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Creators/Authors contains: "Friedman, Sarah"

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  1. North Atlantic Deep Water (NADW), the return flow component of the Atlantic Meridional Overturning Circulation (AMOC), is a major inter-hemispheric ocean water mass with strong climate effects but the evolution of its source components on million-year timescales is poorly known. Today, two major NADW components that flow southward over volcanic ridges to the east and west of Iceland are associated with distinct contourite drift systems that are forming off the coast of Greenland and on the eastern flank of the Reykjanes (mid-Atlantic) Ridge. Here we provide direct records of the early history of this drift sedimentation based on cores collected during International Ocean Discovery Programme (IODP) Expeditions 395C and 395. We find rapid acceleration of drift deposition linked to the eastern component of NADW, known as Iceland–Scotland Overflow Water at 3.6 million years ago (Ma). In contrast, the Denmark Strait Overflow Water feeding the western Eirik Drift has been persistent since the Late Miocene. These observations constrain the long-term evolution of the two NADW components, revealing their contrasting independent histories and allowing their links with climatic events such as Northern Hemisphere cooling at 3.6 Ma, to be assessed. 
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    Free, publicly-accessible full text available May 5, 2026
  2. The deep sea contains a surprising diversity of life, including iconic fish groups such as anglerfishes and lanternfishes. Still, >65% of marine teleost fish species are restricted to the photic zone <200 m, which comprises less than 10% of the ocean’s total volume. From a macroevolutionary perspective, this paradox may be explained by three hypotheses: 1) shallow water lineages have had more time to diversify than deep-sea lineages, 2) shallow water lineages have faster rates of speciation than deep-sea lineages, or 3) shallow-to-deep sea transition rates limit deep-sea richness. Here we use phylogenetic comparative methods to test among these three non-mutually exclusive hypotheses. While we found support for all hypotheses, the disparity in species richness is better described as the uneven outcome of alternating phases that favored shallow or deep diversification over the past 200 million y. Shallow marine teleosts became incredibly diverse 100 million y ago during a period of warm temperatures and high sea level, suggesting the importance of reefs and epicontinental settings. Conversely, deep-sea colonization and speciation was favored during brief episodes when cooling temperatures increased the efficiency of the ocean’s carbon pump. Finally, time-variable ecological filters limited shallow-to-deep colonization for much of teleost history, which helped maintain higher shallow richness. A pelagic lifestyle and large jaws were associated with early deep-sea colonists, while a demersal lifestyle and a tapered body plan were typical of later colonists. Therefore, we also suggest that some hallmark characteristics of deep-sea fishes evolved prior to colonizing the deep sea. 
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  3. Direct-to-consumer advertisements for healthcare services constitute a rare channel of public communication where consumers see and hear directly from their local providers and healthcare organizations. Although spending on these advertisements has increased drastically during the past decades, research on their content and effects remains rare. To fill this gap, we analyzed primetime television advertisements for healthcare services directly targeting consumers. The advertisements were collected from the two largest media markets in Nevada for one month. In total, 795 advertisements were identified, and 106 of them were non-duplicates. Analysis revealed that the advertisements focused on patients’ good health outcomes by showing them smiling, going out and about, having fun with others, and enjoying rigorous physical activities. On the other hand, the advertisements focused less on the providers. Although the advertisements often showed providers in clinical settings, basic information about their professional degrees was often missing. Mentions of providers’ other qualifications and professional experiences were even scarcer. Also, a substantial number of advertisements failed to show providers interacting with patients. Additional analysis of patient and provider characteristics revealed under-representation of racial or ethnic minority and older adult patients. Representation of women and minorities as providers was even more uncommon. We discussed the implications of these findings from the perspective of patient expectation and made suggestions to help providers improve their direct-to-consumer advertisements. 
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  4. Patient-centered care and healthcare consumerism are the two most dominant ideas about the relationship between patients and providers in the United States. To identify providers’ positions between the two perspectives, we analyzed the content of direct-to-consumer healthcare service advertisements. The advertisements were collected in the state of Nevada ( N = 323) and their landing pages were analyzed for provider attributes, patient experience features, and terms referring to patients and providers. The results showed that the advertisements fully embraced the notion of patient-centeredness by commonly claiming patient-centered care and frequently using the term “patient.” The advertisements also contained multiple indicators of healthcare consumerism, although they avoided using the terms “consumer/customer/client” closely associated with consumerism. Contrary to the prominence of patient experience features, provider attributes were not common. An additional analysis of inter-specialty differences in advertising features confirmed the strong consumerism position of cosmetic surgery providers. Application of the healthcare service advertising analytic scheme developed for this study could help providers and healthcare administrators recognize how their advertising messages may reflect their values. 
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  5. null (Ed.)
    Background In the 1970s, the Federal Trade Commission declared that allowing medical providers to advertise directly to consumers would be “providing the public with truthful information about the price, quality or other aspects of their service.” However, our understanding of the advertising content is highly limited. Objective To assess whether direct-to-consumer medical service advertisements provide relevant information on access, quality and cost of care, a content analysis was conducted. Method Television and online advertisements for medical services directly targeting consumers were collected in two major urban centres in Nevada, USA, identifying 313 television advertisements and 200 non-duplicate online advertisements. Results Both television and online advertisements reliably conveyed information about the services provided and how to make an appointment. At the same time, less than half of the advertisements featured insurance information and hours of operation and less than a quarter of them contained information regarding the quality and price of care. The claims of quality were substantiated in even fewer advertisements. The scarcity of quality and cost information was more severe in television advertisements. Conclusion There is little evidence that medical service advertising, in its current form, would contribute to lower prices or improved quality of care by providing valuable information to consumers. 
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  6. Abstract Traits underlie organismal responses to their environment and are essential to predict community responses to environmental conditions under global change. Species differ in life‐history traits, morphometrics, diet type, reproductive characteristics and habitat utilization.Trait associations are widely analysed using phylogenetic comparative methods (PCM) to account for correlations among related species. Similarly, traits are measured for some but not all species, and missing continuous traits (e.g. growth rate) can be imputed using ‘phylogenetic trait imputation’ (PTI), based on evolutionary relatedness and trait covariance. However, PTI has not been available for categorical traits, and estimating covariance among traits without ecological constraints risks inferring implausible evolutionary mechanisms.Here, we extend previous PCM and PTI methods by (1) specifying covariance among traits as a structural equation model (SEM), and (2) incorporating associations among both continuous and categorical traits. Fitting a SEM replaces the covariance among traits with a set of linear path coefficients specifying potential evolutionary mechanisms. Estimated parameters then represent regression slopes (i.e. the average change in trait Y given an exogenous change in trait X) that can be used to calculate both direct effects (X impacts Y) and indirect effects (X impacts Z and Z impacts Y).We demonstrate phylogenetic structural‐equation mixed‐trait imputation using 33 variables representing life history, reproductive, morphological, and behavioural traits for all >32,000 described fishes worldwide. SEM coefficients suggest that one degree Celsius increase in habitat is associated with an average 3.5% increase in natural mortality (including a 1.4% indirect impact that acts via temperature effects on the growth coefficient), and an average 3.0% decrease in fecundity (via indirect impacts on maximum age and length). Cross‐validation indicates that the model explains 54%–89% of variance for withheld measurements of continuous traits and has an area under the receiver‐operator‐characteristics curve of 0.86–0.99 for categorical traits.We use imputed traits to classify all fishes into life‐history types, and confirm a phylogenetic signal in three dominant life‐history strategies in fishes. PTI using phylogenetic SEMs ensures that estimated parameters are interpretable as regression slopes, such that the inferred evolutionary relationships can be compared with long‐term evolutionary and rearing experiments. 
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