Respiratory Pattern Research Articles

Biomass competition connects individual and community scaling patterns.

Both metabolism and growth scale sublinearly with body mass across species. Ecosystems show the same sublinear scaling between production and total biomass, but ecological theory cannot reconcile the existence of these nearly identical scalings at different levels of biological organization. We attempt to solve this paradox using marine phytoplankton, connecting individual and ecosystem scalings across three orders of magnitude in body size and biomass. We find that competitive interactions determined by biomass slow metabolism in a consistent fashion across species of different sizes. These effects dominate over species-specific peculiarities, explaining why community composition does not affect respiration and production patterns. The sublinear scaling of ecosystem production thus emerges from this metabolic density-dependence that operates across species, independently of the equilibrium state or resource regime. Our findings demonstrate the connection between individual and ecosystem scalings, unifying aspects of physiology and ecology to explain why growth patterns are so strikingly similar across scales.

Association between narrow palate and respiratory function in children: a literature review

Changes in the airways and dentoalveolar system are one of the most challenging aspects of modern practical and theoretical dentistry. Nasal breathing is essential for the normal development of the maxillofacial area. During a child’s growth, the respiratory tract and facial skull development are closely linked. The main stage of dentoalveolar system development occurs during preschool and elementary school years. Nasal breathing disorders are currently widespread in this age group. Dental professionals are frequently the first to detect these disorders. A dental professional can then inform parents on the potential causes and consequences of habitual mouth breathing, justify the need for treatment and prevention of this pathology, and refer a child to an ENT specialist. The review examines the association between narrow palate and respiratory function in children. Domestic and international studies addressing the association between dentoalveolar system pathologies and respiratory patterns and functional parameters were analyzed. The studies present a variety of opinions: some authors confirm the association between narrow palate and mouth breathing, while others refute it. Moreover, changes in respiratory function parameters following rapid palatal expansion have been analyzed, emphasizing the importance of timely orthodontic treatment to improve breathing.

Ultrasensitive, Fast-Response, and Stretchable Temperature Microsensor Based on a Stable Encapsulated Organohydrogel Film for Wearable Applications.

Ionic conductive hydrogel-based temperature sensors have emerged as promising candidates due to their good stretchability and biocompatibility. However, the unsatisfactory sensitivity, sluggish response/recovery speed, and poor environmental stability limit their applications for accurate long-term health monitoring and robot perception, especially in extreme environments. To address these concerns, here, the stretchable temperature sensors based on a double-side elastomer-encapsulated thin-film organohydrogel (DETO) architecture are proposed with impressive performance. It is found that the water-polyol binary solvent, organohydrogel film, and sandwiched device structure play important roles in the temperature sensing performance. By modifying the composition of binary solvent and thicknesses of organohydrogel and elastomer films, the DETO microsensors realize a thickness of only 380 μm, unprecedented temperature sensitivity (37.96%/°C), fast response time (6.01 s) and recovery time (10.53 s), wide detection range (25-95.7 °C), and good stretchability (40% strain), which are superior to those of conventional hydrogel-based sensors. Furthermore, the device displays good environmental stability with negligible dehydration and prolonged operation duration. With these attributes, the wearable sensor is exploited for the real-time monitoring of various physiological signals such as human skin temperature and respiration patterns as well as temperature perception for robots.

Respiratory tract bacteria distribution and transmission patterns among individuals in close contact.

Respiratory disease outbreaks frequently occur in settings where individuals are in close contact, for example, schools and factories. However, the transmission patterns of oropharyngeal microbiota among healthy individuals living in clusters are unclear. Therefore, we aimed to investigate the respiratory tract bacteria distribution and transmission patterns among individuals in close contact. A total of 36 freshmen from Peking University Medical School participated in the study. We collected pharyngeal swabs on the first day of enrollment, 15, 30, and 60 days after cohabitation. DNA was extracted from the swabs and subjected to high-throughput sequencing to profile the microbial composition. Statistical analyses were performed to assess diversity and significance. Neisseriaceae, Prevotellaceae, and Streptococcaceae were the most abundant bacterial families detected. Over time, changes were observed in the bacterial communities, with a tendency for increased similarity between dormitory room members. By day 60 of cohabitation, the bacterial communities appeared to be more similar compared to the baseline (prior to cohabitation). The transmission patterns included spreading with colonization, spreading without colonization, and non-spreading. Bacteria belonging to the core genera are most likely to spread and colonize easily. The risk of healthy cohabitants acquiring respiratory pathogens through close contact may be overestimated in epidemiological studies. Therefore, monitoring the spread of core genera that are easily transmitted and colonized is crucial for effective prevention of respiratory pathogen transmission.

Breathing modulates network activity in frontal brain regions during anxiety.

Anxiety elicits various physiological responses, including changes in respiratory rate and neuronal activity within specific brain regions such as the medial prefrontal cortex (mPFC). Previous research suggests that the olfactory bulb (OB) modulates the mPFC through respiration-coupled neuronal oscillations (RCOs), which have been linked to fear-related freezing behavior. Nevertheless, the impact of breathing on frontal brain networks during other negative emotional responses, such as anxiety-related states characterized by higher breathing rates, remains unclear. To address this, we subjected rats to the elevated plus maze (EPM) paradigm while simultaneously recording respiration and local field potentials in the OB and mPFC. Our findings demonstrate distinct respiratory patterns during EPM exploration: slower breathing frequencies prevailed in the closed arms, whereas faster frequencies were observed in the open arms, independent of locomotor activity, indicating that anxiety-like states are associated with increased respiratory rates. Additionally, we identified RCOs at different frequencies, mirroring the bimodal distribution of respiratory frequencies. RCOs exhibited higher power during open arm exploration, when they showed greater coherence with breathing at faster frequencies. Furthermore, we confirmed that nasal respiration drives RCOs in frontal brain regions, and found a stronger effect during faster breathing. Interestingly, we observed that the frequency of prefrontal gamma oscillations modulated by respiration increased with breathing frequency. Overall, our study provides evidence for a significant influence of breathing on prefrontal cortex networks during anxious states, shedding light on the complex interplay between respiratory physiology and emotional processing.Significance Statement Understanding how breathing influences brain activity during anxious states could pave the way for novel therapeutic interventions targeting respiratory control to alleviate anxiety symptoms. Our study uncovers a crucial link between respiratory patterns and anxiety-related neural activity in the brain. By investigating the interplay between breathing, neuronal oscillations, and emotional states, we reveal that anxiety induces distinct respiratory patterns, with higher breathing rates correlating with anxious behavior. Importantly, we demonstrate that respiration drives oscillatory activity in the prefrontal cortex, and this effect is potentiated during the fast breathing associated with anxiety. Furthermore, faster breathing modulates the emergence of faster prefrontal gamma oscillations. This discovery sheds new light on the intricate relationship between respiratory physiology and emotional processing.

A numerical evaluation of real-time workloads for ramp controller through optimization of multi-type feature combinations derived from eye tracker, respiratory, and fatigue patterns.

Ramp controllers are required to manage their workloads effectively while handling complex operational tasks, a crucial part of improving aviation safety. The ability to detect their instantaneous workload is vital for ensuring operational effectiveness and preventing hazardous incidents. This paper introduces a novel methodology aimed at enhancing the evaluation of the ramp controller's cumulative workload by incorporating and optimizing the feature combination from eye movement, respiratory, and fatigue characteristics. Specifically, a 90-minute simulated experiment related to ramp control tasks, using real data from Shanghai Hongqiao Airport, is conducted to collect multi-type data from 8 controllers. Following data construction and the extraction of multi-type, the workloads of all samples are categorized through unsupervised learning. Subsequently, supervised learning techniques are used to calculate feature weights and train classifiers after data alignment. The optimal feature combination is established by calculating feature weights, and the best classification accuracy is over 98%, achieved by the KNN classifier. Furthermore, numerical evaluation and threshold calculations for different workload levels are interpreted. It is promising to provide insights into future works towards human-centered data construction, processing, and interpretation to promote the progress of workload assessment within the aviation industry.

A longitudinal analysis of psychological, physiological, and rehabilitation outcomes in basketball players following acute sports injuries

This cross-sectional study examines psychological behavior, biological factors, and rehabilitation treatment concerning acute sports injuries involving basketball players. Psychological trauma is also prevalent whereby athletes develop anxiety, depression and or fear that slow down their healing process and inability. The present study is a naturalistic cohort design where 50 basketball players with an injury completing self-report measures such as DASS-21 (Depression, Anxiety and Stress Scale) and biological markers, cortisol level at monthly intervals for 12 months. Qualitative data in the form of interviews conducted after treatment, or quantitative data from neuropsychological examinations, are employed to determine therapeutic impacts of CBT and/or specified individual rehabilitation plans in changing psychological effects, regain biological functions, and the speed of physical rehabilitation. Current data analyzed evidence lower level of stress, cortisol, beneficial shifts in cardiovascular, respiratory patterns, and aspects of rehabilitation outcomes in the player receiving both psychological and physical-motor interventions in comparison to the group receiving only physical-motor treatment. Based on the developed arguments it can be seen that the mental health and the biological issues also matter thus boosting the believably of better rehabilitation for athletes.

Humans without a sense of smell breathe differently

Olfaction may play a restricted role in human behavior, yet paradoxically, its absence in anosmia is associated with diverse deleterious outcomes, culminating in reduced life expectancy. The mammalian nose serves two purposes: olfaction and breathing. Because respiratory patterns are impacted by odors, we hypothesized that nasal respiratory airflow may be altered in anosmia. We apply a wearable device that precisely logs nasal airflow for 24-hour-long sessions in participants with isolated congenital anosmia and controls. We observe significantly altered patterns of respiratory nasal airflow in anosmia in wake and in sleep. These differences allow classification of anosmia at 83% accuracy using the respiratory trace alone. Patterns of respiratory airflow have pronounced impact on health, emotion and cognition. We therefore suggest that a portion of the deleterious outcomes associated with anosmia may be attributed to altered patterns of respiratory nasal airflow rather than a direct result of lost odor perception per se.

Camera-Based Respiratory Imaging System for Monitoring Infant Thoracoabdominal Patterns of Respiration.

Existing respiratory monitoring techniques primarily focus on respiratory rate measurement, neglecting the potential of using thoracoabdominal patterns of respiration for infant lung health assessment. To bridge this gap, we exploit the unique advantage of spatial redundancy of a camera sensor to analyze the infant thoracoabdominal respiratory motion. Specifically, we propose a camera-based respiratory imaging (CRI) system that utilizes optical flow to construct a spatio-temporal respiratory imager for comparing the infant chest and abdominal respiratory motion, and employs deep learning algorithms to identify infant abdominal, thoracoabdominal synchronous, and thoracoabdominal asynchronous patterns of respiration. To alleviate the challenges posed by limited clinical training data and subject variability, we introduce a novel multiple-expert contrastive learning (MECL) strategy to CRI. It enriches training samples by reversing and pairing different-class data, and promotes the representation consistency of same-class data through multi-expert collaborative optimization. Clinical validation involving 44 infants shows that MECL achieves 70% in sensitivity and 80.21% in specificity, which validates the feasibility of CRI for respiratory pattern recognition. This work investigates a novel video-based approach for assessing the infant thoracoabdominal patterns of respiration, revealing a new value stream of video health monitoring in neonatal care.

Effects of Combined Respiratory Physiotherapy with High-Flow Nasal Cannula and Venturi Mask in Spinal Cord Injury: A Single-Subject Research Study and Literature Review.

The level of spinal cord injury affects the severity of respiratory impairment and the alteration of respiratory pattern and gas exchanges. Lesions at the C3-C5 level (phrenic nerve nucleus) cause disruption of descending input with paralysis of the main inspiratory muscle, often requiring tracheostomy and prolonged mechanical ventilation. Oxygen therapy is essential to switch from ventilatory support to removal of the endotracheal tube to correct residual difficulties in oxygenation management. A 58-year-old man had tracheostomy and tetraparesis as complication of tonsillectomy and adenoidectomy treatment for a history of obstructive sleep apnea. A respiratory rehabilitation program with protocol of oxygen therapy with high flow cannula alternated with a low-flow system by Venturi mask during daytime hours only was started. The patient was constantly monitored with capillary partial oxygen saturation to obtain adequate oxygenation (≥ 94%) and registered every 15 minutes in the clinical chart. There was gradual improvement of respiratory function. Oxygen by Venturi mask was gradually reduced due to improvement of partial pressure oxygen values. Over the course of days, the optimal results of respiratory parameters led to a gradual weaning from the Venturi mask until the complete discontinuation of the low-flow system during daytime and decreased of the high-flow fraction of inspired oxygen to the maximal tolerated level during nighttime. Implementing a combined protocol of nighttime oxygen with high flow cannula and daytime Venturi mask improves intensive motor training of patients by promoting the acquisition of ability to perform chair/bed transitions and to be able to achieve standing and begin gait training. More research is needed whether or noted to determine the role of this promising approach in patients with severe SCI and in other critically ill patients. This is a presentation of a new respiratory training protocol of combined oxygen therapy by high flow cannula and Venturi mask in a patient with cervical spinal cord injury and respiratory failure.Due to this new respiratory training, from the weaning of ventilation devices the patient had greater independence and improved quality of life, with more intensive motor training in the gym, improvement of the motor program and the patient tolerance to training.Oxygen therapy with high flow cannula and Venturi mask could be valid and reliable combined respiratory training to improve the respiratory pattern in severely hypoxemic and hypercapnic patients, without adverse events.

Respiratory-Swallow Coordination and Its Relationship With Pharyngeal Residue, Penetration, and Aspiration in People With Parkinson's Disease.

Respiratory-swallow coordination (RSC) frequently changes in people with Parkinson's disease (PwPD). Little is known about how these changes relate to impairments in swallowing safety (penetration and aspiration) and efficiency (pharyngeal residue). Therefore, the aims of this study were to assess the relationships between RSC, pharyngeal residue, penetration, and aspiration in PwPD. Twenty-four PwPD were recruited to undergo simultaneous assessment of RSC, swallowing safety, and swallowing efficiency. RSC was assessed using respiratory inductive plethysmography and nasal airflow and included measurements of respiratory pause duration, respiratory phase patterning, and lung volume during swallowing. Swallowing safety and efficiency were assessed using flexible endoscopic evaluation of swallowing, analyzed using the Visual Analysis of Swallowing Efficiency and Safety, and included measurements of pharyngeal residue, penetration, and aspiration. All data were blindly analyzed, with 20% of the data repeated for interrater reliability assessment. Multilevel statistical models were used to examine the relationships between RSC and swallowing. A total of 812 swallows were analyzed from 24 participants. Only 33.4% of swallows exhibited the typical exhale-swallow-exhale pattern. Additionally, 95% of participants exhibited abnormal swallow function. More severe hypopharyngeal residue ratings were associated with inhaling before the swallow compared to exhaling before the swallow. Additionally, more severe events of penetration and aspiration were associated with (a) inhaling before the swallow compared to exhaling before the swallow, (b) inhaling after the swallow compared to exhaling after the swallow, and (c) longer swallow-related respiratory pause durations. Inhaling after the swallow exhibited the strongest relationship with impairments in swallowing safety when compared to all other RSC variables. RSC exhibited significant relationships with pharyngeal residue, penetration, and aspiration in these PwPD. Clinicians should attend to RSC when assessing swallowing in PwPD. Future research is needed to examine if training an exhale-swallow-exhale pattern can be used to improve disordered swallowing in PwPD.

Respiratory phenotype and health care utilization patterns by adults with sickle cell disease

AbstractAdults with sickle cell disease (SCD) and asthma have increased mortality and health care utilization; however, there are individuals with respiratory symptoms (including cough and wheeze) without asthma. These individuals may have similar patterns of increased mortality and health care utilization. To characterize the association between respiratory phenotype and health care utilization by adults with SCD. Cross-sectional study of adults with SCD presenting for emergency and inpatient hospital care from 2012 to 2014 in Florida, Iowa, and New York using state-level health care utilization databases. Outcomes of interest include all-cause, SCD-related, painful episode, and acute chest syndrome–related care. Respiratory phenotype was defined as SCD + asthma, SCD + respiratory symptoms, and SCD + none. We built multivariable logistic regression and negative binomial regression models to evaluate the association adjusting for demographics, social determinant of health proxies, year of care, and state. Of 29 952 identified individuals, 3.4% had intermittent respiratory symptoms, and a larger proportion (15.6%) had asthma. There was a high rate of inpatient hospitalizations (43%) and ED visits (60%). Individuals with asthma had a higher annual risk of inpatient hospitalizations (48% vs 37%) but lower annual risk of an ED visit (62% vs 86%) than individuals with intermittent respiratory symptoms. The pattern of increased health care utilization among individuals with intermittent respiratory symptoms was consistent across each utilization type. In this large cohort of adults with SCD, we identified some with intermittent respiratory symptoms who had significantly increased health care utilization. This warrants further evaluation to understand potential etiologies and interventions.

Monitoring of Respiratory Disease Patterns in a Multimicrobially Infected Pig Population Using Artificial Intelligence and Aggregate Samples

A 24/7 AI sound-based coughing monitoring system was applied in combination with oral fluids (OFs) and bioaerosol (AS)-based screening for respiratory pathogens in a conventional pig nursery. The objective was to assess the additional value of the AI to identify disease patterns in association with molecular diagnostics to gain information on the etiology of respiratory distress in a multimicrobially infected pig population. Respiratory distress was measured 24/7 by the AI and compared to human observations. Screening for swine influenza A virus (swIAV), porcine reproductive and respiratory disease virus (PRRSV), Mycoplasma (M.) hyopneumoniae, Actinobacillus (A.) pleuropneumoniae, and porcine circovirus 2 (PCV2) was conducted using qPCR. Except for M. hyopneumoniae, all of the investigated pathogens were detected within the study period. High swIAV-RNA loads in OFs and AS were significantly associated with a decrease in respiratory health, expressed by a respiratory health score calculated by the AI The odds of detecting PRRSV or A. pleuropneumoniae were significantly higher for OFs compared to AS. qPCR examinations of OFs revealed significantly lower Ct-values for swIAV and A. pleuropneumoniae compared to AS. In addition to acting as an early warning system, AI gained respiratory health data combined with laboratory diagnostics, can indicate the etiology of respiratory distress.

Psychometric properties of the Turkish version of the developmental care scale for neonates with congenital heart disease.

Developmental care for newborns with congenital heart disease (CHD) improves cardiac and respiratory patterns. According to the American Heart Association, developmental care in newborns with CHD is important for improving neurodevelopmental outcomes. This study aimed to evaluate the validity and reliability of the Turkish version of the Developmental Care Scale for Neonates with Congenital Heart Disease. This was a methodological, descriptive study conducted with 169 nurses from a tertiary-level NICU. The Demographical Information Form and the Developmental Care Scale for Neonates with Congenital Heart Disease were used to collect the data. The scales' language and content validity, construct validity, and internal consistency were also assessed. The scale consists of 31 items and four subscales. Factor loadings ranged from 0.44 to 0.82 and explained 65% of the total variance. Fit indices indicate that the model is acceptable. Cronbach's α was 0.95 for the entire instrument, 0.91 for developing the external environment subscale, 0.94 for assessing family well-being, 0.86 for the caregiver activities toward the neonate, and 0.82 for the basic need subscale. Item-total correlations ranged between 0.34 and 0.75, according to the item analysis results. The Turkish version of the Developmental Care Scale for Neonates with Congenital Heart Disease is valid and reliable. The use of this scale could improve the performance of neonatal intensive care nurses in providing developmental care to newborns with CHD as well as the quality of care.

Role of the Kölliker-Fuse/parabrachial complex in the generation of postinspiratory vagal and sympathetic nerve activities and their recruitment by hypoxemic stimuli in the rat.

In the rat, the activity of laryngeal adductor muscles, the crural diaphragm, and sympathetic vasomotor neurons is entrained to the postinspiratory (post-I) phase of the respiratory cycle, a mechanism thought to enhance cardiorespiratory efficiency. The identity of the central neurons responsible for transmitting respiratory activity to these outputs remains unresolved. Here we explore the contribution of the Kölliker-Fuse/parabrachial nuclei (KF-PBN) in the generation of post-I activity in vagal and sympathetic outputs under steady-state conditions and during acute hypoxemia, a condition that potently recruits post-I activity. In artificially ventilated, vagotomized, and urethane-anesthetized rats, bilateral KF-PBN inhibition by microinjection of the GABAA receptor agonist isoguvacine evoked stereotypical responses on respiratory pattern, characterized by a reduction in phrenic nerve burst amplitude, a modest lengthening of inspiratory time, and an increase in breath-to-breath variability, while post-I vagal nerve activity was abolished and post-I sympathetic nerve activity diminished. During acute hypoxemia, KF-PBN inhibition attenuated tachypneic responses and completely abolished post-I vagal activity while preserving respiratory-sympathetic coupling. Furthermore, KF-PBN inhibition disrupted the decline in respiratory frequency that normally follows resumption of oxygenation. These findings suggest that the KF-PBN is a critical hub for the distribution of post-I activities to vagal and sympathetic outputs and is an important contributor to the dynamic adjustments to respiratory patterns that occur in response to acute hypoxia. Although KF-PBN appears essential for post-I vagal activity, it only partially contributes to post-I sympathetic nerve activity, suggesting the contribution of multiple neural pathways to respiratory-sympathetic coupling.NEW & NOTEWORTHY Inhibition of neurons in the pontine Kölliker-Fuse/parabrachial complex (KF-PBN) differentially inhibited postinspiratory (post-I) activity in vagal and sympathetic outputs. The strong recruitment of post-I vagal activity that occurs in response to hypoxemia is selectively abolished by KF-PBN inhibition. This suggests that 1) post-I activity in vagal and sympathetic outputs may be generated by partially independent mechanisms and 2) neurons in the KF-PBN are a preeminent source of drive for the generation of eupneic post-I activity.

Impact of SARS-CoV-2 viral load on restrictive spirometry patterns in mild COVID-19 recovered middle-aged individuals: a six-month prospective study

BackgroundLong term respiratory complications of Corona Virus Disease-2019 (COVID-19) are of great concern. Many studies have reported altered respiratory patterns in COVID-19 recovered individuals and most of them were from severe to critically ill patients. The association of viral load at the time of infection with symptoms of long COVID-19 specifically on pulmonary functions after months of recovery is still not known. This study was aimed to assess the impact of SARS-CoV-2 viral load during mild-moderate COVID-19 disease on pulmonary functions in middle-aged population after 6–8 months of acute infection.MethodsThis study included 300 (102 healthy controls and 198 COVID-19 recovered) individuals between age 30–60 of either gender. Mild-moderate COVID-19 recovered individuals were recruited between a period of 6–8 months post-acute infection. Spirometry was performed with MIR-Spirolab-III. The association of spirometry pattern was compared with SARS-CoV-2 viral loads during acute infection.ResultsWe observed up to 70% of the participants presented with either shortness of breath (11.5%), body aches (23.5%), recurrent cough (4.4%), recurrent respiratory infections (9.5%) and/or fatigue (33.3%) at follow up. In our study, 35.5% of COVID-19 recovered individuals had abnormal respiratory patterns (33.5% had restrictive and 2% had obstructive patterns). Viral load ≤ 20 CT value was associated with restrictive respiratory patterns (p = 0.004). No association was found between viral load and disease severity (p = 0.23).ConclusionIn this study, we found one third of mild-moderate COVID-19 recovered individuals have restrictive respiratory patterns after 6–8 months of recovery. These findings had a strong association with SARS-CoV-2 viral loads during acute infection which has been reported for the first time in our study. Studying the relationship between viral load and pulmonary functions can contribute to identifying potential risk factors for long COVID and developing preventive measures to mitigate the long-term impact on lung health.Clinical trial numberNot applicable.

A dual wave structure triboelectric sensor for heart rate and exercise monitoring

Recently, research on wearable devices for physiological exercise monitoring has garnered significant attention. Here, we propose a dual wave-structured triboelectric nanogenerator (DW-TENG) integrated with a cotton cloth, developed for smart running applications. The DW-TENG sensor leverages a flexible wave triboelectric layer composed of polydimethylsiloxane and silicone, with a copper electrode layer between them for sensing. This structure allows for customizable pressure sensitivity by adjusting the silicone hardness. Experimental results show that the DW-TENG achieves a sensitivity of 0.4 V kPa−1, with response and recovery times of 75 and 90 ms, respectively. The sensor effectively measures heart rate changes during various physical activities, including walking, running, and jumping. Electrical performance tests reveal that the DW-TENG’s output is significantly influenced by the silicone hardness, operational frequency, and microstructure height. The DW-TENG sensor demonstrates high durability and stability, maintaining consistent voltage output over 40 000 cycles. This research highlights the potential of the DW-TENG in multifunctional physiological and physical activity monitoring, providing real-time data on respiratory patterns, heart rate, and movement dynamics, thus enhancing athletic training, performance assessment, and health monitoring.

Changes in respiratory patterns, aerobic capacity, and 40-km time trial performance after 10-week endurance training with voluntarily slowed respiratory rate for cyclists and triathletes

Changes in respiratory patterns, aerobic capacity, and 40-km time trial performance after 10-week endurance training with voluntarily slowed respiratory rate for cyclists and triathletes

Breathing pattern alteration from weanling to old age in male Sprague-Dawley rats

Respiratory patterns were investigated in male Sprague-Dawley rats throughout their lifespan, from weanling (1 month) to old age (24 months), under natural conditions. Both inter-breath interval (IBI) and respiratory volume (RV) were examined. Sample entropy suggested increasing irregularity in IBI but decreasing irregularity in RV until 12 months. According to detrended fluctuation analysis, alpha exponent of the IBI showed a bimodal pattern around the value 0.7. From 1–15 months, the alpha exponent for RV generally decreased to the value 0.5, but it increased again as the animals neared the end of their lifespan. Cross-sample entropy revealed increasing synchronization between IBI and RV until 12 months, then plateauing. Many measures demonstrated a transition around 12 months, potentially reflecting maturation of respiratory control mechanisms. The findings characterize complex dynamics of respiratory patterns across the rat lifespan, providing a normative foundation to identify deviations indicative of dysfunction or disease.

Ultrasensitive and durable borophene-based humidity sensors for advanced human-centric applications

Borophene, a novel two-dimensional (2D) nanomaterials with high surface-to-volume ratio and abundant active sites, show great promise for humidity sensing applications, which are crucial for improving human comfort, public health, and device safety. However, traditional fabrication methods, such as drop-coating, face limitations including uncontrollable sensing layer thickness, poor water-damage resistance, and inherent variability between devices. In this work, we present a high-performance humidity sensor fabricated using borophene glass. The sensor demonstrates an impressive detection range (11–97 % RH), exceptional sensitivity (up to 1.83×105% at 97 % RH), low hysteresis (1.245 %), excellent repeatability, and relatively fast response (28.8 s)/recovery (2.6 s) times. Notably, the sensor exhibits thickness-dependent sensing performance, long-term stability, high selectivity, and water-damage resistance. First-principles calculations show that borophene exhibits an adsorption energy of 0.208 eV for H2O molecules, with the hole doping effect following adsorption driving the sensor’s response to varying relative humidity levels. The sensor’s sustained heightened sensitivity under high humidity conditions is attributed to the Grotthuss mechanism. Additionally, the sensor has been successfully integrated into various human-centric applications, including speech recognition, wireless monitoring of respiratory patterns, and non-contact switches. These advancements pave the way for the integration of borophene humidity sensors into smart devices and non-contact control systems, driving innovation in human–computer interaction and healthcare technologies.