Search Results (196)

While intermittent desaturations are a common occurrence in near-term and term infants, these may not be benign events with fluctuations in oxygen saturation associated with later neurodevelopmental impairment. Further, intermittent desaturation events do not necessarily result in intermittent hypoxia (IH). Polysomnography is the gold standard to diagnose intermittent desaturations in infants; however, it remains an expensive, inaccessible test. Therefore, overnight oximetry; an economical and more readily available test, is routinely used in this population. Overnight oximetry employs measurement of peripheral cutaneous arterial oxygen saturation (SpO₂) alone to inform clinical management of intermittent desaturations. Management strategies include discharging near-term and term infants on low-flow long-term oxygen therapy (LTOT), typically for upwards of six months. Oxygen saturation targets for neonates have been widely studied. However, interpretation of overnight oximetry is problematic due to a lack of established reference ranges with current approaches still based on limited evidence. This raises questions of the clinical relevancy of overnight oximetry in infants for diagnosing IH and the resultant need for LTOT. Given the association between IH and later neurodevelopmental impairment, concurrent measurement of cerebral tissue oxygen saturation by near-infrared spectroscopy (NIRS) may better identify those near-term and term infants in need of LTOT. Here we review the emerging evidence for the clinical use of cerebral NIRS and the relevance of overnight oximetry in identifying IH in near-term and term newborns and its potential role in identifying those requiring LTOT. Full article

This paper presents a CMOS-based hybrid system capable of noninvasively quantifying the total hemoglobin (tHb), the oxygen saturation (SpO₂), and the heart rate (HR) by utilizing five-wavelength (670, 770, 810, 850, and 950 nm) photoplethysmography. Conventional pulse oximeters are limited to the measurements of SpO₂ and heart rate, therefore hindering the real-time estimation of tHb that is clinically essential for monitoring anemia, chronic diseases, and postoperative recovery. Therefore, the proposed hybrid system enables us to distinguish between the concentrations of oxygenated (HbO₂) and deoxygenated hemoglobin (Hb) by using the absorption characteristics of five wavelengths from the visible to near-infrared range. This CMOS hybrid mixed-signal architecture includes a light emitting diode (LED) driver as a transmitter and an optoelectronic receiver with on-chip avalanche photodiodes, followed by a field-programmable gate array (FPGA) for a real-time signal processing pipeline. The proposed hybrid system, validated through post-layout simulations and algorithmic verification, achieves high precision with ±0.3 g/dL accuracy for tHb and ±1.5% for SpO₂, while the heart rate is extracted via 1024-point Fast Fourier Transform (FFT) with an error below ±0.2%. These results demonstrate the potential of a CMOS-based hybrid system as a feasible solution to achieve real-time, low-power, and high-accuracy analysis of bio-signals for clinical and home-use applications. Full article

Background/Objectives: The maintenance of cerebral blood flow (CBF) by managing blood pressure and brain cell activity and avoiding hypocapnia is important when administering anesthesia to patients with dementia. This study aimed to evaluate CBF during general anesthesia in elderly patients with severe dementia while maintaining their physiological parameters within an adequate range. Methods: The patients were anesthetized within a set range of parameters without affecting CBF (mean arterial pressure [MAP] > 50 mmHg; bispectral index [BIS] > 20; percutaneous arterial oxygen saturation [SpO₂] > 95%; end-tidal CO₂ [etCO₂] 35–40 mmHg). The normalized tissue hemoglobin index (nTHI), which reflects CBF, was measured using near-infrared spectroscopy. The parameters were compared between patients with severe dementia (n = 13) and those without cognitive impairment (n = 13). Results: There were no differences in patient background. A similar decline in MAP and BIS values was observed in both groups, but the values remained within the set range. The nTHI decreased significantly to 0.60 in the dementia group and to 0.79 in the non-dementia group after the start of the treatment (p ≤ 0.049). Even when the MAP, BIS, SpO₂, and etCO₂ values were maintained in their adequate ranges during general anesthesia, the nTHI decreased by 40% in the dementia group. Conclusions: These findings indicate that CBF greatly decreases in elderly patients with severe dementia during general anesthesia. Full article

This study investigates the impacts of the gas environment, water matrix, and reactive species on the TiO₂-mediated photocatalytic degradation of safranin O (SO), a dye commonly found in wastewater. A slurry reactor (UVA, 365 nm) was used to quantify SO oxidation while systematically varying the SO concentration (5–40 mg/L), the TiO₂ loading (0–3 g/L), the temperature (15–45 °C), and the pH (2–12). The dissolved gases (air, nitrogen, and argon) and matrices (deionized water, mineral water, and seawater) were also examined. Eight mechanistic probes (ascorbic acid, methanol, azide, nitrite, benzoquinone, oxalate, sucrose, and phenol) were used to identify active oxidants. UVA/TiO₂ achieved rapid decolorization in approximately 90 min at 10 mg/L of SO and 0.4 g/L of TiO₂. Decolorization rates decreased with increasing SO concentration due to active-site competition and inner-filter effects. Rates also exhibited a bell-shaped dependence on TiO₂ loading due to light scattering and aggregation at high solids concentrations. Temperature exhibited a non-monotonic profile with an optimum around 25 °C, and the pH displayed an optimum range with maximal removal occurring around pH 10 and declining at pH 12. Air saturation outperformed N₂ and Ar, indicating that O₂ is the terminal electron acceptor. Photocatalytic performance decreased in the order deionized water > mineral water > seawater, owing to bicarbonate/chloride scavenging and ionic-strength effects. Scavenger tests converged on ^•OH dominance, with measurable contributions from superoxide/hydrogen peroxide (O₂^•−/H₂O₂) and valence-band holes (h⁺); singlet oxygen (¹O₂) played a minor role. These findings underscore the critical interplay between operational and environmental factors and offer a practical framework for scaling TiO₂-based SO abatement in real waters. Full article

Wearable technology is rapidly evolving, with increasing efforts to integrate a wide range of sensors capable of capturing real-time physiological and behavioral health data from users. These devices have shown significant promise in supporting health monitoring and promoting well-being by providing continuous, objective feedback based on data analytics. Importantly, they enable early detection of potential health issues, allowing for timely intervention and more personalized healthcare. While a wide variety of commercially available wearable devices are designed for adults—tracking metrics such as physical activity, heart rate, body temperature, electrocardiograms (ECG), and oxygen saturation—there remains a notable gap in the availability and development of wearable technologies specifically tailored to the pediatric population. This narrative review paper focuses on non-invasive wearable technologies developed for individuals under the age of 18, with an emphasis on health-related applications. We examine the current landscape of pediatric wearable research, including devices aimed at monitoring developmental progress and chronic health conditions. Particular attention is given to the limited research on wearables for younger children, where physiological and developmental differences pose additional challenges. Furthermore, we explore emerging applications, identify key barriers to adoption, and discuss opportunities for future development, including improvements in design, data privacy, and age-appropriate functionality. Full article

Pulsatile signal detection plays an important role in monitoring various physiological parameters, primarily heart rate and blood oxygen saturation. Their applications range from clinical settings to personal health and wellness monitoring. PPG (photoplethysmography) can provide non-invasive optical measurements to detect blood volume changes in peripheral tissues. Yet, it suffers from low spatial resolution to precisely detect the pulsatile signal originating over 2 mm in human tissue. Ultrasound (US) provides a deep detectable range compared to the pure optical method. However, its low contrast to red blood cells and cluster artifacts makes it only detect the indirect pulsation from the surrounding tissue of blood vessels. Recent advances in PA imaging show its capability to precisely measure pulsatile signals originating from blood vessels in deep regions (over 10 mm) and its potential to accurately record blood oxygen saturation with high spatial and temporal resolution. This review article summarizes studies on photoacoustic (PA) pulsatile signal monitoring, highlights the technical advances, and compares it against optical and ultrasonic approaches. Full article

Background: Weekend presentation to the emergency department (ED) has been associated with increased morbidity and mortality in various clinical settings. However, the literature is scant whether such an effect exists for patients presenting with COVID-19 infection. Additionally, comparative analyses of mortality predictors in COVID-19 patients evaluated at the emergency department need further exploration. Methods: This retrospective cohort study examined factors associated with mortality among adult patients (aged ≥ 18 years) who presented with COVID-19 to the emergency departments of five hospitals within the Johns Hopkins Health System (combined capacity: 2513 beds) between March 1 and 4 May 2020. Data were extracted from electronic health records. Multivariable logistic regression was utilized to assess the relationship between mortality and a range of variables, including sociodemographic characteristics, clinical presentation, laboratory parameters, pre-existing comorbidities, and weekend versus weekday presentation. Results: Of the 2767 patients, 685 (25%) presented to the emergency department on weekends. Compared to weekday presenters, weekend patients were more likely to be hospitalized (64%), and these patients had a mean symptom duration of 5 days (SD ± 6). Weekend presenters also exhibited higher rates of clinical frailty, dehydration, hypoxia, and respiratory distress upon arrival. In multivariable logistic regression analysis adjusting for sociodemographic characteristics, clinical risk factors, and laboratory findings, independent predictors of increased mortality included absence of a primary care provider (OR 3.47; 95% CI: 2.37–5.07), peripheral oxygen saturation (SpO₂) < 95% at presentation (OR 1.46; 95% CI: 1.001–2.12), and hyperglycemia (OR 2.13; 95% CI: 1.25–3.65). Notably, the presence of crackles on physical examination demonstrated a trend toward reduced mortality (OR 0.47; 95% CI: 0.24–0.92). Conclusions: While weekend presentation was associated with higher hospitalization rates among patients with COVID-19, it did not independently predict increased mortality. Absence of a primary care provider, hypoxia, and hyperglycemia at presentation emerged as strong, independent predictors of mortality in the ED setting. Race, gender, and obesity were not significantly associated with mortality in this cohort, warranting further investigation. These findings may support more effective triage and risk stratification strategies in current and future public health emergencies. Full article

This study aims to investigate the vibrational, structural, morphological, optical, and magnetic properties of Zn_1−xCo_xO with 0.00 ≤ x ≤ 0.05 prepared by the sol–gel method via an amorphous citrate precursor. FTIR spectroscopy was used to follow the thermal decomposition process of the ZnO precursor, identifying acetate zinc as the intermediate main component. XRD and FTIR-ATR techniques showed only the single wurtzite crystalline phase with the presence of oxygen deficiency and/or vacancies, and secondary phases were not detected. SEM micrographs showed agglomerated particles of irregular shape and size with a high distribution and evidenced particles of nanometric size with a morphology change for x = 0.05. We detected high–spin Co²⁺ ions located in the tetrahedral core and pseudo–octahedral surface sites, substituting Zn²⁺ ions. The energy band gap of the ZnO semiconductor decreased gradually when the Co doping concentration was increased. M vs. H for undoped ZnO nanoparticles exhibited a diamagnetic signal overlapped with a weak ferromagnetic signal at room temperature. Interestingly, temperature-dependent magnetization showed superparamagnetic behavior with a blocked state in the low temperature range. The Co–doped ZnO samples evidenced a weak ferromagnetic signal and a paramagnetic component, which increased with x. The saturation magnetization increased until x = 0.03 and then decreased for x = 0.05, while the coercive field gradually decreased. Full article

Laser cladding rapid solidification technique is an effective strategy for manufacturing ultra-high-strength martensitic stainless steels (UHS-MSS). Due to super-saturation solution strengthening of interstitial atoms (IAs), martensitic stainless steels containing IAs exhibit excellent ultra-high strength and toughness and have high tolerance for oxygen impurities. Hence, studying the specific speciation and structural characteristics of IAs is of great significance for guiding laser cladding of ultra-high-strength steels. Herein, we use density functional theory (DFT) computations to analyze the stable occupancies of IAs and their interactions in body-centered cubic iron (BCC Fe). The findings show that single IAs prefer to occupy octahedral sites over tetrahedral sites. Therefore, octahedral sites are selected as the optimal sites for the following double IAs study. For homo IAs, C-C and N-N configurations exhibit greater stability at long-range distances, whereas O-O demonstrate optimal stability at intermediate distances. Crucially, hetero IAs configurations are more stable compared to single IAs and homo IAs, exhibiting a synergistic effect. Especially, the C-O combination shows the highest stability and strongest bonding character. Meanwhile, the dissociation behavior of O indicates that C-O and N-O have higher dissociation temperatures than single O, further verifying the synergistic effect of hetero IAs. This provides a theoretical basis for understanding the interstitial solution strengthening of laser cladding UHS-MSS. Full article

Cardiorespiratory fitness is a predictor of long-term health, traditionally assessed through structured exercise protocols that require maximal effort and controlled laboratory conditions. These protocols, while clinically validated, are often inaccessible, physically demanding, and unsuitable for unsupervised monitoring. This study proposes a non-invasive, unsupervised alternative—predicting the heart rate a person would reach after completing the step test, using wearable data collected during natural daily activities. Ground truth post-exercise heart rate was obtained through the Queens College Step Test, which is a submaximal protocol widely used in fitness settings. Separately, wearable sensors recorded heart rate (HR), blood oxygen saturation, and motion data during a protocol of lifestyle tasks spanning a range of intensities. Two machine learning models were developed—a Human Activity Recognition (HAR) model that classified daily activities from inertial data with 96.93% accuracy, and a regression model that estimated post step test HR using motion features, physiological trends, and demographic context. The regression model achieved an average root mean squared error (RMSE) of 5.13 beats per minute (bpm) and a mean absolute error (MAE) of 4.37 bpm. These findings demonstrate the potential of test-free methods to estimate standardized test outcomes from daily activity data, offering an accessible pathway to infer cardiorespiratory fitness. Full article

Sedation and anesthesia are essential for ensuring animal welfare during surgical procedures such as hernia repair in swine. However, the number of sedative and anesthetic agents officially approved for livestock use remained limited. This study evaluated the sedative efficacy and serotonergic effects of a romifidine/ketamine/diazepam protocol, with and without the addition of tramadol, in swine undergoing umbilical hernia repair. Sixty-six crossbred Large White swine were randomly allocated to three groups: LL (lidocaine 4 mg/kg by infiltration), LT (lidocaine 2 mg/kg by infiltration + tramadol 2 mg/kg intraperitoneally), and TT (lidocaine2 mg/kg by infiltration + tramadol 4 mg/kg intraperitoneally). The physiological parameters heart rate, arterial pressure, oxygen saturation, rectal body temperature, and respiratory rate were assessed. The depth of intraoperative anesthesia and postoperative sedation was assessed using an ordinal scoring system (0–3). Plasma serotonin (5-HT) concentration was measured at baseline and 24 h post-surgery. Physiological parameters remained within species-specific reference ranges throughout the procedure. Anesthesia depth scores significantly decreased over time in all groups (p ≤ 0.001), with the tramadol-treated groups (LT and TT) showing more prolonged deeper anesthesia. Postoperative sedation was significantly higher in the TT group (p ≤ 0.001). Serotonin concentration decreased in LL, increased in LT, and remained stable in TT. These findings suggest that tramadol may enhance sedation and recovery, potentially through serotonergic modulation. Moreover, serotonin could serve as a physiological marker warranting further investigation in future studies of anesthetic protocols in veterinary medicine. Full article

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. Grape clusters were manually harvested and fermented under controlled conditions, applying micro-oxygenation treatments at two fermentation stages (day 3 and day 13) within a hyperbaric chamber. Physicochemical analyses, CIELab color measurements, visible reflectance spectra, GC-FID volatile profiling, and descriptive sensory analysis were performed. Micro-oxygenated samples (M1_MOX and M2_MOX) showed significant increases in lightness (L*), redness (a*), chroma (C*), and reflectance in the 520–620 nm range, indicating enhanced extraction and stabilization of phenolic pigments. Volatile analysis revealed that these samples also contained higher concentrations of key esters and terpenes associated with fruity and floral notes. Sensory evaluation confirmed these findings, with MOX-treated wines displaying greater aromatic intensity, flavor persistence, and varietal character. Control samples (M1_CON and M2_CON) exhibited lower color saturation and volatile compound content, along with diminished sensory quality. These results suggest that hyperbaric micro-oxygenation is an effective strategy for improving color intensity and aromatic complexity during red wine fermentation under controlled, non-thermal conditions. Full article

(1) Background: Previous studies indicate that individuals who engage in regular physical activity have a higher pain threshold than those who do not exercise. However, it remains unclear how this phenomenon behaves in individuals exposed to chronic hypoxia. This study evaluates pain perception at high altitude between high-altitude natives who exercised regularly and those who did not practice physical activity. (2) Methods: Eighty-four healthy volunteers aged 20 to 30 years old with a body mass index (BMI) within the normal range (18.5–24.9) residing in the city of Puno (3825 m) were recruited. The unilateral ischemia pain provocation test was used, applying pressure with a manual sphygmomanometer to generate transient ischemia in the arm while the patient opens and closes their hand. Onset, peak, and resolution times of pain, heart rate, and oxygen saturation were recorded. (3) Results: The average time to pain onset in the right arm was 30.2 s ± 14.1 during light physical activity, whereas, during moderate physical activity, it increased to 32.5 s ± 15.4. In the left arm, the average time until pain sensation was 27.9 s ± 16.8 during light physical activity and increased to 34.6 s ± 18.5 with moderate physical activity. Regarding the progression of pain intensity, the average time to reach unbearable pain in the right arm was 54.1 s ± 16.4 during light physical activity and 53.8 s ± 19.6 during moderate physical activity; in the left arm, it was 53.0 s ± 19.6 during light physical activity, increasing to 59.3 s ± 24.5 during moderate physical activity. (4) Conclusions: A more stable and slightly higher pain tolerance in the dominant arm was observed. Full article

Background: Acute heart failure (AHF) is a major cause of hospitalizations, posing significant challenges to healthcare systems. Despite advancements in management, the rate of poor outcomes remains high globally, emphasizing the need for timely interventions. This study aimed to identify early admission-based factors predictive of poor outcomes in hospitalized AHF patients, in order to contribute to early risk stratification and optimize patient care. Methods: This retrospective single-center study analyzed routine data of adult patients hospitalized for AHF at a public university teaching hospital in Switzerland. Outcomes included in-hospital death, intensive care (ICU) treatment, and length of hospital stay (LOHS). Potential predictors were limited to routine parameters, readily available at admission. Missing predictor data was imputed and predictors were identified by means of multivariable regression analysis. Results: Data of 638 patients (median age 84 years, range 45–101 years, 50% female) were included in the study. In-hospital mortality was 7.1%, ICU admission rate 3.8%, and median LOHS was 8 days (IQR 5–12). Systolic blood pressure ≤ 100 mmHg (Odds ratio (OR) 3.8, p = 0.009), peripheral oxygen saturation ≤ 90% or oxygen supplementation (OR 5.9, p < 0.001), and peripheral edema (OR 2.7, p = 0.044) at hospital admission were identified as predictors of in-hospital death. Furthermore, a stroke or transient ischemic attack in the patient’s history (OR 3.2, p = 0.023) was associated with in-hospital death. ICU admission was associated with oxygen saturation ≤ 90% or oxygen supplementation (OR 22.9, p < 0.001). Factors linked to longer LOHS included oxygen saturation ≤ 90% or oxygen supplementation (IRR 1.2, p < 0.001), recent weight gain (IRR 1.1, p = 0.028), and concomitant chronic kidney disease (IRR 1.2, p < 0.001). Conclusions: This study validated established predictors of AHF outcomes in a Swiss cohort, highlighting the predictive value of poor perfusion status, fluid overload, and comorbidities such as chronic kidney disease. The identified predictors imply potential for developing tools to improve rapid treatment decisions. Future research should focus on the prospective external validation of the identified predictors and the design and validation of risk scores, incorporating these parameters to optimize early interventions and reduce adverse outcomes in AHF. Full article

Background/Objectives: Adaptation to extrauterine life is challenging for preterm newborns. Environmental stimuli, such as noise, can lead to adverse health outcomes, causing instability of vital parameters and impairment of neurodevelopment. The American Academy of Pediatrics recommends a maximum environmental noise level of 45 decibels (dB) or less in the NICU. The study’s primary aim was to describe environmental noise in a neonatal intensive care unit and to analyze potential associations between noise and vital parameters of preterm newborns, including heart rate, respiratory rate, and oxygen saturation levels. Methods: A pilot observational feasibility study was conducted in a level III NICU. Sound levels and vital parameters were recorded over four hours for each preterm newborn. Confounding variables were controlled. Data were analyzed using descriptive statistics, Kendall’s τ-b, and logistic regression analysis. Ethical approval and parental consent were obtained. Results: The average environmental noise level was consistently above 45 dB. Six patients were enrolled, and 22 recordings (ranging in length from 1 to 4 h) were performed. Data adjusted for confounding variables show a statistically significant Kendall’s correlation between heart rate and decibels (τ-b = 0.89, p = 0.003, n = 520), suggesting a monotonous crescent tendency between these two variables, although the relationship is not strong. The logistic regression model indicates that the odds ratio (OR) for decibels related to tachycardia is 1.066, meaning that for each 1 dB increase, the probability of tachycardia rises by 6.6% (p < 0.001). Conversely, the OR for respiratory rate is 0.959, suggesting that for each unit increase in respiratory rate, the probability of tachycardia decreases by approximately 4.1% (p < 0.001). Conclusions: The study reveals that the mean environmental noise level in the NICU consistently exceeds the recommended safety level. Decibels are one of the significant variables contributing to the likelihood of tachycardia, and an increase in decibels has a significant effect on this, but it is not the only one. Further analysis of a larger sample is needed. Full article