Bioassay monitoring is an important capability for any facility that works with significant amounts of radioactive material. The speed at which these analyses can be made is critical in the event of ...a potential exposure. In this study, we present a new method that facilitates the rapid separation of uranium from a urine matrix for assay and isotopic determination by inductively coupled plasma mass spectrometry. This method is validated with archived urine samples that were previously analyzed using established, more time consuming methods. The sources of uncertainty for uranium assay and isotopic measurements are modelled using the Monte Carlo method to better understand the precision and accuracy of this method at the limit of quantification.
The phyllosphere epiphytic microbiome is composed of microorganisms that colonize the external aerial portions of plants. Relationships of plant responses to specific microorganisms–both pathogenic ...and beneficial–have been examined, but the phyllosphere microbiome functional and metabolic profile responses are not well described. Changing crop growth conditions, such as increased drought, can have profound impacts on crop productivity. Also, epiphytic microbial communities provide a new target for crop yield optimization. We compared Zea mays leaf microbiomes collected under drought and well-watered conditions by examining functional gene annotation patterns across three physically disparate locations each with and without drought treatment, through the application of short read metagenomic sequencing. Drought samples exhibited different functional sequence compositions at each of the three field sites. Maize phyllosphere functional profiles revealed a wide variety of metabolic and regulatory processes that differed in drought and normal water conditions and provide key baseline information for future selective breeding.
Ambient particulate matter (PM) air pollution exposure has been associated with increases in QT interval duration (QT). However, innate susceptibility to PM-associated QT prolongation has not been ...characterized.
To characterize genetic susceptibility to PM-associated QT prolongation in a multi-racial/ethnic, genome-wide association study (GWAS).
Using repeated electrocardiograms (1986–2004), longitudinal data on PM<10 μm in diameter (PM
), and generalized estimating equations methods adapted for low-prevalence exposure, we estimated approximately 2.5×10
SNP×PM
interactions among nine Women’s Health Initiative clinical trials and Atherosclerosis Risk in Communities Study subpopulations (n=22,158), then combined subpopulation-specific results in a fixed-effects, inverse variance-weighted meta-analysis.
A common variant (rs1619661; coded allele:
) significantly modified the QT-PM
association (p=2.11×10
). At PM
concentrations >90th percentile, QT increased 7 ms across the CC and TT genotypes: 397 (95% confidence interval: 396, 399) to 404 (403, 404) ms. However, QT changed minimally across rs1619661 genotypes at lower PM
concentrations. The rs1619661 variant is on chromosome 10, 132 kilobase (kb) downstream from CXCL12, which encodes a chemokine, stromal cell-derived factor 1, that is expressed in cardiomyocytes and decreases calcium influx across the L-type Ca
channel.
The findings suggest that biologically plausible genetic factors may alter susceptibility to PM
-associated QT prolongation in populations protected by the U.S. Environmental Protection Agency’s National Ambient Air Quality Standards. Independent replication and functional characterization are necessary to validate our findings. https://doi.org/10.1289/EHP347
Sphenoid opacifications may be discovered during the radiological work up of patients presenting with fever, headache, or neurological changes. While most of these patients do not require surgical ...intervention, prompt assessment and management is nevertheless required. Ten patients who underwent sphenoidotomy for drainage or biopsy at Montefiore Hospital during a 4-year period from September 1995 through January 2000 are presented. Nine out of 10 patients had predisposing factors such as AIDS, diabetes, leukemia, and end-stage renal disease. The most common presentation was altered mental status. One patient rapidly developed cavernous sinus thrombosis. Microbiology of sphenoid cultures included various fungi, Mycobacterium avium intracellulare, coagulase negative Staphylococci, and Corynebacterium. Neoplastic processes included non-Hodgkin's lymphoma and sinonasal undifferentiated carcinoma. When evaluating hospitalized patients with sphenoid sinus disease, a thorough history and a bedside nasal endoscopy should be performed. Conservative management in the form of intravenous antibiotics and topical decongestion should always be the first line of treatment. Those patients with clinical or radiological evidence of disease extending beyond the confines of the sphenoid sinus require immediate surgical intervention.
The genetic basis of supraventricular and ventricular ectopy (SVE, VE) remains largely uncharacterized, despite established genetic mechanisms of arrhythmogenesis. To identify novel genetic variants ...associated with SVE/VE in ancestrally diverse human populations, we conducted a genome-wide association study of electrocardiographically identified SVE and VE in five cohorts including approximately 43,000 participants of African, European and Hispanic/Latino ancestry. In thirteen ancestry-stratified subgroups, we tested multivariable-adjusted associations of SVE and VE with single nucleotide polymorphism (SNP) dosage. We combined subgroup-specific association estimates in inverse variance-weighted, fixed-effects and Bayesian meta-analyses. We also combined fixed-effects meta-analytic t-test statistics for SVE and VE in multi-trait SNP association analyses. No loci reached genome-wide significance in trans-ethnic meta-analyses. However, we found genome-wide significant SNPs intronic to an apoptosis-enhancing gene previously associated with QRS interval duration (FAF1; lead SNP rs7545860; effect allele frequency = 0.02; P = 2.0 × 10
) in multi-trait analysis among European ancestry participants and near a locus encoding calcium-dependent glycoproteins (DSC3; lead SNP rs8086068; effect allele frequency = 0.17) in meta-analysis of SVE (P = 4.0 × 10
) and multi-trait analysis (P = 2.9 × 10
) among African ancestry participants. The novel findings suggest several mechanisms by which genetic variation may predispose to ectopy in humans and highlight the potential value of leveraging pleiotropy in future studies of ectopy-related phenotypes.
We introduce AdCraft, a novel benchmark environment for the Reinforcement Learning (RL) community distinguished by its stochastic and non-stationary properties. The environment simulates bidding and ...budgeting dynamics within Search Engine Marketing (SEM), a digital marketing technique utilizing paid advertising to enhance the visibility of websites on search engine results pages (SERPs). The performance of SEM advertisement campaigns depends on several factors, including keyword selection, ad design, bid management, budget adjustments, and performance monitoring. Deep RL recently emerged as a potential strategy to optimize campaign profitability within the complex and dynamic landscape of SEM, but it requires substantial data, which may be costly or infeasible to acquire in practice. Our customizable environment enables practitioners to assess and enhance the robustness of RL algorithms pertinent to SEM bid and budget management without such costs. Through a series of experiments within the environment, we demonstrate the challenges imposed on agent convergence and performance by sparsity and non-stationarity. We hope these challenges further encourage discourse and development around effective strategies for managing real-world uncertainties.
Generalizations to the permutation test are introduced to allow for situations in which the null model is not exchangeable. It is shown that the generalized permutation tests are exact, and a partial ...converse: that any test function that is exact on all probability densities coincides with a generalized permutation test on a particular region, is established. A most powerful generalized permutation test is derived in closed form. Approximations to the most powerful generalized permutation test are proposed to reduce the computational burden required to compute the complete test. In particular, an explicit form for the approximate test is derived in terms of a multinomial Bernstein polynomial approximation, and its convergence to the most powerful generalized permutation test is demonstrated. In the case where the determination of p-values is of greater interest than testing of hypotheses, two approaches to estimation of significance are analyzed. Bounds on the deviation from significance of the exact most powerful test are given in terms of sample size. For both estimators, as sample size approaches infinity, the estimator converges to the significance of the most powerful generalized permutation test under mild conditions. Applications of generalized permutation testing to linear mixed models are provided.
To determine the usefulness of intraoperative frozen section (FS) examinations in establishing the diagnosis of thyroid cancer in patients undergoing thyroidectomy for nodules with indeterminate ...cytological features and to determine the cost-effectiveness of FS examinations in this situation.
Retrospective medical record review. The results of fine-needle aspiration biopsies (FNABs), FS examinations, and final pathologic examinations are compared. A cost-effectiveness analysis of routine FS examinations compared with the cost of additional surgical procedures is performed.
A private surgical practice in a medical school-affiliated teaching hospital.
The records of all 480 patients undergoing thyroidectomy between January 1, 1998, and September 30, 2000, were reviewed. All 199 patients with a dominant thyroid nodule and FNAB results either highly suggestive of papillary cancer or indeterminate were studied.
Of the patients with FNAB results highly suggestive of papillary cancer, 95% had cancer according to the final pathologic examination results. The diagnosis of cancer was made by FS examination results in 67% of these patients. Of the remaining 178 patients whose FNAB result was indeterminate, 64 (36%) had thyroid cancer. Malignancy was diagnosed by FS examination results in 30 (47%) of these patients. If FS examinations had not been performed, these 30 patients would have required a second operation to complete a total thyroidectomy. The cost savings of routine FS examinations in patients with indeterminate FNAB results is 1298 US dollars per patient.
The routine performance of FS examinations in patients with thyroid nodules with indeterminate cytological features is a cost-effective way of avoiding a second surgical procedure if a total thyroidectomy is indicated. In patients with FNAB results highly suggestive of papillary cancer, FS examinations are not useful. In these patients, the definitive operation can be based on the results of the FNAB.
PDF
