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Search Results (180)

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Keywords = exhalation rate

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16 pages, 1677 KiB  
Article
222Rn Exhalation Rate of Building Materials: Comparison of Standard Experimental Protocols and Radiological Health Hazard Assessment
by Francesco Caridi, Lorenzo Pistorino, Federica Minissale, Giuseppe Paladini, Michele Guida, Simona Mancini, Domenico Majolino and Valentina Venuti
Appl. Sci. 2025, 15(14), 8015; https://doi.org/10.3390/app15148015 - 18 Jul 2025
Viewed by 228
Abstract
This study evaluates the accuracy of 222Rn exhalation rates from building materials using two standard experimental protocols, thus addressing the increasing importance of rapid radon assessment due to health concerns and regulatory limits. In detail, six types of natural stones frequently employed [...] Read more.
This study evaluates the accuracy of 222Rn exhalation rates from building materials using two standard experimental protocols, thus addressing the increasing importance of rapid radon assessment due to health concerns and regulatory limits. In detail, six types of natural stones frequently employed for the construction of buildings of historical-artistic relevance were analyzed using the closed chamber method (CCM) combined with the Durridge Rad7 system, by using two experimental protocols that differed in the measurement duration: 10 days (Method 1) versus 24 h (Method 2). Obtained results revealed that the radon exhalation rates ranged from 0.004 to 0.072 Bq h−1, which are moderate to low if compared to studies in other regions. Statistical comparison using the u-test confirmed equivalence between protocols (u-test ≤ 2), thus supporting the validity of the faster Method 2 for practical applications. Furthermore, to estimate the potential indoor radon levels and determine the associated radiological risks to human health, for the investigated natural stones, the Markkanen room model was employed. As a result, simulated indoor radon concentrations remained well below regulatory thresholds (maximum value: 37.3 Bq m−3), thus excluding any significant health concerns under typical indoor conditions. Full article
(This article belongs to the Section Environmental Sciences)
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14 pages, 1884 KiB  
Article
Study of Radon Radiation in the Area of the Akchatau Polymetallic Mine, Republic of Kazakhstan
by Yuriy Pak, Dmitriy Pak, Vladimir Matonin, Diana Ibragimova, Pavel Timoshenko, Yuriy Barkov, Anar Tebayeva and Pavel Medvedev
Atmosphere 2025, 16(7), 769; https://doi.org/10.3390/atmos16070769 - 23 Jun 2025
Viewed by 305
Abstract
The data on the volumetric radon activity of the Akchatau territory were systematized in the context of radioecological safety. Radon (Rn222 and Rn220) and indoor radon (isotopes Po, Pb, and Bi) make a significant contribution to radon radiation in residential [...] Read more.
The data on the volumetric radon activity of the Akchatau territory were systematized in the context of radioecological safety. Radon (Rn222 and Rn220) and indoor radon (isotopes Po, Pb, and Bi) make a significant contribution to radon radiation in residential and industrial premises. Increased radon concentration in a number of areas is associated with the Akchatau tungsten–molybdenum mine. The source of radon in geological terms is acid leucocratic granites in the northwestern and southeastern parts of the studied territory. Seasonal assessment of radon radiation was carried out using modern devices “Alfarad Plus” and “Ramon-Radon”. Frequency analysis of the average annual equivalent equilibrium concentration (EEC) in 181 premises showed that only in 47.5% of the premises does the volumetric radon activity not exceed the current standards (200 Bq/m3). Differentiated values of radon concentration were obtained in cases where daily and seasonal observations were carried out. In 43.1% of premises, the effective dose varies from 6.6 mSv/year to 33 mSv/year, and for 9.4% of premises, from 33 mSv/year to 680 mSv/year. The increased radon concentration is caused by high exhalation from the soil surface, the radioactivity of building materials, and low air exchange in the surveyed premises. In the northwestern part of Akchatau, anomalous zones were found where the exposure dose rate of gamma radiation exceeds 0.6 mkSv/hour. An objective assessment of radon largely depends on a number of factors that take into account the geological, technical, atmospheric, and climatic conditions of the region. Therefore, when planning an optimal radon rehabilitation strategy, it is necessary to take the following factors into account: the design features of residential premises and socio-economic conditions. Practical recommendations are given for radiation-ecological and hygienic monitoring of radon safety levels in the environment to reduce effective doses on the population. Full article
(This article belongs to the Section Air Quality)
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29 pages, 3636 KiB  
Article
Design, Development, and Evaluation of a Contactless Respiration Rate Measurement Device Utilizing a Self-Heating Thermistor
by Reza Saatchi, Alan Holloway, Johnathan Travis, Heather Elphick, William Daw, Ruth N. Kingshott, Ben Hughes, Derek Burke, Anthony Jones and Robert L. Evans
Technologies 2025, 13(6), 237; https://doi.org/10.3390/technologies13060237 - 9 Jun 2025
Viewed by 408
Abstract
The respiration rate (RR) is an important vital sign for early detection of health deterioration in critically unwell patients. Its current measurement has limitations, relying on visual counting of chest movements. The design of a new RR measurement device utilizing a self-heating thermistor [...] Read more.
The respiration rate (RR) is an important vital sign for early detection of health deterioration in critically unwell patients. Its current measurement has limitations, relying on visual counting of chest movements. The design of a new RR measurement device utilizing a self-heating thermistor is described. The thermistor is integrated into a hand-held air chamber with a funnel attachment to sensitively detect respiratory airflow. The exhaled respiratory airflow reduces the temperature of the thermistor that is kept at a preset temperature, and its temperature recovers during inhalation. A microcontroller provides signal processing, while its display screen shows the respiratory signal and RR. The device was evaluated on 27 healthy adult volunteers, with a mean age of 32.8 years (standard deviation of 8.6 years). The RR measurements from the device were compared with the visual counting of chest movements, and the contact method of inductance plethysmography that was implemented using a commercial device (SOMNOtouch™ RESP). Statistical analysis, e.g., correlations were performed. The RR measurements from the new device and SOMNOtouch™ RESP, averaged across the 27 participants, were 14.6 breaths per minute (bpm) and 14.0 bpm, respectively. The device has a robust operation, is easy to use, and provides an objective measure of the RR in a noncontact manner. Full article
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22 pages, 640 KiB  
Review
Innovative Approaches to Early Detection of Cancer-Transforming Screening for Breast, Lung, and Hard-to-Screen Cancers
by Shlomi Madar, Reef Einoch Amor, Sharon Furman-Assaf and Eitan Friedman
Cancers 2025, 17(11), 1867; https://doi.org/10.3390/cancers17111867 - 2 Jun 2025
Viewed by 1712
Abstract
Early detection of cancer is crucial for improving patient outcomes. Traditional modalities such as mammography and low-dose computed tomography are effective but exhibit inherent limitations, including radiation exposure and accessibility challenges. This review explores innovative, non-invasive cancer screening methods, focusing on liquid biopsy [...] Read more.
Early detection of cancer is crucial for improving patient outcomes. Traditional modalities such as mammography and low-dose computed tomography are effective but exhibit inherent limitations, including radiation exposure and accessibility challenges. This review explores innovative, non-invasive cancer screening methods, focusing on liquid biopsy and volatile organic compound (VOC)-based detection platforms. Liquid biopsy analyzes circulating tumor DNA and other biomarkers in bodily fluids, offering potential for early detection and monitoring of treatment response. VOC-based detection leverages unique metabolic signatures emitted by cancer cells, detectable in exhaled breath or other bodily emissions, providing a rapid and patient-friendly screening option. We provide a comprehensive overview of these advanced multi-cancer detection techniques to enhance diagnostic accuracy, accessibility, and patient adherence, and ultimately enhance survival rates and patient outcomes. Full article
(This article belongs to the Section Cancer Causes, Screening and Diagnosis)
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14 pages, 4397 KiB  
Article
High-Sensitivity, Low-Hysteresis, Flexible Humidity Sensors Based on Carboxyl-Functionalized Reduced-Graphene Oxide/Ag Nanoclusters
by Hongping Liang, Lanpeng Guo, Yue Niu, Zilun Tang, Zhenting Zhao, Haijuan Mei, Ru Fang, Chen Liu and Weiping Gong
Nanomaterials 2025, 15(11), 800; https://doi.org/10.3390/nano15110800 - 27 May 2025
Viewed by 453
Abstract
The measurement of humidity is of great significance for precision instruments, semiconductor integrated circuits, and element manufacturing factories. The oxygen-containing groups and noble metals in graphene-based sensing materials can significantly influence their humidity-sensing performance. Herein, 1,3,5-benzenetricarboxylic acid-functionalized reduced graphene oxide (H3BTC-rGO) loaded with [...] Read more.
The measurement of humidity is of great significance for precision instruments, semiconductor integrated circuits, and element manufacturing factories. The oxygen-containing groups and noble metals in graphene-based sensing materials can significantly influence their humidity-sensing performance. Herein, 1,3,5-benzenetricarboxylic acid-functionalized reduced graphene oxide (H3BTC-rGO) loaded with Ag nanocluster nanocomposites (H3BTC-rGO/Ag) was synthesized via a facile one-step reduction method. The H3BTC-rGO/Ag-based sensor exhibited excellent humidity-sensing performance, including a higher sensitivity of 88.9% and a faster response/recovery time of 9 s/16 s towards 50% RH than those of other GO-, rGO-, and H3BTC-rGO-based sensors. The proposed humidity sensor was tested in the range of 0% to 100% RH and showed excellent sensitivity even at a low relative humidity of 0–10% or a high relative humidity of 90–100%. In addition, the H3BTC-rGO/Ag-based sensor had excellent selectivity, reliable repeatability, and good stability over 30 days under different relative humidities. Compared with H3BTC-rGO-200, the H3BTC-rGO/Ag-0.25-based sensor exhibited a low hysteresis of less than ±5% RH. The high performance was ascribed to the high density of the carboxyl groups and good conductivity of H3BTC-rGO, as well as the catalytic role of the Ag nanoclusters, resulting in high water adsorption rates. The potential applications of the H3BTC-rGO/Ag-based humidity sensor in human exhalation monitoring are also discussed. This work provides a reference for the application of graphene-based flexible sensors in monitoring very wet and dry environments. Full article
(This article belongs to the Section 2D and Carbon Nanomaterials)
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15 pages, 3766 KiB  
Article
Improving Pulmonary Delivery of Budesonide Suspensions Nebulized with Constant-Output Vibrating Mesh Nebulizers by Using Valved Holding Chamber
by Tomasz R. Sosnowski, Izabela Kazimierczak, Aleksandra Sawczuk, Kamil Janeczek and Andrzej Emeryk
Pharmaceutics 2025, 17(6), 696; https://doi.org/10.3390/pharmaceutics17060696 - 26 May 2025
Viewed by 657
Abstract
Background: Vibrating mesh nebulizers (VMNs) are not only used to deliver typical pulmonary drugs but are also a promising platform for novel formulations and therapeutic applications. Typically, these devices operate continuously or on demand and are directly connected to the outflow interface [...] Read more.
Background: Vibrating mesh nebulizers (VMNs) are not only used to deliver typical pulmonary drugs but are also a promising platform for novel formulations and therapeutic applications. Typically, these devices operate continuously or on demand and are directly connected to the outflow interface (mouthpiece or mask) without valving systems that could spare the drug during exhalation. This paper examines the possibility of increasing the delivery of inhaled budesonide aerosol by attaching a valved holding chamber (VHC) to selected VMNs. Methods: A laboratory in vitro study was conducted for seven budesonide (BUD) nebulization products (0.25 mg/mL). The rates of aerosol delivery from VMNs alone or VMN + VHC systems were determined gravimetrically for a simulated breathing cycle, while droplet size distributions in mists were measured by laser diffraction. Results: The VMN + VHC systems increased the amount of aerosol available for inhalation and the fraction of fine particles that could penetrate the pulmonary region. Depending on the VMN and BUD product, a relative increase of 30–300% in the total drug delivery (T) and 50–350% in the pulmonary drug availability (P) was obtained. The results are explained by the reduction in aerosol losses during exhalation (the fugitive emission) by the VHC and the simultaneous elimination of the largest droplets due to coalescence and deposition in the chamber. Both VMN and BUD affected the aerosol’s properties and discharge mass and thus the actual benefits of the VHC. Conclusions: While the results confirm the superiority of VMN + VHC over VMNs alone in nebulizing BUD suspensions, they also show that it is difficult to predict the effects quantitatively without testing the individual nebulizer–chamber–drug combination. Full article
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26 pages, 19105 KiB  
Article
Comparative Analysis of Mineralogical Composition and Radioactivity Levels in Stone Samples from the Archaeological Site of Halaesa (Sicily, Italy)
by Giuseppe Paladini, Paola Cardiano, Francesco Caridi, Lorenzo Pistorino, Domenico Majolino, Francesco Gregorio, Stefania Lanza, Gabriele Lando, Antonio Francesco Mottese, Marco Miano, Olivia Gómez-Laserna and Valentina Venuti
Appl. Sci. 2025, 15(11), 5915; https://doi.org/10.3390/app15115915 - 24 May 2025
Viewed by 497
Abstract
This work presents the results of a multi-technique comparative investigation aimed at assessing the mineralogical composition and radioactivity levels of two stone fragments from different areas of the archaeological site of Halaesa (Sicily, Italy). The analysis employed an integrated approach combining μ-energy-dispersive X-ray [...] Read more.
This work presents the results of a multi-technique comparative investigation aimed at assessing the mineralogical composition and radioactivity levels of two stone fragments from different areas of the archaeological site of Halaesa (Sicily, Italy). The analysis employed an integrated approach combining μ-energy-dispersive X-ray fluorescence (μ-EDXRF) spectroscopy, µ-Raman spectroscopy, X-Ray Diffraction (XRD), ion chromatography (IC), High-Purity Germanium (HPGe) gamma spectrometry, and E-PERM electret ion chamber methods. By examining the stone composition at both the elemental and molecular scales, with support from ion chromatography data, potential degradation patterns linked to post-depositional weathering and external decay agents were identified. Moreover, the specific activity of radionuclides (226Ra, 232Th, and 40K) and the 222Rn exhalation rates were measured, enabling the estimation of a set of radiological indices that assess potential health hazards associated with prolonged exposure to these lithic materials. The findings highlight how a multidisciplinary approach can foster the assessment of stone deterioration mechanisms, supporting the design of optimized conservation strategies aimed at preserving the archaeological heritage of Halaesa and ensuring the safety of both the public and onsite personnel. Full article
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17 pages, 4189 KiB  
Article
Exhale-Focused Thermal Image Segmentation Using Optical Flow-Based Frame Filtering and Transformer-Aided Deep Networks
by Do-Kyeong Lee, Jae-Sung Shin, Jae-Sung Choi, Min-Hyung Choi and Min Hong
Bioengineering 2025, 12(5), 542; https://doi.org/10.3390/bioengineering12050542 - 18 May 2025
Viewed by 471
Abstract
Since the COVID-19 pandemic, interest in non-contact diagnostic technologies has grown, leading to increased research into remote biosignal monitoring. The respiratory rate, widely used in previous studies, offers limited insight into pulmonary volume. To redress this, we propose a thermal imaging-based framework for [...] Read more.
Since the COVID-19 pandemic, interest in non-contact diagnostic technologies has grown, leading to increased research into remote biosignal monitoring. The respiratory rate, widely used in previous studies, offers limited insight into pulmonary volume. To redress this, we propose a thermal imaging-based framework for respiratory segmentation aimed at estimating non-invasive pulmonary function. The proposed method uses an optical flow magnitude-based thresholding technique to automatically extract exhalation frames and segment them into frame sequences. A TransUNet-based network, combining a Convolutional Neural Network (CNN) encoder–decoder architecture with a Transformer module in the bottleneck, is trained on these sequences. The model’s Accuracy, Precision, Recall, IoU, Dice, and F1-score were 0.9832, 0.9833, 0.9830, 0.9651, 0.9822, and 0.9831, respectively, which results demonstrate high segmentation performance. The method enables the respiratory volume to be estimated by detecting exhalation behavior, suggesting its potential as a non-contact tool to monitor pulmonary function and estimate lung volume. Furthermore, research on thermal imaging-based respiratory volume analysis remains limited. This study expands upon conventional respiratory rate-based approaches to provide a new direction for respiratory analysis using vision-based techniques. Full article
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19 pages, 7249 KiB  
Article
Effect of Calcium Chloride on the Reinforcement of Uranium Tailings with Sodium Hydroxide–Sodium Silicate–Metakaolin
by Qianjin Niu and Xiujuan Feng
Minerals 2025, 15(5), 526; https://doi.org/10.3390/min15050526 - 15 May 2025
Viewed by 340
Abstract
The uranium tailings mineral body is large and loose, and this could lead to radioactive contamination. Nuclides and heavy metals released from uranium tailings can be reduced through reinforcement treatment. The current study investigated the effect of CaCl2 solutions with the same [...] Read more.
The uranium tailings mineral body is large and loose, and this could lead to radioactive contamination. Nuclides and heavy metals released from uranium tailings can be reduced through reinforcement treatment. The current study investigated the effect of CaCl2 solutions with the same volume and different mass fractions on uranium tailing reinforcement under the premise of fixing the dosage of metakaolin, sodium hydroxide, sodium silicate, and the water reducer. It was found that, when 20.0% CaCl2 was injected, the hydration reaction occurred more efficiently, and a more uniform gel polymer was produced. The degree of polymerization was higher, as well as the degree of aggregation near macropores. A large number of closed mesopores formed on the solidified surface. The pore structure of the solidified body was significantly improved; uranium ore particles had smaller gaps between them; the solidified body was better compacted; the leaching rates of uranium and its heavy metal ions were significantly reduced; and the compressive strength of the solidified body improved. In the triaxial test, the solidified body had a strength increase of 4.7 times. In addition to SEM, XPS, and XRD, the solidified samples were analyzed. In uranium slag solidified bodies, C-S-H and C-A-H gels and C-A-S-H and N-A-S-H polymers were formed. The gel polymers were wrapped around the uranium tailing particles, resulting in an 82.6% reduction in uranium leaching and a 57.2% reduction in radon exhalation. Full article
(This article belongs to the Section Environmental Mineralogy and Biogeochemistry)
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15 pages, 3436 KiB  
Article
Synchronization of Inhalation/Exhalation Ratio and Heart Rate Variability During Spontaneous Breathing
by Emi Yuda and Yutaka Yoshida
Electronics 2025, 14(9), 1903; https://doi.org/10.3390/electronics14091903 - 7 May 2025
Viewed by 1376
Abstract
In this study, we investigate the relationship between breathing patterns and cardiac autonomic nervous activity during spontaneous breathing. Electrocardiograms and respiratory signals were simultaneously monitored in six subjects for 5 min while in a seated position. The inhalation/exhalation ratio (i/e) was calculated, and [...] Read more.
In this study, we investigate the relationship between breathing patterns and cardiac autonomic nervous activity during spontaneous breathing. Electrocardiograms and respiratory signals were simultaneously monitored in six subjects for 5 min while in a seated position. The inhalation/exhalation ratio (i/e) was calculated, and its variance was compared with the heart rate variability index. The results showed that inhalation time tended to be longer than exhalation time, with the inhalation-to-exhalation ratio ranging from 1.074 to 1.423. Additionally, one subject exhibited an unusually slow respiratory cycle. The inhalation/exhalation ratio was partly associated with changes in the low-frequency to high-frequency ratio (LF/HF) of heart rate variability, indicating individual differences. These findings suggest that while breathing patterns play a role in autonomic nervous system regulation and may have applications in stress and respiratory health management, there are limitations to these associations. Full article
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12 pages, 1178 KiB  
Article
Natural Radioactivity Content and Radon Exhalation Rate Assessment for Building Materials from the Archaeological Park of Tindari, Sicily, Southern Italy: A Case Study
by Francesco Caridi, Giuseppe Paladini, Francesco Gregorio, Stefania Lanza, Gabriele Lando, Marco Sfacteria, Stefania Tuccinardi, Marta Venuti, Paola Cardiano, Domenico Majolino and Valentina Venuti
Int. J. Environ. Res. Public Health 2025, 22(3), 379; https://doi.org/10.3390/ijerph22030379 - 5 Mar 2025
Cited by 2 | Viewed by 662
Abstract
This paper presents a case study of the natural radioactivity level and radon exhalation in limestone and sandstone rocks from the archaeological park of Tindari, located in Sicily, southern Italy. These rocks were representative of natural stones utilised as building materials in the [...] Read more.
This paper presents a case study of the natural radioactivity level and radon exhalation in limestone and sandstone rocks from the archaeological park of Tindari, located in Sicily, southern Italy. These rocks were representative of natural stones utilised as building materials in the studied area. The activity concentrations of 226Ra, 232Th, and 40K were assessed using high purity germanium (HPGe) gamma-ray spectrometry. Subsequently, the absorbed gamma dose rate (D), annual effective dose equivalent (AEDE), activity concentration index (ACI), and alpha index (Iα) were quantified to evaluate potential radiological health risks associated with radiation exposure from the analysed rocks. Finally, E-PERM electret ion chamber measurements were conducted to accurately quantify the radon exhalation rate from the investigated samples. The results obtained in this case study provide a foundation for further research into the background radioactivity levels in natural stones employed as building materials. Full article
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9 pages, 1216 KiB  
Brief Report
Lentinan Reduces Transmission Efficiency of COVID-19 by Changing Aerodynamic Characteristic of Exhaled SARS-CoV-2 Aerosols in Golden Hamsters
by Cheng Zhang, Jiaming Li, Huan Cui, Yifei Jin, Zhaoliang Chen, Lei Zhang, Sihui Song, Bing Lu, Zhongyi Wang and Zhendong Guo
Microorganisms 2025, 13(3), 597; https://doi.org/10.3390/microorganisms13030597 - 5 Mar 2025
Viewed by 637
Abstract
Lentinan (LNT) was found to reduce the aerosol transmission rate between golden hamsters from 100% (9/9) to 44.4% (4/9). The viral loads in the respiratory system, including the nasal turbinate, trachea, and lung, were significantly reduced in the infected golden hamsters that received [...] Read more.
Lentinan (LNT) was found to reduce the aerosol transmission rate between golden hamsters from 100% (9/9) to 44.4% (4/9). The viral loads in the respiratory system, including the nasal turbinate, trachea, and lung, were significantly reduced in the infected golden hamsters that received LNT treatment. Furthermore, the amount of exhaled virus aerosols in hamsters treated with LNT was significantly lower than that in untreated hamsters throughout the entire disease progression. In detail, the amounts of virus-laden particles with aerodynamic diameters less than 5 µm exhibited a significant decreasing trend following LNT treatment. Moreover, the detection rate of infectious SARS-CoV-2 in each stage of the Anderson-6 sampler exhibited a decreasing trend following LNT treatment post-infection. In summary, our findings indicate that LNT therapy represents a promising therapeutic candidate for the treatment of COVID-19 patients. Meanwhile, during the course of treatment, LNT has the potential to reduce viral infectivity in affected individuals. Full article
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17 pages, 3304 KiB  
Article
Evaluation of In-Ear and Fingertip-Based Photoplethysmography Sensors for Measuring Cardiac Vagal Tone Relevant Heart Rate Variability Parameters
by Ankit Parikh, Gwyn Lewis, Hamid GholamHosseini, Usman Rashid, David Rice and Faisal Almesfer
Sensors 2025, 25(5), 1485; https://doi.org/10.3390/s25051485 - 28 Feb 2025
Viewed by 1335
Abstract
This paper presents a study undertaken to evaluate the sensor systems that were shortlisted to be used in the development of a portable respiratory-gated transcutaneous auricular vagus nerve stimulation (taVNS) system. To date, all published studies assessing respiratory-gated taVNS have been performed in [...] Read more.
This paper presents a study undertaken to evaluate the sensor systems that were shortlisted to be used in the development of a portable respiratory-gated transcutaneous auricular vagus nerve stimulation (taVNS) system. To date, all published studies assessing respiratory-gated taVNS have been performed in controlled laboratory environments. This limitation arises from the reliance on non-portable sensing equipment, which poses significant logistical challenges. Therefore, we recognised a need to develop a portable sensor system for future research, enabling participants to perform respiratory-gated stimulation conveniently from their homes. This study aimed to measure the accuracy of an in-ear and a fingertip-based photoplethysmography (PPG) sensor in measuring cardiac vagal tone relevant heart rate variability (HRV) parameters of root mean square of successive R-R interval differences (RMSSDs) and the high-frequency (HF) component of HRV. Thirty healthy participants wore the prototype sensor equipment and the gold standard electrocardiogram (ECG) equipment to record beat-to-beat intervals simultaneously during 10 min of normal breathing and 10 min of deep slow breathing (DSB). Additionally, a stretch sensor was evaluated to measure its accuracy in detecting exhalation when compared to the gold standard sensor. We used Bland–Altman analysis to establish the agreement between the prototypes and the ECG system. Intraclass correlation coefficients (ICCs) were calculated to establish consistency between the prototypes and the ECG system. For the stretch sensor, the true positive rate (TPR), false positive rate (FPR), and false negative rate (FNR) were calculated. Results indicate that while ICC values were generally good to excellent, only the fingertip-based sensor had an acceptable level of agreement in measuring RMSSDs during both breathing phases. Only the fingertip-based sensor had an acceptable level of agreement during normal breathing in measuring HF-HRV. The study highlights that a high correlation between sensors does not necessarily translate into a high level of agreement. In the case of the stretch sensor, it had an acceptable level of accuracy with a mean TPR of 85% during normal breathing and 95% during DSB. The results show that the fingertip-based sensor and the stretch sensor had acceptable levels of accuracy for use in the development of the respiratory-gated taVNS system. Full article
(This article belongs to the Special Issue Multiple Sensor Signal and Image Processing for Clinical Application)
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17 pages, 1482 KiB  
Review
Eosinophil-Driven vs. Eosinophil-Associated Severe Asthma: Practical Implications for Target Treatment
by Valentina D’Aiuto, Ilaria Mormile, Francescopaolo Granata, Antonio Romano, Francesca Della Casa, Gabriele Mignogna, Amato de Paulis and Francesca Wanda Rossi
Int. J. Mol. Sci. 2025, 26(4), 1729; https://doi.org/10.3390/ijms26041729 - 18 Feb 2025
Cited by 1 | Viewed by 2302
Abstract
Severe asthma (SA) is a chronic inflammatory condition affecting approximately 10% of asthmatic patients, and eosinophils are considered key pathogenetic actors in a significant number of patients. Biological therapies have been demonstrated to improve asthma control by decreasing exacerbation rates and reducing the [...] Read more.
Severe asthma (SA) is a chronic inflammatory condition affecting approximately 10% of asthmatic patients, and eosinophils are considered key pathogenetic actors in a significant number of patients. Biological therapies have been demonstrated to improve asthma control by decreasing exacerbation rates and reducing the use of oral corticosteroids. In this context, phenotyping and endotyping patients with SA is essential for selecting the most effective therapeutic approach. For this purpose, biomarkers such as IgE, absolute blood eosinophil count, and fractional exhaled nitric oxide (FeNO) are crucial in defining a patient’s inflammatory profile. Their integration provides a framework for classifying asthma into T2-high, T2-mild, or T2-low categories, guiding personalized treatment strategies. By incorporating multiple biomarkers into a unified model, it is possible to better stratify patients and optimize biologic therapy selection, paving the way for improved outcomes in SA management. This review aims to evaluate the role of phenotyping and endotyping SA patients, with particular attention to the impact of eosinophilic inflammation and combinatory biomarkers on decision-making processes for the selection of biological therapies. Full article
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20 pages, 1551 KiB  
Article
Capnometry-Guided Respiratory Intervention in Veteran PTSD: Impact on Symptom Clusters
by Robert N. Cuyler, Juliette S. Mojgani, Julio Cezar Albuquerque da Costa and Rafael C. Freire
Healthcare 2025, 13(4), 390; https://doi.org/10.3390/healthcare13040390 - 11 Feb 2025
Viewed by 1141
Abstract
Background/Objectives: Post-traumatic stress disorder (PTSD) is a challenging psychiatric condition to treat, with suboptimal recovery and difficulty tolerating exposure-based psychotherapies often noted in outcomes research. The aim of this study was to examine patterns of symptom reduction in veterans with PTSD treated with [...] Read more.
Background/Objectives: Post-traumatic stress disorder (PTSD) is a challenging psychiatric condition to treat, with suboptimal recovery and difficulty tolerating exposure-based psychotherapies often noted in outcomes research. The aim of this study was to examine patterns of symptom reduction in veterans with PTSD treated with a Capnometry-Guided Respiratory Intervention (CGRI), a 28-day treatment teaching about the normalization of respiratory rate and exhaled carbon dioxide levels via biofeedback. We hypothesized reductions in total PCL-5 scores and all symptom clusters immediately post-treatment but with relative resistance to changes in hyperarousal symptoms, as reported in the outcomes of research using other evidence-based psychotherapies. Methods: In this report of real-world outcomes, we included 164 veterans treated with CGRI. Pre- and post-treatment PTSD Checklists for DSM-5 (PCL-5) scales were recorded and analyzed based on the total, cluster, and item scores. Subjects were additionally classified into Recovered, Improved, or Suboptimal subgroups based on their response to treatment. Data were compiled during routine clinical care and are available for retrospective analysis. Results: Treatment response was reported in 53% of participants, with a mean total PCL-5 score reduction of 12 points post-treatment (effect size, Glass’s Δ = 0.99, large) and individual PCL-5 clusters showing medium to large effect sizes (effect size = 0.71 to 0.98). Contrary to our hypothesis, a large effect size was found in the hyperarousal cluster, with post-treatment scores being significantly improved compared to pre-treatment scores (effect size = 0.98). In the Recovered group, all 20 PCL-5 items showed significant declines, while significant reductions were reported in some items in the Improved group and no item improvements were noted in the Suboptimal group. Conclusions: Consistently with prior published trials reporting overall improvements in PTSD symptoms, in this report, the CGRI produced clinically meaningful reductions in PCL-5 cluster scores in addition to total scores. Unlike reports from several trials of cognitive therapies, this study found hyperarousal symptoms to be responsive to treatment. The CGRI shows evidence of improvement across the range of PTSD symptoms in the immediate post-treatment interval. The absence of an extended post-treatment follow up introduces uncertainty concerning the durability of benefits experienced, although previous CGRI research on both panic disorder and PTSD has shown the maintenance of symptom reduction in six- to twelve-month intervals. Full article
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