. In laser lithotripsy, a green aiming beam overlying the infrared (IR) treatment radiation gives rise to reflection and fluorescence signals that can be measured via the treatment fiber. While stone autofluorescence is used for target detection, the condition of the fiber can be assessed based on its Fresnel reflection. For good applicability, fluorescence detection of stones should work even when the stone and fiber are not in direct contact. Fiber breakage detection, on the other hand, can be falsified if surfaces located in front of the fiber reflect light from the aiming laser back into it. For both applications, therefore, a fundamental investigation of the dependence of the signal amplitude on the distance between fiber and surface is important.. Calculations of the signal drop of fluorescence or diffuse and specular reflection with increasing fiber distance were performed using ray tracing based on a simple geometric model for different fiber core diameters. Reflection signals from a mirror, diffuse reflector, human calculi, and porcine renal tissue placed in water were measured at varying distances (0-5 mm). For human calculi, fluorescence signals were recorded simultaneously.. The calculations showed a linear signal decrease down to ∼60% of the maximum signal (fiber in contact). The distanceat which the signal drops to for example 50% depends linearly on the diameter of the fiber core. For fibers used in lithotripsy and positioned in water,ranges from 0.55 mm (200m core diameter) to 2.73 mm, (1 mm core diameter). The calculations were in good agreement with the experimental results.. The autofluorescence signals of stones can be measured in non-contact mode. Evaluating the Fresnel signal of the end face of the fiber to detect breakage is possible unless the fiber is situated less than some millimeters to reflecting surfaces.
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http://dx.doi.org/10.1088/2057-1976/ac82c7 | DOI Listing |
ACS Appl Mater Interfaces
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Textile and Clothing College, Qingdao University, Qingdao 266071, China.
Fiber-based strain sensors, as wearable integrated devices, have shown substantial promise in health monitoring. However, current sensors suffer from limited tunability in sensing performance, constraining their adaptability to diverse human motions. Drawing inspiration from the structure of the spiranthes sinensis, this study introduces a unique textile wrapping technique to coil flexible silver (Ag) yarn around the surface of multifilament elastic polyurethane (PU), thereby constructing a helical structure fiber-based strain sensor.
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Department of Pathology and Genomic Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
Background: The FOXOs regulate the transcription of many genes, including ones directly linked to pathways required for lens development. However, this transcription factor family has rarely been studied in the context of development, including the development of the lens. FOXO expression, regulation, and function during lens development remained unexplored.
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Tropical Feed Resources Research and Development Center (TROFREC), Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand.
The objective of this study was to examine the impact of black soldier fly larval oil (BSFO) on feed consumption, nutritional digestibility, ruminal characteristics and methane (CH) estimation in Thai-indigenous steers. Four male Thai native steers (Bos indicus) weighing 383 ± 9.0 kg were used in this investigation.
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Department of Neurology, National Institute of Medicine of the Ministry of Interior and Administration, 02-507 Warsaw, Poland.
Age-related changes to the orbicularis oculi muscle include impaired eyelid function, such as lagophthalmos, alterations in tear film dynamics, and aesthetic changes like wrinkles, festoons, and the descent of soft tissue. To date, the structural and functional changes that would comprehensively increase our understanding of orbicularis aging have not been analyzed. This study aims to investigate functional outcomes using surface electromyography and correlate them with ultrastructural changes in orbicularis during aging.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Mechanical Engineering, Politecnico di Milano, Via G. La Masa 1, 20156 Milano, Italy.
In naval engineering, particular attention has been given to containerships, as these structures are constantly exposed to potential damage during service hours and since they are essential for large-scale transportation. To assess the structural integrity of these ships and to ensure the safety of the crew and the cargo being transported, it is essential to adopt structural health monitoring (SHM) strategies that enable real-time evaluations of a ship's status. To achieve this, this paper introduces an advancement in the field of smart sensing and SHM that improves ship monitoring and diagnostic capabilities.
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