Search Results (1,247)

Providing a healthy environment in schools, particularly during a global pandemic, is crucial to saving occupants’ lives and reducing infection rates. This paper proposes a novel desk local exhaust ventilation (DLEV) system that uses a local exhaust diffuser integrated into a classroom desk. The performance of the system in providing a healthy and comfortable indoor thermal environment and reducing the risk of COVID-19 infection was assessed numerically. The assessment combined indoor thermal comfort indices and the bioaerosol dispersion behavior of airborne particles. The study was completed in a typical classroom layout, in which the results show that the DLEV system meets thermal comfort requirements by maintaining the gradients of vertical temperature within an acceptable range. The DLEV system increases the air motion in the breathing zone while keeping it within the recommended range of <0.25 m/s. The PMV and PPD indices are within recommended comfort levels for all but three occupants. Most notably, the DLEV system substantially reduces the concentration of bioaerosols, especially around the occupants’ head. This system works by capturing and removing the virus-rich aerosols exhaled by infected subjects before they disperse in the classroom. This lowers the risk of infection among healthy subjects. These findings confirm the effectiveness of the DLEV system in enhancing both thermal comfort and indoor air quality, making it suitable for environments where specific goals regarding occupants’ health and thermal management are required, such as in a classroom of healthy and infected subjects. Full article

Background: Individuals with spinal cord injury (SCI) frequently experience chronic pain, trunk instability, and respiratory dysfunction. This pilot trial investigated the synergistic effects of a combined neuro-orthotic approach (thoracolumbosacral orthosis (TLSO) plus transcutaneous electrical nerve stimulation (TENS)) versus TLSO alone on pain, trunk control, and respiratory function in chronic incomplete SCI. Methods: Twelve adults with chronic incomplete SCI (T6–T12) were randomized to a combined group (TLSO + TENS) or a control group (TLSO alone) for a four-week intervention. Outcomes included pain (Visual Analogue Scale), trunk control (Trunk Assessment Scale), and respiratory function (tidal volume [VT], respiratory rate [RR], oxygen uptake [VO₂], ventilatory equivalent for oxygen [VE/VO₂], and inspiratory duty cycle [Ti/Ttot]) assessed at three time points (before intervention, immediately after intervention, and after one month). Results: The combined group demonstrated a significant reduction in pain (47.8% vs. 10.4%, p = 0.01) and an improvement in Ti/Ttot (33.3% vs. 4.9%, p = 0.008) compared to the control group. Both groups showed significant improvements in VT and RR over time (p < 0.05), reflecting the biomechanical benefits of TLSO. Conclusions: Integrating TENS with TLSO offers a non-invasive strategy for managing chronic pain and improving respiratory pattern coordination in incomplete SCI. While TLSO optimizes basic ventilatory mechanics, adding TENS significantly enhances neural drive for efficient breathing and pain gating. Future large-scale trials incorporating active task-specific training are needed to restore functional trunk control. Full article

Background: Device-independent, lifestyle-integrated active pursed-lip diaphragmatic breathing (PLDB) may overcome respiratory rehabilitation barriers in chronic heart failure (CHF). This retrospective real-world study evaluated its prognostic association with functional capacity, quality of life (QoL), and major adverse cardiovascular events (MACE). Methods: A total of 58 CHF patients (NYHA II–IV) were categorized by 6-month post-discharge PLDB adherence into a Respiratory Training Group (RTG; n = 20) and Control Group (n = 38). Functional, structural, QoL metrics, and MACE outcomes were analyzed. Results: After 6 months, the RTG demonstrated significant intra-group improvements in 6 min walk test (6MWT) distance (302.00 [243.60, 408.15] m to 386.00 [339.50, 439.00] m, p = 0.006; baseline-adjusted between-group gain: +76.16 m), handgrip strength (p = 0.046), LVEF (p = 0.003), and scores on the Minnesota Living with Heart Failure Questionnaire (MLHFQ) (p < 0.001), Generalized Anxiety Disorder-7 (GAD-7) (p = 0.010), and Self-rating Somatic Symptom Scale-China (SSS-CN) (p = 0.004). Post-intervention, the RTG outperformed controls in handgrip strength (p = 0.012), MLHFQ (p = 0.001) and SSS-CN (p = 0.020). The RTG exhibited a significantly lower MACE incidence (5.0% vs. 42.1%, p = 0.003) and superior MACE-free survival (log-rank p = 0.005). Multivariable Cox regression confirmed high PLDB adherence was independently associated with a lower MACE risk (adjusted HR = 0.103, 95% CI: 0.014–0.779, p = 0.028). Conclusions: High adherence to a 6-month lifestyle-integrated PLDB program correlates with clinically meaningful improvements in exercise capacity, cardiac function, and QoL, and is independently associated with a lower risk of short-term MACE in CHF patients. Full article

Background: Prostaglandin E₂ (PGE₂) suppresses perinatal breathing. Reducing antenatal PGE₂ concentrations with paracetamol could stimulate spontaneous breathing in premature infants at birth. We aimed to assess feasibility and potential effects of antenatal paracetamol. Methods: In this randomised, placebo-controlled, triple-blind feasibility trial, pregnant women <31 weeks’ gestation were randomised to receive either intravenous paracetamol (intervention) or placebo (control). Multiple pregnancies were also eligible, and the number of infants could exceed the number of enrolled women. The primary outcome was feasibility of administering study medication within 30–120 min prior to birth. Secondary exploratory outcomes included measures of breathing and other physiological parameters of infants during the first 1–10 min after birth and were compared between infants from mothers who received paracetamol and infants from mothers who received a placebo irrespective of timing of administration. Planned enrolment was 40 women. Results: The trial enrolled 23 women before termination due to low recruitment. Five women did not receive study medication, while 18 did (9 per group). Overall, 11 of the 23 enrolled women (48%) received study medication within the specified timeframe. The nine women in the intervention group gave birth to 13 infants, while the nine women in the control group gave birth to 12 infants. Among infants, average minute volume did not differ significantly between groups (intervention (n = 13) vs. control (n = 12); mean ± SEM; 147 ± 12 vs. 114 ± 14 mL/kg/min, p = 0.093). However, the intervention group had a significantly higher area under the curve for minute volume, greater inspiratory drive, and a higher heart rate (1120 ± 410 vs. 707 ± 346 mL/kg, p = 0.020; 11.8 ± 1.0 vs. 8.4 ± 1.3 mL/kg/breath/s, p = 0.046; 137 ± 5 vs. 121 ± 5 beats/min, p = 0.037). Conclusions: Antenatal paracetamol administration 30–120 min prior to birth was feasible in only half of the women, below the pre-specified threshold of 80%, but the exploratory findings suggest that it may improve the breathing effort of premature infants. Full article

The maximum carboxylation rate (V_cmax) is a key parameter determining photosynthetic capacity in terrestrial biosphere models, yet its variability is often oversimplified as a plant functional type-dependent constant, increasing uncertainties in gross primary productivity (GPP) simulations. In this study, we inverted the daily V_cmax normalized to 25 °C (V_m25) by coupling the Breathing Earth System Simulator (BESS) model with the light response curves (LRC) method using eddy covariance observations at five maize sites in the United States and China. Then, four machine learning (ML) models—KNN, SVM, Random Forest (RF) and XGBoost—were employed to simulate V_m25, with RF showing the best performance (R² = 0.83, RMSE = 7.57 μmol m⁻²s⁻¹ for testing). Cross-validation further demonstrated the RF model’s ability to capture seasonal trends across sites. Incorporating the RF-simulated V_m25 into the BESS model significantly improved GPP estimates compared to the original BESS, with R² increasing from 0.53–0.81 to 0.77–0.84. Through the SHAP method and ablation experiments, leaf age was identified as the most influential factor, with the largest SHAP value of 8.37 μmol m⁻²s⁻¹, higher than that for temperature (4.47 μmol m⁻²s⁻¹), solar radiation (4.21 μmol m⁻²s⁻¹) and leaf area index (2.32 μmol m⁻²s⁻¹). And vapor pressure deficit had the minimal SHAP value of 0.87 μmol m⁻²s⁻¹. Notably, the effect of leaf age on V_m25 exhibited a unimodal pattern, with a strong coupling effect with leaf area index. This study demonstrates that interpretable machine learning not only provides a robust approach for simulating seasonally dynamic V_cmax, but also enhances our understanding of its driving biological and environmental factors, offering a valuable pathway for improving carbon cycle modeling in agroecosystems. Full article

Background/Objectives: Propofol is effective for pediatric endoscopy but can depress ventilation. We compared three induction regimens in school-aged children undergoing bidirectional gastrointestinal endoscopy. Methods: This single-center, assessor-blinded randomized trial allocated children aged 6–12 years (1:1:1) to propofol 3 mg/kg (P), remimazolam 0.2 mg/kg plus propofol 1 mg/kg (R1), or remimazolam 0.4 mg/kg plus propofol 1 mg/kg (R2). All groups received sufentanil and standardized propofol maintenance. Respiratory depression was a respiratory rate < 10 breaths/min or peripheral oxygen saturation < 90% for >1 min. The trial was prospectively registered (ChiCTR2500096218), and analysis followed assigned groups. Results: The analysis included 120 children (40 per group). Respiratory depression occurred in 32/40 (80.0%) in P, 6/40 (15.0%) in R1, and 14/40 (35.0%) in R2 (overall p < 0.001). Compared with P, the risk difference was −65.0 percentage points for R1 (95% confidence interval [CI], −77.4 to −44.6; risk ratio, 0.19; 95% CI, 0.09–0.37) and −45.0 percentage points for R2 (95% CI, −61.0 to −23.6; risk ratio, 0.44; 95% CI, 0.27–0.66); both Holm-adjusted p values were <0.001. Mean time to eye opening was 12.7, 11.2, and 16.9 min, respectively. In the exploratory R1-versus-R2 comparison, time to eye opening was 5.75 min shorter with R1 (95% CI, 4.28–7.20). Conclusions: Both remimazolam–propofol regimens reduced monitor-defined respiratory depression compared with propofol 3 mg/kg. The 0.2 mg/kg remimazolam–propofol regimen combined this respiratory benefit with faster recovery than the 0.4 mg/kg regimen in exploratory analysis, supporting its further evaluation as an induction strategy for pediatric bidirectional endoscopy. Full article

Smart textiles offer promising opportunities to address multiple aspects of relaxation-focused mental health interventions, which include monitoring and therapy. This paper presents a usability evaluation of a cushion-based smart textile system called Amiga, designed to guide users through breathing exercises that could be used in the future to support relaxation-focused interventions intended for independent use. A experimental user study with 20 participants was conducted to assess the system’s effectiveness, user performance, user experience, and overall satisfaction using structured interviews and validated usability questionnaires. The system achieved a mean System Usability Scale (SUS) score of 81.875 with standard deviation ($\sigma$ = 11.8), exceeding the established SUS benchmark of 68 and corresponding to the ‘Excellent’ category rating, under a predefined assistance-free criterion. The system was designed for respiratory phases (Ph) and respiration rate (RR) monitoring through a guided-breathing exercise where 90% completed with only 40% passing the quality criteria, achieving an average pace synchronization accuracy (PSA) of 61.2 % and phase duration accuracy (PDA) of 30% with a tolerance of ±1 s, thus providing a initial baseline for autonomous use and highlighting opportunities to improve on-boarding and in-application guidance. Most participants reported positive feedback regarding their confidence and overall satisfaction. Usability challenges were identified related to physical interaction with the cushion and clarity of on-screen instructions, providing clear directions for future design refinement. These findings demonstrate the feasibility of smart textile-based devices for home-based breathing exercises. Full article

The growing demand for wearable and Internet of Medical Things (IoMT) devices is driving the development of compact, low-power platforms for continuous physiological monitoring. Bioimpedance analysis represents a versatile non-invasive technique for the assessment of tissue properties, body composition, and respiratory dynamics. This work presents a comprehensive experimental validation of a compact bioimpedance measurement platform based on the SENSIPLUS chip, a CMOS sensor interface integrating a frequency-programmable lock-in amplifier for Electrochemical Impedance Spectroscopy in the 10 kHz–1 MHz range. The platform was validated at three complementary levels: (i) electrical characterization on Debye tissue-equivalent circuits using a three-point bilinear calibration, with analysis of the electrode–skin contribution and repeatability assessment; (ii) in vivo multi-frequency bioimpedance spectroscopy (BIS) with Cole–Cole model fitting and hook-effect correction; and (iii) single-frequency thoracic impedance plethysmography for respiratory monitoring. Results were compared against an Agilent E4980A precision Inductance (L), Capacitance (C), and Resistance (R) meter and a calibrated spirometer. The presented device achieved a maximum resistance error below 5.7% and reactance deviation under 6 $\mathsf{\Omega }$ across the investigated frequency range, Cole–Cole parameters consistent with reference values, and strong linear correlation ($R^2=0.97$) between thoracic impedance variations and tidal volume, with respiratory rate estimation errors below 2% across the ten sessions, specifically 1.43% during normal breathing and 1.96% during deep breathing. These results demonstrate that the SENSIPLUS-based platform achieves metrological performance compatible with the requirements of wearable IoMT applications, here demonstrated in a single-subject proof-of-concept study, while relying for all critical analog functions on a compact ($1.5\times 1.5$) mm² system-on-chip with low power consumption (1.5 mW). Full article

Respiratory infectious diseases pose substantial transmission risks in enclosed public-transport environments. Under a defined fully seated reference scenario, this study examines whether the same HVAC supply parameter governs two respiratory-particle control objectives in a subway carriage: whole-carriage particle removal and local seated breathing-zone exposure. Computational fluid dynamics (CFD) simulations, single-factor analyses, an L16 orthogonal design, analysis of variance (ANOVA), and grey relational analysis (GRA) were used to evaluate supply velocity, temperature, and angle. The results reveal an objective-dependent control hierarchy. Supply velocity is the leading factor for whole-carriage removal (contribution rate, 40.14%; p = 0.047), whereas supply angle contributes most to the seated breathing-zone particle proportion (59.30%), although the corresponding ANOVA result does not reach statistical significance at the 0.05 level (p = 0.056). The two single-objective optima share the same velocity and angle but differ in temperature, indicating a partial rather than complete mismatch. GRA identifies 2.0 m/s, 24 °C, and 0° as the best compromise among the investigated cases. This combination is specific to the modeled carriage, passenger arrangement, source location, and operating conditions. The more generalizable finding is that global clearance and local breathing-zone exposure are governed by different control variables. Full article

Heart rate variability (HRV) monitoring is commonly used in sport and exercise science to assess recovery, training adaptation, and performance readiness. However, the routine reporting of numerous HRV metrics with substantial conceptual and physiological overlap has created inconsistency regarding which indices should be prioritized for applied monitoring. This narrative review synthesizes the contemporary literature to provide practical recommendations regarding HRV metric selection in applied monitoring, with particular emphasis on whether the root mean square of successive differences between adjacent normal-to-normal intervals (RMSSD) may serve as the primary metric for routine HRV monitoring in many healthy sport and exercise populations. RMSSD demonstrates several characteristics favorable for applied monitoring, including strong physiological relevance, favorable reliability, compatibility with ultra-short recording durations, relative robustness during spontaneous breathing, computational simplicity, and suitability for longitudinal monitoring frameworks. Although additional HRV metrics remain valuable for addressing specific physiological, mechanistic, or research questions, the current evidence supports RMSSD as the primary metric for routine HRV monitoring in many sport and exercise settings. Full article

Background/Objectives: Guillain–Barré syndrome (GBS) is an acute immune-mediated disorder of the peripheral nervous system. Autonomic involvement in GBS occurs during the acute phase and may persist into the recovery phase. This study aimed to investigate the autonomic nervous system’s function in GBS sufferers. Methods: A cross-sectional exploratory study was conducted at the Clinical Neurophysiology Laboratory, Medical School, University of Cyprus. Eligible patients were previously hospitalized with GBS. Autonomic nervous system assessment included the Ewing battery using the Finapres Nova system as well as sudomotor assessment. Results: Seventeen patients were recruited (53% female; mean age 58.7 ± 14.1 years). The mean follow-up time since diagnosis was 15.5 ± 13.2 months (range 1–45 months). At follow-up, 4/17 patients (24%) demonstrated an abnormal heart rate (HR) response to standing, 3/17 patients (18%) exhibited an abnormal systolic blood pressure (BP) response to standing, and 4/17 patients (24%) exhibited an abnormal diastolic BP response to standing. One patient (6%) demonstrated an abnormal HR response during deep breathing, while another showed an abnormal diastolic BP response during the handgrip test. Overall, 6/17 patients (35%) showed abnormal findings in at least one component of the Ewing battery, and 3/17 (18%) fulfilled the criteria for definite generalised dysautonomia. Two patients (12%) demonstrated abnormal sympathetic skin response (SSR) results; both fulfilling the criteria for dysautonomia based on the Ewing battery. Conclusions: Autonomic dysfunction may be present in GBS patients beyond the acute phase, even in the absence of overt autonomic symptoms. Larger prospective studies with serial autonomic assessments are required to better characterise the long-term course and clinical significance of dysautonomia in GBS. Full article

The demand for a versatile and portable point-of-use (POU) sensor platform has surged due to the pandemic, especially in countries with limited medical laboratory facilities. We recently unveiled a portable, non-planar, interdigitated, flow-through, porous electrode platform that automatically measures electrochemical impedance spectroscopy (EIS) signals from various biomarkers. However, the packed powder exhibited a loss of performance over time due to displacement, leaching, and poor stability. Herein, we modified the packing strategy by synthesizing the sensing material within the channel, thereby improving adhesion, structural integrity, and stability. Leveraging the exceptional thermal stability, mechanical strength, and chemical resistance of polyimide (PI), we developed a novel fabrication approach that combines liquid-phase inversion and breath-figure techniques to create a porous PI manifold with single-walled carbon nanotubes (SWCNTs) under varying humidity conditions. Scanning electron microscope (SEM) analysis revealed that lower relative humidity (RH) conditions yield larger but less uniformly distributed pores, leading to increased channel pressure. The manifold demonstrated exceptional stability under rigorous flow conditions, withstanding a high flow rate of 30 µL/min while maintaining consistent pressure-EIS responses. The device produced a measurable proof-of-concept impedance response following exposure to a femtomolar concentration of complementary target ssDNA in 1× PBS within 15 min. A formal limit of detection was not determined in the present study. We developed a mechanically stable sensor design with improved durability under repeated flow conditions by systematically optimizing synthesis conditions and manifold configuration. This innovative fabrication strategy demonstrates the importance of packing methodology in sensor design and paves the way for robust, scalable, and efficient diagnostic solutions in resource-limited settings. Full article

Background/Objectives: Children with cancer admitted to the pediatric intensive care unit (PICU) are at increased risk for post-intensive care syndrome (PICS-p) due to prolonged immobility, deep sedation, and severe illness. The ABCDEF bundle offers a framework for enhancing ICU care and patient recovery, but implementing all components in pediatric oncology patients is challenging. This study assesses the development and implementation of the BRAVE (Beginning Restorative Activities Very Early) initiative, specifically BRAVE2, to integrate the comprehensive ABCDEF bundle and a nurse-led mobility program, in collaboration with rehabilitation specialists, within a pediatric oncology intensive care unit. Methods: BRAVE2 was a quality improvement project conducted in a single pediatric ICU from 2022 to 2023. We analyzed ICU data to assess patient demographics, frequency of physical and occupational therapy (PT/OT) consultations, time to initial mobilization, and delirium screening rates (CAPD score of 9 or higher) for patients with ICU stays over 48 h. BRAVE2 addressed all elements of the ABCDEF bundle, including regular pain assessments, evaluation of spontaneous breathing readiness, sedation adjustments, delirium screening, early mobilization, and family engagement. Outcomes were monitored using statistical process control methods. Results: Of 140 patients, 117 (84%) remained in the ICU for more than 48 h. The delirium screening rate was 15.5%, consistently below the target of 30%. PT/OT consultations within 72 h occurred in 80.7% of patients, and early mobilization in 49.7% of patients, both below the 80% goal. However, 90.4% of patients with tracked mobility were able to ambulate during their ICU stay. No mobility-related safety incidents were reported. Conclusions: Rolling out a full ICU liberation plan in a pediatric oncology ICU is possible, and implementing a comprehensive one is feasible and sustainable despite challenges. Although therapist-led early mobilization did not meet targets, incorporating nurse-led mobility strategies and routine delirium screening has established a scalable model to enhance ICU care and support long-term recovery for these patients. Full article

Background/Objectives: Opioids inhibit breathing that can lead to fatal overdose, highlighting the need for testing effective countermeasure agents and potential mechanisms of action. Here we examined the role muscarinic cholinergic receptors play in the ability of L-cysteine ethyl ester (L-CYSee) to overcome the deleterious effects of morphine on ventilatory parameters in male Sprague Dawley rats and the ventilatory responses during a subsequent hypoxic-hypercapnic (HH) challenge. Methods: Ventilatory parameters were measured by whole body plethysmography. Results: The injection of the muscarinic receptor antagonist, atropine (1.0 mg/kg, IV), elicited an array of ventilatory responses (e.g., an increase in frequency of breathing coupled with a fall in tidal volume). Injection of morphine (10 mg/kg, IV) to vehicle-treated rats elicited a depression of breathing, including sustained decreases in tidal volume, minute ventilation, peak inspiratory flow, and peak inspiratory and expiratory drives, which were associated with marked increases in end inspiratory pause (EIP) and end expiratory pause (EEP), expiratory flow at 50% expired tidal volume (EF₅₀), and rate of achieving peak expiratory flow (Rpef). Most effects of morphine (10 mg/kg, IV) were not altered in atropine-treated rats, except that increases in EIP, EEP and Rpef were reduced. Subsequent injections of L-CYSee (2 × 500 μmol/kg, IV given 15 min apart) overcame the adverse actions of morphine on ventilatory parameters in vehicle-treated rats. The effects of L-CYSee, such as reversal of the effects of morphine on frequency of breathing, tidal volume and minute ventilation, were markedly reduced in atropine-treated rats. The ability of L-CYSee to reverse the adverse effects of morphine to a HH gas challenge was markedly diminished in atropine-treated rats. Conclusions: These findings demonstrate that muscarinic receptors play a vital role in the ability of L-CYSee to overcome the deleterious effects of morphine. Full article

Construction dust is a major contributor to urban inhalable particulate matter (PM₁₀) pollution, posing severe respiratory and cardiovascular health risks to construction workers and nearby residents, severely undermining urban environmental sustainability. Construction fences are widely adopted as a primary dust mitigation measure, yet their underlying dispersion mechanisms and comprehensive impacts on vertical air quality remain poorly understood due to the limitations of traditional field monitoring and empirical models, creating critical barriers to site-level pollution control and long-term urban sustainability. In this study, a reliable computational fluid dynamics (CFD) method was developed to investigate the spatial distribution of construction dust and quantify the dust suppression performance of fences with heights ranging from 0 to 3 m. Three mainstream k-ε turbulence models (Standard, RNG, and Realizable) were evaluated using on-site measurement data, and the RNG k-ε model was found to provide the best agreement with field observations, with statistical metrics of q = 1, FB = 0.052, and NMSE = 0.028. The results show that construction fences effectively reduce dust dispersion into the surrounding environment, particularly in the pedestrian breathing zone (z < 1.5 m). Increasing the fence height from 1.5 m to 3 m improves the breathing-zone dust reduction rate from 39% to 55%, with the most significant mitigation effect observed within 50 m downwind of the fence. However, a critical dual effect was identified: while fences suppress near-ground pollution, they induce strong upward airflow and turbulence, leading to elevated dust concentrations in the upper part of the near-ground region (z = 1.5–9 m), a phenomenon absent in the no-fence scenario. These findings provide practical implications for urban construction site management, suggesting that fence height and configuration should be carefully designed not only to reduce pedestrian-level exposure but also to avoid unintended pollutant accumulation aloft, thereby improving overall air quality control strategies and delivering balanced, long-term environmental sustainability at construction sites. Full article