Minimum Oxygen Research Articles

Enhanced removal of emerging recalcitrant pharmaceutical contaminants through integrated anaerobic and photocatalytic treatment

This study integrated anaerobic digestion (AD) and heterogenous photocatalysis, an advanced oxidation process (AOP), to treat tetracycline (TC), an emerging recalcitrant contaminant. The integrated system comprising an annular photocatalytic reactor and bioreactor was fed with simulated wastewater containing TC. The photocatalytic treatment was aided by a nano-engineered composite catalyst containing titanium dioxide (TiO2) and multi-wall carbon nanotubes (MWCNT). Heterogeneous photocatalysis as a single approach resulted in 90% TC degradation, 39% chemical oxygen demand (COD) reduction, 28% total organic carbon (TOC) removal, and minimal biochemical oxygen demand (BOD5) reduction. AD on its own removed 56% and 52%, respectively of the COD and BOD5. When applied as a pretreatment, heterogenous photocatalysis improved the biodegradability (BOD5/COD ratio) from 0.12 to 0.42 resulting in improved COD, BOD5, and TOC removals of 71%, 70%, and 76%, respectively in the ensuing AD process. Kinetic studies revealed that the ratio of the photocatalytic reactor unit to the anaerobic reactor unit for an integrated system with constant feed flow should be 12:1. Photodegradation as the only form of treatment used more energy than the integrated approach. The bioenergy generated by AD could supply the energy needs of the sequential system resulting in 20% energy savings and a carbon dioxide emission reduction (CER) of 22.74 kg for every cubic meter of treated wastewater. An integrated AOP-AD approach is thus promising for treating recalcitrant organic contaminants of emerging concern.

Comparative effectiveness of therapies for sleep-disordered breathing in heart failure patients: A comprehensive systematic review and network meta-analysis.

The prevalence of sleep-disordered breathing (SDB) in patients with heart failure (HF) is a significant concern, leading to adverse outcomes. This network meta-analysis (NMA) is dedicated to evaluate the relative effectiveness of diverse therapeutic approaches for SDB treatments in the context of HF. An extensive search up to May 19, 2023, was implemented in PubMed, Cochrane, Embase, and Web of Science to identify randomized controlled trials (RCTs). These trials compared adaptive servo ventilation (ASV), automatic positive airway pressure (APAP), Bi-level positive pressure ventilation (Bi-level PPV), continuous positive airway pressure (CPAP), and oxygen therapy against placebo or standard treatment. Key outcomes included cardiac function indicators (left ventricular ejection fraction [LVEF], plasma B-type natriuretic peptide [BNP] levels), polysomnography data (apnea-hypopnea index [AHI], Mean and Minimum Oxygen Saturation), and patient-reported quality of life measures (Epworth sleepiness scale [ESS]). A random-effects Bayesian NMA was utilized to evaluate and compare the efficacy of these interventions. The study revealed significant therapeutic effects of different interventions in sleep apnea patients. For patients with obstructive sleep apnea (OSA), CPAP demonstrated superior efficacy in enhancing average oxygen saturation (mean difference (MD)=0.98; 95% credible interval (CI) [0.07,2.09]), improving LVEF (MD=5.66; 95% CI [0.71, 10.08]), and reducing AHI (MD=-20.61; 95% CI [-33.84, -9.9]). In the case of central sleep apnea (CSA), the therapeutic approaches showed varying degrees of effectiveness. CPAP proved most effective for enhancing average oxygen saturation(MD=1.1; 95% CI [0.26,1.98]). ASV was the most effective in lowering AHI (MD=-32.11; 95% CI [-47.5, -17.16]), increasing lowest oxygen saturation (MD=8.14; 95% CI [1.72,14.92]), and enhancing LVEF (MD=6.58; 95% CI [0.06,12.49]). No single SDB treatment uniformly benefits all clinical indicators in SDB and HF patients.

Transoral Drug-Induced Sleep Endoscopy: A Useful Complementary Tool in Sleep Surgery.

Introduction Drug-induced sleep endoscopy (DISE) is performed widely, and several studies have demonstrated its validity as it provides clinical information not available by routine clinical inspection alone. Objective This study aims to evaluate the role of transoral drug-induced sleep endoscopy (DISE) in the evaluation of tongue-palate (TP) interaction and its impact on surgical outcomes. Methods A total of 42 patients with known obstructive sleep apnea syndrome (OSAS) were classified into two groups according to TP interaction (the absence of space between tongue and palate with the visual impression that the tongue is pushing the soft palate) into +ve and -ve TP interaction. Snoring according to the visual analogue scale (VAS), the Epworth Sleepiness Scale (ESS), and sleep study data were recorded before and after the pharyngoplasty operation. Results There was a statistically significant difference between studied groups postoperative regarding minimal oxygen saturation, snoring index, apnea-hypopnea index (AHI), the ESS, and visual analogue scale of snoring ( p = 0.003*, p < 0.001*, p < 0.001*, p = 0.004*, and p = 0.003*, respectively). It displayed a marked higher average improvement among cases with -ve than in those with +ve TP interaction in terms of snoring index, AHI, and ESS. Conclusion The Transoral DISE Has A Valuable Role In Evaluating And Assessing TP Interaction And Its Importance On Surgical Outcomes. Cases With Positive TP Interaction Show Poor Response To Isolated Palatopharyngeal Expansion And Need Further Analysis To Create A Better Treatment Plan And Improve Outcomes.

Green Evolution: Advancing Epoxy Composite Materials with Durian Peel Fiber Innovation

This study explores the transformative effects of treating durian peel fibers with Ca(OH)2 solution and their subsequent application as a reinforcing agent in epoxy composite materials. Morphological and structural analyses reveal a notable improvement in compatibility and adhesion between treated fibers and epoxy resin, particularly at a 5 % Ca(OH)2 concentration. Durian fruit peel, after being treated with clear lime water (Ca(OH)2), is used to reinforce the epoxy composite material at the ratio of epoxy/durian fiber peel = 70/30. The results were established when durian peel fibers treated with 5 % lime water solution had the best mechanical properties (tensile strength: 65.68 MPa, flexural strength: 92.11MPa, compressive strength: 147.38 MPa, Izod impact strength: 9.07 kJ/m2). In terms of fire retardancy, the best results were also obtained when reinforcing durian peel fibers treated with 5 % concentration of lime solution in Ca(OH)2, specifically: Minimum oxygen index: LOI = 21.9 %, Burning speed according to UL 94: 20.66 mm/min. The structural morphology of the epoxy/durian peel fiber composite was evaluated using SEM. The results demonstrated good compatibility, with no evidence of layer exfoliation or phase separation at the epoxy resin-durian peel fiber interface when subjected to external forces. The results of the project indicate that epoxy composites reinforced with durian peel fibers hold great promise as a green, environmentally friendly material. By utilizing waste from the food industry, these composites offer potential applications across various fields, including the automotive, transportation, and construction industries. HIGHLIGHTS Durian Peel Fiber Treatment: Durian peel fibers treated with 5 % Ca(OH)₂ solution for better adhesion to epoxy. Composite Reinforcement: Epoxy composite reinforced with 30 % durian peel fiber (epoxy/durian fiber = 70/30). Mechanical Properties: Best results with 5 % Ca(OH)₂-treated fibers (tensile strength: 65.68 MPa, flexural strength: 92.11 MPa, compressive strength: 147.38 MPa, impact strength: 9.07 kJ/m²). Fire Retardancy: Improved fire resistance (LOI = 21.9 %, burning speed: 20.66 mm.min-1). Applications: Promising for use in automotive, transportation, and construction industries. GRAPHICAL ABSTRACT

The Development of Algorithms for Individual Ranges of Body Temperature and Oxygen Saturation in Healthy and Frail Individuals.

Individual habitual conditions entail a risk during the interpretation of vital parameters. We developed algorithms for calculating, validating, and interpreting individual normal ranges of body temperature and oxygen saturation. In total, 70 healthy individuals aged 27 to 80 and 52 frail individuals aged 60 to 100 were included. Data on individual conditions comprised age, gender, physical ability, chronic disease, and medication. Ear temperature and oxygen saturation were measured for five mornings before the participants got out of bed and consumed medicine, food, or drink. The range for body temperature was 34.3 °C to 37.7 °C, with a variation of 0.7 °C ± 0.4 °C. The variation in minimum and maximum temperatures was 2.4 °C vs. 2.7 °C and 2.9 °C vs. 2.3 °C in healthy and frail subjects, respectively. The range for oxygen saturation was 85% to 99% in healthy individuals and 75% to 100% in frail individuals. The variation between minimum and maximum oxygen saturation was 13% vs. 25% and 4% vs. 17% in healthy and frail subjects, respectively. To promote the implementation of precision medicine in clinical practice, it is necessary to interpret body temperature and oxygen saturation based on individual habitual conditions. Interpreting deviations from an individual's normal ranges allows healthcare professionals to provide necessary treatment without delay, which can be decisive in preventing further deterioration.

Near-Infrared Spectroscopy (NIRS) to Assess Infection Complications During the Acute Phase of Acute Pancreatitis.

Acute pancreatitis (AP) severity is correlated with systemic infection incidence in the acute phase, and it is important to assess inflammation during the disease course and to recognize infection at an early stage. As in sepsis, inflammation in AP impairs tissue oxygen metabolism and disrupts microcirculation. We performed a vascular occlusion test (VOT) via near-infrared spectroscopy (NIRS), which noninvasively monitors local oxygen in peripheral tissues, to evaluate tissue oxygen metabolism and blood circulation during the acute AP phase. Tissue oxygen metabolism was measured via an NIRS probe attached to the thenar eminence at admission and 7 days after admission. The upper arm was wrapped with a sphygmomanometer cuff while avoiding brachial artery compression for 3 min. The minimum desaturation value was defined as the minimum tissue oxygen index (TOI), the maximum reactive hyperemia value after release was defined as the maximum TOI, and the difference was defined as the ∆TOI. The time from the minimum TOI to maximum TOI was defined as the TOI interval. Fifteen healthy volunteers, 13 patients with AP, and 12 patients with sepsis were included. The TOI at baseline and ∆TOI (parameter describing tissue oxygen metabolism) decreased in a stepwise manner, and the TOI interval (measure of peripheral vasodilatory capacity) was protracted in a stepwise manner among the three groups. In a subgroup analysis, no significant differences in the NIRS-derived variables between patients with AP complicated by infection and those without infection were observed at admission; however, after 7 days, the groups significantly differed. Additionally, blood lactate concentrations were significantly correlated with the ∆TOI and TOI. Mild tissue oxygen metabolism impairment and tissue perfusion occurred in AP compared with sepsis, and changes similar to those in sepsis occur in AP complicated by infection. Further research is needed to evaluate whether these values can be applied to treating this group of patients.

Differential sleep subtypes in children with OSA of different ages

ObjectiveThe aim of this study was to evaluate the variations in sleep architecture and types of sleep disturbances in preschool and school-age children diagnosed with obstructive sleep apnea (OSA). MethodsChildren who underwent polysomnography (PSG) were enrolled and divided into two groups based on age: a preschool group and a school-age group. We analyzed differences in sleep architecture and types of sleep disturbances between these groups. ResultsTotal sleep time was significantly higher in the preschool group compared to the school-age group (P < 0.05). The percentage of Stage N1 sleep (N1%) was also higher in the preschool group (p < 0.05). Conversely, the percentage of Stage N2 sleep (N2%) was lower in the preschool group (p < 0.05). Additionally, the average and minimum heart rates were higher in the preschool group, while the minimum oxygen saturation, including during non-rapid eye movement (NREM) and REM stages, was lower compared to the school-age group (P < 0.05). The prevalence of positional OSA (P-OSA) was lower, and the prevalence of REM OSA (R-OSA) was higher in the preschool group (P < 0.05). ConclusionThe prevalence of P-OSA was lower, and R-OSA was higher in preschool children compared to school-age children. Furthermore, the types of sleep disturbances in preschool children with OSA showed significant differences from those in school-age children with OSA.

New Experimental Approaches for the Determination of Flammability Limits in Methane–Hydrogen Mixtures with CO2 Inertization Using the Spark Test Apparatus

This study presents a novel experimental method to determine the flammability limits and the minimum oxygen concentration in methane–hydrogen mixtures using the spark test apparatus (STA), by incorporating CO2 as an inert compound. The proposed methodology allows for the more accurate and efficient assessment of the safety of these flammable mixtures, which is crucial for industrial applications where hydrogen-enriched fuels are used. When comparing the literature data, the differences between methods are not significant, although the procedure, apparatus, and test conditions influence the results. Then, the proposed method is experimentally validated in the STA. Methane is enriched with hydrogen at different concentrations (10, 20, 30, and 50%). The results in the STA show good alignment with the literature data. Furthermore, literature data analysis allows for the generation of an empirical curve that shows the influence of hydrogen addition in methane–air mixtures. The theoretical flammability intervals are also presented as a result. Such representations, after method validation, are the base of the flammability interval test in the STA. The capability of the STA to define flammability ranges in ternary diagrams provides an innovative graphical approach to control explosive atmospheres and facilitates its application in the prevention of industrial accidents.

High arousal threshold is associated with metabolic syndrome in patients with obstructive sleep apnea

ObjectiveObstructive sleep apnea (OSA) is associated with metabolic syndrome (MetS). OSA patients with high arousal threshold (ArTH) are less easy to arouse, which leads to more severe hypoxic events. We explored the relationship between high ArTH and MetS in patients with OSA. MethodsWe conducted a cross-sectional study of 112 patients with OSA (mean age 43.50 ± 11.64 years, 89.29 % male). High ArTH was based on an overnight polysomnography, and defined as none or one of the following conditions: apnea-hypopnea index (AHI) < 30 events/hour, minimum oxygen saturation > 82.5 %, or frequency of hypopnea events > 58.3 %. Metabolic syndrome and its components were defined according to the new International Diabetes Federation definition. ResultsAmong the 112 OSA patients, 51 (45.54 %) had MetS and 68 (60.71 %) had high ArTH. Logistic regression, after adjusting for confounders, showed that patients with high ArTH had higher odds for MetS (OR = 4.31, 95 % CI = 1.63–11.42, p = 0.003), central obesity (OR = 5.78, 95 % CI = 1.95–17.16, p = 0.002) and hypertriglyceridemia (OR = 2.84, 95 % CI = 1.11–7.28, p = 0.030) compared to patients with low ArTH. Furthermore, higher ArTH levels were associated with higher values for waist circumference (p-for-trend < 0.001), triglycerides (p-for-trend = 0.042), and systolic blood pressure (p-for-trend = 0.037). Moreover, patients with high ArTH had more apnea events and less hypopnea events. ConclusionsHigh ArTH is associated with MetS in OSA patients. High ArTH is a marker of the severity of cardiometabolic comorbidity in OSA.

The value of amide proton transfer imaging in assessing brain damage in patients with obstructive sleep apnea

ObjectiveTo investigate the application value of amide proton transfer (APT) magnetic resonance imaging in evaluating brain damage in patients with obstructive sleep apnea (OSA). Materials and methods49 OSA patients and 25 healthy individuals matched for age and sex were included as case and control groups. All study participants underwent conventional 3D T1WI and APT imaging of the head. The APT values were measured in each of the brain regions of interest (ROI). To compare the differences in APT values of each brain region between the case and control groups, to compare the differences in the efficacy of APT values of each brain region in diagnosing OSA, and to investigate the correlation between APT values of each brain region and Apnea Hypopnea Index (AHI) and minimum blood oxygen saturation. ResultsCompared to the control group, patients with OSA had elevated APT values in several brain regions (P < 0.05), and the diagnostic efficacy of the combined diagnosis of OSA by multiple brain regions is better than that by each brain region alone.Left frontal APT values were positively correlated with AHI in the case group (r = 0.33, P = 0.020).In the case group, the APT values of bilateral frontal lobe, parietal lobe, occipital lobe, left temporal lobe, right thalamus, left internal capsule, left lenticular nucleus, right cerebellar hemisphere and splenium of corpus callosum were negatively correlated with the minimum blood oxygen saturation, and the APT values for each of the above ROIs were positively correlated. ConclusionAPT imaging has a certain value in evaluating brain damage in OSA patients, which may provide a new objective imaging basis for the clinical diagnosis of OSA.

Polysomnographic and clinical characteristics of sleep apnea headache patients.

Sleep apnea headache can be defined as a persistent, widespread, throbbing headache that occurs recurrently, is not accompanied by any additional symptoms after waking up, and usually resolves within four hours. Diagnosis of the condition requires confirmation through polysomnography with an apnea-hypopnea index of at least 5, indicating the presence of obstructive sleep apnea syndrome (OSAS). While sleep apnea headaches are common in 10-15% of individuals with OSAS, morning headaches are experienced by 5% of this population. The aim of this study is to examine both polysomnographic and clinical features associated with sleep apnea headache in individuals confirmed to have OSAS by polysomnography. The study was conducted in the sleep center of University of Health Science, Erenköy Mental and Nervous Disease Training and Research Hospital. We have examined the clinical and polysomnographic data of the patients with sleep apnea headache (SAH) diagnosed according to IHS-3 criteria retrospectively and grouped the patients as mild, moderate and severe OSAS. Patients with morning headache except sleep apnea headache and under PAP titration treatment were excluded. The differences between the sleep macro structures of patients with (WSAH) and without sleep apnea headache (WOSAH) were examined. The WSAH group consisted of 384 participants and the control group (WOSAH) consisted of 294 participants The mean age was 46.29 ± 12.18 and 45.08 ± 12.62 years, respectively. Patients in the WSAH group had significantly higher scores on the Epworth Sleepiness Scale (ESS) (p = 0.004) and higher periodic limb movement index (PLMI) (p = 0.014) compared to the WOSAH group. WSAH patients exhibited shorter wake times after sleep onset (WASO) and lower scores on the sleep quality index, in contrast to WOSAH patients. Additionally, within the WSAH group, there was a negative correlation between age and several sleep parameters, including total sleep parameters. A positive correlation was observed between sleep duration (p = 0.009), waking up after sleep (p = 0.043), sleep efficiency (p = 0.001) and apnea-hypopnea index (AHI) (p = 0.018). Additionally, ESS scores were positively correlated with AHI and total awake time (p = 0.000 and p = 0.008, respectively), while negatively correlated with stage N3 sleep percentage and mean minimum oxygen level (p = 0.001 and p = 0.020, respectively) in the WSAH group. The causes and possible mechanisms of sleep apnea headache are not fully clarified and the underlying processes are not fully understood. Sleep apnea headaches appear to be related to disturbances in nocturnal sleep. Dysregulation in regions that modulate sleep and nociception may be one possible mechanism.

The Five Times Sit to Stand Test as a Tool to Assess Disability and Physical Capacity after Hospitalization for COVID-19

Background: Assessment of exercise tolerance should be an integral part of the follow- up of COVID-19 survivors. Objective: We aimed in this study to investigate the correlation between the 5 Times Sit to Stand Test (5STST) and the 6-Minute Walk Test (6MWT) and to determine their place in assessing exercise tolerance and disability in COVID-19 survivors. Methods: This was a cross-sectional study that included 201 survivors of COVID-19. All patients underwent a detailed medical questionnaire, assessment of disability by the Lawton scale, and sub- -maximal exercise tolerance by 6MWT and 5STST. Our study population was divided into two groups based on the Length of Hospital Stay (LHS) (&lt;10 or ≥10 days). Results: Compared with the group with a LHS &lt; 10 days, the group with prolonged LHS (≥10 days) had a significantly greater mean value of 5STST. In contrast, the mean values of 6-minute Walk Distance (6MWD) and Minimal Oxygen Saturation (MOS) were significantly lower. A significant correlation of 5STST with Lawton score (r = -0.373; p &lt; 0.0001) and 6MWD (r = -0.563; p &lt; 0.0001) was also found. Conclusion: Our results showed that the 5STST was correlated with the 6MWD and Lawton score. Hence, it could be proposed to assess physical capacity and disability, especially in patients who had a prolonged LHS for COVID-19.

Biodegradable packaging paper derived from chitosan-based composite barrier coating for agricultural products preservation

Development of green packaging materials is essential to replace traditional plastics in fresh agricultural products preservation. Herein, a coated paper was designed by applying chitosan-based composite coating on paper substrate through a facile automatic coating method. The hydroxypropyl trimethyl ammonium chloride chitosan (HACC) was obtained by direct quaternization via the introduction of hydroxypropyl trimethyl ammonium chloride into the amino group of chitosan, then mixed with polyvinyl alcohol (PVA) to prepare the HACC/PVA coating. Accordingly, the key performance of coated paper were improved ascribed to the synergy effect of HACC/PVA coating and paper substrate. In particular, the minimum oxygen permeability of the coated paper could reach to 0.87 × 10−13 cm3·cm/cm2·s·Pa, and the optimum water vapor permeability and tensile strength of HACC/PVA coated paper was 0.75 × 10−12 g·cm/cm2·s·Pa and 6.88 kN/m, respectively. The coated paper used as packaging material not only reduced weight loss ratio of strawberry and greengrocery, but also exhibited lower chromatic aberration and better sensory evaluation, indicating a favorable effect on fruit and vegetable storage. Taken together, the designed eco-friendly coated paper has shown tremendous potential for green and biodegradable packaging material in agricultural products preservation.

Combining the probabilistic finite element model and artificial neural network to study nutrient levels in the human intervertebral discs

BackgroundDiffusion distance and diffusivity are known to affect nutrient transport rates, but the probabilistic analysis of these two factors remains vacant. There is a lack of effective tools to evaluate disc nutrient levels. MethodsFive-hundred-disc samples with different combinations of morphological and water content parameters were generated, which were used to evaluate nutrient levels in unloaded and loaded states. Spearman correlation coefficients between inputs and responses were calculated. Artificial neural networks were trained to predict nutrient concentrations based on the dataset generated by the probabilistic finite element model. FindingsIn unloaded and loaded states, the minimum oxygen concentration of nucleus pulposus was negatively correlated with disc height (r = −0.83, p < 0.01 and r = −0.76, p < 0.01, respectively), and the minimum glucose concentration of annulus fibrosus was positively correlated with its water content (r = 0.68, p < 0.01 and r = 0.73, p < 0.01, respectively). The maximum lactate concentration of cartilage endplate was affected by endplate thickness (r = 0.94, p < 0.01 and r = 0.95, p < 0.01, respectively). For trained neural networks, nutrient concentrations could be well predicted, with coefficients of determination greater than 0.95 and mean absolute percentage errors less than 5 %. InterpretationThis study underscores the importance of disc height, annulus fibrosus water content, and endplate thickness in regulating nutrient levels, and precise control of these parameters should be prioritized in the design of tissue-engineered discs. Moreover, artificial neural networks might be a promising tool for evaluating nutrient levels.

Exploratory Study of Relationship Between Obstructive Sleep Apnea Syndrome and Growth Hormones and Inflammatory Factors in Children

Purpose: In children, obstructive sleep apnea (OSA) is associated with growth hormone level abnormalities and chronic systemic inflammation. This study was performed to investigate the relationship of the degree of OSA with insulin-like growth factor 1 (IGF-1) and inflammatory cytokines in pediatric OSA and the inter-relationship between inflammatory cytokines and growth hormones. Methods: Children with OSA and controls without OSA participated in the study. Information included polysomnography followed by measurement of IGF-1 and inflammatory marker levels. In total, 226 patients aged 2 to 12 years were divided into 4 groups: non-OSA, n = 57 (25.2%); mild OSA, n = 116 (51.3%); moderate OSA, n = 23 (10.2%); and severe OSA, n = 30 (13.3%). Results: Body height was not significantly different among the 4 groups. However, the minimum oxygen saturation and IGF-1 significantly differed among the different OSA groups ( P = .0001 and P = .036, respectively). IGF-1 was significantly higher in the non-OSA group ( P &lt; .05) and mild OSA group ( P &lt; .01) than in the severe OSA group. As the severity of OSA increased, the interleukin-5 level significantly increased, which caused a difference between mild OSA and moderate OSA ( P &lt; .05) and between mild OSA and severe OSA ( P &lt; .001). In the univariate quantile regression analysis of IGF-1, there was a negative relationship between IGF-1 and IL-5 ( P &lt; .001). IGF-1 was positively correlated with age, height, and minimum oxygen saturation. Furthermore, there was a negative correlation between the IGF-1 level and the severity of OSA. Quantile regression analysis on the multivariable analysis of the IGF-1 association showed that height, sex, and severity of OSA played important roles in affecting IGF-1 levels. Conclusion: High IL-5 levels may lead to the low secretion of growth hormone level (IGF-1) in children, thus affecting growth and development.

Comprehensive study on mechanical and ignition properties of newly synthesized lanthanide complexes for flame retardant paint additives

This study presents the synthesis and characterization of novel lanthanide complexes, specifically La (III) and Gd (III), designed as flame-retardant additives for paint formulations. The complexes were synthesized and thoroughly characterized using different spectroscopic techniques, complemented by density functional theory computational calculation insights. The resulting La (III) and Gd (III) complexes were then incorporated into paint formulations, and the physical properties of the modified coatings were systematically evaluated. Ignitability and the minimum oxygen percentage required for sustained combustion were quantified according to standardized procedures. The modified coatings demonstrated enhanced mechanical and ignition properties in comparison to blank samples. The limiting oxygen index (LOI) values were notably higher, underscoring the efficacy of the lanthanide complexes as flame retardant additives. La complex led to an ignition time of 850 s and an LOI of 40, while Gd complex resulted in the same ignition time of 850 s and LOI of 50 compared to the uncoated sample of 550 s and an LOI of 16. The mechanical properties of the painted samples, engineered with the inclusion of these prepared metal complexes, exhibited a significant improvement. This comprehensive investigation provides valuable insights into the potential application of lanthanide complexes as effective flame-retardant additives in coatings, offering a promising avenue for enhancing the safety and performance of various materials.

Portable polygraphic device (Somnocheck micro CARDIO®) provides accurate diagnostic information in psychiatric patients at risk for obstructive sleep apnoea: an observational cohort study

BackgroundSymptoms of obstructive sleep apnoea (OSA) overlap significantly with those of psychiatric disorders, making accurate diagnosis of OSA challenging within psychiatric settings. Diagnosing OSA in psychiatric patients is crucial because untreated OSA can exacerbate psychiatric symptoms, reduce treatment efficacy, and impair overall quality of life. This study aimed to determine the diagnostic accuracy of a readily accessible procedure for psychiatric patients in a real-world clinical setting by comparing the Somnocheck micro CARDIO® (SCm) portable cardiorespiratory polygraphy device with the gold standard polysomnography (PSG).MethodsThis observational cohort study included consecutive psychiatric patients at intermediate to high risk for OSA based on screening with the STOP-Bang questionnaire, admitted to a single tertiary care centre between June 1, 2016 and December 31, 2022. The Apnoea-Hypopnoea-Index (AHI), Apnoea-Index (AI), Oxygen-Desaturation-Index (ODI), and minimum oxygen saturation were measured sequentially by SCm and PSG.ResultsA total of 57 patients were analysed (median age 62.0 [Interquartile Range (IQR), 51.5–72.5] years; 34 [59.6%] men). Regarding AHI, no significant differences (AHI measured by PSG, median, 16.6 [IQR, 6.2–26.7] vs. AHI measured by SCm, median, 14.9 [IQR, 10.0-22.8]; p = 0.812; r = 0.71) were found between SCm and PSG. AI, ODI and minimum oxygen saturation differed significantly between SCm and PSG. Using optimised cut-off values (any OSA: AHISCm ≥ 9.25), SCm showed high sensitivity (0.894) and high specificity (0.800) for the diagnosis of OSA, with an area under the receiver operating characteristic curve of 0.877.ConclusionsThis study found that the SCm portable device was accurate in identifying psychiatric patients with OSA. AHI measurement by SCm provided reliable diagnostic performance in comparison with the gold standard polysomnography. These findings support the integration of polygraphic measurements into the routine sleep assessment of psychiatric patients. Early and accurate diagnosis of OSA in this population can significantly improve the management of both sleep disorders and psychiatric conditions, potentially enhancing overall treatment outcomes and quality of life for these patients.

Winkler Titration Assessment of Biochemical Oxygen Demand (BOD5) in Oka Creek, Toru-Orua, Bayelsa State

Aim: The aim of study was to investigate the Biochemical Oxygen Demand (BOD) levels in water samples from the Oka Creek. Study Design: Qualitative study design. Place and Duration of Study: Water samples were collected from the Oka Creek, located in Toru-Orua in Sagbama Local Government Area, Bayelsa State, Nigeria. The study lasted for twenty days. Methods: Water samples were collected from four different locations and depths in the Oka Creek, Toru-Orua, Sagbama Local Government Area of Bayelsa State, Nigeria, at various times. Each sample was transferred into 250 ml bottles labeled L1, L2, L3, and L4. The temperatures of the samples were recorded before transporting them to the chemistry laboratory for treatment. Winkler titration method was employed in analyzing the samples. Results: Location L1 recorded the highest BOD value, 28.38 ppm, measured at sunset (25 °C), from a relatively stagnant region. The high BOD at this location is attributed to minimal photosynthetic activity and significant oxygen consumption by microorganisms. In contrast, L2, collected from the same region at 35 °C during peak sunlight, exhibited a BOD value of 21.76 ppm. The lower BOD at L2 is due to increased photosynthetic activity. These high values suggest significant sludge deposits, domestic sewage and agricultural runoffs, which could lead to oxygen depletion and negatively impact aquatic life. Sample L3, taken from a deeper, stagnant region at sunset (25 °C), recorded a BOD value of 4.50 ppm. This moderate BOD level suggests the presence of moderate sludge deposits and agricultural runoff, but higher water flow speed helped mitigate these effects. Location L4, with the lowest BOD value of 3.74 ppm, was collected during peak sunlight (35 °C). Deeper location and high water flow speed contributed to reduced BOD levels, indicating better water quality and a healthier aquatic environment. Conclusion: The BOD values at L1 and L2 (28.38 ppm and 21.76 ppm) exceed acceptable limits for fish growth. Conversely, BOD values at L3 and L4 (4.50 ppm and 3.74 ppm) fall within acceptable limits, suggesting healthier aquatic environment, as evidenced by the yearly bountiful fish harvests in these sections of the Oka Creek.

Investigation on the microstructure and high-temperature properties of AlN coating through oxygen addition

This study meticulously examines how oxygen incorporation alters the microstructure, mechanical, and high-temperature properties of AlN coating prepared via cathodic arc deposition. Substitution of nitrogen by oxygen in the AlN lattice leads to the formation of Al(OxN1-x)y metastable solid solutions from wurtzite Al(O)N structure to cubic AlO(N) structure, culminating in a full conversion to γ-Al2O3 with increased oxygen content. This substitutive solid solution induces solid solution strengthening and grain refinement effect, thereby escalating hardness from ∼18.5 GPa for AlN to ∼23.9 GPa for Al(O0.18N0.82)1.09. Despite an observed tendency towards enhanced thermal decomposition of oxynitride coatings upon annealing, the occurrence of α-Al2O3 oxide phase significantly preserves the mechanical integrity at elevated temperatures, outperforming pure AlN coating. Notably, the strategic alteration by minimal oxygen incorporation facilitates the formation of an Al-rich oxide layer, which exhibits superior anti-oxidative characteristics. After oxidation at 1100 °C for 10 h, the Al(O0.10N0.90)1.03 with an oxide layer of ∼1.2 μm exhibits remarkable oxidation resistance.

Enhancing the Efficiency and Stability of Perovskite Solar Cells Using Chemical Bath Deposition of SnO2 Electron Transport Layers and 3D/2D Heterojunctions.

Chemical bath deposition (CBD) is an effective technique used to produce high-quality SnO2 electron transport layers (ETLs) employed in perovskite solar cells (PSCs). By optimizing the CBD process, high-quality SnO2 films are obtained with minimal oxygen vacancies and close energy level alignment with the perovskite layer. In addition, the 3D perovskite layers are passivated with n-butylammonium iodide (BAI), iso-pentylammonium iodide (PNAI), or 2-methoxyethylammonium iodide (MOAI) to form 3D/2D heterojunctions, resulting in defect passivation, suppressing ion migration and improving charge carrier extraction. As a result of these heterojunctions, the power conversion efficiency (PCE) of the PSCs increased from 21.39% for the reference device to 23.70% for the device containing the MOAI-passivated film. The 2D perovskite layer also provides a hydrophobic barrier, thus enhancing stability to humidity. Notably, the PNAI-based device exhibited remarkable stability, retaining approximately 95% of its initial efficiency after undergoing 1000-h testing in an N2 environment at room temperature.