Publications by authors named "Claire M"

Background: Diabetic foot ulcers (DFUs) are a prevalent complication of diabetes. Individuals with DFUs can experience wound-related pain, which could be nociceptive and/or neuropathic in origin, which adversely affects health-related quality of life (HRQoL).

Aim: To determine the prevalence and characteristics of DFU-related pain and its impact on HRQoL in community-dwelling individuals with active DFUs.

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Pressure Swing Distillation (PSD) is the only advanced technology that does not require the addition of third components to the system to enhance the separation of azeotropic mixtures. It outperforms homogeneous distillation for separating pressure-sensitive azeotropic mixtures. In this study, we aimed to separate methanol and toluene using the Non-Random Two-Liquid (NRTL) and Aspen Plus thermodynamic calculation models to simulate a binary homogeneous azeotropic system.

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The Permo-Triassic mass extinction was linked to catastrophic environmental changes and large igneous province (LIP) volcanism. In addition to the widespread marine losses, the Permo-Triassic event was the most severe terrestrial ecological crisis in Earth's history and the only known mass extinction among insects, but the cause of extinction on land remains unclear. In this study, high-resolution Hg concentration records and multiple-archive S-isotope analyses of sediments from the Junggar Basin (China) provide evidence of repeated pulses of volcanic-S (acid rain) and increased Hg loading culminating in a crisis of terrestrial biota in the Junggar Basin coeval with the interval of LIP emplacement.

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Background: Ebola virus (EBOV) disease (EVD) is one of the most severe and fatal viral hemorrhagic fevers and appears to mimic many clinical and laboratory manifestations of hemophagocytic lymphohistiocytosis syndrome (HLS), also known as macrophage activation syndrome. However, a clear association is yet to be firmly established for effective host-targeted, immunomodulatory therapeutic approaches to improve outcomes in patients with severe EVD.

Methods: Twenty-four rhesus monkeys were exposed intramuscularly to the EBOV Kikwit isolate and euthanized at prescheduled time points or when they reached the end-stage disease criteria.

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Despite increasing evidence that uveitis is common and consequential in survivors of Ebola virus disease (EVD), the host-pathogen determinants of the clinical phenotype are undefined, including the pathogenetic role of persistent viral antigen, ocular tissue-specific immune responses, and histopathologic characterization. Absent sampling of human intraocular fluids and tissues, these questions might be investigated in animal models of disease; however, challenges intrinsic to the nonhuman primate model and the animal biosafety level 4 setting have historically limited inquiry. In a rhesus monkey survivor of experimental Ebola virus (EBOV) infection, we observed and documented the clinical, virologic, immunologic, and histopathologic features of severe uveitis.

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The Great Oxidation Event (GOE), arguably the most important event to occur on Earth since the origin of life, marks the time when an oxygen-rich atmosphere first appeared. However, it is not known whether the change was abrupt and permanent or fitful and drawn out over tens or hundreds of millions of years. Here, we developed a one-dimensional time-dependent photochemical model to resolve time-dependent behavior of the chemically unstable transitional atmosphere as it responded to changes in biogenic forcing.

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SignificanceSulfur isotopes confirm a key role for atmospheric sulfur gases in climatic cooling, mass extinction, and the demise of dinosaurs and other global biota after the Chicxulub bolide impact at the Cretaceous-Paleogene boundary. The sulfur isotope anomalies are confined to beds containing ejecta and, in the immediately overlying sediments, are temporally unrelated to known episodes of volcanism that also bracket this event, further addressing the controversial role of the Deccan Traps in the extinction.

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Background: By 2020/1 NHS England plans to invest over 100 m to ensure that there is one clinical pharmacist post in primary care for every 30,000 patients. A recent realist review identified key questions in the literature related to the implementation of a clinical pharmacist (CP) in a general practice role. These relate to the impact of the role, perspectives on the role (patients, GPs and pharmacists), and barriers and facilitators to the implementation process.

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The hyperarid Atacama Desert is a unique Mars-analog environment with a large near-surface soil nitrate reservoir due to the lack of rainfall leaching for millennia. We investigated nitrogen (N) cycling and organic matter dynamics in this nitrate-rich terrestrial environment by analyzing the concentrations and isotopic compositions of nitrate, organic C, and organic N, coupled with microbial pathway-enzyme inferences, across a naturally occurring rainfall gradient. Nitrate deposits in sites with an annual precipitation of <10 mm carry atmospheric δN, δO, and ΔO signatures, while these values are overprinted by biological cycling in sites with >15 mm annual precipitation.

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Introduction: Accurate detection of filarial parasites in humans and vectors is essential for the implementation and evaluation of Global and National Programs to eliminate lymphatic filariasis. Immunological methods to detect infection are available; however, cross-reactivity issues have been reported in most of them. Nucleic acid-based molecular assays offer high levels of specificity and sensitivity and can be used to detect the infections.

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Over the past 150 million years, the Chilean Atacama Desert has been transformed into one of the most inhospitable landscapes by geophysical changes, which makes it an ideal Mars analog that has been explored for decades. However, a heavy rainfall that occurred in the Atacama in 2017 provides a unique opportunity to study the response of resident extremophiles to rapid environmental change associated with excessive water and salt shock. Here we combine mineral/salt composition measurements, amendment cell culture experiments, and next-generation sequencing analyses to study the variations in salts and microbial communities along a latitudinal aridity gradient of the Atacama Desert.

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With annual precipitation less than 20 mm and extreme UV intensity, the Atacama Desert in northern Chile has long been utilized as an analogue for recent Mars. In these hyperarid environments, water and biomass are extremely limited, and thus, it becomes difficult to generate a full picture of biogeochemical phosphate-water dynamics. To address this problem, we sampled soils from five Atacama study sites and conducted three main analyses-stable oxygen isotopes in phosphate, enzyme pathway predictions, and cell culture experiments.

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The inability to resolve the exact temporal relationship between two pivotal events in Earth history, the Paleoproterozoic Great Oxidation Event (GOE) and the first "snowball Earth" global glaciation, has precluded assessing causality between changing atmospheric composition and ancient climate change. Here we present temporally resolved quadruple sulfur isotope measurements (δS, ∆S, and ∆S) from the Paleoproterozoic Seidorechka and Polisarka Sedimentary Formations on the Fennoscandian Shield, northwest Russia, that address this issue. Sulfides in the former preserve evidence of mass-independent fractionation of sulfur isotopes (S-MIF) falling within uncertainty of the Archean reference array with a ∆S/∆S slope of -1.

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Nitrate is common in Mars sediments owing to long-term atmospheric photolysis, oxidation, and potentially, impact shock heating. The Atacama Desert in Chile, which is the driest region on Earth and rich in nitrate deposits, is used as a Mars analog in this study to explore the potential effects of high nitrate levels on growth of extremophilic ecosystems. Seven study sites sampled across an aridity gradient in the Atacama Desert were categorized into 3 clusters-hyperarid, middle, and arid sites-as defined by essential soil physical and chemical properties.

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During an infectious disease modeling study, a rhesus macaque (), experienced acute transient tachypnea including transient severe motion during the 70-second phases of serial contrast-enhanced magnetic resonance imaging of the abdomen. This same animal experienced transient severe motion during all but 2 of the 8 scans of the year-long study. This animal was the only animal in the study (1 of 12) to have this reaction to gadoxetate; the animal also vomited after the contrast injection once on day 146 of the study.

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Rationale: Triple oxygen isotopes ( O/ O/ O) in nitrate are a valuable tool to ascertain the pathways of nitrate formation in the atmosphere and the fate of nitrate in ecosystems. Here we present a new method for determining Δ O values in nitrates, based on nitrate-water isotope equilibration (IE) and subsequent isotopic analysis of water using cavity ringdown laser spectroscopy (CRDS).

Methods: Nitrate oxygen (O-NO ) is equilibrated with water oxygen (O-H O) at low pH and 80°C.

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The potential habitability of an exoplanet is traditionally assessed by determining whether its orbit falls within the circumstellar "habitable zone" of its star, defined as the distance at which water could be liquid on the surface of a planet (Kopparapu et al., 2013 ). Traditionally, these limits are determined by radiative-convective climate models, which are used to predict surface temperatures at user-specified levels of greenhouse gases.

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Major changes in atmospheric and ocean chemistry occurred in the Paleoproterozoic era (2.5 to 1.6 billion years ago).

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Locations on Earth that provide insights into processes that may be occurring or may have occurred throughout martian history are often broadly deemed "Mars analog environments." As no single locale can precisely represent a past or present martian environment, it is important to focus on characterization of terrestrial processes that produce analogous features to those observed in specific regions of Mars or, if possible, specific time periods during martian history. Here, we report on the preservation of ionic species in soil samples collected from the Tindouf region of Morocco and compare them with the McMurdo Dry Valleys of Antarctica, the Atacama Desert in Chile, the martian meteorite EETA79001, and the in situ Mars analyses from the Phoenix Wet Chemistry Laboratory (WCL).

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Emerging evidence suggests that atmospheric oxygen may have varied before rising irreversibly ∼2.4 billion years ago, during the Great Oxidation Event (GOE). Significantly, however, pre-GOE atmospheric aberrations toward more reducing conditions-featuring a methane-derived organic-haze-have recently been suggested, yet their occurrence, causes, and significance remain underexplored.

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Article Synopsis
  • The rise of oxygen on Earth around 2.4 billion years ago sparked significant changes in marine nutrient cycles, particularly nitrogen, which affects global productivity.
  • Researchers used ancient South African rock records to analyze nitrogen isotopes and redox chemistry from around 2.31 billion years ago, filling a crucial gap in understanding nitrogen cycling during the Great Oxidation Event.
  • Findings indicate that with increased oxygen levels, a widespread aerobic nitrogen cycle emerged, facilitating the growth of nitrate-using organisms like cyanobacteria and eukaryotic phytoplankton, which likely played a role in marine biodiversity.
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Recognizing whether a planet can support life is a primary goal of future exoplanet spectral characterization missions, but past research on habitability assessment has largely ignored the vastly different conditions that have existed in our planet's long habitable history. This study presents simulations of a habitable yet dramatically different phase of Earth's history, when the atmosphere contained a Titan-like, organic-rich haze. Prior work has claimed a haze-rich Archean Earth (3.

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Background: Influenza results in up to 500,000 deaths annually. Seasonal influenza vaccines have an estimated 60% effectiveness, but provide little or no protection against novel subtypes, and may be less protective in high-risk groups. Neuraminidase inhibitors are recommended for the treatment of severe influenza infection, but are not proven to reduce mortality in severe disease.

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Background: Crohn's disease (CD) and ulcerative colitis (UC) challenge economies worldwide. Detailed health economic data of DRG based academic inpatient care for inflammatory bowel disease (IBD) patients in Europe is unavailable.

Methods: IBD was identified through ICD-10 K50 and K51 code groups.

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