwarf. Previous spectroscopy found that this white dwarf is in a 4.61 hr orbit with an unseen >0.4 solar-mass companion and has Teff = 9230 +/- 100 K and log(g) = 6.627 +/- 0.056, which corresponds to a mass of 0.191 +/- 0.013 solar mass. Patterns in the TESS pulsation frequencies from rotational splittings appear to reveal a stellar rotation period of roughly 10 hr, making GD 278 the first ELM white dwarf with a measured rotation rate. The patterns inform our mode identification for asteroseismic fits, which unfortunately do not reveal a global best-fit solution. Asteroseismology reveals two main solutions roughly consistent with the spectroscopic parameters of this ELM white dwarf, but with vastly different hydrogen-layer masses; future seismic fits could be further improved by using the stellar parallax. GD 278 is now the tenth known pulsating ELM white dwarf; it is only the fifth known to be in a short-period binary, but is the first with extended, space-based photometry., Comment: 14 pages, 10 figures, accepted for publication in the Astrophysical Journal
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- 2021
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23. Continuous white noise exposure during sleep and childhood development: A scoping review
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De Jong, Russell W., Davis, Gavin S., Chelf, Cynthia J., Marinelli, John P., Erbele, Isaac D., and Bowe, Sarah N.
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- 2024
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24. Assessing chemostratigraphic and biostratigraphic correlation of Ediacaran phosphorites (Bocaina, Khesen and Doushantuo Formations): Diachronic, local signals of the Neoproterozoic phosphogenic-taphonomic event
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Hippertt, João Pedro T.M., Rudnitzki, Isaac D., Morais, Luana, Freitas, Bernardo T., Romero, Guilherme R., Babinski, Marly, Leite, Mariangela G.P., Leme, Juliana M., Nalini, Hermínio A., Nogueira, Leonardo B., and Trindade, Ricardo I.F.
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- 2024
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25. Ecological forecasts for marine resource management during climate extremes
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Brodie, Stephanie, Pozo Buil, Mercedes, Welch, Heather, Bograd, Steven J., Hazen, Elliott L., Santora, Jarrod A., Seary, Rachel, Schroeder, Isaac D., and Jacox, Michael G.
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- 2023
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26. Optimisation of analytical methods for tuberculosis drug detection in wastewater: A multinational study
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Hlengiwe N. Mtetwa, Isaac D. Amoah, Sheena Kumari, Faizal Bux, and Poovendhree Reddy
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Tuberculosis drugs ,wastewater analysis ,Chromatography ,Wastewater-based epidemiology ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Wastewater-based epidemiology (WBE) is a robust tool for disease surveillance and monitoring of pharmaceutical consumption. However, monitoring tuberculosis (TB) drug consumption faces challenges due to limited data availability. This study aimed to optimise methods for detecting TB drugs in treated and untreated wastewater from four African countries: South Africa, Nigeria, Kenya, and Cameroon. The limit of detection (LOD) for these drugs ranged from a minimum of 2.20 (±1.02) for rifampicin to a maximum of 2.95 (±0.79) for pyrazinamide. A parallel trend was observed concerning the limit of quantification (LOQ), with rifampicin reporting the lowest average LOQ of 7.33 (±3.44) and pyrazinamide showing the highest average LOQ of 9.81 (±2.64). The variance in LOD and LOQ values could be attributed to factors such as drug polarity. Erythromycin and rifampicin exhibited moderately polar LogP values (2.6 and 2.95), indicating higher lipid affinity and lower water affinity.Conversely, ethambutol, pyrazinamide, and isoniazid displayed polar LogP values (−0.059, −0.6, and −0.7), suggesting lower lipid affinity and greater water affinity. The study revealed that storing wastewater samples for up to 5 days did not result in significant drug concentration loss, with concentration reduction remaining below 1 log throughout the storage period. Application of the optimised method for drug detection and quantification in both treated and untreated wastewater unveiled varied results. Detection frequencies varied among drugs, with ethambutol consistently most detected, while pyrazinamide and isoniazid were least detected in wastewater from only two countries. Most untreated wastewater samples had undetectable drug concentrations, ranging from 1.21 ng/mL for erythromycin to 54.61 ng/mL for isoniazid. This variability may suggest differences in drug consumption within connected communities. In treated wastewater samples, detectable drug concentrations ranged from 1.27 ng/mL for isoniazid to 10.20 ng/mL for ethambutol. Wastewater treatment plants exhibited variable removal efficiencies for different drugs, emphasising the need for further optimisation. Detecting these drugs in treated wastewater suggests potential surface water contamination and subsequent risks of human exposure, underscoring continued research's importance.
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- 2024
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27. Diagnosing arsenic-mediated biochemical responses in rice cultivars using Raman spectroscopy
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Isaac D. Juárez, Tianyi Dou, Sudip Biswas, Endang M. Septiningsih, and Dmitry Kurouski
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Oryza sativa ,phenylpropanoids ,carotenoids ,stress pathways ,non-invasive analysis ,analytical techniques ,Plant culture ,SB1-1110 - Abstract
Rice (Oryza sativa) is the primary crop for nearly half of the world’s population. Groundwater in many rice-growing parts of the world often has elevated levels of arsenite and arsenate. At the same time, rice can accumulate up to 20 times more arsenic compared to other staple crops. This places an enormous amount of people at risk of chronic arsenic poisoning. In this study, we investigated whether Raman spectroscopy (RS) could be used to diagnose arsenic toxicity in rice based on biochemical changes that were induced by arsenic accumulation. We modeled arsenite and arsenate stresses in four different rice cultivars grown in hydroponics over a nine-day window. Our results demonstrate that Raman spectra acquired from rice leaves, coupled with partial least squares-discriminant analysis, enabled accurate detection and identification of arsenic stress with approximately 89% accuracy. We also performed high-performance liquid chromatography (HPLC)-analysis of rice leaves to identify the key molecular analytes sensed by RS in confirming arsenic poisoning. We found that RS primarily detected a decrease in the concentration of lutein and an increase in the concentration of vanillic and ferulic acids due to the accumulation of arsenite and arsenate in rice. This showed that these molecules are detectable indicators of biochemical response to arsenic accumulation. Finally, a cross-correlation of RS with HPLC and ICP-MS demonstrated RS’s potential for a label-free, non-invasive, and non-destructive quantification of arsenic accumulation in rice.
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- 2024
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28. Iterative, Deep, and Unsupervised Synthetic Aperture Sonar Image Segmentation
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Sun, Yung-Chen, Gerg, Isaac D., and Monga, Vishal
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Computer Science - Computer Vision and Pattern Recognition - Abstract
Deep learning has not been routinely employed for semantic segmentation of seabed environment for synthetic aperture sonar (SAS) imagery due to the implicit need of abundant training data such methods necessitate. Abundant training data, specifically pixel-level labels for all images, is usually not available for SAS imagery due to the complex logistics (e.g., diver survey, chase boat, precision position information) needed for obtaining accurate ground-truth. Many hand-crafted feature based algorithms have been proposed to segment SAS in an unsupervised fashion. However, there is still room for improvement as the feature extraction step of these methods is fixed. In this work, we present a new iterative unsupervised algorithm for learning deep features for SAS image segmentation. Our proposed algorithm alternates between clustering superpixels and updating the parameters of a convolutional neural network (CNN) so that the feature extraction for image segmentation can be optimized. We demonstrate the efficacy of our method on a realistic benchmark dataset. Our results show that the performance of our proposed method is considerably better than current state-of-the-art methods in SAS image segmentation., Comment: IEEE OCEANS 2021
- Published
- 2021
29. Observer-Based Output Feedback Control Using Invariant Polyhedral Sets for Fuzzy T–S Models Under Constraints
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Isidório, Isaac D., Dórea, Carlos E. T., and Castelan, Eugênio B.
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- 2023
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30. Multi-dimensional modeling of H+ and OH− mass transfer during soil electro-kinetic remediation
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Zhang, Guangqiang, Tegladza, Isaac D., Fan, Yaqi, Dai, Hongliang, Wang, Mei, and Lu, Jun
- Published
- 2023
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31. Optimisation of analytical methods for tuberculosis drug detection in wastewater: A multinational study
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Mtetwa, Hlengiwe N., Amoah, Isaac D., Kumari, Sheena, Bux, Faizal, and Reddy, Poovendhree
- Published
- 2024
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32. Controlled synthesis of Ultra large diameter K2Ti6O13 micro-rods via spherical agglomeration mechanism
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Zhang, Zilu, Zhang, Chongchong, Tegladza, Isaac D., Gu, Pengliang, Che, Xinyu, and Liu, Chang
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- 2024
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33. Corrigendum: State of the California Current 2019–2020: Back to the Future With Marine Heatwaves?
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Weber, Edward D, Auth, Toby D, Baumann-Pickering, Simone, Baumgartner, Timothy R, Bjorkstedt, Eric P, Bograd, Steven J, Burke, Brian J, Cadena-Ramírez, José L, Daly, Elizabeth A, de la Cruz, Martin, Dewar, Heidi, Field, John C, Fisher, Jennifer L, Giddings, Ashlyn, Goericke, Ralf, Gomez-Ocampo, Eliana, Gomez-Valdes, Jose, Hazen, Elliott L, Hildebrand, John, Horton, Cheryl A, Jacobson, Kym C, Jacox, Michael G, Jahncke, Jaime, Kahru, Mati, Kudela, Raphe M, Lavaniegos, Bertha E, Leising, Andrew, Melin, Sharon R, Miranda-Bojorquez, Luis Erasmo, Morgan, Cheryl A, Nickels, Catherine F, Orben, Rachael A, Porquez, Jessica M, Portner, Elan J, Robertson, Roxanne R, Rudnick, Daniel L, Sakuma, Keith M, Santora, Jarrod A, Schroeder, Isaac D, Snodgrass, Owyn E, Sydeman, William J, Thompson, Andrew R, Thompson, Sarah Ann, Trickey, Jennifer S, Villegas-Mendoza, Josue, Warzybok, Pete, Watson, William, and Zeman, Samantha M
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California Current ,marine heat wave ,upwelling ,anchovy ,Ecosystem Assessment ,CalCOFI ,Oceanography ,Ecology - Published
- 2022
34. State of the California Current Ecosystem in 2021: Winter is coming?
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Thompson, Andrew R, Bjorkstedt, Eric P, Bograd, Steven J, Fisher, Jennifer L, Hazen, Elliott L, Leising, Andrew, Santora, Jarrod A, Satterthwaite, Erin V, Sydeman, William J, Alksne, Michaela, Auth, Toby D, Baumann-Pickering, Simone, Bowlin, Noelle M, Burke, Brian J, Daly, Elizabeth A, Dewar, Heidi, Field, John C, Garfield, Newell T, Giddings, Ashlyn, Goericke, Ralf, Hildebrand, John, Horton, Cheryl A, Jacobson, Kym C, Jacox, Michael G, Jahncke, Jaime, Johns, Michael, Jones, Joshua, Kudela, Raphe M, Melin, Sharon R, Morgan, Cheryl A, Nickels, Catherine F, Orben, Rachael A, Porquez, Jessica M, Portner, Elan J, Preti, Antonella, Robertson, Roxanne R, Rudnick, Daniel L, Sakuma, Keith M, Schroeder, Isaac D, Snodgrass, Owyn E, Thompson, Sarah Ann, Trickey, Jennifer S, Warzybok, Pete, Watson, William, and Weber, Edward D
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Climate Action ,California current ecosystem ,La Nina ,upwelling ,anchovy ,ecosystem assessment ,white walkers ,Oceanography ,Ecology - Abstract
In late 2020, models predicted that a strong La Niña would take place for the first time since 2013, and we assessed whether physical and biological indicators in 2021 were similar to past La Niñas in the California Current Ecosystem (CCE). The Pacific Decadal Oscillation and Oceanic Niño Index indeed remained negative throughout 2021; the North Pacific Gyre Oscillation Index, however, remained strongly negative. The seventh largest marine heatwave on record was unexpectedly present from April to the end of 2021; however, similar to past La Niñas, this mass of warm water mostly remained seaward of the continental shelf. As expected from past La Niñas, upwelling and chlorophyll were mostly high and sea surface temperature was low throughout the CCE; however, values were close to average south of Point Conception. Similar to past La Niñas, abundances of lipid-rich, northern copepods off Oregon increased. In northern California, unlike past La Niñas, the body size of North Pacific krill (Euphausia pacifica) was close to average. Predictably, overall krill abundance was above average in far northern California but, unexpectedly, below average south of Cape Mendocino. Off Oregon, similar to past La Niñas, larval abundances of three of six coastal species rose, while five of six southern/offshore taxa decreased in 2021. Off California, as expected based on 2020, Northern Anchovy (Engraulis mordax) were very abundant, while Pacific Sardine (Sardinops sagax) were low. Similar to past La Niñas, market squid (Doryteuthis opalescens) and young of the year (YOY) Pacific Hake (Merluccius pacificus), YOY sanddabs (Citharichthys spp.), and YOY rockfishes (Sebastes spp.) increased. Southern mesopelagic (e.g., Panama lightfish Vinciguerria lucetia, Mexican lampfish Triphoturus mexicanus) larvae decreased as expected but were still well above average, while northern mesopelagic (e.g., northern lampfish Stenobrachius leucopsarus) larvae increased but were still below average. In line with predictions, most monitored bird species had above-average reproduction in Oregon and California. California sea lion (Zalophus californianus) pup count, growth, and weight were high given the abundant Anchovy forage. The CCE entered an enduring La Niña in 2021, and assessing the responses of various ecosystem components helped articulate aspects of the system that are well understood and those that need further study.
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- 2022
35. Real-Time, Deep Synthetic Aperture Sonar (SAS) Autofocus
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Gerg, Isaac D. and Monga, Vishal
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Computer Science - Computer Vision and Pattern Recognition - Abstract
Synthetic aperture sonar (SAS) requires precise time-of-flight measurements of the transmitted/received waveform to produce well-focused imagery. It is not uncommon for errors in these measurements to be present resulting in image defocusing. To overcome this, an \emph{autofocus} algorithm is employed as a post-processing step after image reconstruction to improve image focus. A particular class of these algorithms can be framed as a sharpness/contrast metric-based optimization. To improve convergence, a hand-crafted weighting function to remove "bad" areas of the image is sometimes applied to the image-under-test before the optimization procedure. Additionally, dozens of iterations are necessary for convergence which is a large compute burden for low size, weight, and power (SWaP) systems. We propose a deep learning technique to overcome these limitations and implicitly learn the weighting function in a data-driven manner. Our proposed method, which we call Deep Autofocus, uses features from the single-look-complex (SLC) to estimate the phase correction which is applied in $k$-space. Furthermore, we train our algorithm on batches of training imagery so that during deployment, only a single iteration of our method is sufficient to autofocus. We show results demonstrating the robustness of our technique by comparing our results to four commonly used image sharpness metrics. Our results demonstrate Deep Autofocus can produce imagery perceptually better than common iterative techniques but at a lower computational cost. We conclude that Deep Autofocus can provide a more favorable cost-quality trade-off than alternatives with significant potential of future research., Comment: Four pages. Accepted to IGARSS 2021. Fixed Eq 9
- Published
- 2021
36. GPU Acceleration for Synthetic Aperture Sonar Image Reconstruction
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Gerg, Isaac D., Brown, Daniel C., Wagner, Stephen G., Cook, Daniel, O'Donnell, Brian N., Benson, Thomas, and Montgomery, Thomas C.
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Electrical Engineering and Systems Science - Signal Processing - Abstract
Synthetic aperture sonar (SAS) image reconstruction, or beamforming as it is often referred to within the SAS community, comprises a class of computationally intensive algorithms for creating coherent high-resolution imagery from successive spatially varying sonar pings. Image reconstruction is usually performed topside because of the large compute burden necessitated by the procedure. Historically, image reconstruction required significant assumptions in order to produce real-time imagery within an unmanned underwater vehicle's (UUV's) size, weight, and power (SWaP) constraints. However, these assumptions result in reduced image quality. In this work, we describe ASASIN, the Advanced Synthetic Aperture Sonar Imagining eNgine. ASASIN is a time domain backprojection image reconstruction suite utilizing graphics processing units (GPUs) allowing real-time operation on UUVs without sacrificing image quality. We describe several speedups employed in ASASIN allowing us to achieve this objective. Furthermore, ASASIN's signal processing chain is capable of producing 2D and 3D SAS imagery as we will demonstrate. Finally, we measure ASASIN's performance on a variety of GPUs and create a model capable of predicting performance. We demonstrate our model's usefulness in predicting run-time performance on desktop and embedded GPU hardware., Comment: 9 pages, 9 figures, submitted to MTS/IEEE OCEANS. Eq 11 fixed
- Published
- 2021
37. A Perceptual Metric Prior on Deep Latent Space Improves Out-Of-Distribution Synthetic Aperture Sonar Image Classification.
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Isaac D. Gerg and Carl F. Cotner
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- 2023
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38. CRAG: A Guideline to Perform a Cybersecurity Risk Audits
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Sánchez-García, Isaac D., Gilabert, Tomás San Feliu, Calvo-Manzano, Jose A., Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Mata-Rivera, Miguel Félix, editor, Zagal-Flores, Roberto, editor, and Barria-Huidobro, Cristian, editor
- Published
- 2023
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39. New Medical Device and Therapeutic Approvals in Otolaryngology: State of the Art Review 2020
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Brenner, Michael J, Shenson, Jared A, Rose, Austin S, Valdez, Tulio A, Takashima, Masayoshi, Ahmed, Omar G, Weissbrod, Philip A, Hong, Robert S, Djalilian, Hamid, Wolf, Jeffrey S, Morrison, Robert J, Santa Maria, Peter L, and Erbele, Isaac D
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Bioengineering ,Rare Diseases ,Patient Safety ,medical device ,therapeutic ,drug ,FDA - Abstract
ObjectivesTo evaluate new drugs and devices relevant to otolaryngology-head and neck surgery that were approved by the US Food and Drug Administration (FDA) in 2020.Data sourcesPublicly available device and therapeutic approvals from ENT (ear, nose, and throat), anesthesia, neurology (neurosurgery), and plastic and general surgery FDA committees.Review methodsMembers of the American Academy of Otolaryngology-Head and Neck Surgery's Medical Devices and Drugs Committee reviewed new therapeutics and medical devices from a query of the FDA's device and therapeutic approvals. Two independent reviewers assessed the drug's or device's relevance to otolaryngology, classified to subspecialty field, with a critical review of available scientific literature.ConclusionsThe Medical Devices and Drugs Committee reviewed 53 new therapeutics and 1094 devices (89 ENT, 140 anesthesia, 511 plastic and general surgery, and 354 neurology) approved in 2020. Ten drugs and 17 devices were considered relevant to the otolaryngology community. Rhinology saw significant improvements around image guidance systems; indications for cochlear implantation expanded; several new monoclonal therapeutics were added to head and neck oncology's armamentarium; and several new approvals appeared for facial plastics surgery, pediatric otolaryngology, and comprehensive otolaryngology.Implications for practiceNew technologies and pharmaceuticals offer the promise of improving how we care for otolaryngology patients. However, judicious introduction of innovations into practice requires a nuanced understanding of safety, advantages, and limitations. Working knowledge of new drugs and medical devices approved for the market helps clinicians tailor patient care accordingly.
- Published
- 2021
40. Profiling pathogenic protozoan and their functional pathways in wastewater using 18S rRNA and shotgun metagenomics
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Mthethwa-Hlongwa, Nonsikelelo P., Amoah, Isaac D., Gomez, Andres, Davison, Sam, Reddy, Poovendhree, Bux, Faizal, and Kumari, Sheena
- Published
- 2024
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41. An exploratory study of social presence and cognitive engagement association in a collaborative virtual reality learning environment
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Dunmoye, Isaac D., Rukangu, Andrew, May, Dominik, and Das, Runu P.
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- 2024
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- View/download PDF
42. Yes, size does matter (for cycling safety)! Comparing behavioral and safety outcomes in S, M, L, and XL cities from 18 countries
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Useche, Sergio A., Alonso, Francisco, Boyko, Aleksey, Buyvol, Polina, Castañeda, Isaac D., Cendales, Boris, Cervantes, Arturo, Echiburu, Tomas, Faus, Mireia, Gene-Morales, Javier, Gnap, Jozef, Gonzalez, Victor, Ibrahim, Mohd K.A., Janstrup, Kira H., Makarova, Irina, Mikusova, Miroslava, Møller, Mette, O'Hern, Steve, Orozco-Fontalvo, Mauricio, Shubenkova, Ksenia, Siebert, Felix W., Soto, Jose J., Stephens, Amanda N., Wang, Yonggang, Willberg, Elias S., Wintersberger, Philipp, Zeuwts, Linus, Zulkipli, Zarir H., and McIlroy, Rich C.
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- 2024
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43. State of the California Current Ecosystem report in 2022: a tale of two La Niñas
- Author
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Andrew R. Thompson, Rasmus Swalethorp, Michaela Alksne, Jarrod A. Santora, Elliott L. Hazen, Andrew Leising, Erin Satterthwaite, William J. Sydeman, Clarissa R. Anderson, Toby D. Auth, Simone Baumann-Pickering, Timothy Baumgardner, Eric P. Bjorkstedt, Steven J. Bograd, Noelle M. Bowlin, Brian J. Burke, Elizabeth A. Daly, Heidi Dewar, John C. Field, Jennifer L. Fisher, Newell Garfield, Ashlyn Gidding, Ralf Goericke, Richard Golightly, Eliana Gómez-Ocampo, Jose Gomez-Valdes, John A. Hildebrand, Kym C. Jacobson, Michael G. Jacox, Jaime Jahncke, Michael Johns, Joshua M. Jones, Bertha Lavaniegos, Nate Mantua, Gerard J. McChesney, Megan E. Medina, Sharon R. Melin, Luis Erasmo Miranda, Cheryl A. Morgan, Catherine F. Nickels, Rachael A. Orben, Jessica M. Porquez, Antonella Preti, Roxanne R. Robertson, Daniel L. Rudnick, Keith M. Sakuma, Carley R. Schacter, Isaac D. Schroeder, Lauren Scopel, Owyn E. Snodgrass, Sarah Ann Thompson, Pete Warzybok, Katherine Whitaker, William Watson, Edward D. Weber, and Brian Wells
- Subjects
California Current ,marine heatwave ,La Niña/El Niño ,California Cooperative Oceanic Fisheries Investigation ,global warming ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
2022 marked the third consecutive La Niña and extended the longest consecutive stretch of negative Oceanic Niño Index since 1998-2001. While physical and biological conditions in winter and spring largely adhered to prior La Niña conditions, summer and fall were very different. Similar to past La Niña events, in winter and spring coastal upwelling was either average or above average, temperature average or below average, salinity generally above average. In summer and fall, however, upwelling and temperature were generally average or slightly below average, salinity was close to average and chlorophyll a was close to average. Again, as during prior La Niña events, biomass of northern/southern copepods was above/below average off Oregon in winter, and body size of North Pacific krill in northern California was above average in winter. By contrast, later in the year the abundance of northern krill dropped off Oregon while southern copepods increased and body sizes of North Pacific krill fell in northern California. Off Oregon and Washington abundances of market squid and Pacific pompano (indicators of warm, non-typical La Niña conditions) were high. In the 20th century, Northern anchovy recruitment tended to be high during cold conditions, but despite mostly warm conditions from 2015-2021 anchovy populations boomed and remained high in 2022. Resident seabird reproductive success, which tended in the past to increase during productive La Niña conditions was highly variable throughout the system as common murre and pelagic cormorant, experienced complete reproductive failure at Yaquina Head, Oregon while Brandt’s cormorant reproduction was average. At three sampling locations off central California, however, common murre reproduction was close to or above average while both pelagic and Brandt’s cormorant were above average. California sealion reproduction has been above average each year since 2016, and pup weight was also above average in 2022, likely in response not to La Niña or El Niño but continuous high abundance of anchovy. The highly variable and often unpredictable physical and biological conditions in 2022 highlight a growing recognition of disconnects between basin-scale indices and local conditions in the CCE. “July-December 2022 is the biggest outlier from individual “strong” La Niña (events) ever going back to the 50s.” – Nate Mantua
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- 2024
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44. An exploratory study of social presence and cognitive engagement association in a collaborative virtual reality learning environment
- Author
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Isaac D. Dunmoye, Andrew Rukangu, Dominik May, and Runu P. Das
- Subjects
Virtual reality (VR) learning environment ,Cognitive engagement ,Social presence ,Interactions ,Computer mediated communication (CMC) ,Education (General) ,L7-991 ,Information technology ,T58.5-58.64 - Abstract
As the utilization of virtual reality (VR) in engineering education increases, researchers are increasingly focused on enhancing teaching and learning within VR environments. Cognitive engagement among the participants is a fundamental outcome in any learning environment, where social interaction often plays a pivotal role. This study contributes to VR teaching and learning research by investigating the association between social presence indicators and modes of cognitive engagement in a desktop collaborative virtual reality (VR) learning environment based on the social presence theory and the cognitive engagement definition of the Interactive-Constructive-Active-Passive framework. The study participants logged into the VR platform to collaboratively solve simulated engineering statics problems. The transcripts of students' interaction videos were coded based on codebooks for both social presence and cognitive engagement. The study revealed that social presence indicators are significantly associated with the three modes of cognitive engagement (active, constructive, and interactive). Additionally, interactive open communication emerged as the primary social presence element utilized by students during cognitive engagement with peers in the learning environment. This study's findings have implications for research and practice in enhancing students' cognitive engagement through their social interactions within VR learning environment.
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- 2024
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- View/download PDF
45. Using Raman spectroscopy for early detection of resistance-breaking strains of tomato spotted wilt orthotospovirus in tomatoes
- Author
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Isaac D. Juárez, MacKenzi X. Steczkowski, Senthilraja Chinnaiah, Axell Rodriguez, Kiran R. Gadhave, and Dmitry Kurouski
- Subjects
tomato spotted wilt orthotospovirus ,Raman spectroscopy ,high performance liquid chromatography ,resistance breaking (RB) strains ,early detection ,orthotospovirus tomatomaculae ,Plant culture ,SB1-1110 - Abstract
Tomato spotted wilt (TSW) disease caused by tomato spotted wilt orthotospovirus (TSWV, Orthotospovirus tomatomaculae) poses a significant threat to specialty and staple crops worldwide by causing over a billion dollars in crop losses annually. Current strategies for TSWV diagnosis heavily rely on nucleic acid or protein-based techniques which require significant technical expertise, and are invasive, time-consuming, and expensive, thereby catalyzing the search for better alternatives. In this study, we explored the potential of Raman spectroscopy (RS) in early detection of TSW in a non-invasive and non-destructive manner. Specifically, we investigated whether RS could be used to detect strain specific TSW symptoms associated with four TSWV strains infecting three differentially resistant tomato cultivars. In the acquired spectra, we observed notable reductions in the intensity of vibrational peaks associated with carotenoids. Using high-performance liquid chromatography (HPLC), we confirmed that TSWV caused a substantial decrease in the concentration of lutein that was detected by RS. Finally, we demonstrated that Partial Least Squares-Discriminant Analysis (PLS-DA) could be used to differentiate strain-specific TSW symptoms across all tested cultivars. These results demonstrate that RS can be a promising solution for early diagnosis of TSW, enabling timely disease intervention and thereby mitigating crop losses inflicted by TSWV.
- Published
- 2024
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46. I Spy Transits and Pulsations: Empirical Variability in White Dwarfs Using Gaia and the Zwicky Transient Facility
- Author
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Guidry, Joseph A., Vanderbosch, Zachary P., Hermes, J. J., Barlow, Brad N., Lopez, Isaac D., Boudreaux, Emily M., Corcoran, Kyle A., Bell, Keaton J., Montgomery, M. H., Heintz, Tyler M., Castanheira, Barbara G., Reding, Joshua S., Dunlap, Bart H., Winget, D. E., Winget, Karen I., and Kuehne, J. W.
- Subjects
Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We present a novel method to detect variable astrophysical objects and transient phenomena using anomalous excess scatter in repeated measurements from public catalogs of Gaia DR2 and Zwicky Transient Facility (ZTF) DR3 photometry. We first provide a generalized, all-sky proxy for variability using only Gaia DR2 photometry, calibrated to white dwarf stars. To ensure more robust candidate detection, we further employ a method combining Gaia with ZTF photometry and alerts. To demonstrate the efficacy, we apply this latter technique to a sample of roughly $12,100$ white dwarfs within 200 pc centered on the ZZ Ceti instability strip, where hydrogen-atmosphere white dwarfs are known to pulsate. Through inspecting the top $1\%$ samples ranked by these methods, we demonstrate that both the Gaia-only and ZTF-informed techniques are highly effective at identifying known and new variable white dwarfs, which we verify using follow-up, high-speed photometry. We confirm variability in all 33 out of 33 ($100\%$) observed white dwarfs within our top $1\%$ highest-ranked candidates, both inside and outside the ZZ Ceti instability strip. In addition to dozens of new pulsating white dwarfs, we also identify five white dwarfs highly likely to show transiting planetary debris; if confirmed, these systems would more than triple the number of white dwarfs known to host transiting debris., Comment: 30 pages, 14 figures, revised and accepted to ApJ on March 11, 2021
- Published
- 2020
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47. Structural Prior Driven Regularized Deep Learning for Sonar Image Classification
- Author
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Gerg, Isaac D. and Monga, Vishal
- Subjects
Computer Science - Computer Vision and Pattern Recognition - Abstract
Deep learning has been recently shown to improve performance in the domain of synthetic aperture sonar (SAS) image classification. Given the constant resolution with range of a SAS, it is no surprise that deep learning techniques perform so well. Despite deep learning's recent success, there are still compelling open challenges in reducing the high false alarm rate and enabling success when training imagery is limited, which is a practical challenge that distinguishes the SAS classification problem from standard image classification set-ups where training imagery may be abundant. We address these challenges by exploiting prior knowledge that humans use to grasp the scene. These include unconscious elimination of the image speckle and localization of objects in the scene. We introduce a new deep learning architecture which incorporates these priors with the goal of improving automatic target recognition (ATR) from SAS imagery. Our proposal -- called SPDRDL, Structural Prior Driven Regularized Deep Learning -- incorporates the previously mentioned priors in a multi-task convolutional neural network (CNN) and requires no additional training data when compared to traditional SAS ATR methods. Two structural priors are enforced via regularization terms in the learning of the network: (1) structural similarity prior -- enhanced imagery (often through despeckling) aids human interpretation and is semantically similar to the original imagery and (2) structural scene context priors -- learned features ideally encapsulate target centering information; hence learning may be enhanced via a regularization that encourages fidelity against known ground truth target shifts (relative target position from scene center). Experiments on a challenging real-world dataset reveal that SPDRDL outperforms state-of-the-art deep learning and other competing methods for SAS image classification., Comment: To appear in TGRS, 2021
- Published
- 2020
48. WIDEFIELD SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS IN WAGNER SYNDROME
- Author
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Bleicher, Isaac D., Garg, Itika, Hoyek, Sandra, Place, Emily, Miller, John B., and Patel, Nimesh A.
- Published
- 2024
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- View/download PDF
49. State of the California Current 2019–2020: Back to the Future With Marine Heatwaves?
- Author
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Weber, Edward D, Auth, Toby D, Baumann-Pickering, Simone, Baumgartner, Timothy R, Bjorkstedt, Eric P, Bograd, Steven J, Burke, Brian J, Cadena-Ramírez, José L, Daly, Elizabeth A, de la Cruz, Martin, Dewar, Heidi, Field, John C, Fisher, Jennifer L, Giddings, Ashlyn, Goericke, Ralf, Gomez-Ocampo, Eliana, Gomez-Valdes, Jose, Hazen, Elliot L, Hildebrand, John, Horton, Cheryl A, Jacobson, Kym C, Jacox, Michael G, Jahncke, Jaime, Kahru, Mati, Kudela, Raphe M, Lavaniegos, Bertha E, Leising, Andrew, Melin, Sharon R, Miranda-Bojorquez, Luis Erasmo, Morgan, Cheryl A, Nickels, Catherine F, Orben, Rachael A, Porquez, Jessica M, Portner, Elan J, Robertson, Roxanne R, Rudnick, Daniel L, Sakuma, Keith M, Santora, Jarrod A, Schroeder, Isaac D, Snodgrass, Owyn E, Sydeman, William J, Thompson, Andrew R, Thompson, Sarah Ann, Trickey, Jennifer S, Villegas-Mendoza, Josue, Warzybok, Pete, Watson, William, and Zeman, Samantha M
- Subjects
Life Below Water ,California Current ,marine heat wave ,upwelling ,anchovy ,Ecosystem Assessment ,CalCOFI ,Oceanography ,Ecology - Abstract
The California Current System (CCS) has experienced large fluctuations in environmental conditions in recent years that have dramatically affected the biological community. Here we synthesize remotely sensed, hydrographic, and biological survey data from throughout the CCS in 2019–2020 to evaluate how recent changes in environmental conditions have affected community dynamics at multiple trophic levels. A marine heatwave formed in the north Pacific in 2019 and reached the second greatest area ever recorded by the end of summer 2020. However, high atmospheric pressure in early 2020 drove relatively strong Ekman-driven coastal upwelling in the northern portion of the CCS and warm temperature anomalies remained far offshore. Upwelling and cooler temperatures in the northern CCS created relatively productive conditions in which the biomass of lipid-rich copepod species increased, adult krill size increased, and several seabird species experienced positive reproductive success. Despite these conditions, the composition of the fish community in the northern CCS remained a mixture of both warm- and cool-water-associated species. In the southern CCS, ocean temperatures remained above average for the seventh consecutive year. Abundances of juvenile fish species associated with productive conditions were relatively low, and the ichthyoplankton community was dominated by a mixture of oceanic warm-water and cosmopolitan species. Seabird species associated with warm water also occurred at greater densities than cool-water species in the southern CCS. The population of northern anchovy, which has been resurgent since 2017, continued to provide an important forage base for piscivorous fishes, offshore colonies of seabirds, and marine mammals throughout the CCS. Coastal upwelling in the north, and a longer-term trend in warming in the south, appeared to be controlling the community to a much greater extent than the marine heatwave itself.
- Published
- 2021
50. Grandiosity
- Author
-
Balbus, Isaac D., primary
- Published
- 2023
- Full Text
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