Threshold Estimation Research Articles

Does institutional quality matter in the financial Development-Economic complexity Nexus? Empirical insights from Africa

PurposeThis study examines the moderating role of institutional quality and its threshold in the African financial development-economic complexity nexus. This objective follows the argument that institutional quality influences the financial system's efficiency in allocating resources to innovative initiatives and activities that increase productivity knowledge and technical capabilities in an economy's production system to produce complex products and exports. Design/methodology/approachTo achieve these objectives, this study adopts novel and robust approaches such as the system generalized method of moments (GMM), the Driscoll-Kraay nonparametric covariance matrix estimator (DK), the method of moments quantile regression, and a dynamic panel threshold to analyze the annual dataset of 29 African countries covering 1995–2020. FindingsThis study establishes robust and persistent evidence of interdependence, intertwining, and heterogeneity among African countries. Both mean-based (GMM and DK) and quantile regressions consistently demonstrate that financial development and institutional quality separately enhance Africa's economic complexity across quantiles. In contrast, institutional quality drains financial development's contribution to economic complexity when the coefficients are significant. The moment-quantile regression reveals that institutional quality complements financial development to support economic complexity from the 10th to 30th quantiles, but the coefficients are insignificant. The threshold estimation confirms nonlinearity and the institutional quality threshold estimate is 5.73 on the ordinal scale of 10. On average, only six African countries exceed the threshold, while others operate below the benchmark. Research limitations/implicationsBased on the findings, African financial systems operate within weak institutional frameworks. These phenomena allow rent-seeking, opportunism, corruption, and sharp practices, which divert financial resources from innovative activities and investments in research and development, human capital development, technology, high-tech infrastructure, and entrepreneurial innovation. As a result, Africa's institutional quality impairs the financial sector's ability to spur economic complexity upgrades. African economies need better institutional architectures to maximize financial development's benefits of upgrading economic complexity. The policy implications and recommendations of this study are more relevant to African settings and situations. Thus, other scholars are encouraged to conduct similar research for other continents to enrich the study’s outcomes. Originality/valueThe following are the highlights of this study's novelties: 1.) To the best of the authors' knowledge, this is the first study to examine the moderating role of institutional quality in the financial development-economic complexity nexus in Africa using estimators that account for cross-sectional dependence, distributional effects, and heterogeneous effects (the Driscoll-Kraay nonparametric covariance matrix estimator (DK) and the method of moment quantile regression). 2.) Unlike earlier research, this study establishes a threshold of institutional quality in the financial development-economic complexity nexus. We propose that the institutional structures that govern Africa's financial systems be examined and trimmed. This move helps to phase out the inherent inadequaciesthat drain financial development's contributions to economic complexity.

A new wavelet-based estimation of conditional density via block threshold method

A new wavelet-based estimator of the conditional density is investigated. The estimator is constructed by combining a special ratio technique and applying a non negative estimator to the density function in the denominator. We used a wavelet shrinkage technique to find an adaptive estimator for this problem. In particular, a block thresholding estimator is proposed, and we prove that it enjoys powerful mean integrated squared error properties over Besov balls. Moreover, it is shown that convergence rates for the mean integrated squared error (MISE) of the adaptive estimator are optimal under some mild assumptions. Finally, a numerical example has been considered to illustrate the performance of the estimator.

Threshold Estimation and Speech Perception Under Hearing Loss Simulation: Examination of the Immersive Hearing Loss and Prosthesis Simulator

Purpose: Hearing loss simulation (HLS) has been recommended for clinical teaching and counseling of patients and their families, so that they can experience hearing impairment. However, few validated procedures for simulating hearing loss are available to instructors and practicing clinicians. The aim of this study was to assess the accuracy of the Immersive Hearing Loss and Prosthesis Simulator (I-HeLPS) on reducing hearing sensitivity and word recognition to determine its adequacy for educational and clinical use. Method: Thirty-seven young adults with normal hearing completed hearing threshold and word recognition testing under normal and simulated hearing losses. The accuracy of the nominal hearing threshold settings within the I-HeLPS software was assessed with behavioral detection of frequency-modulated pure tones presented in a calibrated sound field, while listeners wore I-HeLPS headphones. The impact of the HLSs on speech perception was measured using the California Consonant Test. Hearing thresholds, word identification accuracy, and sound confusions were compared across listening conditions. Results: Hearing thresholds increased systematically with worse simulated hearing loss. Performance on the California Consonant Test worsened, and the number of phoneme confusions increased with simulated hearing loss severity. Most of the confusions were place confusions with near neighbors and manner confusions increased as a function of increasing severity of simulated hearing loss. Conclusions: The I-HeLPS accurately elevated hearing thresholds with increasing HLS severity and impacted word recognition in a manner consistent with sensorineural hearing loss. The simulations were considered reasonable for educational and clinical purposes. Supplemental Material: https://doi.org/10.23641/asha.24520966

Visual motion detection thresholds can be reliably measured during walking and standing.

In upright standing and walking, the motion of the body relative to the environment is estimated from a combination of visual, vestibular, and somatosensory cues. Associations between vestibular or somatosensory impairments and balance problems are well established, but less is known whether visual motion detection thresholds affect upright balance control. Typically, visual motion threshold values are measured while sitting, with the head fixated to eliminate self-motion. In this study we investigated whether visual motion detection thresholds: (1) can be reliably measured during standing and walking in the presence of natural self-motion; and (2) differ during standing and walking. Twenty-nine subjects stood on and walked on a self-paced, instrumented treadmill inside a virtual visual environment projected on a large dome. Participants performed a two-alternative forced choice experiment in which they discriminated between a counterclockwise ("left") and clockwise ("right") rotation of a visual scene. A 6-down 1-up adaptive staircase algorithm was implemented to change the amplitude of the rotation. A psychometric fit to the participants' binary responses provided an estimate for the detection threshold. We found strong correlations between the repeated measurements in both the walking (R = 0.84, p < 0.001) and the standing condition (R = 0.73, p < 0.001) as well as good agreement between the repeated measures with Bland-Altman plots. Average thresholds during walking (mean = 1.04°, SD = 0.43°) were significantly higher than during standing (mean = 0.73°, SD = 0.47°). Visual motion detection thresholds can be reliably measured during both walking and standing, and thresholds are higher during walking.

The relative impact of traditional and digital financial inclusion on economic growth: a threshold regression-based comparative analysis

ABSTRACT This study examines the effect of traditional and digital financial inclusion on economic growth in 130 developed and developing countries in 2014 and 2017. The motivation behind this study emerges from the critical need to discern not only how traditional and digital financial inclusion individually influence economic growth, but also to compare their relative contributions. In addition, there exists a potential non-linear relationship between traditional and digital financial inclusion, wherein both forms of financial inclusion can exert a positive influence on economic growth up to a specific threshold. For this purpose, traditional and digital financial inclusion indices were developed as distinct measures to investigate the relative contribution of each to economic growth. Cross-sectional sample splitting and threshold estimation were utilised to analyse whether the effects of each financial inclusion index on economic growth varied across different levels of digital and traditional financial inclusion. This study yielded two notable findings. First, the effect of traditional financial inclusion on economic growth is pronounced in countries with low levels of inclusion. Second, digital financial inclusion has a greater positive impact on economic growth in countries with higher levels of digital financial inclusion.

Features of Narrowband Stimulated Electromagnetic Emission Depending on the Effective Radiated Power of the EISCAT/Heating Facility

Estimates of excitation thresholds and the analysis of spectral features of narrowband stimulated electromagnetic emission (NSEE) depending on the electric-field intensity of an extraordinary polarized HF pump wave have been carried out. They are based on results obtained during power stepping EISCAT/Heating experiments. The HF pump wave was radiated toward the magnetic zenith at frequency of 5.423 MHz. The effective radiated power was changed from 55 to 360 MW. NSEE was recorded in the vicinity of St. Petersburg at a distance of ~1200 km away of the EISCAT/Heating facility. Calculations of the electric field of a powerful HF radio wave near the reflection altitude taking into account the nondeviation absorption in the underlying layers were performed. The threshold (minimum) values of the electric field required for the NSEE excitation were determined.

Study on Estimation of Typhoon Damage Thresholds in Coastal Region

Typhoon damage in coastal areas is a complex disaster characterized by heavy rain, strong winds, and turbulent waves. The strength of these strong winds and waves is determined by the intensity of the typhoon. In this study, a variable representing strong winds and waves was developed. A damage prediction model using rainfall, wind, and the developed variable was then proposed and thresholds for each variable were calculated across cities, counties, and districts located in coastal areas. Two damage prediction models were compared based on variables. Standard normal variables related to strong winds and rainfall by duration were calculated using Empirical Copula. The first logistic regression model was constructed using these variables. The second model used a multiple logistic regression model, considering strong winds and rainfall by duration. Although there are more cities, counties, and districts where the multiple logistic regression model exhibited better accuracy, there have been several instances where the typhoon damage induction threshold suggested by this model was abnormal. On the other hand, a relatively stable critical value was yielded using standard normal variables by Empirical Copula. This is because standard normal variables are calculated based on the probability according to the order of rainfall and strong wind magnitude. Hence, the critical value falls within the minimum and maximum range of observed values. According to the research results, it is possible to predict whether typhoon damage will occur in cities, counties, and districts located in coastal areas using the typhoon information provided by the Korea Meteorological Administration during a typhoon event, which can aid in preparing for typhoon disasters.

Investigations into the Influence of Matrix Dimensions and Number of Iterations on the Percolation Phenomenon for Direct Current

The paper presents studies of the site percolation phenomenon for square matrixes with dimensions L = 55, 101 and 151 using the Monte Carlo computer simulation method. The number of iterations for each matrix was 5 × 106. An in-depth analysis of the test results using the metrological approach consisting of determining the uncertainty of estimating the results of iterations with statistical methods was performed. It was established that the statistical distribution of the percolation threshold value is a normal distribution. The coefficients of determination for the simulation results in approximations of the percolation threshold using the normal distribution for the number of iterations 5 × 106 are 0.9984, 0.9990 and 0.9993 for matrixes with dimensions 55, 101 and 151, respectively. The average value of the percolation threshold for relatively small numbers of iterations varies in a small range. For large numbers of iterations, this value stabilises and practically does not depend on the dimensions of the matrix. The value of the standard deviation of the percolation threshold for small numbers of iterations also fluctuates to a small extent. For a large number of iterations, the standard deviation values reach a steady state. Along with the increase in the dimensions of the matrix, there is a clear decrease in the value of the standard deviation. Its value is about 0.0243, about 0.01 and about 0.012 for matrixes with dimensions 55, 101 and 151 for the number of iterations 5 × 106. The mean values of the percolation threshold and the uncertainty of its determination are (0.5927046 ± 1.1 × 10−5), (0.5927072 ± 7.13 × 10−6) and (0.5927135 ± 5.33 × 10−6), respectively. It was found that the application of the metrological approach to the analysis of the percolation phenomenon simulation results allowed for the development of a new method of optimizing the determination and reducing the uncertainty of the percolation threshold estimation. It consists in selecting the dimensions of the matrix and the number of iterations in order to obtain the assumed uncertainty in determining the percolation threshold. Such a procedure can be used to simulate the percolation phenomenon and to estimate the value of the percolation threshold and its uncertainty in matrices with other matrix shapes than square ones.

A robust adaptive-thresholding primal-dual sparse recovery for THz imaging

Terahertz time-domain spectroscopy (THz-TDS) system is a powerful tool in material spectral analysis and non-destructive testing (NDT). However, the data acquisition is time-consuming due to the point-by-point scanning process, which leads to limitations in THz imaging applications. In this paper, a robust adaptive-thresholding primal-dual sparse recovery (APSR) method is proposed to reconstruct high-resolution THz images and reduce the acquisition time. A sparsity averaging dictionary, which is a concatenate of multiple bases, is applied to improve the robustness and generalization. A reweighted scheme is also adopted to enhance the sparse solution. As a crucial consideration in the sparse recovery method, we propose a robust adaptive threshold estimator based on the median absolute deviation in the sense that the final threshold determines the reconstruction quality and the convergence rate. Meanwhile, together with the Nesterov acceleration technique, a large threshold can be applied at the beginning of the iteration to help accelerate the convergence. Numerical experiments demonstrate that the APSR method can reconstruct THz images with robustness even with low SNR (of 30 dB) and low sampling rate (of 30%) compared to conventional methods. In the real THz-TDS system, our proposed sparse imaging method can successfully recover a composite object with much fewer THz spectra and reduces the acquisition time to 30% at the cost of a relative error of 2.5%, demonstrating the efficiency of our proposed method and the penetrating ability of THz technology in the NDT applications.

Are conversation and whispered voice hearing tests comparable to pure tone audiometry for assessment of hearing loss? A retrospective analysis

BackgroundPure tone audiometry (PTA) is considered the standard method of hearing assessment. However, technical and logistical challenges preclude its usage for hearing screening at primary healthcare facilities. Free field hearing (FFH) tests such as conversation voice (CV) and whispered voice (WV) tests have been used for hearing assessment. However, their correlation to PTA and accuracy in detection of hearing loss are doubtful. This study aims to determine if FFH tests can be used for estimation of hearing thresholds. MethodsA retrospective analytical study was conducted at the otorhinolaryngology department. Spearman's correlation coefficient (ρ) was determined between FFH recognition distance and average air conduction PTA thresholds. A statistical regression model was developed to estimate hearing thresholds from the FFH recognition distance. The FFH tests were studied for their accuracy in detection of hearing loss. ResultsThe audiometric records of 437 persons (874 ears) were analysed. The CV and WV tests were found to have a high correlation (ρ = −0.757 and −0.758, respectively) with average PTA thresholds in persons with hearing loss. The WV test was found to have a 94.7% sensitivity, 90.8% specificity, 97.6% positive predictive value, 80.9% negative predictive value, and 93.9% accuracy in detection of hearing loss. ConclusionFFH tests such as WV test can be used to estimate the hearing thresholds and screen for hearing loss when audiometric tests are not logistically feasible, such as at primary-level healthcare facilities, remote locations, and in schools. However, such tests should not be regarded as a substitute to PTA.

Comparing Classical and Bayesian Panel Kink Regression Frameworks in Estimating the Impact of Economic Freedom on Economic Growth

This study aims to accomplish three main tasks. Firstly, it seeks to determine the more appropriate choice between classical and Bayesian methods in estimating a pooled panel kink regression model under the condition of a known but bounded policy variable choice that serves as a kink point. Secondly, as a product of the first target, the study seeks to provide empirical evidence for the economic growth–economic freedom nexus in five top-performing economies in Sub-Saharan Africa. Using index explanatory variables, which are bounded between 0 and 100, and using both numerical and graphical methods, the findings show that the use of the Bayesian method is more appropriate in characterizing the data than the classical OLS framework, as the former better accounts for randomness via the use of posterior distributions. Finally, the study further employed both threshold and Bayesian pooled panel kink regressions, with mixed results. The Bai–Perron test confirmed that the economic freedom index has a single threshold value of 56.70. Whereas the threshold estimates show a negative impact of economic freedom on growth in both low and high regimes, the Bayesian estimates reveal that economic freedom has a negative impact on growth in a low regime but a positive impact in a high regime. Our novel findings show that there exists a nonlinear impact of economic freedom on growth. This provides some guidance and caution in charting policy paths that seek to achieve economic growth.

Integrating Estimation of Inflation Threshold and Nowcasting Regional Economic Growth Using Classical, Machine Learning, and Ensemble Method

In line with the global economic recovery, Indonesia's post-pandemic economic recovery is experiencing major challenge caused by uncertainty due to increasing inflationary pressure. Efforts to reduce inflationary fluctuations were carried out by the government in order to maintain optimal economic growth under the inflation targeting policy framework. Hence it is necessary to inspect the inflation threshold for economic growth in determining the inflation target. This study attempts to integrate inflation threshold estimation and nowcasting modelling of regional economic growth as an early warning system for achieving the government's economic growth target by utilizing several classical, machine learning, and ensemble models. Threshold estimation for the National level and East Java is applied to provincial groups obtained from clustering time series with dynamic time wrapping (DTW), author's justification, and the west-east region. In addition, estimates were also carried out in the period before Covid-19 as well as the entire period and the addition of predictor variables to test the sensitivity of the inflation threshold estimate. The results show that there was a non-linear relationship between inflation and economic growth with an inverted U shape. There are differences in the inflation threshold range due to provincial groupings, addition of control variables, both for the National level and for East Java. Evaluation of the inflation level in East Java and eight cities shows that in several periods, East Java inflation has exceeded Bank Indonesia's ITF target. Taking into account the estimated threshold range, it is recommended to set a more flexible inflation target at the regional economic level. Finally, the results of nowcasting with several specifications, such as the use of machine learning models and weighted ensemble models based on accuracy, as well as out-sample predictions with one-step ahead can improve the accuracy and consistency of the model for both short-term and long-term.

Psychometric evaluation of the Worst Pruritus Numerical Rating Scale (NRS), Atopic Dermatitis Symptom Scale (ADerm-SS), and Atopic Dermatitis Impact Scale (ADerm-IS)

Background Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by pruritus, skin pain, and sleep impacts, which are only reportable by patients themselves. The goal of this research is to evaluate the reliability, validity, and interpretability of the scores from three patient-reported outcome measures within the context of a clinical trial for adolescents and adults with moderate to severe AD. Methods Data from a Phase 3 randomized, double-blind, placebo-controlled, multinational clinical trial for individuals 12–75 years of age with moderate to severe AD (AD Up [ClinicalTrials.gov NCT03568318]) were used to assess the reliability, validity, and interpretability of scores on the Worst Pruritus Numerical Rating Scale (NRS) and the Atopic Dermatitis Symptom and Impact Scales (ADerm-SS and ADerm-IS). Analyses were conducted separately for the adult and adolescent subgroups. Results Of the 882 participants included in the psychometric analyses, the majority were adults (n = 769, 87.2%), male (n = 536, 60.8%), and white (n = 630, 71.4%). Multi-item scores from the ADerm-SS and ADerm-IS had good internal consistency reliability, and most scores demonstrated acceptable test-retest reliability. Scores from the three questionnaires demonstrated adequate validity, exhibiting correlations with other conceptually related outcome assessments and score differences between clinically distinct subgroups. Finally, the score interpretation analyses provide estimates for meaningful within-person change and between-groups difference thresholds that may be useful for future research in adults and adolescents with moderate to severe AD. Conclusions These results provide evidence that the scores produced by the Worst Pruritus NRS, ADerm-SS, and ADerm-IS are reliable and construct-valid when completed by adults and adolescents with moderate to severe AD in a clinical trial setting. The results presented here expand upon the previous qualitative evidence of these tools and provide further support for their use in future clinical studies. While results are specific to clinical trials, next steps would be to evaluate the use of these questionnaires in clinical practice. This can provide clinicians and dermatologists a window into the patient’s disease experience outside of the clinic, aid in shared decision making, and support a patient-centric approach to management of moderate to severe AD.

Effects of mixed heavy metals on obstructive lung function: findings from epidemiological and toxicogenomic data.

The molecular mechanisms and associations of mixed heavy metals (lead, mercury, and cadmium) on obstructive lung function (OLF) in males and females remain unknown. Here, we evaluated the interaction between the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio and three common heavy metals in males and females (n = 6221). Molecular processes involved in OLF development caused by mixed heavy metals were also identified to corroborate the earlier findings. In both males and females, as well as across the entire population, we found that serum cadmium levels were inversely related to the FEV1/FVC ratio. Interactions between serum cadmium and lead, as well as cadmium and mercury, were observed in relation to the FEV1/FVC ratio. Additionally, we observed negative correlations between the FEV1/FVC ratio and mixed serum cadmium, lead, and mercury in both men and women as well as in the overall population. Seven genes were identified as contributing to the etiology of OLF and targeted by combined heavy metals in silico analysis (CYP1A1, CRP, CXCL8, HMOX1, IL6, NOS2, and TNF). The primary relationships between these genes were co-expression interactions. The significant transcription factors and miRNAs associated with OLF and a combination of the examined heavy metals were identified as NFKB2, hsa-miR-155-5p, and hsa-miR-203a-3p. The main biological processes involved in the emergence of OLF induced by mixed heavy metals were listed as inflammatory and oxidative stress pathways, lung fibrosis, chronic obstructive pulmonary disease, as well as cytokine activity, monooxygenase activity, oxidoreductase activity, and interleukin-8 production. Threshold estimations and miRNA sponge patterns for heavy metal exposure levels associated with OLF were evaluated for both males and females. This study found that cadmium plays the most important role in the mixture of cadmium, lead, and mercury in the pathogenesis of OLF. Future studies are required to verify our findings and uncover the molecular mechanisms of long-term exposure to a variety of heavy metals, especially cadmium, in other populations, including children, adolescents, and the elderly.

Unique Brain Network Identification Number for Parkinson's and Healthy Individuals Using Structural MRI.

We propose a novel algorithm called Unique Brain Network Identification Number (UBNIN) for encoding the brain networks of individual subjects. To realize this objective, we employed structural MRI on 180 Parkinson's disease (PD) patients and 70 healthy controls (HC) from the National Institute of Mental Health and Neurosciences, India. We parcellated each subject's brain volume and constructed an individual adjacency matrix using the correlation between the gray matter volumes of every pair of regions. The unique code is derived from values representing connections for every node (i), weighted by a factor of 2-(i-1). The numerical representation (UBNIN) was observed to be distinct for each individual brain network, which may also be applied to other neuroimaging modalities. UBNIN ranges observed for PD were 15,360 to 17,768,936,615,460,608, and HC ranges were 12,288 to 17,733,751,438,064,640. This model may be implemented as a neural signature of a person's unique brain connectivity, thereby making it useful for brainprinting applications. Additionally, we segregated the above datasets into five age cohorts: A: ≤32 years (n1 = 4, n2 = 5), B: 33-42 years (n1 = 18, n2 = 14), C: 43-52 years (n1 = 42, n2 = 23), D: 53-62 years (n1 = 69, n2 = 22), and E: ≥63 years (n1 = 46, n2 = 6), where n1 and n2 are the number of individuals in PD and HC, respectively, to study the variation in network topology over age. Sparsity was adopted as the threshold estimate to binarize each age-based correlation matrix. Connectivity metrics were obtained using Brain Connectivity toolbox (Version 2019-03-03)-based MATLAB (R2020a) functions. For each age cohort, a decreasing trend was observed in the mean clustering coefficient with increasing sparsity. Significantly different clustering coefficients were noted in PD between age-cohort B and C (sparsity: 0.63, 0.66), C and E (sparsity: 0.66, 0.69), and in HC between E and B (sparsity: 0.75 and above 0.81), E and C (sparsity above 0.78), E and D (sparsity above 0.84), and C and D (sparsity: 0.9). Our findings suggest network connectivity patterns change with age, indicating network disruption may be due to the underlying neuropathology. Varying clustering coefficients for different cohorts indicate that information transfer between neighboring nodes changes with age. This provides evidence of age-related brain shrinkage and network degeneration. We also discuss limitations and provide an open-access link to software codes and a help file for the entire study.

A technique for the estimation of percolation thresholds in lattice systems: Application to a problem of granular flow through an orifice

A simple method to estimate percolation thresholds pc in lattice models is presented. The technique is based on the calculation of the probabilities RLX(p) for finding a percolating cluster of type X [X could be horizontal (H), vertical (V), average (A), intersection (I), or union (U)] on a finite lattice of side length L at concentration p of occupied sites. The functions RLX(p) are obtained by numerical simulations. Then, (1) effective percolation thresholds pcX,r(L) are estimated from the condition RLX(p)=r (where r is a parameter ranging between 0 and 1); and (2) the percolation threshold in the thermodynamic limit is determined by extrapolating the effective percolation thresholds to infinite L. The methodology presented herein contains and extends the classical scheme developed by Yonezawa, Sakamoto and Hori, offering a more complete and versatile theoretical/simulation framework to calculate percolation thresholds. The approach is validated by successfully comparing with well-known results obtained for the problem of random site percolation on square lattices. Taking advantage of the behavior of the curves of pcX,r(L) for different values of the parameter r, more general scaling relations are proposed for the effective percolation thresholds. Finally, the technique is applied to model experimental data of clogging transitions in a two-dimensional silo with a vibrated base.

Cost-effectiveness analysis of Smart Triage, a data-driven pediatric sepsis triage platform in Eastern Uganda

BackgroundSepsis, characterized by organ dysfunction due to presumed or proven infection, has a case-fatality over 20% in severe cases in low-and-middle income countries. Early diagnosis and treatment have proven benefits, prompting our implementation of Smart Triage at Jinja Regional Referral Hospital in Uganda, a program that expedites treatment through a data-driven triage platform. We conducted a cost-effectiveness analysis of Smart Triage to explore its impact on patients and inform multicenter scale up.MethodsThe parent clinical trial for Smart Triage was pre-post in design, using the proportion of children receiving sepsis treatment within one hour as the primary outcome, a measure linked to mortality benefit in existing literature. We used a decision-analytic model with Monte Carlo simulation to calculate the cost per year-of-life-lost (YLL) averted of Smart Triage from societal, government, and patient perspectives. Healthcare utilization and lost work for seven days post-discharge were translated into costs and productivity losses via secondary linkage data.ResultsIn 2021 United States dollars, Smart Triage requires an annuitized program cost of only $0.05 per child, but results in $15.32 saved per YLL averted. At a willingness-to-pay threshold of only $3 per YLL averted, well below published cost-effectiveness threshold estimates for Uganda, Smart Triage approaches 100% probability of cost-effectiveness over the baseline manual triage system. This cost-effectiveness was observed from societal, government, and patient perspectives. The cost-effectiveness observed was driven by a reduction in admission that, while explainable by an improved triage mechanism, may also be partially attributable to changes in healthcare utilization influenced by the coronavirus pandemic. However, Smart Triage remains cost-effective in sensitivity analyses introducing a penalty factor of up to 50% in the reduction in admission.ConclusionSmart Triage’s ability to both save costs and avert YLLs indicates that patients benefit both economically and clinically, while its high probability of cost-effectiveness strongly supports multicenter scale up. Areas for further research include the incorporation of years lived with disability when sepsis disability weights in low-resource settings become available and analyzing budget impact during multicenter scale up.Trial registrationNCT04304235 (registered on 11/03/2020, clinicaltrials.gov).

METHODOLOGICAL ASPECTS OF INTERSPECIES EXTRAPOLATION OF EXPERIMENTAL DATA UNDER PULSED ACOUSTIC INFLUENCE ON BIOOBJECTS (REVIEW)

Background. Despite a significant number of theoretical and experimental studies, the issue of determining the threshold levels of pulsed acoustic exposure, when exceeded, their negative effect on the morphofunctional state of a biological object begins to appear. Traditionally, in laboratory conditions, such estimates are obtained in experiments on animals, varying the parameters of exposure, followed by extrapolation of the results obtained to humans. However, the pathophysiological mechanisms of disturbances that develop in experimental animals as a result of impulse acoustic impacts have not been sufficiently studied in this context, and indicators of the state of the physiological systems of a biological object that are sensitive to acoustic impulses are not currently taken into account when determining their safe levels.&#x0D; Purpose. The purpose of the work was to analyze the pathophysiological mechanisms of the development of biological effects of pulsed low-intensity acoustic exposure at different levels of the organization of a living system and to develop a methodological approach to obtaining a quantitative assessment and extrapolation of data on such exposure from animals to humans, taking into account the physical parameters of the acoustic factor and characteristics of the state of the experimental biological object.&#x0D; Materials and methods. The selection and systematic review of the scientific literature on the topic of research by keywords in specialized bibliographic databases was carried out.&#x0D; Results. The analysis and generalization of the existing theories about the pathophysiological mechanisms of the biological action of acoustic impulses at different levels of the organization of a living system have been carried out. An original hypothetical scheme for interpreting the effects of acoustic exposure in animals is proposed, which is suitable for obtaining threshold estimates of the levels of the adverse effect of the factor on clinical parameters in experimental animals, and vulnerable critical links in the regulation of external respiration in mammals that cause the damaging effect of acoustic vibrations are identified. A scientific and methodological approach to interspecies extrapolation of medical and biological effects of exposure to low-amplitude air pressure waves from animals to humans has been developed, taking into account the anatomical and physiological parameters of the respiratory system of experimental animals, as well as the informative characteristics of the acoustic pulse. An empirical model is proposed that makes it possible to predict the threshold levels of the conditional power of adverse acoustic effects in humans using data on the development of lung damage in experimental animals of various biological species, and the features of setting up such a model are formulated.&#x0D; Conclusion. It has been substantiated that it is relevant to refine the proposed empirical model and develop a theoretical model for extrapolation of the initial experimental data on the threshold of safe acoustic exposure from animals to humans, taking into account the interspecific patterns of functioning of physiological systems of the body that are critical to the impact.

Applying rainfall threshold estimates and frequency ratio model for landslide hazard assessment in the coastal mountain setting of South Asia

Landslides pose a serious risk to life and property in the mountainous regions around the globe. Understanding the interplay of landslide conditioning and triggering factors is essential for lessening the impacts caused by the hazard. Cox's Bazar — a coastal mountainous district in Bangladesh is recurrently affected by rainfall-triggered landslides. Based on analysis of 14 experiential landslides and combination of gauged and satellite rainfall estimates for the period from 2003 to 2019, the present study determines three landslide-triggering rainfall thresholds for the Cox's Bazar District (CBD): 1. Intensity-Duration (ID) threshold derived in this study revealed that any rainfall event with an intensity of ≥4.04 ​mm/h if prolonging for ≥12h can cause slope failures; 2. Event-Duration (ED) threshold suggested that a normalized cumulative event rainfall (EMAP) of 0.15 for one day is expected to trigger landslides; and 3. threshold calculated using randomly chosen antecedent rainfall expressed best distinction on 30-day rainfall and the equation of the threshold came out as Rth ​= ​64–0.02 Ra30. The recurrence probability of the derived antecedent rainfall threshold and likely landslides was determined through the Poisson distribution. Moreover, we assess the landslide susceptibility of the district with a coupled use of Frequency Ratio (FR) statistical measure and Geographic Information System (GIS). Considering the combined role of selected conditioning factors, the landslide susceptibility status of the CBD was quantified and classified into probability intervals. The accuracy of the susceptibility maps was assessed through the Relative Landslide Density Index (R-Index) that used a field landslide inventory, comprising well distributed 891 events. Moreover, gridded population data was superimposed on the derived susceptibility maps to understand the risk levels of people. The derivation of landslide-triggering rainfall thresholds and spatial susceptibility assessment has been useful to propose a low-cost Landslide Early Warning System (LEWS) which can contribute in alleviating the adverse effects of landslide hazard in the CBD.

A review of experimental task design in psychophysical eye tracking research.

While eye tracking is a technique commonly used in the experimental study of higher-level perceptual processes such as visual search, working memory, reading, and scene exploration, its use for the quantification of basic visual functions (visual acuity, contrast sensitivity, color vision, motion detection) is less explored. The use of eye movement features as dependent variables in a psychophysical investigation can serve multiple roles. They can be central in studies with neurological patients or infants that cannot comply with verbal instructions, understand task demands, and/or emit manual responses. The technique may also serve a complementary role, determining the conditions under which a manual or verbal response is given, such as stimulus position in the visual field, or it can afford the analysis of new dependent variables, such as the time interval between oculomotor and manual responses. Our objective is to review the literature that applied the eye tracking technique to psychophysical problems. The two questions our review raises are: can eye movements (reflex or voluntary) be an objective index of stimulus detection in psychophysical tasks? If so, under what conditions, and how does it compare with traditional paradigms requiring manual responses? Our (non-systematic) methodological review selected studies that used video-oculography as the technique of choice and had a basic visual function as their primary object of investigation. Studies satisfying those criteria were then categorized into four broad classes reflecting their main research interest: (1) stimulus detection and threshold estimation, (2) the effects of stimulus properties on fixational eye movements, (3) the effects of eye movements on perception, and (4) visual field assessment. The reviewed studies support the idea that eye tracking is a valuable technique for the study of basic perceptual processes. We discuss methodological characteristics within each of the proposed classification area, with the objective of informing future task design.