Publications by authors named "Timothy Brown"

Study Objectives: Melanopsin-expressing retinal ganglion cells, which provide light information to time sleep and entrain circadian clocks, also influence perceived brightness raising the possibility that psychophysical paradigms could be used to explore the origins and implications of variability in melanopic sensitivity. We aimed to develop accessible psychophysical tests of melanopic vision and relate outcomes with a pupillometric measure of melanopsin function (post-illumination pupil response; PIPR) and prior light exposure.

Methods: Individually calibrated pairs of isoluminant stimuli differing in melanopic radiance from a four primary source were presented sequentially with superimposed random colour offsets in a two alternative forced choice brightness preference paradigm to 41 naïve adult participants with personal light exposure data for the prior 7 days and PIPR measures defined by comparing maintained pupil constriction for luminance matched 'red' vs 'blue' pulses.

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There is limited information about accountable care organization (ACO) variation in equity of ambulatory care quality. We examine whether equity of care changed for racial and ethnic minority patients from 2019 to 2022 and the extent to which equity of care performance varied for 11 ACOs in Massachusetts over time. We analyzed ACO-level changes in equity of care for 8 ambulatory care quality measures for Asian, Black, and Hispanic patients, measured as the percentage point difference between each group and the majority non-Hispanic White patient group.

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Climate change has emerged as a key threat to biodiversity, leading to broad-scale shifts in distributions of marine and terrestrial species as they attempt to track thermally suitable habitat. By contrast, our understanding of climate responses of freshwater species is relatively undeveloped, limiting our knowledge of whether projected warming will lead to freshwater biodiversity loss. Here, we linked a multicontinental database of riverine fish population abundance time series collected from 1958 to 2019 to temperature data from the same period.

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We describe the impact of screening on outcomes of patients diagnosed with hepatocellular carcinoma (HCC) in an urban safety-net healthcare system compared to a non-screened cohort diagnosed with HCC. Patients diagnosed with HCC at John Peter Smith Health Network were identified by querying the hospital tumor registry and allocated to the screened cohort if they had undergone any liver imaging within one year prior to HCC diagnosis, while the remainder were allocated to the non-screened cohort. Kaplan-Meier methods and log-rank tests were used to compare 3-year survival curves from an index date of HCC diagnosis.

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Article Synopsis
  • Light plays a crucial role in regulating the physiology and behavior of mammals, and improper light exposure can lead to health issues due to disrupted circadian rhythms.
  • The study introduces a new method for measuring light using a photoreceptor-specific (α-opic) approach that accounts for variations across different mammalian species and their unique photoreceptor types.
  • Results show that α-opic measurements provide better predictions of physiological responses to light than the traditional lux measurements, potentially enhancing animal welfare, scientific research, agriculture, and energy efficiency.
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Unlabelled: Policy Points What are the facilitators and barriers of physician group participation in a performance-based financial incentive program aimed at improving equity of care by patient race and ethnicity? Launching financial incentives to improve racial equity has required extensive organizational change management for participating physician groups, including major investments to improve quality management systems. Carefully designing financial incentives to encourage equity improvement while managing unintended consequences, and considering physician groups' populations served, baseline maturity of quality management systems, and efforts to assess and address patients' social risk factors have been central to prepare physician groups for financial incentives to improve equity of care. Given the major investments required of physician groups to prepare for financial incentives that reward equity improvement, alignment of equity of care measure specifications and reporting requirements across payers could facilitate physician group engagement.

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Hematopoietic stem cells (HSCs) are supported by the bone marrow microenvironment to maintain normal production of blood cells. The niche may be considered an "ecosystem" that support the function of HSCs and other supportive cells. Alterations in the bone marrow niche are commonly observed in hematologic malignancies.

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Objectives: We identify the association between high- and low-intensity case management services on hospital and emergency department (ED) use among CommunityConnect patients.

Background: Social needs case management services vary in intensity, including the modality, workforce specialization, and maximum caseload. CommunityConnect is a social needs case management program implemented by Contra Costa Health, a county safety-net health system in California's San Francisco Bay Area.

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Objective: The objectives of this study were 1) to identify the effects cannabis has on driving performance and individual motor practices when on the freeway compared to placebo and 2) to bring context to the effects of cannabis on driving by comparing effect sizes to those of alcohol.

Methods: Data for analysis was collected from a study of fifty-three participants with a history of tetrahydrocannabinol (THC) cannabis use who completed three visits in randomized order (placebo (0% THC), 6.18% THC, and 10.

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Background: Colon cancers are categorized into mismatch repair deficient/microsatellite unstable (MSI-H) and mismatch repair proficient/microsatellite stable (MSS) cancers. This study aims to compare the disease characteristics and trends in the utilization of cancer therapies across different age groups and stages in these two groups.

Methods: MSI-H and MSS colon adenocarcinomas from 2010 to 2016 were identified using the National Cancer Database.

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Any electrical signal propagating in a metallic conductor loses amplitude due to the natural resistance of the metal. Compensating for such losses presently requires repeatedly breaking the conductor and interposing amplifiers that consume and regenerate the signal. This century-old primitive severely constrains the design and performance of modern interconnect-dense chips.

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There is growing interest in material candidates with properties that can be engineered beyond traditional design limits. Compositionally complex oxides (CCO), often called high entropy oxides, are excellent candidates, wherein a lattice site shares more than four cations, forming single-phase solid solutions with unique properties. However, the nature of compositional complexity in dictating properties remains unclear, with characteristics that are difficult to calculate from first principles.

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Purpose: Systemic therapy with atezolizumab and bevacizumab can extend life for patients with advanced hepatocellular carcinoma (HCC). However, there is substantial variability in response to therapy and overall survival. Although current prognostic models have been validated in HCC, they primarily consider covariates that may be reflective of the severity of the underlying liver disease of patients with HCC.

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Introduction: Despite several therapeutic advancements, the proportion of patients with advanced biliary tract cancers (BTC) surviving 5 years from diagnosis remains dismal. The increasing recognition of targetable genetic alterations in BTCs has ushered in a new era in the treatment of these patients. Newer therapeutic agents targeting mutations such as isocitrate dehydrogenase (IDH), fibroblastic growth factor receptor (FGFR), human epidermal growth factor receptor (HER), and so on have established a new standard of care for treatment upon progression on frontline therapy in patients with disease harboring these mutations.

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This national US study determined the causal impact of shared decision making (SDM) on pain outcomes, including any overall pain and the subcategories of any acute pain and any chronic pain. We additionally examined whether the causal impact of SDM on overall pain is moderated by gender, race-ethnicity, clinician-patient racial-ethnic concordance, and clinician-patient gender concordance. We used national US data from the 2003-2017 Medical Expenditure Panel Survey, which were externally valid to the US national non-institutionalized population, employed a standard measure of shared decision making, and applied an internally-valid two-stage least squares approach that used the peer SDM behavior of similar clinicians as an instrument.

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Heat dissipation is a natural consequence of operating any electronic system. In nearly all computing systems, such heat is usually minimized by design and cooling. Here, we show that the temporal dynamics of internally produced heat in electronic devices can be engineered to both encode information within a single device and process information across multiple devices.

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Neuroimaging is a popular method to map brain structural and functional patterns to complex human traits. Recently published observations cast doubt upon these prospects, particularly for prediction of cognitive traits from structural and resting state functional magnetic resonance imaging (MRI). We leverage baseline data from thousands of children in the Adolescent Brain Cognitive DevelopmentSM Study to inform the replication sample size required with univariate and multivariate methods across different imaging modalities to detect reproducible brain-behavior associations.

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While digital computers rely on software-generated pseudo-random number generators, hardware-based true random number generators (TRNGs), which employ the natural physics of the underlying hardware, provide true stochasticity, and power and area efficiency. Research into TRNGs has extensively relied on the unpredictability in phase transitions, but such phase transitions are difficult to control given their often abrupt and narrow parameter ranges (e.g.

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Spontaneously blinking fluorophores permit the detection and localization of individual molecules without reducing buffers or caging groups, thus simplifying single-molecule localization microscopy (SMLM). The intrinsic blinking properties of such dyes are dictated by molecular structure and modulated by environment, which can limit utility. We report a series of tuned spontaneously blinking dyes with duty cycles that span two orders of magnitude, allowing facile SMLM in cells and dense biomolecular structures.

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Single-molecule localization microscopy (SMLM) uses activatable or switchable fluorophores to create non-diffraction limited maps of molecular location in biological samples. Despite the utility of this imaging technique, the portfolio of appropriate labels for SMLM remains limited. Here, we describe a general strategy for the construction of "glitter bomb" labels by simply combining rhodamine and coumarin dyes though an amide bond.

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Light exposure is a vital regulator of physiology and behavior in humans. However, monitoring of light exposure is not included in current wearable Internet of Things (IoT) devices, and only recently have international standards defined [Formula: see text] -optic equivalent daylight illuminance (EDI) measures for how the eye responds to light. This article reports a wearable light sensor node that can be incorporated into the IoT to provide monitoring of EDI exposure in real-world settings.

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We developed a significantly improved genetically encoded quantitative adenosine triphosphate (ATP) sensor to provide real-time dynamics of ATP levels in subcellular compartments. iATPSnFR2 is a variant of iATPSnFR1, a previously developed sensor that has circularly permuted superfolder green fluorescent protein (GFP) inserted between the ATP-binding helices of the -subunit of a bacterial F-F ATPase. Optimizing the linkers joining the two domains resulted in a ~fivefold to sixfold improvement in the dynamic range compared to the previous-generation sensor, with excellent discrimination against other analytes, and affinity variants varying from 4 µM to 500 µM.

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Article Synopsis
  • Research is crucial for residency and fellowship programs, and an annual research project can enhance productivity, as explored through a review of presentations from a symposium over five years.
  • Out of 98 presentations analyzed, the overall publication rate was 54%, with residents having a higher first-author publication percentage (70%) compared to fellows (54%).
  • Feedback from current residents indicated a strong perceived value of the annual research symposium, supporting its importance in fostering academic development.
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