Changes In Variability Research Articles

Cross-Sectional Study Evaluating the Role of Autonomic Nervous System Functional Diagnostics in Differentiating Post-Infectious Syndromes: Post-COVID Syndrome, Chronic Fatigue Syndrome, and Lyme Disease

Background/Objectives: Post-infectious syndromes, including Post-COVID syndrome, Chronic Fatigue Syndrome, and late-stage Lyme disease, are associated with overlapping clinical features and autonomic dysfunction. Despite shared symptoms such as fatigue and orthostatic intolerance, the underlying pathophysiology and specific patterns of autonomic dysfunction may differ. This study aimed to evaluate and compare autonomic nervous system function in these syndromes using multiple diagnostic modalities to identify unique characteristics and improve differentiation between these conditions. Methods: This cross-sectional study included 758 patients, which were divided into four groups: Post-COVID syndrome, Chronic Fatigue Syndrome following Post-COVID syndrome, Chronic Fatigue Syndrome unrelated to COVID-19, and late-stage Lyme disease. Autonomic nervous system function was assessed using cardiovascular reflex tests, the Head-Up Tilt Test, beat-to-beat analysis, five-minute electrocardiogram recordings, 24 h Holter electrocardiogram monitoring, and 24 h ambulatory blood pressure monitoring. Statistical analyses compared parameters across the groups, focusing on patterns of sympathetic and parasympathetic dysfunction. Results: The patients with Lyme disease showed distinct autonomic patterns, including a higher prevalence of orthostatic hypotension (53.4%) and changes in heart rate variability during the Head-Up Tilt Test suggestive of adrenergic failure. Compared to the other groups, patients with Lyme disease exhibited reduced baroreceptor sensitivity and diminished changes in frequency domain heart rate variability parameters during orthostatic stress. Parasympathetic dysfunction was less prevalent in the Lyme disease group, while the Post-COVID syndrome and Chronic Fatigue Syndrome groups showed more pronounced autonomic imbalances. Conclusions: The patients with Post-COVID syndrome, Chronic Fatigue Syndrome, and late-stage Lyme disease exhibited varying degrees and types of autonomic dysfunction. Late-stage Lyme disease is characterized by adrenergic failure and distinct hemodynamic responses, differentiating it from other syndromes. The functional assessment of autonomic nervous system function could aid in understanding and managing these conditions, offering insights for targeted therapeutic interventions.

Effect of 40 continuous connected breathing on electroencephalogram and heart rate variability of healthy volunteers

Objectives: Continuous connected breathing (CCB) is a high-frequency breathing technique without breath retention. This study examines changes in electroencephalogram (EEG) band power and heart rate variability (HRV) before, during and after breathwork intervention of 3 rounds of 40 CCB versus normal breathing in healthy volunteers. Materials and Methods: Thirty-three healthy volunteers, aged between 19 and 23 years, participated in the study (n = 15; female = 7; mean age = 21.5 years) group, while the control group consisted of 18 individuals (n = 18; male = 11; mean age = 19.6 years). After acquiring baseline measures, the study group engaged in 40 CCB practice online for 10 days, while the control group continued with their usual activities. EEG and HRV signals were recorded for both groups after the 10 days. Post-intervention, the study group practised 40 CCB breathwork, while the control group breathed normally during signal acquisition. EEG was recorded for 1-min durations at five different time events (1st, 4th, 5th, 7th and 10th min) according to the protocol. HRV was continuously recorded for the entire 10 min, and 1-min readings corresponding to the EEG recording time intervals were analysed. EEG signals were acquired using an Enobio-8 cap with dry electrodes in pre-frontal (FP1 and FP2), temporal (T7 and T8), central (C3 and C4) and occipital (O1 and O2) regions. HRV data were acquired from Polar H7/H10 chest strap sensors through Bluetooth using Elite HRV app on android phone and data were later processed with Kubios software. EEG signals were processed using MATLAB software to extract EEG power for delta (0– 3.5Hz), theta (4–7 Hz), alpha (8–13 Hz), beta (14–29 Hz) and gamma frequencies (30–50 Hz). The EEG power and HRV signals were later arranged as before-after and during time events and statistically analysed for within and between-group changes using t-tests for significance of means. Results: There was an overall quantitative change in EEG band power of −2 units within the study group and −0.03 within the control group. A significant decrease was found in overall delta (−2.27), theta (−1.7), alpha (−1.8) and beta (−2.27) brain waves in pre-frontal (FP1, FP8), temporal (T7, T8) and occipital (O1, O2) regions after breathwork compared to before within the study group. A significant increase was found in beta (+2.8) band power in the control group with a higher increase in the left compared to the right hemisphere. Bilateral average change ranged from −1.6 to −2.6 in the study and −0.1 to +4.9 in the control group. HRV parameters were reduced after intervention in both groups but without significance. The parameters improved after the intervention compared to during within the study group, though not significant. Conclusion: 10 days of practice of 40 CCB breathworks (3 rounds) for 5 min/day may reduce EEG power in delta, theta, alpha and beta waves. It may help to maintain autonomic balance with an increase of HRV in the recovery phase after an initial decrease during breathwork. Further studies are recommended to test the consistency of outcomes.

External trigeminal nerve stimulation (eTNS) Exhibits relaxation effects in fatigue states following napping deprivation.

In the face of inevitable declines in alertness and fatigue resulting from sleep deprivation, effective countermeasures are essential for maintaining performance. External trigeminal nerve stimulation (eTNS) presents a potential avenue for regulating alertness by activating the locus coeruleus and reticular activating system. Here, we conducted a within-subject study with 66 habitual nappers, subjecting them to afternoon nap-deprivation and applying either 20-minute of 120Hz eTNS or sham stimulation. We compared participants' performance in PVT and N-back tasks, subjective fatigue level and alertness ratings, and changes in heart rate variability, cortisol, and salivary alpha-amylase before and after stimulation. The results revealed a significant decline in PVT and N-back tasks performance, along with increased subjective fatigue levels in the sham stimulation group. In contrast, the eTNS stimulation group maintained behavioral performance, with lower post-stimulation fatigue levels than sham group. After stimulation, the eTNS group exhibited decreased mean R-R interval and elevated LF/HF ratios, i.e., a shift in autonomic nervous system activity towards sympathetic dominance, and a significant reduction in cortisol levels, indicating a state of relaxation alleviating drowsiness. These findings suggested that 120Hz eTNS stimulation might induce a relaxing effect, and thereby alleviate fatigue while preserving alertness and cognitive performance.

Abstract TP382: Genome-wide DNA Methylation Profiling Reveals Low Methylation Variability in Moyamoya Disease

Background: Moyamoya disease (MMD) is a chronic cerebrovascular disorder that can affect both children and adults. It is characterized by chronic and progressive narrowing of the cerebral arteries and the formation of fragile collateral blood vessels. The narrowed arteries can lead to lead to stroke and neurological dysfunctions. Considering that MMD is mostly sporadic and gene-environment interactions play an important in various diseases, we sought to investigate epigenetic modifications in MMD, focusing specifically on changes in DNA methylation magnitude and variability. Methods: We performed genome-wide DNA methylation using Illumina 850K Methylation EPIC BeadChip, in two racially distinct adult female cohorts: A Non-Asian cohort (13 MMD patients and 7 healthy controls) and an Asian cohort (14 MMD patients and 3 healthy controls). An additional external cohort with both sexes (females: 5 MMD patients and 5 healthy controls, males: 5 MMD patients and 5 healthy controls) was included for validation. Results: Our findings revealed subtle changes in the magnitude of DNA methylation, but a strikingly low DNA methylation variability between MMD patients and healthy controls across both female MMD cohorts. In the Non-Asian cohort, only 6 probes showed increased variability, compared to 647 probes that showed decreased variability. Similarly, in the Asian cohort, the MMD group also displayed a reduced methylation variability across all 2845 probes. Further analysis showed that these differentially variable probes are associated with genes involved in key biological processes such as methylation and transcription, DNA repair, cytoskeletal remodeling, natural killer cell signaling, cellular growth, and migration. Conclusions: These findings mark the first observation of low methylation variability in any disease, contrasting with the high variability observed in other disorders. This reduced methylation variability in MMD may impair patients’ adaptability to environmental changes, such as hemodynamic stress, thereby disrupting vascular homeostasis and contributing to MMD pathology. These findings offer new insights into the mechanisms of MMD and suggest potential avenues for treatment strategies.

Historical Review of Research on Fisheries vs. Climate Changes and Proposals for the Future in a Global Warming Context

Marine environmental variability and climate change are interconnected; they are the main causes of the fluctuations in ecosystems and cyclically affect fisheries. This work has four main goals. The first is to present a broad historical review of international research activities on fisheries and climate change, mainly in European waters. We have recovered a selection of seminal international scientific publications from 1914 to 1995, which aroused great interest among the scientific community at that time, although most of these publications have fallen into oblivion in the 21st century. The second goal is to review the main intergovernmental initiatives on climate and marine research from the 1980s to the present, detecting gaps and a lack of unanimity in some guidelines from international organizations. The third goal is to analyze decadal warming/cooling in the Canary Current Upwelling System (extending from the NW Iberian Peninsula to Senegal), to understand the current rapid tropicalization of pelagic and benthic ecosystems in Southern European Atlantic seas. The fourth goal is to identify priority research lines for the future, including the need to promote an international retrospective on fisheries oceanography research, for at least the last hundred years.

The acute effect of bitemporal electroconvulsive therapy on synchronous changes in heart rate variability and heart rate in patients with depression

Objective.The transient autonomic nervous system responses induced by electroconvulsive therapy (ECT) may serve as critical indicators of treatment efficacy and potential side effects; however, their precise characteristics remains unclear. Considering that the intense stimulation of ECT may disrupt the typical antagonistic relationship between the sympathetic and parasympathetic branches, this study aims to conduct a meticulous analysis of the rapid changes in heart rate variability (HRV) and HR during ECT, with a particular focus on their synchronized interplay.Methods.Pulse interval sequences were collected from 50 sessions of bitemporal ECT administered to 27 patients diagnosed with major depressive disorder. The average HR and ultra-short term HRV indices RMSSD and SDNN, as well as the Poincaré indices SD1, SD2 and SD2/SD1, were calculated using a 10 s sliding window with a step size of 1 s. In particular, the synchronous changes between SD1, SD2, SD2/SD1 and HR were analyzed.Results.The synchronous changes of the indices showed different characteristics over time. In particular, SD1, SD2 and HR increased significantly by 41.50 ± 11.45 ms, 33.97 ± 10.98 ms and 9.68 ± 2.00 bpm respectively between 8 and 20 s, whereas they decreased significantly by 19.89 ± 9.07 ms, 17.54 ± 8.54 ms and 3.80 ± 1.33 bpm respectively between 45 and 53 s after ECT stimulus onset. SD1 and SD2 both had highly significant positive correlations with HR in the above phases.Conclusion.The results suggest that bitemporal ECT induces the sympathetic and parasympathetic co-activation during the early ictal period and brief co-inhibition approximately 45 s after stimulus. Our findings may provide new insights comprehending the mechanisms of ECT and its associated cardiovascular risks.

Evaluation of aerosol loading and its relationship with geopotential height in Nigeria’s Guinea Coast

Climate variability and atmospheric changes significantly affect weather patterns and human activities. Aerosols impact the Earth's climate by influencing cloud formation, scattering radiation, and cooling the planet. However, aerosols, like black carbon, absorb and reemit radiation, contributing to global warming. This study aims to assess aerosol optical depth (AOD) over Nigeria's Guinea Coast, compare aerosol loading across the region, examine the relationship between aerosol loading and geopotential height, and explore the impact of meteorological variables on aerosol levels. AOD data were sourced from MODIS, while geopotential height and meteorological data was obtained from MERRA-2. The study found significant aerosol loading during the dry season, particularly along the coastal region (Lagos, Warri, and Port Harcourt), and lower AOD during the wet season. Geopotential height values were higher during the wet season, especially at 1000-hPa and 850-hPa. A positive correlation was found between AOD and geopotential height. Wind speeds were higher in the north and along the coast, with specific humidity at 1000-hPa directly correlating with geopotential height and inversely with wind speed. The study also showed that the annual AOD distribution mirrors geopotential height patterns at 1000-hPa, with higher values in southern Nigeria. In conclusion, aerosol loading is higher during the dry season, particularly in coastal regions and at lower atmospheric levels. The study highlights how seasonal changes and geographical factors influence aerosol distribution. It also shows that geopotential height strongly affects aerosol concentration, with higher heights linked to increased AOD. This underscores the importance of surface-level aerosols for human health, agriculture, and visibility, and suggests that geopotential height influences where aerosol loading is highest.

Precipitation variability in CMIP6 climate models across the North Atlantic–European region and their Links to Atmospheric Circulation

Long-term changes in climate variability represent an important aspect of climate change, with various impacts on society and environment. In this study, we analyze outputs from 13 CMIP6 global climate models (GCMs) across the North Atlantic–European domain, focusing on their simulations of precipitation probability and short-term variability in both historical and future climates. Precipitation probability denotes the probability of a wet day (> 1 mm), and precipitation variability reflects the tendency to cluster wet days into sequences. By comparing against the ERA5 reanalysis, we found that the GCMs tend to overestimate precipitation probability across Europe in winter, whereas in summer, they have a tendency to underestimate it around 50°N. Precipitation variability is, on average, underestimated by the GCMs in summer, while overestimated in several regions in winter. Projections for the end of the twenty-first century indicate significant changes in both precipitation probability and variability which are more pronounced under the more pessimistic emission scenario compared to the moderate one. We found that the changes in probability and variability are mutually independent: the former being more latitudinal-dependent while the latter differs between the west and east. After identifying atmospheric circulation conducive and non-conducive to precipitation occurrence, we found that GCMs overestimating the frequency of conducive circulation tend to overestimate precipitation probability, and vice versa. Furthermore, increased precipitation variability is associated with higher circulation variability. Finally, our analysis reveals that projected changes in precipitation probability and variability are often linked to projected changes in atmospheric circulation, especially in winter.

Analysis of vulnerability, its drivers, and strategies applied towards reducing the pastoral and agro-pastoral livelihood vulnerability to climatic shocks

In recent decades, the global climate has changed mainly due to human-induced causes and realizing their manifestations in the forms of extreme events such as droughts, floods, heat stress, and variability in rainfall. Arid and semi-arid ecosystems are sensitive to changes in climate variability, including the Borana zone. This study was therefore initiated to assess how vulnerable pastoral and agro-pastoral livelihoods are to climate change, as well as to estimate the effects, and pinpoint potential response measures that could be implemented in the study area. Data were gathered by surveys, focused group and expert group discussions. The quantitative data were analyzed through descriptive and inferential statistics, while the qualitative data was analyzed using thematically organized content analysis. The findings indicate that there is high degree of climatic risk to the livelihoods of both pastoralists and agro-pastoralists (− 0.37). The ability of pastoralists to adapt in comparison to agro-pastoralists is largely determined by numbers of factors, including inadequate livelihood strategies, poor access to social safety networks and services, knowledge and communication gaps, and availability of water resources. The area was extremely susceptible to the effects of climate change, which led to disaster. The primary outcome, which also affects other sources of income, is the loss of livestock (97%) which is followed by food shortages (91%), decreased income (84%), feed scarcity (83%), water scarcity (80%), and crop failure (79%). Managing livestock, taking advantage of social capital, storing hay and crop residue, and destocking animals during the period of severe drought were the main strategies used to reduce the vulnerability and enhance the adaptive capacity. Furthermore, despite the government’s numerous efforts to lesson enduring vulnerabilities and their effects, progress has not been encouraging because of lack of proactive action when faced with emergences. Hence, in order to decrease vulnerability and increase adaptive capacity, policymakers and development practitioners should collaborate proactively and develop area-specific adaptation strategies. These might include income diversification, increased access to water and pasture; installation of easily accessible market channels; and establishment of early warning systems that assist community preparation and resilience.

Simulating the Influence of Rainfall Variability on Discharge in the Upper River Yala Basin, Kenya

Climate variability is significantly altering river flows globally, increasing the risk of floods and droughts. Projections indicate both rising and declining flows across various regions, influenced by the impacts of climate variability and land use changes. Research has shown that climate change, land use, and pollution exacerbate water scarcity for half the global population, impacting ecosystems, especially in vulnerable regions. This study focuses on the Upper Yala River in Kenya, exploring climate variability's influence on discharge in various Land Use contexts using the SWAT model. Existing research highlights the significance of land use, hydrological indicators, and climate data, establishing a framework to analyze stream flow trends. The study analyzed climate and stream flow data from 1990-2020 using the SWAT model for hydrological assessment and predictions for the years 2024 to 2040 was done. The research was guided by Water Balance Theory and employed a descriptive and analytical design. Data collection included meteorological data from weather stations, hydrological data from gauging stations, and land use and land cover (LULC) data from remote sensing and satellite imagery. The Soil and Water Assessment Tool (SWAT) was used to simulate river discharge and assess the impacts of climate variability, integrating climate, land use, soil type, and topographic data. Data analysis involved descriptive statistics to summarize discharge data, correlation analysis to link rainfall variability and discharge patterns, and performance metrics like the Nash-Sutcliffe Efficiency (NSE) and Coefficient of Determination (R²) to validate the model. Statistical techniques identified long-term trends in climate and streamflow, focusing on inter-seasonal and inter-annual variations. The Upper Yala River Basin experiences significant inter-seasonal and inter-annual streamflow variations, primarily influenced by rainfall fluctuations. A strong correlation between simulated and observed discharge data for the Upper Yala River Basin was demonstrated. The mean observed discharge was 48.69 m³/s, with maximum and minimum values of 163.09 m³/s and 0.328 m³/s, and a standard deviation of 34.28 m³/s. In contrast, the simulated discharge had a mean of 53.56 m³/s, with maximum and minimum values of 174.41 m³/s and 0.360 m³/s, and a standard deviation of 37.87 m³/s. The minimal differences between the observed and simulated values underscore the model's effectiveness in accurately reflecting the impacts of rainfall variability on river flow dynamics. The study concluded that in the Upper River Yala watershed, rainfall variability accounted for 94.2% of the variations in river discharge quantity. The study recommends enhancing climate monitoring by adding weather stations and stream gauges in the basin and utilizing remote sensing for tracking land use and vegetation changes. Improved data availability from these measures will enable better discharge predictions and inform water management decisions to mitigate climate impacts on the river basin and surrounding communities.

Mapping Trajectories of Gait Recovery in Clinical Stroke Rehabilitation.

How gait changes during the early stages of stoke rehabilitation, and which patient characteristics are associated with these changes is still largely unknown. he first objective was to describe the changes in gait during stroke rehabilitation. Secondly, we determined how various patient characteristics were associated with the rate of change of gait over time. Participants were measured every 3 weeks during stroke rehabilitation. The assessment consisted of an inertial measurement unit (IMU) based 2-minute walk test (2MWT), 3 IMU-based balance tests, and standard clinical tests. In the 2MWT, participants were equipped with 3 IMUs, from which speed, variability, asymmetry, and smoothness were calculated. The changes in gait were examined from admission to discharge at an individual level. The effect of patient characteristics on the rate of change of the gait features over time was assessed with growth models. A total of 81 Trajectories from 72 participants were analyzed. On an individual basis, speed increased in 32 trajectories. Only a few trajectories exhibited significant changes in variability, asymmetry, and smoothness over the clinical rehabilitation period. The growth models revealed a significant increase in speed and decrease in variability and smoothness. Only the Berg Balance Scale and gait speed at onset were (negatively) associated with the rates of change of speed and smoothness, respectively. We found a substantial variability in the gait-feature outcomes and their progression in individuals after stroke during clinical rehabilitation. The patient characteristics studied had limited associations with the rate of change of gait features over time.

Understanding tinnitus symptom dynamics and clinical improvement through intensive longitudinal data

Intensive longitudinal sampling enhances subjective data collection by capturing real-time, dynamic inputs in natural settings, complementing traditional methods. This study evaluates the feasibility of using daily self-reported app data to assess clinical improvement among tinnitus patients undergoing treatment. App data from a multi-center randomized clinical trial were analysed using time-series feature extraction and nested cross-validated ordinal regression with elastic net regulation to predict clinical improvement based on the Clinical Global Impression—Improvement scale (CGI-I). With 50% app compliance (N = 129, 8480 entries), the model demonstrated good fit to the test data (McFadden R2 = 0.82) suggesting its generalizability. Clinical improvement was associated with linear declines in tinnitus-related thoughts, jaw tension, tinnitus loudness, increases in happiness, and variability changes in tinnitus loudness and distress. These findings suggest that daily self-reported data on tinnitus symptoms is sensitive to treatment response and provides insights into specific symptom changes that occur during treatment.

Biomechanical coordination and variability alters following repetitive movement fatigue in overhead athletes with painful shoulder

Most sports and leisure activities involve repetitive movements in the upper limb, which are typically linked to pain and discomfort in the neck and shoulder area. Movement variability is generally expressed by changes in movement parameters from one movement to another and is a time-dependent feature of repetitive activities. The purpose of this study was to examine the effect of repeated movement-induced fatigue on biomechanical coordination and variability in athletes with and without chronic shoulder pain (CSP). In this controlled laboratory study, 24 overhead athletes in two groups of athletes with (N = 12) and without (N = 12) CSP were recruited. Biomechanical and Electromyographical data were recorded while the athletes were asked to perform repeating reaching tasks (RRT). Kinematic data was recorded every 30 s of the minutes of the repetitive pointing task (RPT). The kinematic and electromyography data were recorded at the first 30 s of “Fatigue-Terminal” (FT) and the last 30 s of “No-Fatigue” (NF) in the repetitive pointing task (RPT). Raw data was analyzed by using MATLAB code to extract the relevant coordination and movement variability data. Different fatigue conditions led to significant kinematic changes during the repetitive pointing task. In the CSP group, trunk lateral flexion decreased after fatigue, while it increased in the CON group (p < 0.013). Trunk rotation and shoulder elevation angles were smaller before fatigue than after in both groups (p < 0.001). Variability in joint angles, including trunk lateral flexion and elbow flexion, increased after fatigue, indicating less stability in movement patterns (p < 0.001). The coordination between trunk movement and shoulder elevation was altered post-fatigue, with significant changes in EMG variability for muscles like the Lower Trapezius and Long Head of the Biceps (p < 0.001). Results of our study indicate that both groups were able to accomplish fatigue, but they employed different movement strategies. The CSP group primarily focused on controlling the shoulder joint, while the CON group utilized both the shoulder and elbow joints in their strategy. This difference suggests that individuals in the CSP group who experienced chronic pain may have developed a strategy to minimize pain and fatigue during the task. Specifically, the CSP group’s approach appeared to involve adjustments in movement patterns to manage the task despite fatigue. This adaptation contrasts with the CON group’s more complex movement strategy, which involved greater variability and adjustments in both the shoulder and elbow joints.

Analysis of spatiotemporal distribution, variability, and trends of rainfall in Wollo area, Northeastern Ethiopia.

Ethiopia's agriculture is mostly dependent on rain, though the rainfall distribution and amount are varied in spatiotemporal context. The study was conducted to analyze the distribution, trends, and variability of monthly, seasonal, and annual rainfall data over the Wollo area from 1981 to 2022. To accomplish this, the study utilized the Climate Hazards Group Infrared Precipitation with Stations version two (CHIRPS-v2) data. Standard Rainfall Anomaly Index (SRA) and Coefficient of Variation (CV) were employed to examine rainfall variability and develop drought indices over southern Ethiopia. The Modified Mann Kendall (MMK) test, Sen's slope estimator and the innovative trend analysis (ITA) were employed to detect temporal changes in rainfall trends over the study period. The study found that the area experienced considerable rainfall variability and change, resulting in extended drought and flood events within the study period. Results from SRA and CV revealed interannual and seasonal rainfall variability, with the proportions of years below and above the long-term mean being estimated at 56% and 44%, respectively. The MMK test showed that the annual rainfall during the Kiremt (summer-main rainy season) had an increasing trend. On the other hand, rainfall for the Belg (short rain season for the study area) season and the Bega (winter) season showed a significantly decreasing trend (p < 0.05). Results from the innovative trend analysis (ITA) also revealed that the annual and seasonal rainfall trends exhibited different trends in varied magnitude for different stations. On a spatial basis, the eastern and northeastern regions of the study area showed trends of increasing rainfall during the Kiremt (JJA). Decision-makers and development planners need to design strategies to mitigate the risks posed by changes in rainfall variability and distribution and enhance community adaptation and mitigation capacities in Wollo, Ethiopia.

Analysis of heart rate as a predictor of changes in heart rate variability in children.

To evaluate the predictive validity and cut-off point of heart rate and blood pressure on heart rate variability (HRV) changes in children with and without obesity. This study included 125 children, of whom 41 were normal weight and 84 were obese. Anthropometry, blood pressure, heart rate, and HRV were measured using an electronic scale and stadiometer, a sphygmomanometer, and HRV monitor. In addition, the receiver operating characteristic (ROC) curve was obtained by statistical analysis of the data. Heart rate proved to be a good predictor for changes in the square root of the mean of the square of the differences between consecutive NN intervals (RMSSD) parameter in students of both sexes for the normal-weight group (ROC 0.89; 95%CI 0.77-1.00) and obesity (ROC 0.90; 95%CI 0.83-0.97). In addition, the heart rate cut-off point for alterations in the RMSSD parameter for normal-weight boys was 93 bpm (sensitivity 100.00% and specificity 87.50%) and for boys with obesity, the established cut-off point was 91 bpm (sensitivity 94.74% and specificity 63.64%). Heart rate also proved to be a good predictor considering low-frequency/high-frequency ratio (LF/HF) and standard deviation of long-term continuous NN intervals /standard deviation of the instantaneous variability of continuous NN intervals in the Poincaré graph ratio (SD2/SD1). Systolic and diastolic blood pressures were good predictors in more specific stratifications and, therefore, can be used in some cases. The predictive validity of heart rate was shown to be at a good level, with high sensitivity and acceptable specificity for the cut-off points according to the different analyses stratified by gender and nutritional status. In this sense, health professionals will be able to use heart rate to estimate cardiovascular risk in children of different sexes and nutritional status.

Functional characterization of eQTLs and asthma risk loci with scATAC-seq across immune cell types and contexts.

cis-regulatory elements (CREs) control gene transcription dynamics across cell types and in response to the environment. In asthma, multiple immune cell types play an important role in the inflammatory process. Genetic variants in CREs can also affect gene expression response dynamics and contribute to asthma risk. However, the regulatory mechanisms underlying control of transcriptional dynamics across different environmental contexts and cell types at single-cell resolution remain to be elucidated. To resolve this question, we performed single-cell ATAC-seq (scATAC-seq) in peripheral blood mononuclear cells (PBMCs) from 16 children with asthma. PBMCs were activated with phytohemagglutinin (PHA) or lipopolysaccharide (LPS) and treated with dexamethasone (DEX), an anti-inflammatory glucocorticoid. We analyzed changes in chromatin accessibility, measured transcription factor motif activity, and identified treatment- and cell-type-specific transcription factors that drive changes in both gene expression mean and variability. We observed a strong positive linear dependence between motif response and their target gene expression changes but a negative relationship with changes in target gene expression variability. This result suggests that an increase of transcription factor binding tightens the variability of gene expression around the mean. We then annotated genetic variants in chromatin accessibility peaks and response motifs, followed by computational fine-mapping of expression quantitative trait loci (eQTL) from a pediatric asthma cohort. We found that eQTLs were 5-fold enriched in peaks with response motifs and refined the credible set for 410 asthma risk genes, with 191 having the causal variant in response motifs. In conclusion, scATAC-seq enhances the understanding of molecular mechanisms for asthma risk variants mediated by gene expression.

The time-course changes in postural control variability between neck pain and asymptomatic dental students

Changes in postural control associated with clinical practice or specific conditions such as the presence of neck pain remain unexplored in dental students. Therefore, this study aimed to explore the time-course changes in postural control complexity among dental students enrolled in clinical practice, comparing those with and without neck pain. We used an online Nordic Musculoskeletal Questionnaire for group allocation and center of pressure (CoP) oscillations with a tri-axial Bertec force plate. Baseline data were acquired from dental students with neck pain (NP) (n = 21) and asymptomatic in a control group (n = 23), before starting their clinical practice, and assessments were repeated after their first semester. CoP fluctuations were determined through the calculation of sample entropy. Both groups had similar postural control at baseline, but asymptomatic students exhibited more irregular CoP AP (p = 0.013) and ML (p = 0.015) oscillations, while students with neck pain showed a more rigid pattern (p = 0.004) in the AP direction at the endpoint. Our results showed that dental students’ postural control complexity decreased during the first semester of clinical practice. Over time, asymptomatic students exhibited more random postural control patterns, while students with neck pain demonstrated more rigid postural control during upright stance, indicating that postural control complexity differs between students with and without neck pain when exposed to clinical training.

Changes in heart rate variability at rest and during exercise in patients after a stroke: a feasibility study

The aim of this study was to evaluate the feasibility of using a biofeedback-enhanced robotics-assisted tilt table (RATT) to investigate time- and intensity-dependent changes in heart rate variability (HRV) at rest and during heart rate-controlled exercise in patients recovering from a stroke. Twelve patients (age 55.3 years ± 15.6 years, 7 women) completed two separate measurement sessions. The first involved familiarization and system identification to determine parameters of a feedback system for automatic control of heart rate (HR). The second comprised 14 min of rest and 21 min of active exercise during which HR was held constant using feedback control to eliminate cardiovascular drift. HR data were collected using a chest-belt HR sensor, and raw RR intervals were employed for HRV analysis during periods of rest (0–7 min and 7–14 min) and exercise (5–13 min and 13–21 min). A biofeedback-enhanced, robotics-assisted tilt table can be successfully employed to perform heart rate-controlled exercises in patients after a stroke. All HRV metrics were substantially lower during exercise compared to rest. In the rest period, HRV values during 0–7 min were lower than during 7–14 min, in line with a slight HR decrease over the entire rest period. During exercise, HRV values during 5–13 min were higher than during 13–21 min, suggesting a time-dependent HRV decrease. All HRV metrics exhibited intensity- and time-dependent changes: higher HRV at rest and decreasing HRV over time. Understanding these HRV characteristics will support the development of heart rate-controlled exercise regimens and protocols for examining HRV changes during exercise in patients.

Monitoring Environmental Degradation and Spatial Changes in Vegetation and Water Resources in the Brazilian Pantanal

Diagnosing climate variability and environmental change in floodable regions is essential for understanding and mitigating impacts on natural ecosystems. Our objective was to characterize environmental degradation in the Brazilian Pantanal by identifying changes in vegetation and water cover over a 30-year period using remote sensing techniques. We evaluated surface physical–hydric parameters, including Land Use and Land Cover (LULC) maps, Normalized Difference Vegetation Index (NDVI), Modified Normalized Difference Water Index (MNDWI), Normalized Difference Moisture Index (NDMI), and precipitation data. There was a decrease in the area of water bodies (−9.9%), wetlands (−5.7%), and forest formation (−3.0%), accompanied by an increase in the area of pastureland (7.4%). The NDVI showed significant changes in vegetation cover (−069 to 0.81), while the MNDWI showed a decrease in water surface areas (−0.73 to 0.93) and the NDMI showed a continuous decrease in vegetation moisture (−0.53 to 1). Precipitation also decreased over the years, reaching a minimum of 595 mm. Vegetation indices and land use maps revealed significant changes in vegetation and loss of water bodies in the Pantanal, reinforcing the need for sustainable management, recovery of degraded areas, and promotion of ecotourism to balance environmental conservation and local development.

Water regime specifics in the upper Sviyaga River and its tributaries upon karst development

At present, the hydrological characteristics of small rivers are understudied in Russia. Taking into account the increasing deterioration of the ecological state of surface watercourses, which primarily affects the intra-annual distribution of water runoff on small and medium-sized rivers, in particular, the study of runoff formation, its variability and intra-annual changes become the most important task of hydrology. The paper considers changes in the indicators of intra-annual distribution of river flow in the upper reaches of the Sviyaga River in the almost complete absence of knowledge of changes in the flow of small and medium-sized rivers in the study area. It was necessary to identify what changes the water runoff from small and medium-sized rivers undergoes in the upper reaches of the Sviyaga River, which is complicated by the occurrence of karst. The paper presents an analysis of the intra-annual distribution of water runoff, and natural factors that have the maximum effect on the intra-annual distribution of water runoff for rivers in the study area, as well as its assessment against the background of climate change. The identified types of water regime are described. Based on the research results, a typification of rivers is proposed according to the annual water flow and zoning of cross-sections by river types. The intra-annual distribution of water levels and discharges are analyzed, the factors influencing them are assessed, and the most significant of them are identified.