The design of a fibre Bragg grating based manometry catheter for in-vivo diagnostics in the human colon is presented. The design is based on a device initially developed for use in the oesophagus, but in this instance, longer sensing lengths and increased flexibility were required to facilitate colonoscopic placement of the device and to allow access to the convoluted regions of this complex organ. The catheter design adopted allows the number of sensing regions to be increased to cover extended lengths of the colon whilst maintaining high flexibility and the close axial spacing necessary to accurately record pertinent features of peristalsis. Catheters with 72 sensing regions with an axial spacing of 1 cm have been assembled and used in-vivo to record peristaltic contractions in the human colon over a 24hr period. The close axial spacing of the pressure sensors has, for the first time, identified the complex nature of propagating sequences in both antegrade (towards the anus) and retrograde (away from the anus) directions in the colon. The potential to miss propagating sequences at wider sensor spacings is discussed and the resultant need for close axial spacing of sensors is proposed.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OE.17.022423 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Large stroke radially oriented MXene composite fiber tensile artificial muscles.
Sci Adv
January 2025
School of Chemistry, Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education, Beihang University, Beijing 100191, China.
Actuation is normally dramatically enhanced by introducing so much yarn fiber twist that the fiber becomes fully coiled. In contrast, we found that usefully high muscle strokes and contractile work capacities can be obtained for non-twisted MXene (TiCT) fibers comprising MXene nanosheets that are stacked in the fiber direction. The MXene fiber artificial muscles are called MFAMs.
View Article and Find Full Text PDFHindlimb locomotor biomechanics of the derived therizinosaur Nothronychus: Functional changes in the line to birds and convergence with large-bodied neornitheans.
Anat Rec (Hoboken)
December 2024
Biology Department, Northland Pioneer College, Holbrook, Arizona, USA.
Nothronychus graffami was a large therizinosaur represented by a single well-preserved individual from the Turonian Tropic Shale of southern Utah. It is characterized by an enlarged abdomen, small tail, and an extensively pneumatized axial skeleton, and is frequently regarded as herbivorous. Given the overall tail reduction and the development of a wide fused synsacrum with widely spaced acetabulae, it is reconstructed with an anteriorly rotated femur and a displaced resting ground reaction force anterior to the center of mass.
View Article and Find Full Text PDFA computational framework to optimize the mechanical behavior of synthetic vascular grafts.
J Mech Behav Biomed Mater
December 2024
Department of Biomedical Engineering, The University of Utah, 36 S Wasatch Dr, Salt Lake City, UT, 84112, USA; Department of Biomedical Engineering, Texas A&M University, 101 Bizzell St, College Station, TX, 77843, USA; Scientific Computing and Imaging Institute, The University of Utah, 72 Central Campus Dr, Salt Lake City, UT, 84112, USA; School of Engineering Medicine, Texas A&M University, 1020 Holcombe Blvd., Houston, TX, 77030, USA; Department of Multidisciplinary Engineering, Texas A&M University, 101 Bizzell St, College Station, TX, 77843, USA; Department of Cardiovascular Sciences, Houston Methodist Academic Institute, 6565 Fannin Street, Houston, TX, 77030, USA. Electronic address:
The failure of synthetic small-diameter vascular grafts has been attributed to a mismatch in the compliance between the graft and native artery, driving mechanisms that promote thrombosis and neointimal hyperplasia. Additionally, the buckling of grafts results in large deformations that can lead to device failure. Although design features can be added to lessen the buckling potential (e.
View Article and Find Full Text PDFA multimodal axial array resonator and its application in radiofrequency (RF) volume coil designs for low-field open magnetic resonance imaging (MRI).
Quant Imaging Med Surg
December 2024
Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, USA.
Background: Low-field open magnetic resonance imaging (MRI) systems, typically operating at magnetic field strengths below 1 Tesla, has greatly expanded the accessibility of MRI technology to meet a wide range of patient needs. However, the inherent challenges of low-field MRI, such as limited signal-to-noise ratios and limited availability of dedicated radiofrequency (RF) coils, have prompted the need for innovative coil designs that can improve imaging quality and diagnostic capabilities. In this work, we introduce a multimodal axial array resonator and its implementation in a volume coil, or referred to as a coupled stack-up volume coil, to address these challenges in low-field open MRI.
View Article and Find Full Text PDFBearing Characteristics of Screw-Groove Piles: Model Test and Numerical Analysis.
Materials (Basel)
November 2024
School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Screw-groove piles, a new type of precast pile, are economically and environmentally friendly and improve the load-bearing performance of piles through a unique screw-groove structure. To reveal the load-transfer characteristics and bearing mechanism of the screw-groove pile, the axial force, load-settlement curve, skin friction, bearing capacity, and response characteristics of the foundation for piles under vertical loading were analyzed. Furthermore, a parameter analysis of the ultimate bearing capacity and material utilization of screw-groove piles was performed using the finite element method.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!