The DIRC Particle Identification System for the BABAR Experiment

A new type of ring-imaging Cherenkov detector is being used for hadronic particle identification in the BABAR experiment at the SLAC B Factory (PEP-II). This detector is called DIRC, an acronym for Detection of Internally Reflected Cherenkov (Light). This paper will discuss the construction, operation and performance of the BABAR DIRC in detail

ARIA 2016: Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle

The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma a

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

CLASSIC PAPERS REVISITED Venous Air Embolism A Warning Not to Be Complacent-We Should Listen to the Drumbeat of History

ABSTRACT: Venous air embolism during neurosurgical procedures (detected by Doppler ultrasound and aspiration via a right atrial catheter) was noted in 100 of 400 patients in the sitting position, 5 of 60 patients in the lateral position, 7 of 48 patients in the supine position, and 1 of 10 patients in the monitored prone position. We confirmed venous air embolism in many of these patients by using serial technetium-microaggregated albumin lung scans. Gravitational gradients from the venous portal of entrance to the right side of the heart were as small as 5.0 cm, with aspiration of 200 ml of air occurring. Doppler ultrasonic air bubble detection and aspiration through a previously inserted right atrial catheter are critical factors in the diagnosis and treatment of this condition

Ⅵ CLASSIC PAPERS REVISITED An Early Example of Evidence-based Medicine Hypoxemia due to Nitrous Oxide

Diffusion anoxia. By Bernard Raymond Fink. ANESTHESIOLOGY 1955; 16:511-14. In 1955, Dr. Bernard Raymond Fink published his findings that described the mechanism by which hypoxemia occurred when nitrous oxide-oxygen anesthesia was discontinued and room air breathing commenced. Using an ear oximeter and brachial artery blood gases, he measured oxygen saturation in eight healthy patients who had received 75% nitrous oxide-25% oxygen for gynecologic surgery. He showed that oxygen saturation decreased from 5% to 10% and often reached a value below 90% when the patient began room air breathing after the nitrous oxide-oxygen was discontinued. The effect was seen over a 10-min period. He concluded that "anoxia arises because the outward diffusion of nitrous oxide lowers the alveolar partial pressure of oxygen." This phenomenon can become a causative factor of cardiac arrest in patients with impaired pulmonary or cardiac reserves. IN 1955, Dr. B. Raymond (Ray) Fink (1914Fink ( -2000 was faculty in the Department of Anesthesiology, Columbia University College of Physicians and Surgeons (New York, New York) when he published one of the first articles describing a mechanism by which anesthesia could cause hypoxemia. 1 At the time, cyanosis was a recognized phenomenon during recovery from general anesthesia despite apparently good ventilation. It was also recognized that this was more frequent in patients anesthetized with a nitrous oxide-oxygen mixture. There were previous reports of a decrease in arterial oxygen saturation as measured by an ear oximeter when patients began to breathe room air, especially after a nitrous oxide-oxygen anesthetic. Ray followed this simple experiment with clinical observations in eight otherwise healthy patients undergoing gynecologic surgery who were anesthetized with 75% nitrous oxide-25% oxygen supplemented with sodium thiopental. Blood oxygen saturations were measured by either a Wood ear oximeter or brachial arterial blood analysis. Removal of the facemask at the end of the nitrous oxide-oxygen anesthetic resulted in a decrease in arterial oxygen saturation from 4.5% to 10.3% with an average of 7.9%, an effect that lasted approximately 10 min. The variability of change in oxygen saturation among the patients studied was attributed to differing levels of ventilation and lung volume. Fink observed that if patients were hyperventilating, the effect would be less, and the effect would be greater in patients with low lung volumes in which to dilute the nitrous oxide. The diffuAdditional material related to this article can be found on the ANESTHESIOLOGY Web site. Go to http://www.anesthesiology. org, click on Enhancements Index, and then scroll down to find the appropriate article and link

Simulation-based Assessment in Anesthesiology Requirements for Practical Implementation

ABSTRACT Simulations have taken a central role in the education and assessment of medical students, residents, and practicing physicians. The introduction of simulation-based assessments in anesthesiology, especially those used to establish various competencies, has demanded fairly rigorous studies concerning the psychometric properties of the scores. Most important, major efforts have been directed at identifying, and addressing, potential threats to the validity of simulation-based assessment scores. As a result, organizations that wish to incorporate simulation-based assessments into their evaluation practices can access information regarding effective test development practices, the selection of appropriate metrics, the minimization of measurement errors, and test score validation processes. The purpose of this article is to provide a broad overview of the use of simulation for measuring physician skills and competencies. For simulations used in anesthesiology, studies that describe advances in scenario development, the development of scoring rubrics, and the validation of assessment results are synthesized. Based on the summary of relevant research, psychometric requirements for practical implementation of simulation-based assessments in anesthesiology are forwarded. As technology expands, and simulation-based education and evaluation takes on a larger role in patient safety initiatives, the groundbreaking work conducted to date can serve as a model for those individuals and organizations that are responsible for developing, scoring, or validating simulation-based education and assessment programs in anesthesiology. T HE specific purpose of this article is to provide an overview of some of the issues that must be addressed to more fully embrace simulation-based methodology in the assessment of anesthesiologists. These assessments are formative (e.g., education of residents), involving detailed participant feedback, or summative (e.g., graduation requirement and board certification), with higher stakes consequences for those who participate. The following four general areas are highlighted: defining the pertinent skills and choosing relevant simulation tasks, establishing appropriate metrics, determining the sources of measurement error in test scores, and providing evidence to support the validity of test score inferences. For each of these areas, a general discussion is integrated with a brief review and synthesis of relevant anesthesia-related investigations. Because many of the logistic impediments have been addressed as part of recently established performance-based certification and licensure examinations, 1 and the specific challenges of integrating simulation into the existing anesthesia training curricula have been noted, 2 the discussion, in both general and specific to anesthesiology, will center on psychometric issues and not those associated with test administration logistics, physical test site specifications, or curriculum development. Knowing more about the specific psychometric challenges and potential solutions allows for further expansion of simulation-based assessment in anesthesiology. Before these challenges are outlined, a brief overview of the use of simulation, in both general and specific to anesthesiology, is presented

Ⅵ CLASSIC PAPERS REVISITED The Invention and Development of Enflurane, Isoflurane, Sevoflurane, and Desflurane

Thirty-six halogenated Me Et ethers have been synthesized for evaluation as volatile anesthetics. Eleven of the ethers were too unstable to test, and, of the remaining 25, 13 had promising anesthetic properties in mice and are suitable for study in larger animals. Those ethers having one H with at least 2 halogens other than F or 2 or more H with at least one Br or Cl were the best anesthetics