Atlantic Region Research Articles

Transcriptome Signatures of Atlantic Salmon-Resistant Phenotypes against Sea Lice Infestation Are Associated with Tissue Repair.

Salmon aquaculture is constantly threatened by pathogens that impact fish health, welfare, and productivity, including the sea louse Caligus rogercresseyi. This marine ectoparasite is mainly controlled through delousing drug treatments that have lost efficacy. Therein, strategies such as salmon breeding selection represent a sustainable alternative to produce fish with resistance to sea lice. This study explored the whole-transcriptome changes in Atlantic salmon families with contrasting resistance phenotypes against lice infestation. In total, 121 Atlantic salmon families were challenged with 35 copepodites per fish and ranked after 14 infestation days. Skin and head kidney tissue from the top two lowest (R) and highest (S) infested families were sequenced by the Illumina platform. Genome-scale transcriptome analysis showed different expression profiles between the phenotypes. Significant differences in chromosome modulation between the R and S families were observed in skin tissue. Notably, the upregulation of genes associated with tissue repairs, such as collagen and myosin, was found in R families. Furthermore, skin tissue of resistant families showed the highest number of genes associated with molecular functions such as ion binding, transferase, and cytokine activity, compared with the susceptible. Interestingly, lncRNAs differentially modulated in the R/S families are located near genes associated with immune response, which are upregulated in the R family. Finally, SNPs variations were identified in both salmon families, where the resistant ones showed the highest number of SNPs variations. Remarkably, among the genes with SPNs, genes associated with the tissue repair process were identified. This study reported Atlantic salmon chromosome regions exclusively expressed in R or S Atlantic salmon families' phenotypes. Furthermore, due to the presence of SNPs and high expression of tissue repair genes in the resistant families, it is possible to suggest mucosal immune activation associated with the Atlantic salmon resistance to sea louse infestation.

A Multidecadal Assessment of Mean and Extreme Wave Climate Observed at Buoys off the U.S. East, Gulf, and West Coasts

The current understanding of wind-generated wave climate from buoy-based measurements is mainly focused on a limited number of locations and has not been updated to include measurements in the past decade. This study quantifies wave climate variability and change during the historical period of 1980–2020 through a comprehensive analysis of wave height measurements at 43 buoys off the U.S. Pacific, Atlantic, and Gulf of Mexico Coasts. Variabilities and trends in the annual and monthly mean and 95th percentile significant wave heights (SWH) and the number of extreme wave events are quantified for the cold and warm seasons. We calculate the SWH long-term and decadal trends, and temporal variabilities using the ordinary least squares regression and coefficient of variation, respectively. Independent extreme wave events are identified using a method based on the peaks-over-threshold and the autocorrelation function, which accounts for the geographical variation in the timespan between independent extreme events. Results show that the warm season’s interannual variabilities in monthly and annual SWH are smaller in the Pacific while larger in the Atlantic and Gulf, with the largest variabilities observed at buoys in the Gulf and lower latitudes of the Atlantic. Strong significant alternating decadal trends in SWH are found in the Pacific and Atlantic regions. Buoys in the Atlantic and Gulf regions have experienced higher numbers of extreme wave events (anomalies) compared to the Pacific region. In general, the long-term trend in the number of extreme events during the cold season is positive at buoys located at higher latitudes but negative at lower latitudes.

Unzipping supercontinent Pangea: Geologic, potential field data, and buried structures, and a case for sequential Atlantic opening

Amalgamation of Pangea culminated with zippered N-to-S closing of the Theic ocean during the Alleghanian orogeny. Transpressional-rotational collision produced widespread dextral faulting throughout the eastern Appalachian hinterland, and thrust faulting in the western hinterland and foreland. The partially buried southern Appalachian Eastern Piedmont fault system is a product of late Paleozoic transpressional dextral faulting. Eastern Piedmont fault system faults are cut by two 200–190 Ma Central Atlantic Magmatic Province (CAMP) diabase dike sets (∼NW and NS), which postdate initial rifting, producing the Late Triassic-Early Jurassic basins. Sinistral reactivation of suitably oriented Paleozoic faults (e.g., Towaliga) that offset Jurassic dikes implies faulting is coeval with CAMP dike emplacement, or occurred very soon after 200–190 Ma dike emplacement. A large NE-striking sinistral fault (Estill fault) offsets magnetic and gravity highs in the Brunswick (Charleston) terrane in South Carolina and Georgia. This fault is at least 185 km long, with ca. 75–80 km maximum of sinistral separation. The Estill fault geometry agrees with the stress field associated with Central Atlantic Magmatic Province dike emplacement. We conclude that movement along the Estill and other sinistral faults represents Early Jurassic displacement that is well documented in eastern North America prior to Atlantic opening. The early Mesozoic post-failed rifting (basin formation) preceded dike emplacement and pre-spreading sinistral faulting. We recognize four stages in the Late Triassic–Jurassic tectonics and kinematics of eastern North America based on field, crosscutting relationships, and available geophysical data: (1) initial W-to-E failed transtensional rifting with formation of the S-to-N-younging Triassic-Jurassic basins; (2) CAMP diabase dikes intruded 200–190 Ma; (3) sinistral movement of large blocks of crust in the North Atlantic region including southeastern North America; and (4) spreading and opening of the Atlantic Ocean 195–170 Ma. These stages mark the reversal of Alleghanian rotational dextral transpressional (zippered) collision forming Pangea supercontinent and ‘unzipping’ the supercontinent prior to Atlantic opening.

Seismically-derived porosity of deep-sea sediments over the last 74 Ma in the equatorial Atlantic Ocean: Implications for paleo-climate

Deep-sea sediments record the geological and climate history of the Earth. The seismic properties of these sediments, namely the P- and S-wave velocities, depend on their chemical compositions, grain size, age and depth of burial, which, in turn, influence the porosity. We use multichannel seismic reflection data to estimate the sediment thickness and P-wave velocity over 4-74 Ma old oceanic crust on the African Plate and 3-27 Ma old crust on the South American Plate in the equatorial Atlantic Region. We then use the P-to-S converted waves from the basement-sediment interface recorded by 69 multi-component ocean bottom seismometers to determine the P- and S-wave velocity ratios (VPVS) over 3 to 74 Ma. We find that the VPVS decreases from 8.9 ± 2.0 at 3 Ma to 5.0 ± 1.0 at 17 Ma but abruptly increases to 19.5 ± 2.8 at 37.5 Ma. Then, it gradually decreases for crustal ages >37 Ma, reaching 7.0 ± 0.3 at 74 Ma. These variations are almost symmetric across the Mid-Atlantic Ridge over 4-27 Ma, suggesting a relation to climate change rather than regional effects. We estimate the average sediment porosity using the VPVS and find that the average porosity decreases from 89.2 ± 1.5% at 37.5 Ma to 69.9 ± 1.2% at 74 Ma, possibly associated with accumulation of terrigenous input from Africa. Between 4 and 37 Ma, the porosity fluctuates between 70% and 85%. Such a fluctuation correlates well with the decrease in the global atmospheric CO2 from 800 ppm to 400 ppm during the Oligocene and with carbonate compensation depth, which are possibly related to fauna/flora diversification and calcareous sediment accumulation. The variation in porosity at 23 and 17 Ma also appears to be linked with major climate shifts, suggesting that sediment porosity could be used to shed light on the past climate and fauna/flora characterization.

Iceland and China: Strategic Partnership in the Arctic and Euro-Atlantic

The article analyses the development of China-Iceland relations which led to a full-scale political and economic partnership between the two countries, the current issues in Chinese policies towards Iceland, its plans to use the island as a starting point for expansion in Europe, Atlantic and Arctic regions. The paper explores the interests of the two states, stages of development of their relations, recent development with China's return to Iceland after three years of the pandemic, and Chinese intentions to enhance the partnership in order to extend its influence in Arctics and Euro-Atlantics. This analysis sheds light on the Chinese policy in the Arctic which is important for the future of Russo-Chinese relations in the region, and on how the Chinese entrenchment in Northern Europe may change the balance of power and interest not only in the Arctic, but in the Euro-Atlantic region. The article reveals that China, as a non-Arctic state, is striving to intensify cooperation with Iceland, but the relations in recent years have begun to sour both due to the pressure from the United States and the EU, as well as pandemic restrictions. Despite Iceland's tense relations with the European partners and the United States and the active assistance of China, in the future Iceland may be inclined to choose the United States as a strategic partner.

Spatial variation in the association between agricultural activities and bird communities in Canada

Agriculture is one the main drivers of bird decline in both Europe and North America. While it is clear that agricultural practices and changes in the rural landscape directly and indirectly affect bird communities, we still do not know the extent to which these impacts might change across broad spatial and temporal scales. To address this question, we combined information on agricultural activities with occurrence and abundance of 358 bird species across five time periods spanning 20 years in Canada. As a proxy for agricultural impact, we used a combined index that included different agricultural metrics, such as cropland and tillage area and area treated with pesticides. We found that agriculture impact was negatively associated with bird diversity and evenness across all 20 years studied, but these associations seemed to vary by region. We found good support for an overall negative association between agriculture impact and bird diversity and evenness in the Eastern and Atlantic regions but weaker associations in the Prairies and Pacific. These findings suggest that agricultural activities result in bird communities that are less diverse and disproportionately benefit certain species. The spatial variation in the impact of agriculture on bird diversity and evenness we observed is likely a result of regional differences in the native vegetation, the type of crops and commodities produced, the historical context of agriculture, as well as the native bird community and the extent of their association with open habitat. Thus, our work provides support for the idea that the on-going agricultural impact on bird communities, while largely negative, is not uniform, and can vary across broad geographic regions.

Assessing growth of pelagic sargassum in the Tropical Atlantic

Pelagic sargassum species, historically endemic to the North Atlantic, have now been identified in the Tropical Atlantic. For over a decade, massive blooms of pelagic sargassum have dispersed seasonally from this ‘new’ Tropical Atlantic source region, negatively impacting the coasts of Caribbean and West African countries. Significant strides have been made towards adaptation to this new ‘hazard’, yet many knowledge gaps remain that constrain improvements to these efforts. The key objective of this study was to add to the knowledge of pelagic sargassum growth rates in the Tropical Atlantic to better inform forecasting and innovative applications. Growth rates of the three commonly occurring morphotypes from the Tropical Atlantic source region, S. fluitans III, S. natans I and S. natans VIII, were studied in-situ using novel 'growth mesocosms' in neritic waters of Barbados under cool and warm ambient conditions. Overall, results reveal a significant difference in growth rates among all pelagic sargassum morphotypes, with S. fluitans III on average doubling its biomass in 13 days, S. natans I in 22 days and S. natans VIII in 31 days. Furthermore, growth rates of S. fluitans III decreased significantly with an increase in ambient temperature from the cool (mean 27.6 °C) to warm (mean 29.6 °C) water period. During both periods S. fluitans III grew significantly faster than the other two morphotypes. However, S. natans I only grew significantly faster than its conspecific morphotype, S. natans VIII, during the cool period. These findings highlight the different growth responses among sargassum morphotypes under varying conditions and add to the considerable variability in growth rates reported by recent similar studies conducted elsewhere in the Tropical Atlantic. As such, it is clear that further research will be needed to unravel the complex mechanisms affecting pelagic sargassum growth rates before they can confidently inform improvements in management applications.

Visible or not? Reflection of the 8.2 ka BP event and the Greenlandian–Northgrippian boundary in a new high-resolution pollen record from the varved sediments of Lake Mondsee, Austria

This paper presents a new pollen record from Lake Mondsee in the north-eastern European Alps and discusses changes in vegetation composition between 9000 and 7000 a BP in response to the 8.2 ka BP cooling event, which is clearly reflected in a stable oxygen isotope record from the same lake. Pollen and microcharcoal analyses performed at bi-decadal resolution provide detailed insights into the vegetation history and fire regime in the study area. The late Greenlandian and early Northgrippian between ca. 9000 and 8000 a BP were mainly characterised by the gradual expansion of spruce, accompanied by the retreat of hazel. Results of the pollen-based biome reconstruction show that the Greenlandian–Northgrippian boundary at ca. 8280 a BP was marked by a shift in the affinity scores of regional forest biomes, reflecting a decreasing role of temperate broadleaved trees and shrubs and a strengthening of boreal conifers in the study area. During the early Northgrippian between ca. 8000 and 7000 a BP, fir and beech spread around Lake Mondsee, which is in line with other pollen records from the northern Alpine Foreland, indicating cooler and moister conditions. This long-term trend is likely a response to decreasing summer insolation (i.e. decreasing summer temperatures) and the weakening of the Siberian High, which promoted westerly-driven moisture transport from the Atlantic region. Visual inspection of the Lake Mondsee pollen data does not reveal a clear signal of the 8.2 ka BP event. However, biomization results show a distinct minimum in the temperate deciduous biome scores and summed scores of plant functional types representing warm-loving tree and shrub taxa at ca. 8165–8135 a BP.

Evidence of Arctic methane emissions across the mid-Pleistocene

During the Pleistocene, Earth’s climate changed dramatically. The mid-Pleistocene transition (MPT; ~1.3–0.7 million years (Ma)) featured an important ice volume increase at both poles. The evolution of large Arctic ice sheets caused the sequestration of methane as free gas and hydrates in subseabed sediments. Ice volume changes, associated with variable pressures and temperatures, perturbed those giant reservoirs, causing methane leakages. Here, we present borehole data from the Arctic–Atlantic gateway region, providing foraminiferal stable carbon isotope and source-specific biomarker evidence that reveals three main seafloor leakage episodes that occurred prior to and across the mid-Pleistocene transition. By combining borehole data with hydrate stability modelling, we propose that tectonic stress changes associated with large ice volume early build-up and wastage during the mid-Pleistocene controlled episodic methane leakages from subsurface reservoirs. Our data indicate methane release, showing a potential scenario for vast Arctic areas storing methane that are now affected by ongoing ice volume decrease.

Natal Origin and Spatiotemporal Distribution of Leatherback Turtle (Dermochelys coriacea) Strandings at a Foraging Hotspot in Temperate Waters of the Southwest Atlantic Ocean.

Leatherback turtles migrate long distances between nesting beaches and distant foraging areas worldwide. This study analyzes the genetic diversity, life history stage, spatiotemporal distribution, and associated threats of a foraging aggregation in the Southwest Atlantic Ocean. A total of 242 leatherbacks stranded or bycaught by artisanal fisheries were recorded from 1997 to 2021 in Uruguay, with sizes ranging from 110.0 to 170.0 cm carapace lengths, indicating that the aggregation is composed of large juveniles and adults. Results of Bayesian mixed-stock analysis show that leatherbacks come primarily from the West African rookeries, based on mitochondrial DNA sequences obtained from 59 of the turtles representing seven haplotypes, including a novel one (Dc1.7). The main threat identified in the area is the fisheries bycatch but most of the carcasses observed were badly decomposed. There was significant seasonal and interannual variability in strandings that is likely associated with the availability of prey and the intensity of the fishing effort. Taken together, these findings reinforce the importance of these South American foraging areas for leatherbacks and the need to determine regional habitat use and migratory routes across the broader Atlantic region, in order to develop effective conservation measures to mitigate threats both at nesting beaches and foraging areas.

High Resolution Estimation of Ocean Dissolved Inorganic Carbon, Total Alkalinity and pH Based on Deep Learning

This study combines measurements of dissolved inorganic carbon (DIC), total alkalinity (TA), pH, earth observation (EO), and ocean model products with deep learning to provide a good step forward in detecting changes in the ocean carbonate system parameters at a high spatial and temporal resolution in the North Atlantic region (Long. −61.00° to −50.04° W; Lat. 24.99° to 34.96° N). The in situ reference dataset that was used for this study provided discrete underway measurements of DIC, TA, and pH collected by M/V Equinox in the North Atlantic Ocean. A unique list of co-temporal and co-located global daily environmental drivers derived from independent sources (using satellite remote sensing, model reanalyses, empirical algorithms, and depth soundings) were collected for this study at the highest possible spatial resolution (0.04° × 0.04°). The resulting ANN-estimated DIC, TA, and pH obtained by deep learning shows a high correspondence when verified against observations. This study demonstrates how a select number of geophysical information derived from EO and model reanalysis data can be used to estimate and understand the spatiotemporal variability of the oceanic carbonate system at a high spatiotemporal resolution. Further methodological improvements are being suggested.

Riparian forest response to extreme drought is influenced by climatic context and canopy structure

Droughts significantly impact forest ecosystems, reducing forest health and productivity, compromising ecosystem functioning, and nature-based solutions for climate change. The response and resilience of riparian forests to drought are poorly understood despite their key role in the functioning of aquatic and terrestrial ecosystems. Here we investigate riparian forest drought responses and resilience to an extreme drought event at a regional scale. We also examine how drought event characteristics, average climate conditions, topography, soil, vegetation structure, and functional diversity shape the resilience of riparian forests to drought. We used a time series of the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) to calculate the resistance to and recovery after an extreme drought (2017–2018) in 49 sites across an Atlantic-Mediterranean climate gradient in North Portugal. We used generalized additive models and multi-model inference to understand which factors best explained drought responses. We found a trade-off between drought resistance and recovery (maximum r = −0.5) and contrasting strategies across the climatic gradient of the study area. Riparian forests in the Atlantic regions showed comparatively higher resistance, while Mediterranean forests recovered more. Canopy structure and climate context were the most relevant predictors of resistance and recovery. However, median NDVI and NDWI had not returned to pre-drought levels (RcNDWI mean = 1.21, RcNDVI mean = 1.01) three years after the event. Our study shows that riparian forests have contrasting drought response strategies and may be susceptible to extended legacy effects associated with extreme and/or recurring droughts, similarly to upland forests. This work highlights the drought vulnerability of riparian ecosystems and emphasises the need for further studies on long-term resilience to droughts.

Abstract 746: Disparities in factors affecting access to palliative care in patients with stage IV breast cancer

Abstract Background: Palliative care is an essential component of cancer care; however, factors hindering its reach to the target population remain understudied. We aim to explore whether an association exists between socioeconomic and geographic factors and access to palliative care (PC) in patients with Stage IV breast cancer in the US. Methods: This 2004-2017 National Cancer Database analysis includes patients with Stage IV breast cancer who received palliative care. Access to PC is defined as being either at the patient’s primary healthcare facility or at a referral site. Chi-square tests and a multivariate logistic regression were performed to determine the independent factors predicting access to PC. SAS version 9.4 was used to analyze the data. Results: A total of 18,903 patients were included in the analysis: 15,111 received palliative care services at the same facility and 3,792 were referred elsewhere. Patient age, race, insurance status, Charlson-Deyo score, setting, high school diploma status, median income, facility type, facility location, and distance from healthcare centers were all significantly different between the two groups. On logistic regression, better odds for access to PC were predicted by urban settings (OR: 1.47; 95% CI: 1.30 - 1.67) and being in the Middle Atlantic region (OR: 1.27; 95% CI: 1.07 - 1.52). Distance from the healthcare facility of 4 miles or greater predicted worse odds for access to PC. Comprehensive cancer programs (OR: 1.60; 95% CI: 1.43 - 1.80) and academic/research programs (OR: 2.40; 95% CI: 2.11 - 2.73) held higher odds for access to PC. Having Medicaid/other government insurance (OR: 1.43; 95% CI: 1.24 - 1.65) predicted better odds for access to PC. However, having no insurance was also found to increase access to PC (OR: 1.30; 95% CI: 1.08 - 1.55). Median income and high school diploma status were not significantly associated with the outcome. Conclusion: PC was positively affected by having access to urban settings, nearby healthcare centers, non-community care centers, Medicaid/other governmental insurance, and by being in the Middle Atlantic region of the US. Having no insurance appears to increase palliative care use, which was unexpected but could be explained if patients with no insurance did not receive standard treatment and were instead offered palliative care. This needs to be investigated in future research. Citation Format: Mira Itani, Saad Sabbagh, Mohamed Mohanna, Barbara Dominguez, Hong Liang, Zeina Nahleh. Disparities in factors affecting access to palliative care in patients with stage IV breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 746.

New species and records of Heterospio (Annelida, Longosomatidae) from continental shelf, slope and abyssal depths of the Atlantic Ocean, Pacific Ocean, Indian Ocean and adjacent seas.

Nineteen species of the rare polychaete genus Heterospio are reported, 15 of which are new to science. The status of H. longissima Ehlers, 1874, the type-species, is reviewed. The specimens examined are from several locations in the North Atlantic Ocean, Gulf of Mexico, Caribbean Sea, off Br azil, the Indian Ocean, the Pacific Ocean off California, New Zealand, Australia, and the South China Sea. Deep-water samples from the western North Atlantic Ocean collected by the late Drs. H.L. Sanders and R.R. Hessler that were reported by Hartman as H. longissima were re-examined and referred to two new species, H. hartmanae n. sp. (abyssal depths, New England to Bermuda transect) and H. guiana n. sp. (bathyal depths off Suriname). Other materials from the Sanders/Hessler North Atlantic collections were also examined and referred to two additional species, H. canariensis n. sp. (deep water off Canary Islands) and H. southwardorum n. sp. (Bay of Biscay) as well as H. cf. reducta from off SW Ireland in bathyal depths. New collections from the North Atlantic region include additional materials of H. hartmanae n. sp. (deep water off the Mid-Atlantic and SE USA), H. aruba n. sp. (Caribbean Sea), H. bathyala n. sp. (deep water off SE USA), and H. dibranchiata n. sp. (deep water, Gulf of Mexico). Heterospio paulolanai n. sp. is from shelf depths off southeastern Brazil. Heterospio knoxi n. sp. is from the North Island of New Zealand, H. ehlersi n. sp. is from the Gulf of Thailand, in the South China Sea, H. bidentata n. sp. is described from deep water in the Coral Sea off eastern Australia, and H. alata n. sp. and H. brunei n. sp. are described from deep water off the Island of Borneo in the South China Sea. Heterospio africana n. sp. and H. antonbruunae n. sp. are described from off east Africa in the Mozambique Channel. New records and descriptions of H. catalinensis, H. indica, and H. peruana are presented. The 15 new species reported here nearly triple the number of previously known species of Heterospio, with 23 species now recognized. All known species are tabulated and compared.

The Role of Atmospheric Noise in Decadal SST Variability

Abstract A substantial role for atmospheric noise in simulations of decadal internal variability of SST is demonstrated by a comparison of a multicentury climate model control and a corresponding interactive ensemble (IE) simulation. The IE is designed to reduce atmospheric noise in the heat flux, wind stress, and freshwater flux at the air–sea interface. This comparison suggests that nearly all SST variability on decadal time scales is forced by internal atmospheric variability. The results are examined to determine the relative roles of atmospheric surface heat flux noise and ocean dynamics in the decadal volume-averaged heat budget of the upper ocean. The regional heat budgets in two regions, the South Pacific and the midlatitude North Atlantic, show the net atmospheric surface heat flux to be approximately in equilibrium with the ocean dynamics forcing. The IE and control results are used in the equilibrium heat budget approximation to infer the atmospheric heat flux response to SST, as well as the time series of the control atmospheric noise surface heat flux and ocean dynamics forcings for several regions. The South Pacific region SST is found to be primarily forced by the atmospheric noise surface heat flux and the North Atlantic region SST is forced by the ocean dynamics. Similar strengths for the atmospheric heat flux noise and ocean dynamics forcing, with an interdecadal atmospheric heat flux noise time scale and a centennial ocean dynamics time scale, are found for an Atlantic multidecadal variability region SST.

Role of multi-decadal variability of the winter North Atlantic Oscillation on Northern Hemisphere climate

The North Atlantic Oscillation (NAO) plays a leading role in modulating wintertime climate over the North Atlantic and the surrounding continents of Europe and North America. Here we show that the observed evolution of the NAO displays larger multi-decadal variability than that simulated by nearly all CMIP6 models. To investigate the role of the NAO as a pacemaker of multi-decadal climate variability, we analyse simulations that are constrained to follow the observed NAO. We use a particle filter data-assimilation technique that sub-selects members that follow the observed NAO among an ensemble of simulations, as well as the El Niño Southern Oscillation and Southern Annular Mode in a global climate model, without the use of nudging terms. Since the climate model also contains external forcings, these simulations can be used to compare the simulated forced response to the effect of the three assimilated modes. Concentrating on the 28 year periods of strongest observed NAO trends, we show that NAO variability leads to large multi-decadal trends in temperature and precipitation over Northern Hemisphere land as well as in sea-ice concentration. The Atlantic subpolar gyre region is particularly strongly influenced by the NAO, with links found to both concurrent atmospheric variability and to the Atlantic Meridional Overturning Circulation (AMOC). Care thus needs to be taken to account for impacts of the NAO when using sea surface temperature in this region as a proxy for AMOC strength over decadal to multi-decadal time-scales. Our results have important implications for climate analyses of the North Atlantic region and highlight the need for further work to understand the causes of multi-decadal NAO variability.

Seasonal and interannual variation of equatorial waves in ERA5 and GloSea5

AbstractThis study presents an analysis of the equatorial waves in the ERA5 reanalysis and forecasts of the Met Office Global Seasonal Forecast System version 5 (GloSea5), by projecting dynamical fields onto theoretical equatorial wave modes. The seasonal and interannual variation of equatorial wave activity in GloSea5 is evaluated against ERA5 waves. We find that in ERA5 the seasonal and spatial variations of eastward‐moving Kelvin wave activity are mainly determined by the ambient zonal flow, with wave activity being stronger in easterlies than westerlies. For the westward‐moving mixed Rossby–gravity waves and equatorial Rossby waves, the seasonal and spatial variations of the upper‐tropospheric wave activity are determined by both the ambient flow and extratropical forcing with stronger wave activity generally in the westerlies, whilst the lower‐tropospheric wave activity is related to the ambient flow and tropical convection. In GloSea5, the Kelvin wave activity is not well simulated in the upper troposphere, and in general the wave activity and wave‐related convective signal are too weak. In contrast, GloSea5 performs better for the westward‐moving equatorial waves, including their Doppler‐shifted eastward‐moving components, despite a significant overestimation in the Atlantic and African region. The phase of ENSO has a substantial impact on equatorial waves in both ERA5 and GloSea5. The mechanism of the impact is through changes in the ENSO‐related ambient flow, upper‐tropospheric extratropical forcing, and tropical convection. GloSea5 can capture the low‐level Kelvin wave–ENSO relationship reasonably well, with stronger wave activity over the eastern Pacific in El Niño, although the ENSO‐driven variation is too weak. The wave–ENSO relationship for westward‐moving waves is well represented in GloSea5, especially in the upper‐level eastern‐Pacific westerly duct region in the extended boreal winter and the low‐level Indo‐Pacific in all seasons. We conclude that in GloSea5 the representation of the wave–ENSO teleconnection is the key driver for the performance of interannual variability in the wave activity.

MP47-03 TRENDS IN SBRT FOR INOPERABLE RENAL CELL CARCINOMA

You have accessJournal of UrologyCME1 Apr 2023MP47-03 TRENDS IN SBRT FOR INOPERABLE RENAL CELL CARCINOMA Benjamin V. Stone, David-Dan Nguyen, Dejan K. Filipas, Muhieddine Labban, Edoardo Beatrici, Alexander P. Cole, Shawn Malone, Christopher J. D. Wallis, Quoc-Dien Trinh, Scott C. Morgan, and Soumyajit Roy Benjamin V. StoneBenjamin V. Stone More articles by this author , David-Dan NguyenDavid-Dan Nguyen More articles by this author , Dejan K. FilipasDejan K. Filipas More articles by this author , Muhieddine Labban Muhieddine Labban More articles by this author , Edoardo BeatriciEdoardo Beatrici More articles by this author , Alexander P. ColeAlexander P. Cole More articles by this author , Shawn MaloneShawn Malone More articles by this author , Christopher J. D. WallisChristopher J. D. Wallis More articles by this author , Quoc-Dien TrinhQuoc-Dien Trinh More articles by this author , Scott C. MorganScott C. Morgan More articles by this author , and Soumyajit RoySoumyajit Roy More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003293.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: A growing body of evidence suggests that stereotactic body radiotherapy (SBRT) could be an appropriate local treatment strategy for patients with renal cell carcinoma (RCC) who refuse surgery or are medically inoperable, but the degree of uptake of SBRT remains understudied. METHODS: The National Cancer Database was utilized to identify all patients from 2004-2020 with non-metastatic RCC for whom surgery was not performed due to medical comorbidities, age, locally advanced disease, or patient refusal. We evaluated trends over time in the use of radiation to the primary tumor for these patients, and the modality of radiation used. Multivariable logistic regression was used to determine the predictors of SBRT adjusted for baseline demographic and clinical covariates. We used multivariable Cox regression to determine the adjusted association of SBRT with overall survival (OS). RESULTS: There were 10,810 patients with RCC from 2004-2020 who were deemed poor surgical candidates or refused surgery. The proportion receiving radiation to the primary tumor increased from 1.7% from 2004-2009 to 3.3% in 2020 (p=0.02), and the proportion treated with SBRT vs. EBRT increased from 51% in 2004-2009 to 65% in 2020. There was a small but statistically significant increase in the odds of SBRT over time (OR=1.05, 95% CI 1.01-1.09, p=0.008 for each year of diagnosis). Age 70-79, treatment at a non-academic center, treatment in New England (versus Atlantic region) and VA insurance were associated with use of SBRT, while cT2 disease was associated with lower use of SBRT versus cT1 disease (Table 1). SBRT (HR 0.52, 95% CI 0.39-0.71, p<0.001) was associated with a significant OS benefit on multivariable Cox regression analysis adjusted for age, race, ethnicity, treatment setting, cT stage, cN stage, histology, and systemic treatment (Table 2). CONCLUSIONS: Although overall utilization of SBRT is very low in RCC patients who are poor candidates for surgery or who refuse surgery, there seems to be an increasing trend of utilization over time. Use of SBRT was associated with superior OS compared to patients treated with EBRT. Source of Funding: N/A © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e643 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Benjamin V. Stone More articles by this author David-Dan Nguyen More articles by this author Dejan K. Filipas More articles by this author Muhieddine Labban More articles by this author Edoardo Beatrici More articles by this author Alexander P. Cole More articles by this author Shawn Malone More articles by this author Christopher J. D. Wallis More articles by this author Quoc-Dien Trinh More articles by this author Scott C. Morgan More articles by this author Soumyajit Roy More articles by this author Expand All Advertisement PDF downloadLoading ...

Trends in Private Equity Acquisitions of USOtolaryngology Practices.

With the increasing consolidation of physician practices, private equity (PE) firms have been playing a growing role in healthcare delivery and recently began entering the otolaryngology-head and neck surgery space. To date, no studies have examined the extent of PE investment in otolaryngology. We assessed trends and geographic distribution of USotolaryngology practices acquired by PE using Pitchbook (Seattle, WA), a comprehensive market database. From 2015 to 2021, 23 otolaryngology practices were acquired by PE. The number of PE acquisitions increased over time: 1 practice was acquired in 2015 versus4 practices in 2019 versus 8 practices in 2021. Nearly half (43.5%, n = 10) of acquired practices were in the South Atlantic region. The median number of otolaryngologists at these practices was 5 (interquartile range: 3-7). As PE investment in otolaryngology continues to grow, further research is needed to assess its impact on clinical decision-making, healthcare costs, physician job satisfaction, clinical efficiency, and patient outcomes.

Livestock haulers' views about dairy cattle transport in Atlantic Canada

Surplus dairy calves and cull cows are often transported from the dairy farm to a variety of destinations and may experience compromised health and welfare in the process. Increasing interest in farm animal welfare by many stakeholders, including the public and policymakers, has brought about recent changes to livestock transport regulations in Canada that have likely affected transport operations across the country. The Atlantic region may be especially affected as a result of a smaller number of farms, and geography that often requires cattle to be transported long distances. We interviewed 7 livestock haulers in Atlantic Canada regarding their attitudes toward the recent changes to the transport regulations, particularly with regard to how these changes affected their business practices and dairy cattle welfare, as certain regulatory changes pertaining to calf transport were expected to disrupt existing transport practices. Thematic analysis of interview transcripts revealed 2 themes among participants: (1) calf (and sometimes adult cow) welfare and management during transport and on the dairy farm, and (2) feasibility of transport requirements and the enforcement of the regulations, including animosity toward other haulers and the challenge of satisfying both regulatory bodies and farmer clientele. These findings provide insight into the perspectives of an important, and often overlooked, stakeholder in the dairy industry on the transport system and highlight the need for inclusion of diverse voices when creating new policy.