Measurement Method Research Articles

Length of seminiferous tubules or epididymal duct estimated with profile counting or diameter measurement: a stereological comparison with transverse and isotropic sections

Transverse testicular sections are often used for histopathological studies and length of seminiferous tubules in the testis is often estimated with a stereological method of tubule diameter measurement, i.e. estimated by the tubule volume divided by the tubules’ cross-sectional area that is estimated with measurement of round or elliptical tubule profiles’ (short axial) diameters. But unbiased stereological length estimation is best based on counting of tubule profiles on isotropic sections. To determine the bias of length estimation with diameter measurement, (i) transverse sections (methacrylate embedded) were obtained from a testis of each normal mature male Sprague-Dawley rat (10 rats in total) and isotropic sections obtained (with the orientator) from the other testis of the rat, and (ii) the tubule length densities were estimated with both methods of profile counting and diameter measurement. The results demonstrated that the method of diameter measurement on transverse or isotropic sections overestimated the length density by 20%-25% compared with profile counting on isotropic sections, probably mainly because of underestimation of the tubules’ cross-sectional area estimated from the short-axial diameters. Length density of the epididymal duct in the epididymis was also estimated with profile counting in the present study, using transverse and isotropic sections for comparison, and significant statistical difference was not found between the results obtained with the transverse and isotropic sections.

Cellular senescence in acute human infectious disease: a systematic review

IntroductionAcute infectious disease represents a significant cause of mortality and morbidity in elderly individuals admitted to the hospital. In its extreme, it presents as sepsis, a systematic inflammatory and immunologic response responsible for self-injurious organ injury. As individuals age, a unique set of factors including immunosenescence predispose them to acquiring an infection and a worse clinical prognosis. This systematic review explores the relationship between cellular senescence, an age-related inflammatory phenomenon, with acute human infectious disease.MethodsEmbase via OVID, Scopus, Web of Science, Global Index Medicus, Cochrane Library via Wiley, and ClinicalTrials.gov were queried. Included studies must have compared at least one of the following measures of cellular senescence between patients with an infection and without an infection: cell cycle inhibition measured via levels of p16INK4a and/or p21CIP1, short telomere length, DNA damage via ɣH2AX, high senescence-associated β galactosidase activity, and inflammation via the detection of senescence associated secretory phenotype (SASP). Manuscripts were screened and data collected via two independent reviewers.ResultsA total of 15,828 studies were screened after duplicates were removed. One hundred and fifty-three full-text articles were assessed for eligibility and a total of 16 original articles were included in analysis. Of the 16 original articles included, 12 (75%) articles were centered on SARS-CoV-2, 2 (12.5%) articles utilized patients infected with Leishmania braziliensis, 1 (6.25%) with Plasmodium falciparum, and 1 (6.25%) with Hepatitis C.ConclusionCurrent literature demonstrates robust upregulation of markers of cellular senescence in the setting of acute SARS-CoV-2, P. falciparum, L. braziliensis, and hepatitis C virus, and that markers of senescence correlate with disease severity and persist for months after resolution. Limitations in the number and types of infectious organisms studied, low sample sizes, modest longitudinal sampling, and a lack of consistency in markers measured, the method of measurement, and the definition of normal values represent ongoing gaps in the literature.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?RecordID=421473, Identifier CRD42023421473.

A novel method of acetabular component anteversion measurement on plain radiographs.

Acetabular component anteversion (ACA) markedly impacts the outcome of total hip arthroplasty (THA) and thus is routinely measured on radiographs postoperatively. However, clinical ACA measurement methods are either too complicated or subjective due to three drawbacks: complex calculations, measurement of obscured points, and complex geometric drawings. This study aimed to develop a precise and convenient novel method of measuring ACA on routine radiographs without the three drawbacks and to verify its accuracy and reliability by comparing it against existing methods. A novel geometric principle to measure ACA was developed. Accordingly, a protractor was designed to measure radiographic anteversion (RA) on anteroposterior (AP) hip radiographs. Three researchers measured RA twice, using the protractor, McLaren's, and Pradhan's method on 26 computer-simulated radiographs with pre-set RAs and 20 actual radiographs. Accuracy was assessed by errors on simulated radiographs, and reliability was assessed by results of measurements on simulated and actual radiographs. The absolute error of the novel method (1.01° ± 1.06°) was lower than McLaren's method (1.34° ± 1.16°) (p < 0.05) and not significantly different from Pradhan's method (1.10° ± 1.02°) (p = 0.392). The protractor's intra-rater and inter-rater reliability were good-to-excellent or excellent and higher or equivalent to the two other methods. The novel method avoids the three major drawbacks of conventional methods. Its accuracy is significantly higher than McLaren's method and comparable to Pradhan's. The novel method has higher or non-inferior accuracy and reliability than McLaren's and Pradhan's methods.

Comparison of the Physical Trace of Global Luminosity Emission at Multiwavelength and Star Formation Rates of Luminous Infrared Galaxies Using Extragalactic Distance Scale Techniques

This paper aims to study the rate of star formation (SFR) in luminous infrared galaxies at different wavelengths using distance measurement techniques (dl, dm) and to know which methods are the most accurate to determine the rate of star formation as we present through this research the results of the statistical analysis (descriptive statistics) for a sample of luminous infrared galaxies. The data used in this research were collected from the NASA Extragalactic Database (NED) and HYPERLEDA, then used to calculate the star formation rate and indicate the accuracy of the distance methods used (dl, dm). Two methods were tested on Hα, OII, FIR, radio continuum at 1.4 GHz, FUV, NUV, and total (FUV + FIR). The results showed that the dl measurement method has the most accuracy in calculating SFR as it depends on the redshift where the relationship between them is direct. while the other distance method (dm) depends on absolute blue magnitude (MB), it was somewhat less accurate, but the two methods are helpful for this type of calculation.

Optimization and application of renal depth measurement method in the cadmium-zinc-telluride‑based SPECT/CT renal dynamic imaging.

This study aims to evaluate the accuracy of four kidney depth measurement methods-nuclear medicine tomography, nuclear medicine lateral scanning, ultrasound, and Tonnesen's formula-based estimation-using CT measurements as the reference standard. Additionally, it investigates the feasibility of utilizing nuclear medicine tomography and lateral scanning for measuring kidney depth in 99mTc-DTPA renal dynamic imaging. Hollow kidney phantoms mimicking the shape and volume of adult kidneys were 3D printed and filled with 99mTcO4- solution. These phantoms were then subjected to lateral scanning and nuclear medicine tomography using CZT (cadmium-zinc-telluride) SPECT/CT to determine the optimal post-processing method. Forty patients who underwent renal dynamic imaging were recruited for the study. Renal depths were derived from ultrasound, lateral imaging, nuclear medicine tomography, formula-based estimation, and CT measurements. The renal depths obtained through these four methods were for correlation with CT-measured renal depths. Additionally, the absolute differences between renal depths obtained by each method and the CT standard were analyzed and compared across groups. Using kidney phantoms, nuclear medicine tomography images were processed with a Butterworth filter (cutoff frequency = 0.6), and renal outlines in lateral images was manually delineated. In the clinical validation phase, correlation coefficients indicated strong associations between renal depths measured by nuclear medicine tomography (left kidney: R = 0.885, P < 0.05; right kidney: R = 0.927, P < 0.05) and lateral scanning (left kidney: R = 0.933, P < 0.05; right kidney: R = 0.956, P < 0.05) compared to CT measurements. The difference in kidney depth between nuclear medicine tomography and CT measurements were the smallest and statistically significant (left kidney: 0.69 ± 0.51; right kidney: 0.58 ± 0.41, P < 0.05). Using ordered subset expectation maximization (OSEM) in conjunction with a Butterworth filter (fc = 0.6) as the post-processing method, nuclear medicine tomography enables more accurate renal depth measurements without increasing the radiation dose to patients.

Quantifying the Relationship Between Self-Efficacy and Mathematical Creativity: A Meta-Analysis

This study is a meta-analysis to examine the relationship between self-efficacy and mathematical creativity. This meta-analysis included 21 studies with a total sample size of 11,621 participants and 33 effect sizes across the studies. Data analysis using a random effects model using the “meta” package (version 7.0-0) in R software version 4.3.0. The results showed a positive and significant relationship between self-efficacy and mathematical creativity (z=3.51;95% CI [0.09, 0.32], p&lt;0.001). The influence of self-efficacy on mathematical creativity is included in the low category (re=0.21). These findings had no publication bias issues with Egger’s test (t=−0.03; p=0.978) and were stable against the impact of unpublished studies (Fail−safe N=5101; p&lt;0.001). Meta-regression revealed two variables that showed significant results: measurement method (Q=11.17;df=2; p=0.0038) and study location (Q=372.41, df=9; p&lt;0.0001). This study provides valuable information about the relationship between self-efficacy and mathematical creativity, but more research is needed to develop effective and efficient learning strategies.

Concurrent Profiling of Localized Transcriptome and RNA Dynamics in Neurons by Spatial SLAMseq.

The asymmetric distribution of RNA within a cell plays a pivotal biological role, ensuring the distinctive shapes and functionality of subcellular compartments. In neurons, these mechanisms are fundamental to cellular growth, synaptic plasticity, and information processing. To understand these mechanisms, diverse methods have been developed to analyze localized transcripts. Here, we outline our optimized method for measurement of mRNA half-lives in subcellular neuronal compartments-neurites, and cytoplasmic and nuclear fractions of cell bodies. We call this method spatial SLAMseq, as it combines SLAMseq with subcellular compartment separation techniques. Spatial SLAMseq facilitates the concurrent measurement of mRNA dynamics and steady-state RNA levels within neuronal subcellular compartments.

Does different application modes of universal adhesives with universal resin composites affect the microleakage in class V cavities? An in vitro study.

Composite restorations often have gingival margins near the cemento-enamel junction (CEJ), where the microleakage of these margins can significantly contribute to the restoration failure, especially in the cervical lesions. It is important to determine the microleakage is crucial, as it typically occurs through the interfacial gap between the tooth and the restoration. Various resin composites and techniques have been developed to minimize this gap and reduce the risk of microleakage. The aim of this in vitro study was to evaluate the levels of microleakage of different modes of a universal adhesive and two novel resin composites in restoring class V cavities in the central incisors. Sixty-six freshly extracted sound human central incisors of the similar size were randomly assigned to 2 groups (n = 33 per group) according to the brand of resin composite. Each group was further divided into 3 subgroups based on the Scotch Bond Universal (3M ESPE, Saint Paul, MN, USA) application protocol used: (a) total etch, (b) self-etch and (c) selective etch. After composite restoration completed with Omnichroma (Tokuyama Dental Corp., Tokyo, Japan) and Filtek Universal Restorative (3M ESPE, Saint Paul, MN, USA), each tooth was immersed in a 0.5% basic fuchsin dye solution at 37C0 for 24h. After dye penetration, teeth were sectioned and evaluated with conventional (scoring) and digital methods (ImageJ). The intra- and inter-examiner agreement was estimated according to the Kappa statistics and the results were analyzed with the one-way ANNOVA and the Kruskal-Wallis test (p < 0.05). The rates of microleakage of the gingival and incisal margins are statistically similar, regardless of the composite brand and the method of application of the universal adhesive. The microleakage exhibited by current adhesives and resins is independent of the adhesive application mode and measurement method.

Enhancing time-resolution for radon measurements using airflow-through scintillation cells based on a compartmental model approach.

To overcome the time-resolution limitation inherent in the airflow-through scintillation cell method for radon measurement, this study introduces a compartmental model elucidating the behaviors of radon and its progeny within such cells. The computed results of the normalized equilibrium functions derived from the compartmental model, provide quantitative insights into the equilibrium progression of 222Rn and its progeny over time, substantiating the identified time-resolution limitation of 2-3hours. Laboratory experiments confirm the efficacy of the proposed correction algorithm, showcasing its ability to surmount the time-resolution limitation and achieve a rapid response in radon measurement using airflow-through scintillation cells.

A mileage correction method of pipeline inertial measurement for dam internal deformation monitoring

Internal deformation monitoring is of great significance to the safe operation and maintenance of dams. Some scholars have carried out dam internal deformation monitoring by pipeline inertial measurement with a pipeline measurement robot, which has improved the monitoring accuracy and efficiency considerably, compared with the traditional monitoring methods. However, there are still shortcomings in this method. Because the odometer on the pipeline measurement robot will slip or slide, resulting in errors in the mileage of the multiple measurement routes, which hinders the development of the accuracy of pipeline inertial measurement. This paper proposes a mileage correction method based on junction detection to improve the accuracy of pipeline inertial measurement for better dam internal deformation monitoring. The mileage correction method establishes a reference model of pipeline junction location, detects the locations of pipeline junction welds on the measurement routes using two k-mean clustering, and corrects the odometer data based on the difference between the detected and reference locations. We evaluate the enhancement of this mileage correction method on the internal accuracy and deviation values compared with other method for pipeline inertial measurement. The proposed method is validated using measured data from the internal pipeline of Tianchi Dam. The results show that compared with the results directly fused without detection–correction, the method proposed in this paper reduces the root-mean-square error of the results by an average of 30.30% and improves the deviation compared with the reference deformation by an average of 2.3 mm. Therefore, the method has good results and practical applications.

Shape measurement by using multicore optical fiber sensor with asymmetric dual cores

Abstract Shape measurement by using multicore optical fiber sensor has attracted more attention in many fields due to the good consistency of the fiber cores. Three symmetrically arranged cores in multicore fiber are usually used for reconstructing shape by calculating the bending vectors, which will not be achieved when one of the cores is damaged or occupied in actual application. A shape measurement method using multicore optical fiber sensor with asymmetric dual cores is proposed in this paper. Based on analyzing the principle of shape reconstruction and the geometric relationship of asymmetric dual cores in multicore fiber sensor, the bending vector is decomposed. The mathematical expressions for bending curvature and orientation of asymmetric dual cores are derived. The two dimensional (2D) and three dimensional (3D) shape reconstruction results both in finite element modelling simulation and shape measurement experiment based on optical frequency domain reflectometry have shown that the proposed method using multicore fiber sensor with asymmetric dual cores is able to achieve shape measurement, and its performance is comparable and even equivalent to the traditional method by using three symmetrically arranged cores. In the experiment, the maximum relative errors of 2D and 3D reconstructed shapes are 2.653% and 5.139%, respectively. The proposed method, which only needs asymmetric dual cores in the multicore optical fiber sensor for shape reconstruction, will be conducive to solve the limitation of multicore optical fiber sensors in shape measurement applications.

Pedestrian safety alarm system based on binocular distance measurement for trucks using recognition feature analysis

AbstractAs an essential part of modern smart manufacturing, road transport with large and heavy trucks has in-creased dramatically. Due to the inside wheel difference in the process of turning, there is a considerable safety hazard in the blind area of the inside wheel difference. In this paper, multiple cameras combined with deep learning algorithms are introduced to detect pedestrians in the blind area of wheel error. A scheme of vehicle-pedestrian safety alarm detection system is developed via the integration of YOLOv5 and an improved binocular distance measurement method. The system accurately measures the distance between the truck and nearby pedestrians by utilizing multiple cameras and PP Human recognition, providing real-time safety alerts. The experimental results show that this method significantly reduces distance measurement errors, improves the reliability of pedestrian detection, achieves high accuracy and real-time performance, and thus enhances the safety of trucks in complex traffic environments.

Environmental dependence of geometrical efficiency for the scintillation cell in radon and thoron measurement.

222Rn is recognized as a matter of international concern for human health risk. Because 220Rn as well as 222Rn coexist in the natural environment, thoron sometimes influences the experiment for radon measurement. It is important to measure radon and thoron separately to evaluate the risk of the exposure to 222Rn. As a discriminative measurement method for 222Rn and 220Rn, a simple technique with a single scintillation cell is well known. However, in recent years, the influence of atmospheric environment on the geometrical efficiency of the scintillation cell has not yet been investigated. In this study, environmental dependence of geometrical efficiency for the scintillation cell in 222Rn and 220Rn measurement was investigated using the Lucas type scintillation cell and Monte Carlo particle simulation. It was found that the influence of temperature and pressure on the geometrical efficiencies were larger than that of relative humidity.

Photoelectric sensor array-based measurement method for the key motion parameters of the small flying object considering non-uniform curve trajectory

Purpose The paper aims to accurately measure the key motion parameters, such as velocity, azimuth and pitch angle, of the small flying object with a non-uniform curve trajectory. It proposes a measurement method and its calculation model of non-uniform curve trajectory using a photoelectric sensor array. Design/methodology/approach First, the basic composition of the measurement system and mechanism of photoelectric sensor array are described, respectively. Second, a non-uniform curve mathematical measurement model is constructed differently from the traditional linear trajectory, taking into account the influence of gravity and air resistance. Third, the measurement error of the system is analyzed through numerical simulation. Finally, the accuracy and feasibility of the approach are verified by live-ammunition experiments. Findings The results show that the systematic error of the hitting point coordinates can be reduced by 9% compared to the traditional linear measurement model. Consequently, this method can meet the higher measurement requirement for the key motion parameters of the small flying object under the non-uniform curve trajectory. Research limitations/implications (if applicable)- although the approach itself is generalizable, the method is unable to detect the motion parameters of multiple small flying objects. Research limitations/implications Although the approach itself is generalizable, the method is unable to detect the motion parameters of the multiple small flying objects. Practical implications It is evident that the proposed non-uniform curve measurement model is more precise in quantifying the essential characteristics of the small flying object, particularly in consideration of the environmental conditions. Social implications The precise measurement of the key motion parameters of the small flying object can facilitate the enhancement of the protective performance of protective materials. Originality/value A novel approach to measurement is proposed, which differs from the conventional uniform trajectory model. To this end, the space construction of the photoelectric sensor array is optimized. The number of the sensors is revised.

Blade tip clearance measurement method based on blade tip timing without the once per revolution sensor

Abstract The rotor blade tip clearance (BTC) of an aeroengine is a critical parameter that significantly impacts its performance and safety. Accurately determining dynamic BTC has been a focal point of research in experimental testing. Among the effective measurement methods for dynamic BTC, the laser triangulation method based on blade tip timing (BTT) stands out. However, this method typically relies on an once-per-revolution (OPR) sensor for rotor speed and blade serial number information during measurement, leading to increased installation and maintenance costs as well as additional measurement uncertainties. In response to this challenge, this paper presents two signal processing method that eliminate the need for an OPR sensor. The first method, referred to as "none OPR method 1," closely follows the measurement principles of the traditional method but employs a skewed dual light probe (SDLP) signal to extract rotational speed information, thus obviating the need for an OPR sensor. The second method, "none OPR method 2," introduces a novel data processing approach that enables BTC determination without any source of rotor speed information. Both methods utilize dynamic and static BTC matching techniques to identify blade serial numbers and achieve BTC measurement without an OPR sensor on a simulated rotor experimental bench. Comparative analysis with traditional method BTC measurements reveals that, under stable rotor speeds, all methods achieve similar levels of accuracy and repeatability errors within 0.025mm. However, when dealing with variable speed conditions, the traditional method's accuracy is significantly affected. None OPR method 1 mitigates the impact of rotor speed changes to some extent, while none OPR method 2 remains unaffected by such changes. Importantly, both none OPR methods demonstrate the capability to measure blade-by-blade tip clearances akin to the traditional method.

Abstract 4115642: Resonance Sonomanometry in an Early Prototype Device Effectively Measures Continuous, Noninvasive Blood Pressure

Background: Nearly half of American adults have hypertension; however, reliable, continuous, noninvasive blood pressure (BP) measurement (cNIBP) for inpatient and outpatient use is not currently available. This study evaluated a new method for cNIBP measurement called resonance sonomanometry (RSM). RSM derives blood pressure using first-principles physics, is applicable to any artery, and requires no calibration, blood vessel deformation, or dependence on demographic inputs. Methods: A prospective, observational feasibility study was undertaken to compare carotid artery BP measurements with a prototype ultrasound-based cNIBP device incorporating RSM, to arterial catheter BP measurements in the radial arteries of 60 test subjects. Catheter measurements were obtained from a distal peripheral artery (radial), oscillometric cuff from the brachial artery, and RSM was obtained from a central artery (carotid). This study was the first-in-human study for the RSM method in comparison to arterial catheters. Results: RSM-induced arterial resonance was observed in all tested subjects. For each of the subjects, the arterial resonant frequency increased with increasing BP during systole, and decreased with diastole (consistent with the cardiac cycle), as predicted by the physical model. RSM-derived BP traces were qualitatively similar to catheter data, exhibiting features such as the dicrotic notch. The RSM method yielded similar diastolic BP (DBP), but lower systolic BP (SBP) compared to the arterial catheter, likely due to expected peripheral pulse amplification. RSM DBP was not significantly different from the catheter (+1.5mmHg, p = 0.187), while BP cuff DBP was significantly different from the catheter (−4.3mmHg, p=0.002). There were significant differences in the catheter to RSM SBP (34.1 mmHg, p &lt; 0.01), consistent with the aforementioned expectations from a central-versus-peripheral continuous pressure measurement. Conclusions: RSM is a novel BP measurement technique that could enable cNIBP measurements with accuracy required in hospitals. While the data are promising, significant future work remains. The study was meant to test the RSM method, not the device or form factor. Consequently, the form factor will need to be improved prior to clinical use. The prototype was designed for manual operation; thus, future work will also be needed to enhance the ability of the device to autonomously locate and track the artery for ease of use.

A deep learning based method for left ventricular strain measurements: repeatability and accuracy compared to experienced echocardiographers.

Speckle tracking echocardiography (STE) provides quantification of left ventricular (LV) deformation and is useful in the assessment of LV function. STE is increasingly being used clinically, and every effort to simplify and standardize STE is important. Manual outlining of regions of interest (ROIs) is labor intensive and may influence assessment of strain values. We hypothesized that a deep learning (DL) model, trained on clinical echocardiographic exams, can be combined with a readily available echocardiographic analysis software, to automate strain calculation with comparable fidelity to trained cardiologists. Data consisted of still frame echocardiographic images with cardiologist-defined ROIs from 672 clinical echocardiographic exams from a university hospital outpatient clinic. Exams included patients with ischemic heart disease, heart failure, valvular disease, and conduction abnormalities, and some healthy subjects. An EfficientNetB1-based architecture was employed, and different techniques and properties including data set size, data quality, augmentations, and transfer learning were evaluated. DL predicted ROIs were reintroduced into commercially available echocardiographic analysis software to automatically calculate strain values. DL-automated strain calculations had an average absolute difference of 0.75 (95% CI 0.58-0.92) for global longitudinal strain (GLS), and 1.16 (95% CI 1.03-1.29) for single-projection longitudinal strain (LS), compared to operators. A Bland-Altman plot revealed no obvious bias, though there were fewer outliers in the lower average LS ranges. Techniques and data properties yielded no significant increase/decrease in performance. The study demonstrates that DL-assisted, automated strain measurements are feasible, and provide results within interobserver variation. Employing DL in echocardiographic analyses could further facilitate adoption of STE parameters in clinical practice and research, and improve reproducibility.

Research on ultrasonic synchronous detection method for material residual stress and thickness

Being limited to the different transmission and reception modes and detection signals of the critical refracted longitudinal wave method for stress measurement and the perpendicular incident echo method for thickness measurement, it is necessary to use different probes and equipments when simultaneously measuring stress and thickness. For this difficulty, the acquisition frequency and the number of bits are taken as the research object to realize the optimization of the echo signal. By combining FEM simulations with Comsol software with experimental research, the effects of probe incidence angle, probe spacing, and temperature on ultrasonic waves are investigated, and the relationship between probe spacing and the stress coefficient of measured component (K) is analyzed. A novel ultrasonic synchronous detection method for residual stress and thickness is proposed. This method is based on an integrated transmit-receive probe with oblique incidence, utilizing critical refracted longitudinal wave (LCR wave) for stress detection and synchronously generated transverse waves for thickness measurement. For the first time, a formula for ultrasonic thickness measurement based on inclined incidence is derived. Using self-developed equipment, ultrasonic testing experiments on step test block and cantilever beam loading device were conducted to verify the accuracy and precision of the proposed synchronous detection method for stress and thickness. This method has significant application prospects in the inspection or online monitoring of pressure vessels concerned with fatigue and corrosion performance.

Minimum perceptual time (MPT). Repeatability and reproducibility of variables applied to "sports vision".

"Minimum Perceptual Time" (MPT) is the ability to take the most visual information in the least time. The purpose of the study was to assess intraobserver and interobserver repeatability of a MPT measurement method by using COI-SV® software and to analyze the possible influence of age and sex. MPT was measured in 79 participants by using COI-SV® software. Visual acuity was 20/80 (2.50m) and numbers were gradually increasing in quantity and decreasing in exposure time. The most quantity of numbers and the least time was written down. To assess intraobserver and interobserver repeatability, a protocol based on repeating the test 4 times (2 intrasession and 2 intersessions with 2 examinators) was established. Comparison of means and Spearman correlation were performed to evaluate the influence of sex and age. It was investigated inter and intraexaminer variability using repeatability indices, as well as Bland-Altman analysis to define limits of agreement. A total of 79 participants were included (mean age 32.8 ± 11.95 years, range 19-64 years). Regarding sex, there were no significant differences between men and women (p = 0.080), whereas age and MPT had an inverse correlation (p = 0.01). Interexaminer and intraexaminer repeatability proved to be moderate to good in all methods. Bland-Altman showed difference between sessions was 0.259 ± 2.189 (-4.030 and + 4.549) and difference between examiners was - 0.519 ± 2.104 (-4.642 and + 3.604). MPT measurements with COI-SV® software evidenced moderate to good repeatability and observers` independent result, so it could be included in optometric examinations. WHAT IS KNOWN : Sports optometry is a relatively new field, so research is scarce and of poor quality. The scarcity of literature is practically limited to studies in the field of psychology, although they do not provide us with much information since they have not been studied for the mentioned field. The in-depth study of new standardized measurement methods would be of great help for optometrists in their clinical practice. This study is the first to determine intraobserver and interobserver repeatability and reproducibility for Minimum Perceptual Time (MPT) measurements acquired by the COI-SV® software, exhibiting ICC > 0.7 and establishing limits of agreement by using Bland-Altman analysis. In a significant way, MPT and age would have an inverse correlation, whereas MPT results would be better in men than women. Our results add evidence towards validating the test included in COI-SV® software so that the optometrist can include it in their clinical protocols in order to obtain more complete information on visual examinations.

Quick Spectrometric Characterization of Monolithic Perovskite Silicon Tandem Solar Cells Using Monochromatic Light Sources

In monolithic perovskite silicon dual‐junction solar cells, it is crucial that the subcells are current‐matched to maximize performance. The most precise method to determine the current (mis)match of a monolithic dual‐junction solar cell is a spectrometric measurement with, e.g., a light‐emitting diode (LED)‐based solar simulator. However, recoding multiple current voltage curves (IV curves) under different red‐ and blueshifted spectra relative to the AM1.5g reference spectrum is time‐consuming. Herein, a new method is suggested to quickly test solar cells for current mismatch. A solar simulator with two lasers instead of multiple LEDs is used, so that two monitor diodes can track intensity changes of each light source during the measurement. Postmeasurement corrections can be applied using this data, circumventing long stabilization times of the solar simulator. To minimize the scan time, it is focused only on determining the correct short‐circuit current and not the full IV curve. The measurement method is validated comparing it to conventional spectrometric measurements using a stable III–V monolithic dual‐junction solar cell. The measurement on the proof‐of‐concept setup shows a deviation of only 2.3% in the current at the current matching point compared to the reference measurement.