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In this study, a rapid and sensitive method using capillary electrophoresis with indirect UV detection and minimal sample pretreatment was developed and evaluated to analyze choline chloride in oilfield process water samples. To improve peak resolution and separation of choline chloride from other cations present in the samples, the addition of a cationic visualization agent in the background electrolyte, imidazole, and a complexing agent, 18-crown-6, were introduced. Other factors affecting separation and sensitivity were also investigated. Under optimized conditions, choline chloride was baseline separated (1.5 between adjacent peaks. The limits of detection (signal-to-noise ratio = 3) and quantitation (signal-to-noise ratio = 10) were 14.7 and 48.9 mg [L.sup.-1] respectively. The peak area and migration time's intraday and interday precision (percent RSD) were all Key words: choline chloride, oilfield process water, capillary electrophoresis, liquid chromatography--mass spectrometry, Reinecke salt gravimetry. Dans cette etude, nous avons mis au point une methode rapide et sensible faisant appel a l'electrophorese capillaire a detection UV indirecte et comportant un pretraitement minimal des echantillons, et nous l'avons evaluee dans le cadre de l'analyse du chlorure de choline dans des echantillons d'eaux de traitement provenant de champs petroliferes. En vue d'ameliorer la resolution des pics et la separation du chlorure de choline des autres cations presents dans les echantillons, nous avons ajoute a l'electrolyte support un agent de visualisation cationique, l'imidazole, et un agent complexant, l'ether 18-couronne-6. Nous avons egalement etudie d'autres facteurs influant sur la separation et la sensibilite. Dans les conditions optimisees, le chlorure de choline a ete separe a la ligne de base (1,5 entre les pics adjacents. Les limites de detection (rapport signal/bruit = 3) et de quantification (rapport signal/bruit = 10) etaient respectivement de 14,7 et de 48,9 mg*[L.sup.-1]. Les valeurs de precision intrajournaliere et interjournaliere (coefficient de variation [CV] en %) de l'aire sous la courbe et du temps de migration etaient toutes Mots-cles: chlorure de choline, eaux de traitement des champs petroliferes, electrophorese capillaire, chromatographie liquide couplee a la spectrometrie de masse, methode gravimetrique au sel de Reinecke., Introduction Large-scale hydraulic fracturing of oil and gas bearing formations as a method of well stimulation has increased substantially in recent years, especially for tight reservoirs such as those containing [...]

The article discusses a phylogenetic analysis on dengue virus (DENV) serotype 2 Cosmopolitan genotype in Ho Chi Minh, Vietnam. The study explored DENV lineages circulating in Ho Chi Minh City using samples from dengue patients in research studies at the Hospital for Tropical Diseases from 2017-2022 and it estimated ancestral node locations via root-to-tip regression analyses. It examined the dynamics of DENV prevalence, spread and transmission within Vietnam.

Objective: To examine urologic transfers and rate of tertiary center interventions from 4 geographically distinct academic medical centers.Methods: Four academic medical centers were selected for this study including Baylor College of Medicine, University of Alabama at Birmingham, University of Kentucky, and University of Pennsylvania Hospital (Penn). Baylor College of Medicine and Penn primarily service large metropolitan city centers and University of Kentucky and University of Alabama at Birmingham primarily service large rural populations. Transfer logs were pulled for each institution over a 2-year period, and a retrospective chart review was performed to evaluate transfer diagnosis and need for procedural management upon admission. Date of transfer, transfer diagnosis, and interventions performed during tertiary center admission were extracted from the transfer log data sets. The transfer diagnosis was categorized into 1 of 11 mutually exclusive categories.Results: Overall, 984 urologic transfers were included. Sixty-nine percent (682/984) of patients were transferred to the 2 rural centers, and 30.7% (302/984) were transferred to the 2 metropolitan centers. The most common reason for transfer was nephrolithiasis at 26% (256 of 984 transfers). The overall surgical intervention rate for all urologic transfers in this study was 44.4% (437 of 984 total transfers). Rural center transfers had a lower rate of surgical intervention than metropolitan centers (42.7% vs 48.3%) as well as a markedly higher number of total transfers during the study period (682 vs 302).Conclusion: Given that a majority of patients did not require surgical intervention, methods for avoiding unnecessary urologic transfers are warranted. [ABSTRACT FROM AUTHOR]

The Ovarian-Adnexal Reporting and Data System (O-RADS) MRI risk stratification system provides a standardized lexicon and evidence-based risk score for evaluation of adnexal lesions. The goals of the lexicon and risk score are to improve report quality and communication between radiologists and clinicians, reduce variability in the reporting language, and optimize management of adnexal lesions. The O-RADS MRI risk score is based on the presence or absence of specific imaging features, including the lipid content, enhancing solid tissue, number of loculi, and fluid type. The probability of malignancy ranges from less than 0.5% when there are benign features to approximately 90% when there is solid tissue with a high-risk time-intensity curve. This information can aid in optimizing management of patients with adnexal lesions. The authors present an algorithmic approach to the O-RADS MRI risk stratification system and highlight key teaching points and common pitfalls. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.