Infrared Thermometer Research Articles

Effectiveness of electroacupuncture and acupuncture in alleviating cold hypersensitivity in the hands and feet: A randomized controlled trial.

Cold hypersensitivity in the hands and feet(CHHF) is a common condition that reduces the quality of life and causes daily discomfort. The current treatments are primarily pharmacological. This study aimed to expand treatment options by comparing the efficacy of electroacupuncture (EA) and acupuncture (AC) with that of no treatment (control). A three-group randomized controlled trial was conducted with 72 women diagnosed with cold hypersensitivity in the hands and feet, as confirmed by subjective symptoms and objective temperature differences. Participants were randomly assigned to the EA, AC, or control groups. Outcome measures included hand and feet visual analog scale (VAS) scores, temperature changes measured using a non-contact thermometer, and World Health Organization Quality of Life-BREF (WHOQOL-BREF) scores assessed at pretreatment (T0), posttreatment (T1), and follow-up (T2). Repeated measures ANOVA and 2-way mixed-model ANOVA were used to evaluate group, time, and interaction effects. Both the EA and AC groups showed significant improvements in hand and feet VAS and WHOQOL-BREF scores compared with those of the control group posttreatment (T1). Notably, the EA group demonstrated sustained benefits at follow-up (T2), with significant reductions in feet VAS scores and positive changes in several WHOQOL-BREF domains. Interaction effects between group and time were observed, indicating that the changes in the EA and AC groups were meaningfully different form those in the control group. The control group also exhibited a statistically significant reduction in the VAS scores at follow-up (T2), likely due to the natural variability of cold extremity symptoms and psychological factors. This study demonstrated that EA and AC are effective in alleviating the symptoms of CHHF and enhancing the quality of life compared to no treatment. EA showed long-lasting effects than those of AC, suggesting its potential to regulate the autonomic nervous system. These findings provide a foundation for expanding non-pharmacological treatment options for CHHF and offer clinical guidance on the use of EA and AC.

Self-powered wireless sensor system utilizing a thermoelectric generator for photovoltaic module monitoring application

In this work, we demonstrate a self-powered wireless PV module monitoring system that utilizes a thermoelectric generator (TEG) to convert residual thermal energy from the PV module into electrical power. We investigated the TEG performance with and without the heat sink. Results show that the temperature difference between the hot and cold sides of the TEG increased to 7.2 °C with the heat sink, compared to only 1 °C without it, at a hot side temperature of 50 °C. We integrated the TEG/heat sink with the PV module, which served as the heat source, achieving a maximum output power of 0.981 mW at a voltage of 0.06 V under a temperature gradient of 3.6 °C in a 1 sun condition. We successfully demonstrated a self-powered wireless PV monitoring sensor system by integrating a step-up voltage converter, microcontroller, IR thermometer, Bluetooth communication module, and the TEG/heat sink, which generated sufficient power for the monitoring system operation. The findings introduce a novel solution for wireless PV module monitoring that operates independently of grid connections or battery power. This innovation not only signifies advancements in renewable energy management but also opens new opportunities in the Internet of Things (IoT) sector.

Damage investigation of hybrid flax-glass/epoxy composites subjected to impact fatigue under water ageing

The aim of this study is to investigate the fatigue behaviour of hybrid flax-glass/epoxy composites under repeated impact loading subsequent to water ageing. Different plates of these composite materials were fabricated using the vacuum infusion technique. Five stacking sequences were considered: [F8], [G/F3]S, [G2/F2]S, [G3/F]S, and [G8], where F and G stand for flax/epoxy and glass/epoxy plies, respectively. Water ageing was conducted by immersing the composite specimens in tap water at room temperature for various durations, and until saturation was reached. Fatigue impact tests were carried out using three impact energies: 3, 4, and 5 J. An advanced high-resolution camera was used to monitor the evolution of damage mechanisms occurring on the non-impacted surfaces, while a laser thermometer was considered to track the temperature variations within each composite specimen. The obtained results show that flax-glass hybridization reduces the mass of absorbed water in flax/epoxy composite by up to 70%. Furthermore, there is a more pronounced decrease in longitudinal modulus and maximum stress in aged composites, with reductions of up to 70% compared to unaged ones. Additionally, visible damage occurs even at low energy levels, manifesting from the initial impacts in both aged and unaged composite laminates. Moreover, a correlation between the number of impacts to failure and the cumulative energy is revealed. Ultimately, water aging reduces the strength of the studied composite laminates and their resistance to impact fatigue. Furthermore, the hybrid laminates with high proportion of flax layers are particularly susceptible to water ageing effects.

High-Accuracy Calibration Method of a Thermal Camera Using Two Reference Blackbodies.

Body temperature is one of the most important physiological parameters of a human being used to assess his basic vital functions. In medical practice, various types of measuring instruments are used to measure temperature, such as liquid thermometers, electronic thermometers, non-contact ear thermometers, and non-contact forehead thermometers. Such body temperature measurement techniques require the connection of appropriate sensors to a person, and non-contact thermometers operate over short distances and force a specific position of the person during the measurement. As a result, using the above methods, it is practically impossible to perform body temperature measurements of a moving human being. A thermal imaging camera can be used effectively for the purpose of the temperature measurement of moving objects, but the remote measurement of a human body temperature using a thermal imaging camera is affected by many factors that are difficult to control. Accurate remote measurement of human body temperature requires a measurement system that implements a specialized temperature determination algorithm. This article presents a model of a measurement system that facilitates the development of a highly accurate temperature measurement method. For the model, its parameters were determined on the calibration stand. The correct operation of the developed method and the effectiveness of temperature measurement have been confirmed by tests on a test stand using reference radiation sources.

Up-conversion optical temperature sensing characteristics of new KBaGd(MoO4)3:Yb3+,Ho3+ phosphors

To develop new up-conversion luminescent materials for non-contact optical thermometer with high sensitivity and temperature resolution, a battery of KBaGd(MoO4)3:Yb3+,Ho3+ phosphors were fabricated through solid reaction process. The crystal structure, up-conversion luminescence, energy transfer, thermal stability and optical temperature sensing performances were studied in detail. Under 980 nm laser excitation, the KBaGd(MoO4)3:Yb3+,Ho3+ phosphor exhibits distinctive emission bands of Ho3+ at 545, 660, and 755 nm, and excellent illuminant performance. Based on the thermally coupled levels (TCLs) of Ho3+, both the relative sensitivity (Sr) and absolute sensitivity (Sa) display similar change trends, with the highest values of 6.73%/K (@298 K) and 5.69%/K (@298 K), respectively. Furthermore, the highest Sa of 13.90%/K (@623 K) and the ultimate Sr of 0.62%/K (@ 298 K) are achieved based on non-TCLs of Ho3+. Therefore, KBaGd(MoO4)3:Yb3+,Ho3+ phosphor is a promising candidate for self-referenced optical thermometry.

Influence of carbon dots integrated in Pr3+ doped gahnite nanophosphor for thermal sensing, data fortification and fingerprint visualization analysis through YOLOv8x deep learning embedded model

The remarkable optical properties of carbon dots (CDs) render them highly promising as a versatile group of carbon-based nanomaterials. Integrating hydrothermally synthesized CDs into zinc aluminate doped with Pr3+ ions (ZnAl2O4:Pr3+) nanophosphors (ZAO:Pr3+ NPs) fabricated via the solution combustion (SC) technique holds great potential. The aim of synthesizing these nanocrystals (NCs) is to explore their potential uses in optical thermometry and anti-counterfeiting (AC) measures. The synthesized nanoparticles (NPs) and nanocomposites (NCs) underwent characterization using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectra to verify their phase, morphology, particle size, oxidation state, and chemical composition. When excited at 447 nm, the Pr3+ doped ZAO: NPs exhibited an orange-red emission band at 614 nm. A remarkable enhancement in PL intensity, by a factor of 39.02 folds, is noted upon embedding CDs into the ZAO:Pr3+ NPs (CDs@ ZAO:Pr3+). The enhanced PL intensity can be ascribed to the Förster resonance energy transfer (FRET) mechanism. Even at a temperature of 423 K, the NPs retains 95.4% of its emission intensity compared to that at room temperature, showcasing exceptional thermal stability. The 5 wt% CDs@ZAO:1Pr3+ NCs demonstrate a high colour purity (CP) of 98.3%. Moreover, these NCs hold promise for optical thermometry applications across a broad temperature range spanning from 303 to 463 K. Utilizing the exceptional ZAO:1Pr3+ NPs and 5 wt% CDs@ZAO:1Pr3+ NCs, two representative white light emitting diodes (w-LEDs) have been successfully developed, boasting satisfactory luminous efficacy and colour-rendering index (CRI). This underscores their potential for high-performance w-LED applications. Simultaneously, a highly sensitive, non-contact optical thermometer has been engineered, featuring maximum relative sensitivities of approximately 44.51×10−4K−1 and 75.48×10−4K−1 at the emission intensities corresponding to 673, 693, 712 and 735 nm, respectively. We have developed a simple brush mode technique for creating a variety of patterns using the manufactured AC security ink. The latent fingerprints (LFPs) visualized using 5 wt% CDs@ZAO:1Pr3+ NCs exhibit excellent resolution and contrast, enabling the easy identification of fingerprint characteristics from levels I-III. Employing deep learning utilizing the YOLOv8x algorithm, fluorescence images of the revealed LFPs demonstrate remarkable alignment with standard controls, suggesting a high degree of similarity. In addition, the fabricated white light emitting diode (w-LED) boasts a favorable colour rendering index (Ra=87) alongside Commission International de L′Eclairage (CIE) coordinates (0.617, 0.376). Consequently, the inclusion of 5wt% CDs@ZAO:1Pr3+NPs showcases remarkable luminescent attributes and holds promising prospects across various applications.

Assessment of the accuracy and reliability of clinical thermometers for body temperature measurements at the hospital: a laboratory study

Abstract This study aims to assess the accuracy and reliability of two different types of thermometers: contact thermometers (CT) and non-contact thermometers (NCIRT) at Maharaj Nakorn Chiang Mai Hospital. The comparison method was carried out in a hospital laboratory setting and followed a specific calibration procedure. The mean readings, errors, and measurement uncertainties were reported and categorized according to the manufacturer’s labeling models. The maximum permissible errors were defined by international standards and clinical acceptances for contact and NCIRTs, respectively. The results showed that thermometers of temperature probes (PTs) provided the highest level of accuracy. When compared to a reference standard thermometer (STD), the mean errors were only 0.04 °C at the calibration point of 37.0 °C. For digital CTs, the mean error at the calibration points of 37.0 °C was 0.24 °C. Most CT models exhibited high accuracy and reliability. However, the forehead (IRFTs) and ear (IRETs) readings significantly differed from the STD, with over half of all units not meeting the ISO 80601–2–56/ASTM E1965–98 standard requirements. These results suggest that CTs and PTs are highly accurate and reliable devices for measuring body temperature. However, both IRFTs and IRETs could be useful in certain situations, such as screening many people in a short amount of time, but their accuracy should be interpreted with caution and confirmed using a more precise method if necessary.

Infrared thermography technique for detecting estrus in Surti does

The present study evaluated the potential of the infrared thermography technique for estrus detection in Surti does. Based on the presence of estrus-specific behaviour, physiological signs as well as higher LH, FSH, estrogen and lower progesterone hormone concentration, 24 Surti does were divided into two groups, viz. estrus and non- estrus does. Recording of surface temperatures, rectal and tympanic temperatures was done using an Infrared thermal camera (FLIR T420), digital thermometer and infrared non-contact tympanic thermometer, respectively. It was concluded that temperatures of the vulva, rectal surface, rectal and tympanic temperatures are significantly higher in estrus does. Further, a strong, significant positive correlation was observed between vulvar and pudendal, rectal surface temperatures, rectal temperature as well as tympanic temperature. Thus, it may be concluded that the infrared thermography technique holds the potential for detecting estrus in Surti does.

DEVELOPMENT AND PERFORMANCE EVALUATION OF A MODEL CUTTING FLUID DEVELOPED FROM SHEA BUTTER OIL

This research was carried out to develop a model cutting fluid from Shea Butter oil and evaluate its performance in relation to temperature and surface roughness when compared to a commercial cutting fluid. The effectiveness of the cutting fluid was evaluated on a mild steel using a turning operation on the lathe machine. Temperature variations during the turning operation were measured using an infra-red gun thermometer while surface roughness was evaluated by employing a surface roughness tester. In this work Taguchi method was used to guide the selection of machine parameters such as cutting speed (rev/min), feed rate (mm/rev), and depth of cut (mm). Using Minitab, the cutting temperature and resulting surface roughness were measured for both the developed cutting and commercial fluids. The results obtained for the average cutting temperature of ~ 30oC and overall surface roughness value of 0.32μm for shea butter oil show a significant difference from that of ~ 35oC and 0.47 μm respectively for commercial grade cutting fluids. These results show that the shea butter oil-based cutting fluid not only exhibits great potential but also surpasses the current capabilities of commercial cutting fluids in terms of its cooling and surface finishing performances.

Regulating the redshift of the charge transfer band edge and antithermal quenching by ion substitution strategy in YP1-xVxO4:Eu3+ phosphor

The redshift of the charge transfer band (CTB) edge of phosphor induced by temperature rise is pervasively accompanied by antithermal quenching. Accordingly, exploring the mechanism of the CTB redshift is thus not only propitious for optimizing the sensitivity of optical thermometry but also tenders a new idea for the design of antithermal quenching phosphors. Herein, a family of YP1-xVxO4:Eu3+ phosphors were designed via the V5+/P5+ ion substitution strategy. With the increase of the V5+ ratio, the relative integral intensity of the 5D0→7F2 transition multiplies from 1.25 to 28.67 times under CTB edge excitation. Moreover, by Gaussian fitting, the reduction degree of vanadate band gap energy 1E (1T1)→1B2 (1T2), 1A2 (1T1)→1B2 (1T2) increased from 0.122 eV and 0.065 eV to0.162 eV and 0.083 eV, respectively, in the range of 303–523 K. Both reveal an enhance in redshift of the excitation spectra. The decrease of charge transfer state (CTS) energy level and the alteration of photoelectron thermal population are two mechanisms that induce CTB redshift. Specifically, the decrease of the CTS level is dominant in the YPO4:Eu3+ sample, and the thermal population of the higher vibrational levels of the VO43−ground state is dominant in the presence of a tiny amount of V5+ doping. In addition, according to the experimental phenomenon, a dual-mode temperature sensing scheme based on excitation intensity ratio (EIR) and single band ratiometric (SBR) is proposed. Y0.9P0.1V0.9O4:0.1Eu3+ achieves a maximum sensitivity of Sr-max = 4.040 % K−1 and a minimum temperature determination uncertainty of δT = 0.124 K at 323 K, which excellent performance indicates that this is a promising non-contact optical thermometer.

Comparative Evaluation of Calibrated and Non-calibrated Infrared Thermometer Versus Calibrated Digital Thermometer in Healthy Volunteers and Febrile Patients in a Tertiary Care Center in Central India

ABSTRACT Body temperature is a crucial indicator in assessing human physiological activity and health, particularly in pediatric and critically ill patients. This study aimed to compare temperature recordings obtained from digital calibrated thermometers with calibrated infrared thermometers and non-calibrated infrared thermometers against calibrated ones. An observational prospective study was conducted at AIIMS Bhopal, involving volunteers and febrile patients who consented to participate. Approval was obtained from the Institutional Human Ethics Committee, and 200 participants meeting inclusion/exclusion criteria were included. Data were collected and analyzed using Microsoft Excel. Mean and variance values were computed for both volunteer and febrile patient groups. The P values in both groups were less than 0.05, indicating a significant difference between non-calibrated handheld infrared thermometers (T1), calibrated digital thermometers (T2), and their individual comparison with calibrated infrared thermometers (T3). Variance was higher in non-calibrated infrared thermometers (T1) compared to calibrated ones (T2) in both healthy volunteers and febrile patients. Pearson’s correlation coefficient analysis within the febrile patient group demonstrated a robust positive correlation among all three thermometers compared to the healthy volunteers group. The study highlights variations in temperature readings when using different thermometers, irrespective of whether the assessment is conducted on healthy volunteers or febrile patients. Notably, the strength of association is lower in healthy volunteers than in febrile patients, suggesting that the interchangeability of thermometers may be more reliable and sufficient when assessing individuals with fever. These findings underscore the importance of careful consideration and validation of thermometer choices, especially in clinical settings where accurate temperature measurement is critical.

Na5Y9F32:Yb3+/Ho3+/Tm3+ up-conversion luminescent single crystals for highly sensitive optical temperature sensor

A novel non-contact optical temperature sensor with excellent performance of its adequate temperature resolution (δ(T) = 0.017 K) and exceptional relative thermal sensitivity (Sr = 1.97% K−1) was developed based on the up-conversion fluorescence intensity ratio (FIR) of Ho3+/Tm3+/Yb3+ triply incorporated Na5Y9F32 single crystal grown by Bridgman method. The up-conversion (UC) emission bands at 482 nm/669 nm/700 nm of Tm3+ and 522 nm/542 nm/653 nm of Ho3+ ions were observed upon excitation of 980 nm. The effects of Yb3+ concentration from 0.5 to 4 mol% on the UC emission of the Ho3+/ Tm3+ fixed doped Na5Y9F32 single crystal were also carried out. It has been demonstrated through the calculation of the steady-state rate equation that the intensity of UC emission is linearly heightened with the pump power, confirming the conversion mechanism. The temperature sensing performance of the Ho3+/Tm3+/Yb3+ incorporated Na5Y9F32 single crystals was explored by analyzing the FIR employing thermally coupled energy levels (TCLs) and non-thermally coupled energy levels (NTCLs). The maximum values of absolute sensitivity (Sa) and relative sensitivity (Sr) of the material are estimated to be 19.1% K−1 (323 K) and 1.97% K−1 (398 K), separately, which are far higher than those of previously reported RE3+-doped UC optical temperature sensor materials. This study shows that the transparent single crystal has the great potential as a non-contact optical thermometer, and provides a new idea for studying other highly optical sensing materials.

Metoda pomiaru temperatury ciała człowieka za pomocą kamery termowizyjnej

Measurement and monitoring of human physiological parameters play an important role in many applications such as health care, sports training and prevention of disease spread. Dynamic changes in physiological parameters can reveal not only changes in a patient’s physiological state and function, but also be used to assess a person’s activity status, fitness and fatigue. Body temperature is among the most important human physiological parameters for assessing basic vital functions, apart from heart rate, blood pressure and respiratory rate. In medical practice, various types of measuring instruments are used to measure temperature, such as liquid thermometers, electronic thermometers, non-contact ear thermometers, non-contact forehead thermometers. Liquid and electronic thermometers require the appropriate sensors to be connected to a person, which may be undesirable or impossible as, for example, in newborns or during sports training. Non-contact thermometers operate over short distances and often force a specific position of the person during the measurement. In addition, the above body temperature measurement techniques require direct supervision by medical personnel, which often reduces the effectiveness and efficiency of screening temperature measurement. In screening temperature measurements of a large number of people, especially those on the move, a measuring thermal imaging camera works well. The article presents a method for measuring human body temperature using a thermal imaging camera. The presented method is characterized by high accuracy of temperature measurement, which allows medical use of the obtained measurements. The measurement method has been tested on a test stand and for a selected test sample of people. The measurements and tests carried out confirmed the possibility of obtaining temperature measurement accuracy with an expanded uncertainty of less than 0.05 K with a resolution of less than 0.1 K.

Charge compensation improves energy transfer to realize anti-thermal-quenching and enhances the CaMoO4: Sm3+ phosphors optical temperature measurement sensitivity base on the FIR model

Luminescent materials are the main focus of non-contact thermometers due to their high detection sensitivity, non-invasiveness, quick reaction, exceptional stability. It is still difficult to design high sensitivity optical temperature sensors using fluorescence intensity ratio technology. This article increases fluorescence intensity ratio value and obtains high sensitivity temperature sensitive phosphors by utilizing the anti-thermal-quenching effect of rare earth luminous centers. Sm3+ and alkali metal co-doped CaMoO4 phosphors have been prepared by high-temperature solid-state method. Rietveld refinement results showed that the co-doping of Sm3+ and K+ can significantly improve the energy transfer from the host to Sm3+ and significantly increase the luminous intensity of Sm3+. We found that co-doping of Sm3+ and K+ not only effectively enhanced the luminescence intensity, but also regulated the lifetime of this phosphors. When K+ is introduced into the CaMoO4: 0.02Sm3+, the τ value decreased from 4.12 to 3.54 ms, which proves to be effective in light-emitting diode. The optical temperature measurement of CaMoO4: 0.001Sm3+, 0.001 K+ was studied using fluorescence intensity ratio technology. The maximum SaMAX and SrMAX values are 0.27 K−1 at 483 K and 2.25 % K−1 at 363 K, respectively. Moreover, the CaMoO4: 0.02Sm3+, 0.02 K+ also has a certain absorption capacity in visible optical drive, which proved by ultraviolet visible diffused reflectance spectra. The electronic density of states of phosphors are drawn via first-principles to understand the effect of Sm3+ and alkali metals co-doped on luminescence. The above results demonstrate that the Sm3+ and K+ co-doping CaMoO4 might be an attractive material for the application of temperature measurement and light-emitting diode.

Temperature sensing materials based on the fluorescence intensity ratio in Li2Ba5W3O15:Dy3+ phosphors

One of the interesting uses of phosphors is the development of non-contact thermometers apart from their usage as visible photonic devices. A series of Dy3+-doped Li2Ba5W3O15 (LBW) phosphors were successfully synthesized using high temperature solid-state reaction process. The crystal structure and morphology of LBW:xDy3+ phosphors were studied using X-ray diffraction (XRD), Rietveld refinements and field effect scanning electron microscopy (FE-SEM) with energy dispersive x-ray (EDX) analysis. The XRD and photoluminescence (PL) analyses validated the effective substitution of Ba2+ ions with Dy3+ ions. Two prominent emission peaks were found at 493 and 583 nm corresponding to 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions respectively under 368 nm excitation wavelength. A comprehensive analysis has been carried out on the usage of the Dy3+ doped LBW phosphors in fluorescence intensity ratio (FIR) thermometry. The optical temperature measurement performance of the LBW:xDy3+ phosphor was achieved by utilizing distinct thermal quenching transitions, specifically on 4F9/2→6H15/2,13/2, at temperatures ranging from 293 to 443 K. The as-prepared phosphors demonstrate excellent performance as optical thermometers, with a maximum relative sensitivity (Sr) of 0.7% K−1 at 293 K, an absolute sensitivity (Sa) of 4.68 K−1 at 443 K and a temperature resolution of ∼0.51 at 443 K. These values indicate that the phosphors are highly responsive to changes in temperature, making them suitable for non-contact thermometry applications.

Comparison of Body Temperature Values Measured With Noncontact Forehead Thermometer and Tympanic Thermometer in Adult Individuals.

Background and Purpose: Noncontact forehead thermometers have become increasingly widespread because of their advantages, such as rapid measurement of temperature, noninvasiveness, ease of use, and portability. The aim of the study was to compare the body temperature values measured using a noncontact forehead thermometer and a tympanic thermometer. Methods: A cross-sectional, comparative, and quasiexperimental research design was used in this study. The research population was composed of 200 adult individuals older than 18 years who were being treated at the hospital between January 2015 and March 2015. The temperature and humidity of the environment were measured with an electronic thermo-hygrometer. The body temperature of the patient was measured with both a noncontact forehead thermometer and a tympanic thermometer by the same researcher. The data were recorded in the patient information form and the patient observation form. Results: Mean body temperature values measured with a noncontact forehead thermometer and a tympanic thermometer were 36.17°C ± 0.47°C and 36.89°C ± 0.44°C, respectively. Results showed that there was no clear relationship between differences and averages, and there was conformity between the two methods. Conclusions: The mean forehead temperature is lower than the tympanic temperature, and there is conformity between the two methods.

Temperature sensing performance of M2La8(SiO4)6O2:Ce3+(M=Ca, Sr, Ba) based on fluorescence intensity ratio of dual emission centers in different coordination environments

Rare earth doped luminescent sensing materials as non-contact thermometers have attracted extensive research interests due to their wide applications in areas like military, medical care, aerospace, etc. How to expand the working temperature range and improve the sensitivity has become the focus. In this work, we synthesized a series of apatite-structured luminescent temperature sensors M2La7.9Ce0.1(SiO4)6O2 (M = Ca, Sr, Ba) via isomorphic substitution. By monitoring the differential changes of emission intensities from Ce3+ at the 7-coordinate and 9-coordinate site respectively when temperature varies, the real-time temperature can be determined. These materials were proven to possess the maximum absolute sensitivity up to 0.825 × 10−3 K−1, 2.63 × 10−3 K−1 and 4.33 × 10−3 K−1, respectively. Meanwhile interesting regular patterns were observed for their temperature sensitivities with the substitution of Ca, Sr and Ba. Furthermore, through studying the temperature sensitivity of Ba2La8(SiO4)6O2:xCe3+ samples with different concentrations, it was found that when the Ce3+ content was at the optimal doping concentration of 0.7, the absolute sensitivity of the sample reached 14.64 × 10−3 K−1 at 573 K. This finding has opened up a new avenue for designing fluorescent temperature sensors.

Influence of the sampling time interval of canopy temperature on the dynamic zoning of variable rate irrigation

Generating spatial distribution maps of canopy temperature (Tc) is the basis for the dynamic management of a variable rate irrigation (VRI) system based on infrared thermometers (IRTs). To improve the accuracy of management zone delineation based on Tc maps for summer maize and winter wheat with IRTs mounted on a moving sprinkler irrigation system, the influence of sampling time interval of Tc was studied and the VRI prescription maps were compared with those obtained from unmanned aerial vehicle (UAV) thermal imaging on the same day. The experimental sites were located in Shunyi, Beijing, for summer maize and in Dacaozhuang, Hebei Province, for winter wheat. The sampling time intervals were selected as 0.5–26 min. The results demonstrated that the nRMSE of the predicted and measured values for Tc increased and that their correlation coefficient decreased with the extension of the sampling time interval. When the sampling time interval ranged from 0.5 to 5 min, the correlation coefficient and nRMSE between the predicted and measured values for Tc changed little, and the overlap percentage of the same management zones delineated with NRCT between 5 min and the minimum sampling time interval (0.5 or 1 min) was greater than 79%. For any two measuring dates of Tc, their overlap percentage changed greatly, with a maximum value of 67% for NRCT. The average irrigation amount based on the prescription maps of the IRTs system and UAV thermal imaging system on the three observation days was equal. Our results demonstrated techniques to collect IRTs data and to generate VRI prescription map based on this data, and a sampling time interval of no more than 5 minutes was recommended for Tc.

Clinical value of foot thermometry in patients with acute limb ischemia.

We hypothesized that the severity of foot poikilothermy can be used for better differentiation of grades of acute limb ischemia. Thus, the study aim was evaluation of the value of non-contact foot thermometry, performed using a low-cost infrared medical thermometer, as an adjunct for clinical diagnosis of immediately threatened acute limb ischemia. It was a single-center observational prospective study performed over 3years. Patients with acute limb ischemia of lower limbs grade I-IIB Rutherford treated with urgent revascularization were included. Grade of ischemia was determined independently by two experienced vascular surgeons. Thermometry of the ischemic foot was performed using a medical digital infrared non-contact thermometer (CK-T1501, Cooligg, China) with measuring accuracy of ±0.2°C. Temperature was measured in three points: the dorsal surface of the foot, plantar surface of the foot (both in the metatarsal region), and forehead. The maximal temperature gradient between patient's forehead and foot (∆Tmax F-F) was calculated. Measurements were repeated 6-12h after revascularization. A total of 147 patients were included. Only 3 (2%) patients presented rest pain without sensory loss and motor deficit, while the majority were diagnosed with mild (63/147, 42.8%) or moderate (27/147, 18.3%) motor deficit. The temperature of the ischemic foot varied from 20 to 36.1°C, while median value of the temperature was 26.7 [24.5-29.9] °C on the dorsal surface and 26.8 [24.5-29.6] °C on the plantar surface of the foot (p = 0.85). Patients with Grade IIB ischemia had significantly lower dorsal foot temperature, plantar foot temperature, and larger ∆Tmax F-F than the patients with grades I-IIA: 25.1 [23.9-26.8] °C versus 29.9 [27.6-30.8] °C; 25.2 [23.8-27.5] °C versus 29.6 [28-31.1] °C; and 11.6 [9.7-12.8] °C versus 7.2 [6-9] °C (p < 0.0001). Areas under ROC curve for diagnosis of Grade IIB ischemia were similar for dorsal foot temperature (0.82), plantar temperature (0.81), and ∆Tmax F-F (0.82). The best cutoff value by Youden was ≥9.5°C for ∆Tmax F-F, ≤26.8°C for dorsal, and ≤27.7°C for plantar temperature. Criterion ∆Tmax F-F offered the highest specificity of 86% (95%CI 74.2-93.7) and positive predictive value of 89.2% (95%CI 79.5-93.2), while plantar temperature offered sensitivity of 82.5% (95%CI 70.1-91.3) and negative predictive value of 69.1% (95%CI 57.6-83.2). In multivariate analysis including age, gender, and etiology of arterial occlusion, the criterion ∆Tmax F-F of ≥9.5°C was a unique variable significantly associated with risk of amputation (adjusted OR 2.6, 95%CI 1.2-5.9, p = 0.01). Current study demonstrated that patients with immediately threatening ALI have significantly lower foot temperature than those with viable and marginally threatened limbs. Severe foot poikilothermy at admission is associated with poor outcomes of revascularization, mostly with limb loss.

Assessment of preferable site for temperature measurement using non-contact infra-red temperature among pediatric patients.

Accurate temperature measurement with little or no discomfort that is safe, without risk of hospital-acquired infections or perforations, is the preferred choice of medical professionals in pediatric settings. The objective was to discover the preferable site for body temperature measurement using non-contact infra-red thermometer (NCIT) among pediatric patients. NCIT measurement at mid forehead (F), right temporal region (T), right side of neck-over-carotid artery area (N), jugular notch (J), sternum (S), umbilical region and sublingual region (U) were compared with digital axillary temperature (DAT) in a single attempt in 500 patients, aged between 2 to 5 years with fever. Data was analyzed using Pearson's correlation, paired t-test and Bland-Altman plot to assess the correlation and agreement between the DAT and NCIT sites. The mean temperature of NCIT-T (38.42±0.64 °C) was more agreeable with DAT (38.42±0.63 °C) compared to other body sites. The minimum mean bias of -0.00480 °C was noted for NCIT-F with 95% CI of -0.164-0.15; however, NCIT-F revealed many outliers as compared to NCIT-J. A strong positive correlation existed between DAT and NCIT sites (r value: 0.99-0.98). However, significant difference was found between DAT and NCIT-N, NCIT-F and NCIT-U (P<0.0001). NCIT-J is the most preferable choice for measuring body temperature and can be interchanged with DAT. It will help to deliver fast results with enhanced patient comfort due to its non-invasive nature.