The Whitham equation is a non-local, nonlinear partial differential equation that models the temporal evolution of spatial profiles of surface displacement of water waves. However, many laboratory and field measurements record time series at fixed spatial locations. To directly model data of this type, it is desirable to have equations that model the spatial evolution of time series. The spatial Whitham (sWhitham) equation, proposed as the spatial generalization of the Whitham equation, fills this need. In this paper, we study this equation and apply it to water-wave experiments on shallow and deep water. We compute periodic travelling-wave solutions to the sWhitham equation and examine their properties, including their stability. Results for small-amplitude solutions align with known results for the Whitham equation. This suggests that the systems are consistent in the weakly nonlinear regime. At larger amplitudes, there are some discrepancies. Notably, the sWhitham equation does not appear to admit cusped solutions of maximal wave height. In the second part, we compare predictions from the temporal and spatial Korteweg–de Vries and Whitham equations with measurements from laboratory experiments. We show that the sWhitham equation accurately models measurements of tsunami-like waves of depression, waves of elevation, and solitary waves on shallow water. Its predictions also compare favourably with experimental measurements of waves of depression and elevation on deep water. Accuracy is increased by adding a phenomenological damping term. Finally, we show that neither the sWhitham nor the temporal Whitham equation accurately models the evolution of wave packets on deep water.

American Indians and Alaska Natives suffer from disproportionately high rates of chronic mental and physical health conditions. These health inequities are linked to colonization and its downstream consequences. Most of the American Indian and Alaska Native health inequities research uses a deficit framework, failing to acknowledge the resilience of American Indian and Alaska Native people despite challenging historical and current contexts. This scoping review is based on a conceptual model which acknowledges the context of colonization and its consequences (psychological and health risk factors). However, rather than focusing on health risk, we focus on protective factors across three identified domains (social, psychological, and cultural/spiritual), and summarize documented relationships between these resilience factors and health outcomes. Based on the scoping review of the literature, we note gaps in extant knowledge and recommend future directions. The findings summarized here can be used to inform and shape future interventions which aim to optimize health and well-being in American Indian and Alaska Native peoples.

Within the extensive literature on international regionalism, the more limited academic work done on regional financial organizations (RFOs) tends to assume that, by pooling resources to address such common international economic issues as development funding and financial crises, RFOs contribute to economic stability in their parts of the global landscape. Although South America has led the pack in creating such RFOs, their effectiveness is limited by the asymmetry in economic heft of the continent's governments. Rather than weighing the significance of financial regionalism in South America from the point of view of the majority, we assess whether and how this phenomenon has contributed to Brazil's politico-economic rise to near-major-power standing on the world stage in the twenty-first century. Drawing on extensive interviews with Brazilian officials conducted in March 2013, we analyze three instances of South America's international public finance: development lending, crisis lending, and payment systems. Our findings suggest that self-generated unilateral and bilateral financial initiatives have brought Brasília far more significant economic and political results than have RFOs, whose various incarnations have yielded the continental giant few economic and only minor political gains.

I have been thinking a lot about environmental pedagogy in American studies, especially since I started teaching a third-year interdisciplinary course, Climate Change & Culture Wars, which focusses on the post-1970s US. I wanted to know more about how others are approaching the topic as we face up to looming climate and ecological collapse. University teachers and learners across disciplines are reckoning with it, but what's going on in American studies in Britain, and what can we learn from each other and from teachers elsewhere? How is the crisis impacting on the framing of our disciplinary fields and how are we incorporating its intellectual and practical demands into pedagogic spaces and syllabi?

Throughout their 250 Myr history, archosaurian reptiles have exhibited a wide array of body sizes, shapes, and locomotor habits, especially in regard to terrestriality. These features make Archosauria a useful clade with which to study the interplay between body size, shape, and locomotor behavior, and how this interplay may have influenced locomotor evolution. Here, digital volumetric models of 80 taxa are used to explore how mass properties and body proportions relate to each other and locomotor posture in archosaurs. One-way, nonparametric, multivariate analysis of variance, based on the results of principal components analysis, shows that bipedal and quadrupedal archosaurs are largely distinguished from each other on the basis of just four anatomical parameters (p < 0.001): mass, center of mass position, and relative forelimb and hindlimb lengths. This facilitates the development of a quantitative predictive framework that can help assess gross locomotor posture in understudied or controversial taxa, such as the crocodile-line Batrachotomus (predicted quadruped) and Postosuchus (predicted biped). Compared with quadrupedal archosaurs, bipedal species tend to have relatively longer hindlimbs and a more caudally positioned whole-body center of mass, and collectively exhibit greater variance in forelimb lengths. These patterns are interpreted to reflect differing biomechanical constraints acting on the archosaurian Bauplan in bipedal versus quadrupedal groups, which may have shaped the evolutionary histories of their respective members.

Background: Transmission of carbapenemase-producing organisms (CPO) threatens patient safety in healthcare facilities. As a result of a 2011 outbreak of blaKPC+ Klebsiella pneumoniae, the NIH Clinical Center (NIHCC) has prioritized early detection and isolation of CPO carriers, using point-prevalence surveys and targeted high-risk ward surveillance since 2011 and admission surveillance since 2013. We describe our experience over 6 years of admission surveillance. Methods: The NIHCC is a 200-bed research hospital that provides care for a highly immunocompromised patient population. From September 2013 to September 2019, perirectal swabs were ordered automatically for all patients on admission to nonbehavioral health wards. Swabs were ordered twice weekly for ICU patients, weekly in other high-risk wards, and monthly for hospital-wide point prevalence (excluding behavioral health). Patients hospitalized in the United States in the previous week or abroad in the previous 6 months were considered high risk for carriage and isolated pending results from 2 swabs. Most swabs (n = 37,526) were cultured onto HardyCHROM CRE. If gram-negative bacilli (GNB) were present, a molecular screen for carbapenemases was performed on a sweep of cultured material (day 1) pending organism isolation. GNB were identified by MALDI-TOF MS. Prior to June 2019, isolates were screened by blaKPC/blaNDM PCR. Starting in June 2019, Enterobacteriaceae and Pseudomonas aeruginosa were screened using the phenotypic modified carbapenem inactivation method (mCIM), reflexing to the GeneXpert CARBA-R molecular assay if positive; other GNB were tested directly with CARBA-R. Selected GNB underwent susceptibility testing (Sensititre). Whole-genome sequencing was used to assess relatedness among CPO isolates. Swabs from high-risk patients were tested directly by blaKPC PCR (n = 699) until August 2019 (most in parallel with culture) and thereafter by CARBA-R (n = 13). Results: Among 54,188 orders for perirectal swabs, 38,238 were collected from 14,497 patients (compliance 71%). Among 33 CPO-colonized patients identified from September 2013 through September 2019, 15 were identified on admission, 6 were identified in point-prevalence surveys, 8 were identified from high-risk ward surveillance, and 4 were identified from clinical cultures. Sequencing demonstrated no relatedness among CPO isolates. Although only 1.4% of patients sampled on admission were colonized with CPO, those meeting high-risk criteria were 21 times as likely to be colonized. Conclusion: Admission surveillance for CPO identified a low rate of colonization, but it detected nearly half of known CPO-colonized NIHCC patients over the past 6 years. Modest compliance with swab collection leaves room for improvement and likely results in missed instances of colonization. Although we cannot determine its effectiveness, we view our strategy as one of several key safety measures for our highly vulnerable patient population.

Funding: None

Disclosures: None

In recent years, researchers in pre-Hispanic Central America have used new approaches that greatly amplify and enhance evidence of plants and their uses. This paper presents a case study from Puerto Escondido, located in the lower Ulúa River valley of Caribbean coastal Honduras. We demonstrate the effectiveness of using multiple methods in concert to interpret ethnobotanical practice in the past. By examining chipped-stone tools, ceramics, sediments from artifact contexts, and macrobotanical remains, we advance complementary inquiries. Here, we address botanical practices “in the home,” such as foodways, medicinal practices, fiber crafting, and ritual activities, and those “close to home,” such as agricultural and horticultural practices, forest management, and other engagements with local and distant ecologies. This presents an opportunity to begin to develop an understanding of ethnoecology at Puerto Escondido, here defined as the dynamic relationship between affordances provided in a botanical landscape and the impacts of human activities on that botanical landscape.

OBJECTIVES/SPECIFIC AIMS: To understand the mechanisms of how a non-antimicrobial can reshape a commensal microbe community to cure a ubiquitous human disease. METHODS/STUDY POPULATION: Whole genome sequencing of bacterial isolates, metabolomic investigations of previously collected skin microbe isolates from patients, and structural investigations of a protein from these skin microbes. RESULTS/ANTICIPATED RESULTS: Metabolic pathways associated with adaptation to a changing skin microenvironment, novel antimicrobial characterization, and a structural understanding of a novel nutrient acquisition protein. DISCUSSION/SIGNIFICANCE OF IMPACT: Multiple angles of this investigation are poised to improve current non-antimicrobial dermatologic treatments and they have the potential to impact microbe-related diseases in other human microenvironments.