269 research outputs found

    Proof-of-principle validation of a novel intraluminal optical sensor for dynamic monitoring of intestinal anastomosis: An in vivo animal model case study

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    Intestinal resections are commonly performed to treat different colorectal conditions, including colorectal cancer. A successful primary anastomosis is the desired optimal outcome after intestinal resection. Maintaining adequate blood flow across the anastomosis is paramount for reducing anastomotic failure. Currently, there are no clinical devices capable of continuously assessing blood flow and blood perfusion at an anastomosis during and after surgery. The aim of this study was to develop an indwelling optical sensor for the monitoring of perfusion biomarkers using photoplethysmography and near-infrared spectroscopy principles. In an animal in-vivo proof-of-principle study, it was found that the developed sensor performed appropriately for the assessment of blood flow and perfusion in an anastomosis, showing changes in the assessed parameters after gradual devascularization of the transected bowel

    Measuring thermal conductivity in freezing and thawing soil using the soil temperature response to heating

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    The thermal conductivity of the thin seasonally freezing and thawing soil layer in permafrost landscapes exerts considerable control over the sensitivity of the permafrost to energy and mass exchanges at the surface. At the same time, the thermal conductivity is sensitive to the state of the soil, varying, for example, by up to two orders of magnitude with varying water contents. In situ measurement techniques perturb the soil thermally and are affected by changes in soil composition, for example through variations in thermal contact resistance between sensor and soil. The design of a sensor for measuring the temperature of the soil rather than the axial heating wire temperature has consequences for the modeling of heat flow. We introduce an approximation of heat flow from a heated cylinder with thermal contact resistance between the cylinder and the surrounding medium. This approximation is compared to the standard line source approximation, and both are applied to data measured over a one-year period in northern Alaska. Comparisons of thermal conductivity values determined numerically using the line source solution, line source approximation and the analytical form of the heated cylinder model fall within 10% of accepted values, except for measurements made in pure ice, for which all methods of calculation under-predicted the thermal conductivity. Field data collected from a complete freeze¿thaw cycle in silty clay show a seasonally bimodal apparent thermal conductivity, with a sharp transition between frozen and thawed values during thaw, but a three-month transition period during freezing. The use of soil composition data to account for changes in heat flow due to the effect of latent heat during phase change results in a relationship between soil thermal conductivity and temperature

    Sensors 2020 Best Paper Awards

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    Sensors is instituting the Best Paper Award to recognize outstanding papers published in the journal [...

    RETRACTED: Qian et al. Information System Model and Key Technologies of High-Definition Maps in Autonomous Driving Scenarios. Sensors 2024, 24, 4115

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    The Journal retracts the article titled “Information System Model and Key Technologies of High-Definition Maps in Autonomous Driving Scenarios” [...

    Acknowledgment to the Reviewers of Sensors in 2022

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    High-quality academic publishing is built on rigorous peer review [...

    Acknowledgment to Reviewers of Sensors in 2021

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    Rigorous peer-reviews are the basis of high-quality academic publishing [...

    Acknowledgment to Reviewers of Sensors in 2020

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    Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Sensors maintains its standards for the high quality of its published papers [...
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