Publications by authors named "Simpson W"

Outdoor air pollution is a significant problem worldwide. Policies developed to mitigate air pollution require support from local residents to be successful. While some research has examined various social and psychological metrics associated with support for some types of pollution mitigation, less is known about what variables are critical in resident support for different types of policies that help mitigate air pollution associated with woodsmoke.

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The prevailing view for aqueous secondary aerosol formation is that it occurs in clouds and fogs, owing to the large liquid water content compared to minute levels in fine particles. Our research indicates that this view may need reevaluation due to enhancements in aqueous reactions in highly concentrated small particles. Here, we show that low temperature can play a role through a unique effect on particle pH that can substantially modulate secondary aerosol formation.

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Within and surrounding high-latitude cities, poor air quality disturbs Arctic ecosystems, influences the climate, and harms human health. The Fairbanks North Star Borough has wintertime particulate matter (PM) concentrations that exceed the Environmental Protection Agency's (EPA) threshold for public health. Particulate sulfate (SO ) is the most abundant inorganic species and contributes approximately 20% of the total PM mass in Fairbanks, but air quality models underestimate observed sulfate concentrations.

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Article Synopsis
  • EPFRs are significant pollutants linked to air quality issues, especially in Fairbanks, Alaska, where they were studied during winter 2022.
  • High concentrations of EPFRs were found during temperature inversions and were associated with markers of incomplete combustion, including carbon monoxide and elemental carbon.
  • Exposure to EPFR levels can be comparable to smoking 0.4-1 cigarette daily, and they may induce oxidative stress in the respiratory system based on their strong correlation with hydroxyl radical formation.
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Background: Digital speech assessment has potential relevance in the earliest, preclinical stages of Alzheimer's disease (AD). We evaluated the feasibility, test-retest reliability, and association with AD-related amyloid-beta (Aβ) pathology of speech acoustics measured over multiple assessments in a remote setting.

Methods: Fifty cognitively unimpaired adults (Age 68 ± 6.

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Hydroxymethanesulfonate (HMS) in fine aerosol particles has been reported at significant concentrations along with sulfate under extreme cold conditions (-35 °C) in Fairbanks, Alaska, a high latitude city. HMS, a component of S(IV) and an adduct of formaldehyde and sulfur dioxide, forms in liquid water. Previous studies may have overestimated HMS concentrations by grouping it with other S(IV) species.

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The inoculation of endophytes into modern cereals, resulting in systemic infection, depends on the genetics of both the host and the endophyte strain deployed. Until very recently, the only modern cereal to have been infected with , in which normal phenotype seed-transmitted associations were achieved, is rye (). Whilst minor in-roads have been achieved in infecting hexaploid wheat (), the phenotypes of these associations have all been extremely poor, including host death and stunting.

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Many microbial genes involved in degrading recalcitrant environmental contaminants such as polycyclic aromatic hydrocarbons (PAHs) have been identified and characterized. However, all molecular mechanisms required for PAH utilization have not yet been elucidated. In this work, we demonstrate the proposed involvement of lasso peptides in the utilization of the PAH phenanthrene in Sphingomonas BPH.

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The space of Retzius is an important anatomic location for pathology. Pathology in the space of Retzius is more common than previously believed, especially as more cases are discovered with increased use of cross-sectional imaging. Knowledge of the anatomy of the Space of Retzius is crucial for identifying and distinguishing between benign and pathological findings.

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The Alaskan Layered Pollution And Chemical Analysis (ALPACA) field experiment was a collaborative study designed to improve understanding of pollution sources and chemical processes during winter (cold climate and low-photochemical activity), to investigate indoor pollution, and to study dispersion of pollution as affected by frequent temperature inversions. A number of the research goals were motivated by questions raised by residents of Fairbanks, Alaska, where the study was held. This paper describes the measurement strategies and the conditions encountered during the January and February 2022 field experiment, and reports early examples of how the measurements addressed research goals, particularly those of interest to the residents.

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The indoor air quality of a residential home during winter in Fairbanks, Alaska, was investigated and contrasted with outdoor levels. Twenty-four-hour average indoor and outdoor filter samples were collected from January 17 to February 25, 2022, in a residential area with high outdoor PM concentrations. The oxidative potential of PM was determined using the dithiothreitol-depletion assay (OP).

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The oxidative potential (OP) of outdoor PM in wintertime Fairbanks, Alaska, is investigated and compared to those in wintertime Atlanta and Los Angeles. Approximately 40 filter samples collected in January-February 2022 at a Fairbanks residential site were analyzed for OP utilizing dithiothreitol-depletion (OP) and hydroxyl-generation (OP) assays. The study-average PM mass concentration was 12.

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Purpose: To evaluate the response to nifedipine administration measured by changes in hepatic arterial (HA) flow on post-operative Doppler ultrasound (US) to predict short-term complications and long-term outcomes in liver transplant (LT) patients.

Methods: Patients who underwent LT with post-operative Doppler US within 3 days between 1 January 2005 and 31 December 2015 were included in this retrospective single center study. The patients who received and did not receive nifedipine during the Doppler US comprised the study and control groups, respectively.

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Background: Changes to speech and language are common symptoms across different subtypes of frontotemporal dementia (FTD). These changes affect the ability to communicate, impacting everyday functions. Accurately assessing these changes may help clinicians to track disease progression and detect response to treatment.

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spp. often form mutualistic interactions with cool-season grasses, such as . However, the molecular mechanisms underlying this interaction remain poorly understood.

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Objective: Depression is a common mental health disorder and a major public health concern, significantly interfering with the lives of those affected. The complex clinical presentation of depression complicates symptom assessments. Day-to-day fluctuations of depression symptoms within an individual bring an additional barrier, since infrequent testing may not reveal symptom fluctuation.

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Unlabelled: Speech and language changes occur in Alzheimer's disease (AD), but few studies have characterized their longitudinal course. We analyzed open-ended speech samples from a prodromal-to-mild AD cohort to develop a novel composite score to characterize progressive speech changes. Participant speech from the Clinical Dementia Rating (CDR) interview was analyzed to compute metrics reflecting speech and language characteristics.

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Aphids are major pests of cereal and pasture grasses throughout the world, vectoring disease and reducing plant production. There are few control options other than insecticides. endophytes that produce loline alkaloids in their hosts provide a possible mechanism of control, with both meadow fescue and tall fescue naturally infected with loline-producing endophytes showing a resistance to We screened spp.

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is widely utilized due to its pharmaceutical value. Mycelial protein forms a key active component of and determines the medicinal potential of fungus. Here, we describe the development of an optimized fermentation medium to obtain more mycelial soluble protein from using response surface methodology (RSM) and investigate the increased mycelial protein content using transcriptomics.

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The H-02 constructed wetland was designed to remove metals (primarily copper and zinc) to treat building process water and storm water runoff from multiple sources associated with the Tritium Facility at the DOE-Savannah River Site, Aiken, SC. The concentration of Cu and Zn in the sediments has increased over the lifetime of the wetland and is a concern. A bioremediation option was investigated at the laboratory scale utilizing a newly isolated bacterium of the copper metabolizing genus Cupriavidus isolated from Tim's Branch Creek, a second-order stream that eventually serves as a tributary to the Savannah River, contaminated with uranium and other metals including copper, nickel, and mercury.

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Background: Radiation lobectomy (RL) utilizes Yttrium-90 (Y90) radioembolization for achieving tumor control and inducing contralateral lobe hypertrophy. Our objective was to evaluate the chronological changes occurring radiologically and histopathologically after Y90 RL.

Methods: We retrospectively reviewed 22 patients with chronic liver disease who underwent Y90 RL prior to planned liver resection for hepatocellular carcinoma.

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