Ancient DNA Reconstructs the Genetic Legacies of Precontact Puerto Rico Communities.

Indigenous peoples have occupied the island of Puerto Rico since at least 3000 BC. Due to the demographic shifts that occurred after European contact, the origin(s) of these ancient populations, and their genetic relationship to present-day islanders, are unclear. We use ancient DNA to characterize the population history and genetic legacies of precontact Indigenous communities from Puerto Rico. Bone, tooth, and dental calculus samples were collected from 124 individuals from three precontact archaeological sites: Tibes, Punta Candelero, and Paso del Indio. Despite poor DNA preservation, we used target enrichment and high-throughput sequencing to obtain complete mitochondrial genomes (mtDNA) from 45 individuals and autosomal genotypes from two individuals. We found a high proportion of Native American mtDNA haplogroups A2 and C1 in the precontact Puerto Rico sample (40% and 44%, respectively). This distribution, as well as the haplotypes represented, supports a primarily Amazonian South American origin for these populations and mirrors the Native American mtDNA diversity patterns found in present-day islanders. Three mtDNA haplotypes from precontact Puerto Rico persist among Puerto Ricans and other Caribbean islanders, indicating that present-day populations are reservoirs of precontact mtDNA diversity. Lastly, we find similarity in autosomal ancestry patterns between precontact individuals from Puerto Rico and the Bahamas, suggesting a shared component of Indigenous Caribbean ancestry with close affinity to South American populations. Our findings contribute to a more complete reconstruction of precontact Caribbean population history and explore the role of Indigenous peoples in shaping the biocultural diversity of present-day Puerto Ricans and other Caribbean islanders.

A connectionist modeling study of the neural mechanisms underlying pain's ability to reorient attention.

Connectionist modeling was used to investigate the brain mechanisms responsible for pain's ability to shift attention away from another stimulus modality and toward itself. Different connectionist model architectures were used to simulate the different possible brain mechanisms underlying this attentional bias, where nodes in the model simulated the brain areas thought to mediate the attentional bias, and the connections between the nodes simulated the interactions between the brain areas. Mathematical optimization techniques were used to find the model parameters, such as connection strengths, that produced the best quantitative fits of reaction time and event-related potential data obtained in our previous work. Of the several architectures tested, two produced excellent quantitative fits of the experimental data. One involved an unexpected pain stimulus activating somatic threat detectors in the dorsal posterior insula. This threat detector activity was monitored by the medial prefrontal cortex, which in turn evoked a phasic response in the locus coeruleus. The locus coeruleus phasic response resulted in a facilitation of the cortical areas involved in decision and response processes time-locked to the painful stimulus. The second architecture involved the presence of pain causing an increase in general arousal. The increase in arousal was mediated by locus coeruleus tonic activity, which facilitated responses in the cortical areas mediating the sensory, decision, and response processes involved in the task. These two neural network architectures generated competing predictions that can be tested in future studies.

Experimental design of diffusion and desorption of contaminant in heterogeneous media.

Storage of contaminants in low permeability media (LPM) presents a great challenge for prediction of remediation effectiveness and efficiency. The reason lies in the contaminants' complex behaviors within heterogeneous media. Both interparticle and intraparticle diffusion contribute to the difficulty of precise site assessment. Sorption of contaminants--especially within LPM--may sequester the contaminants from active treatment, while desorption over a long period of time leads to contaminant release from storage and consequent re-contamination. Research has been conducted toward better understanding of contaminant diffusion and sorption/desorption processes to better predict contaminant response to site treatment. However, most of the research has been carried out within homogeneous media, while real scenarios in environmental problems feature media whose permeability and other characteristics vary significantly over the treatment volume. Further, few efforts have combined the interparticle/intraparticle diffusion and sorption/desorption processes together. This research aims at a feasible experimental design of diffusion and desorption of contaminant in heterogeneous media to address the gaps in previous research. A 2-D experimental system was designed to evaluate interparticle/intraparticle diffusion processes of trichloroethylene (TCE) in heterogeneous media. The 2-D system was modified to include organic matter in media for simulation of sorption/desorption processes. Results of the research will improve the understanding of how these different transport processes act together within heterogeneous media. Results will also allow for the evaluation of the impact of contaminant mass transport from within low permeability media at a potential treatment site and can support the development of mathematical tools/models combining interparticle/intraparticle and sorption/desorption processes. Such a model will promote more accurate site assessment and provide more confidence in the choice of an effective, economically optimized remediation strategy.

Estimating the resuspension rate and residence time of indoor particles.

Resuspension experiments were performed in a single-family residence. Resuspension by human activity was found to elevate the mass concentration of indoor particulate matter with an aerodynamic diameter less than 10 microm (PM10) an average of 2.5 times as high as the background level. As summarized from 14 experiments, the average estimated PM10 resuspension rate by a person walking on a carpeted floor was (1.4 +/- 0.6) x 10(-4) hr(-1). The estimated residence time for PM in the indoor air following resuspension was less than 2 hr for PM10 and less than 3 hr for 2-microm tracer particles. However, experimental results show that the 2-microm tracer particles stayed in the combined indoor air and surface compartments much longer (>>19 days). Using a two-compartment model to simulate a regular deposition and resuspension cycle by normal human activity (e.g., walking and sitting on furniture), we estimated residence time for 2-microm conservative particulate pollutants to be more than 7 decades without vacuum cleaning, and months if vacuum cleaning was done once per week. This finding supports the observed long residence time of persistent organic pollutants in indoor environments. This study introduces a method to evaluate the particle resuspension rate from semicontinuous concentration data of particulate matter (PM). It reveals that resuspension and subsequent exfiltration does not strongly affect the overall residence time of PM pollutants when compared with surface cleaning. However, resuspension substantially increases PM concentration, and thus increases short-term inhalation exposure to indoor PM pollutants.

Impact of Electronic Physician Order-Set on Antibiotic Ordering Time in Septic Patients in the Emergency Department.

BACKGROUND: Sepsis is a serious medical condition that can lead to organ dysfunction and death. Research shows that each hour delay in antibiotic administration increases mortality. The Surviving Sepsis Campaign Bundles created standards to assist in the timely treatment of patients with suspected sepsis to improve outcomes and reduce mortality. OBJECTIVE: This article determines if the use of an electronic physician order-set decreases time to antibiotic ordering for patients with sepsis in the emergency department (ED). METHODS: A retrospective chart review was performed on adult patients who presented to the ED of four community hospitals from May to July 2016. Patients with severe sepsis and/or septic shock were included. Primary outcome was the difference in time to antibiotic ordering in patients whose physicians utilized the order-set versus those whose physicians did not. Secondary outcomes included differences in time to antibiotic administration, time to lactate test, hospital length of stay, and posthospitalization disposition. The institution's Quality Improvement Committee approved the project. RESULTS: Forty-five of 123 patients (36.6%) with sepsis had physicians who used the order-set. Order-set utilization reduced the mean time to ordering antibiotics by 20 minutes (99 minutes, 95% confidence interval [CI]: 69-128 vs. 119 minutes, 95% CI: 91-147), but this finding was not statistically significant. Mean time to antibiotic administration (145 minutes, 95% CI: 108-181 vs. 182 minutes, 95% CI: 125-239) and median time to lactate tests (12 minutes, 95% CI: 0-20 vs. 19 minutes, 95% CI: 8-34), although in the direction of the hypotheses, were not significantly different. CONCLUSION: Utilization of the order-set was associated with a potentially clinically significant, but not statistically significant, reduced time to antibiotic ordering in patients with sepsis. Electronic order-sets are a promising tool to assist hospitals with meeting the Centers for Medicare and Medicaid Services core measure.

Intravenous antibiotics for chronic rhinosinusitis: are they effective?

PURPOSE OF REVIEW: Antibiotics have been used commonly in chronic rhinosinusitis, often because chronic rhinosinusitis has features of a prolonged bacterial sinusitis, including abnormal CT findings and positive bacterial cultures. The advent of peripherally inserted central catheters has enabled outpatient parenteral antibiotic therapy to become a convenient means of delivering potent antibiotics for various conditions when oral antibiotics may not be effective or appropriate. Chronic rhinosinusitis has been included as a condition that may benefit from outpatient parenteral antibiotic therapy; however, there are few studies that document its success and, furthermore, chronic rhinosinusitis may not always be an infectious process. RECENT FINDINGS: Three recent uncontrolled retrospective studies examined outpatient parenteral antibiotic therapy in chronic rhinosinusitis. In one series outpatient parenteral antibiotic therapy was used as an adjunct to sinus surgery, in another it was used as an alternative to sinus surgery in the pediatric population, and in the third it was used as temporary resolution for adult patients who had failed other therapies including sinus surgery. Short-term success rates were reported in the range of 29 to 89%, but relapse rates were as high as 89%. Complication rates in theses studies ranged from 14 to 26%, including medication reactions and intravenous line problems. SUMMARY: The role of outpatient parenteral antibiotic therapy in the treatment of chronic rhinosinusitis has not been universally established. Although outpatient parenteral antibiotic therapy may have a role in avoiding sinus surgery in select pediatric populations, the contribution to a lasting resolution in adult patients is less clear and there are possible complications. Recognizing subsets of chronic rhinosinusitis patients for whom outpatient parenteral antibiotic therapy is appropriate will be the challenge for the future.

Spatial patterns and temporal trends in mercury concentrations, precipitation depths, and mercury wet deposition in the North American Great Lakes region, 2002-2008.

Annual and weekly mercury (Hg) concentrations, precipitation depths, and Hg wet deposition in the Great Lakes region were analyzed by using data from 5 monitoring networks in the USA and Canada for a 2002-2008 study period. High-resolution maps of calculated annual data, 7-year mean data, and net interannual change for the study period were prepared to assess spatial patterns. Areas with 7-year mean annual Hg concentrations higher than the 12 ng per liter water-quality criterion were mapped in 4 states. Temporal trends in measured weekly data were determined statistically. Monitoring sites with significant 7-year trends in weekly Hg wet deposition were spatially separated and were not sites with trends in weekly Hg concentration. During 2002-2008, Hg wet deposition was found to be unchanged in the Great Lakes region and its subregions. Any small decreases in Hg concentration apparently were offset by increases in precipitation.

"The wholeness of things": infusing diversity and social justice into death education.

This article presents resources and strategies for the infusion of diversity and social justice themes into an undergraduate death and dying course. The intent is not to replace or dismiss existing thanatological insights and debates, but rather to widen the cultural perspective to bring these insights and debates into conversation with multiple ways of perceiving and understanding. The article covers definitions, goals and rationales, challenges in identifying and developing appropriate resources, and overall course design. It also explores readings, audiovisual materials, class activities, and pedagogical approaches to foster: student engagement with diverse world-views and experiences; understanding of "cultural competence" in various fields; awareness of the impact of race, class, gender, etc., on access to resources and care; commitment to activism for social justice; and exposure to many forms of resilience, meaning-making, and creative healing.