Publications by authors named "O'Hara T"

The triboelectric charging of granular material is a long-standing and poorly understood phenomenon, with numerous scientific and industrial applications ranging from volcanic lightning to pharmaceutical production. The most widely utilised apparatus for the study of such charging is the Faraday cup, however, existing analysis of the resulting measurements is often simplistic and fails to distinguish charging due to particle-particle interactions from charging occurring through other mechanisms. Here, we outline a modular approach for interpreting these measurements, enabling triboelectric phenomena to be explored in greater detail.

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  • The study analyzes how factors like location, age, diet, and metabolism affect the concentration of essential and non-essential elements in Steller sea lion pups from different Aleutian Islands rookeries.
  • Differences in element concentrations, like higher mercury in one rookery and higher sulfur in another, were found, indicating locality impacts wildlife health.
  • The research revealed strong interactions among elements in lanugo, suggesting that these relationships are important for understanding the health and metabolism of sea lion pups.
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  • The brooding brittle-star is a simultaneous hermaphrodite with a complex genetic structure, showing multiple divergent mitochondrial DNA lineages and high levels of inbreeding.
  • Research using exon-capture and transcriptome data reveals that its nuclear genome contains various expressed components across distinct samples, indicating significant genetic diversity.
  • The findings suggest that this brittle-star may be a hybrid polyploid organism with unique reproductive strategies, marking the first discovery of such a complex in the Echinodermata phylum.
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Introduction: Recommendations for chaperone use during sensitive exams have been left mostly to individual institutions, despite a paucity of data providing guidance. The purpose of this study was to survey patients and medical providers on their attitudes toward chaperone use and explore factors that may influence these attitudes.

Materials And Methods: A survey was administered at a single tertiary military medical center to providers and patients across multiple specialties, and further sub-analysis of the data were completed.

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Steller sea lions (SSL) are sentinels for monitoring environmental contaminants in remote areas of the Aleutian Islands, Alaska. Therefore, concentrations of several organochlorines (OCs) were measured in blood from 123 SSL pups sampled from 3 regions; the western Aleutian Islands (WAI), central Aleutian Islands (CAI), and the central Gulf of Alaska. Blood, blubber, and milk from 12 adult female SSL from WAI, CAI and southeast Alaska also were analyzed.

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Wheat blast, caused by the fungus Magnaporthe oryzae, threatens global cereal production since its emergence in Brazil in 1985 and recently spread to Bangladesh and Zambia. Here we demonstrate that the AVR-Rmg8 effector, common in wheat-infecting isolates, is recognized by the gene Pm4, previously shown to confer resistance to specific races of Blumeria graminis f. sp.

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Harnessing genetic diversity in major staple crops through the development of new breeding capabilities is essential to ensure food security. Here we examined the genetic and phenotypic diversity of the A. E.

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The Ophiuroidea is the most speciose class of echinoderms and has the greatest diversity of larval forms, but we know less about the evolution of development (evo-devo) in this group than for the other echinoderm classes. As is typical of echinoderms, evo-devo in the Ophiuroidea resulted in the switch from production of small eggs and feeding (planktotrophic) larvae to large eggs and non-feeding (lecithotrophic) larvae. Parental care (ovoviviparity or viviparity/matrotrophy) is the most derived life history.

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Mercury is a global contaminant that bioaccumulates in a tissue-specific manner in long-lived predators such as Steller sea lions (SSL). Bone is a well-preserved material amenable for studying millennial scale trends; however, little is known about the distribution and variability of total mercury concentrations ([THg]) within individual bones and among bone elements in SSL. We assessed SSL bone [THg] variability with respect to physiologic age, bone type, longitudinally within a bone, and among bone elements.

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Introduction: Pancreatic surgery is technically challenging, with mortality rates at high-volume centers ranging from 0% to 5%. An inverse relationship between surgeon volume and perioperative mortality has been reported suggesting that patients benefit from experienced surgeons at high-volume centers. There is little published on the volume of pancreatic surgeries performed in military treatment facilities (MTF) and there is no centralization policy regarding pancreatic surgery.

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Geographic differences in population growth trends are well-documented in Steller sea lions (), a species of North Pacific pinniped listed under the U.S. Endangered Species Act in 1990 following a marked decline in population abundance that began during the 1970s.

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Total mercury ([THg]) and selenium ([TSe]) concentrations were determined in California sea lion (Zalophus californianus) lanugo from the Gulf of California in 2021 and 2022. Relationships with sex, morphometrics, and year were evaluated. Following toxicological thresholds of concern for piscivorous mammals, most pups had a [THg] < 10 ppm, one pup (2021) had a [THg] > 20 ppm, no pups had a [THg] > 30 ppm.

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Total mercury concentrations ([THg]) exceed thresholds of concern in some Steller sea lion (Eumetopias jubatus) tissues from certain portions of the Aleutian Islands, Alaska. We applied compound-specific stable isotope analyses of both carbon and nitrogen in amino acids from fish muscle tissue to quantify the proportional contributions of primary production sources and trophic positions of eight prey species (n = 474 total) that are part of Steller sea lion diets. Previous THg analyses of fish muscle, coupled with monomethylmercury analyses of a subset of samples, substantiated previous findings that fishes from the west of Amchitka Pass, a discrete oceanographic boundary of the Aleutian Archipelago, have higher muscle Hg concentrations relative to fishes from the east.

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Arctic lamprey (Lethenteron camtschaticum) is an important dietary resource for rural and indigenous communities in parts of Alaska, with some commercial use. As with many fish species harvested for human consumption, there are concerns regarding mercury concentrations ([Hg]) in Arctic lamprey that may impact human health. To date, information regarding the life cycle and diet of Arctic lamprey is scarce, with no published studies examining [Hg] in Arctic lamprey tissues.

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Rapid and effective quantification of total mercury concentrations ([THg]) in fish muscle is an important part of ongoing monitoring to provide reliable and near real-time public health guidance. Methods for quantifying THg in fish muscle frequently require the use of large sample mass and numerous preparation steps. Wet (aka fresh weight) biopsy punch samples of fish muscle have been used to quantify THg directly, without drying and homogenization.

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Background: The purpose of this study is to evaluate the trends of hepatobiliary surgeries performed at military hospitals and to discuss potential implications on resident training and military readiness. While there is data to suggest centralization of surgical specialty services leads to improved patient outcomes, the military does not currently have a specific centralization policy. Implementation of such a policy could potentially impact resident training and readiness of military surgeons.

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Rationale: Flask-shaped invaginations of the cardiomyocyte sarcolemma called caveolae require the structural protein caveolin-3 (Cav-3) and host a variety of ion channels, transporters, and signaling molecules. Reduced Cav-3 expression has been reported in models of heart failure, and variants in CAV3 have been associated with the inherited long-QT arrhythmia syndrome. Yet, it remains unclear whether alterations in Cav-3 levels alone are sufficient to drive aberrant repolarization and increased arrhythmia risk.

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Since emerging in Brazil in 1985, wheat blast has spread throughout South America and recently appeared in Bangladesh and Zambia. Here we show that two wheat resistance genes, Rwt3 and Rwt4, acting as host-specificity barriers against non-Triticum blast pathotypes encode a nucleotide-binding leucine-rich repeat immune receptor and a tandem kinase, respectively. Molecular isolation of these genes will enable study of the molecular interaction between pathogen effector and host resistance genes.

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There is a growing interest in the exploitation of deep-sea mineral deposits, particularly on the abyssal seafloor of the central Pacific Clarion-Clipperton Zone (CCZ), which is rich in polymetallic nodules. In order to effectively manage potential exploitation activities, a thorough understanding of the biodiversity, community structure, species ranges, connectivity, and ecosystem functions across a range of scales is needed. The benthic megafauna plays an important role in the functioning of deep-sea ecosystems and represents an important component of the biodiversity.

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This research demonstrates how the use of high-resolution rain-gauge data for quality control (QC) significantly changes extreme rainfall estimates, with implications in scientific, meteorological and engineering applications. Current open QC algorithms only consider data at hourly or daily accumulations. Here we present the first open QC algorithm utilising sub-hourly rain-gauge data from official networks at a national, multi-decade scale.

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Background: Breast conservation therapy (BCT) is frequently performed for breast cancer and associated with a significant risk for positive margins. Intraoperative three-dimensional (3-D) tomosynthesis potentially could limit the risk of positive margins.

Methods: Retrospective review of an institutional breast cancer registry.

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Introduction: The National Defense Authorization Act of 2017 indicated the need for a national strategy to improve trauma care among military treatment facilities (MTFs). Part of the proposed strategy to improve trauma outcomes was to convert identified MTFs into verified trauma centers. The American College of Surgeons (ACS) verifies trauma centers through an evaluation process based on available resources at a facility.

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Introduction: Managing postoperative pain requires an individualized approach in order to balance adequate pain control with risk of persistent opioid use and narcotic abuse associated with inappropriately outsized narcotic prescriptions. Shared decision-making has been proposed to address individual pain management needs. We report here the results of a quality improvement initiative instituting prescribing guidelines using shared decision-making and preoperative pain expectation and management education to decrease excess opioid pills after surgery and improve patient satisfaction.

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  • People with rarer dementias struggle to find support and tailored information, but online meeting platforms can help them connect, especially during the COVID-19 pandemic.
  • The study focuses on creating videoconferencing support groups for individuals with frontotemporal dementia, young-onset Alzheimer’s, and other conditions, detailing the process of development, testing, and evaluation.
  • A three-phase approach was used to gather input from affected individuals, test the support groups with 154 participants, and develop an evaluation plan to refine future sessions based on gathered data and themes.
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Arctic Indigenous Peoples are among the most exposed humans when it comes to foodborne mercury (Hg). In response, Hg monitoring and research have been on-going in the circumpolar Arctic since about 1991; this work has been mainly possible through the involvement of Arctic Indigenous Peoples. The present overview was initially conducted in the context of a broader assessment of Hg research organized by the Arctic Monitoring and Assessment Programme.

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