Statistical Agreement Research Articles

Intercoder Reliability for Use in Qualitative Research and Evaluation

Intercoder reliability can increase trustworthiness, accuracy, rigor, collaboration, and power sharing in qualitative research. Though not every qualitative design can utilize intercoder reliability, this article highlights how positivist qualitative research, community-based participatory research, and participatory evaluation all strengthen when intercoder reliability is sought among coding teams. Basic calculations for intercoder reliability can be completed manually or with software, making it an accessible metric to inform counseling research and evaluation, benefitting counselor education and practice. Interpreting metrics like percent agreement or kappa statistic largely depends on data context and potential impact of the study, which warrants researchers and evaluators to assess and understand the consequences of their work. Using ICR with clinical data such as interviews and other qualitative sources can be utilized to teach trainees the method in counseling research and evaluation and help make visible the important contributions of qualitative research using collaborative teams in counselor education.

Feasibility of OpenPose markerless motion analysis in a real athletics competition.

This study tested the performance of OpenPose on footage collected by two cameras at 200 Hz from a real-life competitive setting by comparing it with manually analyzed data in SIMI motion. The same take-off recording from the men's Long Jump finals at the 2017 World Athletics Championships was used for both approaches (markerless and manual) to reconstruct the 3D coordinates from each of the camera's 2D coordinates. Joint angle and Centre of Mass (COM) variables during the final step and take-off phase of the jump were determined. Coefficients of Multiple Determinations (CMD) for joint angle waveforms showed large variation between athletes with the knee angle values typically being higher (take-off leg: 0.727 ± 0.242; swing leg: 0.729 ± 0.190) than those for hip (take-off leg: 0.388 ± 0.193; swing leg: 0.370 ± 0.227) and ankle angle (take-off leg: 0.247 ± 0.172; swing leg: 0.155 ± 0.228). COM data also showed considerable variation between athletes and parameters, with position (0.600 ± 0.322) and projection angle (0.658 ± 0.273) waveforms generally showing better agreement than COM velocity (0.217 ± 0.241). Agreement for discrete data was generally poor with high random error for joint kinematics and COM parameters at take-off and an average ICC across variables of 0.17. The poor agreement statistics and a range of unrealistic values returned by the pose estimation underline that OpenPose is not suitable for in-competition performance analysis in events such as the long jump, something that manual analysis still achieves with high levels of accuracy and reliability.

Determination of promethazine in forensic samples using multi-walled carbon nanotube-gold nanoparticle electrochemical sensor.

An electrochemical sensor was developed based on a glassy carbon electrode (GCE) modified with multi-walled carbon nanotubes (MWCNTs) and gold nanoparticles (AuNPs) for the determination of promethazine (PMZ) in 'purple drank', pharmaceutical formulations, and synthetic saliva. The oxidation of PMZ at the modified electrode occurred at a higher cathodic potential and produced a higher sensitivity compared to the unmodified GCE. The morphology of the modified electrode was characterized using field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). The presence of MWCNTs and AuNPs was confirmed. The optimized parameters included the concentration and pH of the supporting electrolyte, amount of modifiers used to fabricate the electrode, deposition potential, and time. Using these optimized conditions, the method has a linear range from 0.5 to 100 μmol L-1, with a R2 value of 0.9991. The limit of detection (3SDblank/slope) was 0.13 μmol L-1. The proposed electrochemical sensor was successfully applied for the determination of PMZ in 'purple drank', pharmaceutical formulations, and spiked synthetic saliva samples. The results obtained from this sensor were in statistical agreement with the values obtained using the reference gas chromatography-flame ionization method.

Experimental study on flow boiling of HFE-7100 in rectangular parallel microchannel

With the rapid development of microelectronic technology, the integration and power of chip are increasing. Heat dissipation with high heat flux in limited space has become a bottleneck restricting the efficient and stable operation of the microelectronic devices. Flow boiling in microchannel heat sink is one of the most essential candidates for solving this problem. It has been shown that remarkable high heat transfer performance can be achieved through the liquid-to-vapor change process, which can dissipate a large amount of heat from a small area. In addition, dielectric fluorinated fluids, such as HFE-7100, HFE-7200, and FC-72, are especially suitable for cooling microelectronic devices, because of their excellent safety and environmental characteristics. However, dielectric fluorinated fluids have poorer thermophysical properties than water. Thus, the flow boiling heat transfer characteristics of dielectric fluorinated fluids can be different from those of water. In this work, flow boiling heat transfer and flow characteristics of HFE-7100 in a rectangular parallel microchannel are investigated. The tests are conducted at mass fluxes from 88.9 to 277.8 kg·m<sup>–2</sup>·s<sup>–1</sup>, inlet subcooling temperature from 20.5 to 35.5 ℃ and effective heat flux from 12 to 279 kW·m<sup>–2</sup> at nearly atmospheric pressure. The effects of mass flux, inlet subcooling temperature, effective heat flux and vapor quality are examined and analyzed. Additionally, flow visualization is also obtained to explain the heat transfer mechanism during the experiments. The results show that the boiling hysteresis is observed for HFE-7100 at low inlet subcooling temperature, and the increasing inlet subcooling temperature and mass flux can delay the onset of nucleate boiling. The increases of inlet subcooling temperature and mass flux can enhance the two-phase heat transfer coefficient. And the two-phase heat transfer coefficient is significantly dependent on the inlet subcooling temperature in the slug flow, while it is significantly dependent on the mass flux in the annular flow. The two-phase pressure drop increases drastically as the effective heat flux increases. And the two-phase pressure drops with different mass fluxes at constant vapor quality are obviously different between the slug flow and the annular flow. Furthermore, the experimental data are compared with four predicted values of the literature. It is found that the correlation of Lockhart has the best statistical agreement with an MAE of 19.6% and over 85% of points in the deviation bandwidth of ±30%. The results in this paper give valuable theoretical guidance for designing and optimizing heat dissipation equipment for microelectronic devices. By utilizing HFE-7100 as the coolant and microchannel heat sinks in flow boiling, it is possible to enhance the stability and reliability of the electronic devices. Additionally, the heat transfer performance associated with different heat fluxes can be improved by regulating the inlet subcooling and mass flow rate. Finally, the two-phase pressure drop correlation proposed by Lockhart can be employed to predict the pump power for heat dissipation equipment.

CuticleTrace: A toolkit for capturing cell outlines from leaf cuticle with implications for paleoecology and paleoclimatology.

Leaf epidermal cell morphology is closely tied to the evolutionary history of plants and their growth environments and is therefore of interest to many plant biologists. However, cell measurement can be time consuming and restrictive with current methods. CuticleTrace is a suite of Fiji and R-based functions that streamlines and automates the segmentation and measurement of epidermal pavement cells across a wide range of cell morphologies and image qualities. We evaluated CuticleTrace-generated measurements against those from alternate automated methods and expert and undergraduate hand tracings across a taxonomically diverse 50-image data set of variable image qualities. We observed ~93% statistical agreement between CuticleTrace and expert hand-traced measurements, outperforming alternate methods. CuticleTrace is a broadly applicable, modular, and customizable tool that integrates data visualization and cell shape measurement with image segmentation, lowering the barrier to high-throughput studies of epidermal morphology by vastly decreasing the labor investment required to generate high-quality cell shape data sets.

Clinical research of fibroscan ‒ TE-CAP at noninvasive diagnosis of hepatic steatosis in children

Background & aimsThe authors assess the diagnostic accuracy of the Transient Elastography-Controlled Attenuation Parameter (TE-CAP) in children of Southern China. Methods105 obese or overweight children and adolescents were enrolled in the diagnostic test of TE-CAP assessment of hepatic steatosis using MRI-PDFF. Hepatic steatosis grades S0-S3 were classified. Statistical correlation, agreement and consistency between methods were evaluated. The diagnostic efficiency of TE-CAP was evaluated. The authors used the cutoff value of TE-CAP to detect hepatic steatosis in another 356 children. ResultsThe Area Under Curve (AUC) of TE-CAP for grade ≥ S1, ≥ S2, and ≥ S3 steatosis were 0.975, 0.984, and 0.997, respectively. For detecting ≥ S1 steatosis, TE-CAP had a sensitivity of 96 % and a specificity of 97 %. For detecting ≥ S2 steatosis, TE-CAP had a sensitivity of 97 % and a specificity of 93 %. For detecting ≥ S3 steatosis, TE-CAP had a sensitivity of 1 and a specificity of 94 %. TE-CAP and MRI-PDFF had a linear correlation (r = 0. 0.87, p < 0.001). The hepatic steatosis was identified in 40.2 % (143/356) of children in which the obesity and overweight were 69.8 % (113/162) and 40.0 % (18/45). ConclusionTE-CAP showed excellent diagnostic accuracy in pediatric hepatic steatosis.

NÍVEIS DE EVIDÊNCIA EM ESTUDOS ONCOLÓGICO-ORTOPÉDICOS - ACTA ORTOP BRAS (1993-2022)

ABSTRACT Objectives: to identify oncological-orthopedic studies published in Acta Ortopédica Brasileira over three decades; to classify them according to the type and level of evidence (LE); to observe the inter-rater agreement in the classification of studies; to analyze the studies retrospectively, according to levels of evidence; and to outline the evolution of the evidence in the study period. Methods: Descriptive analyses were performed with absolute and relative frequencies of studies published between 1993 and 2022. Inter-rater agreement was analyzed by percentage of agreement and Kappa statistic (95%CI). The interpretation of the magnitude of the agreement was performed according to Landis &amp; Koch. The association between classifications and publication period was analyzed using Fisher’s exact test. The analyses were performed using the R program (significance of 5%). Results: 69/1349 papers were selected; there was a significant association between type of study, statistical methodology, and LE with publication period (p &lt; 0.05); inter-rater agreement regarding LE was 92.8%. Conclusions: Oncological-orthopedic studies accounted for 5.1% of all published papers. Regarding the LE, 80% were NE IV and V studies, despite the evolution observed between the first and last decade (decrease in LE V studies and increase in LE II, III and IV). Level of Evidence III, Retrospective Comparative Study.

Reprodutibilidade de instrumento para avaliação motora de jovens com autismo

Abstract Introduction Individuals with autistic spectrum disorder (ASD) have motor impairments that precede communi-cation and socialization disorders. Evaluative instruments compatible with the real possibilities and specificities of patients with ASD, and who quantitatively and qualitatively translate the data in which is wished to intervene with therapeutic actions, are important both in the scope of research and in the clinical evaluation of physiotherapists. Objective To test the interobserver and intraobserver reproducibility of the instrument “Gross Motor Assessment of Children and Adolescents with Autism Spectrum Disorder” (GMA-AUT checklist). Methods The sample consisted of 34 individuals with ASD, aged between 6 and 18 years. The interobserver reproducibility was performed in a blinded manner by two physiotherapists experts in the ASD area of treatment. Intraobserver reproducibility was performed by one of the evaluators on two different days, with a gap of seven days and without access to data from the first evaluation. To verify the reproducibility, percentage of agreement and kappa statistics (k) were used, with the weighted kappa and, for the instrument scores, the intraclass correlation coefficient (ICC). Results The GMA-AUT checklist showed excellent intraobserver agreement, with k ≥ 0.75 and ICC &gt; 0.75. Interobserver reproducibility ranged from good to sufficient agreement with k between 0.40 and 0.75 and ICC &gt; 0.75 for the most part. Conclusion The GMA-AUT checklist had excellent intraobserver reproducibility and, therefore, can be reliably used for assessments of individuals aged between 6 and 18 years with ASD.

External validation of the Brain Tumour Reporting and Data System (BT-RADS) in the multidisciplinary managementof post-treatment gliomas.

To independently and externally validate the Brain Tumour Reporting and Data System (BT-RADS) for post-treatment gliomas and assess interobserver variability. In this retrospective observational study, consecutive MRIs of 100 post-treatment glioma patients were reviewed by two independent radiologists (RD1 and RD2) and assigned a BT-RADS score. Inter-observer agreement statistics were determined by kappa statistics. The BT-RADS-linked management recommendations per score were compared with the multidisciplinary meeting (MDM) decisions. The overall agreement rate between RD1 and RD2 was 62.7% (κ = 0.67). The agreement rate between RD1 and consensus was 83.3% (κ = 0.85), while the agreement between RD2 and consensus was 69.3% (κ = 0.79). Among the radiologists, agreement was highest for score 2 and lowest for score 3b. There was a 97.9% agreement between BT-RADS-linked management recommendations and MDM decisions. BT-RADS scoring led to improved consistency, and standardised language in the structured MRI reporting of post-treatment brain tumours. It demonstrated good overall agreement among the reporting radiologists at both extremes; however, variation rates increased in the middle part of the spectrum. The interpretation categories linked to management decisions showed a near-perfect match with MDM decisions.

Measurement of sucrose concentration using Imbibition length on paper: A device for equipment-free and environmentally-friendly detection

The Lucas-Washburn equation is commonly used to predict the distance (L) that a liquid travels through paper. This equation establishes that L2 is linear with time and inversely proportional to the viscosity of the liquid. However, there is currently no theoretical equation connecting the viscosity of a solution to its concentration. In this study, the imbibition flow of a sucrose solution was measured along the length of a horizontal strip of filter paper, featuring a printed, thermometer-shaped hydrophobic boundary. A sample (38 μL) was dispensed onto the bulb area, and the solution's flow was visually tracked using a red dye added to the sample. The imbibition length (L) was measured by a vernier caliper at 10.0 min after the sample addition. An empirical equation, based on literature values of the viscosity (η) and concentration (C) of sucrose solutions, was proposed. By integrating this empirical equation with the Lucas-Washburn equation, the following equation was derived: L = a⋅exp{-(bC + cC2)}, where ‘a’, ‘b’ and ‘c’ are parameters. This equation was fitted to the dataset of L and C, covering C values from 0 to 60 % w/w standard sucrose solutions, resulting in a coefficient of determination of 0.9987. The plot of L against C was observed to closely follow a linear line, with a fitting providing a coefficient of determination of 0.9986. The sucrose contents in samples, such as soft drinks, syrups, and sugarcanes, determined using the imbibition length method and conventional refractometry, were in statistical agreement via the paired t-test at the 95 % confidence level. This method is simple, instrument-free, requiring only a small amount of safe red food dye, and can be conducted on-site.

ALL-CAUSE MORTALITY AND CAUSE OF DEATH IN US LONG-LIVED SIBLINGS: DATA FROM THE LONG LIFE FAMILY STUDY

Abstract This study compared the mortality risk of long-lived siblings with the general population in the US and investigated the leading causes of death and the correspondence in age at death and causes of death between long-lived siblings. In the Long Life Family Study (LLFS), 1,264 siblings (Mean age 90.1, SD 6.4) were recruited from the US and followed over 12 years. Their survival function, based on the Kaplan-Meier estimator, was compared with an age-, race-, and sex-matched sample from US census data. To examine underlying and contributing causes, we examined in detail 338 deaths with complete death adjudication using death certificates, family interview, hospital and nursing home records at the Pittsburgh field center through the year 2018. Concordance between siblings was examined using correlation coefficients, Bland-Altman plots, percent agreement, and Kappa statistics. The LLFS proband siblings had better survival compared with US general population matched on birth cohort and age at enrollment. Age at death ranged from 75-104, mean 91.4 (SD 4.8). The leading causes of death were cardiovascular disease (33.1%), dementia (22.2%), and cancer (10.7%). In addition, we did not find significant correspondence in the age at death, the underlying cause of death, or conditions directly contributing to death between siblings. Our findings demonstrate further exceptional longevity in the LLFS proband generation compared to the general population, but do not show significant correspondence in age at death and causes of death between siblings.

Comparison of the Automated OvaCyte Telenostic Faecal Analyser versus the McMaster and Mini-FLOTAC Techniques in the Estimation of Helminth Faecal Egg Counts in Equine.

Gastrointestinal helminth parasites continue to be a significant threat to the health of equine. OvaCyte Telenostic (OCT) (Telenostic Ltd., Kilkenny, Ireland) has developed an automated digital microscope utilising Artificial Intelligence to identify and count the clinically important helminth species in equine, bovine, and ovine host species. In this paper, the performance of the OCT analyser was evaluated for the detection and counting of equine helminth species parasites and its performance compared to the currently accepted benchmark methods of faecal egg counts being the McMaster and the Mini-FLOTAC techniques. A pairwise comparison of tests was assessed based on the correlation of egg counts and Cohen's kappa agreement statistics for dichotomized outcomes. Bayesian latent class analysis was used to estimate the sensitivity and specificity of all three techniques in the absence of a gold standard for four helminth parasites (strongyles, Anoplocephala spp., Parascaris spp. and Strongyloides westeri). Based on the analysis of 783 equine faecal samples, we found a high level (ρ ≥ 0.94) of correlation between each pairwise comparison of techniques for strongyle egg counts. Cohen's kappa agreement between techniques was high for strongyles and S. westeri, moderate for Parascaris spp., and low for Anoplocephala spp. All three techniques had a high sensitivity and specificity (>0.90) for strongyles. Across helminth parasites, the sensitivity of the OCT was the highest of the three techniques evaluated for strongyles (0.98 v 0.96 and 0.94), Anoplocephala spp. (0.86 v 0.44 and 0.46) and Parascaris spp. (0.96 v 0.83 and 0.96); but lowest for S. westeri (0.74 v 0.88 and 0.88), compared to McMaster and Mini-FLOTAC, respectively. In terms of specificity, OCT was the lowest in two species (Parascaris spp. 0.96, Anoplocephala spp. 0.95). In conclusion, OCT has a sensitivity and specificity statistically similar to both McMaster and Mini-FLOTAC, and had a higher correlation with Mini-FLOTAC. The OCT point of care faecal analyser offers improved workflow, test turn-around time and does not require trained laboratory personnel to operate or interpret the results.

Enhanced sleep staging with artificial intelligence: a validation study of new software for sleep scoring.

Manual sleep staging (MSS) using polysomnography is a time-consuming task, requires significant training, and can lead to significant variability among scorers. STAGER is a software program based on machine learning algorithms that has been developed by Medibio Limited (Savage, MN, USA) to perform automatic sleep staging using only EEG signals from polysomnography. This study aimed to extensively investigate its agreement with MSS performed during clinical practice and by three additional expert sleep technicians. Forty consecutive polysomnographic recordings of patients referred to three US sleep clinics for sleep evaluation were retrospectively collected and analyzed. Three experienced technicians independently staged the recording using the electroencephalography, electromyography, and electrooculography signals according to the American Academy of Sleep Medicine guidelines. The staging initially performed during clinical practice was also considered. Several agreement statistics between the automatic sleep staging (ASS) and MSS, among the different MSSs, and their differences were calculated. Bootstrap resampling was used to calculate 95% confidence intervals and the statistical significance of the differences. STAGER's ASS was most comparable with, or statistically significantly better than the MSS, except for a partial reduction in the positive percent agreement in the wake stage. These promising results indicate that STAGER software can perform ASS of inpatient polysomnographic recordings accurately in comparison with MSS.

Evaluation of Bleeding Self-Assessments By Patients with Immune Thrombocytopenia (ITP): An Agreement Study

Introduction. Immune thrombocytopenia (ITP) is an autoimmune condition that causes an increase in the risk of bleeding. Bleeding is a patient-important outcome; however, timely and complete assessments of bleeding are time- and labour-intensive. ITP bleeding measurements may be simplified with patient self-assessments. We designed this study to compare the agreement of bleeding assessments done by ITP patients and by trained research staff. Methods. All patients were identified from the McMaster ITP Registry, a longitudinal registry study of consecutive adult patients with thrombocytopenia followed at the McMaster University Medical Centre, a tertiary referral clinic. A modified version of the ITP Bleeding Scale was used for all bleeding assessments, which captured the patients' worst bleeding event at each of 9 anatomical sites - skin, mouth, epistaxis, gastrointestinal, genitourinary, gynecological, pulmonary, ocular or intracranial - graded from 0 (no bleeding) to 2 (severe bleeding) from the time of the last assessment (typically 6 months prior). Patients were provided with instructions on how to use the scale and asked to complete bleeding self-assessments using an online tool. Once the patients completed their self-assessments, a trained research staff member contacted the patient to repeat the bleeding assessment by telephone. Chance-corrected interrater agreement was determined using the kappa statistic for 2-way agreement (Grade 2 vs. Grade 0 or 1 bleeding) and for 3-way agreement (Grade 0 vs. Grade 1 vs. Grade 2). Chance-independent 2-way agreement was also measured using the phi statistic. The primary analysis was the 2-way kappa, since the detection of Grade 2 bleeds is clinically important. Results. We enrolled 108 consecutive patients with ITP from the McMaster ITP Registry who had duplicate bleeding assessments done. The median time between assessments was 3 days (IQR, 2-5). Median age of patients in the study was 53 years (IQR, 38-64), 64% were female. The worst bleeding events, as determined by research staff, were Grade 0 (n=22, 20.4%), Grade 1 (n=34, 31.5%) or Grade 2 (n=52, 48.1%). There was perfect agreement for bleeding assessments at all anatomical sites for 44 patients (40.7%). There were no intracranial hemorrhages and no Grade 2 genitourinary or pulmonary bleeds were reported. Chance-corrected 2-way agreement was excellent for gynecological (k=0.86, 95% CI 0.71-1.02), gastrointestinal (k=1), genitourinary (k=1), pulmonary (k=1) and intracranial (k=1) bleeds ( Table). Agreement was good for skin (k=0.68, 95% CI, 0.54-0.82), oral (k=0.76, 95% CI, 0.53-0.98) and ocular (k=0.66, 95% CI, 0.04-1.28) bleeds, and moderate for epistaxis (k=0.58, 95% CI, 0.21-0.95). Results of chance-independent agreement and 3-way agreement were similar. Conclusions. Bleeding self-assessments by ITP patients yielded comparable results to trained research staff. Agreement for skin and epistaxis was lower than for other sites, suggesting that additional instructions or prompts may be needed for these categories. Bleeding self-assessments could simplify data collection in research and in clinical practice.

Reconstructing temperature fields from OH distribution and soot volume fraction in turbulent flames using an artificial neural network

We present a methodology based on artificial neural networks for reconstructing flame temperature fields from planar distributions of hydroxyl (OH) radicals and soot volume fraction in turbulent jet flames. A convolutional neural network was trained using planar images of flame temperature, soot volume fraction and OH simultaneously recorded with laser-based experimental methods. Then, the capacity and accuracy of the neural network on reconstructing flame temperatures were assessed for the flame conditions not only within the training domain but also out of it. The results showed that the supervised neural network can reconstruct instantaneous temperature fields to within ± 60 K for the flame conditions within the training domain, and to within ± 150 K for the flame conditions outside of the training domain. Probability density functions (PDF) of reconstructed temperature and the joint PDFs with OH signals and soot volume fractions also show good statistical agreement with experiments. This work has application in extending measurement techniques into regimes that are presently difficult to achieve, such as by obtaining the training data for temperature with established low-speed imaging methods and using the neural network method to predict temperature from high-speed imaging of the other two scalars.

Quantitative analysis of chest computed tomography of COVID-19 pneumonia using a software widely used in Japan.

This study aimed to determine the optimal conditions to measure the percentage of the area considered as pneumonia (pneumonia volume ratio [PVR]) and the computed tomography (CT) score due to coronavirus disease 2019 (COVID-19) using the Ziostation2 image analysis software (Z2; Ziosoft, Tokyo, Japan), which is popular in Japan, and to evaluate its usefulness for assessing the clinical severity. We included 53 patients (41 men and 12 women, mean age: 61.3 years) diagnosed with COVID-19 using polymerase chain reaction who had undergone chest CT and were hospitalized between January 2020 and January 2021. Based on the COVID-19 infection severity, the patients were classified as mild (n = 38) or severe (n = 15). For 10 randomly selected samples, the PVR and CT scores by Z2 under different conditions and the visual simple PVR and CT scores were compared. The conditions with the highest statistical agreement were determined. The usefulness of the clinical severity assessment based on the PVR and CT scores using Z2 under the determined conditions was statistically evaluated. The best agreement with the visual measurement was achieved by the Z2 measurement condition of ≥-600 HU. The areas under the receiver operating characteristic curves, Youden's index, and the sensitivity, specificity, and p-values of the PVR and CT scores by Z2 were as follows: PVR: 0.881, 18.69, 66.7, 94.7, and <0.001; CT score: 0.77, 7.5, 40, 74, and 0.002, respectively. We determined the optimal condition for assessing the PVR of COVID-19 pneumonia using Z2 and demonstrated that the AUC of the PVR was higher than that of CT scores in the assessment of clinical severity. The introduction of new technologies is time-consuming and expensive; our method has high clinical utility and can be promptly used in any facility where Z2 has been introduced.

Evaluation of Agreement Between Sweep Visual Evoked Potential Testing and Subjective Visual Acuity.

The primary objective of this study was to evaluate the agreement of visual acuity (VA) obtained with the sweep visual evoked potential (sVEP) method with the VA obtained with the Snellen chart. The secondary objective was to examine the effect of age and gender on agreement. Best corrected VAs of subjects were recorded with the Snellen chart, and sVEP testing was performed according to the recommendations of the International Society for Clinical Electrophysiology of Vision (ISCEV). Snellen VAs and sVEP measurements were analyzed using logMAR conversion for statistical analysis. Agreement was evaluated with Bland-Altman analysis. The study included 49 subjects with a mean age of 53.5±17.3 years (range: 19-75 years) and mean Snellen VA of 0.31±0.32 logMAR (range: 1.3-0.0 logMAR). In the Bland-Altman analysis, the mean differences between the VA and sVEP measurements (VA-sVEP) were significantly different and outside the limits of agreement (p=0.035). A significant proportional bias (p=0.0007) was found in the regression analysis performed between VA-sVEP and the mean VA. According to the Bland-Altman analysis of sex subgroups, there was a significant difference between VA and sVEP measurements in female subjects (p=0.006). The difference between VA and sVEP measurement increased significantly with older age (R2: 0.306, p<0.001, β: 0.05 [0.03, 0.08]). In conclusion, sVEP measurements and VAs did not show statistical agreement. Cranial anatomy and endocrine differences of the subjects may affect their sVEP measurements. The difference between the methods varies according to VA level. Directly using sVEP results instead of VA would not be appropriate.

Underlying mathematical relations for efficient COMET response expansion coefficient and core calculations

The coarse mesh transport code COMET, a hybrid stochastic-deterministic neutronics solver with formidable computation speed, can provide high fidelity transport solutions to various reactor core problems. In this paper, to take advantage of local rotational and reflection symmetry existing in many reactor cores (e.g., fuel lattices and reflector blocks), the underlying mathematical relations among the response expansion coefficients of symmetric coarse meshes are developed to further improve the computational efficiency in both COMET response expansion coefficient generation and core calculation. This is done by a rigorous derivation of the transformation matrices for the angular and spatial expansion moments resulting from a rotation of a coarse mesh by an arbitrary angle or reflection of a coarse mesh. As a result, the relations for the response expansion coefficients of a coarse mesh with rotational symmetry can be then written as the Kronecker product of those transformation matrices. For coarse meshes with reflection symmetry, the sparse property, the outgoing surface symmetry property and the incident surface symmetry property of response expansion coefficients are rigorously derived. These underlying mathematical relations are implemented into COMET and evaluated on three stylized 3D PWR whole core benchmark problems. The COMET results using the response expansion coefficient library based on the underlying mathematical relations were compared to those using the library directly generated by Monte Carlo for all surfaces. It was found that the eigenvalues as well as the pin and assembly fission densities using the two libraries are in statistical agreement as expected. This indicates that the new COMET using the underlying mathematical relations maintains the high fidelity of the original COMET while improving computational efficiency by 10.7 and 3.7 times for COMET response expansion coefficient generation and core calculation, respectively. This also reduces the size of the library by 10.7 times.

Metabarcoding using nanopore long-read sequencing for the unbiased characterization of apicomplexan haemoparasites.

Apicomplexan haemoparasites generate significant morbidity and mortality in humans and other animals, particularly in many low-to-middle income countries. Malaria caused by Plasmodium remains responsible for some of the highest numbers of annual deaths of any human pathogen, whilst piroplasmids, such as Babesia and Theileria can have immense negative economic effects through livestock loss. Diagnosing haemoparasites via traditional methods like microscopy is challenging due to low-level and transient parasitaemia. PCR-based diagnostics overcome these limitations by being both highly sensitive and specific, but they may be unable to accurately detect coinfections or identify novel species. In contrast, next-generation sequencing (NGS)-based methods can characterize all pathogens from a group of interest concurrently, although, the short-read platforms previously used have been limited in the taxonomic resolution achievable. Here, we used Oxford Nanopore Technologies' (ONT) long-read MinION™ sequencer to conduct apicomplexan haemoparasite metabarcoding via sequencing the near full-length 18S ribosomal RNA gene, demonstrating its ability to detect Babesia, Hepatozoon, Neospora, Plasmodium, Theileria and Toxoplasma species. This method was tested on blood-extracted DNA from 100 dogs and the results benchmarked against qPCR and Illumina-based metabarcoding. For two common haemoparasites, nanopore sequencing performed as well as qPCR (kappa agreement statistics > 0.98), whilst also detecting one pathogen, Hepatozoon felis, missed by the other techniques. The long-reads obtained by nanopore sequencing provide an improved species-level taxonomic resolution whilst the method's broad applicability mean it can be used to explore apicomplexan communities from diverse mammalian hosts, on a portable sequencer that easily permits adaptation to field use.

Validation of D–T fusion power prediction capability against 2021 JET D–T experiments

JET experiments using the fuel mixture envisaged for fusion power plants, deuterium and tritium (D–T), provide a unique opportunity to validate existing D–T fusion power prediction capabilities in support of future device design and operation preparation. The 2021 JET D–T experimental campaign has achieved D–T fusion powers sustained over 5 s in ITER-relevant conditions i.e. operation with the baseline or hybrid scenario in the full metallic wall. In preparation of the 2021 JET D–T experimental campaign, extensive D–T predictive modelling was carried out with several assumptions based on D discharges. To improve the validity of ITER D–T predictive modelling in the future, it is important to use the input data measured from 2021 JET D–T discharges in the present core predictive modelling, and to specify the accuracy of the D–T fusion power prediction in comparison with the experiments. This paper reports on the validation of the core integrated modelling with TRANSP, JINTRAC, and ETS coupled with a quasilinear turbulent transport model (Trapped Gyro Landau Fluid or QualLiKiz) against the measured data in 2021 JET D–T discharges. Detailed simulation settings and the heating and transport models used are described. The D–T fusion power calculated with the interpretive TRANSP runs for 38 D–T discharges (12 baseline and 26 hybrid discharges) reproduced the measured values within 20. This indicates the additional uncertainties, that could result from the measurement error bars in kinetic profiles, impurity contents and neutron rates, and also from the beam-thermal fusion reaction modelling, are less than in total. The good statistical agreement confirms that we have the capability to accurately calculate the D–T fusion power if correct kinetic profiles are predicted, and indicates that any larger deviation of the D–T fusion power prediction from the measured fusion power could be attributed to the deviation of the predicted kinetic profiles from the measured kinetic profiles in these plasma scenarios. Without any posterior adjustment of the simulation settings, the ratio of predicted D–T fusion power to the measured fusion power was found as 65%–96% for the D–T baseline and 81%–97% for D–T hybrid discharge. Possible reasons for the lower D–T prediction are discussed and future works to improve the fusion power prediction capability are suggested. The D–T predictive modelling results have also been compared to the predictive modelling of the counterpart D discharges, where the key engineering parameters are similar. Features in the predicted kinetic profiles of D–T discharges such as underprediction of ne are also found in the prediction results of the counterpart D discharges, and it leads to similar levels of the normalized neutron rate prediction between the modelling results of D–T and the counterpart D discharges. This implies that the credibility of D–T fusion power prediction could be a priori estimated by the prediction quality of the preparatory D discharges, which will be attempted before actual D–T experiments.