Gas Analysis Research Articles

Neonatal Hypoglycaemia Management Guideline appraisal using the AGREE II instrument and report of variations in unit guidelines in Australia and New Zealand.

To assess the quality and rigour of Neonatal Hypoglycaemia guidelines used in the major Australian and New Zealand neonatal care centres. To compare and highlight any major differences in management guidelines between centres. All level III NICUs in Australia and New Zealand were invited to participate. The AGREE II (Appraisal of Guidelines, Research & Evaluation) was used to critically appraise the guideline for the management of neonatal hypoglycaemia. Recommendations regarding definition, treatment, method of testing and admission criteria were compared from the guidelines provided. Neonatal Hypoglycaemia guidelines were received from 19 of the 29 invited hospitals; two guidelines were excluded as the hospitals providing these guidelines did not provide care for inborn neonates. None of the 17 guidelines received a standardised score of 50% or higher on all six domains of the AGREE II tool. The mean scores of each of the AGREE II domains were as follows: Scope and Purpose 76%; Stakeholder Involvement 41%; Rigour of Development 20%; Clarity of Presentation 66%; Applicability 30% and Editorial Independence 0.1%. The glycaemic threshold defining hypoglycaemia varied between 2.0 and 2.6 mmol/L in the guidelines. True blood glucose using either a glucose oxidase method or blood gas analyser was recommended as the first line test in 35% of the guidelines. Fifteen of the 17 guidelines recommended buccal gel as first-line treatment of hypoglycaemia. Neonatal Hypoglycaemia guidelines are of varying methodological quality. There are inconsistences in the management of hypoglycaemia across neonatal units in Australia and New Zealand.

Assessing transformer health through analysis of dissolved gases in cooling oil

Gases can form within the insulation system for various reasons while a transformer is in operation. If these gases are not promptly and properly managed, they can negatively impact the transformer's performance. Using the dissolved gas analysis (DGA) method to identify and assess the type and quantity of dissolved gases in transformer oil can uncover potential issues within the transformer. This information is crucial for guiding preventive maintenance and necessary repairs. Dissolved gas analysis testing was conducted by extracting transformer oil samples to identify signs of disturbances in the transformer based on the dissolved gas content. This research was conducted at the Paiton plant operations and maintenance services division. The condition of transformers was assessed by analyzing dissolved gases using the Rogers ratio method. Results indicate that the transformer at Paiton 9 is in good condition but overheating has occurred and requires treatment. Conversely, the transformers at Paiton 1 and 2 are in poor condition, showing signs of electrical faults and excessive heat. Despite several attempts to add inhibitors and conduct frequent testing, the transformers remained in poor condition, necessitating their replacement or repair.

A novel agrosinters support growth, photosynthetic efficiency and reduce trace metal elements accumulation in oilseed rape growing on metalliferous soil

Soil conditioners to fertilize, improve soil structure and support the phytostabilization of trace metal elements (TMEs) are being used more and more frequently. One of the options are agrosinters – slow-release ceramic fertilizers consisting mainly of SiO2, CaO, P2O5 and K2O, with an alkaline pH and high impact strength. The effect of two different agrosinters, A1 and A2, on the growth and physiological condition of Brassica napus grown in uncontaminated and Pb-, Cd- and Zn-contaminated soil was investigated in a pot experiment. In vivo data were collected using an infrared gas analyzer, a fluorimeter, a pigment content meter and a thermal camera. Elemental composition of the biomass was also investigated. The tested agrosinters promote biomass yield and have an effect on improving leaf chlorophyll content, phenomenological energy fluxes and plant gas exchange. The effect of the agrosinters on the plants was dose- and amendment-specific. An immobilization effect was observed not only in the soil but also in the plants. A reduction in the Cd (22%) and Zn (40%) content in the biomass was measured. All this was related to the effect of increasing the available form of P (50%), K (300%) and Ca (50%) in the soil, which improves soil fertility and reduces the bioavailable forms of the studied TMEs, due to the increase in soil pH and/or the complexation of these with phosphate compounds. The multidimensional analysis of A2 agrosinter shows the most positive effects on plant conditions, indicating that fly ash as a mixed substrate benefits the plants.

Incidence of ketoacidosis in diabetic patients treated with sodium–glucose cotransporter-2 inhibitors: A prospective cohort study

Introduction: Sodium–glucose cotransporter 2 inhibitors (SGLT2is) have gained significant attention for their benefits in managing type 2 diabetes mellitus (T2DM), particularly in patients with chronic kidney disease (CKD) and heart failure. However, the potential for SGLT2is to increase the risk of ketoacidosis, particularly euglycemic diabetic ketoacidosis (EDKA), warrants further investigation. This prospective cohort study assesses the incidence of ketoacidosis among T2DM patients treated with SGLT2is and examines related risk factors. Methods: This is a prospective study included 575 patients with T2DM. Patients over 18 years undergoing SGLT2i therapy were followed for six months. Baseline demographics, clinical history, glucose management practices, and medication use, with an emphasis on SGLT2is, were recorded. Blood gas analysis (BGA) and urine ketones were measured monthly. Ketoacidosis was defined by urine ketone positivity with pH <7.30, bicarbonate (HCO3) ≤18 mEq/L, and an elevated anion gap. Results: Out of 575 patients, 35.6% (205) had positive urine ketones at least once during the study, with 11 patients (0.7%) meeting ketoacidosis criteria. Patients with ketoacidosis had a mean hospital stay of 8.2 days compared to 5.4 days in non-ketoacidosis patients (p = 0.02). No in-hospital mortality occurred among ketoacidosis patients. Conclusion: Ketoacidosis was rare but clinically relevant in T2DM patients on SGLT2is. The incidence of euglycemic ketoacidosis highlights the need for monitoring and identifying high-risk individuals early during SGLT2i treatment initiation.

Liver failure after Bacillus cereus food poisoning, an under-recognized entity: A case report

BACKGROUND Bacillus cereus (B. cereus ) is known to cause 2 types of foodborne diseases; the diarrheal and emetic syndromes. They are largely underreported due to their usually self-limiting course. Rare and sometimes fatal cases of liver failure, pulmonary hemorrhage and cerebral oedema have been reported mainly in children and young adults. We present here a case of liver failure associated with B. cereus food poisoning in a middle-aged patient. CASE SUMMARY A 48-year-old female patient presented to the emergency department for emesis, diarrhea, chills without fever, asthenia and diffuse abdominal cramps that started less than 30 minutes after eating a rice salad. Her past medical history was relevant for cholecystectomy and a cured Hashimoto’s disease. She did not take any medication, drugs and declared a consumption of one glass of wine per week. In the emergency department, she was treated with acetaminophen, metoclopramide, ondansetron, and an intravenous normal saline infusion. Blood gas analysis revealed a metabolic acidosis with hyperlactatemia, coagulation revealed a low prothrombin activity [32 %; normal values (N): 70-140] and a low Factor V activity (15%; N: > 70). Transaminases were elevated with hyperbilirubinemia, elevated lipase and rhabdomyolysis. N-acetylcysteine treatment was introduced. Abdominal echography revealed no signs of chronic hepatopathy or hepatomegaly. Day after the admission, psychomotor activity improved, transaminases and lipase started decreasing. Rhabdomyolysis gradually worsened to peak on day 3. Screening tests for liver disease were negative for viral and autoimmune cause of liver failure. Stools cultures were positive for colonies of the B. cereus group which were also identified in the rice salad samples processed whereas blood cultures were negative. The patient’s condition improved gradually including her liver function parameters and psychomotor activity which allowed her discharged home on day 9. CONCLUSION We describe a rare case of hepatocellular dysfunction due to a foodborne B. cereus intoxication in an adult patient. Even if it is uncommon, the severity of liver dysfunction reported and mechanism of the cereulide toxin toxicity on liver suggest that acetaminophen should be avoided in case of a foodborne intoxication and n-acetylcysteine could be a potential therapy helping to prevent hepatocytes necrosis due to the oxidative stress induced by mitochondrial dysfunction.

Interplay Between Unburned Emissions and NOx Emissions From a Dual Swirl Hydrogen Air Injector

Abstract OH planar laser induced fluorescence (OH-PLIF) and particle image velocimetry (PIV) are employed to analyze the structure of hydrogen/air flames stabilized by a dual swirl injection system under globally lean and atmospheric conditions with preheat air temperature varied from ambient up to 673 K. The flames exhibit two distinct reaction branches. The first, located in the central recirculation zone (CRZ), is a diffusion-controlled reaction layer characterized by a relatively large thickness associated with low strain rates. The second branch, stabilized in the shear layer of the swirling jet, is strongly influenced by large coherent structures. Depending on operating conditions, this front may adopt either the form of a fully diffusive strained reaction layer anchored to the hydrogen injector lip or a lifted diffusion front with a leading-edge flame evolving into a partially premixed flame at high air injection velocities. Flue gas analysis indicates NOx emission levels, typically below 10 ppm at 15% O2, for sufficiently large air injection velocities. Air preheating barely increases NOx emissions at lean operating conditions. The injector operational range is constrained only by the ultralean blowout limit reached for global equivalence ratios below 0.02. Furthermore, it demonstrates remarkable resilience to large and rapid drop in fuel flow rate. However, combustion efficiency drops close to the lean blowout (LBO) limit due to intermittent fragmentation of the flame wings that progresses further upstream as the equivalence ratio drops. The results demonstrate that fragmentation arises from the combined effects of a temperature drop in the central recirculation zone and the flame wings being exposed to high shear stress. Additionally, it is shown that combustion efficiency under ultralean conditions improves significantly with an increase in air preheat temperature.

Effect of the Concentration of Bioethanol Mixed with Gasoline on the Energy and Environmental Performance of a Hybrid Vehicle in the Worldwide Harmonized Light Vehicles Test Cycle (WLTC)

Increasing the use of renewable biofuels in internal-combustion-engine (ICE) vehicles is a key strategy for reducing greenhouse gas emissions and conserving fossil fuels. Hybrid vehicles used in urban environments significantly reduce fuel consumption compared to conventional internal-combustion-engine cars. In hybrid vehicles integrating electric propulsion with biofuels offers even more significant potential to lower fuel consumption. One would like to think they should also be less polluted in all cases, but some results show that the opposite is true. This study’s aim was to evaluate a hybrid vehicle’s energy and environmental performance using different gasoline–bioethanol blends. A Worldwide Harmonized Light Vehicles Test Cycle (WLTC) study was conducted on a Toyota Prius II hybrid vehicle to assess changes in energy and environmental performance. During the WLTC test, data were collected from the chassis dynamometer, exhaust gas analyser, fuel consumption meter, and engine control unit (ECU). The collected data were synchronised, and calculations were performed to determine the ICE cycle work, brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), pollutant emissions (CO, HC, and NOx), CO2 mass emissions per cycle, and brake specific pollutant emissions per kilometre. The study shows that the performance of the hybrid vehicle’s ICE is strongly influenced by the utilisation of electrical energy stored in the battery, especially at low and medium speeds. As the bioethanol concentration increases, the engine’s ECU advances the ignition timing based on the knock sensor signal. A comprehensive evaluation using the WLTC indicates that increasing the bioethanol concentration up to 70% improves the energy efficiency of the hybrid vehicle’s internal combustion engine and reduces pollutant and CO2 emissions.

The Unit Auxiliary Transformer Analysis By Dissolve Gas Analysis and Breakdown Voltage Test

The Unit Auxiliary Transformer Analysis By Dissolve Gas Analysis and Breakdown Voltage Test

Eddy covariance with slow-response greenhouse gas analysers on tall towers: bridging atmospheric and ecosystem greenhouse gas networks

Abstract. Greenhouse gas monitoring is important to ensure climate goals are being achieved. This study unveils the potential of using atmospheric tall towers in direct flux measurements, bridging the gap between atmospheric and ecosystem monitoring networks. The ICOS Cities (PAUL) project aims to monitor CO2 emissions in urban areas, where concentrated emissions make them key targets for climate change mitigation. This study explores the synergy between ICOS atmospheric and ecosystem networks by utilizing slow-response analysers (∼ 3 s) on tall atmospheric towers for ecosystem studies using the eddy covariance method. A standard setup with an ultrasonic anemometer and an infrared (IR) fast-response CO2 analyser was installed and compared with measurements from an existing cavity ring-down spectroscopy (CRDS) analyser measuring CO2, CO, and CH4. Deployed on the 100 m Saclay tower near Paris, covering a 43.9 km2 80 % footprint with heavy traffic roads, a nearby heating plant, and a forest, the setup addressed technical challenges and height-induced complexities. Corrections for flux attenuation by high-frequency losses were limited to < 20 % on average for all stabilities and around 11 % for unstable conditions. Elevated mean fluxes for CO2 (10 µmolm-2s-1) and CH4 (200 µmolm-2s-1) were observed from the heating plant wind direction during December and January. Conversely, the forest direction exhibited the strongest sink among all wind directions, with −4 µmolm-2s-1 during July and August. Storage and vertical advection were estimated using the routine three-level profile measurements done in ICOS atmospheric towers. Storage term was of the same magnitude as turbulent flux, increasing at night and de-stocking during the first half of the day. Vertical advection averaged zero on a monthly basis. These results demonstrate the feasibility and versatility of utilizing atmospheric towers for urban emission monitoring, offering valuable insights for emission monitoring strategies worldwide.

Aeration Optimization for the Biodrying of Market Waste Using Negative Ventilation: A Lysimeter Study

This study investigates the optimization of aeration rates for the biodrying of market waste using negative-pressure ventilation. Market waste, characterized by a high moisture content (MC) and rapid decomposition, presents challenges in waste management. Over 12 days, three aeration rates (ARs) of 0.2, 0.4, and 0.6 m3/kg/day were examined, and the most effective continuous ventilation configuration was identified in terms of heat generation, moisture reduction, and biodrying efficiency. The results indicate that the most effective AR for heat retention and moisture removal was 0.2 m3/kg/day, achieving a 6.63% MC reduction and a 9.12% low heating value (LHV) increase. Gas analysis showed that, while AR 0.2 supported high microbial activity during the initial 7 days, AR 0.6 sustained higher overall CO2 production due to its greater aeration rate. The findings also suggest that the biodrying of market waste with a high initial MC can achieve significant weight loss and leachate generation when paired with a high aeration rate of 0.6 m3/kg/day, with a 69.8% weight loss and increased waste compaction being recorded. The study suggests that variable ARs can optimize biodrying, making market waste more suitable for conversion to refuse-derived fuel or landfill pre-treatment and improving waste-to-energy processes and sustainability.

Influence of Clear Felling on СО2 Emission from the Podzolic Soil Surface of the Coniferous-Deciduous Forest (Middle Taiga, Komi Republic)

The impact of industrial logging on the carbon cycle of boreal forests is characterized by significant uncertainties, which is largely due to the lack of information on carbon fluxes (in particular, soil respiration) in felling sites. The aim of study is to assess the effect of clear felling on CO2 emission from the soil surface of a coniferous-deciduous forest on a typical podzolic soil (Albic Retisol). The investigation was executed during the snowless periods (May-October) of 2020–2022 in a coniferous-deciduous forest and its felling site carried out in the winter of 2020. The carbon dioxide emission was measured by a LI COR 8100 gas analyzer. A brief description of the weather conditions during the years of research and the dynamics of soil temperature at a depth of 10 cm is given. A positive, statistically significant relationship between soil respiration and soil temperature at a depth of 10 cm (R2 = 0.17–0.75; p 0.001) was detected for the analyzed objects. The correlation with soil moisture was both positive and negative and statistically insignificant except data obtained in 2022 in the undisturbed control forest. The high values of CO2 flux during the snowless period were observed in July–August and was 3.90–5.62 gC/ m2/ day and 2.3–2.5 gC/m2/day in undisturbed forests and felled areas, respectively. In 2021, the peak of CO2 release shifted to June. Clear felling has a negative effect on the soil respiration of Albic Retisol that decreased by 1.2–1.9 times in the conditions of the middle taiga of the Komi Republic. The most (55–66%) of the C–CO2 efflux during the snowless period was emitted during the summertime, and the vegetation period (May–September) contribution was 84–88%. The obtained data will serve to determine the role of industrial logging in the carbon cycle of taiga forests.

Typical causes and clinical presentations of traumatic and nontraumatic soft tissue and organ haemorrhage in emergency departments

Acute bleeding often occurs in awide variety of forms in clinical emergency medicine. In traumatic bleeding, soft tissue injuries to the head or extremities are common, while severe bleeding is less common in chest injuries or pelvic trauma. In nontraumatic emergencies, gastrointestinal bleeding is the leading cause, but many other bleeding entities are possible. Structured management helps to detect the critically ill patient, identify the possible source of bleeding and provide appropriate radiological diagnostics and therapy. Clinical examination, blood gas analyses and emergency ultrasound are crucial in the initial phase of diagnosis. Initially, symptomatic therapy is usually indicated to stabilize the patient, and then interventional or surgical care is indicated in the course of the disease, depending on the location of the bleeding. Volume and catecholamine therapy, coagulation management and emergency transfusion are important components of interdisciplinary emergency care, in addition to primary bleeding control, especially in the case of open injuries.

Comprehensive Investigation of Epoxy Adhesives for Structural Applications in Saudi Arabia: Mechanical Performance, Environmental Impacts, and Analysis on Health.

Epoxy adhesives possess excellent mechanical properties, durability, and stability in harsh environments, making them suitable for producing engineering materials. This study selects four commercially available epoxy adhesives in Saudi Arabia: Epotec YD 128; Sikadur®-52 LP; Sikadur®-31 CF; and Sikadur®-42 MP Slow. Firstly, a comparison of their storage, application, and service temperatures was made, detailing the hazard identification and prevention measures established in accordance with the Occupational Safety and Health Administration (OSHA) guidelines. Subsequently, test samples of the four adhesives were produced, and tensile, compressive, and shear tests were conducted to compare their fundamental mechanical properties. Finally, a gas analyzer assessed the major harmful gases emitted by these epoxy adhesives 120 min after mixing the epoxy resins and curing agents. The results show that Sika 42 exhibits the highest tensile and compressive strengths among other types of adhesives, reaching 75.7 MPa and 133.8 MPa, respectively. It also has the longest pot life of 48 min at elevated temperatures (40 °C), making it suitable for the climatic conditions in Saudi Arabia. However, as a three-component adhesive, its application is complex and associated with the most identified hazards. Sika 31 presents a tensile modulus of up to 10.4 GPa, at least 3.8 times higher than the other adhesives, making it practical for controlling tensile deformation. Additionally, its ultimate shear strain reaches 10.7%, at least 6.6 times higher than the other samples, highlighting its suitability for constructing ductile bonds. After mixing of epoxy resins with curing agents, the presence of NO2 and SO2 were detected. However, no harmful gases were detected after 120 min, possibly due to the complete curing of the adhesives.

Kinetic Modeling in Temperature-Modulated Semiconductor Gas Sensor Utilizing Eley-Rideal Mechanism and Its Application in Discriminative Detection of VOCs.

This study presents a comprehensive kinetic investigation for describing the dynamic sensing process of semiconductor metal oxide (SMO)-based gas sensors, with a focus on the Eley-Rideal mechanism as a valid pathway. The modeling elucidates the direct interactions between volatile organic compounds (VOCs) and adsorbed oxygen on the material surface, providing insights into the temperature-dependent response characteristics of the sensor and addressing selectivity toward different VOCs fundamentally. By incorporating the effects of thermal modulation, the kinetic model was validated through theoretical fitting of experimental data obtained from a fabricated SnO2 nanoparticle gas sensor exposed to ethanol, n-propanol, toluene, and butanone at systematically varying operating temperatures. The results demonstrated that the model accurately captures response transient values, enabling a general framework for qualitatively discriminating specific gases based on their unique reaction kinetics. Furthermore, a machine learning procedure containing the above model and power laws of quantitative concentrations after identifying compounds was developed for the prediction of target VOCs. The qualitative accuracy was determined to be 99.4%, while quantifying with the mean absolute errors of 5.0, 7.5, 4.0, and 8.9 within the range of 25-200 ppm, respectively. The precise and straightforward strategy facilitates the response modeling of SMO-based gas sensors, offering a valuable platform for the designing model-driven algorithms applicable in gas analysis and monitoring.

High-intensity interval training is an effective exercise mode to maintain normal blood pressure during pregnancy: a randomized control trial

Pregnant women are more susceptible to high blood pressure (BP) than the general adult population; therefore, all means of preventing this condition should be considered. High-intensity interval training (HIIT) is effective in this regard in the general population, but there is a lack of evidence of its effectiveness during pregnancy. This study aimed to compare an 8-week HIIT program to self-performed moderate-to-vigorous physical activity among pregnant women by evaluating changes in BP after a maximal progressive cardiorespiratory exercise test (CPET) performed at pre-intervention and post-intervention time points. A total of 54 Caucasian women in uncomplicated, singleton pregnancies (age 32 ± 4 years, 22 ± 4 weeks of gestation; M ± SD) with normal BP values completed the interventions. The experimental (HIIT) group (n = 34) completed an online supervised HIIT program consisting of three sessions per week and supplemented by an educational class once per week. Participants in the education (EDU) group (n = 20) attended an educational class once per week and were encouraged to perform moderate-to-vigorous physical activity (PA) on their own. Pre- and post-intervention, all women underwent a CPET on a cycle ergometer with a respiratory gas analyzer. On the day of the CPET, maternal systolic and diastolic BP (mmHg) was measured at rest (before the CPET) and approximately 60 min after the CPET using an electronic BP monitor. Identical CPET and BP measurement protocols were employed for both the HIIT and EDU groups at the pre- and post-intervention time points. Pre-intervention, the HIIT and EDU groups both showed a decrease in systolic and diastolic BP after the CPET, though only the change in systolic BP was statistically significant (HIIT group: p = 0.01; EDU group: p = 0.001). Post-intervention, there were no significant differences in either group between resting and post-CPET BP. There were significant post-intervention differences in VO2peak (p < 0.001) and HRmax (p = 0.002) between the HIIT and EDU groups. From pre- to post-intervention, the EDU and HIIT groups both showed decreases in resting systolic or diastolic BP; there was a significant difference in systolic BP in the EDU group (p = 0.005) and a significant difference in diastolic BP in the HIIT group (p = 0.03). Both groups maintained normal BP values throughout the experiment. However, HIIT, in addition to maintaining normotension, improved cardiorespiratory fitness in pregnant women. It seems that both supervised HIIT and self-performed moderate-to-vigorous PA can be recommended as strategies to prevent BP disorders during pregnancy. More studies are needed to confirm our findings.Trial registration The full study protocol was registered in ClinicalTrials.gov (NCT05009433).

Assessing the Role of Blood Gas Analysis in COVID-19 Patients for Early Warning and Clinical Guidance.

To assess the role of blood gas analysis as an auxiliary tool for detecting and predicting the progression of COVID-19 in patients. A consecutive cohort study was conducted of 106 patients diagnosed with the novel coronavirus. Patients were divided into two groups based on age and the course of the disease (mild to moderate and severe). Blood gas analysis parameters were measured for all participants and results were compared between groups. This study was conducted in the Department of Laboratory Medicine, The Third Affiliated Hospital, Southern Medical University, Guangzhou, China. Arterial/alveolar oxygen partial pressure ratio, reduced hemoglobin fraction, sodium ion, lactic acid, oxygen saturation, oxygen partial pressure, and oxyhemoglobin fraction. Findings indicated statistically significant differences between the two groups in the measured parameters. Blood gas analysis has the potential to more accurately assess the progression of COVID-19 in elderly patients, specifically related to respiratory and acid-base balance issues. This study underscores the importance for bedside nurses to pay close attention to acid-base balance, lung ventilation/ventilation function, and hypoxia status in elderly critically ill patients with COVID-19, in order to more effectively diagnose and predict the progression of the disease.

Depolymerization and Etching of Poly(lactic acid) via TiCl4 Vapor Phase Infiltration.

This study investigates the use of TiCl4 vapor phase infiltration (VPI) to cleave ester groups in the main chain of a polymer and drive depolymerization and film etching. Prior investigations have demonstrated that the infiltration of TiCl4 into PMMA results in dealkylation of its ester bond, cleaving its side groups. This study investigates the VPI of TiCl4 into poly(lactic acid), which is a prototypical polymer with an ester group in its main chain. Utilizing in situ quartz crystal microbalance (QCM) measurements and spectroscopic ellipsometry, PLA is observed to depolymerize readily at 135 °C with extended TiCl4 precursor exposure, resulting in significant thickness and mass reduction, whereas at 90 °C, depolymerization is significantly slower and etching is negligible. Utilizing Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and a residual gas analyzer (RGA), dealkylation is shown to be the primary depolymerization mechanism. FTIR and XPS analyses reveal the consumption of carbonyl and methoxy groups and the emergence of hydroxyl, chlorine, and titanium moieties. In situ RGA measurements provide further insights into the byproducts formed during the TiCl4 and water exposure steps, indicating that the depolymerized components undergo further breakdown into other substances. Residuals left after 135 °C TiCl4 VPI are easily removed with a 0.1 M HCl aqueous solution. These findings highlight the expanding functionality of VPI, revealing its capability as both an additive and subtractive process and suggesting its broader applications.

HPB O04 - Human Splenic Ex-Vivo Perfusion Model: A Platform for Translational Basic Science Research

Abstract Background The function of the spleen has always been shrouded in mystery and since the Renaissance leading figures have attempted to understand its function. Vesalius questioned Galen and Marcello Malpighi (1628-1694) gave the first accurate description of the histology and the physiology. The spleen still poses unique challenges as invasive approaches may produce intraperitoneal bleeding, differences between human and animal spleens complicates comparative studies, and post-mortem examinations reveal only late-stage disease manifestations and functional studies are impossible. This study describes a human splenic ex-vivo perfusion model for translational research, using microbiological studies as markers of splenic physiological function. Method Patients with left-sided pancreatic cancers scheduled for distal pancreatic and splenic resection were identified from the Hepato-Pancreatic and Biliary MDT at the University Hospitals of Leicester NHS Trust. Patients were informed, consented, and the surgical approach remained standard, with splenic artery ligation deferred until specimen extraction. The artery was cannulated, and residual blood clots were cleared with Custodiol® HTK solution. The perfusion technique employs an extracorporeal circuit incorporateing anoxygenator and a heated water chamber maintaining a 37°C perfusate. The perfused spleen was infected with Streptococcus Pneumoniae strains, with regular biopsies and perfusate gas analysis performed. Results Since February 2023, nine spleens have been successfully perfused, with an average weight of 169.5 grams, cold ischemic time of 116 minutes, and warm ischemic time of 12.2 minutes. Pressure was maintained at 80 mmHg and hourly perfusate gas analysis demonstrated a mean pH of 7.1 and a gradual increase in lactate. Histopathological examination revealed clear distinctions between the lymphoid tissue and splenic red pulp, with intact central arterioles and healthy cell morphology at time 0 and after 6 hours of perfusion. Additionally, the perfused spleens cleared S. pneumoniae strains to below-detection levels. Conclusion Our work demonstrates that a stable human splenic ex-vivoperfusion model which maintains structural and physiological integrity can be achieved from tissue that would otherwise be discarded. The continued physiological function is confirmed by the clearance of S. pneumoniae. While currently employed for microbiological studies, this model has the potential to facilitate a wide range of different translational science studieswhile reducing the need for animal experimentation. The perfusion times employed for the present study were sufficient to demonstrate bacterial clearance which was the aim but there is capacity in the system to significantly prolong the duration.

Suggested guide to using lactate gap as a surrogate marker in the diagnosis of ethylene glycol overdose.

Ethylene glycol (EG) poisoning, if not diagnosed rapidly, can lead to poor patient outcomes. Gas Chromatography (GC) is primarily used for EG quantitation which is rarely available, and the turn-around time may be prolonged. Most lactate results from point-of care (POCT) methods are falsely elevated in EG poisoning compared with automated chemistry analyser results. In combination the lactate gap (POCT-Automated chemistry) can be used as surrogate marker in just about all laboratories to indicate likely EG toxicity and guide treatment. A male presented by ambulance to hospital with severe agitation requiring mechanical ventilation to facilitate ongoing management. Venous blood gas analysis confirmed a high anion gap metabolic acidosis (HAGMA) with an elevated lactate. The lactate and osmolarity measured in the laboratory showed a normal lactate and high osmolarity, giving a large osmolar gap. The patient was immediately commenced on renal replacement therapy for presumed EG poisoning to minimize kidney injury, and the treatment continued for 19 hours. A very high EG concentration was confirmed by GC the next day. An elevated lactate gap along with a HAGMA and osmolar gap can provide rapid surrogate laboratory data indicating EG poisoning enabling timely treatment and better patient outcomes.

Study of Physiological Adaptations in Vertical Kilometer Runners: Focus on Cardiorespiratory and Local Muscle Demands.

Background: Research into key performance factors in trail running, particularly in vertical kilometer (VK) races, is crucial for effective training and periodization. However, recent studies on metabolic and cardiorespiratory responses during VK races, especially using field tests, are limited. Objectives: Therefore, the aim of this study is to evaluate the metabolic and cardiorespiratory responses during a VK field test, identifying differences based on sex and performance level, as well as key performance factors and their deterioration due to fatigue. Fifteen trained trail runners (ten males and five females, 19 to 38 years old) perform a VK race. Methods: The global physiological response is evaluated using the portable gas analyzer Cosmed K5 and the local response using near-infrared spectroscopy technology. Results: In gender comparisons, the ANCOVA test shows significant differences (p < 0.05) in the ventilation, tidal volume, expiratory time-to-inspiratory time ratio, inspiratory flow rate, end-tidal CO2 partial pressure, heart rate, oxygen pulse, and total hemoglobin. Additionally, the performance comparison reveals significant differences in the variables' velocity, oxygen consumption, carbon dioxide production, ventilation, dead space-to-tidal volume ratio, total time of the breathing cycle, expiratory time-to-inspiratory time ratio, inspiratory duty cycle, expiratory fractions of CO2, quadriceps saturation index, and VE/VCO2 ratio. Finally, the correlation analysis shows oxygen consumption (r = -0.80 mean; r = -0.72 peak), carbon dioxide production (r = -0.91 mean; r = -0.75 peak), expiratory time-to-inspiratory time ratio (r = 0.68 peak), ventilation (r = -0.58 mean), and quadriceps saturation index (r = 0.54 mean; r = -0.76 coefficient of variation) as the key performance factors in the VK race. Conclusions: Overall, the physiological analysis indicates the importance of local muscular adaptations and respiratory system capacity in this type of short-duration race.