Gas Parameters Research Articles

Ginsenoside Rg1 Prevents and Treats Acute Pulmonary Injury Induced by High-Altitude Hypoxia

This study aimed to investigate the protective effects of ginsenoside Rg1 on high-altitude hypoxia-induced acute lung injury (ALI) and elucidated its molecular targets and related pathways, specifically its association with the fluid shear stress pathway. Using a combination of bioinformatics analysis and both in vivo and in vitro experiments, we assessed the role of ginsenoside Rg1 in mitigating physiological and biochemical disturbances induced by hypoxia. In the in vivo experiments, we measured arterial blood gas parameters, levels of inflammatory cells and cytokines, erythrocyte and platelet parameters, and conducted histological analysis in rats. The in vitro experiments utilized human pulmonary microvascular endothelial cells (HPMECs) and A549 cells to examine cell viability, intracellular reactive oxygen species (ROS) and Ca2⁺ levels, and mitochondrial function. The results of the in vivo experiments demonstrate that ginsenoside Rg1 significantly increased arterial blood oxygen partial pressure and saturation, elevated arterial blood glucose levels, and stabilized respiratory and metabolic functions in rats. It also reduced inflammatory cells and cytokines, such as tumor necrosis factor-α and interleukin-6, and improved erythrocyte and platelet abnormalities, supporting its protective role through the regulation of the fluid shear stress pathway. Histological and ultrastructural analyses revealed that Rg1 significantly protected lung tissue structure and organelles. In vitro experiments further confirmed that Rg1 improved cell viability in HPMEC and A549 cells under hypoxic conditions, decreased intracellular ROS and Ca2⁺ levels, and enhanced mitochondrial function. These findings collectively demonstrate that ginsenoside Rg1 exerts significant protective effects against high-altitude hypoxia-induced ALI by enhancing oxygen delivery and utilization, reducing inflammatory responses, and maintaining cellular metabolism and vascular function. Notably, the protective effects of Rg1 are closely associated with the regulation of the fluid shear stress pathway, suggesting its potential for treating high-altitude hypoxia-related diseases.

The Relationship between the Improvement Level in Blood Gas Parameters in Time and Brain MRI Findings in Newborns with the Diagnosis of Hypoxic Ischemic Encephalopathy

The Relationship between the Improvement Level in Blood Gas Parameters in Time and Brain MRI Findings in Newborns with the Diagnosis of Hypoxic Ischemic Encephalopathy

Paradoxical hypoxemia following positive pressure ventilation: exploring the pathophysiology

Positive pressure ventilation (PPV), both non-invasive and invasive, enhances ventilation but can sometimes lead to unexpected hypoxemia. This case report describes an instance of paradoxical hypoxemia after initiating bilevel positive airway pressure (BiPAP) in a 58-year-old female with a medical history of systemic lupus erythematosus, interstitial lung disease, and pulmonary embolism. BiPAP was started, leading to improved hypercarbia but worsened hypoxemia. Further investigation revealed a right-to-left interatrial shunt via a small patent foramen ovale (PFO). Adjusting BiPAP settings improved arterial blood gas parameters. This case illustrates how positive pressure ventilation with underlying PFO can cause paradoxical hypoxemia. The case emphasizes the importance of understanding the pathophysiology and tailoring BiPAP settings based on individual haemodynamics.

Simultaneous detection of soot, temperature, and C2H2 in laminar premixed flames using a multi-pass diode laser absorption spectrometer

We report the development of a multi-pass diode laser absorption spectroscopy system for simultaneous measurements of soot volume fraction (SVF), temperature, and C2H2 concentration using a single diode laser near 1.543 µm. A line-shaped beam spot pattern is chosen for the open-path Herriott multi-pass cavity, enabling sensitive detection at various heights above the burner with an effective optical absorption path length of approximately 1.2 m in a 6 cm diameter flame region. The gas parameters (temperature and C2H2 concentration) and the SVF are determined from the absorption spectra of the target C2H2 line pair and the laser extinction of the soot, which can be extracted from the detected signal, respectively. The performance of the system was confirmed in laminar premixed ethylene and air (C2H4/air) sooting flames produced by a standard bronze plug McKenna burner at four representative equivalence ratios. All the measurement results were compared with the two-dimensional (2D) computational fluid dynamics (CFD) simulations using a skeletal mechanism with the Moss−Brookes model. The good quantitative and qualitative agreement between the TDLAS measurements and 2D CFD simulations confirms the powerful capability of the developed system.

Clinical evaluation of serum miR-513a-3p combined with arterial blood gas analysis parameters and lung ultrasound score in neonatal respiratory distress syndrome

BackgroundNeonatal respiratory distress syndrome (NRDS) is harmful to neonates and the prognosis is variable, ranging from mild to severe forms. This study aims to evaluate the clinical utility of miR-513a-3p in conjunction with arterial blood gas analysis parameters and lung ultrasound (LUS) score in the context of NRDS.MethodsThe study included 169 preterm infants, including 106 newborns with NRDS and 63 newborns without NRDS. The relative expression level of miR-513a-3p was detected by quantitative real time polymerase chain reaction (qRT-PCR). Umbilical artery blood gas parameter values and LUS score were recorded, and the clinical significance of miR-513a-3p, umbilical artery blood gas parameter and LUS score in NRDS were evaluated by Receiver Operating Characteristic (ROC) analysis.ResultsElevated levels of miR-513a-3p were detected in the serum of NRDS, and higher expression of miR-513a-3p was observed in individuals with poor prognosis. Notably, miR-513a-3p exhibited a significant correlation with the parameters of arterial blood gas analysis and LUS score in NRDS patients. Furthermore, miR-513a-3p was one of the risk factors for poor prognosis in NRDS patients. miR-513a-3p levels combined with umbilical artery blood gas parameters and LUS score has diagnostic value for NRDS and is reliable for its prognosis.ConclusionsElevated levels of miR-513a-3p in neonatal serum served as a useful tool in the combined assessment with umbilical artery blood gas analysis and LUS score to diagnosis and prognosis of NRDS. Consequently, miR-513a-3p may be served as a biomarker for diagnosis and prognosis of NRDS.

Intramuscular injection of a commercially available medetomidine-vatinoxan hydrochloride mixture produces reliable sedation in sheep and goats with varying cardiopulmonary effects.

To evaluate the sedation quality of an IM injection of a commercially available medetomidine-vatinoxan combination (ZEN) in healthy goats and sheep and discern species differences in cardiopulmonary parameters. 10 apparently healthy adult university-owned research Black Bengal-crossbreed goats and 10 adult Gulf Coast native and Katahdin sheep were enrolled in this prospective experimental study from June 27 to July 27, 2023. All animals were sedated on 1 occasion with 0.06 mL of ZEN/kg, IM (0.03 mg of medetomidine/kg and 0.6 mg of vatinoxan hydrochloride/kg). Cardiopulmonary variables including heart rate, arterial blood pressure, and arterial blood gas parameters were recorded along with sedation depth and duration. Any animals still sedated after 150 minutes received 0.01 mg of atipamezole/kg. The mean ± SD of the total sedation time for sheep and goats was 102.80 ± 10.90 minutes and 133.50 ± 32.63 minutes, respectively. Profound reliable sedation was achieved in all but 1 animal. Hypoxemia was observed in sheep and goats (11 of 20 animals total). Hypotension was seen in 3 of 10 goats. In sheep and goats, ZEN at 0.06 mL/kg, IM, caused profound sedation. Total sedation time was significantly longer in goats than in sheep. In the presence of oxygen supplementation, ZEN at 0.06 mL/kg, IM, may be an acceptable sedation choice for apparently healthy Gulf Coast native and Katahdin sheep, but not goats; however, preexisting hypokalemia or pulmonary disease are contraindications for the use of ZEN in sheep.

Predicting the Physical Properties of Dark Matter Subhalos from Baryonic Parameters Using Machine Learning

Dark matter subhalos play an important role in galaxy formation and evolution. However, accurate prediction of dark matter properties remains a challenge of modern-day astronomy. In recent times, machine learning (ML) tools have shown promising results in solving numerous astrophysical problems. In this paper, we use data from the EAGLE simulations to determine the total mass and the half-mass radius of dark matter subhalos using structural properties of gas, star, black hole, and photometric features using gradient boosted decision trees (GBDT) and dense neural network. GBDT does not require data preprocessing, and results in better performance compared to the neural network. According to GBDT, the most important feature for subhalo radius and mass estimation is gas radius and black hole mass respectively. The all-features combined approach results in the highest test accuracy — Pearson’s correlation coefficient = 0.947 and 0.981, coefficient of determination = 0.898 and 0.962, normalized median absolute deviation = 0.111 and 0.114 for radius and mass respectively. We evaluate our model for masses and redshifts beyond its training range and find that GBDT demonstrates significantly better extrapolation capabilities than the neural network. We also test our model on simulations with different resolutions, and find that the discrepancies lie within 10% if the resolution is changed. This novel study incorporates the structural parameters of gas and black hole to determine the dark matter properties using a ML-based approach. The promising results of this study prove that ML tools can improve our current understanding of dark matter, and answer some of the basic cosmological questions.

Predicting outcomes in patients with exacerbation of COPD requiring mechanical ventilation

BackgroundAcute exacerbations of COPD (AECOPD) are common and significantly contribute to mortality in patients with COPD. Prognostic scores can assist clinicians in making tailored decisions to manage AECOPD. In the current study, we therefore aimed to evaluate the performance of the Noninvasive Ventilation Outcomes (NIVO) score, originally designed to assess in-ICU mortality, in predicting 1 year mortality and NIV failure in AECOPD.MethodsThis retrospective study analyzed data from patients hospitalized for AECOPD requiring mechanical ventilation between January 1st, 2018, and December 31st, 2022. Mortality was assessed at the end of ICU stay and 1 year after admission, while NIV failure was defined as intubation or death without intubation.ResultsAmong 302 ICU admissions of COPD patients, 190 patients with AECOPD requiring mechanical ventilation were included. Of these, 44 (23%) died in the ICU, 62 out of 184 (34%) failed NIV, and 78 (41%) died within 1 year of admission. Patients who died in ICU or experienced NIV failure had more severe COPD and more impaired blood gas parameters at admission. The NIVO score demonstrated an AUC of 0.68 in predicting 1-year mortality and an AUC of 0.85 in predicting NIV failure. A NIVO score over 7 was associated with higher 1-year mortality and NIV failure (HR of 4.4 [1.8–10.9] and 41.6 [5.6–307.9], respectively).ConclusionBeyond predicting in-ICU mortality, the NIVO-score is a reliable tool in predicting 1-year mortality and NIV failure in AECOPD.

Experimental Analysis of Shale Cuttings Migration in Horizontal Wells

The extraction of shale gas via horizontal drilling presents considerable challenges, primarily due to the accumulation of cuttings within the annular space, resulting in increased friction, torque, and potential drilling complications. To address this issue, the study proposes an experimental setup aimed at simulating cuttings transport under various operational conditions, with a particular emphasis on gas wells. The methodology encompasses the modulation of the drilling fluid flow rate and the drill’s rotational speed to examine the transport velocity of cuttings. Furthermore, the study analyzes the impact of annular eccentricity on return volume, transport time, and cuttings bed height. Critical initiation velocities for cuttings across different motion modes were also determined, and theoretical calculations were compared with empirical data. The findings indicate that an increased flow rate of drilling fluid and higher rotation speed substantially improve the transport of cuttings, thereby minimizing bed formation, whereas increased eccentricity hinders this process. The results revealed that the theoretical model showed a greater overestimation of the start-up velocity for spherical particles, with average errors ranging from 15.50% to 17.56%. In contrast, the model exhibited better accuracy for non-spherical (flaky) particles, with errors between 8.63% and 9.61%. Under non-rotating conditions, the average error of the model was approximately 8.32%, while the introduction of drill tool rotation increased the average error to 11.94%. These results have the potential to optimize operational parameters in shale gas well drilling and may contribute to the development of specialized borehole purification tools.

Study on radiation characteristics of multi-phase plumes containing ice crystals in orbit-control engines

In order to obtain the radiation characteristics of the multiphase plume containing ice crystals in the high-altitude orbit control engine and analyze its influence on the telemetry effect, this paper deduces the radiation characteristics parameters of gases based on Einstein radiation theory and radiation transfer equation. Based on the latest HITRAN2020 spectral line library solving gas radiation and the Mie theory of particle scattering solving particle radiation, the radiation characteristic parameters of the multi-phase plume containing ice crystals in the high-altitude orbital control engine and the radiation intensity distribution in the near-infrared and mid-long wave infrared bands are simulated, and the main influencing factors of the radiation are analyzed. The results show that, in general, the main radiation of the engine plume includes the scattered light in the near infrared band and the thermal radiation in the middle long wave infrared band. In the near-infrared band, considering solar background radiation, the total radiation amount in the calculation domain is about 10 −6 W/sr, and the thermal radiation is dominant within the axial distance of 0.5 m, while the ice crystal scattering is dominant beyond the axial distance of 0.5 m . In the mid-long wave infrared band, the total radiation amount in the calculation domain is about 10 W/sr, and the thermal radiation of gas dominates within 1 m axial distance, while the thermal radiation of ice crystal dominates beyond 1 m axial distance.

Methylene Blue and Blood Transfusion in Hemorrhagic Shock Resuscitation: An Experimental Porcine Study.

Hemorrhagic shock requires immediate treatment to prevent mortality and organ dysfunction. This study evaluates the efficacy of methylene blue (MB) with blood transfusion (BT) as a potential rescue therapy in acute severe bleeding in pigs. Thirty animals were randomly assigned to one of six groups following the induction of fixed-pressure hemorrhagic shock, after reaching a mean arterial pressure (MAP) of 55 mmHg - Group 1 (60 BT: BT after 60 minutes), Group 2 (60 MB: MB infusion after 60 minutes), Group 3 (60 MB + BT: MB and BT after 60 minutes), Group 4 (15 MB + BT: MB and BT after 15 minutes), Group 5 (15 BT + 60 MB: BT after 15 minutes and MB infusion after 60 minutes), and Group 6 (15 MB + 60 BT: MB infusion after 15 minutes and BT after 60 minutes). Hemodynamic and blood gas parameters were meticulously recorded, reversal of the shock was considered when MAP reached 90% of the baseline MAP. Except for Group 2, all groups reverted from the shock. However, groups that received MB in combination with BT, specifically Groups 3 and 4, exhibited statistically significant higher ratios of maximum MAP to baseline MAP. Using MB concomitant with BT allowed the reversal of hemorrhagic shock with higher median arterial pressure levels compared to BT alone or applying MB separately from BT. This suggests that simultaneous application of MB and BT could be a more effective strategy for reversing the effects of severe acute bleeding.

Error analysis and improvement of water displacement method in measuring gas desorption volume from coal particles

The water displacement method is widely employed in experiments to investigate the adsorption and desorption characteristics of coal gas. However, conventional desorption apparatus faces challenges in accurately quantifying gases with low desorption rates, leading to significant inaccuracies in experimental assessments of residual gas content and adsorption–desorption hysteresis. In order to solve the issue, a new desorption device was invented to carry out isothermal ultimate desorption experiments together with the conventional device under two different equilibrium pressures with coal samples of four particle sizes. The results reveal that after 100 min, the gas desorption rate gradually decreases, with the desorption percentage of the conventional device remaining relatively constant, while that of the new device continues to rise. By the end of the experiment, the conventional device measured gas residual percentages ranging from 30 % to 50 %, whereas the new device recorded percentages between 10 % and 25 %. The lower residual percentages obtained by the new device prove the effectiveness to solve the issue that the conventional devices struggle to quantify low-rate desorption gas.When applying the conventional device, as desorption progresses, the desorption rate decreases, and the pressure within the coal sample tank increases more slowly, which results in the difficulty for the gas to reach a pressure of 71.18 Pa to overcome fluidic constraints and enter into the graduated cylinder and ultimately accumulates in the soft, large-volume silicone pipeline. In contrast, the new device, designed with its gas outlet strategically positioned above the liquid level, bypasses the constraints of liquid forces. Additionally, the modest inner diameter of the rigid tube undergoes minimal deformation under experimental conditions. Differences in liquid forces and piping allow the new device to accumulate 71 mL less gas than the conventional device. The utilization of the new device in coal gas desorption experiments effectively mitigates experimental errors stemming from low desorption rates, thereby driving advancements in the investigation of coal seam gas parameters and residual gas content.

Integrating Flow Field Dynamics and Chemical Atmosphere Predictions for Enhanced Sulfur Corrosion Risk Assessment in Power Boilers.

In this work, we attempt to explain the phenomenon of sulfur corrosion of power boiler water walls under the conditions of large fluctuations in carbon monoxide concentrations. To assess the conditions required for corrosion formation, a criterion based on the chemical and flow field parameters of the flue gas is proposed. The formulated sulfur corrosion criterion is based on the mixture fraction variance and the turbulence time scale. Numerical modeling of coal combustion in a 250 MW power boiler is performed using ANSYS. Two cases of combustion in a boiler are analyzed, with the first simulating the boiler operated using classic high-swirl burners and the second one accounting for boiler operation with modified low-swirl burners. Calculations of pulverized coal combustion are performed using the standard k-ε turbulence model and the combustion described by the mixture fraction. The simulation results reveal that the low-swirl burner is characterized by higher values of the mixture fraction variance and a higher frequency of fluctuation of the velocity field, which is strongly related to an increased corrosion rate. The study outcomes show the validity of using the criterion of the mixture fraction variance and velocity field fluctuations to determine the areas at risk of sulfur corrosion.

Comparative Study of Temperature and Pressure Variation Patterns in Hydrogen and Natural Gas Storage in Salt Cavern

Clarifying the distribution of temperature and pressure in the wellbore and cavern during hydrogen injection and extraction is crucial for quantitatively assessing cavern stability and wellbore integrity. This paper establishes an integrated flow and heat transfer model for the cavern and wellbore during hydrogen injection and withdrawal, analyzing the variations in temperature and pressure in both the wellbore and the cavern. The temperature and pressure parameters of hydrogen and natural gas within the chamber and wellbore were compared. The specific conclusions are as follows. (1) Under identical injection and withdrawal conditions, the temperature of hydrogen in the chamber was 10 °C higher than that of natural gas, and 16 °C higher in the wellbore. The pressure of hydrogen in the chamber was 2.9 MPa greater than that of natural gas, and 2.6 MPa higher in the wellbore. (2) A comparative analysis was conducted on the impact of surrounding rock’s horizontal and numerical distance on temperature during hydrogen and natural gas injection processes. As the distance from the cavity increases, from 5 to 15 m, the temperature fluctuation in the surrounding rock diminishes progressively, with the temperature effect in the hydrogen storage chamber extending to at least 10 m. (3) The influence of rock thermal conductivity parameters on temperature during the processes of hydrogen injection and natural gas extraction is also compared. The better the thermal conductivity, the deeper the thermal effects penetrate the rock layers, with the specific heat capacity having the most significant impact.

Effect of Chlordiazepoxide or Haloperidol Oral Premedication during Midazolam-Ketamine Anaesthesia on Physiological and Blood Gas Parameters in Adult Male Bonnet Macaques (Macaca radiata)

Capturing wild animals with minimal stress is crucial to reduce morbidity and mortality. Oral premedicants can ease handling and subsequent anaesthetic administration. This study evaluated anaesthetic protocols and physiological changes during vasectomy in 12 adult male Bonnet Macaques. Group I received 10 mg/kg chlordiazepoxide, and Group II received 1 mg/kg haloperidol orally four hours before midazolam-ketamine anaesthesia. Sedation quality, induction, maintenance, and recovery were assessed. Physiological and blood gas changes were monitored at 0, 5, 10, 15, and 20 minutes. Both groups exhibited sedation post-premedication. Induction, maintenance, and anaesthesia depth were similar. Group I had better analgesia, while Group II had superior muscle relaxation. Blood gas analysis indicated mild stress and respiratory acidosis in both groups, with Group II showing more significant hypoxemia and respiratory acidosis. Haloperidol-premedicated animals were easier to handle but exhibited increased stress parameters compared to chlordiazepoxide-premedicated animals. Recovery was better in Group I. Both protocols effectively induced sedation and anaesthesia in Bonnet Macaques.

Monotropein alleviates acute pulmonary embolism in rats by inhibiting the NF-κB pathway

Objective This study examines the therapeutic potential of monotropein (Mon) in a rat model of acute pulmonary embolism (APE), aiming to elucidate its mechanistic role and provide new insights for APE treatment. Methods: Thirty Sprague Dawley (SD) rats were randomly assigned to five groups (n = 6 per group): sham, Mon (40 mg/kg), APE, APE + 20 mg/kg Mon, and APE + 40 mg/kg Mon. APE was induced via autologous thrombus infusion in all groups except sham and Mon-only groups. We assessed blood gas parameters, lung wet/dry weight (W/D) ratio, and oxidative stress markers. Additionally, excised lung tissues underwent evaluation for serum inflammatory factors via ELISA, apoptotic cells via TUNEL assay, and protein expression via Western blot. Results: Compared to the sham group, APE-induced rats exhibited significantly elevated blood oxygen levels and increased pro-inflammatory factors, including interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-8. Mon treatment effectively mitigated these APE-induced changes, reducing blood oxygen concentration and downregulating IL-1β and TNF-α levels. Furthermore, Mon demonstrated anti-apoptotic effects by decreasing cleaved caspase-3 and Bax protein levels while upregulating Bcl-2 expression. Mon also suppressed nuclear factor-κB (NF-κB) activation by inhibiting the phosphorylation levels of p65/RelA and IκBα proteins, while the total protein level of IκBα was increased with Mon treatment. Conclusion: Mon effectively ameliorated lung tissue injury in APE rats by inhibiting apoptosis, attenuating inflammatory responses, and alleviating oxidative stress. These beneficial effects appear to be mediated through modulation of the NF-κB pathway, suggesting Mon as a promising therapeutic candidate for APE treatment.

A high-flow nasal cannula versus noninvasive ventilation in acute exacerbations of chronic obstructive pulmonary disease

PurposeWe investigated the efficacy and safety of a high-flow nasal cannula (HFNC) at different flow rates compared to noninvasive ventilation (NIV) in patients with acute chronic obstructive pulmonary disease (COPD) exacerbations. MethodsThis prospective, randomized, single-blind study assigned patients to one of three study groups. The NIV group (n = 47) received bilevel positive airway pressure. The HFNC-30 (n = 44) and HFNC-50 (n = 46) groups received HFNC therapy at flow rates of 30 and 50 L/min, respectively. Demographic and clinical characteristics and arterial blood gas parameters before and 30, 60, and 120 min after treatment were compared among the treatment groups. ResultsThis study included 137 consecutive patients with acute exacerbations of COPD, comprising 90 males and 47 females, with a mean age of 68.1 ± 10.5 years. A total of 21 patients (15.33 %) were intubated, and the overall mortality rate was 10.2 %. The mean PaCO2 levels on admission were 64.69 ± 10.81, 61.51 ± 9.03, and 62.29 ± 9.87 in the NIV, HFNC-30, and HFNC-50 groups, respectively, with no significant differences observed (p = 0.372). A significant reduction in mean PaCO2 was observed in all treatment groups at 30, 60, and 120 min (p < 0.05 for all). However, the ΔPaCO2 at 60 min was significantly higher in the HFNC-30 group compared to the NIV group (p = 0.042). Additionally, neither intubation rates nor 28-day mortality differed among the treatment groups (p = 0.368 and p = 0.775, respectively). ConclusionHFNC was not inferior to NIV in improving arterial blood gas parameters, particularly PaCO2 in patients with COPD exacerbations, especially those with hypercarbia. Moreover, HFNC at a flow rate of 30 L/min was superior to NIV for reducing PaCO2 levels at 60 min. Trial RegistryNational Library of Medicine Clinical Trial Registry; No.: NCT06495086; URL: https://clinicaltrials.gov/study/NCT06495086

DFT insights on the adsorption and sensing performance of TMO-MoSSe for oil dissolved gases

The safe operation of oil-immersed transformers is crucial to the overall stability of the power system, making the prevention of partial discharges vitally important. This study proposes the use of MoSSe doped with TMOs (CuO, Ag2O, TiO2) to detect dissolved gases (CO, C2H2, CH4) in transformer oil. The adsorption of target gases on pristine and modified substrates is systematically studied using density functional theory (DFT). Given the unique sandwich structure of MoSSe, this paper explores the stability of the S-plane and Se-plane doping, ultimately selecting the S-plane for doping. Compared with the initial band gap of the substrate (1.598 eV), doping with CuO, Ag2O, and TiO2 reduces the band gap of MoSSe to 1.535, 0.677, and 0.752 eV, respectively. In terms of sensing performance, the improvement provided by the oxide particles on the substrate is confirmed by analyzing the geometric structure, density of states (DOS), differential charge density (DCD), and work function (WF) of the adsorption system. By comparing the adsorption parameters of the target gas adsorbed on both the doped and initial substrates, it is found that the metal oxides enhance the adsorption of the target gas on MoSSe. CH4 exhibits weak physical adsorption on the three modified substrates, with the order of adsorption capacity being: C2H2 > CO > CH4. The results of this study provide a theoretical basis for future applications in transformer condition monitoring and gas sensing.

How does fetal inflammatory response syndrome change fetalresponse to hypoxia? An experimental study in a fetal sheep model.

Fetal inflammatory response syndrome associated with acidosis during labor is a high-risk situation for the fetus. This study evaluated hemodynamic, gasometric, and heart rate variability changes during acute fetal inflammatory response syndrome associated with hypoxia, compared with isolated hypoxia. Acute fetal inflammatory response syndrome was obtained via anintravenously injection of lipopolysaccharide derived from Escherichia coli. Hypoxia was induced by repeated umbilical cord occlusions during three phases: mild, moderate, and severe umbilical cord occlusions. Two groups were created with chronically instrumented near-term fetal sheep: one group with isolated hypoxia, the other with hypoxia and fetal inflammatory response syndrome. Hemodynamic, gas parameters, and fetal heart rate variability were compared between the groups. The hypoxia and fetal inflammatory response syndrome group had a higher mortality rate (n = 4/9) compared with the hypoxia group (n = 0/9). Gasometric state was altered earlier in case of lipopolysaccharide injection (pH = 7.22 (7.12-7.24) vs 7.28 (7.23-7.34) p = 0.01; lactate = 10.3 mmol/L (9.4-11.0) vs 6.0 mmol/L (4.1-8.2) p < 0.001 after mild occlusions). After mild occlusions, the hypoxia and fetal inflammatory response syndrome group had higher values on seven heart rate variability parameters compared with the hypoxia group. After moderate occlusions, two parameters remained significantly higher. During fetal inflammatory response syndrome, fetal adaptation to hypoxia is impaired. In case of fetal infection, acidosis during labor is likely to become severe more rapidly, requiring closer fetal monitoring during labor.

Reverse water-gas shift in a novel spark-coupled dielectric barrier discharge plasma: Effects of electrode structure and gas parameters

The reverse water–gas shift (RWGS) reaction holds promise for producing raw materials used in the synthesis of high-value chemicals. However, the reaction is often hindered by low CO2 conversion rates at atmospheric pressure and low temperatures. To overcome this limitation, this study developed a novel reactor based on strengthened spark-coupled dielectric barrier discharge (SSCDBD) without a catalyst, leveraging local high temperatures to enhance performance. The effects of reactor structure and gas parameters on conversion rate and energy efficiency were systematically investigated. The results indicated that the SSCDBD device notably improved CO2 conversion compared to conventional plasma techniques, such as dielectric barrier discharge (DBD), spark discharge, and spark-coupled dielectric barrier discharge (SCDBD), with respective increases of 1000 %, 12.65 %, and 2.79 %. Notably, varying the length of the auxiliary electrode affects the capacitance of the equivalent capacitor and, consequently, the discharge intensity. Furthermore, Increasing the electrode length from 4 cm to 20 cm improved the CO2 conversion rate from 43.7 % to 59.8 %. Moreover, CO2 conversion was positively correlated with the discharge distance, which also affected the volume of the electric arc. However, distances exceeding 1.2 cm interfered with arc formation. At a CO2:H2 molar ratio of 1:1, with an auxiliary electrode length of 12 cm and a discharge distance of 0.8 cm, the maximum CO2 conversion rate of 66 % was achieved at a total feed flow rate of 100 mL min−1, while maintaining a CO selectivity higher than 99 %. Additionally, with a total feed flow rate of 400 mL min−1, CO2 conversion reached 29 % and energy efficiency peaked at 6.34 %.