Conventional Measurements Research Articles

Estimation of Physico-Chemical Properties of Soil Using Machine Learning

This study leverages soil images to determine its physico-chemical characteristics from two locations in Benue State, North-Central Nigeria: Vandeikya (7.099653°, 8.572102°) and Konshisha (6.783539°, 9.069549°). Practical alternatives to traditional soil quality estimation methods, often costly and inaccessible in resource-poor regions, were implemented. The study integrates Machine Learning (ML) and Deep Learning (DL) techniques with soil image analysis, employing image feature extraction through Gray-Level Co-occurrence Matrix (GLCM) and Gabor filters to enhance the feature space across 1,388 samples (each consisting of 600g of soil) and 16 properties. We evaluated different models, including Support Vector Regression (SVR), a Convolutional Neural Network (CNN), an optimized CNN using Grid Search, and a stacked ML-CNN approach. The models were assessed on their ability to predict soil properties while minimizing error rates. The SVR model showed limited predictive performance, with its best results yielding slightly over 40% R² and negative scores for physical properties. The CNN model performed better but had feature scores below 80% R². The optimized CNN model surpassed 90% R² and reduced MAE by more than 50% for several properties. The stacked ML-CNN model further improved these metrics, demonstrating the effectiveness of the integrated approach. This research highlights the potential for using machine learning and image-based analysis as a scalable, cost-effective alternative to conventional soil testing, offering practical solutions for regions where conventional measurement tools are scarce. Integration with historical soil data might also open new possibilities for enhancing the accuracy and applicability of these methods for broader soil management practices.

A Study on the Analysis of Reduction Effects and Comparison of Economic Feasibility by Applying the LID Technique

This study conducted a comparative review of the effects and project costs of four different flood runoff reduction measures applied in the Dongnam District 1 watershed. Using the XP-SWMM model, the effects of three LID (low-impact development) technologies—infiltration trenches, permeable pavement, and green roofs—were analyzed. The results showed reductions in both peak flood discharge (32.65 m3/s → 27.85 m3/s) and total runoff volume (99,725 m3 → 86,814 m3). However, the application of LID technologies alone is insufficient for mitigating flood risks. Therefore, flood reduction measures were categorized into four CASEs, combining LID technologies with conventional stormwater management facilities. The cost comparison for each CASE was as follows: CASE 1 (LID + pump) at 22.3 billion KRW, CASE 2 (LID + stormwater storage facility) at 20.3 billion KRW, CASE 3 (pump) at 20.6 billion KRW, and CASE 4 (stormwater storage facility) at 21.0 billion KRW. Despite the use of LID technologies, the project costs for CASEs 3 and 4, which utilized existing reduction methods, were higher. This indicates that integrating LID technologies with conventional reduction measures is likely the most effective approach.

Differences in metabolic syndrome severity and prevalence across nine waist circumference measurements collected from smartphone digital anthropometrics

Background & AimsGiven the technological advances in 3D smartphone (SP) anthropometry, this technique presents a unique opportunity to improve metabolic syndrome (MetS) screening through optimal waist circumference (WC) landmarking procedures. Thus, the purpose of this study was to evaluate the associations between individual MetS risk factors and nine independent WC sites collected using tape measurement or SP anthropometrics and to determine the differences in MetS severity and prevalence when using these different WC measurement locations. MethodsA total of 130 participants (F:74, M:56; age: 27.8±11.1) completed this cross-sectional evaluation. Using traditional tape measurement, WC was measured at the lowest rib (WCRib), iliac crest (WCIliac), and between the WCRib and WCIliac (WCMid). Additionally, WC measurements were automated using a SP application at six sites along the torso. MetS risk factors were used to calculate MetS severity (MetSindex) and prevalence. Associations were evaluated using multiple linear regression, the effect of each WC site on MetSindex was analyzed using mixed-models ANCOVA, and differences in MetS prevalence using WCIliac as the current standard were determined using sensitivity, specificity, and Chi-squared and odds ratios. ResultsThe reference SP-WC (SPRef) and WCRib demonstrated the largest associations (all p < 0.001) with HDL cholesterol (SPRef: -0.48; WCRib: -0.49), systolic (SPRef: 0.32; WCRib: 0.30) and diastolic blood pressure (SPRef: 0.34; WCRib: 0.32), and fasting blood glucose (SPRef: 0.38; WCRib: 0.37). SPRef and WCRib were the only WC without significantly different MetSindex; yet demonstrated lower MetSindex and sensitivity (SPRef: 77.8%; WCRib: 74.1%) relative to WCIliac, the conventional (or standard) WC measure. ConclusionsCompared to the current standard, SPRef and WCRib protocols are more highly associated with individual MetS risk factors and produce different MetSindex and diagnoses; highlighting the need for new MetS WC protocols. Given the surge in remote/mobile healthcare, SPRef may be an alternative to traditional methods in this context but requires further investigation before implementation.

NAVIGATING THE REGULATORY LANDSCAPE OF VOLUNTARY SUSTAINABILITY STANDARDS IN INTERNATIONAL FOOD TRADE: A MULTILATERAL INTERPLAY - DOI: 10.12818/P.0304-2340.2024v85p171

Voluntary sustainability standards (VSSs) are non-mandatory criteria designed to foster sustainable practices throughout the global supply chain. These standards are particularly prevalent in the agri-food sector, where they aim to support wider public policy objectives such as sustainable food production, animal welfare, healthy lifestyle, and labour conditions. Significant challenges arises from the fact that VSSs, despite their voluntary nature, they often impose mandatory effect in the global supply chain. They also often lack easily-identifiable features of the product themselves. These creates systematic problems for the global food trade system, where conventional regulation address governmental measures on goods with specific inherent characteristics that can be clearly identified in the final product. This article explored the interrelationship among private VSSs, national regulations and international treaties within the agri-food industry. It highlights ambiguity surrounding the regulatory framework for VSSs under the WTO law, noting the absence of a consensus on how relevant provisions should be interpreted. Despite the diversity among various VSSs, VSSs, this article argues for the potential for harmonization and equivalence among VSSs. By aligning various VSSs and with technical regulations, it is possible to strike a balance between trade liberalization and promotion of sustainable practices.

Robust approximation of the conditional mean for applications of Machine Learning

Machine Learning approaches are increasingly used in a range of applications. They are shown to produce low conventional errors but in many real applications fail to model the underlying input–output relationships. This is because the error measures used only predict the conditional mean under some restrictive assumptions, often not met by the data we extract from applications. However, new approaches to Machine Learning, for example using Evolutionary Computation, allow a range of alternative error measures to be used. This paper explores the use of the Fit to Median Error measure in machine learning regression automation, using evolutionary computation in order to improve the approximation of the ground truth. When used alongside conventional error measures it improves the robustness of the learnt input–output relationships to the conditional median. It is compared to traditional regularisers to illustrate that the use of the Fit to Median Error produces regression neural networks which model more consistent input–output relationships. The problem considered is ship power prediction using a fuel-saving air lubrication system, which is highly stochastic in nature. The networks optimised for their Fit to Median Error are shown to approximate the ground truth more consistently, without sacrificing conventional Minkowski-r error values.

BOLD Amplitude Correlates of Preclinical Alzheimer's Disease.

Alzheimer's disease (AD) is characterized by a long preclinical stage during which molecular markers of amyloid beta and tau pathology rise, but there is minimal neurodegeneration or cognitive decline. Previous literature suggests that measures of brain function might be more sensitive to neuropathologic burden during the preclinical stage of AD than conventional measures of macrostructure, such as cortical thickness. However, among studies that used resting-state functional Magnetic Resonance Imaging (fMRI) acquisitions with Blood Oxygenation Level Dependent (BOLD) contrast, most employed connectivity-based analytic approaches, which discard information about the amplitude of spontaneous brain activity. Consequently, little is known about the effects of amyloid and tau pathology on BOLD amplitude. To address this knowledge gap, we characterized the effects of preclinical and prodromal AD on the amplitude of low-frequency fluctuations (ALFF) of the BOLD signal both at the whole-brain level and, at a more granular level, focused on subregions of the medial temporal lobe. We observed reduced ALFF in both preclinical and prodromal AD. In preclinical AD, amyloid positivity was associated with a spatially diffuse ALFF reduction in the frontal, medial parietal, and lateral temporal association cortices, while tau pathology was negatively associated with ALFF in the entorhinal cortex. These ALFF effects were observed in the absence of observable macrostructural changes in preclinical AD and remained after adjusting for structural atrophy in prodromal AD, indicating that ALFF offers additional sensitivity to early disease processes beyond what is provided by traditional structural imaging biomarkers of neurodegeneration. We conclude that ALFF may be a promising imaging-based biomarker for assessing the effects of amyloid-clearing immunotherapies in preclinical AD.

Electromagnetic bone segment tracking in multiplanar osteotomies: A saw bone study.

Computer assisted orthopedic surgery is used to improve precision. Electro-magnetic tracking has been shown to improve precision in mono-planar derotational osteotomies. However, studies are lacking to investigate its use in multiplanar osteotomies. For this purpose, 60 complex (derotation and extension) osteotomies were performed in standardized sawbones. Correction amount was randomly planned before the procedures. In 30 bones, the amount of correction was determined intraoperatively using conventional goniometric measurement while in the other 30 bones electro-magnetic tracking was used to guide the amount of correction. CT-scans were done before and after the procedures in all bones and the amount of correction was determined to compare the precision of the two techniques. Electromagnetic tracking resulted in a precision of 2.25° ± 1.77° for derotation and 1.38° ± 1.29° for extension, while precision for the conventional method was significantly lower. There was a significant relationship between goniometer measurement deviation and the absolute angle change for derotation and extension measurements with larger deviations for greater angle changes. For the electro-magnetic tracking, this correlation was observed only for derotation measurement. Electro-magnetic tracking represents an accurate method to control complex, multiplanar corrective osteotomies with superior precision in comparison to conventional goniometric measurement. Further research is needed to investigate the in-vivo accuracy and the effects on clinical outcome.

Beyond conventional measures: left atrial reservoir strain as a superior prognostic marker for all-cause mortality in HFpEF

Abstract Background Considerable data are available concerning improvements in diagnostic approaches over recent years for the treatment of heart failure with reduced ejection fraction (HFrEF). Conversely, regarding heart failure with preserved ejection fraction (HFpEF), there has been relatively little change in terms of therapy and prognostic stratification. Many efforts have been made to phenotype HFpEF spectrum, aiming to identify simple and reliable tools for recognizing patients at high risk for mortality. Purpose The aim of the present study is to identify a prognostic tool for all-cause mortality in patients with HFpEF. Methods From 2013 to 2024 thirty-eight HFpEF patients who underwent both transthoracic echocardiography at rest and cardiopulmonary exercise test (CPET) combined with echocardiography have been enrolled. Patients with established cardiomyopathy, such as hypertrophic cardiomyopathy and cardiac amyloidosis, have been excluded from the analysis. Mean follow-up period was 3,7 years. Primary outcome was all-cause mortality. Results Sixteen patients (42%) died during the study's follow-up period. No statistically significant differences were found for clinical, demographic, and therapeutic variables. Among all echocardiographic parameters, both at rest and during exertion, E/e' at rest (12 [8.9-19] vs. 17 [12-33], p-value 0.023), SPAP at rest and during exertion (31 ± 7 vs. 43 ± 16, p-value 0.021 and 51 ± 10 vs. 66 ± 17, p-value 0.019), TAPSE/SPAP at rest and during exertion (0.67 ± 0.15 vs. 0.47 ± 0.20, p-value 0.005 and 0.48 ± 0.15 vs. 0.33 ± 0.12, p-value 0.019), and left atrial reservoir function (22 [15-29] vs. 9.4 [6-15], p-value 0.001) were significantly associated with all-cause mortality (Table 1). Among CPET variables, respiratory exchange rate and oxygen pulse were associated with all-cause mortality (1.1 ± 0.13 vs. 1.18 ± 0.15, p-value 0.021 and 10 [7-11] vs. 8.1 [5.4-8.7], p-value 0.008) (Table 1). In multivariate analysis, the only independent predictor of mortality was left atrial reservoir function (p-value 0.026, OR 1.17 [1.02-1.35]). The optimal cutoff was identified using the Youden Index analysis (cut-off: 16.4%, sensitivity 85%, specificity 68%; AUC 0.839 [0.710-0.969]) (Figure 1). Survival curves based on the optimal cutoff are reported in Figure 1. Conclusions In a cohort of patients with HFpEF the left atrial reservoir function remains an important prognostic determinant for all-cause mortality. These results highlight the importance of estimating left ventricular filling pressures which are higher in patients diagnosed with HFPEF due to diminished ventricular compliance. Further studies with a larger cohort are needed to confirm these preliminary data.

Associations between heart rate, deformational echocardiographic parameters and clinical outcomes in patients with atrial fibrillation

Abstract Background The relationship between baseline heart rates and cardiac function in patients with atrial fibrillation (AF) remains unknown, as does its impact on long-term outcomes. Methods Patients with newly diagnosed AF and available echocardiography images were included. Conventional echocardiography measurement and myocardial deformation analyses using two-dimensional speckle-tracking echocardiography were performed during AF. Clinical endpoints included first-time hospitalization for ischemic stroke, heart failure (HF), all-cause mortality, and composite endpoint. Results Patients were categorized into groups according to baseline heart rates: 40-59, 60-69, 70-79, 80-89, 90-99, 100-109, 110-119, and ≥120 beats per minutes (bpm). As heart rates increased, there was a stepwise decrease of peak atrial longitudinal systolic strain (PALS: 14.6 ± 5.3%, 14.7 ± 5.5%, 14.1 ± 4.6%, 13.4 ± 4.7%,12.6 ± 4.9%, 12.1 ± 4.5%, 11.2 ± 5.2% and 10.8±4.1% in 40-59, 60-69, 70-79, 80-89, 90-99, 100-109, 110-119, and ≥120 bpm groups, respectively; P &amp;lt; 0.001)) and LV strain (-13.8 ± 3.9%, -14.5 ± 4.0%, -13.4 ± 3.4%, -13.4 ± 3.6%, -12.5 ± 3.6%, -11.9 ± 3.8%, -10.3 ± 3.8%, and -10.2 ± 3.8%, in 40-59, 60-69, 70-79, 80-89, 90-99, 100-109, 110-119, and ≥120 bpm groups, respectively; P &amp;lt; 0.001)(Figure). The lowest risk of composite endpoint was observed for patients whose heart rate between 60 to 69 bpm (Figure). Compared to the 60-69 heart rate group, faster heart rates were associated with increased risk of ischemic stroke (adjusted hazard ratios [aHR] 4.448 in the ≥120 bpm group), HF (aHR 1.909 in the ≥120 bpm group), mortality (aHRs 2.487, 2.810, 4.569, 4.760 in the 90-99, 100-109, 110-119, and ≥120 bpm groups, respectively), and composite endpoint (aHRs 2.034, 2.349, 3.492 in the 100-109, 110-119, and ≥120 bpm groups, respectively) (all P &amp;lt; 0.05). Conclusion In patients with AF, heart rate is closely linked to cardiac function and plays a pivotal role in long-term prognosis. Faster heart rates were associated with worse LA/LV functions and increased risk of clinical events. Favorable outcomes were found at heart rates below 100 bpm, with even better LA/LV function noted at heart rates below 80 bpm.

Influence of initial state and residual stresses on the modulus-density relationship of geomaterials: insights from multiple experimental setups

ABSTRACT Quality control in pavement construction traditionally relies on density measurements of geomaterials. With the introduction of modulus measurement methods, a shift has occurred due to the operational advantages of modulus-estimating devices over conventional density measurement techniques. Modulus-based methods also provide valuable information for the mechanistic-empirical (ME) design of pavement layers. However, a challenge emerges as a single modulus measurement does not directly correspond to a specific density measurement, leading to concerns about replacing density measurements in quality control processes. While it is generally accepted that a geomaterial's modulus primarily depends on its moisture content and density or void ratio, this study explores the complex relationship between modulus and density, particularly in field scenarios with consistent moisture content. Using three different laboratory-scale test set-ups, characterised by unique loading and boundary conditions, the research highlights the significant role of a geomaterial's initial state in obtaining accurate modulus estimates. The results reveal that identical densities can exhibit variations in modulus due to differences in initial densities and the development of residual lateral stresses. These variations in field conditions often stem from different paving or spreading techniques, emphasising the need for a comprehensive approach when establishing density-modulus correlations..

Comparative assessment of extracellular volume metrics in predicting adverse outcomes in patients with transthyretin amyloid cardiomyopathy

Abstract Introduction The indexed total extracellular volume of the myocardium (iECV) has recently been proposed to be superior in predicting adverse outcome in severe aortic stenosis as compared to conventional extracellular volume (ECV). So far, no study has assessed the comparative predictive performance of both measures in transthyretin amyloid cardiomyopathy (ATTR-CM). Aim We aimed to assess and compare the predictive performance of conventional ECV against iECV in determining adverse outcomes in patients with ATTR-CM. Methods From 2012 to 2023, patients with ATTR-CM undergoing contrast cardiac magnetic resonance (CMR) imaging prior to any specific treatment were enrolled. Both, conventional ECV and iECV were quantified on CMR alongside left ventricular volumetrics and late gadolinium enhancement. Adverse outcome was defined as a composite endpoint of hospitalization for heart failure and/or death. Results Analysis of 178 patients with ATTR-CM (82% males, mean age 77±8 years) revealed a mean conventional ECV of 47±13% and a mean iECV of 46±21 mL/m2, with a median follow-up of 2.5 years (IQR: 1.00-4.08 years). Conventional ECV was significantly associated with the composite endpoint (HR=1.03, 95%CI=1.01–1.05, p=0.006), outperforming iECV (HR=1.01, 95%CI=1.00–1.02, p=0.010). On multivariate analysis, adjusted for age, sex and left ventricular function, conventional ECV remained associated with the composite endpoint (p=0.002), while iECV demonstrated a slightly less significant association (p=0.003). Kaplan-Meier analysis, stratified by conventional ECV tertiles, revealed that patients in the highest tertile (ECV ≥53%) demonstrated the highest event rate (p = 0.043 by log rank test, see Figure 1A), in contrast to iECV (p=NS, Figure 1B). Conclusions High conventional ECV, among CMR fibrosis markers, is linked to heart failure hospitalizations and death in ATTR-CM, demonstrating superior prognostic value compared to iECV. Conventional ECV measurements may offer enhanced risk stratification for patients with ATTR-CM.

Improving early mortality risk detection in light-chain cardiac amyloidosis patients with routine echocardiographic indicators and mayo staging

Abstract Background Light-chain cardiac amyloidosis (AL-CA) is a fatal cardiomyopathy caused by the deposition of monoclonal immunoglobulin light-chain in the cardiac fibers, conduction system, valves, and other parts of the heart. The Mayo 2004 staging system is widely used to assess the prognosis of AL-CA. Those in the highest-risk categories, Mayo 2004 stage IIIb, exhibit extremely poor responses to conventional treatment regimens, resulting in high early mortality rates. However, within the same stage, prognostic outcomes among patients can still vary significantly. Hence, a more detailed stratification of high-risk patients is crucial for pinpointing those at extreme risk. Objective To investigate whether conventional echocardiographic measurements can enhance the identification of high-risk patients with early mortality in AL-CA on the basis of existing risk stratification. Methods Continuous enrollment of patients diagnosed with AL-CA at our center from May 2020 to December 2022. Clinical data, echocardiography, and follow-up results of the patients were collected. Logistic regression analyses were used to identify risk factors for early mortality, with risk factor thresholds calculated using Receiver Operating Characteristic (ROC) curves. Kaplan-Meier survival analysis was employed to assess endpoint events. The diagnostic efficacy of the model was evaluated using the area under the ROC curve and the Integrated Discrimination Improvement (IDI). Results A total of 76 patients were included with an average age of 59±10 years. Among them, 51 were male (67.1%). The median follow-up duration was 10 months (ranging from 5 to 20 months). Early mortality, defined as death within 6 months, occurred in 20 patients (26.3%). Twenty-three patients were categorized under the Mayo 2004 stage IIIb (30.3%). The 6-month mortality rate for patients in the Mayo 2004 stage IIIb was 56.5%. The sensitivity of early diastolic transmitral flow velocity to early diastolic mitral annular tissue velocity ratio divided left ventricular ejection fraction [(E/e’) /LVEF] in predicting early mortality in patients with AL-CA is 63%, and the specificity is 92%.When compared to the Mayo 2004 stage IIIb alone, (E/e')/LVEF≥0.5 combined with the Mayo 2004 stage IIIb had an area under the curve of 0.731 and 0.824, respectively, in the ROC curve. The IDI was 0.113 (95% CI: 0.013-0.213, P=0.026), representing an 11.3% enhancement in the predictive value of early mortality in AL-CA patients. Conclusion Routine echocardiography derived E/e' to LVEF ratio offered added prognostic value for early mortality beyond Mayo staging.Kaplan-Meier survival curve

Myocardial work and aortic valve stenosis cardiac damage stages are predictors of all-cause mortality in patients undergoing transcatheter aortic valve replacement

Abstract In aortic stenosis (AS) patients, assessment of left ventricular (LV) systolic function is complicated due to the significant impact of increased afterload on conventional parameters. Myocardial work (MW) analysis, a novel echocardiographic method adjusts myocardial deformation to instantaneous LV pressure which may better reflect the LV contractile state. Importantly, long-term LV pressure overload has marked backward effects beyond the LV: classification of this extravalvular cardiac damage effectively represents the involvement of the cardiopulmonary system in AS. Both MW and cardiac damage staging could hold remarkable prognostic power in the clinically complex population of transcatheter aortic valve replacement (TAVR) candidates. Accordingly, our aim was to assess the prognostic value of MW analysis and cardiac damage staging in patients undergoing TAVR. We enrolled 289 patients (79±6 years, 41% female) prior to TAVR. Echocardiographic measurements were performed one day before the procedure. We calculated LV ejection fraction (EF) and by speckle-tracking echocardiography global longitudinal strain (GLS), as well. Global constructive work (GCW) was quantified with dedicated software and LV pressure was estimated using transaortic mean gradient and systolic blood pressure. Based on the echocardiographic data, we also determined the extent of cardiac damage associated with AS: patients were classified as Stage 0 (no cardiac damage), Stage 1 (LV damage), Stage 2 (mitral valve or left atrial damage), Stage 3 (pulmonary artery vasculature or tricuspid valve damage), or Stage 4 (right ventricular damage). Our primary outcome was all-cause mortality, reached by 68 patients (median follow-up: 26 months). In our cohort, preprocedural EF was 47±13 %, GLS was -12.3±4 %, while GCW was 2043±791 mmHg%. 14 (5%) patients were classified as Stage 0, 61 (21%) as Stage 1, 128 (44%) as Stage 2, 15 (5%) as Stage 3, and 71 (25%) as Stage 4. GCW showed a continuous decline through the AS Stages (from Stage 0-4: 2963±652 vs. 2154±652 vs. 2168±718 vs. 1988±969 vs. 1552±772 mmHg%; p&amp;lt;0.001). Using univariate Cox analysis GCW (HR 0.968 [95% CI 0.938-0.998] per 100 unit change; p=0.034) and AS Staging (HR 1.236 [95% CI 1.015-1.505]; p=0.035) were both associated with all-cause mortality, while EF (HR 0.984 [95% CI 0.966-1.002]; p=0.085) and GLS (HR 1.042 [95% CI 0.984-1.103]; p=0.160) were not. In multivariate Cox regression models, both GCW (HR 0.957 [95% CI 0.922-0.992] per 100 unit change; p=0.018) and AS cardiac damage staging (HR 1.263 [95% CI 1.029-1.549]; p=0.025) were proven to be significant independent predictors of all-cause mortality. In TAVR patients, preoperative GCW values exhibited a persistent decrease across AS Stages. As opposed to EF and GLS, GCW and AS Staging both showed strong association with all-cause mortality in our cohort. Moreover, GCW had higher prognostic value than any other conventional or advanced measure of LV function.

Overcoming fixation and permeabilization challenges in flow cytometry by optical barcoding and multi-pass acquisition.

The fixation and permeabilization of cells are essential for labeling intracellular biomarkers in flow cytometry. However, these chemical treatments often alter fragile targets, such as cell surface and fluorescent proteins (FPs), and can destroy chemically-sensitive fluorescent labels. This reduces measurement accuracy and introduces compromises into sample workflows, leading to losses in data quality. Here, we demonstrate a novel multi-pass flow cytometry approach to address this long-standing problem. Our technique utilizes individual cell barcoding with laser particles, enabling sequential analysis of the same cells with single-cell resolution maintained. Chemically-fragile protein markers and their fluorochrome conjugates are measured prior to destructive sample processing and adjoined to subsequent measurements of intracellular markers after fixation and permeabilization. We demonstrate the effectiveness of our technique in accurately measuring intracellular FPs and methanol-sensitive antigens and fluorophores, along with various surface and intracellular markers. This approach significantly enhances assay flexibility, enabling accurate and comprehensive cellular analysis without the constraints of conventional one-time measurement flow cytometry. This innovation paves new avenues in flow cytometry for a wide range of applications in immuno-oncology, stem cell research, and cell biology.

REverse transcriptase ACTivity (REACT) assay for point-of-care measurement of established and emerging antiretrovirals for HIV treatment and prevention.

Maintaining adequate levels of antiretroviral (ARV) medications is crucial for the efficacy of HIV treatment and prevention regimens. Monitoring ARV levels can predict or prevent adverse health outcomes like treatment failure or drug resistance. However, conventional ARV measurement using liquid chromatography-tandem mass spectrometry (LC-MS/MS) is slow, expensive, and centralized delaying clinical and behavioral interventions. We previously developed a rapid enzymatic assay for measuring nucleotide reverse transcriptase inhibitors (NRTIs) - the backbone of HIV treatment and prevention regimens - based on the drugs' termination of DNA synthesis by HIV reverse transcriptase (RT) enzyme. Here, we expand our work to include non-nucleoside reverse transcriptase inhibitors (NNRTIs) - an ARV class used in established and emerging HIV treatment and prevention regimens. We demonstrate that the REverse Transcriptase ACTivity (REACT) assay can detect NNRTIs including medications used in oral and long-acting/extended-release HIV treatment and prevention. We demonstrate that REACT can measure NNRTIs spiked in either buffer or diluted plasma and that fluorescence can be measured on both a traditional plate reader and an inexpensive portable reader that can be deployed in point-of-care (POC) settings. REACT measured clinically relevant concentrations of five NNRTIs spiked in aqueous buffer. REACT measurements showed excellent agreement between the plate reader and the portable reader, with a high correlation in both aqueous buffer (Pearson's r = 0.9807, P < 0.0001) and diluted plasma (Pearson's r = 0.9681, P < 0.0001). REACT has the potential to provide rapid measurement of NNRTIs in POC settings and may help to improve HIV treatment and prevention outcomes.

Left ventricular late diastolic strain rate predicts cardiovascular mortality in patients with heart failure with reduced ejection fraction

Abstract Background Left ventricular (LV) strain rate measures provide detailed information regarding LV contraction and filling pressures. These include global systolic strain rate (GSRs), early and late diastolic strain rates (GSRe and GSRa), and ratio of transmitral early filling velocity to GSRe (E/GSRe). Purpose To investigate the prognostic value of strain rate measures with regard to cardiovascular mortality in patients with heart failure with reduced ejection fraction (HFrEF). Methods The study population was retrospectively included from a HF clinic and consisted of patients with LV ejection fraction (LVEF) ≤45%. Echocardiography was obtained within 1 year of referral. The study endpoint was cardiovascular mortality, which was analysed using univariable and adjusted Cox proportional hazards models. Incremental prognostic information was assessed using Harrell’s C-index and continuous net reclassification improvement (NRI). Cubic spline analysis was used to dichotomise variables at a hazard ratio (HR) of 1 for better interpretability. Results The final study population consisted of 1160 patients with HFrEF (mean age 68±11.8 years, 72.7% male, LV ejection fraction (LVEF) 28.6±9.9%). During follow-up (median 10.1 years, IQR: 4.7-13.0), 333 (28.7%) met the outcome. Subjects who met the outcome generally had higher age and prevalence of male sex, a higher burden of comorbidities, and more severely impaired conventional echocardiographic parameters. All four strain rate measures were significantly associated with cardiovascular mortality (GSRs: HR 16.88 95% CI [8.42, 33.84] per 1 s-1 increase, GSRe: HR 0.29 [0.18, 0.47] per 1 s-1 increase, E/GSRe ratio: HR 1.31 [1.22, 1.41] per 1 unit increase, GSRa: HR 0.15 95% CI [0.23, 0.65] per 1 s-1 increase, p&amp;lt;0.0001 for all). However, only GSRa remained an independent predictor in multivariable Cox regression after adjustment for clinical risk factors including sex, age, mean arterial pressure, heart rate, body mass index, cigarette pack years, diabetes mellitus, total cholesterol, ischemic heart disease, and echocardiographic factors including LVEF, global longitudinal strain, tricuspid annular plane systolic excursion, LV mass index, LV internal diameter index, E/e’ ratio and left atrial volume index (HR 0.39 [0.23,0.65], p=0.0003). Furthermore, GSRa provided incremental prognostic information to a model containing all aforementioned parameters (Harrell’s C-index 0.789 vs. 0.792 and continuous NRI 0.158). GSRa was dichotomised at 0.5 s-1, and a Kaplan-Meier curve stratified according to this was plotted (log rank p&amp;lt;0.0001)(Figure 2). Conclusion GSRa is an independent predictor of cardiovascular mortality in patients with HFrEF after multivariable adjustment. GSRa provides incremental prognostic value over conventional echocardiographic measures in risk stratification of HFrEF patients. Our results suggest an increased risk of cardiovascular mortality associated with a GSRa below 0.5 s-1.Figure 1:Spline of HR according to GSRaFigure 2:Kaplan-Meier curve

Monitoring the level of health and inequality over time using the Population Health Performance Index

Abstract Background The Population Health Performance Index (PHPI) is a composite measure that combines average health outcomes and their distribution within a population, thereby allowing for a comprehensive assessment of population health and inequality. The aim of this study is to examine the extent to which the PHPI adds value to monitoring of health and inequality over time in comparison to absolute and relative inequality. Methods Data from the WHO Equity Monitor database on under-5 mortality disaggregated by wealth quintiles for Nepal, Ethiopia, Peru, Rwanda, and Zimbabwe were analysed using different years between 1994 and 2020. Descriptive comparative statistics were employed to assess trends in the PHPI and conventional pairwise measures of absolute and relative inequalities, with consideration of different weights for inequality aversion. Results PHPI trends correspond to the trend of absolute inequality in all five countries, although they exhibit less volatility over time. Relative inequality follows the trend of the PHPI in only two of the five countries (Ethiopia and Zimbabwe), reflecting the methodology utilised for the PHPI. PHPI scores vary based on different inequality aversion weights, highlighting the sensitivity of the index to methodological adjustments. Conclusions The PHPI demonstrates notable convergence of trends with conventional methods, thereby substantiating its utility as a comprehensive tool for the simultaneous measurement of health and inequality. As it is able to consider both absolute and relative inequality within its own calculations, the PHPI allows for independent analysis of its two key components. The PHPI facilitates a more nuanced understanding of population health and may be more easily understood by policymakers and other stakeholders. As it does not address the underlying causes of changes in health inequalities, further research is necessary to supplement monitoring activities. Key messages • PHPI is a valuable tool for health and inequality monitoring by integrating both average health and disparity in a single index, facilitating communication of trends over time. • The dual focus complements conventional methods with its multidimensionality and may enable stakeholders to assess health and inequalities in alignment with broader health policy objectives.

Invasive validation of central blood pressure measurements using a suprasystolic monitor

Abstract Interest in the assessment of Central Blood Pressure (cBP) is steadily growing since it is a better predictor of myocardial infarction, stroke, or death than Peripheral Blood Pressure (pBP). However, pBP remains the first line for the diagnosis of hypertension (HTN) due to the ease and speed of the measurement. We sought to validate a new method to estimate cBP from brachial sphygmomanometer measurements. We estimated cBP using a sphygmomanometer that can record, after conventional pBP measurements, the pressure in the cuff maintained at a constant suprasystolic pressure. cBP is calculated using a method based on applying a physics-based model of the left subclavian artery to the brachial arterial branch to the suprasystolic brachial artery pressure waveforms. We compared this noninvasive estimated cBP to an invasive gold-standard measurement during cardiac catheterization. After clinically indicated cardiac catheterization requiring a haemodynamic assessment of a moderate coronary artery stenosis by Fractional Flow Reserve (FFR), the wire that incorporates a high fidelity electronic pressure transducer was positioned into the guiding catheter left in the ascending aorta. Simultaneous measurements were performed with a cuff placed on the patient's left arm. The output signals were recorded in a custom-based acquisition system. The comparison was obtained on the same 10 seconds recorded by the cuff and the pressure wire. The goal will be to reach 85 patients as recommended by the ARTERY Society Task Force. It recommends as an accuracy criterion to achieve a mean difference ≤ 5 mmHg with a standard deviation (SD) ≤ 8 mmHg, which are the standards adopted for this study. Patients with aortic stenosis, atrial fibrillation, or frequent (supra)ventricular extrasystoles were excluded. A total of 197 pairs of measured-estimated cBP were analysed in 78 patients with a mean age of 63 ± 8 yo, 75% of whom were men, 70% had hypertension, 26% fdiabetes, 93% dyslipidemia, 41% were tobacco users and 14% suffered from clinical peripheral artery diseases without history of revascularization. The median (InterQuartiles 25-75%) pBP was 123 [112 134] / 70 [64 77] mmHg. Measured cBP was 102 [92 11] / 78 [70 84] mmHg with a central augmentation index of 34 [23 44] %. The mean difference between estimated and measured systolic cBP was 4.9 ± 6.5 mmHg, while it was -3.9 ± 5.8 mmHg for diastolic cBP, meeting the prespecified accuracy criteria. In conclusion, our approach based on an exact matching and comparison of non-invasive suprasystolic arm cuff measurements and high-fidelity aortic BP validates that an estimation of central aortic blood pressure that can be easily carried out in daily practice and might improve HTN management. It remains to be demonstrated that more cardiovascular complications will be avoided by guiding the antihypertensive therapy with cBP instead of pBP measurements.Bland-Altman of estimated - measured cBP

Feasibility, accuracy, and reproducibility of device sizing in virtual reality for percutaneous left atrial appendage closure - a single center study

Abstract Background Left atrial appendage closure (LAAC) is a safe and effective procedure for stroke prevention in patient with non-valvular atrial fibrillation. Procedural planning and device sizing remains challenging due to the highly complex and variable three-dimensional (3D) anatomy of the left atrial appendage (LAA). Virtual reality (VR) is a innovative, recent technology allowing a superior spatial orientation visualization of 3D imaging datasets. Purpose Therefore, we aimed to evaluate feasibility and accuracy of LAA measurements in VR for device sizing in patients planned for LAAC. Methods Twenty-one patients (79±7 years, 62% male) with non-valvular atrial fibrillation scheduled for LAAC were randomly included in our study. Preprocedural a multi-slice computed tomography (MSCT) was performed for device sizing in all patients. MSCT-based 3D models were established and visualized in VR using a dedicated software (VMersive, Warsaw, Poland). LAA dimensions (Ostium, landing zone (LZ), and depth) were assessed directly in the virtual environment. Conventional measurements of LAA ostium, landing zone (LZ) and depth using commercially available software were compared to measurements in VR. Results 3D reconstruction of MSCT datasets and visualization in VR were successfully performed automatically in all patients within a few seconds. MSCT and VR demonstrated good correlations for ostium minimum (r = 0.93), maximum (r = 0.8) and mean (r = 0.88, all p&amp;lt;0.001) diameters. Additionally, LZ minimum (r=0.84), maximum (r=0.86) and mean (r=0.9) diameters showed good correlation (all p&amp;lt;0.001). Moderate correlation was observed for depth measurements (r=0.76, p&amp;lt;0.001). Furthermore, intraclass correlation coefficients ranging from 0.88 to 0.98 denoted high inter- and intraobserver agreement. Conclusion Immersive VR allows highly feasible, accurate and reproducible measurements of the LAA dimensions directly in the virtual environment, hence enabling accurate device sizing for LAAC.

Comparative Study of Indium Oxide Films for High‐Mobility TFTs: ALD, PLD and Solution Process

AbstractDeposition of indium oxide base films for high‐mobility thin film transistors (TFTs) has been an important part in the implementation of high‐resolution and high‐frequency display back panels. In this study, three types of In2O3 (InO) films have been fabricated for TFTs using atomic layer deposition (ALD), pulsed laser deposition (PLD), and solution process, respectively. ALD‐derived InO films show controllable grain formation and optimized TFTs show the field effect mobility of ≈100 cm2 V−1s−1 in both the conventional transistor measurements and critical four‐probe measurements, reaching the level of low‐temperature polycrystalline silicon (LTPS). Combined spectroscopy investigations show that the ALD‐derived InO film features advantages as compared to those of the PLD‐deposited and solution‐processed InO film in providing a smoother surface morphology, good crystallinity, and more orderly atomic growth mode. Moreover, the bias‐stress stability of ALD‐derived TFTs can be improved with further passivation.