Inverse Conduction Technique in Hankel Domain Using Infrared Thermography: Application to Droplet Stream Quenching a Metal Disk

2010 ◽  
Author(s):  
Franck Lelong ◽  
Michel Gradeck ◽  
Benjamin Re´my ◽  
Aboubacar Ouattara ◽  
Denis Maillet
Keyword(s):  
Infrared Thermography ◽  
Nuclear Reactor ◽  
Quantitative Estimation ◽  
Measurement Techniques ◽  
Non Invasive ◽  
Loss Of Coolant Accident ◽  
Key Points ◽  
Order Of Magnitude ◽  
Metal Disk ◽  
Droplet Stream

Cooling of a hot metal by a spray occurs in various situations. Such is the case for a loss of coolant accident in a nuclear reactor, where a generated spray impacts the fuel rod assemblies. Design of an experimental characterization setup for cooling a hot (600°C) disk shape Nickel sample by a stream of monodisperse droplets is presented here. Non-invasive excitation/measurement techniques have been used in order to implement an inverse technique for quantitative estimation of both wall heat flux and temperature: heating is made by induction and infrared thermography is used for rear face temperature measurement. Control and calibration of the losses are key points here: their level is of the same order of magnitude as the flux removed by the droplets. Examples of inversion are presented.

scholarly journals Non-Invasive Assessment of Mild Stress-Induced Hyperthermia by Infrared Thermography in Laboratory Mice

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 177
Author(s):  
Urša Blenkuš ◽  
Ana Filipa Gerós ◽  
Cristiana Carpinteiro ◽  
Paulo de Castro Aguiar ◽  
I. Anna S. Olsson ◽  
...  
Keyword(s):  
Infrared Thermography ◽  
Core Body Temperature ◽  
Mild Stress ◽  
Laboratory Mice ◽  
Induced Hyperthermia ◽  
Non Invasive ◽  
Body Regions ◽  
Plus Maze ◽  
Core Body ◽  
Typical Temperature

Stress-induced hyperthermia (SIH) is a physiological response to acute stressors in mammals, shown as an increase in core body temperature, with redirection of blood flow from the periphery to vital organs. Typical temperature assessment methods for rodents are invasive and can themselves elicit SIH, affecting the readout. Infrared thermography (IRT) is a promising non-invasive alternative, if shown to accurately identify and quantify SIH. We used in-house developed software ThermoLabAnimal 2.0 to automatically detect and segment different body regions, to assess mean body (Tbody) and mean tail (Ttail) surface temperatures by IRT, along with temperature (Tsc) assessed by reading of subcutaneously implanted PIT-tags, during handling-induced stress of pair-housed C57BL/6J and BALB/cByJ mice of both sexes (N = 68). SIH was assessed during 10 days of daily handling (DH) performed twice per day, weekly voluntary interaction tests (VIT) and an elevated plus maze (EPM) at the end. To assess the discrimination value of IRT, we compared SIH between tail-picked and tunnel-handled animals, and between mice receiving an anxiolytic drug or vehicle prior to the EPM. During a 30 to 60 second stress exposure, Tsc and Tbody increased significantly (p < 0.001), while Ttail (p < 0.01) decreased. We did not find handling-related differences. Within each cage, mice tested last consistently showed significantly higher (p < 0.001) Tsc and Tbody and lower (p < 0.001) Ttail than mice tested first, possibly due to higher anticipatory stress in the latter. Diazepam-treated mice showed lower Tbody and Tsc, consistent with reduced anxiety. In conclusion, our results suggest that IRT can identify and quantify stress in mice, either as a stand-alone parameter or complementary to other methods.

scholarly journals Targeting Cancer Cell Tight Junctions Enhances PLGA-Based Photothermal Sensitizers’ Performance In Vitro and In Vivo

Pharmaceutics ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 43
Author(s):  
Victoria O. Shipunova ◽  
Vera L. Kovalenko ◽  
Polina A. Kotelnikova ◽  
Anna S. Sogomonyan ◽  
Olga N. Shilova ◽  
...  
Keyword(s):  
Epithelial Mesenchymal Transition ◽  
3D Culture ◽  
Intercellular Junctions ◽  
Cell Junctions ◽  
Multicellular Spheroids ◽  
Mesenchymal Transition ◽  
Non Invasive ◽  
Order Of Magnitude

The development of non-invasive photothermal therapy (PTT) methods utilizing nanoparticles as sensitizers is one of the most promising directions in modern oncology. Nanoparticles loaded with photothermal dyes are capable of delivering a sufficient amount of a therapeutic substance and releasing it with the desired kinetics in vivo. However, the effectiveness of oncotherapy methods, including PTT, is often limited due to poor penetration of sensitizers into the tumor, especially into solid tumors of epithelial origin characterized by tight cellular junctions. In this work, we synthesized 200 nm nanoparticles from the biocompatible copolymer of lactic and glycolic acid, PLGA, loaded with magnesium phthalocyanine, PLGA/Pht-Mg. The PLGA/Pht-Mg particles under the irradiation with NIR light (808 nm), heat the surrounding solution by 40 °C. The effectiveness of using such particles for cancer cells elimination was demonstrated in 2D culture in vitro and in our original 3D model with multicellular spheroids possessing tight cell contacts. It was shown that the mean inhibitory concentration of such nanoparticles upon light irradiation for 15 min worsens by more than an order of magnitude: IC50 increases from 3 µg/mL for 2D culture vs. 117 µg/mL for 3D culture. However, when using the JO-4 intercellular junction opener protein, which causes a short epithelial–mesenchymal transition and transiently opens intercellular junctions in epithelial cells, the efficiency of nanoparticles in 3D culture was comparable or even outperforming that for 2D (IC50 = 1.9 µg/mL with JO-4). Synergy in the co-administration of PTT nanosensitizers and JO-4 protein was found to retain in vivo using orthotopic tumors of BALB/c mice: we demonstrated that the efficiency in the delivery of such nanoparticles to the tumor is 2.5 times increased when PLGA/Pht-Mg nanoparticles are administered together with JO-4. Thus the targeting the tumor cell junctions can significantly increase the performance of PTT nanosensitizers.

scholarly journals Nearfield trapping increases lifetime of single-molecule junction by one order of magnitude

2020 ◽  
Author(s):  
Albert C. Aragonès ◽  
Katrin F. Domke
Keyword(s):  
Molecular Electronics ◽  
Single Molecule ◽  
Fold Increase ◽  
Trapping Efficiency ◽  
Non Invasive ◽  
Order Of Magnitude ◽  
Molecule Junction ◽  
Single Molecule Junction ◽  
The Difference ◽  
Power Densities

Abstract Progress in molecular electronics (ME) is largely based on improved understanding of the properties of single molecules (SM) trapped for seconds or longer to enable their detailed characterization. We present a plasmon-supported break-junction (PBJ) platform to significantly increase the lifetime of SM junctions of 1,4-benzendithiol (BDT) without the need for chemical modification of molecule or electrode. Moderate far-field power densities of ca. 11 mW/µm2 lead to a >10-fold increase in minimum lifetime compared to laser-OFF conditions. The nearfield trapping efficiency is twice as large for bridge-site contact compared to hollow-site geometry, which can be attributed to the difference in polarizability. Current measurements and tip-enhanced Raman spectra confirm that native structure and contact geometry of BDT are preserved during the PBJ experiment. By providing a non-invasive pathway to increase short lifetimes of SM junctions, PBJ is a valuable approach for ME, paving the way for improved SM sensing and recognition platforms.

scholarly journals Thermal Hydraulic Analysis of a Nuclear Reactor due to Loss of Coolant Accident with and without Emergency Core Cooling System

2020 ◽  
Vol 01 (02) ◽  
pp. 53-60
Author(s):  
Pronob Deb Nath ◽  
Kazi Mostafijur Rahman ◽  
Md. Abdullah Al Bari
Keyword(s):  
Nuclear Reactor ◽  
Cooling System ◽  
Computational Study ◽  
Reactor Core ◽  
Primary Circuit ◽  
Feed Water ◽  
Pressurized Water ◽  
Loss Of Coolant Accident ◽  
Loss Of Coolant ◽  
Core Cooling

This paper evaluates the thermal hydraulic behavior of a pressurized water reactor (PWR) when subjected to the event of Loss of Coolant Accident (LOCA) in any channel surrounding the core. The accidental break in a nuclear reactor may occur to circulation pipe in the main coolant system in a form of small fracture or equivalent double-ended rupture of largest pipe connected to primary circuit line resulting potential threat to other systems, causing pressure difference between internal parts, unwanted core shut down, explosion and radioactivity release into environment. In this computational study, LOCA for generation III+ VVER-1200 reactor has been carried out for arbitrary break at cold leg section with and without Emergency Core Cooling System (ECCS). PCTRAN, a thermal hydraulic model-based software developed using real data and computational approach incorporating reactor physics and control system was employed in this study. The software enables to test the consequences related to reactor core operations by monitoring different operating variables in the system control bar. Two types of analysis were performed -500% area break at cold leg pipe due to small break LOCA caused by malfunction of the system with and without availability of ECCS. Thermal hydraulic parameters like, coolant dynamics, heat transfer, reactor pressure, critical heat flux, temperature distribution in different sections of reactor core have also been investigated in the simulation. The flow in the reactor cooling system, steam generators steam with feed-water flow, coolant steam flow through leak level of water in different section, power distribution in core and turbine were plotted to analyze their behavior during the operations. The simulation showed that, LOCA with unavailability of Emergency Core Cooling System (ECCS) resulted in core meltdown and release of radioactivity after a specific time.

Infrared Thermography as a Means of Monitoring and Preventing Sports Injuries

2017 ◽  
pp. 165-198
Author(s):  
Manuel Sillero-Quintana ◽  
Pedro M. Gomez-Carmona ◽  
Ismael Fernández-Cuevas
Keyword(s):  
Infrared Thermography ◽  
Thermal Equilibrium ◽  
Sports Injuries ◽  
Low Cost ◽  
Professional Sports ◽  
Recovery Process ◽  
Non Invasive ◽  
Healthy State ◽  
New Applications ◽  
Contact Recording

Sports injuries are one of the most important problems in sports. Moreover, professional sports injuries lead to a difficult recovery process for the athletes, reduced athletic performance, and large economic costs. Infrared thermography (IRT) is a safe, non-invasive and low-cost technique that allows for the rapid and non-contact recording of Skin Temperature (Tsk). Recent research results have demonstrated new applications for this technique; among them, the monitoring and prevention of sports injuries appears to be one of the most interesting applications. Although IRT is not as objective as other methods, it may be sufficiently accurate and reliable as a complementary tool considering the theory that musculoskeletal structures should be in thermal equilibrium when in a healthy state. Therefore, the main contribution of IRT is to help identify an injury before it occurs, providing an opportunity for preventative action.

Blood Pressure Measurement

2011 ◽  
Author(s):  
Patrick Magee ◽  
Mark Tooley
Keyword(s):  
Blood Pressure ◽  
Arterial Pressure ◽  
Pressure Measurement ◽  
Blood Pressure Measurement ◽  
Measurement Techniques ◽  
Non Invasive ◽  
Mercury Column ◽  
Arterial Pressure Measurement ◽  
Mercury Manometer

Blood pressure measurement occurs either non-invasively or invasively, and usually refers to systemic arterial pressure measurement, but can also refer to systemic venous or pulmonary arterial pressure measurement. In 1733 the Reverend Stephen Hales was the first person to measure the blood pressure in vivo in unanaesthetised horses by direct cannulation of the carotid and femoral arteries. In doing so he observed the pulsatile nature of flow in the circulation. In 1828 Poiseuille developed the mercury manometer, and used it to measure blood pressure in a dog. The mercury manometer has, of course, become the standard technique against which other techniques are compared. The earliest numerical information on blood pressure measurement came from direct rather than indirect measurement in 1856 by Faivre, using Poiseuille’s device. However, in the last part of the nineteenth century, non-invasive measurement techniques were developed. In 1903, Codman and Cushing introduced the concept of routine intraoperative blood pressure measurement, which at the time was a revolutionary concept. Nowadays it is a fundamental part of minimal monitoring criteria. There are several techniques of non-invasive BP (NIBP) measurement, all of which function by occluding the pulse in a limb with a proximal cuff, then detecting its onset again distally, on lowering the cuff pressure. Detection methods include palpation, auscultation, plethysmography, oscillotonometry and oscillometry. Accuracy of all non-invasive techniques depends on cuff size in relation to the limb concerned, and over which artery the cuff is placed. Such techniques of NIBP measurement are necessarily intermittent. Much discussion has taken place on the accuracy of these devices, and the accuracy of diastolic pressure measurements needs improving, and there are ideas proposed for new non-invasive devices [Tooley and Magee 2009]. In the absence of a stethoscope, this technique is simple and reliable. After inflating the cuff on the upper arm to a pressure of above that of systolic, the cuff is then deflated while palpating the brachial artery and the systolic pressure is measured with a mercury column at first detection of the pulse. A study by van Bergen [1954] showed that BP can be underestimated by this method by up to 25% at 120 mmHg.

Infrared Thermography as a Means of Monitoring and Preventing Sports Injuries

2021 ◽  
pp. 832-865
Author(s):  
Manuel Sillero-Quintana ◽  
Pedro M. Gomez-Carmona ◽  
Ismael Fernández-Cuevas
Keyword(s):  
Infrared Thermography ◽  
Thermal Equilibrium ◽  
Sports Injuries ◽  
Low Cost ◽  
Professional Sports ◽  
Recovery Process ◽  
Non Invasive ◽  
Healthy State ◽  
New Applications ◽  
Contact Recording

Sports injuries are one of the most important problems in sports. Moreover, professional sports injuries lead to a difficult recovery process for the athletes, reduced athletic performance, and large economic costs. Infrared thermography (IRT) is a safe, non-invasive and low-cost technique that allows for the rapid and non-contact recording of Skin Temperature (Tsk). Recent research results have demonstrated new applications for this technique; among them, the monitoring and prevention of sports injuries appears to be one of the most interesting applications. Although IRT is not as objective as other methods, it may be sufficiently accurate and reliable as a complementary tool considering the theory that musculoskeletal structures should be in thermal equilibrium when in a healthy state. Therefore, the main contribution of IRT is to help identify an injury before it occurs, providing an opportunity for preventative action.

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