11 research outputs found
Quantifying Nearshore Sea Turtle Densities: Applications of Unmanned Aerial Systems for Population Assessments
Although sea turtles face significant pressure from human activities, some populations are recovering due to conservation programs, bans on the trade of turtle products, and reductions in bycatch. While these trends are encouraging, the status of many populations remains unknown and scientific monitoring is needed to inform conservation and management decisions. To address these gaps, this study presents methods for using unmanned aerial systems (UAS) to conduct population assessments. Using a fixed-wing UAS and a modified strip-transect method, we conducted aerial surveys along a three-kilometer track line at Ostional, Costa Rica during a mass-nesting event of olive ridley turtles (Lepidochelys olivacea). We visually assessed images collected during six transects for sea turtle presence, resulting in 682 certain detections. A cumulative total of 1091 certain and probable turtles were detected in the collected imagery. Using these data, we calculate estimates of sea turtle density (km-2) in nearshore waters. After adjusting for both availability and perception biases, we developed a low-end estimate of 1299â±â458 and a high-end estimate of 2086â±â803 turtles per km-2. This pilot study illustrates how UAS can be used to conduct robust, safe, and cost-effective population assessments of sea turtle populations in coastal marine ecosystems
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An Analysis of the Characteristics of Robert Schumann's Piano Works
The primary purpose of this thesis is to give the prospective performer of Schumann's piano works a better understanding of his many works for the piano and to give the pianist, and musicians in general, a better understanding of the pianistic devices employed by Schumann in his works for this instrument. Schumann rose to great heights for short intervals. He possessed enthusiasm, humor, charm, and eloquence. Such qualities have kept his music alive and have provided his listeners with lasting pleasure. Much of his music represents the nobility and warm-heartedness that characterized early Romanticism at its best
Author Correction: Quantifying Nearshore Sea Turtle Densities: Applications of Unmanned Aerial Systems for Population Assessments
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper
Role of protein kinase C ÎČ and vascular endothelial growth factor receptor in malignant pleural mesothelioma: Therapeutic implications and the usefulness of Caenorhabditis elegans model organism
Purpose: To examine the role of both protein kinase C (PKC)-ÎČ and vascular endothelial growth factor receptor (VEGFR)-2 in malignant pleural mesothelioma (MPM) using respective inhibitors, enzastaurin and KRN633. Materials and Methods: MPM cell lines, control cells, and a variety of archived MPM tumor samples were used to determine the protein expression levels of PKC-ÎČ, VEGFR-2, VEGF, and p-AKT. Effects of enzastaurin and KRN633 on phosphorylation status of key signaling molecules and viability of the mesothelioma cells were determined. The common soil nematode, Caenorhabditis elegans, was treated with enzastaurin to determine its suitability to screen for highly potent kinase inhibitors. Results: PKC-ÎČ1, PKC-ÎČ2 and VEGFR-2/KDR were overexpressed in MPM cell lines and MPM tumor tissues. Enzastaurin treatment resulted in significant loss in viability of VEGF induced cell proliferation; however, the effect of KRN633 was much less. Enzastaurin also dramatically decreased the phosphorylation of PKC-ÎČ, its downstream target p-AKT, and surprisingly, the upstream VEGFR-2. The combination of the two drugs at best was additive and similar results were obtained with respect to cell viability. Treatment of C. elegans with enzastaurin resulted in clear phenotypic changes and the worms were hypermotile with abnormal pattern and shape of eggs, suggesting altered fecundity. Conclusions: PKC-ÎČ1 and VEGFR-2 are both excellent therapeutic targets in MPM. Enzastaurin was better at killing MPM cells than KRN633 and the combination lacked synergy. In addition, we show here that C. elegans can be used to screen for the next generation inhibitors as treatment with enzastaurin resulted in clear phenotypic changes that could be assayed
A Petition for the Establishment of a Chapter of the Society of the Sigma Xi at the U.S. Naval Postgraduate School
A petition to the President of the Executive Committee and members of Sigma XI by NPS members organized as a Club to establish a Chapter at the U.S. Naval Postgraduate School.Approved for public release; distribution is unlimited
Risk of COVID-19 after natural infection or vaccinationResearch in context
Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7â15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05â0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01â0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health