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Background: Immediate changes in vascular mechanics during aortic cross-clamping remain widely unknown. By using a numerical model of the arterial network, vascular compliance and resistance can be estimated and the time constant of pressure waves can be calculated and compared with results from the classic arterial waveform analysis.
Methods: Experimental data were registered from continuous invasive radial artery pressure measurements from 11 patients undergoing vascular surgery. A stable set of beats were chosen immediately before and after each clamping event. Through the arterial waveform analysis, the time constant was calculated for each individual beat and for a mean beat of each condition as to compare with numerical simulations. Overall proportional changes in resistance and compliance during clamping and unclamping were calculated using the numerical model.
Results: Arterial waveform analysis of individual beats indicated a significant 10% median reduction in the time constant after clamping, and a significant 17% median increase in the time constant after unclamping. There was a positive correlation between waveform analysis and numerical values of the time constant, which was moderate (ρ = 0.51; P = 0.01486) during clamping and strong (ρ = 0.77; P ≤ 0.0001) during unclamping. After clamping, there was a significant 16% increase in the mean resistance and a significant 23% decrease in the mean compliance. After unclamping, there was a significant 19% decrease in the mean resistance and a significant 56% increase in the mean compliance.
Conclusions: There are significant hemodynamic changes in vascular compliance and resistance during aortic clamping and unclamping. Numerical computer models can add information on the mechanisms of injury due to aortic clamping.
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http://dx.doi.org/10.1016/j.jss.2019.08.009 | DOI Listing |
J Med Microbiol
September 2025
Alberta Precision Laboratories Public Health Lab, Edmonton, Alberta, Canada.
For thousands of years, parasitic infections have represented a constant challenge to human health. Despite constant progress in science and medicine, the challenge has remained mostly unchanged over the years, partly due to the vast complexity of the host-parasite-environment relationships. Over the last century, our approaches to these challenges have evolved through considerable advances in science and technology, offering new and better solutions.
View Article and Find Full Text PDFArch Orthop Trauma Surg
September 2025
Medical Faculty, University of Zurich (UZH), Zurich, Switzerland.
Background: Distal triceps tendon rupture is related to high complication rates with up to 25% failures. Elbow stiffness is another severe complication, as the traditional approach considers prolonged immobilization to ensure tendon healing. Recently, a dynamic tape was designed, implementing a silicone-infused core for braid shortening and preventing repair elongation during mobilization, thus maintaining constant tissue approximation.
View Article and Find Full Text PDFPhytopathology
September 2025
Guizhou University, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Huaxi District, Guiyang, Guizhou Province of China, Guiyang, China, 550025;
Osthole exhibits strong inhibitory activity against phytopathogenic fungi; however, its antifungal mechanism remains unclear. This study assessed osthole's inhibitory effects on several phytopathogenic fungi, revealing a half-maximal effective concentration of 70.03 μg/ml against the hyphal growth of .
View Article and Find Full Text PDFJ Acoust Soc Am
September 2025
Key Laboratory of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing 210093, China.
Rectangular horns are widely used in professional audio applications, but designing horns with desired radiation efficiency and directivity is time-consuming and often relies on empirical methods. A multimodal-based optimization approach is proposed in this study and can simultaneously improve the radiation efficiency and directivity control of rectangular horns over a wide frequency range. Based on acoustical properties accurately simulated by a discrete model, the terms in the objective function are constructed to measure radiation efficiency, penalize jagged shapes, and improve directivity control.
View Article and Find Full Text PDFBackground: Rotator cuff injuries are very common in the athletic population and both corticosteroid injections and platelets enriched plasma (PRP) are common management options used in clinical practice yet there aren't any recent systematic reviews that compare between the two, thus, this study aims to provide a high-quality systematic review of the clinical trials and the experimentation found in the literature as of yet to guide practitioners in choosing between these two management options.
Methods: This systematic review was conducted in accordance to PRISMA guidelines and was registered in PROSPERO (CRD4202461663). A comprehensive search was done in the following databases MEDLINE, Web of Science, Google Scholar.