Oxygenation Status Research Articles

Predictive Machine Learning Algorithms in Anticipating Problems with Airway Management

Machine learning is artificial intelligence (AI) which can predict the output variable with the fed input features. This allows computers to learn from experience without being programmed. The outcome variable in machine learning algorithm may be continuous variable or categorical variable. Supervised machine learning is commonly applied artificial intelligence (AI) in medical field. Decision tree, gradient boost machine (GBM) learning, extreme GBM (XGBM), Support vector machine, K nearest neighbour and multi-layer perceptron are few machine learning algorithms which are being utilised to address the classification and regression problems. Though the incidence of difficult intubation (DI) is rare, occurrence of such event in an unanticipated situation can result in development of arrhythmias due to desaturation and cardiac arrest if not intervened on time. It is preferred to choose the physical parameters that can predict the difficult airway more accurately in clinical scenario and train the algorithm rather than including all the non-specific parameters. Body mass index (BMI) [>30 kg.m-2: anticipated difficult mask ventilation (DMV), direct laryngoscopy (DL) and DI], inter-insicor distance (IID) (<2 cm: anticipated DL), modified Mallampati (MMP) (Grade 1 and 2: Ease of intubation; Grade 3 and 4: anticipated DI), temporomandibular distance (TMD) (<6.5 cm - anticipated DI), restriction of neck extension (if present: anticipated DL and DI), receded mandible (if present: anticipated DL and DI), and poor submandibular space compliance (if present: anticipated DL and DI) parameters which are used to predict DA by clinical assessment, can be used to feed to train the machine learning algorithm. Despite using these sophisticated tools, extubation may fail and patients require reintubation in ICU. It is very challenging to assess the lung compliance in spontaneously breathing patients as compliance will be overestimated due to generation of negative pressure. Cause for which patient has been placed on mechanical ventilation is resolved/resolving, BMI (>30 kg.m-2), intact sensorium (absence of delirium), absence of consolidation, absence of copious secretions, oxygenation status (PaO2/FiO2: >250), ventilation status (paCO2: 30-45 mmHg), measure of work of breathing (respiratory rate, rapid shallow breathing index), heart rate and blood pressure during spontaneous breathing trial (SBT) and diaphragmatic thickness fraction can be used as input features to predict the success of extubation in critically ill patients. With widespread utility of applications in medical fraternity, applications for prediction of difficult airway (or for weaning success) can be programmed which can be accessed by the clinicians to predict DA, thereby all the preparations for managing DA may be done to prevent adverse consequences of unanticipated difficult airway.

Systematic review and meta-analysis of mesenchymal stromal/stem cells as strategical means for the treatment of COVID-19.

In coronavirus disease 2019 (COVID-19) patients, elevated levels of inflammatory cytokines from over stimulation of immune cells have become a concern due to the potential outburst of cytokine storm that damages the tissues and organs, especially the lungs. This leads to the manifestation of COVID-19 symptoms, such as pneumonia, acute respiratory distress syndrome (ARDS), multiple organ failure, and eventually death. Mesenchymal stromal/stem cells (MSCs) are currently one of hopeful approaches in treating COVID-19 considering its anti-inflammatory and immunomodulatory functions. On that account, the number of clinical trials concerning the use of MSCs for COVID-19 has been increasing. However, the number of systematic reviews and meta-analysis that specifically discuss its potential as treatment for the disease is still lacking. Therefore, this review will assess the safety and efficacy of MSC administration in COVID-19 patients. To pool evidence on the safety and efficacy of MSCs in treating COVID-19 by observing MSC-related adverse effects as well as evaluating its effects in reducing inflammatory response and improving pulmonary function. Following literature search across six databases and one trial register, full-text retrieval, and screening against eligibility criteria, only eight studies were included for data extraction. All eight studies evaluated the use of umbilical cord-derived mesenchymal stromal/stem cell (UC-MSC), infused intravenously. Of these eight studies, six studies were included in meta-analysis on the incidence of mortality, adverse events (AEs), and serious adverse events (SAEs), and the levels of C-reactive protein (CRP) and interleukin (IL)-6. Meta-analysis on pulmonary function was not performed due to insufficient data. MSC-treated group showed significantly lower risk of mortality than the control group (p = 0.03). No statistical significance was observed on the incidence of AEs (p = 0.78) and SAEs (p = 0.44), and the levels of CRP (p = 0.06) and IL-6 (p = 0.09). MSCs were safe for use, with lower risk of mortality and no association with AEs. Regarding efficacy, descriptive analysis showed indications of improvement on the inflammatory reaction, lung clearance, and oxygenation status despite the lack of statistical significance in meta-analysis of CRP and IL-6. Nevertheless, more studies are needed for affirmation. This systematic review and meta-analysis was registered on the PROSPERO database (no. CRD42022307730).

Technical support for applying the method of normoxic therapeutic compression in narcological practice

The relevance of the development of technical systems for the treatment of alcohol withdrawal syndrome which allow to reduce the pharmacological load on the patient and increase the efficiency of the treatment process ensuring a reduction in economic costs is argued. Because hypoxia is one of the pathogenetic links of alcoholism the use of the normoxic therapeutic compression method in narcology for treatment both the main drug addiction disease and concomitant neurological and therapeutic diseases that patients with addiction to psychoactive substances suffer from is justified. The advantages of the normoxic therapeutic compression method compared to the hyperbaric oxygenation method are: safety, high therapeutic effect, absence of contraindications with the exception of claustrophobia, hypertensive crisis and diabetic coma. For the purpose of technical implementation of the normoxic therapeutic compression method a positive pressure oxygenation system was proposed. A distinctive feature of the developed system is that using appropriate sensors it measures the pulse and oxygen content in the patient’s bloodstream as well as the oxygen content and temperature inside the case. Based on the measurement results the system determines the patient’s oxygen status and controls the oxygen supply concentration and the temperature inside the case. In the process of testing the system it was found that the use of normoxic therapeutic compression in complex treatment is more effective compared with hyperbaric oxygenation in reducing the severity of pathological craving for alcohol mainly due to the vegetative component. The use of the proposed system makes it possible to optimize and improve the effectiveness of assistance in relieving pathological craving for alcohol during alcohol withdrawal syndrome as well as to reduce the time of patients’ stay in the hospital.

The Value of Non-invasive Electrocardiography in Assessing Fetal Status at Term Delivery.

The electrocardiograph (ECG) is efficient method for the accurate assessment of fetal heart rate. The barriers for accurate assessment are maternal heart rate, uterine contractions and abdominal muscles. Although previous monitoring methods have struggled to overcome these barriers, recent advances have led to a greater degree of success for listening and recording pulse-by-pulse fetal heart rate. A prospective cohort study evaluating the use, reliability and safety of non-invasive electrocardiography, in conjunction with Fetal Heart Rate parameters such as, Short Term Variability (STV) together with umbilical cord PH and Apgar score, during the active phase of childbirth. A total of 41 women with single, normal, full-term pregnancies had systematic obstetric monitoring with Monica AN24. 20 had only monitoring and 21 also had and arterial blood flow measurements. pH was measured and correlated with neonatal Apgar score at 1 and 5 min. The study also included a questionnaire about the safety and usability of obstetric monitoring. Statistical analysis was done using IBM SPSS v. 26.0. Mean age was 28.8 years, (SD ± 6.153). Electrocardiogram recordings (ECG) were classified as normal (71%) and suspicious (29%). Baseline between ECGs was different (p = 0.025) similarly for Short term variability (STV) (p <0.0001). BMI did not differentiate SVT rates. Only high acceleration (p <0.029) and small slowdowns had a statistically significant difference between normal and suspected cardiographs (p <0.029). APGAR score did not differ, whereas the umbilical cord pH was different in normal ECGs compared to the suspect (p = 0.012) and STV was also differentiated. A usability and safety survey was conducted after recording with MONIKA AN24, and the response to whether they would accept recording with the device again, was positive for 96% of the 30 responders. The present study shows that the use of electrocardiography in obstetrics allows to draw conclusions about the fetal hematopoiesis and oxygenation status. This method could be clinically applied and be an important tool for further screening in embryos that may be hypoxic and to decide whether to continue with a vaginal or cesarean delivery, thereby achieving the goal of reducing perinatal morbidity and mortality.

Enhancing anionic redox stability via oxygen coordination configurations.

Anionic redox in Li-rich cathode materials with disordered crystal structures has potential to increase battery energy density. However, capacity fading due to anionic redox-induced structural transformation hinders practical implementation. To address this challenge, it is crucial to understand the influence of the anion coordination structure on redox reversibility. By comprehensively studying the spinel-like Li1.7Mn1.6O3.7F0.3 and layered Li2MnO3 model systems, we found that tetrahedral oxygen exhibits higher kinetic and thermodynamic stability than octahedral oxygen in Li1.7Mn1.6O3.7F0.3 and Li2MnO3, effectively suppressing aggregation of oxidized anions. Electronic structure analysis showed that the 2p lone-pair states in tetrahedral oxygen lie deeper than those in octahedral oxygen. The Li-O-TM bond angle in a polyhedron is identified as a characteristic parameter to correlate anionic redox stability. TM substitutions using Co3+, Ti4+ and Mo5+ could effectively regulate the Li-O-Mn bond angle and anionic active electronic state. Our finding that anionic redox stability is influenced by the polyhedral structure offers new opportunities for designing high-energy-density Li-rich cathode materials.

The use of photodynamic therapy in the complex treatment of chronic generalized moderate periodontitis

Improving the effectiveness of the treatment of chronic generalized periodontitis by photodynamic therapy (PDT) due to clinical and functional validation of the effects of a photosensitizer. A clinical and functional study and treatment of moderate chronic generalized periodontitis was carried out in 60 people (24 males and 36 females) aged 35 to 50 years without somatic pathology with orthognathic bite. The patients were divided into 2 groups depending on the type of treatment: group 1 (main) included 30 patients (17 males and 13 females, mean age of patients was 42.5±3.3 years) who received comprehensive treatment consisting of oral sanitation, removal of dental plaque and curettage of periodontal pockets followed by PDT with 1% Geleophor gel using an AFS Spektr LED emitter with a wavelength of 660 nm and a power of 2.5 W, the course consisted of 4 procedures with exposure time of 7 minutes each; group 2 (control) included 30 patients (11 males and 19 females, mean age of patients was 43.0±2.1 years) undergoing standard treatment followed by protective capping with no active therapeutic agent. The state of microcirculation in tissues was studied by the laser Doppler flowmetry (LDF) using the LAKK-M device (Lazma, Russia). According to LDF data in both groups, it was found that the improvement of microcirculation in periodontal tissues after complex treatment is accompanied by an increase in blood flow and its activity, at that the level of oxygenation and specific oxygen consumption increased more pronounced after PDT, the effect persisted after 6 and 12 months. The use of PDT with LED emitter has a normalizing effect on the state of microcirculation and oxygenation in periodontal tissues.

The Electronic Kinetics of Molecular Nitrogen and Molecular Oxygen in the Earth’s Middle Atmosphere during the GLE Events of Solar Cycle 23

Based on models of the electronic kinetics of triplet and singlet states of molecular nitrogen andsinglet states of molecular oxygen for the Earth’s middle atmosphere, we calculated the intensity profiles ofthe bands of the first and second positive N2 systems, the Lyman–Birge–Hopfield N2 bands, and the infraredO2 bands in the case of precipitation of high-energy protons during the GLE65, GLE67, GLE69, and GLE70events of solar cycle 23. Calculations have shown that almost over the entire interval of altitudes of 20–80 km,there is a significant contribution from the processes of quenching some electronically excited states of N2and O2 during molecular collisions. The kinetics of O2 singlet states at the altitudes of the middle atmosphereduring proton precipitation is considered taking into account both direct excitation by high-energy particlesand intermolecular processes of electron excitation transfer

Room temperature epoxidation of ethylene over delafossite-based AgNiO2 nanoparticles.

A mixed oxide of silver and nickel AgNiO2 was obtained via co-precipitation in alkaline medium. This oxide demonstrates room temperature activity in the reaction of ethylene epoxidation with a high selectivity (up to 70%). Using the PDF method, it was found that the initial structure of AgNiO2 contains stacking faults and silver vacancies, which cause the nonstoichiometry of the oxide (Ag/Ni < 1). It has been established that on the initial surface of AgNiO2 oxide, silver state can be considered as an intermediate between Ag2O and Ag0 (i.e. Agδ+-like), while nickel is characterized by signs of a deeply oxidized state (Ni3+-like). The interaction of AgNiO2 with C2H4 at room temperature leads to the simultaneous removal of two oxygen species with Eb(O 1s) = 529.0 eV and 530.5 eV considered as nucleophilic and electrophilic oxygen states, respectively. Nucleophilic oxygen was attributed to the lattice oxygen (Ag-O-Ni), while the electrophilic species with epoxidation activity was associated with the weakly bound oxygen stabilized on the surface. According to the TPR-C2H4 data, a large number of weakly bound oxygen species were found on the pristine AgNiO2 surface. The removal of such species at room temperature didn't result in noticeable structural transformation of delafossite. As the temperature of ethylene oxidation over AgNiO2 increased, the appearance of Ag0 particles was first observed below 200 °C followed by the complete destruction of the delafossite structure at higher temperatures.

The Intervention of Trunk Posture on Fowler 30o to Reduce Shortness of Breath in Congestive Heart Failure Patients : Case Study

Shortness of breath in patients with congestive heart failure is caused by impaired lung function due to pulmonary. One of the efforts that can be made to overcome shortness of breath and improve oxygenation status is to change the position of the trunk posture in fowler 30o. This case study was conducted to analyze the application of the 30o trunk posture in the fowler position in patients with congestive heart failure who experience shortness of breath. The research used a case study of patients with congestive heart failure who experience shortness of breath. After giving a 30o trunk posture in the fowler position for three days of treatment, there was a change of blood pressure, pulse rate, respiration, and oxygen saturation of the patient. The position of the trunk in fowler posture 30o can reduce shortness of breath in patients with congestive heart failure.

Impact of ozonation on the optical properties and photo-reactivity of dissolved organic matter

With the increasing amount of wastewater discharges, the subsequent influence of treated effluent on the photochemistry of natural receiving waters has become more significant. Recently, the effect of treatment operations on the photo-reactivity of dissolved organic matter (DOM) has gained much attention. Meanwhile, some well-established correlations between spectroscopic measurements and photochemical behaviors become unreliable in treated DOM, thus requiring more robust relationships for better prediction. In the present research, the variations of optical and photochemical properties of DOM after ozonation were investigated. The correlations between fluorescence and reactive species photo-production were further explored through parallel factor analysis (PARAFAC). Results showed that ozonation induced the decline of aromaticity, molecular weight, and fluorescence intensities for all samples, which led to reduced photo-production of excited triplet states of DOM (3DOM*) and singlet oxygen (1O2). By contrast, the photo-formation of hydroxyl radical (•OH) was promoted. The correlations between optical parameters and quantum yields were evaluated. Furthermore, the max fluorescence intensity of PARAFAC components was used in linear regression modeling to predict the formation rate of 1O2 and •OH (R1O2 and R•OH). The contribution of each part was calculated. The good fit of R1O2 implied that ozonation would not affect the potential intrinsic relation between fluorophores and 1O2-producing chromophores. In contrast, the unsatisfactory modeling results of R•OH indicated a weak correlation between fluorescence and •OH formation. These findings suggest that ozonation influences the photo-reactivity of DOM and hint at the possibility of applying fluorescence combined with PARAFAC to explore 1O2 formation quantitatively.

Unveiling the High-valence Oxygen Degradation Across the Delithiated Cathode Surface.

Charge compensation on anionic redox reaction (ARR) has been promising to realize extra capacity beyond transition metal redox in battery cathodes. The practical development of ARR capacity has been hindered by high-valence oxygen instability, particularly at cathode surfaces. However, the direct probe of surface oxygen behavior has been challenging. Here, the electronic states of surface oxygen are investigated by combining mapping of resonant Auger electronic spectroscopy (mRAS) and ambient pressure X-ray photoelectron spectroscopy (APXPS) on a model LiCoO2 cathode. The mRAS verified that no high-valence oxygen can sustain at cathode surfaces, while APXPS proves that cathode electrolyte interphase (CEI) layer evolves and oxidizes upon oxygen gas contact. This work provides valuable insights into the high-valence oxygen degradation mode across the interface. Oxygen stabilization from surface architecture is proven a prerequisite to the practical development of ARR active cathodes.

Unveiling the High‐valence Oxygen Degradation Across the Delithiated Cathode Surface

AbstractCharge compensation on anionic redox reaction (ARR) has been promising to realize extra capacity beyond transition metal redox in battery cathodes. The practical development of ARR capacity has been hindered by high‐valence oxygen instability, particularly at cathode surfaces. However, the direct probe of surface oxygen behavior has been challenging. Here, the electronic states of surface oxygen are investigated by combining mapping of resonant Auger electronic spectroscopy (mRAS) and ambient pressure X‐ray photoelectron spectroscopy (APXPS) on a model LiCoO2 cathode. The mRAS verified that no high‐valence oxygen can sustain at cathode surfaces, while APXPS proves that cathode electrolyte interphase (CEI) layer evolves and oxidizes upon oxygen gas contact. This work provides valuable insights into the high‐valence oxygen degradation mode across the interface. Oxygen stabilization from surface architecture is proven a prerequisite to the practical development of ARR active cathodes.

Measurement and simulation of temperature-dependent spontaneous Raman scattering of O2 including P and R branches

Evaluation methods for species and temperature determination in gaseous mixtures using spontaneous Raman scattering require detailed information on the spectra of the involved species. For most diatomic and some triatomic molecules that are relevant in combustion processes (H2, N2, O2, CO, CO2, H2O) these spectra can be simulated based on the underlying quantum mechanical processes. In contrast to the other diatomic molecules, the electronic ground state of oxygen has an electronic spin of S=1 which leads to the tripling of transitions and the occurrence of P and R branches. Though being neglected so far due to their small effect size, these additional transitions change the spectral shape and the integrated signal intensity which can lead to inaccuracies in evaluation methods such as the hybrid matrix inversion or full spectral fit. In this paper, P and R branches were simulated and their effect on the ro-vibrational oxygen spectrum evaluated by comparison to high-resolution experimental spectra in temperatures up to over 2000 K. Spectral fitting of O2 using this simulation allows for temperature determination of gaseous mixtures with a uncertainty better than 10 K and no significant difference to temperatures determined with the more established fitting of N2. Fitted temperatures deviate by 4 K or less when P and R transitions are considered but fitting quality improves significantly when including them in the simulation. More importantly, neglecting P and R transitions leads to an overestimation of the temperature-dependent Raman cross section of O2 which causes underestimations of O2 concentration measurements using the hybrid matrix inversion or full spectral fit method.

Highly Selective Gas Sensor Based on Litchi-like g-C3N4/In2O3 for Rapid Detection of H2.

Hydrogen (H2) has gradually become a substitute for traditional energy, but its potential danger cannot be ignored. In this study, litchi-like g-C3N4/In2O3 composites were synthesized by a hydrothermal method and used to develop H2 sensors. The morphology characteristics and chemical composition of the samples were characterized to analyze the gas-sensing properties. Meanwhile, a series of sensors were tested to evaluate the gas-sensing performance. Among these sensors, the sensor based on the 3 wt% g-C3N4/In2O3 (the mass ratio of g-C3N4 to In2O3 is 3:100) showeds good response properties to H2, exhibiting fast response/recovery time and excellent selectivity to H2. The improvement in the gas-sensing performance may be related to the special morphology, the oxygen state and the g-C3N4/In2O3 heterojunction. To sum up, a sensor based on 3 wt% g-C3N4/In2O3 exhibits preeminent performance for H2 with high sensitivity, fast response, and excellent selectivity.

Possible source of Au in the Jiaodong area from lower crustal sulfide cumulates: Evidence from oxygen states and chalcophile elements contents of Mesozoic magmatic suites

The genesis of giant Jiaodong gold province remains perplexing although many ore-forming models have been proposed in the past decades. The key issues are what caused the burst of gold around 120 Ma and possible sources of gold. Here we report gold and platinum group elements (PGE) data and magmatic oxidation states of the pre-mineralization Mesozoic plutonic rocks and some mafic dykes to discuss their potential effects on gold mineralization. Gold concentrations of the Late Jurassic Linglong granite are 0.015–0.278 ppb. The Early Cretaceous plutonic rocks (129–127 Ma) have the same levels of Au concentrations (Au = 0.031–0.047 ppb). Both of the Jurassic and Cretaceous magmatic rocks are depleted in Au compared to normal granitic rocks worldwide (∼1 ppb). Palladium and platinum concentrations in the Linglong granite are 0.160–0.385 ppb and 0.046–0.116 ppb, respectively. Meanwhile, Pd and Pt contents of Cretaceous magmatic rocks are 0.069–0.363 ppb and 0.063–0.465 ppb, respectively.Oxygen fugacities of the Late Jurassic Linglong granite calculated by biotite oxybarometer are FMQ + 0.5 to FMQ + 1.2 (where FMQ refers to fayalite-magnetite-quartz buffer). Oxidation states of the Early Cretaceous magmatic rocks estimated via amphibole oxybarometer are from FMQ + 0.3 to FMQ + 1.1 for Guojialing granodiorite. Zircon trace element data yield overall higher fO2 values than those estimated with biotite and amphibole compositions. Oxygen fugacities are from FMQ – 0.6 to FMQ + 1.9 (sample CJ-3) and FMQ – 0.7 to FMQ + 1.1 (sample LL-1) for the two Linglong granite samples. Zircons from the Early Cretaceous Guojialing pluton yield oxidation states between FMQ – 0.8 and FMQ + 1.9 (DCW-1), which are about one log unit higher than those of the Beijie pluton (BJ-1: FMQ – 1.0 to FMQ + 0.7). However, oxidation states from nearly syn-mineralization mafic dyke reach FMQ + 2.0 to + 3.0 when estimated via zircon oxybarometer. Oxidation states given by whole rock Fe3+/Fe2+ ratios also support the results calculated by mineral compositions.There is no fractionation crystallization of redox-sensitive minerals, like magnetite or garnet, as indicated by geochemical data, which implies that the oxidation states of magmas may reflect their source regions. However, the depleted nature of Au and PGE must imply that these elements are missing. We propose that sulfide saturation at the deep crust can be invoked to explain the extremely low gold and PGE contents of these magmatic rocks. The sulfide cumulates act as sinks for sulfide-loving elements (e.g., Au), which are pre-enriched source for later large-scale gold mineralization in Jiaodong area. The underplated water-rich mafic magma from enriched mantle source ponded at the lower crust, continuously crystallized anhydrous minerals (e.g., olivine and clinopyroxene) and reached volatile saturation at the very moment. This volatile, probably carrying gold, resorbed the sulfide cumulate and escaped to shallow levels to form the giant Jiaodong gold deposits.

Serum calprotectin can indicate current and future severity of COVID-19.

Predictive and prognostic biomarkers to guide 2019 novel coronavirus disease (COVID-19) are critically evolving. Dysregulated immune responses are the pivotal cause of severity mainly mediated by neutrophil activation. Thus, we evaluated the association of calprotectin, neutrophil secretory protein, and other mediators of inflammation with the severity and outcomes of COVID-19. This two-center prospective study focused on PCR-proven COVID-19 patients (n= 76) with different clinical presentations and SARS-CoV-2 negative control subjects (n= 24). Serum calprotectin (SC) was compared with IL-6 and other laboratory parameters. Median levels of SC were significantly higher in COVID-19 patients in comparison to the control group (3760 vs. 2100 ng/ml, p< 0.0001). Elevated SC was significantly respective of disease severity (3760 ng/ml in mild up to 5700 ng/ml in severe cases, p< 0.0001). Moreover, the significant positive and negative correlations of SC with disease severity and oxygenation status indicated disease progression and respiratory worsening, respectively. It was found that SC was high in severe patients during hospitalization and significantly declined to normal after recovery. The logistic analysis identified the independent predictive power of SC for respiratory status or clinical severity. Indeed, SC behaved as a better discriminator for both outcomes, as it exhibited the largest area under the curve (receiver operating curve analysis), with the highest specificity and sensitivity when the predictive value of inflammatory biomarkers was compared. Calprotectin can be used as a reliable prognostic tool to predict the poor clinical outcomes of COVID-19 patients.

Exploration for oxygen diffusion during deoxidation process of terbium with 18O as isotope tracer

Oxygen (O) is the most difficult kind of impurity to be removed from rare earth terbium (Tb), which seriously restricts the promotion of high purity rare earth metal quality. Study the law of oxygen removal during the purification process and clarify the influence and synergism of active substance are of great significance. Herein, isotopic tracer technique (using 18O) has been used to explore the oxygen diffusion process. Secondary ion probe mass spectrometer (SIMS) and Scanning Electron Microscope (SEM) investigated the occurrence state, migration trajectory and relative concentration gradient of oxygen in Tb. The diffusion coefficient as a function of depth and temperature can be simulated based on the experimental data, which is of great significance for the purification and corrosion prevention of Tb. X-ray photoelectron spectroscopy (XPS) clarified the variation of metal valence, indicating the bonding characteristics between O and Tb.

The value of magnetic resonance blood oxygen level-dependent imaging in evaluating the efficacy of advanced cervical cancer combined with radiotherapy and chemotherapy.

Blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) is an imaging method used to analyze oxygenation status of the tumor. To investigate the feasibility of BOLD-MRI in evaluating the efficacy of advanced cervical cancer combined with radiotherapy and chemotherapy. This prospective study included 85 patients with advanced cervical cancer who received BOLD-MRI examination before and after concurrent chemoradiotherapy from October 2020 to December 2021. To investigate the changes of baseline R2* values and △R2* values of cervical cancers before and after treatment. 29 cases were complete response, 34 cases were partial response, and 22 cases showed progression. The baseline R2* values of the tumors were lower than that of the normal cervical muscle (P < 0.0001). After oxygen stimulation, the baseline R2* values of the tumors decreased (P = 0.012). After treatment, the baseline R2* values of the tumors increased (P = 0.007), and the dynamic △R2* values of the tumors decreased (P = 0.025). The baseline R2* value of the complete response was the highest (P = 0.000), the dynamic △R2* value of the complete response was the lowest (P = 0.017). BOLD-MRI can evaluate the efficacy of concurrent chemoradiotherapy for advanced cervical cancer.

Initial oxygenation as early predictor of mortality in acute respiratory distress syndrome: a retrospective study

Introduction: Acute respiratory distress syndrome (ARDS) is a major contributor to mortality and morbidity of adult patients admitted to intensive care units (ICU). Numerous scoring systems have been developed for critically ill patients with the goal of more accurately predicting clinical outcomes. However, the variability in these scores among individual patients, and consequently, their individual predictive ability is quite limited. Aim: To evaluate the role of initial oxygenation as an early predictor of mortality in ARDS patients. Methodology: One hundred and six mechanically ventilated adult patients with ARDS were enrolled retrospectively. Baseline parameters from the day of ICU admission were recorded. The details of ventilation, inspired oxygen fraction required, positive end-expiratory pressure and number of days on ventilation along with duration of hospital stay were recorded. Similarly, the status of oxygenation was assessed using PaO2/FiO2 (P/F) ratio. Survival of the patients was correlated with the baseline status of oxygenation. Results: Of the 106 patients, 65 were males and 41 female. The mean (± SD) age was 44 years (16.08). The difference in the P/F ratio between survivors and nonsurvivors was statistically significant. The ROC curve showed a cutoff value for P/F ratio of 108. Among survivors, the ICU stay was shorter in patients in pulmonary group compared to extrapulmonary group. Conclusion: Mortality is high if the baseline P/F ratio at admission is below 108. There is no difference in mortality due to lung injury caused by pulmonary or extrapulmonary aetiologies. ICU stay is longer among survivors if cause of ARDS is extrapulmonary.

On-chip spectroscopic monitoring of erythrocyte oxygenation under hematocrit and oxygen gradients

The interpretation of the variability and determinants of erythrocyte oxygenation is complicated by multiple interacting factors manifesting gaseous and fluidic microenvironments during microcirculation. In this paper, a multifunctional microdevice was developed for quantitatively extracting the dominant role of RBC concentration, local oxygen (O 2 ), and fluid dynamics in an ex vivo setting. Serial dilution of RBCs was achieved by repeated splitting and mixing of the source RBC suspension solutions in the bifurcating serpentine microchannels. O 2 perfusion of buried microchannels in a gas-permeable polydimethylsiloxane membrane allowed for exposing RBCs to a spatial linear O 2 gradient along with the blood flow direction. Taking the variability in the optically relevant properties of erythrocytes and their oxygenation status, an optical-fiber-based measurement system was integrated with the microfluidic device to capture the characteristic spectroscopic features of RBCs covering the visible to near-infrared range. The spectroscopic analysis provided a linear regression model of oxygen saturation with variables containing RBC concentrations, O 2 levels, and blood flow velocity, which agreed well with numerical simulation results. This systematic experimental approach could be applicable as an in vitro microcirculatory model system while adding a dimension to a wide range of blood processing and analysis. • A microfluidic device was developed for rendering serial RBC and O 2 gradients. • The vis-NIR spectra of RBCs were captured by an on-chip optical-fiber system. • The RBC oxygenation was studied with multiple variables and increased throughput. • Numerical simulation and vis-NIR spectra analysis showed a consistent StO 2 profile.