To study the mechanical interactions between heart, lungs and thorax, we propose a mathematical model combining a ventilatory neuromuscular model and a model of the cardiovascular system, as described by Smith et al. (Smith, Chase, Nokes, Shaw & Wake 2004 Med. Eng. Phys.26, 131-139. (doi:10.1016/j.medengphy.2003.10.001)). The respiratory model has been adapted from Thibault et al. (Thibault, Heyer, Benchetrit & Baconnier 2002 Acta Biotheor. 50, 269-279. (doi:10.1023/A:1022616701863)); using a Liénard oscillator, it allows the activity of the respiratory centres, the respiratory muscles and rib cage internal mechanics to be simulated. The minimal haemodynamic system model of Smith includes the heart, as well as the pulmonary and systemic circulation systems. These two modules interact mechanically by means of the pleural pressure, calculated in the mechanical respiratory system, and the intrathoracic blood volume, calculated in the cardiovascular model. The simulation by the proposed model provides results, first, close to experimental data, second, in agreement with the literature results and, finally, highlighting the presence of mechanical cardiorespiratory interactions.
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http://dx.doi.org/10.1098/rsta.2009.0137 | DOI Listing |
Res Social Adm Pharm
January 2025
Institute of Health Policy, Management and Evaluation, University of Toronto, 155 College Street, Suite 425, Toronto, Ontario, M5T 3M6, Canada; Research & Innovation, North York General Hospital, 4001 Leslie Street, Toronto, Ontario, M2K 1E1, Canada.
Purpose: Diversion or theft of controlled substances is a recognized problem affecting healthcare systems globally. The purpose of this study was to develop a framework for identifying and characterizing system factors leading to vulnerabilities for diversion within hospitals.
Methods: We applied a qualitative framework method, which involved 1) compiling a list of critical diversion vulnerabilities through observations and proactive risk analyses in the inpatient pharmacy, emergency department and intensive care unit of two Canadian hospitals; 2) coding the vulnerabilities into deductively and inductively derived themes and subthemes; and 3) building a conceptual framework.
Acad Radiol
January 2025
Department of Radiology, University Hospital Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany (R.D., J.M.B., B.S., J.M., S.G., P.K., S.W., J.H., K.N., S.A., A.B.).
Rationale And Objectives: Photon Counting CT (PCCT) offers advanced imaging capabilities with potential for substantial radiation dose reduction; however, achieving this without compromising image quality remains a challenge due to increased noise at lower doses. This study aims to evaluate the effectiveness of a deep learning (DL)-based denoising algorithm in maintaining diagnostic image quality in whole-body PCCT imaging at reduced radiation levels, using real intraindividual cadaveric scans.
Materials And Methods: Twenty-four cadaveric human bodies underwent whole-body CT scans on a PCCT scanner (NAEOTOM Alpha, Siemens Healthineers) at four different dose levels (100%, 50%, 25%, and 10% mAs).
Ann Oncol
January 2025
Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Background: The availability and affordability of safe, effective cancer therapies are core requirements for effective cancer control. Global disparities exist in access, however, yielding unequal cancer outcomes. The goal of this study was to provide updated data regarding the formulary availability, out-of-pocket costs, and accessibility of cancer medicines in countries across the full spectrum of economic development areas.
View Article and Find Full Text PDFClin Lung Cancer
December 2024
Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD; The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, MD.
Objective: To determine the association between concurrent statin use with immune checkpoint inhibitors (ICIs) and lung cancer-specific and overall mortality in patients with nonsmall cell lung cancer (NSCLC).
Materials And Methods: SEER-Medicare was used to conduct a retrospective study of Medicare beneficiaries ≥65 years of age diagnosed with NSCLC between 2007 and 2017 treated with an ICI. Patients were followed from date of first ICI claim until death, 1 month from last ICI claim, or 12/31/2018, whichever came first.
ISA Trans
January 2025
Department of Electrical and Computer Engineering, National University of Singapore, 117538, Singapore. Electronic address:
For tolerant containment control of multi-agent systems, considering the challenges in modeling and the impact of actuator faults on system security and reliability, a finite index dynamic event-triggered policy iteration algorithm is proposed. This algorithm only requires input and output data, without relying on system models, and simultaneously considers the faults and energy consumption issues to improve the system reliability and save energy consumption. The conditions are provided to demonstrate the convergence and optimality of the algorithm, including a convergence speed, that is, the number of iterations required for convergence is finite.
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