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Deposition of continental mineral aerosols (dust) in the Eastern Tropical North Atlantic Ocean, between the coast of Africa and the Mid-Atlantic Ridge, was estimated using several strategies based on the measurement of aerosols, trace metals dissolved in seawater, particulate material filtered from the water column, particles collected by sediment traps and sediments. Most of the data used in this synthesis involve samples collected during US GEOTRACES expeditions in 2010 and 2011, although some results from the literature are also used. Dust deposition generated by a global model serves as a reference against which the results from each observational strategy are compared. Observation-based dust fluxes disagree with one another by as much as two orders of magnitude, although most of the methods produce results that are consistent with the reference model to within a factor of 5. The large range of estimates indicates that further work is needed to reduce uncertainties associated with each method before it can be applied routinely to map dust deposition to the ocean. Calculated dust deposition using observational strategies thought to have the smallest uncertainties is lower than the reference model by a factor of 2-5, suggesting that the model may overestimate dust deposition in our study area.This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'.

Background: The Fire service Organizational Culture of Safety (FOCUS) survey is an assessment tool comprised of psychometrically validated metrics of safety climate, safety behavior, and downstream outcomes (organizational and injury) that are specific to the U.S. fire and rescue service., Methods: This analysis consists of a descriptive summary of two independent survey waves (FOCUS 1.0 and 2.0). The fire departments included in these survey waves were from convenience sampling (n 1.0  = 275; n 2.0  = 170). In addition to department level characteristics, we examined individual level characteristics for firefighters and EMS providers in participating departments (n 1.0  = 22,719; n 2.0  = 16,882). We conducted regression analyses to examine the associations between safety climate and safety behaviors, organizational outcomes, and safety outcomes. All analyses were stratified by organization type (career, volunteer)., Results: Our analysis indicated that a majority of respondents were males (90.7% FOCUS 1.0 ; 90.4% FOCUS 2.0 ), non-officers (68.4% FOCUS 1.0 ; 66.4% FOCUS 2.0 ), and non-Hispanic Whites (70.8% FOCUS 1.0 ; 69.5% FOCUS 2.0 ). For both samples there was a higher prevalence of injuries among individuals in career departments (n FOCUS 1.0  = 3778 [17.5%]; n FOCUS 2.0  = 3072 [18.7%]) than volunteer departments (n FOCUS 1.0  = 103 [8.8%]; n FOCUS 2.0  = 34 [7.4%]). We observed an approximate 10-point difference between the mean scores of Management Commitment to Safety for career and volunteer departments in both samples. We observed associations for two organizational outcomes, Safety Behavior and Job Satisfaction, with Management Commitment to Safety and Supervisor Support for Safety overall and when stratified by organization type. We observed a decrease in the odds of injuries associated with a one-unit increase in Management Commitment to Safety (OR 1.0 overall : 0.98, 95% CI 0.97-0.99; OR 2.0 volunteer : 0.90, 95% CI 0.85-0.95) and Supervisor Support for Safety (OR 1.0 overall : 0.95, 95% CI 0.93-0.97; OR 1.0 career : 0.95, 95% CI 0.92-0.98)., Conclusions: From our current study, and a prior analysis of a geographically stratified random sample of U.S. fire departments, we identified that from all the organizational outcomes, job satisfaction was most consistently associated with FOCUS safety climate. Further, firefighters in our samples consistently rated Supervisor Support for Safety higher than Management Commitment to Safety. Future interventions should support fire departments in improving their departmental Management Commitment to Safety and maintaining their Supervisor for Safety., (© 2024. The Author(s).)

The chemical and isotopic composition of stony coral skeletons form an important archive of past climate. However, these reconstructions are largely based on empirical relationships often complicated by "vital effects" arising from uncertain physiological processes of the coral holobiont. The skeletons of deep-sea corals, such as Desmophyllum dianthus, are characterised by micron-scale or larger geochemical heterogeneity associated with: (1) centres of calcification (COCs) where nucleation of new skeleton begins, and (2) fibres that thicken the skeleton. These features are difficult to sample cleanly using traditional techniques, resulting in uncertainty surrounding both the causes of geochemical differences and their influence on environmental signals. Here we combine optical, and in-situ chemical and isotopic, imaging tools across a range of spatial resolutions (~ 100 nm to 10 s of μm) in a correlative multimodal imaging (CMI) approach to isolate the microstructural geochemistry of each component. This reveals COCs are characterised by higher organic content, Mg, Li and Sr and lower U, B and δ 11 B compared to fibres, reflecting the contrasting biomineralisation mechanisms employed to construct each feature. CMI is rarely applied in Environmental/Earth Sciences, but here we illustrate the power of this approach to unpick the "vital effects" in D. dianthus, and by extension, other scleractinian corals., (© 2024. The Author(s).)

Background: Ambient air pollution contributes to an estimated 6.67 million deaths annually, and has been linked to cardiovascular disease (CVD), the leading cause of death. Short-term increases in air pollution have been associated with increased risk of CVD event, though relatively few studies have directly compared effects of multiple pollutants using fine-scale spatio-temporal data, thoroughly adjusting for co-pollutants and temperature, in an exhaustive citywide hospitals dataset, towards identifying key pollution sources within the urban environment to most reduce, and reduce disparities in, the leading cause of death worldwide., Objectives: We aimed to examine multiple pollutants against multiple CVD diagnoses, across lag days, in models adjusted for co-pollutants and meteorology, and inherently adjusted by design for non-time-varying individual and aggregate-level covariates, using fine-scale space-time exposure estimates, in an exhaustive dataset of emergency department visits and hospitalizations across an entire city, thereby capturing the full population-at-risk., Methods: We used conditional logistic regression in a case-crossover design - inherently controlling for all confounders not varying within case month - to examine associations between spatio-temporal nitrogen dioxide (NO 2 ), fine particulate matter (PM 2.5 ), sulfur dioxide (SO 2 ), and ozone (O 3 ) in New York City, 2005-2011, on individual risk of acute CVD event (n = 837,523), by sub-diagnosis [ischemic heart disease (IHD), heart failure (HF), stroke, ischemic stroke, acute myocardial infarction]., Results: We found significant same-day associations between NO 2 and risk of overall CVD, IHD, and HF - and between PM 2.5 and overall CVD or HF event risk - robust to all adjustments and multiple comparisons. Results were comparable by sex and race - though median age at CVD was 10 years younger for Black New Yorkers than White New Yorkers. Associations for NO 2 were comparable for adults younger or older than 69 years, though PM 2.5 associations were stronger among older adults., Discussion: Our results indicate immediate, robust effects of combustion-related pollution on CVD risk, by sub-diagnosis. Though acute impacts differed minimally by age, sex, or race, the much younger age-at-event for Black New Yorkers calls attention to cumulative social susceptibility., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Subsurface water masses formed at high latitudes impact the latitudinal distribution of heat in the ocean. Yet uncertainty surrounding the timing of low-latitude warming during the last deglaciation (18-10 ka) means that controls on sub-surface temperature rise remain unclear. Here we present seawater temperature records on a precise common age-scale from East Equatorial Pacific (EEP), Equatorial Atlantic, and Southern Ocean intermediate waters using new Li/Mg records from cold water corals. We find coeval warming in the tropical EEP and Atlantic during Heinrich Stadial 1 (+ 6 °C) that closely resemble warming recorded in Antarctic ice cores, with more modest warming of the Southern Ocean (+ 3 °C). The magnitude and depth of low-latitude ocean warming implies that downward accumulation of heat following Atlantic Meridional Overturning Circulation (AMOC) slowdown played a key role in heating the ocean interior, with heat advection from southern-sourced intermediate waters playing an additional role., (© 2023. The Author(s).)

Subglacial discharge from the Antarctic Ice Sheet (AIS) likely played a crucial role in the loss of the ice sheet and the subsequent rise in sea level during the last deglaciation. However, no direct proxy is currently available to document subglacial discharge from the AIS, which leaves significant gaps in our understanding of the complex interactions between subglacial discharge and ice-sheet stability. Here we present deep-sea coral 234 U/ 238 U records from the Drake Passage in the Southern Ocean to track subglacial discharge from the AIS. Our findings reveal distinctively higher seawater 234 U/ 238 U values from 15,400 to 14,000 years ago, corresponding to the period of the highest iceberg-rafted debris flux and the occurrence of the meltwater pulse 1A event. This correlation suggests a causal link between enhanced subglacial discharge, synchronous retreat of the AIS, and the rapid rise in sea levels. The enhanced subglacial discharge and subsequent AIS retreat appear to have been preconditioned by a stronger and warmer Circumpolar Deep Water, thus underscoring the critical role of oceanic heat in driving major ice-sheet retreat., (© 2023. The Author(s).)

Fine particulate matter (PM 2.5 ) and aeroallergens (i.e., pollen, molds) are known triggers of asthma exacerbation. Despite mechanistic evidence suggesting synergistic effects between PM 2.5 and asthma exacerbation, little epidemiologic work has been performed in children, which has exhibited inconsistency. We conducted a time-series study to explore their interactions using electronic health records (EHR) data in Philadelphia, PA, for asthma diagnoses in outpatient, emergency department [ED], and inpatient settings. Daily asthma exacerbation cases (28,540 asthma exacerbation case encounters) were linked to daily ambient PM 2.5 and daily aeroallergen levels during the aeroallergen season of a six-year period (mid-March to October 2011-2016). Asthma exacerbation counts were modeled using quasi-Poisson regression, where PM 2.5 and aeroallergens were fitted with distributed lag non-linear functions (lagged from 0 to 14-days), respectively, when modeled as the primary exposure variables. Regression models were adjusted for mean daily temperature/relative humidity, long-term and seasonal trends, day-of-week, and major U.S. holidays. Increasing gradient of RR estimates were observed for only a few primary exposure risk factors [PM 2.5 (90th vs. 5th percentile)/aeroallergens (90th percentile vs. 0)], across different levels of effect modifiers. For example, RRs for the association between late-season grass pollen (lag1) and asthma exacerbation were higher at higher levels of PM 2.5 , 5-days preceding the exacerbation event (low PM 2.5 : RR = 1.01, 95% CI: 0.93-1.09; medium PM 2.5 : 1.04, 95% CI: 0.96-1.12; high PM 2.5 : 1.09, 95% CI: 1.01-1.19). However, most of the highest RRs for aeroallergens were instead observed for days with low- or medium- PM 2.5 levels; likewise, when PM 2.5 was modeled as the primary exposure with aeroallergens as the effect modifier. Most of the RR estimates did not exhibit gradients that suggested synergism, and were of relatively high imprecision. Overall, our study suggested no evidence for interactions between PM 2.5 and aeroallergens in their relationships with childhood asthma exacerbation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Although people with chronic kidney disease (CKD) and obesity have important motivations to lose weight, weight loss is also associated with health risks. We examined whether patterns of change in systolic blood pressure (SBP), serum albumin level, and fat-free mass (FFM) can help to differentiate between healthy and high-risk weight loss in this population., Methods: Using data from the Chronic Renal Insufficiency Cohort Study (CRIC), we estimated a joint multivariate latent class model with 6 classes to identify distinct trajectories of body mass index (BMI), albumin, and SBP among participants with obesity (BMI ≥30 kg/m 2 at baseline), accounting for informative missingness from death. In a secondary analysis, we fit a 6-class model with BMI and FFM., Results: Among 2831 participants (median baseline BMI 35.6, interquartile range [IQR] 32.4-40.0 kg/m 2 ), median follow-up was 6.8 (IQR 4.8-12.9) years, median age was 61 (IQR 54-67) years, 53% were male, 50% were non-Hispanic Black, and 82% were trying to control or lose weight at baseline. Latent classes were associated with mortality risk (5-year cumulative incidence of mortality 6.8% and 1.5% in class 6 and 3, respectively). Class 6 had the highest mortality rate and was characterized by early, steep BMI loss, early serum albumin decline, and late SBP increase. In the secondary analysis, a class characterized by steep BMI and FFM loss was associated with the highest death risk., Conclusions: Among adults with CKD and obesity, BMI loss with concomitant serum albumin or FFM loss was associated with a high risk of death., (© 2023 International Society of Nephrology. Published by Elsevier Inc.)

Anthropogenic carbon emissions are causing seawater pH to decline, yet the impact on marine calcifiers is uncertain. Scleractinian corals and coralline algae strongly elevate the pH of their calcifying fluid (CF) to promote calcification. Other organisms adopt less energetically demanding calcification approaches but restrict their habitat. Stylasterid corals occur widely (extending well below the carbonate saturation horizon) and precipitate both aragonite and high-Mg calcite, however, their mode of biocalcification and resilience to ocean acidification are unknown. Here we measure skeletal boron isotopes (δ 11 B), B/Ca, and U/Ca to provide the first assessment of pH and rate of seawater flushing of stylasterid CF. Remarkably, both aragonitic and high-Mg calcitic stylasterids have low δ 11 B values implying little modification of internal pH. Collectively, our results suggest stylasterids have low seawater exchange rates into the calcifying space or rely on organic molecule templating to facilitate calcification. Thus, despite occupying similar niches to Scleractinia, Stylasteridae exhibit highly contrasting biocalcification, calling into question their resilience to ocean acidification., (© 2022. The Author(s).)

Studies have suggested that adults with gallbladder disease have increased risk of type 2 diabetes. This prospective cohort study assessed the risk of type 2 diabetes in postmenopausal women with gallbladder disease. Data from women enrolled in the Women's Health Initiative from 1993 to 2005, aged 50-79 years (mean = 63.2; standard deviation, 7.2), were analyzed. Cox proportional hazards regression models were used to estimate the risk of type 2 diabetes associated with gallbladder disease. There were 8,896 new cases of type 2 diabetes after 1,025,486 person-years of follow-up. Gallbladder disease was significantly associated with type 2 diabetes (hazard ratio = 1.52; 95% confidence interval (CI): 1.38,1.67). The observed risk of type 2 diabetes in women with both gallbladder disease and central obesity was 37% higher than expected (relative excess risk due to interaction = 0.37, 95% CI: 0.11,0.63) on the additive scale. The hazard ratios for type 2 diabetes associated with gallbladder disease were 1.25 (95% CI: 1.19,1.32) and 1.48 (95% CI: 1.34,1.63) in women with and without central obesity, respectively, on the multiplicative scale. Results of this study support further studies to determine whether interventions in older women with gallbladder disease would reduce type 2 diabetes risk, especially among those with central obesity. Future research should examine the pathophysiological basis of the association between gallbladder disease and type 2 diabetes., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives. To evaluate the occurrence of HIV and COVID-19 infections in Philadelphia, Pennsylvania, through July 2020 and identify ecological correlates driving racial disparities in infection incidence. Methods. For each zip code tabulation area, we created citywide comparison Z -score measures of COVID-19 cases, new cases of HIV, and the difference between the scores. Choropleth maps were used to identify areas that were similar or dissimilar in terms of disease patterning, and weighted linear regression models helped identify independent ecological predictors of these patterns. Results. Relative to COVID-19, HIV represented a greater burden in Center City Philadelphia, whereas COVID-19 was more apparent in Northeast Philadelphia. Areas with a greater proportion of Black or African American residents were overrepresented in terms of both diseases. Conclusions. Although race is a shared nominal upstream factor that conveys increased risk for both infections, an understanding of separate structural, demographic, and economic risk factors that drive the overrepresentation of COVID-19 cases in racial/ethnic communities across Philadelphia is critical. Public Health Implications. Difference-based measures are useful in identifying areas that are underrepresented or overrepresented with respect to disease occurrence and may be able to elucidate effective or ineffective mitigation strategies. ( Am J Public Health . 2022;112(3):408-416. https://doi.org/10.2105/AJPH.2021.306538).

One of the most conserved traits in the evolution of biomineralizing organisms is the taxon-specific selection of skeletal minerals. All modern scleractinian corals are thought to produce skeletons exclusively of the calcium-carbonate polymorph aragonite. Despite strong fluctuations in ocean chemistry (notably the Mg/Ca ratio), this feature is believed to be conserved throughout the coral fossil record, spanning more than 240 million years. Only one example, the Cretaceous scleractinian coral Coelosmilia (ca. 70 to 65 Ma), is thought to have produced a calcitic skeleton. Here, we report that the modern asymbiotic scleractinian coral Paraconotrochus antarcticus living in the Southern Ocean forms a two-component carbonate skeleton, with an inner structure made of high-Mg calcite and an outer structure composed of aragonite. P. antarcticus and Cretaceous Coelosmilia skeletons share a unique microstructure indicating a close phylogenetic relationship, consistent with the early divergence of P. antarcticus within the Vacatina (i.e., Robusta) clade, estimated to have occurred in the Mesozoic (ca. 116 Mya). Scleractinian corals thus join the group of marine organisms capable of forming bimineralic structures, which requires a highly controlled biomineralization mechanism; this capability dates back at least 100 My. Due to its relatively prolonged isolation, the Southern Ocean stands out as a repository for extant marine organisms with ancient traits., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)

The Southern Ocean plays a crucial role in regulating atmospheric CO 2 on centennial to millennial time scales. However, observations of sufficient resolution to explore this have been lacking. Here, we report high-resolution, multiproxy records based on precisely dated deep-sea corals from the Southern Ocean. Paired deep (∆ 14 C and δ 11 B) and surface (δ 15 N) proxy data point to enhanced upwelling coupled with reduced efficiency of the biological pump at 14.6 and 11.7 thousand years (ka) ago, which would have facilitated rapid carbon release to the atmosphere. Transient periods of unusually well-ventilated waters in the deep Southern Ocean occurred at 16.3 and 12.8 ka ago. Contemporaneous atmospheric carbon records indicate that these Southern Ocean ventilation events are also important in releasing respired carbon from the deep ocean to the atmosphere. Our results thus highlight two distinct modes of Southern Ocean circulation and biogeochemistry associated with centennial-scale atmospheric CO 2 jumps during the last deglaciation., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Runoff from heavy precipitation events can lead to microbiological contamination of source waters for public drinking water supplies. Philadelphia is a city of interest for a study of waterborne acute gastrointestinal illness (AGI) because of frequent heavy precipitation, extensive impervious landcover, and combined sewer systems that lead to overflows. We conducted a time-series analysis of the association between heavy precipitation and AGI incidence in Philadelphia, served by drinking water from Delaware River and Schuylkill River source waters. AGI cases on each day during the study period (2015-2017) were captured through syndromic surveillance of patients' chief complaint upon presentation at local emergency departments. Daily precipitation was represented by measurements at the Philadelphia International Airport and by modeled precipitation within the watershed boundaries, and we also evaluated stream flowrate as a proxy of precipitation. We estimated the association using distributed lag nonlinear models, assuming a quasi-Poisson distribution of the outcome variable and with adjustment for potential confounding by seasonal and long-term time trends, ambient temperature, day-of-week, and major holidays. We observed an association between heavy precipitation and AGI incidence in Philadelphia that was primarily limited to the spring season, with significant increases in AGI that peaked from 8 to 16 days following a heavy precipitation event. For example, the increase in AGI incidence related to airport precipitation above the 95th percentile (vs no precipitation) during spring reached statistical significance on lag day 7, peaked on day 16 (102% increase, 95% confidence interval: 16%, 252%), and declined while remaining significantly elevated through day 28. Similar associations were observed in analyses of watershed-specific precipitation in relation to AGI cases within the populations served by drinking water from each river. Our results suggest that heavy precipitation events in Philadelphia result in detectable local increases in waterborne AGI., Competing Interests: The authors have declared that they have no competing interests.

Epidemiologic evidence consistently links urban air pollution exposures to health, even after adjustment for potential spatial confounding by socioeconomic position (SEP), given concerns that air pollution sources may be clustered in and around lower-SEP communities. SEP, however, is often measured with less spatial and temporal resolution than are air pollution exposures (i.e., census-tract socio-demographics vs. fine-scale spatio-temporal air pollution models). Although many questions remain regarding the most appropriate, meaningful scales for the measurement and evaluation of each type of exposure, we aimed to compare associations for multiple air pollutants and social factors against cardiovascular disease (CVD) event rates, with each exposure measured at equal spatial and temporal resolution. We found that, in multivariable census-tract-level models including both types of exposures, most pollutant-CVD associations were non-significant, while most social factors retained significance. Similarly, the magnitude of association was higher for an IQR-range difference in the social factors than in pollutant concentrations. We found that when offered equal spatial and temporal resolution, CVD was more strongly associated with social factors than with air pollutant exposures in census-tract-level analyses in New York City., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

The deep sea is the largest biome on earth, and microbes dominate in biomass and abundance. Anthropogenic litter is now almost ubiquitous in this biome, and its deposition creates new habitats and environments, including for microbial assemblages. With the ever increasing accumulation of this debris, it is timely to identify and describe the bacterial and archaeal communities that are able to form biofilms on macrodebris in the deep sea. Using 16S rRNA gene high throughput sequencing, we show for the first time the composition of bacteria and archaea on macrodebris collected from the deep sea. Our data suggest differences in the microbial assemblage composition across litter of different materials including metal, rubber, glass, fabric and plastic. These results imply that anthropogenic macrodebris provide diverse habitats for bacterial and archaeal biofilms and each may harbour distinct microbial communities., Competing Interests: The authors have declared that no competing interests exist.

The cause of changes in atmospheric carbon dioxide (CO 2 ) during the recent ice ages is yet to be fully explained. Most mechanisms for glacial-interglacial CO 2 change have centred on carbon exchange with the deep ocean, owing to its large size and relatively rapid exchange with the atmosphere 1 . The Southern Ocean is thought to have a key role in this exchange, as much of the deep ocean is ventilated to the atmosphere in this region 2 . However, it is difficult to reconstruct changes in deep Southern Ocean carbon storage, so few direct tests of this hypothesis have been carried out. Here we present deep-sea coral boron isotope data that track the pH-and thus the CO 2 chemistry-of the deep Southern Ocean over the past forty thousand years. At sites closest to the Antarctic continental margin, and most influenced by the deep southern waters that form the ocean's lower overturning cell, we find a close relationship between ocean pH and atmospheric CO 2 : during intervals of low CO 2 , ocean pH is low, reflecting enhanced ocean carbon storage; and during intervals of rising CO 2 , ocean pH rises, reflecting loss of carbon from the ocean to the atmosphere. Correspondingly, at shallower sites we find rapid (millennial- to centennial-scale) decreases in pH during abrupt increases in CO 2 , reflecting the rapid transfer of carbon from the deep ocean to the upper ocean and atmosphere. Our findings confirm the importance of the deep Southern Ocean in ice-age CO 2 change, and show that deep-ocean CO 2 release can occur as a dynamic feedback to rapid climate change on centennial timescales.

Abrupt climate changes in the past have been attributed to variations in Atlantic Meridional Overturning Circulation (AMOC) strength. However, the exact timing and magnitude of past AMOC shifts remain elusive, which continues to limit our understanding of the driving mechanisms of such climate variability. Here we show a consistent signal of the 231 Pa/ 230 Th proxy that reveals a spatially coherent picture of western Atlantic circulation changes over the last deglaciation, during abrupt millennial-scale climate transitions. At the onset of deglaciation, we observe an early slowdown of circulation in the western Atlantic from around 19 to 16.5 thousand years ago (ka), consistent with the timing of accelerated Eurasian ice melting. The subsequent weakened AMOC state persists for over a millennium (~16.5-15 ka), during which time there is substantial ice rafting from the Laurentide ice sheet. This timing indicates a role for melting ice in driving a two-step AMOC slowdown, with a positive feedback sustaining continued iceberg calving and climate change during Heinrich Stadial 1.

Seamounts are proposed to be hotspots of deep-sea biodiversity, a pattern potentially arising from increased productivity in a heterogeneous landscape leading to either high species co-existence or species turnover (beta diversity). However, studies on individual seamounts remain rare, hindering our understanding of the underlying causes of local changes in beta diversity. Here, we investigated processes behind beta diversity using ROV video, coupled with oceanographic and quantitative terrain parameters, over a depth gradient in Annan Seamount, Equatorial Atlantic. By applying recently developed beta diversity analyses, we identified ecologically unique sites and distinguished between two beta diversity processes: species replacement and changes in species richness. The total beta diversity was high with an index of 0.92 out of 1 and was dominated by species replacement (68%). Species replacement was affected by depth-related variables, including temperature and water mass in addition to the aspect and local elevation of the seabed. In contrast, changes in species richness component were affected only by the water mass. Water mass, along with substrate also affected differences in species abundance. This study identified, for the first time on seamount megabenthos, the different beta diversity components and drivers, which can contribute towards understanding and protecting regional deep-sea biodiversity.

It is known that the price of food influences the purchasing and consumption decisions of individuals; however, little work has examined if the price of healthier food relative to unhealthier food in an individual's neighborhood is associated with overall dietary quality while using data from multiple regions in the United States. Cross-sectional person-level data came from The Multi-Ethnic Study of Atherosclerosis (exam 5, 2010-2012 n = 2765); a food frequency questionnaire assessed diet. Supermarket food/beverage prices came from Information Resources Inc. (n = 794 supermarkets). For each individual, the average price of select indicators of healthier foods (vegetables, fruits, dairy) and unhealthier foods (soda, sweets, salty snacks), as well as their ratio, was computed for supermarkets within three miles of the person's residential address. Logistic regression estimated odds ratios of a high-quality diet (top quintile of Healthy Eating Index 2010) associated with healthy-to-unhealthy price ratio, adjusted for individual and neighborhood characteristics. Sensitivity analyses used an instrumental variable (IV) approach. Healthier foods cost nearly twice as much as unhealthier foods per serving on average (mean healthy-to-unhealthy ratio = 1.97 [SD 0.14]). A larger healthy-to-unhealthy price ratio was associated with lower odds of a high-quality diet (OR = 0.76 per SD increase in the ratio, 95% CI = [0.64-0.9]). IV analyses largely confirmed these findings although-as expected with IV adjustment-confidence intervals were wide (OR = 0.82 [0.57-1.19]). Policies to address the large price differences between healthier and unhealthy foods may help improve diet quality in the United States., Competing Interests: The authors declare no conflicts of interest.

Background: Turbidity has been used as an indicator of microbiological contamination of drinking water in time-series studies attempting to discern the presence of waterborne gastrointestinal illness; however, the utility of turbidity as a proxy exposure measure has been questioned., Objectives: We conducted a review of epidemiological studies of the association between turbidity of drinking-water supplies and incidence of acute gastrointestinal illness (AGI), including a synthesis of the overall weight of evidence. Our goal was to evaluate the potential for causal inference from the studies., Methods: We identified 14 studies on the topic (distinct by region, time period and/or population). We evaluated each study with regard to modeling approaches, potential biases, and the strength of evidence. We also considered consistencies and differences in the collective results., Discussion: Positive associations between drinking-water turbidity and AGI incidence were found in different cities and time periods, and with both unfiltered and filtered supplies. There was some evidence for a stronger association at higher turbidity levels. The studies appeared to adequately adjust for confounding. There was fair consistency in the notable lags between turbidity measurement and AGI identification, which fell between 6 and 10 d in many studies., Conclusions: The observed associations suggest a detectable incidence of waterborne AGI from drinking water in the systems and time periods studied. However, some discrepant results indicate that the association may be context specific. Combining turbidity with seasonal and climatic factors, additional water quality measures, and treatment data may enhance predictive modeling in future studies. https://doi.org/10.1289/EHP1090.

This paper evaluates variation in food prices within and between neighborhoods to improve our understanding of access to healthy foods in urbanized areas and potential economic incentives and barriers to consuming a higher-quality diet. Prices of a selection of healthier foods (dairy, fruit juice, and frozen vegetables) and unhealthy foods (soda, sweets, and salty snacks) were obtained from 1953 supermarkets across the USA during 2009-2012 and were linked to census block group socio-demographics. Analyses evaluated associations between neighborhood SES and proportion Black/Hispanic and the prices of healthier and unhealthy foods, and the relative price of healthier foods compared with unhealthy foods (healthy-to-unhealthy price ratio). Linear hierarchical regression models were used to explore geospatial variation and adjust for confounders. Overall, the price of healthier foods was nearly twice as high as the price of unhealthy foods ($0.590 vs $0.298 per serving; healthy-to-unhealthy price ratio of 1.99). This trend was consistent across all neighborhood characteristics. After adjusting for covariates, no association was found between food prices (healthy, unhealthy, or the healthy-to-unhealthy ratio) and neighborhood SES. Similarly, there was no association between the proportion Black/Hispanic and healthier food price, a very small positive association with unhealthy price, and a modest negative association with the healthy-to-unhealthy ratio. No major differences were seen in food prices across levels of neighborhood SES and proportion Black/Hispanic; however, the price of healthier food was twice as expensive as unhealthy food per serving on average.

The Southern Ocean regulates the ocean's biological sequestration of CO 2 and is widely suspected to underpin much of the ice age decline in atmospheric CO 2 concentration, but the specific changes in the region are debated. Although more complete drawdown of surface nutrients by phytoplankton during the ice ages is supported by some sediment core-based measurements, the use of different proxies in different regions has precluded a unified view of Southern Ocean biogeochemical change. Here, we report measurements of the 15 N/ 14 N of fossil-bound organic matter in the stony deep-sea coral Desmophyllum dianthus , a tool for reconstructing surface ocean nutrient conditions. The central robust observation is of higher 15 N/ 14 N across the Southern Ocean during the Last Glacial Maximum (LGM), 18-25 thousand years ago. These data suggest a reduced summer surface nitrate concentration in both the Antarctic and Subantarctic Zones during the LGM, with little surface nitrate transport between them. After the ice age, the increase in Antarctic surface nitrate occurred through the deglaciation and continued in the Holocene. The rise in Subantarctic surface nitrate appears to have had both early deglacial and late deglacial/Holocene components, preliminarily attributed to the end of Subantarctic iron fertilization and increasing nitrate input from the surface Antarctic Zone, respectively.

In the USA, little is known about local variation in retail cigarette prices; price variation explained by taxes, bans, and area-level socio-demographics, and whether taxes and hospitality bans have synergistic effects on smoking prevalence. Cigarette prices 2001-2011 from chain supermarkets and drug stores ( n = 2973) were linked to state taxes ( n = 41), state and county bar/restaurant smoking bans, and census block group socio-demographics. Hierarchical models explored effects of taxes and bans on retail cigarette prices as well as county smoking prevalence (daily, non-daily). There was wide variation in store-level cigarette prices in part due to differences in state excise taxes. Excise taxes were only partially passed onto consumers (after adjustment, $1 tax associated with $0.90 increase in price, p < 0.0001) and the pass-through was slightly higher in areas that had bans but did not differ by area-level socio-demographics. Bans were associated with a slight increase in cigarette price (after adjustment, $0.09 per-pack, p < 0.0001). Taxes and bans were associated with reduction in smoking prevalence and taxes had a stronger association when combined with bans, suggesting a synergistic effect. Given wide variation in store-level prices, and uneven state/county implementation of taxes and bans, more federal policies should be considered.

Objective: Focal epilepsies, such as temporal lobe epilepsy (TLE), are known to disrupt network activity in areas outside the epileptogenic zone [Tracy et al., 2015]. We devised a measure of temporal instability of resting state functional connectivity (FC), capturing temporal variations of BOLD correlations between brain regions that is less confounded than the "sliding window" approach common in the literature., Methods: We investigated healthy controls and unilateral TLE patients (right and left seizure focus groups), utilizing group ICA to identify the default mode network (DMN), a network associated with episodic memory, a key cognitive deficit in TLE. Our instability analyses focused on: (1) connectivity between DMN region pairs, both within and between TLE patients and matched controls, (2) whole brain group differences between region pairs ipsilateral or contralateral to the epileptogenic temporal lobe., Results: For both the whole brain and a more focused analysis of DMN region pairs, temporal stability appears to characterize the healthy brain. The TLE patients displayed more FC instability compared to controls, with this instability more pronounced for the right TLE patients., Significance: Our findings challenge the view that the resting state signal is stable over time, providing a measure of signal coherence change that may generate insights into the temporal components of network organization. The precuneus was the region within the DMN consistently expressing this instability, suggesting this region plays a key role in large scale temporal dynamics of the DMN, with such dynamics disrupted in TLE, putting key cognitive functions at risk. Hum Brain Mapp 38:528-540, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Objective: Soda consumption is high in the USA, especially among minorities and individuals of lower socio-economic status (SES); this may be due to its affordable price in relation to healthier alternatives. The objective of the present study was to examine geospatial variation in price of milk and soda, and the price of milk relative to soda, by neighbourhood SES and proportion of Hispanic and black individuals., Design: Retailer soda and milk prices (n 2987; Information Resources, Inc. Academic Data Set 2004-2011) were linked to census block group sociodemographic characteristics (American Community Survey 2005-2009). Linear hierarchical regression models were used to adjust for confounders., Setting: Large chain supermarkets and superstores (n 1743) in forty-one states and 1694 block groups (USA)., Results: For equivalent fluid ounces, price of soda on average was 62 % lower than milk ($US 0·23 v. $US 0·63 per serving) and there was high dispersion in milk price across geographic areas. After adjustment for confounding, neighbourhoods with a higher concentration of black and Hispanic individuals tended to have lower soda prices and higher milk prices (-$US 0·001 and +$US 0·007 in price per serving, respectively, for a one quintile increase in black/Hispanic population), while soda and milk both became less expensive as SES decreased (-$US 0·002 and -$US 0·015 in serving price per one sd decrease in SES index, respectively)., Conclusions: Neighbourhoods with a higher concentration of blacks and Hispanics may be at greater risk of higher soda consumption due to more affordable prices, in absolute terms and relative to the price of milk.

Plastic waste is a distinctive indicator of the world-wide impact of anthropogenic activities. Both macro- and micro-plastics are found in the ocean, but as yet little is known about their ultimate fate and their impact on marine ecosystems. In this study we present the first evidence that microplastics are already becoming integrated into deep-water organisms. By examining organisms that live on the deep-sea floor we show that plastic microfibres are ingested and internalised by members of at least three major phyla with different feeding mechanisms. These results demonstrate that, despite its remote location, the deep sea and its fragile habitats are already being exposed to human waste to the extent that diverse organisms are ingesting microplastics.

The strength of Atlantic meridional overturning circulation is believed to affect the climate over glacial-interglacial and millennial timescales. The marine sedimentary (231)Pa/(230)Th ratio is a promising paleocirculation proxy, but local particle effects may bias individual reconstructions. Here we present new Atlantic sedimentary (231)Pa/(230)Th data from the Holocene, the last glacial maximum and Heinrich Stadial 1, a period of abrupt cooling ca. 17,500 years ago. We combine our results with published data from these intervals to create a spatially distributed sedimentary (231)Pa/(230)Th database. The data reveal a net (231)Pa deficit during each period, consistent with persistent (231)Pa export. In highly resolved cores, Heinrich (231)Pa/(230)Th ratios exceed glacial ratios at nearly all depths, indicating a significant reduction, although not cessation, of overturning during Heinrich Stadial 1. These results support the inference that weakened overturning was a driver of Heinrich cooling, while suggesting that abrupt climate oscillations do not necessarily require a complete shutdown of overturning.

Today's Sargasso Sea is nutrient starved, except for episodic upwelling events caused by wind-driven winter mixing and eddies. Enhanced diatom opal burial in Sargasso Sea sediments indicates that silicic acid, a limiting nutrient today, may have been more available in subsurface waters during Heinrich Stadials, millennial-scale climate perturbations of the last glacial and deglaciation. Here we use the geochemistry of opal-forming organisms from different water depths to demonstrate changes in silicic acid supply and utilization during the most recent Heinrich Stadial. We suggest that during the early phase (17.5-18 ka), wind-driven upwelling replenished silicic acid to the subsurface, resulting in low Si utilization. By 17 ka, stratification reduced the surface silicic acid supply leading to increased Si utilization efficiency. This abrupt shift in Si cycling would have contributed to high regional carbon export efficiency during the recent Heinrich Stadial, despite being a period of increasing atmospheric CO2.

The ocean interacts with the atmosphere, biosphere and cryosphere in a complex way, modulating climate through the storage and transport of heat, nutrients and carbon. As such, it is important that we understand the ways in which the ocean behaves and the factors that can lead to change. In order to gain this understanding, we need to look back into the past, on time scales from recent decadal-scale change, through the abrupt changes of the Pleistocene and back to times when the Earth's climate was significantly different than the Holocene. A key challenge facing the field of palaeoceanography is to combine data and modelling in a common framework. Coupling palaeo-data and models should improve our knowledge of how the Earth works, and perhaps of more direct societal relevance, might enable us to provide better predictive capabilities in climate modelling. In this discussion paper, we examine the motivations, past successes and challenges facing palaeoceanographic studies. We then suggest a number of areas and approaches that we believe will allow palaeoceanography to continue to provide new insights into processes that affect future climate change.

Seamounts are unique deep-sea features that create habitats thought to have high levels of endemic fauna, productive fisheries and benthic communities vulnerable to anthropogenic impacts. Many seamounts are isolated features, occurring in the high seas, where access is limited and thus biological data scarce. There are numerous seamounts within the Drake Passage (Southern Ocean), yet high winds, frequent storms and strong currents make seafloor sampling particularly difficult. As a result, few attempts to collect biological data have been made, leading to a paucity of information on benthic habitats or fauna in this area, particularly those on primarily hard-bottom seamounts and ridges. During a research cruise in 2008 six locations were examined (two on the Antarctic margin, one on the Shackleton Fracture Zone, and three on seamounts within the Drake Passage), using a towed camera with onboard instruments to measure conductivity, temperature, depth and turbidity. Dominant fauna and bottom type were categorized from 200 randomized photos from each location. Cold-water corals were present in high numbers in habitats both on the Antarctic margin and on the current swept seamounts of the Drake Passage, though the diversity of orders varied. Though the Scleractinia (hard corals) were abundant on the sedimented margin, they were poorly represented in the primarily hard-bottom areas of the central Drake Passage. The two seamount sites and the Shackleton Fracture Zone showed high numbers of stylasterid (lace) and alcyonacean (soft) corals, as well as large numbers of sponges. Though data are preliminary, the geological and environmental variability (particularly in temperature) between sample sites may be influencing cold-water coral biogeography in this region. Each area observed also showed little similarity in faunal diversity with other sites examined for this study within all phyla counted. This manuscript highlights how little is understood of these isolated features, particularly in Polar regions.

We present a detailed history of glacial to Holocene radiocarbon in the deep western North Atlantic from deep-sea corals and paired benthic-planktonic foraminifera. The deglaciation is marked by switches between radiocarbon-enriched and -depleted waters, leading to large radiocarbon gradients in the water column. These changes played an important role in modulating atmospheric radiocarbon. The deep-ocean record supports the notion of a bipolar seesaw with increased Northern-source deep-water formation linked to Northern Hemisphere warming and the reverse. In contrast, the more frequent radiocarbon variations in the intermediate/deep ocean are associated with roughly synchronous changes at the poles.

The large variation in the ratio of uranium-234 to uranium-238 (234U/238U) in rivers is not well understood, but may provide information about past weathering and rainfall and is important because it controls seawater (234U/238U). Here, we demonstrate the importance of physical weathering and rainfall for (234U/238U), using rivers from South Island, New Zealand. These data allow interpretation of an existing speleothem (234U/238U) record and suggest that New Zealand glacier advance 13,000 years ago was influenced by increased rainfall rather than by Younger Dryas-like cooling. A model of seawater (234U/238U) during glacial cycles indicates that rejection of corals based on modern (234U/238U) +/- <0.01 is not merited and may reject the highest quality ages.