Automorphism Group of k((t))k((t)): Applications to the Bosonic String

This paper is concerned with the formulation of a non-pertubative theory of the bosonic string. We introduce a formal group $G$ which we propose as the ``universal moduli space'' for such a formulation. This is motivated because $G$ establishes a natural link between representations of the Virasoro algebra and the moduli space of curves. Among other properties of $G$ it is shown that a ``local'' version of the Mumford formula holds on $G$.Comment: 29 page

Evaluation of Natural Language Processing for the Identification of Crohn Disease-Related Variables in Spanish Electronic Health Records:A Validation Study for the PREMONITION-CD Project

Background: The exploration of clinically relevant information in the free text of electronic health records (EHRs) holds the potential to positively impact clinical practice as well as knowledge regarding Crohn disease (CD), an inflammatory bowel disease that may affect any segment of the gastrointestinal tract. The EHRead technology, a clinical natural language processing (cNLP) system, was designed to detect and extract clinical information from narratives in the clinical notes contained in EHRs. Objective: The aim of this study is to validate the performance of the EHRead technology in identifying information of patients with CD. Methods: We used the EHRead technology to explore and extract CD-related clinical information from EHRs. To validate this tool, we compared the output of the EHRead technology with a manually curated gold standard to assess the quality of our cNLP system in detecting records containing any reference to CD and its related variables. Results: The validation metrics for the main variable (CD) were a precision of 0.88, a recall of 0.98, and an F1 score of 0.93. Regarding the secondary variables, we obtained a precision of 0.91, a recall of 0.71, and an F1 score of 0.80 for CD flare, while for the variable vedolizumab (treatment), a precision, recall, and F1 score of 0.86, 0.94, and 0.90 were obtained, respectively. Conclusions: This evaluation demonstrates the ability of the EHRead technology to identify patients with CD and their related variables from the free text of EHRs. To the best of our knowledge, this study is the first to use a cNLP system for the identification of CD in EHRs written in Spanish. © 2022 JMIR Medical Informatics. All rights reserved

Esophageal Granular Cell Tumor and Eosinophilic Esophagitis: Two Interesting Entities Identified in the Same Patient

We illustrate the case of a 41-year-old male with allergic manifestations since childhood. He sought medical attention for intermittent, progressive dysphagia from which he had been suffering for a number of years, having felt the sensation of a retrosternal lump and a self-limited obstruction to the passage of food. Endoscopy detected a submucosal tumor in the upper third of the esophagus, which was typified, via biopsy, as a granular cell tumor with benign characteristics and probably responsible for the symptoms. Two years later, the patient sought medical attention once again as these symptoms had not abated, hence digestive endoscopy was repeated. This revealed stenosis of the junction between the middle and lower thirds of the organ which had not been detected previously but was passable under gentle pressure. Eosinophilic esophagitis was detected after biopsies were taken. Esophageal manometry identified a motor disorder affecting the esophageal body. Following three months of treatment using fluticasone propionate applied topically, the symptoms went into remission, esophageal stenosis disappeared and the esophageal biopsies returned to normal. This is the first documented case of the link between granular cell tumors and Eosinophilic esophagitis, two different disorders which could cause dysphagia in young patients