Threshold Estimation Research Articles

Oil rents, renewable energy and the role of financial development: Evidence from OPEC+ members

This study examines the threshold and moderating effects of oil rents on renewable energy consumption in OPEC+ members for different financial development indicators. For this, dynamic panel threshold and GMM estimators are employed for the time period 1999-2019. The empirical findings of the analysis reveal significant and negative threshold and moderating effects for financial market and total financial development, but not for financial institution development. Specifically, oil rents are found to reduce renewable energy consumption, with this negative effect becoming more pronounced at higher levels of financial market and total financial development. Overall, the results do not support the energy transition theory for OPEC+ members for which revenues from oil rents are transferred towards renewable energy investments. Rather, the presence of lobbying influences and inadequate support from financial markets and institutions is validated. These findings provide an additional debating point on the role of oil endowments on sustainable growth.

Development of a Baltimore (MD) population of Calliphora vicina (Diptera: Calliphoridae) reared at several temperatures and estimations of developmental limits and thresholds.

Developmental data for necrophagous Diptera are frequently used in medico-legal investigations to estimate portions of the postmortem interval and interpret periods of insect activity. These applications require baseline developmental data for local populations from geographic locations of interest. For the widely distributed blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae), detailed developmental data does not exist for many locations in the mid-Atlantic region of the United States. This study examined development of C. vicina collected from a large, metropolitan city (Baltimore) in Maryland utilizing 11 ambient temperatures. The developmental threshold and thermal range of growth and tolerance were also estimated, as well as critical thermal minima and maxima based on thermal injury. For this population, linear growth was observed between 10°C and 25°C, whereas flies failed to complete development at temperatures below 7°C or above 28°C. Growth at low temperatures was not curvilinear, which contrasts with other developmental studies using C. vicina and other calliphorids. The lower developmental threshold was estimated to be 5.9°C and corresponds closely with experimental observations. The implications of these result in reference to phenotypic plasticity in populations of C. vicina and applications in forensic entomology are discussed.

Comparison of Click and Level-Specific CE Chirp-Stimulated Auditory Brainstem Responses in Adults with Hearing Loss.

The Claus Elberling Chirp (CE-Chirp) stimulus used in the auditory brainstem responses (ABRs) was developed to compensate for the cochlear wave delay. As a version of broadband CE-Chirp stimulus, the use of level-specific (LS) CE-Chirp stimuli, which are created with varying delay models suitable for the intensity levels at which the sound is transmitted, is becoming increasingly common. The aim of this study was to compare click ABRs with LS CE-Chirp ABR thresholds in adults with sensorineural hearing loss. The research is a cross-sectional, analytical research. Twenty-two adult patients (n = 44 ears) with bilateral sensorineural hearing loss were included in the study. Pure-tone audiometry, click ABR, and LS CE-Chirp ABR tests were performed on adult (13 males and 9 females; 42.86 ± 14.50 years) patients with bilateral sensorineural hearing loss. Click ABR and LS CE-Chirp ABR thresholds were compared in terms of proximity to behavioral hearing thresholds of 2 kHz, 4 kHz, and 2 to 4 kHz averages. Both types of ABR stimuli were able to identify with total hearing loss (n = 6). A significant difference was found between LS CE-Chirp ABR thresholds (53.81 ± 20.28 decibel normal hearing level [dB nHL]) and click ABR thresholds (58.81 ± 19.11 dB nHL) in the other ears (n = 38) with hearing loss (p = 0.00). When both ears were evaluated together and the right and left ears were evaluated separately, no difference was found between LS CE-Chirp ABR thresholds and 4 kHz hearing thresholds (p = 0.66, 0.80, and 0.69, respectively). In adults with hearing loss, the LS CE-Chirp provides ABR thresholds closer to the behavioral hearing thresholds at 2 and 4 kHz compared with the click stimulus. Notably, there was no difference between LS CE-Chirp ABR thresholds and the 4 kHz behavioral hearing thresholds. We concluded that the LS CE-Chirp can be used effectively in the estimation of behavioral hearing thresholds in adults with hearing loss.

Novel empirical curvelet denoising strategy for suppressing mixed noise of microseismic data

We present a novel denoising strategy based on empirical curvelet transform (ECT) for noisy microseismic data. Our approach can simultaneously suppress high-frequency, low-frequency, and shared-bandwidth noises and preserve detailed information on the noisy microseismic data. Initially, we design a new threshold estimation method by adding a scale factor for ECT threshold denoising. Subsequently, we construct an adaptive parameter model employing the similarity standard deviation for the non-local means (NLM) algorithm. Then, we divide the coefficients obtained from the ECT decomposition into two sets based on the energy spectrum, subjecting each set to improved adaptive thresholding and improved NLM denoising algorithms. Eventually, we reconstruct the denoised signals using the empirical curvelet inverse transform. Our results demonstrate that under a signal-to-noise ratio (SNR) of −10 dB, the proposed strategy achieves a correlation coefficient of 0.9524, a root mean square error of 0.198, an SNR of 1.36 dB, and reduces the first arrival picking error to 0.00382 s. Furthermore, application on the real microseismic data further confirms that the proposed method can clarify the corresponding first arrival.

Beyond the threshold: Understanding the asymmetric effects of renewable energy on CO2 emissions

While renewable energy deployment is essential to mitigate climate change, the interplay between renewable energy consumption and environmental degradation may not be linear. The environmental aspect of renewable energy consumption may change over time, depending on the scale and technique effects. This may be due to asymmetry in the relationship. Nonetheless, most current literature either assumes linearity, or ignores the turning point of the behavioral change. This results in inconclusive empirical findings at the disaggregated level of renewable energy consumption. This paper utilizes threshold estimation technique to capture the asymmetry in the renewable energy-CO2 emissions relation in the top ten renewable energy consumers covering the period 1990–2020. The literature gap is addressed by deriving the threshold effect at the aggregate and disaggregated levels to prevent aggregation bias. Understanding the thresholds of different renewable energy sources would improve policy effectiveness and resource allocation at different consumption levels to better curb climate change. The threshold estimation technique measures total renewables, hydro, solar, wind, and others (bioenergy and geothermal) as threshold variables. The findings indicate that total renewables and solar consumptions have stronger mitigating effects on CO2 emissions beyond the consumption levels of 4363.37 and 43.58 kWh, respectively. The advantageous environmental effect of wind consumption only manifests above the consumption level of 657.40 kWh. For policy implication, this study recommends an increase in the weightage of renewables in the energy mix by formulating energy-specific policies, in order to optimize the environmental benefits of renewable energy adoption.

Using heart rate data from wrist worn activity trackers to define thresholds for moderate to vigorous physical activity in children and young people with cystic fibrosis

BackgroundChildren and young people with cystic fibrosis (CYPwCF) are encouraged to do an average of 60 min of moderate-to-vigorous physical activity (MVPA) daily. However, there are no agreed heart rate (HR) thresholds for defining MVPA, so it is difficult to ascertain whether these targets are actually achieved. Wearable activity trackers enable continuous monitoring of fitness-related measures such as HR and could be used to measure duration and intensity of habitual MVPA. We aimed to define personalized and responsive MVPA thresholds from HR in CYPwCF, to determine habitual time spent in MVPA during childhood and adolescence. MethodsContinuous daily HR data were collected from 142 CYPwCF wearing activity trackers over 16 months. Linear mixed-effects models were used to develop personalised estimates of resting heart rate (RHR), peak heart rate (PHR) and MVPA thresholds, which were defined using the American College of Sports Medicine heart rate reserve (HRR) method. Results309,926 days of physical activity data showed that both RHR and PHR declined with age in CYPwCF, with considerable variability within and between individuals. The HRR method produced personalised MVPA thresholds for each CYPwCF based on age, which inherently accounted for individual demographic variability and personal factors such as cardiovascular fitness or disease severity. ConclusionsBy accounting for within and between person variability in RHR and PHR, our novel method provides more accurate age-related personalised MVPA thresholds for CYPwCF than existing estimates. Our findings provide population-based estimates for RHR, PHR and MVPA thresholds at different ages in CYPwCF. This approach may help guide development of international standards for objective MVPA measurement in the era of remote HR and activity monitoring and facilitate accurate measurement of habitual physical activity in children and young people.

Exercise intensity measurement using fractal analysis of heart rate variability: Reliability, agreement and influence of sex and cardiorespiratory fitness

ABSTRACT The study aimed to establish the test-retest reliability of detrended fluctuation analysis of heart rate variability (DFA-α1) based exercise intensity thresholds, assess its agreement with ventilatory- and lactate-derived thresholds and the moderating effect of sex and cardiorespiratory fitness (CRF) on the agreement. Intensity thresholds for thirty-seven participants (17 females) based on blood lactate (LT1/LT2), gas-exchange (VT1/VT2) and DFA-α1 (αTh1/αTh2) were assessed. Heart rate (HR) at αTh1 and αTh2 showed good test-retest reliability (coefficient of variation [CV] < 6%), and moderate to high agreement with LTs (r = 0.40 – 0.57) and VTs (r = 0.61 – 0.66) respectively. Mixed effects models indicated bias magnitude depended on CRF, with DFA-α1 overestimating thresholds versus VTs for lower fitness levels (speed at VT1 <8.5 km⋅hr−1), while underestimating for higher fitness levels (speed at VT2 >15 km⋅hr−1; VO2max >55 mL·kg−1·min−1). Controlling for CRF, sex significantly affected bias magnitude only at first threshold, with males having higher mean bias (+2.41 bpm) than females (−1.26 bpm). DFA-α1 thresholds are practical and reliable intensity measures, however it is unclear if they accurately represent LTs/VTs from the observed limits of agreement and unexplained variance. To optimise DFA-α1 threshold estimation across different populations, bias should be corrected based on sex and CRF.

Reweighted Nadaraya–Watson estimation of stochastic volatility jump-diffusion models

In this paper, we construct the reweighted Nadaraya–Watson estimators of the infinitesimal moments for the volatility process of the stochastic volatility models, with the application of the threshold estimator of the unobserved volatility process. Our model includes jumps in both the underlying asset price and its volatility process. We derive the asymptotic properties of the estimators under the infill and long span assumptions. The results are useful for identification of the process. The finite-sample performance of the estimators is studied through Monte Carlo simulation.

Accuracy of second and third molar maturity indices, Olze, Haavikko, and Demirjian methods for 14- and 16-year-old age thresholds assessment in Croatian children and adolescents.

This study explores the reliability of four established legal age threshold estimation approaches in a Croatian sample. We applied Haavikko stages, Demirjian stages, Olze's third molar eruption stages, and second and third molar maturity indices measurement in 593 orthopantomograms of Croatian children and adolescents aged 11.00-20.99years old. The left mandibular second and third molar were assessed. Logistic regression analysis was conducted to test the significance of predictive variables. Logistic Receiver operating characteristic (ROC) curves were performed to evaluate the classification ability of variables for estimating 14- and 16-year-old thresholds. The areas under the ROC curve (AUC), accuracy (Acc), sensitivity (Se), specificity (Sp), Positive Likelihood Ratio (LR +), Negative Likelihood Ratio (LR-), and Bayes post-test probability (Bayes PTP) were calculated to evaluate classification performance. Results suggest that the combination of I2M&I3M is the best classifier for the 14-year-old threshold (AUC = 0.879); for males alone, I2M is an even better classifier (AUC = 0.881). The highest Acc 80.1% (95%CI, 75.9%-83.9%), Bayes PTP 86.5% (95%CI, 82.8%-89.7%) and Sp 88.9% (95%CI, 83.0%-93.3%) were by I3M < 0.81 & I2M < 0.03 in total samples; the highest Acc 86.1% (80.6%- 90.6%), Bayes PTP 87.2% (95%CI, 81.7%- 91.4%) and Sp 87.8% (95%CI, 78.2%- 94.3%) were by I2M < 0.01 in males, Acc of Haavikko Ac and Demirjian H stage in second molar is very close with slightly lower Bayes PTP and Sp. I3M is a good classifier for 16-year-old threshold (AUC = 0.889). The cut-off value I3M < 0.34 can be used to classify the 16-year-old threshold with Acc of 80.6% (95%CI, 77.2%-83.7%), Sp of 83.4% (95%CI, 79.0%-87.3%), and 81.7% (95%CI, 78.4%-84.8%) Bayes PTP. In conclusion, to classify the 14-year-old threshold, a pair of cut-off values I3M < 0.81 & I2M < 0.03 can be used in Croatian females; I2M < 0.01, Demirjian H stage, Haavikko Ac stage in second molar, and the pair I3M < 0.81 & I2M < 0.03 can all be used in Croatian males. I3M < 0.34 can classify the 16-year-old threshold in Croatian populations.

Inflation Threshold and Financial Sector Development in Uganda

Purpose: This paper empirically analyzes the inflation threshold for better financial sector development (FSD) in Uganda using the yearly trend data spanning over the period 1980 to 2020. The basic idea of the study was to affirm whether the 5-percent bank of Uganda (BOU) inflations rates target is correct. Design/methodology/approach: The analysis incorporates the Autoregressive Distributing Lags (ARDL) model. This is due to the fact that the variables of the study were not all stationary at the same levels but archived strong stationarity after differencing once. To capture the inflation threshold estimation, the Ordinary Least Square model was run with lag value of the dependence variable. Findings: The research indicates that the critical inflation threshold is 6 percent. Below 6 percent inflation, there is a positive and decreasing impact but a statistically insignificant connection between inflation and FSD. Beyond 6 percent, the relationship becomes negative and the intensity increases exponentially as the inflation rate increases. Specifically, the study estimates that at a 5% inflation rate, the FSD has the potential to grow by about 1.3 % and should the inflation rate increase from the optimal of 6% to 7%, it drops by the same magnitude. Research limitations/implications: Data Limitation. The time span of 1980-2020, is because of no data for some variables beyond the chosen time frame. Even if some data were available, some are inconsistence and varies within the available data base set. Originality/value: The study augment to the development of FSD in Uganda by furnishing the Monetary Authority with evidence that help fix the optimal inflation threshold in the country. Similarly, this research will contribute to the existing body of knowledge on how best to manage the inflation rate in the country.

Insurance market development and economic growth in Africa: Contingencies and thresholds of structural transformation

Despite insurance contributions to economic growth, the intervening role of structural transformation on the insurance-growth nexus remains scarce, leaving a gap in the literature. Motivated by the 2030 Sustainable Development Agenda, which envisages higher structural transformation, financial development and economic progress, this study examines the threshold effects and the joint impact of insurance and structural transformation on economic growth in Africa. The study employed the generalised method of moments and dynamic panel threshold estimations on 38 countries covering 2008 to 2020. The following findings emerge: First, insurance and structural transformation promote economic growth. Second, the results indicate that structural transformation enhances the impact of insurance on economic growth. This suggests that structural transformation matters in driving insurance market development, ultimately promoting economic growth. Third, the empirical evidence further reveals nonlinearities in the relationship and presents that a high level of insurance penetration stimulates growth and vice versa. More so, the synergistic effect of insurance and structural transformation on economic growth is more substantial at higher threshold levels. This implies that though insurance spurs economic growth, its impact is more effective through the intervening role of a strong structural transformation. Therefore, this study calls for government intervention and policies to improve structural transformations and form insurance synergies to promote growth.

Longitudinal validity of the Hyperhidrosis Quality of Life Index (HidroQoL©) in a phase IIIb clinical trial population with hyperhidrosis: responsiveness and meaningful change.

The Hyperhidrosis Quality of Life Index (HidroQoL ©) is a well-developed patient-reported outcome measure assessing the quality of life (QoL) impacts in hyperhidrosis, which has proven very good measurement properties, such as structural validity and internal consistency. We aimed to investigate responsiveness over time and estimate values for meaningful within-person change (MWPC) towards symptom improvement for different measurement time points (4 and 12 weeks), extending the existing validity evidence in patients with primary axillary hyperhidrosis. Data (from a phase IIIb clinical trial) was collected at baseline, week 4, week 8, week 12, week 28, week 52, and week 72. For the assessment of responsiveness, HidroQoL change scores were correlated with corresponding change scores of the Hyperhidrosis Disease Severity Scale (HDSS), the Dermatology Life Quality Index (DLQI), and the gravimetric sweat production based on a-priori formulated hypotheses. Furthermore, it was tested whether the different HDSS change score groups differed significantly from each other over time and whether the HidroQoL was sensitive towards these group differences over time. This was extended by the calculation of matched-pair tests and effect sizes to test significance for each change group separately. For the estimation of MWPC thresholds towards symptom improvement, different anchor-based and integrated approaches were used. In total, the sample was composed of 357 patients with primary axillary hyperhidrosis. For the assessment of responsiveness, 5 out of 14 a-priori hypotheses regarding the correlation of the change scores could be confirmed, whereas the rejected hypotheses only marginally differed from the expected values. Furthermore, regarding responsiveness, the HidroQoL showed sensitivity towards symptom improvement at each measurement time point. Effect sizes were large as expected (d ≥ 0.806). MWPC thresholds towards symptom improvement were proposed for two measurement time points: 5 (week 4) and 6 (week 12). Increasing MWPC values over time were observed. This study extends the evidence for the longitudinal validity of the HidroQoL up to 72 weeks and proposed MWPC thresholds for different time intervals (4 and 12 weeks) after baseline, aiding interpretability. Results concur with findings from previous validation studies.

Measurement-Induced Transmon Ionization

Despite the high measurement fidelity that can now be reached, the dispersive qubit readout of circuit quantum electrodynamics is plagued by a loss of its quantum nondemolition character and a decrease in fidelity with increased measurement strength. In this work, we elucidate the nature of this dynamical process, which we refer to as transmon ionization. We develop a comprehensive framework which provides a physical picture of the origin of transmon ionization. This framework consists of three complementary levels of descriptions: a fully quantized transmon-resonator model, a semiclassical model where the resonator is treated as a classical drive on the transmon, and a fully classical model. Crucially, all three approaches preserve the full cosine potential of the transmon and lead to similar predictions. This framework identifies the multiphoton resonances responsible for transmon ionization. It also allows one to efficiently compute numerical estimates of the photon number threshold for ionization, which are in remarkable agreement with recent experimental results. The tools developed within this work are both conceptually and computationally simple, and we expect them to become an integral part of the theoretical underpinning of all circuit QED experiments. Published by the American Physical Society 2024

Development and Validation of a Patient-Reported Outcome Measure of the Impact of Chronic Hand Eczema on Health-Related Quality of Life: the Hand Eczema Impact Scale (HEIS).

Chronic Hand Eczema (CHE) is an inflammatory skin disease that causes significant impact on health-related quality of life (HRQoL). The Hand Eczema Impact Scale (HEIS) is a new patient-reported outcome(PRO) measure designed to assess the impact of CHE on key domains of HRQoL. This study aimed to develop and evaluate content and psychometric validity of the HEIS. The HEIS was initially developed on the basis of a literature review and concept elicitation interviews. Qualitative cognitive debriefing interviews (n = 20) were conducted with patients with CHE to assess relevance and understanding of items, response options, and recall period. Psychometric properties (item performance, dimensionality, reliability, validity, responsiveness, and estimation of meaningful change thresholds) were then assessed using data (n = 258) from a phase 2b trial (NCT03683719). Cognitive debriefing confirmed all items were understood and relevant to patients. Inter-item correlations (all > 0.50) and confirmatory factor analysis (factor loadings ≥ 0.80) supported unidimensionality of the HEIS score, and mostly provided support for the HEIS Proximal Daily Activity Limitations (PDAL) score, with only one item loading below the prespecified threshold. Item properties and previous qualitative work supported retaining this item in the total score but removed from the HEIS PDAL domain. Internal consistency (Cronbach's alpha ≥ 0.89) and test-retest reliability (intra-class correlation coefficient ≥ 0.79) results were very strong. Strong correlations with concurrent measures (0.66-0.87) and significant differences between severity groups (p < 0.001) supported construct validity. Large effect sizes for mean change scores in participants that improved and significant differences between groups indicated ability to detect change. Anchor-based analyses supported within-individual responder definitions of ≥ 1.3 points for improvements in both HEIS score and HEIS PDAL score (covering three items) and of ≥ 1.5 points for HEIS embarrassment with the appearance of hands (Emb) score (covering two items). The 9-item HEIS is the first CHE-specific PROmeasure developed and validated according to regulatory guidance for assessment of the impact of CHE on key domains of HRQoL. This article provides evidence of strong content and psychometric validity and shows improvements of ≥ 1.3 points in HEIS score and HEIS PDAL score, and improvements of ≥ 1.5 points in HEIS Emb score represent clinically meaningful, important changes. NCT03683719.

Accurate optimal quantum error correction thresholds from coherent information

Quantum error correcting (QEC) codes protect quantum information from decoherence as long as error rates fall below critical error thresholds. In general, obtaining thresholds implies simulating the QEC procedure using, in general, suboptimal decoding strategies. In a few cases and for sufficiently simple noise models, optimal decoding of QEC codes can be framed as a phase transition in disordered classical spin models. In both situations, accurate estimation of thresholds demands intensive computational resources. Here we use the coherent information of the mixed state of noisy QEC codes to accurately estimate the associated optimal QEC thresholds already from small-distance codes at moderate computational cost. We show the effectiveness and versatility of our method by applying it first to the topological surface and color code under bit-flip and depolarizing noise. We then extend the coherent information based methodology to phenomenological and quantum circuit level noise settings. For all examples considered, we obtain highly accurate estimates of optimal error thresholds from small, low-distance instances of the codes, in close agreement with threshold values reported in the literature. Our findings establish the coherent information as a reliable competitive tool for the calculation of optimal thresholds of state-of-the-art QEC codes under realistic noise models. Published by the American Physical Society 2024

FibroScan-AST score for diagnosing fibrotic MASH: A systematic review and meta-analysis of diagnostic test accuracy studies.

Following the approval of the first agent for the management of metabolic dysfunction-associated steatohepatitis (MASH), identification of patients with fibrotic MASH (MASH with NAS≥4 and fibrosis stage≥2) is crucial. We assessed the performance of FibroScan-aspartate aminotransferase (AST) score (FAST) for ruling in/out fibrotic MASH. We searched Medline, Cochrane Library, Web of Science, Scopus, and gray literature sources up to January 11, 2024. Studies were eligible if they assessed the accuracy of FAST score for the detection of fibrotic MASH using biopsy as the reference standard at previously reported thresholds (FAST≥0.67 for ruling-in and ≤0.35 for ruling-out fibrotic MASH). We calculated pooled sensitivity and specificity estimates for FAST thresholds alongside 95% confidence intervals following bivariate random- effects models. We assessed the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation framework. We included 16 studies with 8838 participants. A FAST score≥0.67 yielded a pooled specificity of 0.87 (0.82-0.90) while a FAST score≤0.35 yielded a summary sensitivity of 0.88 (0.83-0.91). At a prevalence of 30%, the positive predictive value for ruling-in fibrotic MASH was 60% while the negative predictive value for ruling-out the target condition was 91%. AST levels, cirrhosis prevalence, and number of pathologists reviewing biopsies were sources of heterogeneity among studies. The certainty of evidence was low to very low. FAST score can be used as a triage test for ruling out fibrotic MASH. Nevertheless, its low positive predictive value necessitates sequential testing for ruling-in fibrotic MASH.

Yield Yield loss and economic threshold estimates for pod borer (Helicoverpa armigera) in late maturing pigeonpea (Cajanus cajan)

Pod borer [Helicoverpa armigera (Hubner)] is a major biotic constraint to global pigeonpea production. The farmers largely apply synthetic insecticides to control this pest in pigeonpea. The study was conducted to quantify yield losses and estimate economic thresholds for H. armigera. The late maturing cultivar, IPA-203 was infested with different larval densities to determine the insect density-yield loss relationships. The yield response was variable and grain yield declined with increasing larval density from 1–5/plant. Yield loss of 4.56 kg/ha was evident for each unit increase in larval population. Economic threshold estimates indicated that the control measures for pod borer in IPA 203 cultivar should be initiated at an insect density of ≈1 larva/2 plants or at 3% pod damage to avoid the economic crop losses. The damage potential and economic threshold estimates are prerequisite for integrated pest management and reducing production costs (Alves et al. 2017). Present results indicated that relatively low infestations of H. armigera can cause significant yield reduction in pigeonpea hence intensive monitoring and timely control measures are necessary. Based on present economic threshold estimates, the farmers could decide the timing and kind of control measures to be initiated against pod borer in late pigeonpea cultivars to avert the economic losses.

Enhanced Neonatal Brain Tissue Analysis via Minimum Spanning Tree Segmentation and the Brier Score Coupled Classifier

Automatic assessment of brain regions in an MR image has emerged as a pivotal tool in advancing diagnosis and continual monitoring of neurological disorders through different phases of life. Nevertheless, current solutions often exhibit specificity to particular age groups, thereby constraining their utility in observing brain development from infancy to late adulthood. In our research, we introduce a novel approach for segmenting and classifying neonatal brain images. Our methodology capitalizes on minimum spanning tree (MST) segmentation employing the Manhattan distance, complemented by a shrunken centroid classifier empowered by the Brier score. This fusion enhances the accuracy of tissue classification, effectively addressing the complexities inherent in age-specific segmentation. Moreover, we propose a novel threshold estimation method utilizing the Brier score, further refining the classification process. The proposed approach yields a competitive Dice similarity index of 0.88 and a Jaccard index of 0.95. This approach marks a significant step toward neonatal brain tissue segmentation, showcasing the efficacy of our proposed methodology in comparison to the latest cutting-edge methods.

CyCadas: accelerating interactive annotation and analysis of clustered cytometry data.

Single cell profiling by cytometry has emerged as a key technology in biology, immunology and clinical-translational medicine. The correct annotation, which refers to the identification of clusters as specific cell populations based on their marker expression, of clustered high-dimensional cytometry data, is a critical step of the analysis. Its accuracy determines the correct interpretation of the biological data. Despite the progress in various clustering algorithms, the annotation of clustered data still remains a manual, time consuming and error-prone task. We developed a user-friendly cluster annotation and differential abundance detection tool that can be applied on data generated with Self Organizing Map clustering algorithms, thus simplifying the annotation process of datasets that consist of hundreds or thousands of clusters. We present Cytometry Cluster Annotation and Differential Abundance Suite (CyCadas), a semi-automated software tool that facilitates cluster annotation in cytometry data by offering both visual and computational guidance. CyCadas addresses the critical need for efficient and accurate annotation of high-resolution clustered cytometry data, significantly reducing the time needed to perform the analysis compared to both manual gating approaches and manual annotation of clustered data. The tool features a user-friendly interface, visual tools enabling data exploration and automated threshold estimation to separate negative and positive marker expression. It facilitates the definition and annotation of cell phenotypes among multiple clusters in a tree-based data structure. Finally, it calculates the abundance of various cell populations across the conditions with statistical interpretation. It is an ideal resource for researchers aiming to streamline their cytometry workflow. CyCadas is available as open source at: https://github.com/DII-LIH-Luxembourg/cycadas.

Pressure and cold pain threshold reference values in a pain-free older adult population.

More sex-specific pain sensitivity normative values from population-based cohorts in pain-free older adults are required. The aims of this study were (1) to provide sex- and age-specific normative values of pressure and cold pain thresholds in older pain-free adults and (2) to examine the association of potential correlates of pain sensitivity with pain threshold values. This study investigated sex-specific pressure (lumbar spine, tibialis anterior, neck and dorsal wrist) and cold (dorsal wrist) pain threshold estimates for older pain-free adults aged 41-70years. This cross-sectional study used participants (n = 212) from the Raine Study Gen1-26year follow-up. The association of pain thresholds, with correlates including sex, test site, ethnicity, waist-hip ratio, smoking status, health-related quality of life, depression, anxiety and stress symptoms, sleep quality, socioeconomic status and physical activity levels, was examined. Values for pressure and cold pain thresholds for older pain-free adults are provided, grouped by vicennium, sex and test site (pressure). Statistically significant independent correlates of increased pressure pain sensitivity were test site, ethnicity and sex. Only lower waist/hip ratio was a statistically significant, independent correlate of increased cold pain sensitivity. This study provides robust sex- and age-specific normative values for pressure pain threshold and cold pain threshold for an older adult pain-free population. Combined with existing values, these data provide an important resource in assisting interpretation of pain sensitivity in clinical pain disorders and provide insights into the complex association of pain sensitivity with correlates that can be used in research.