Publications by authors named "TD Johnson"

Article Synopsis
  • Researchers analyze neuroimaging data by fitting general linear models to each pixel, often using spatial smoothing to induce regularization, but this can lead to inaccurate inference.
  • The authors propose a Bayesian spatial regression model that employs Gaussian process priors for better regularization of spatial effects, allowing for more powerful analyses.
  • The model incorporates a computationally efficient approximation to handle large data sets, and its effectiveness is demonstrated through an analysis of functional MRI data from children in a large study.
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The auditory steady state response (ASSR) arises when periodic sounds evoke stable responses in auditory networks that reflect the acoustic characteristics of the stimuli, such as the amplitude of the sound envelope. Larger for some stimulus rates than others, the ASSR in the human electroencephalogram (EEG) is notably maximal for sounds modulated in amplitude at 40 Hz. To investigate the local circuit underpinnings of the large ASSR to 40 Hz amplitude-modulated (AM) sounds, we acquired skull EEG and local field potential (LFP) recordings from primary auditory cortex (A1) in the rat during the presentation of 20, 30, 40, 50, and 80 Hz AM tones.

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Prepubertal obesity is growing at an alarming rate and is now considered a risk factor for renal injury. Recently, we reported that the early development of renal injury in obese Dahl salt-sensitive (SS) leptin receptor mutant (SS LepR mutant) rats was associated with increased T-cell infiltration and activation before puberty. Therefore, the current study investigated the effect of inhibiting T-cell activation with abatacept on the progression of renal injury in young obese SS LepR mutant rats before puberty.

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Purpose: Neoadjuvant chemotherapy is often administered for high-grade serous ovarian carcinoma (HGSC) prior to cytoreductive surgery. We evaluated treatment response by CT (simplified peritoneal carcinomatosis index [S-PCI]), pathology (chemotherapy response score [CRS]), laboratory markers (serum CA-125), and surgical outcomes, to identify predictors of disease-free survival.

Methods: For this retrospective, HIPAA-compliant, IRB-approved study, we identified 396 women with HGSC receiving neoadjuvant chemotherapy between 2010 and 2019.

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Article Synopsis
  • The study examines how redox conditions in groundwater influence the movement of nutrients and contaminants, which can impact human health, highlighting the importance of understanding these conditions across large areas like the contiguous United States.* -
  • Using a machine learning technique called random forest classification, researchers predicted groundwater redox conditions by analyzing data from over 30,000 wells and identified significant factors like geology, soil properties, and hydrologic position that affect oxic (oxygen-rich) conditions.* -
  • The findings indicate that the likelihood of having oxic groundwater is closely related to factors like stream proximity, depth from the water table, base flow index, and topographic wetness index, suggesting how water movement and soil characteristics play a role in oxygen levels in
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Background: Public health scholarship has uncovered a wide range of strategies used by industry actors to promote their products and influence government regulation. Less is known about the strategies used by non-government organisations to attempt to influence commercial practices. This narrative review applies a political science typology to identify a suite of 'inside' and 'outside' strategies used by NGOs to attempt to influence the commercial determinants of health.

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Background And Aims: A key histopathological feature of inflammatory bowel disease is damage to the mucosa, including breakdown of the epithelial barrier. Human enteroids and colonoids are a critical bench-to-bedside tool for studying the epithelium in inflammatory bowel disease. The goal of the current study was to define transcriptional differences in healthy versus diseased subjects that are sustained in enteroids and colonoids, including from disease-spared tissue.

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Purpose: To assess the influence of time of day when a study is interpreted on discrepancy rates for common and advanced studies performed in the acute community setting.

Methods: This retrospective study used the databank of a U.S.

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Prepubertal obesity is currently an epidemic and is considered as a major risk factor for renal injury. Previous studies have demonstrated that insulin resistance contributes to renal injury in obesity, independent of diabetes. However, studies examining the relationship between insulin resistance and renal injury in obese children are lacking.

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Purpose: Previous investigations into the causes of error by radiologists have addressed work schedule, volume, shift length, and sub-specialization. Studies regarding possible associations between radiologist errors and radiologist age and timing of residency training are lacking in the literature, to our knowledge. The aim of our study was to determine if radiologist age and residency graduation date is associated with diagnostic errors.

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Background: Gaze perception is a basic building block of social cognition, which is impaired in schizophrenia (SZ) and contributes to functional outcomes. Few studies, however, have investigated neural underpinnings of gaze perception and their relation to social cognition. We address this gap.

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Background: To investigate the complications that occurred in neonates born to mothers with coronavirus disease 2019 (COVID-19), focusing on neurological and neuroradiological findings, and to compare differences associated with the presence of maternal symptoms.

Methods: Ninety neonates from 88 mothers diagnosed with coronavirus disease 2019 (COVID-19) during pregnancy were retrospectively reviewed. Neonates were divided into two groups: symptomatic (Sym-M-N, n = 34) and asymptomatic mothers (Asym-M-N, n = 56).

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The hippocampus contains rich oscillatory activity, with continuous ebbs and flows of rhythmic currents that constrain its ability to integrate inputs. During associative learning, the hippocampus must integrate inputs from a range of sources carrying information about events and the contexts in which they occur. Under these circumstances, temporal coordination of activity between sender and receiver is likely essential for successful communication.

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Neuroradiologists and neurosurgeons increasingly opt to use functional magnetic resonance imaging (fMRI) to map functionally relevant brain regions for noninvasive presurgical planning and intraoperative neuronavigation. This application requires a high degree of spatial accuracy, but the fMRI signal-to-noise ratio (SNR) decreases as spatial resolution increases. In practice, fMRI scans can be collected at multiple spatial resolutions, and it is of interest to make more accurate inference on brain activity by combining data with different resolutions.

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Injectable biomaterials have been developed as potential minimally invasive therapies for treating myocardial infarction (MI) and heart failure. Christman et al. first showed that the injection of a biomaterial alone into rat myocardium can improve cardiac function after MI.

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Although gender has been identified as an important antecedent in workplace mistreatment research, empirical research has shown mixed results. Drawing on role congruity theory, we propose an interactive effect of gender and bottom-line mentality on being the target of mistreatment. Across two field studies, our results showed that whereas women experienced more mistreatment when they had higher levels of bottom-line mentality, men experienced more mistreatment when they had lower levels of bottom-line mentality.

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Background: A growing body of evidence has revealed the potential utility of 5-aminolevulinic acid (5-ALA) as a surgical adjunct in selected lower-grade gliomas. However, a reliable means of identifying which lower-grade gliomas will fluoresce has not been established.

Objective: To identify clinical and radiological factors predictive of intraoperative fluorescence in intermediate-grade gliomas.

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In 2019, 254 samples were collected from five aquifer systems to evaluate perfluoroalkyl and polyfluoroalkyl substance (PFAS) occurrence in groundwater used as a source of drinking water in the eastern United States. The samples were analyzed for 24 PFAS, major ions, nutrients, trace elements, dissolved organic carbon (DOC), volatile organic compounds (VOCs), pharmaceuticals, and tritium. Fourteen of the 24 PFAS were detected in groundwater, with 60 and 20% of public-supply and domestic wells, respectively, containing at least one PFAS detection.

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Over the past 2 decades Bayesian methods have been gaining popularity in many scientific disciplines. However, to this date, they are rarely part of formal graduate statistical training in clinical science. Although Bayesian methods can be an attractive alternative to classical methods for answering certain research questions, they involve a heavy "overhead" (e.

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In community settings, radiologists commonly function as multispecialty radiologists, interpreting examinations outside of their area of fellowship training. The purpose of this article was to compare discrepancy rates for preliminary interpretations of acute community-setting examinations that are concordant versus discordant with interpreting radiologists' area of fellowship training. This retrospective study used the databank of a U.

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Most Americans receive their drinking water from publicly supplied sources, a large portion of it from groundwater. Mapping these populations consistently and at a high resolution is important for understanding where the resource is used and needs to be protected. The results show that 269 million people are supplied by public supply, 107 million are supplied by groundwater and 162 million are supplied by surface water.

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Bipolar disorder (BD) is associated with a range of social cognitive deficits. This study investigated the functioning of the mentalizing brain system in BD probed by an eye gaze perception task during fMRI. Compared with healthy controls (n = 21), BD participants (n = 14) showed reduced preferential activation for self-directed gaze discrimination in the medial prefrontal cortex (mPFC) and temporo-parietal junction (TPJ), which was associated with poorer cognition/social cognition.

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We prospectively investigated the performance of the prostate-specific membrane antigen (PSMA) ligand Ga-PSMA-11 for detecting prostate adenocarcinoma in patients with elevated levels of prostate-specific antigen (PSA) after initial therapy. Ga-PSMA-11 hybrid PET was performed on 2,005 patients at the time of biochemically recurrent prostate cancer after radical prostatectomy (RP) (50.8%), definitive radiation therapy (RT) (19.

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