1,666 research outputs found

    Specialization or Diversification? A Basic Policy Decision Confronting Economically Underdeveloped Countries

    Get PDF
    Paper delivered before the Historical Society of the Rice Institute on May 8, 195

    The effects of fire on burrow-nesting seabirds particularly short-tailed shearwaters (Puffinus tenuirostris) and their habitat in Tasmania

    Get PDF
    The synchronised breeding habit of many seabird species makes them particularly vulnerable to fires in the nesting area. Post-fire recolonisation and soil formation were studied on Albatross Island, and observations from island rookeries of shearwaters, fairy prions and fairy penguins in eastern Bass Strait and elsewhere were used with a view to understanding the long-term impact of fires on seabird colonies in Tasmania

    Bathymetric terrain model of the Atlantic margin for marine geological investigations.

    Get PDF
    Bathymetric terrain models of seafloor morphology are an important component of marine geological investigations. Advances in acquisition and processing technologies of bathymetric data have facilitated the creation of high-resolution bathymetric surfaces that approach the resolution of similar surfaces available for onshore investigations. These bathymetric terrain models provide a detailed representation of the Earth’s subaqueous surface and, when combined with other geophysical and geological datasets, allow for interpretation of modern and ancient geological processes. The purpose of the bathymetric terrain model presented in this report is to provide a high-quality bathymetric surface of the Atlantic margin of the United States that can be used to augment current and future marine geological investigations. The input data for this bathymetric terrain model, covering almost 305,000 square kilometers, were acquired by several sources, including the U.S. Geological Survey, the National Oceanic and Atmospheric Administration National Geophysical Data Center and the Ocean Exploration Program, the University of New Hampshire, and the Woods Hole Oceanographic Institution. These data have been edited using hydrographic data processing software to maximize the quality, usability, and cartographic presentation of the combined terrain model

    Epidemiology, Microbiology, and Clinical Outcomes Among Patients With Intravenous Drug Use-Associated Infective Endocarditis in New Brunswick

    Get PDF
    Background: Within the context of Canada’s opioid crisis, medical complications associated with intravenous drug use (IVDU) are increasing. Infective endocarditis (IE) is a serious complication of IVDU, and understanding the characteristics of these patients could aid health systems, clinicians, and patients in the optimization of treatment and prevention of IVDU-IE. / Methods: At a tertiary care hospital in southern New Brunswick, we conducted a retrospective chart review to identify patients with IVDU-IE admitted between January 1, 2013, and December 31, 2017. We collected data related to the epidemiology, microbiology, clinical manifestations, echocardiography, complications during hospital admission, and outcomes. / Results: Forty-two cases of IVDU-IE met inclusion criteria. The rate of IVDU-IE increased from 2.28 per 100,000 population in 2014 to 4.00 in 2017, which, although not statistically significant, reflects patterns in other jurisdictions. Most patients (72.4%) were male, and the mean age was 38.3 (±11.5) years. Most patients (79.3%) injected opioids. The most common clinical sign was fever (90.5%), and Staphylococcus aureus (61.9%) was the most common microorganism. The tricuspid valve was most commonly infected (58.5%), 50% of cases had heart failure as a complication during admission, and 45.2% of cases required valve replacement or repair. The 2-year survival rate after admission for initial IVDU-IE episode was 62.0% (95% confidence interval: 36.5-79.7). / Conclusion: IVDU-IE is common in New Brunswick and may be increasing. Despite the relatively young age of this patient population, IVDU-IE is associated with significant morbidity and mortality. Expanding effective harm reduction and addiction treatment strategies for this cohort is recommended. // Contexte: Dans le contexte de la crise des opioïdes au Canada, les complications médicales liées à l'utilisation de drogues par voie intraveineuse (UDIV) sont en augmentation. L'endocardite infectieuse (EI) est une complication grave de l'UDIV, et la compréhension des caractéristiques de ces patients pourrait aider les systèmes de santé, les cliniciens et les patients à optimiser le traitement et la prévention de l’EI liée à l’UDIV (EI-UDIV). / Méthodes: Dans un hôpital de soins tertiaires du sud du Nouveau-Brunswick, nous avons effectué un examen rétrospectif des dossiers afin d'identifier les patients atteints de l’EI-UDIV admis entre le 1er janvier 2013 et le 31 décembre 2017. Nous avons recueilli des données relatives à l'épidémiologie, la microbiologie, les manifestations cliniques, l'échocardiographie, les complications lors de l'admission à l'hôpital et les bilans. / Résultats: Quarante-deux cas d'EI-UDIV ont répondu aux critères d'inclusion. Le taux d'EI-UDIV est passé de 2,28 pour 100 000 habitants en 2014 à 4,00 en 2017, ce qui, bien que non significatif statistiquement, reflète les tendances observées dans d'autres juridictions. La plupart des patients (72,4 %) étaient des hommes, et l'âge moyen était de 38,3 ans (±11,5). La plupart des patients (79,3 %) s'injectaient des opioïdes. Le signe clinique le plus fréquent était la fièvre (90,5 %), et le Staphylococcus aureus (61,9 %) était le micro-organisme le plus couramment observé. La valve tricuspide était le plus souvent infectée (58,5 %), 50 % des cas avaient une insuffisance cardiaque en tant que complication lors de l'admission, et 45,2 % des cas ont nécessité un remplacement ou une réparation de la valve. Le taux de survie à deux ans après l'admission pour l'épisode initial d'EI-UDIV était de 62,0 % (intervalle de confiance à 95 % : 36,5-79,7). / Conclusion: L'EI-UDIV est fréquent au Nouveau-Brunswick et pourrait être en augmentation. Malgré l'âge relativement jeune de cette population de patients, l'UDIV-IE est associée à une morbidité et une mortalité importantes. Il est recommandé d'étendre les stratégies efficaces de réduction des risques et de traitement des dépendances pour cette cohorte

    Genetic Variation and Antioxidant Response Gene Expression in the Bronchial Airway Epithelium of Smokers at Risk for Lung Cancer

    Get PDF
    Prior microarray studies of smokers at high risk for lung cancer have demonstrated that heterogeneity in bronchial airway epithelial cell gene expression response to smoking can serve as an early diagnostic biomarker for lung cancer. As a first step in applying functional genomic analysis to population studies, we have examined the relationship between gene expression variation and genetic variation in a central molecular pathway (NRF2-mediated antioxidant response) associated with smoking exposure and lung cancer. We assessed global gene expression in histologically normal airway epithelial cells obtained at bronchoscopy from smokers who developed lung cancer (SC, n=20), smokers without lung cancer (SNC, n=24), and never smokers (NS, n=8). Functional enrichment analysis showed that the NRF2-mediated, antioxidant response element (ARE)-regulated genes, were significantly lower in SC, when compared with expression levels in SNC. Importantly, we found that the expression of MAFG (a binding partner of NRF2) was correlated with the expression of ARE genes, suggesting MAFG levels may limit target gene induction. Bioinformatically we identified single nucleotide polymorphisms (SNPs) in putative ARE genes and to test the impact of genetic variation, we genotyped these putative regulatory SNPs and other tag SNPs in selected NRF2 pathway genes. Sequencing MAFG locus, we identified 30 novel SNPs and two were associated with either gene expression or lung cancer status among smokers. This work demonstrates an analysis approach that integrates bioinformatics pathway and transcription factor binding site analysis with genotype, gene expression and disease status to identify SNPs that may be associated with individual differences in gene expression and/or cancer status in smokers. These polymorphisms might ultimately contribute to lung cancer risk via their effect on the airway gene expression response to tobacco-smoke exposure.Intramural Research Program of the National Institute of Environmental Health Sciences; National Institutes of Health (Z01 ES100475, U01ES016035, R01CA124640

    Tsunamigenic Splay Faults Imply a Long‐Term Asperity in Southern Prince William Sound, Alaska

    Get PDF
    Coseismic slip partitioning and uplift over multiple earthquake cycles is critical to understanding upper‐plate fault development. Bathymetric and seismic reflection data from the 1964 Mw9.2 Great Alaska earthquake rupture area reveal sea floor scarps along the tsunamigenic Patton Bay/Cape Cleare/Middleton Island fault system. The faults splay from a megathrust where duplexing and underplating produced rapid exhumation. Trenchward of the duplex region, the faults produce a complex deformation pattern from oblique, south‐directed shortening at the Yakutat‐Pacific plate boundary. Spatial and temporal fault patterns suggest that Holocene megathrust earthquakes had similar relative motions and thus similar tsunami sources as in 1964. Tsunamis during future earthquakes will likely produce similar run‐up patterns and travel times. Splay fault surface expressions thus relate to plate boundary conditions, indicating millennial‐scale persistence of this asperity. We suggest structure of the subducted slab directly influences splay fault and tsunami generation landward of the frontal subduction zone prism

    Geomorphic characterization of the U.S. Atlantic continental margin

    Get PDF
    This paper is not subject to U.S. copyright. The definitive version was published in Marine Geology 338 (2013): 46–63, doi:10.1016/j.margeo.2012.12.008.The increasing volume of multibeam bathymetry data collected along continental margins is providing new opportunities to study the feedbacks between sedimentary and oceanographic processes and seafloor morphology. Attempts to develop simple guidelines that describe the relationships between form and process often overlook the importance of inherited physiography in slope depositional systems. Here, we use multibeam bathymetry data and seismic reflection profiles spanning the U.S. Atlantic outer continental shelf, slope and rise from Cape Hatteras to New England to quantify the broad-scale, across-margin morphological variation. Morphometric analyses suggest the margin can be divided into four basic categories that roughly align with Quaternary sedimentary provinces. Within each category, Quaternary sedimentary processes exerted heavy modification of submarine canyons, landslide complexes and the broad-scale morphology of the continental rise, but they appear to have preserved much of the pre-Quaternary, across-margin shape of the continental slope. Without detailed constraints on the substrate structure, first-order morphological categorization the U.S. Atlantic margin does not provide a reliable framework for predicting relationships between form and process.This work was funded by the USGS Mendenhall Postdoctoral Fellowship Program and the U.S. Nuclear Regulatory Commission

    Pediatric medication use experiences and patient counseling in community pharmacies: Perspectives of children and parents

    Get PDF
    AbstractObjectivesThis study aimed to explore the perspectives of children and parents regarding: 1) pediatric patients' knowledge and medication use experiences for chronic conditions; 2) how they want to learn about medicines; and 3) perceptions of community pharmacist–provided counseling.DesignQualitative study using semistructured interviews and thematic analyses.SettingThree community pharmacies in 2 eastern states: one in rural western North Carolina, and 2 in an urban region of western Pennsylvania.ParticipantsA total of 39 study participants: 20 children using medications for chronic conditions and 19 parents interviewed July-December 2015.Main outcome measuresChild and parent perspectives regarding pediatric medication use, knowledge, experiences, and pharmacist-provided patient counseling.ResultsChildren and parents had similar perspectives on pediatric medication use and pharmacist counseling experiences. Six themes emerged: 1) child's knowledge, self-management, and medication use experiences; 2) essential medication information and sources; 3) child's frequent absence from the pharmacy; 4) patient counseling needs and recommendations; 5) use of interactive technologies to facilitate learning about medicines; and 6) perceptions of pharmacists. Participants reported that children were independently managing their medications, although they had minimal knowledge about medicines. Children and parents stated that the child's absence during medication pick-up at pharmacies was a barrier to receiving counseling by pharmacists. Children were comfortable and receptive to pharmacists educating them about their medicines, particularly how medications affect the human body, how they were manufactured, and research studies on their medications. Parents and children recommended the use of interactive and educational technologies for pediatric counseling.ConclusionChildren are frequently not present at pharmacies during prescription pick-up; however, children and parents are comfortable with and receptive to pediatric medication counseling by pharmacists. Interactive and educational technologies need to be developed and used by pharmacists to facilitate counseling and educate children about the effective and safe use of medicines

    MEPicides: Potent antimalarial prodrugs targeting isoprenoid biosynthesis

    Get PDF
    AbstractThe emergence of Plasmodium falciparum resistant to frontline therapeutics has prompted efforts to identify and validate agents with novel mechanisms of action. MEPicides represent a new class of antimalarials that inhibit enzymes of the methylerythritol phosphate (MEP) pathway of isoprenoid biosynthesis, including the clinically validated target, deoxyxylulose phosphate reductoisomerase (Dxr). Here we describe RCB-185, a lipophilic prodrug with nanomolar activity against asexual parasites. Growth of P. falciparum treated with RCB-185 was rescued by isoprenoid precursor supplementation, and treatment substantially reduced metabolite levels downstream of the Dxr enzyme. In addition, parasites that produced higher levels of the Dxr substrate were resistant to RCB-185. Notably, environmental isolates resistant to current therapies remained sensitive to RCB-185, the compound effectively treated sexually-committed parasites, and was both safe and efficacious in malaria-infected mice. Collectively, our data demonstrate that RCB-185 potently and selectively inhibits Dxr in P. falciparum, and represents a promising lead compound for further drug development.</jats:p
    corecore