Partial Pressure Research Articles

Reaction kinetics and product evolution of hydrolysis in copper-chlorine thermochemical cycle for hydrogen production

By-products of the hydrolysis reaction in the copper-chlorine thermochemical cycle for hydrogen production are key to the final thermal and hydrogen efficiency. The current study focuses on the influences of reaction time, temperature, and steam partial pressure on the hydrolysis reaction and by-product formation mechanism via experimental and multiple analytical methods. The result demonstrates that the hydrolysis reaction of CuCl2 and steam converts to CuCl and Cu2OCl2, with a high conversion of 97%, while the Cu2OCl2 and CuCl2-CuO product mixtures exhibit interconversion capabilities. The increase of temperature increases the CuCl product content, while the decrease of steam partial pressure increases the by-product CuCl2. Particle morphology and reaction thermodynamics are analyzed for main and by-products formation. Finally, the homogeneous reaction model and shrinking core model are used and compared for the activation energy of the formation of Cu2OCl2 for the hydrolysis reaction and the effect of by-products.

Construction of Survival Nomogram for Ventilator-Associated Pneumonia Patients: Based on MIMIC Database.

Objective: To construct and validate a predictive nomogram model for the survival of patients with ventilator-associated pneumonia (VAP) to enhance prediction of 28-day survival rate in critically ill patients with VAP. Methods: A total of 1,438 intensive care unit (ICU) patients with VAP were screened through Medical Information Mart for Intensive Care (MIMIC)-IV. On the basis of multi-variable Cox regression analysis data, nomogram performance in predicting survival status of patients with VAP at ICU admission for 7, 14, and 28 days was evaluated using the C-index and area under the curve (AUC). Calibration and decision curve analysis curves were generated to assess clinical value and effectiveness of model, and risk stratification was performed for patients with VAP. Result: Through stepwise regression screening of uni-variable and multi-variable Cox regression models, independent prognostic factors for predicting nomogram were determined, including age, race, body temperature, Sequential Organ Failure Assessment score, anion gap, bicarbonate concentration, partial pressure of carbon dioxide, mean corpuscular hemoglobin, and liver disease. The model had C-index values of 0.748 and 0.628 in the train and test sets, respectively. The receiver operating characteristic curve showed that nomogram had better performance in predicting 28-day survival status in the train set (AUC = 0.74), whereas it decreased in the test set (AUC = 0.66). Calibration and decision curve analysis curve results suggested that nomogram had favorable predictive performance and clinical efficacy. Kaplan-Meier curves showed significant differences in survival between low, medium, and high-risk groups in the total set and training set (log-rank p < 0.05), further validating the effectiveness of the model. Conclusion: The VAP patient admission ICU 7, 14, and 28-day survival prediction nomogram was constructed, contributing to risk stratification and decision-making for such patients. The model is expected to play a positive role in supporting personalized treatment and management of VAP.

Preparation of nano Cu-Mo2C interface supported on ordered mesoporous biochar of ultrahigh surface area for reverse water gas shift reaction

High conversion rate and selectivity are challenges for CO2 utilization through catalytic reverse water gas shift (RWGS) reaction. Herein, a novel mesoporous biochar (MB) supported Cu-Mo2C nano-interface was prepared by consecutive physical activation of coconut shells followed by carbothermal hydrogen reduction of bimetal. As compared with traditional carbon materials, this MB exhibited ultra-high specific surface area (2693 m2 g–1) and mesopore volume of mesopore (0.81 cm3 g–1) with a narrow distribution (2–5 nm), responsible for the high dispersion of binary Cu-Mo2C sites, CO2 adsorption and mass transfer in the reaction system. Moderate carbothermal reduction led to the sufficient reduction of Mo ion with carbon matrix of MB and dispersive growth of nano Cu-Mo2C binary sites (~ 6.1 nm) on the surface of MB. Cu+ species were formed from Cu0 via electron transfer and showed high dispersion with simultaneous boosted bimetal loading due to the strong interaction between nano Mo2C and Cu. These were advantageous to the intrinsic activity and stability of the Cu-Mo2C binary sites and their accessibility to the reactant molecules. Under the RWGS reaction conditions of 500 °C, atmospheric pressure, and 300,000 ml/g/h gas hour space velocity, the CO2 conversion rate over Cu-Mo2C/MB reached 27.74 × 10–5 molCO2/gcat/s at very low H2 partial pressure, which was more than twice that over traditional carbon supported Cu-Mo2C catalysts. In addition, this catalyst exhibited 99.08% CO selectivity and high stability for more than 50 h without a decrease in activity and selectivity. This study offers a new development strategy and a promising candidate for industrial RWGS.Graphical

Optimization and Investigation of Hemoglobin‐Loaded ZIF‐90 Metal–Organic Framework Nanoparticles as Artificial Oxygen Carriers

AbstractBlood transfusions are vital, yet limited shelf‐life and storage conditions of red blood cells (RBCs) hinder their use in emergencies. Hemoglobin‐based oxygen carriers (HBOCs) aim to address these challenges, but previous versions faced clinical setbacks due to safety concerns related to hemoglobin (Hb) extravasation. ZIF‐90, a novel metal–organic framework variant where imidazole‐2‐carboxaldehyde (2‐ICA) is bridged to Zn2+ ions, is explored. Optimizing Zn2+:2‐ICA ratios and Hb concentrations, Hb‐loaded ZIF‐90 nanoparticles (NPs) are synthesized in one‐step and under mild synthesis conditions. These NPs achieve a 25.1% yield, 7.0 mg mL−1 Hb concentration, 70.3% encapsulation efficiency (EE), and 96.4% drug loading. They exhibit a left‐shifted oxygen dissociation curve with p50 of ≈8 mmHg, indicating enhanced oxygen release at lower partial oxygen pressures as compared to native RBCs. This feature makes Hb‐loaded ZIF‐90 NPs suitable for certain medical applications including ischemia‐reperfusion injury management. Furthermore, the impact of two prominent capping agents: polyvinylpyrrolidone and polyethylene glycol (PEG) is assessed. PEG improves 2‐ICA incorporation and stabilizes the ZIF‐90 crystalline phase, albeit with reduced yield, Hb content, and EE. The findings underscore the potential of Hb‐loaded ZIF‐90 NPs as next‐generation HBOCs, offering enhanced uniformity, high Hb content, and efficient oxygen binding and release properties for medical applications.

Assessment of the influence of glycol and alcohol on the morphology and protective properties of iron carbonate in carbon dioxide corrosion of gas pipelines

The potential effect of hydrate formation inhibitors (glycols, alcohols) — components of the liquid phase of gas pipeline operating media — on carbon dioxide corrosion during the transport of aggressive gas has not been sufficiently studied. The paper presents the results of a study of the corrosive effect of glycol (alcohol) present in the liquid phase on the composition and properties of corrosion products on steel when modeling the main aggressive factors under conditions of transport of CO2-containing gas. On a corrosion stand, the aggressive conditions of alternating wetting of gas pipeline walls with water were reproduced. The fluid circulation characteristic of a partially filled pipeline can have an effect on preventing the formation or destruction of films of corrosion products (iron carbonate, siderite) on the steel surface. In places of cracking and peeling of siderite formed in the presence of CO2, conditions will be created for the formation of general and local corrosion damage. During simulation tests, monoethylene glycol and isopropanol, as well as their aqueous solutions of different concentrations, were used. For the first time, data on the formation and composition of non-stoichiometric siderite in water-glycol and water-alcohol media at CO2 partial pressures and temperature were obtained. By processing diffraction patterns obtained by X-ray diffraction, the degree of substitution of iron ions in non-stoichiometric siderites by other cations was determined. The dependence of the degree of substitution on the concentration of alcohol (glycol) in their aqueous solutions was analyzed. It was revealed that with an increase in glycol concentration, a decrease in the rate of local corrosion is observed. With a high glycol content, internal corrosion is completely suppressed in the presence of CO2. It has been established that in aqueous-alcoholic media at elevated temperatures, local carbon dioxide corrosion does not occur. This is apparently due to the uneven distribution of water and alcohol in the mixture. The results obtained can be used in assessing internal carbon dioxide corrosion in the presence of glycol (alcohol), used at gas facilities as an inhibitor of hydrate formation.

Advancing the development of supersonic natural gas liquefaction through understanding heavy hydrocarbon crystallization mechanism

During supersonic natural gas liquefaction, the solidification of heavy hydrocarbon molecules can be used to improve the efficiency of the liquefaction. This study investigates the supersonic crystallization of n-hexane using an experimental system designed by ourself for precise measurement of liquid heavy hydrocarbon vaporization. The results demonstrate that n-hexane gas condenses rapidly 1.5 cm downstream of the nozzle throat, releasing significant latent heat. The subsequent crystallization of these droplets transitions the substance fully from liquid to solid, and the latent heat released during crystallization is much lower than that during condensation. Under different conditions, we found that higher partial pressures intensify n-hexane crystallization, accelerating liquid phase growth despite slower solid phase mass increase. Furthermore, larger nozzle expansion ratios shorten the time and space distribution of the liquid phase mass fraction. Molecular dynamics simulations reveal n-hexane’s melting and surface crystallization temperatures to be approximately 160 ± 1 K and 158 ± 1 K, respectively, with a supercooling degree of 2 K, explaining the observed crystallization behavior in supercooled droplets.

Resistance of Boron Nitride Nanotubes to Radiation-Induced Oxidation.

We present unprecedented results on the damage thresholds and pathways for boron nitride nanotubes (BNNT) under the influence of energetic electrons in an oxidative gas environment, using an environmental aberration-corrected electron microscope over a range of oxygen pressures. We observe a damage cascade process that resists damage until a higher electron dose, compared with carbon nanotubes, initiating at defect-free BNNT sidewalls and proceeding through the conversion from crystalline nanotubes to amorphous boron nitride (BN), resisting oxidation throughout. We compare with prior results on the oxidation of carbon nanotubes and present a model that attributes the onset of damage in both cases to a physisorbed oxygen layer that reduces the threshold for damage onset. Surprisingly, increased temperatures offer protection against damage, as do electron dose rates that significantly exceed the oxygen dose rates, and our model attributes both effects to a physisorbed oxygen population.

The Dissolution Behavior of Pyrite and Chalcopyrite During Low-Temperature Pressure Oxidation: Chalcopyrite Influence on Pyrite Oxidation

The research of this paper was carried out on the low-temperature (100 ± 2 °C) pressure (0.2–0.8 MPa) leaching of pyrite, chalcopyrite and their mixture. According to experiments on chalcopyrite dissolution, increasing the oxygen pressure from 0.2 up to 0.8 MPa had a slight effect on chalcopyrite dissolution. Oxygen pressure and initial sulfuric acid concentration in the range of 10–50 g/L had the greatest positive effect on the pyrite oxidation. The SEM and EDX mappings indicate the chalcopyrite and pyrite surfaces to be passivated by elemental sulfur. The oxidation degree of pyrite in its mixture with chalcopyrite increased significantly from 54.5 up to 80.3% in 0–240 min. The reaction time is relative to the dissolution of the individual mineral, while the dissolution of chalcopyrite remained virtually unchanged. The addition of Cu (II) and Fe (III) ions does not influence pyrite dissolution when chalcopyrite is added in a leaching process, which can be explained by the formation of an electrochemical link between the minerals. The positive effect of chalcopyrite addition is associated with a decreased formation of elemental sulfur on the surface of pyrite. The described method can be used for the hydrometallurgical processing of copper raw materials with increased pyrite content, as well as for the pretreatment of copper concentrates with gold-rich pyrite concentrates to increase the recovery of gold and silver.

Controllable and fast growth of high-quality atomically thin and atomically flat Bi2O2Se films

As a promising 2D material, bismuth oxyselenide (Bi2O2Se) has demonstrated significant potential to overcome existing technical barriers in various electronic device applications due to its unique physical properties like high symmetry, adjustable electronic structure, and ultra-high electron mobility. However, the rapid growth of Bi2O2Se films down to a few atomic layers with precise control remains a significant challenge. In this work, the growth of two-dimensional (2D) Bi2O2Se thin films by the pulsed laser deposition (PLD) method is systematically investigated. By controlling temperature, oxygen pressure, laser energy density, and laser emission frequency, we finally prepare atomically thin and flat Bi2O2Se (001) thin films on the (001) surface of SrTiO3. Importantly, we provide a fundamental and unique perspective toward understanding the growth process of atomically thin and flat Bi2O2Se films, and the growth process primarily proceeds in four steps. Moreover, the combined results of the crystallinity quality, surface morphology, and the chemical states demonstrate the PLD-growth of high-quality Bi2O2Se films in a controllable and fast mode.

Applicability of Waste from Al Industry toward Dephosphorization of Hot Metal in Primary Steel Making

Managing industrial waste is a global challenge. Red mud is a byproduct of the aluminum industry posing serious concerns. The presence of FeO and CaO in red mud makes it a potential DeP flux. Red mud has been utilized as a DeP flux in previous studies, but these studies deal with low Si content and no P2O5 content in the red mud. However, certain steel makers have high initial Si content (0.6–0.7 wt%) in the hot metal, and with increasing demand for low P steel, new dephosphorization fluxes need to be explored. Addressing this gap, this study investigates red mud's potential as a flux for dephosphorization in hot metal with elevated Si levels. Conducting slag–metal equilibrium experiments at 1350 °C, using red mud‐based fluxes, the research achieves a 40% dephosphorization degree under optimized conditions of double deslagging and fluxing. Analysis via wet chemical methods and inductively coupled plasma mass spectrometry confirms the effectiveness of the approach. Furthermore, thermodynamic calculations highlight the influence of O2 partial pressure and Si content on dephosphorization efficacy. Through laboratory experiments and theoretical insights, this study provides a valuable roadmap for leveraging red mud as a sustainable flux in hot metal dephosphorization processes, contributing to both waste management and steel production efficiency.

The optimal dietary sodium and chloride level for broiler chicks fed a corn-soybean meal diet between 1 and 21 days of age.

The experiment was conducted to estimate the ideal dietary sodium (Na) and chloride (Cl) level for broilers during d 1 to 21 using a corn-soybean meal diet under a dietary Na:Cl ratio of 1:1. A total of 490 one-d-old Arbor Acres male broilers were randomly allotted by bodyweight to 1 of 7 treatments in a completely randomized design. Each treatment consisted of 7 replicate cages with 10 chicks per cage. Broilers were fed a Na and Cl-unsupplemented corn-soybean meal basal diet (control, containing 0.02% Na and 0.08% Cl) and the Na and Cl-supplemented basal diets containing 0.14%, 0.20%, 0.26%, 0.32%, 0.38% and 0.44% Na and Cl levels, respectively for 21 d. The results indicated that average daily gain, average daily feed intake, blood partial pressure of CO2 and concentrations of HCO3-, total CO2, Na+, Cl-, base excess and anion gap, tibial ash and ash Na contents of broilers were affected (P < 0.001) by dietary Na and Cl level, and increased linearly (P < 0.001) and quadratically (P < 0.001) with increasing Na and Cl levels. Feed/gain ratio, mortality, blood K+ concentration, serum osmotic pressure and K+, glucose and uric acid concentrations as well as heart, liver and kidney indices of broilers were affected (P < 0.01) by dietary Na and Cl level, and decreased linearly (P < 0.001) and quadratically (P < 0.001) with increasing Na and Cl levels. The estimates of dietary optimal Na and Cl levels were 0.07%-0.16% according to the best fitted broken-line or asymptotic models (P < 0.001) of the above sensitive indicators. Therefore, the optimal dietary Na and Cl level was suggested to be 0.16% to support all of the above Na and Cl metabolic requirements of broilers fed the corn-soybean meal diet during d 1 to 21, which is lower than the recommendation at 0.20% by the Chinese Feeding Standard of Chicken (2004).

Temporal variations in and predictive values of ABG results prior to in-hospital cardiac arrest

In-hospital cardiac arrest (IHCA) has been understudied relative to out-of-hospital cardiac arrest. Further, studies of IHCA have mainly focused on a limited number of pre-arrest patient characteristics (e.g., demographics, number and types of comorbidities). Arterial blood gas (ABG) analysis, one of the most common diagnostic tests for assessing and managing critically or acutely ill hospitalized patients, reflects pathophysiological changes associated with adverse events or complications, including IHCA. Yet the predictive and prognostic values of patterns of pre-arrest ABG parameters for IHCA have not been fully studied. The purpose of this retrospective pilot cohort study was to investigate temporal variations in and predictive values of pre-IHCA ABG values among patients with a history of cardiopulmonary diseases. Eligible patients had a history of structural heart disease, heart failure, or pulmonary diseases. Patients were excluded if their IHCA was due to trauma, drug overdose, hypothermia, drowning, chronic terminal illness such as cancer or human immunodeficiency virus, or bleeding not caused by hemorrhage in the brain or heart. Also collected were dates, times, and causes of mechanical intubation prior to IHCA and causes of mortality. Co-primary outcomes were initial rhythms of IHCA and return of spontaneous circulation (ROSC). We conducted a pilot study and the ABG results (pH, partial pressure of carbon dioxide [PaCO2], partial pressure of oxygen [PaO2], bicarbonate [HCO3-] , and lactate) from each of the 3 days prior to IHCA were extracted from the electronic health records (EHRs) of patients (N = 44) who had experienced IHCA at a single medical center. To characterize differences in ABG parameters among study days, coefficients of variation (CVs) were compared using the modified likelihood ratio test (MLRT) using the worst ABG values. Linear regression models were run for the continuous ABG parameters and logistic regression models for the dichotomous ABG variables. Overall model effect and least squares means, SDs, mean differences within and between days (with 95 % confidence intervals), p-values and effect sizes were reported for continuous variables. For categorical variables, estimates and standard errors, 95 % confidence intervals, Wald X2 variables and p-values were presented. The CVs for pH, PaCO2, and HCO3- differed significant between study days (p <.05). The least squares means with 95 % confidence intervals for pH and lactate differed significantly in days (p <.01). Moderate to large effect sizes were obtained for all ABG parameters. Arterial lactate predicted initial rhythm (shockable versus non-shockable) and ROSC, while pH and HCO3- predicted ROSC. Results demonstrate, for the first time, the presence of significant variability in ABG parameters across 72 h prior to IHCA and the predictive potential of these parameters for initial rhythms of IHCA and ROSC. While validation in a larger sample is necessary, this study confirms the feasibility and potential value of exploring temporal patterns of pre-arrest ABG values from the EHRs. Findings of future larger studies on pre-arrest patterns of ABG parameters and other laboratory values may be used to design models that better predict risk for IHCA and guide patient care in the pre and intra-arrest periods.

STATE OF HAEMODYNAMICS AND OXYGEN BUDGET IN THE PERIOPERATIVE PERIOD IN PATIENTS WITH OSTEOARTHRITIS AND CONCOMITANT CARDIAC PATHOLOGY DURING TOTAL HIP ARTHROPLASTY SURGERY DEPENDING ON THE TYPE OF SURGICAL ACCESS

Summary. Aim. To compare the hemodynamic status and oxygen budget in patients with osteoarthritis and comorbid cardiac pathology during total hip arthroplasty, based on the type of surgical approach used. Materials and Methods. The study analyzed the treatment outcomes of 90 patients with stage 3-4 osteoarthritis of the hip who underwent total cemented hip arthroplasty. All patients were divided into two groups according to the surgical approach (traditional posterior or modified posterior). The study was conducted at the following stages: before surgery, immediately after surgery, 24 hours post-surgery, and one week after surgery. The following parameters were recorded: hemodynamic parameters (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, and central venous pressure) and oxygen budget parameters (hemoglobin (Hb), lactate, hematocrit (Ht), oxygen saturation of hemoglobin in arterial and venous blood (SaO2 and SvO2), partial pressure of oxygen in arterial and venous blood (paO2 and pvO2)). Based on these data, the following indices were calculated: left ventricular ejection fraction (LVEF), cardiac index (CI); oxygen content in arterial and venous blood (CaO2 and CvO2), arteriovenous oxygen content difference (C(a-v)O2), oxygen transport (TO2), oxygen consumption (VO2); systemic perfusion pressure (SPP), blood flow power (BFP), oxygen reserve (OR), and circulatory reserve (CR). Results. The use of the modified posterior approach positively influenced hemodynamic parameters. After the surgery and on the 7th day post-surgery, SPP was significantly lower with the modified posterior approach. The CI was also significantly affected by the modified posterior approach. Throughout the study, except for the first stage, CI was significantly higher when using the modified posterior approach. LVEF increased significantly with both approaches, but on the 7th day post-surgery, it was significantly higher in the second group. BFP did not statistically differ between the two groups throughout the study, but its energy efficiency was lower, primarily due to the arteriovenous oxygen content difference (C(a-v)O2). C(a-v)O2 was the same before surgery for both approaches. At subsequent stages of the study, the differences between the groups increased, and on the 7th day, they were the most significant, with C(a-v)O2 being lower after using the modified posterior approach. The energy efficiency of blood flow was assessed by calculating OR and CR. Both indicators were significantly higher during the study, except at the preoperative stage, when using the modified posterior approach. Conclusions. Our study clearly demonstrates the benefits of implementing the modified posterior approach in total hip arthroplasty for patients with osteoarthritis and comorbid cardiac pathology. This approach improves hemodynamic and oxygen budget parameters compared to the traditional approach, which can significantly impact treatment outcomes for patients with cardiac comorbidity and reduce the number of postoperative complications.

The mayfly Neocloeon triangulifer senses decreasing oxygen availability (PO2) and responds by reducing ion uptake and altering gene expression.

Oxygen availability is central to the energetic budget of aquatic animals and may vary naturally and/or in response to anthropogenic activities. Yet, we know little about how oxygen availability is linked to fundamental processes such as ion transport in aquatic insects. We hypothesized and observed that ion (22Na and 35SO4) uptake would be significantly decreased at O2 partial pressures below the mean Pcrit (5.4 kPa) where metabolic rates (MO2) are compromised, and ATP production is limited. However, we were surprised to observe marked reductions in ion uptake at oxygen partial pressures well above the Pcrit, where MO2 was stable. For example, SO4 uptake decreased by 51% at 11.7kPa, and 82% at the Pcrit (5.4kPa) while Na uptake decreased by 19% at 11.7kPa, and 60% at the Pcrit. Nymphs held for longer time periods at reduced PO2 exhibited stronger reductions in ion uptake rates. Fluids from whole body homogenates exhibited a 29% decrease in osmolality in the most hypoxic condition. The differential expression of atypical guanylyl cyclase (gcy-88e) in response to changing PO2 conditions provides evidence for its potential role as an oxygen sensor. Several ion transport genes (e.g., chloride channel and sodium-potassium ATPase) and hypoxia-associated genes (e.g., ldh and egl-9) were also impacted by decreased oxygen availability. Together, our work suggests that N. triangulifer can sense decreased oxygen availability and perhaps conserves energy accordingly, even when MO2 is not impacted.

Potential Impacts of Dried Green Coleus forskolin Leaves on Thermo-tolerance Parameters, Blood and Plasma Profiles in Anesthetized Mice

Background: Transient negative side effects of hypothermia, hyperglycemiaand bradycardia due to general anesthesia using diazepam and xylazine drugs has been reported in mice. Methods: Twenty albino male mice of 31.52±0.25 g body weight were classified into two groups; control group (G1) fed basal control diet versus C. forskolin group fed basal control diet containing C. forskolin leaves (G2; 1.5%) for four weeks. The mice were general anesthetized using xylazine and diazepam (XD) drugs (13.3 mg/kg BW diazepam and 26.6 mg/kg BW xylazine). Changes of rectal temperature (°C), glucose (mg/dl), pulse rate (pulse/min.) and partial pressure of oxygen (SPO2) were recorded at 0.0, 0.5h, 1.0h, 2.0h, 3.0h, 5.0h and 7.0h over general anesthesia. In addition, blood samples were collected and were subjected to blood and plasma analyses. Result: The results indicated that dietary C. forskolin caused significant decrease (P less than 0.05) in glucose values in addition to significant increase (P less than 0.05) in rectal temperature, pulse rate and SPO2 during the period hypothermia, hyperglycemiaand bradycardia over general anesthesia. In addition, values of blood (RBCs, WBCs, PCV and Hb) and plasma parameters (TP, BUN, creatinine, AST and ALT, LDH) were normal due to C. forskolin supplementation compared to control diet. It could be concluded that 1.5% C. forskolin supplementation modulates thermo-tolerance responses, blood glucose indices, blood and plasma metabolites over general anesthesia.

Predicting Survival Status in COVID-19 Patients: Machine Learning Models Development with Ventilator-Related and Biochemical Parameters from Early Stages: A Pilot Study.

Objective: Coronavirus disease 2019 (COVID-19) can cause intubation and ventilatory support due to respiratory failure, and extubation failure increases mortality risk. This study, therefore, aimed to explore the feasibility of using specific biochemical and ventilator parameters to predict survival status among COVID-19 patients by using machine learning. Methods: This study included COVID-19 patients from Taipei Medical University-affiliated hospitals from May 2021 to May 2022. Sequential data on specific biochemical and ventilator parameters from days 0-2, 3-5, and 6-7 were analyzed to explore differences between the surviving (successfully weaned off the ventilator) and non-surviving groups. These data were further used to establish separate survival prediction models using random forest (RF). Results: The surviving group exhibited significantly lower mean C-reactive protein (CRP) levels and mean potential of hydrogen ions levels (pH) levels on days 0-2 compared to the non-surviving group (CRP: non-surviving group: 13.16 ± 5.15 ng/mL, surviving group: 10.23 ± 5.15 ng/mL; pH: non-surviving group: 7.32 ± 0.07, survival group: 7.37 ± 0.07). Regarding the survival prediction performanace, the RF model trained solely with data from days 0-2 outperformed models trained with data from days 3-5 and 6-7. Subsequently, CRP, the partial pressure of carbon dioxide in arterial blood (PaCO2), pH, and the arterial oxygen partial pressure to fractional inspired oxygen (P/F) ratio served as primary indicators in survival prediction in the day 0-2 model. Conclusions: The present developed models confirmed that early biochemical and ventilatory parameters-specifically, CRP levels, pH, PaCO2, and P/F ratio-were key predictors of survival for COVID-19 patients. Assessed during the initial two days, these indicators effectively predicted the likelihood of successful weaning of from ventilators, emphasizing their importance in early management and improved outcomes in COVID-19-related respiratory failure.

Transported Entropy of Ions and Peltier Coefficients in 8YSZ and 10Sc1CeSZ Electrolytes for Solid Oxide Cells.

In this study, the transported entropy of ions for 8YSZ and 10Sc1CeSZ electrolytes was experimentally determined to enable precise modeling of heat transport in solid oxide cells (SOCs). The Peltier coefficient, crucial for thermal management, was directly calculated, highlighting reversible heat transport effects in the cell. While data for 8YSZ are available in the literature, providing a basis for comparison, the results for 10Sc1CeSZ show slightly smaller Seebeck coefficients but higher transported ion entropies. Specifically, at 700°C and an oxygen partial pressure of pO2=0.21 bar, values of SO2-*=52±10 J/K·F for 10Sc1CeSZ and SO2-*=48±9 J/K·F for 8YSZ were obtained. The transported entropy was also validated through theoretical calculations and showed minimal deviations when comparing different cell operation modes (O2||O2-||O2 and H2, H2O||O2-||O2). The influence of the transported entropy of the ions on the total heat generation and the partial heat generation at the electrodes is shown. The temperature has the greatest influence on heat generation, whereby the ion entropy also plays a role. Finally, the Peltier coefficients of 8YSZ for all homogeneous phases agree with the literature values.

Strain Effects on the Adsorption of Water on Cerium Dioxide Surfaces and Nanoparticles: A Modeling Outlook.

Nanocrystalline ceria exhibits significant redox activity and oxygen storage capacity. Any factor affecting its morphology can tune such activities. Strain is a promising method for controlling particle morphology, whether as core@shell structures, supported nanoparticles, or nanograins in nanocrystalline ceria. A key challenge is to define routes of controlling strain to enhance the expression of more active morphologies and to maintain their shape during the lifespan of the particle. Here, we demonstrate a computational route to gain insights into the strain effects on particle morphology. We use density functional theory to predict surface composition and particle morphology of strained ceria surfaces, as a function of environmental conditions of temperature and partial pressure of water. We find that adsorbed molecular water is not sufficient to shift stability and as such under all compressive and tensile strains studied, the most stable particle is of octahedral shape, similarly to the unstrained case. When dissociative water is involved at the surfaces of the particle, then the most stable particle morphology changes under high water coverage and tensile strain to cuboidal or truncated cuboidal shapes. This shift in shape is due to strain effects that affect the strength of water adsorption.

Impact of temperature humidity index (THI) on blood gas and electrolytes of dairy cows in late gestation

The study was carried out to assess the impact of heat stress on dairy cows in late gestation and their newborn calves. Study was conducted in two phases in crossbred cattle during last trimester of pregnancy, maintained in University Livestock Farm and Fodder Research Development Scheme, Mannuthy, KVASU. December to February with minimum THI was taken as season 1 and March to May with maximum THI as season 2 of the study. Microclimatic data in the animal shed was recorded three times at three days intervals. The ambient temperature, relative humidity and THI obtained during season 2 was significantly (p&lt;0.01) higher than season 1 in both macro and microclimatic data. Partial pressure of carbon dioxide (pCO2 ) was low in season 2 but there was no significant difference in potassium (K+), sodium (Na+), bicarbonate (HCO3 - ) and partial pressure of oxygen (pO2 ) between the seasons. Keywords: Heat stress in cattle, THI, blood gases, electrolytes, late gestation

Transcutaneous carbon dioxide monitoring in children undergoing rigid bronchoscopy: a prospective blinded observational study.

Anesthetic management during rigid bronchoscopy in children can be challenging, and continuous end-tidal carbon dioxide (EtCO2) monitoring is often unachievable. Transcutaneous carbon dioxide (TcCO2) monitoring is strongly correlated with the partial pressure of carbon dioxide (PaCO2) and EtCO2. We aimed to investigate the incidence of hypercapnia in children undergoing rigid bronchoscopy. We enrolled patients aged < 18yr scheduled for rigid bronchoscopy in a prospective observational study. We recorded TcCO2 values from anesthesia induction to the postanesthesia care unit (PACU) stay. We ended monitoring when TcCO2 reached values ≤ 50mm Hg. The operating room (OR) team was blinded to the TcCO2. The outcome of primary interest was the incidence of hypercapnia (TcCO2 > 50mm Hg) in the OR. Other outcomes were the incidences of hypercapnia in the PACU and severe hypercapnia (TcCO2 > 90mm Hg), factors possibly related to hypercapnia (patient, surgery, or anesthesia factors), and the incidence of perioperative adverse events. A total of 30 patients were enrolled. The median [interquartile range (IQR)] age was 3.5 [1.5-8.0] yr. The incidence of hypercapnia was 100% in the OR and 60% in the PACU. Five cases (17%) presented with severe hypercapnia in the OR. The highest median [IQR] TcCO2 was 69 [61-79] mm Hg. The most common adverse event was oxygen desaturation (57%, 17/30). Patients with severe hypercapnia had long stays in the PACU. Hypercapnia was a frequent event in children undergoing rigid bronchoscopy and severe hypercapnia was associated with a long PACU stay. Further studies are needed to assess the utility of TcCO2 monitoring in guiding ventilatory interventions during these cases.