Publications by authors named "Paul Bui"

Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon.

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A 62-year-old man was referred for a 68 Ga-prostate-specific membrane antigen (PSMA) PET/CT scan for newly diagnosed prostate cancer (ISUP grade 5), on the background of left vestibular schwannoma treated with surgical excision 25 years ago. PSMA PET study confirmed the presence of PSMA-avid malignancy in the left prostate lobe with no evidence of PSMA-avid nodal or distant metastasis. An incidental PSMA-avid focus (SUV max , 4.

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Background: Propofol use is contraindicated in patients on ketogenic diet (KD) due to higher risk of propofol infusion syndrome (PIS). This study is intended to provide a descriptive analysis of our experience with propofol bolus and short infusions for anesthetic care in patients on the KD and to evaluate if any signs of PIS were observed.

Methods: All patients on the KD who underwent anesthesia with propofol between 2012 and 2022 were reviewed.

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The hydroxyl radical (OH) fuels atmospheric chemical cycling as the main sink for methane and a driver of the formation and loss of many air pollutants, but direct OH observations are sparse. We develop and evaluate an observation-based proxy for short-term, spatial variations in OH (Proxy) in the remote marine troposphere using comprehensive measurements from the NASA Atmospheric Tomography (ATom) airborne campaign. Proxy is a reduced form of the OH steady-state equation representing the dominant OH production and loss pathways in the remote marine troposphere, according to box model simulations of OH constrained with ATom observations.

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Carbonaceous emissions from wildfires are a dynamic mixture of gases and particles that have important impacts on air quality and climate. Emissions that feed atmospheric models are estimated using burned area and fire radiative power (FRP) methods that rely on satellite products. These approaches show wide variability and have large uncertainties, and their accuracy is challenging to evaluate due to limited aircraft and ground measurements.

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A 74-year-old man was referred for a Ga-prostate-specific membrane antigen (PSMA) PET/CT scan for newly diagnosed prostate cancer which confirmed the presence of PSMA avid cancer in the right gland with no evidence of PSMA metastasis. Incidentally, there was a markedly PSMA avid (SUVmax 7.0) lobulated periventricular mass in the region of the left basal ganglia which was T2 hyperintense and T1 hypointense with perilesional oedema and vivid Gadolinium enhancement on MRI.

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Oceans emit large quantities of dimethyl sulfide (DMS) to the marine atmosphere. The oxidation of DMS leads to the formation and growth of cloud condensation nuclei (CCN) with consequent effects on Earth's radiation balance and climate. The quantitative assessment of the impact of DMS emissions on CCN concentrations necessitates a detailed description of the oxidation of DMS in the presence of existing aerosol particles and clouds.

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Natural aerosols in pristine regions form the baseline used to evaluate the impact of anthropogenic aerosols on climate. Sea spray aerosol (SSA) is a major component of natural aerosols. Despite its importance, the abundance of SSA is poorly constrained.

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Dimethyl sulfide (DMS), emitted from the oceans, is the most abundant biological source of sulfur to the marine atmosphere. Atmospheric DMS is oxidized to condensable products that form secondary aerosols that affect Earth's radiative balance by scattering solar radiation and serving as cloud condensation nuclei. We report the atmospheric discovery of a previously unquantified DMS oxidation product, hydroperoxymethyl thioformate (HPMTF, HOOCHSCHO), identified through global-scale airborne observations that demonstrate it to be a major reservoir of marine sulfur.

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The hydroxyl radical (OH) fuels tropospheric ozone production and governs the lifetime of methane and many other gases. Existing methods to quantify global OH are limited to annual and global-to-hemispheric averages. Finer resolution is essential for isolating model deficiencies and building process-level understanding.

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Optically thin cirrus near the tropical tropopause regulate the humidity of air entering the stratosphere, which in turn has a strong influence on the Earth's radiation budget and climate. Recent high-altitude, unmanned aircraft measurements provide evidence for two distinct classes of cirrus formed in the tropical tropopause region: (i) vertically extensive cirrus with low ice number concentrations, low extinctions, and large supersaturations (up to ∼70%) with respect to ice; and (ii) vertically thin cirrus layers with much higher ice concentrations that effectively deplete the vapor in excess of saturation. The persistent supersaturation in the former class of cirrus is consistent with the long time-scales (several hours or longer) for quenching of vapor in excess of saturation given the low ice concentrations and cold tropical tropopause temperatures.

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Aim: This study was designed to document the factors influencing therapeutic decisions in the management of diabetes in relation to stage of medical career.

Methods: An anonymous survey was distributed among medical students, resident medical officers (RMOs) and general practitioners (GPs) presenting a hypothetical case of a 58 year old patient with sub-optimally controlled diabetes on metfomin and gliclazide. Participants were then asked for their next step in management and about factors that would influence their decision-making.

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Airborne observations of ozone, temperature and the spectral actinic photon flux for ozone in the Arctic lower stratosphere April-September 1997 and January-March 2000 allow a connection to be made between the rate of production of translationally hot atoms and molecules via ozone photodissociation and the intermittency of temperature. Seen in the context of non-equilibrium statistical mechanics literature results from molecular dynamics simulations, the observed correlation between the molecular scale production of translationally hot atoms and molecules and the macroscopic fluid mechanical intermittency of temperature may imply a departure from Maxwell-Boltzmann distributions of molecular velocities, with consequences for chemistry, radiative line shapes and turbulence in the atmosphere, arising from overpopulated high velocity tails of the probability distribution functions (PDFs).

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