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Establishing the presence and state of organic matter, including its possible biosignatures, in martian materials has been an elusive quest, despite limited reports of the existence of organic matter on Mars. We report the in situ detection of organic matter preserved in lacustrine mudstones at the base of the ~3.5-billion-year-old Murray formation at Pahrump Hills, Gale crater, by the Sample Analysis at Mars instrument suite onboard the Curiosity rover. Diverse pyrolysis products, including thiophenic, aromatic, and aliphatic compounds released at high temperatures (500° to 820°C), were directly detected by evolved gas analysis. Thiophenes were also observed by gas chromatography–mass spectrometry. Their presence suggests that sulfurization aided organic matter preservation. At least 50 nanomoles of organic carbon persists, probably as macromolecules containing 5% carbon as organic sulfur molecules.

To investigate the effect of prolonged time before analysis and mechanical manipulation on pre-analytical stability of biomarkers and the validity of blood gas analysis results. We collected blood samples from 240 ICU patients from May 18, 2022 to March 31, 2023. Samples were analyzed immediately per standard operating procedure, then the syringes were kept at room temperature for 60 min, subjected to standardized mechanical forces (repeated drops) and analyzed again. Thirteen typical blood gas analytes were measured. Bland-Altman plots were prepared to assess differences between initial and delayed analyses. Differences were compared against official accuracy limits specified in German quality assurance guidelines (Rili-BAEK). For hemoglobin, creatinine, glucose, and electrolytes (calcium, sodium, chloride, bicarbonate), agreement between immediate and post-delay analyses remained within the official acceptable ranges. For pH and potassium, deviations exceeded the Rili-BAEK accuracy limits but remained clinically acceptable. Only oxygen partial pressure and lactate levels changed so markedly that they would no longer be reliable for clinical interpretation. Even after a 60-min delay and excessive mechanical stress, selected blood gas analytes such as hemoglobin, glucose, and electrolytes can be considered valid. Potassium and carbon dioxide partial pressure were altered but might be suitable for approximation purposes. Findings for oxygen partial pressure and lactate were generally invalid. In the future, these findings can aid in reducing unnecessary blood sampling. These findings may guide clinicians in deciding whether repeat sampling is necessary, potentially reducing unnecessary blood draws, while reinforcing that critical parameter (pO₂, pCO₂, pH) still require prompt analysis.

ABSTRACT Background Point‐of‐care testing of blood gases plays a critical role in patient management. The aim of this study was to verify the manufacturer's specifications of the Nova Stat Profile Prime Plus Analyser, along with a comparison study with the GEM Premier 4000 Blood Gas Analyser. Methods Parameters analysed were pH, pCO2, pO2, Na+, Cl−, K+, iCa, lactate, and glucose. Data for the precision and bias study were generated using control samples in a 5 × 5 study design. Linearity was checked using a five‐level Linearity Control Set, while comparison was done between the Nova and GEM analysers using whole blood samples (N = 103). Acceptance was based on the CLIA TEa for all analytes except for lactate, for which the TEa defined by CAP and AAB was used. Results The within‐run and between‐run CVR% precision were all lower than the claimed CVs%, except for pCO2 control level 2 within run (CV% 1.5 [claim CV% 1.1]) and iCa control level 5 between run (CV% 1.42 [claim 1.12]). The observed bias for all parameters was within the calculated lower and upper bias limits. Linearity was verified for all analytes except for Na+. Upon comparison of the Nova and GEM analysers, a correlation coefficient above 0.95 was observed for most parameters. Conclusion The Nova Stat Profile Prime Plus analyser meets the manufacturer's precision and bias claims. Linearity was confirmed for most analytes. There was a good correlation between the Nova and GEM Blood Gas analyser at concentrations within the reference range intervals for all investigated parameters. Point‐of‐care (POC) testing of blood gases plays a critical role in the management of patients both in the emergency department and in a critical care setting. Findings from this study confirm that the Nova Stat Profile Prime Plus analyser meets the manufacturer's precision and bias claims. Linearity was confirmed for pCO2, pO2, K+, Cl‐ and iCa. A good correlation was found between the Nova Stat Profile Prime Plus and GEM Premier Blood Gas analysers at concentrations within the reference range intervals for all the investigated parameters.

Portable blood gas analyzers are used to facilitate diagnosis and treatment of disorders related to disturbances of acid-base and electrolyte balance in the ambulatory care of equine patients. The aim of this study was to determine whether 2 portable analyzers produce results in agreement with a stationary analyzer. Blood samples from 23 horses hospitalized for various medical reasons were included in this prospective study. Blood gas analysis and electrolyte concentrations measured by the portable analyzers VetStat and epoc were compared to those produced by the cobas b 123 analyzer via concordance analysis, Passing-Bablok regression and Bland-Altman analysis. Limits of agreement indicated relevant bias between the VetStat and cobas b 123 for partial pressure of oxygen (pO2; 27.5-33.8 mmHg), sodium ([Na+]; 4.3-21.6 mmol/L) and chloride concentration ([Cl-]; 0.3-7.9 mmol/L) and between the epoc and cobas b 123 for pH (0.070-0.022), partial pressure of carbon dioxide (pCO2; 3.6-7.3 mmHg), pO2 (36.2-32.7 mmHg) and [Na+] (0.38.1 mmol/L). The VetStat analyzer yielded results that were in agreement with the cobas b 123 analyzer for determination of pH, pCO2, bicarbonate ([HCO3-]) and potassium concentration [K+], while the epoc analyzer achieved acceptable agreement for [HCO3-] and [K+]. The VetStat analyzer may be useful in performing blood gas analysis in equine samples but analysis of [Na+], [Cl-] and pO2 should be interpreted with caution. The epoc delivered reliable results for [HCO3-] and [K+], while results for pH, pCO2, pO2 and [Na+] should be interpreted with caution.

Background Continuous blood gas monitoring (CBGM) during cardiopulmonary bypass (CPB) is essential for maintaining optimal patient outcomes, enabling rapid responses to critical fluctuations in blood gas parameters. This non-inferiority study evaluates the Quantum Perfusion System by Spectrum Medical, which features continuous online blood gas monitoring through Quantum workstation (QWS) and Quantum ventilation module (QVM) without the use of cuvettes, against the standard blood gas analysis (BGA) analyzer to assess real-time clinical accuracy. Methods This retrospective study included a sample of 40 patients, monitored continuously with the QPS and compared at intervals against standard BGA measurements. The patients undergoing on elective CPB procedures, specifically for coronary artery bypass grafting (CABG), mitral valve replacement (MVR), and aortic valve replacement (AVR). Results Pre-alignment deviations for all parameters were within CLIA thresholds, confirming baseline reliability. For hemoglobin, the pre-alignment deviation was 1.9%, which decreased to 0.7% post-alignment, both within the CLIA threshold of ± 5%, with a Bland-Altman mean difference of 0.0988 g/dL (limits: 0.0963 to 0.1012 g/dL). Hematocrit showed a pre-alignment deviation of 2.1%, reduced to 0.2% post-alignment, both within the CLIA threshold of ± 5%, with a Bland-Altman mean difference of 0.3009% (limits: 0.2956 to 0.3063%). For PaO₂, the pre-alignment deviation was 3.9%, reduced to 0.4% post-alignment, both within the CLIA threshold of ± 10%, with a Bland-Altman mean difference of 4.0490 mmHg (limits: 3.9976 to 4.1004 mmHg). PCO₂ demonstrated a pre-alignment deviation of 4.2%, reduced to 0.19% post-alignment, both within the CLIA threshold of ± 10%, with a Bland-Altman mean difference of 0.3790 mmHg (limits: 0.3751 to 0.3829 mmHg). SvO₂ showed a pre-alignment deviation of 3%, which decreased to 0.8% post-alignment, both within the CLIA threshold of ± 5%, with a Bland-Altman mean difference of 0.7782% (limits: 0.7706 to 0.7858%). Finally, for SaO₂, the pre-alignment deviation was 2.6%, reduced to 0.1% post-alignment, both within the CLIA threshold of ± 5%, with a Bland-Altman mean difference of 0.9614% (limits: 0.9594 to 0.9634%). The Passing-Bablok regression analysis confirmed strong agreement, with slopes close to 1.0100 and intercepts near zero for all parameters. These results validate the QPS as a reliable and non-inferior tool for real-time blood gas monitoring during cardiopulmonary bypass, adhering to CLIA standards and ensuring clinical accuracy. Conclusions The findings support the accuracy of the Quantum Perfusion System compared to the BGA standard, demonstrating the system’s capability to provide accurate, continuous blood gas monitoring during CPB. However, further studies are necessary to strengthen and confirm these results across broader and more varied clinical scenarios, for these reason as recommended by the manufacturers, the quantum monitoring system should only be used as a trending device.

Elevated D-dimer is known as predictor for severity of SARS-CoV2-infection. Increased D-dimer is associated with thromboembolic complications, but it is also a direct consequence of the acute lung injury seen in COVID-19 pneumonia. To evaluate the rate of persistent elevated D-dimer and its association with thromboembolic complications and persistent ground glass opacities (GGO) after recovery from COVID-19. In this post hoc analysis of a prospective multicenter trial, patients underwent blood sampling, measurement of diffusion capacity, blood gas analysis, and multidetector computed tomography (MDCT) scan following COVID-19. In case of increased D-dimer (>0,5 [mu]g/ml), an additional contrast medium-enhanced CT was performed in absence of contraindications. Results were compared between patients with persistent D-dimer elevation and patients with normal D-dimer level. 129 patients (median age 48.8 years; range 19-91 years) underwent D-Dimer assessment after a median (IQR) of 94 days (64-130) following COVID-19. D-dimer elevation was found in 15% (19/129) and was significantly more common in patients who had experienced a severe SARS-CoV2 infection that had required hospitalisation compared to patients with mild disease (p = 0.049). Contrast-medium CT (n = 15) revealed an acute pulmonary embolism in one patient and CTEPH in another patient. A significant lower mean pO2 (p = 0.015) and AaDO2 (p = 0.043) were observed in patients with persistent D-Dimer elevation, but the rate of GGO were similar in both patient groups (p = 0.33). In 15% of the patients recovered from COVID-19, persistent D-dimer elevation was observed after a median of 3 months following COVID-19. These patients had experienced a more severe COVID and still presented more frequently a lower mean pO2 and AaDO2.

This book is a comprehensive guide that includes information on the origin and analysis of natural gas, the standard test methods, and procedures that help with the predictability of gas composition and behavior during gas cleaning operations and use. The author-a noted expert on the topic-also explores the properties and behavior of the various components of natural gas and gas condensate. All chapters are written as stand-alone chapters and they cover a wealth of topics including history and uses; origin and production; composition and properties; recovery, storage, and transportation; properties and analysis of gas stream and gas condensate. The text is designed to help with the identification of quality criteria appropriate analysis and testing that fall under the umbrella of ASTM International. ASTM is an organization that is recognized globally across borders, disciplines and industries and works to improve performance in manufacturing and materials and products.

Coronavirus disease-2019 (COVID-19) has made the world more cautious about widespread viruses, and a tragic pandemic that was caused by a novel coronavirus has harmed human beings in recent years. The new coronavirus pneumonia outbreak is spreading rapidly worldwide. We collect arterial blood samples from 51 patients with a COVID-19 diagnosis. Blood gas analysis is performed using a Siemens RAPID Point 500 blood gas analyzer. To accurately determine the factors that play a decisive role in the early recognition and discrimination of COVID-19 severity, a prediction framework that is based on an improved binary Harris hawk optimization (HHO) algorithm in combination with a kernel extreme learning machine is proposed in this paper. This method uses specular reflection learning to improve the original HHO algorithm and is referred to as HHOSRL. The experimental results show that the selected indicators, such as age, partial pressure of oxygen, oxygen saturation, sodium ion concentration, and lactic acid, are essential for the early accurate assessment of COVID-19 severity by the proposed feature selection method. The simulation results show that the established methodlogy can achieve promising performance. We believe that our proposed model provides an effective strategy for accurate early assessment of COVID-19 and distinguishing disease severity. The codes of HHO will be updated in https://aliasgharheidari.com/HHO.html. •In this paper, specular reflection learning is combined with HHO for the first time.•An improved Harris hawk optimization (HHOSRL) is proposed to feature selection.•HHOSRL has higher classification accuracy and smaller number of features in feature selection.•HHOSRL performs well on a variety of different machine learning classifiers.

Different from the Qaidam basin with about 320 billion m 3 microbial gas, only limited microbial gases were found from the Junggar basin with similarly abundant type III kerogen. To determine whether microbial gases have not yet identified, natural gas samples from the Carboniferous to Cretaceous in the Junggar basin have been analyzed for chemical and stable isotope compositions. The results reveal some of the gases from the Mahu sag, Zhongguai, Luliang and Wu-Xia areas in the basin may have mixed with microbial gas leading to straight ethane to butane trends with a “dogleg” light methane in the Chung’s plot. Primary microbial gas from degradation of immature sedimentary organic matter is found to occur in the Mahu sag and secondary microbial gas from biodegradation of oils and propane occurred in the Zhongguai, Luliang and Beisantai areas where the associated oils were biodegraded to produce calcites with δ 13 C values from + 22.10‰ to + 22.16‰ or propane was biodegraded leading to its 13 C enrichment. Microbial CH 4 in the Mahu sag is most likely to have migrated up from the Lower Wuerhe Formation coal-bearing strata by the end of the Triassic, and secondary microbial gas in Zhongguai and Beisantan uplifts may have generated after the reservoirs were uplifted during the period of the Middle and Late Jurassic. This study suggests widespread distribution of microbial gas and shows the potential to find large microbial gas accumulation in the basin.