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In this work, we investigated the effects of interfacial oxygen vacancies on the ferroelectric behaviors and switching properties of Al:Hf0.5Zr0.5O2 (Al:HZO) films. Our study employed a Pt/Al:Hf0.5Zr0.5O2/Si structure to form two interfaces with different interfacial oxygen defects. Oxygen vacancies were mainly accumulated at the HZO/Si interface, confirmed by the XPS results. By carefully examining the P–V loops, C–V loops, and the corresponding switching current loops, we found that the domains were clearly divided into two parts, which resulted in the slit-up of the switching current peaks and distorted P–V loops. Further cycling results showed that the wake-up performances had arisen from the biased domains. We further simulated the switching dynamics by using the nucleation limited switching model. Distorted switching kinetics and unsatisfied switching polarization were observed for the initial samples, while the switching dynamics showed the same tendency after waking up. The results elucidate that the influence of interfacial oxygen vacancies is mainly to induce the built-in field at the interface, which may be helpful for the understanding of the switching behaviors of HfO2-based ferroelectric films. [ABSTRACT FROM AUTHOR]

We describe the impact of post-annealing on ferroelectric-domain structures in arrays of BiFeO3 (BFO) epitaxial nanoislands, which exhibit a domain evolution from an initial 71° stripe/vortex domains to center-convergent topological domains. These results suggest that the increase and redistribution of charged defects, e.g., oxygen vacancies, in BFO nanoislands play a crucial role in driving the formation of center-type domain structures. The observation of defect-driven domain evolution in BFO nanoislands provides a path for further exploring their formation mechanism, topological properties, novel functionalities, and potential applications. [ABSTRACT FROM AUTHOR]

We present a detailed study on the effects of oxygen on the photoluminescence properties of CdSe/CdS quantum dots (QDs). We investigated the role of oxygen by performing confocal measurements on thin films as well as on single particles while rapidly exchanging the gaseous environment between oxygen and an inert gas atmosphere. We found that the deionization of negatively charged particles by oxygen depends on both the excitation power and the shell thickness of the QDs. For QDs with thin shells, which exhibit strong photoluminescence blinking, we observed that the presence of oxygen affects both band-edge carrier blinking and hot-carrier blinking. [ABSTRACT FROM AUTHOR]

To tackle the challenge of ground-level ozone pollution, this study proposed a potential catalytic design approach for ozone decomposition using Cu–Mn bimetallic oxide. This approach is grounded in an understanding of the intrinsic reactivity for catalyst and incorporates a novel potassium-driven low-temperature oxidation process for catalyst synthesis. The research highlights the creation of a highly reactive Cu–Mn oxide phase with extensive defect coverage, leading to significantly increased reaction rates. It also identifies the MnO2(100) facet as a crucial active phase, where oxygen vacancies simultaneously enhance O3 adsorption and decomposition, albeit with a concurrent risk of O2 poisoning due to the stabilization of adsorbed O2. Crucially, the incorporation of Cu offsets the effects of oxygen vacancies, influencing conversion rates and lessening O2 poisoning. The synergistic interplay between Cu and oxygen vacancies elevates the performance of the defect-rich Cu–Mn oxide catalyst. By combining computational and experimental methods, this study not only advances the understanding of the Cu–Mn oxide system for ozone decomposition but also contributes valuable insights into developing more efficient catalysts to mitigate ozone pollution. [ABSTRACT FROM AUTHOR]

Oxygen defects are introduced into PbZr0.5Ti0.5O3 films and their impact on ferroelectric behavior, linear dielectric response (LDR), and nonlinear dielectric response (NDR) is studied. Apart from a notable decrease in both polarization and LDR permittivity, the frequency spectra of LDR exhibit a distinctive loss peak. The peak position varies with temperature and oxygen defect concentration. NDR parameters, including the Rayleigh coefficient (α1), the slope (α2) correlating the imaginary part of permittivity with the ac electric field, and the slope (k) between the real and the imaginary parts of permittivity, demonstrate diverse behaviors in response to temperature and oxygen defect concentration. The similarity in the frequency spectra of tanδ and 1/k reveals the correlation between LDR and NDR induced by the presence of oxygen defects. These observations are attributed to the behavior of the single and composite defects associated with oxygen vacancies. [ABSTRACT FROM AUTHOR]

A fundamental equation of state in terms of the Helmholtz energy is presented for mixtures of nitrogen, oxygen, and argon at any composition. It is expressed in terms of the residual Helmholtz energy and can be used to calculate all thermodynamic equilibrium properties including vapor–liquid equilibria. The parameters of the equations for the pure-fluid and mixture contributions are fitted exclusively to molecular simulation data so that the model has a predictive character. The description of the mixture-specific reducing parameters is realized via generalized correlations of the critical parameters of the pure fluids so that an extension of the model to additional components can be implemented straightforwardly. Extensive comparisons to experimental data and the GERG-2008 reference equation of state show that the prediction of thermodynamic properties is satisfactory. [ABSTRACT FROM AUTHOR]

We present a method by which the direct detection effect in superconducting hot-electron bolometer mixers can be analytically accounted for with sufficient practical accuracy. This is achieved by means of the advanced uniform, non-linear two-temperature model that considers the effective temperatures of electrons and phonons alongside established material parameters. We demonstrate the efficacy of this approach for the ex situ correction of the radiance of the emission line of atomic oxygen under conditions when the direct detection causes a 30% error in the line magnitude. The correction was applied to data collected by a balloon-borne heterodyne receiver operating in the upper atmosphere of Earth. The corrected line shape and magnitude are in reasonable agreement with the predictions of atmospheric radiation transfer models. [ABSTRACT FROM AUTHOR]

Scandium nitride (ScN) is an attractive material for electronic applications due to its high n -type conductivity. Native defects and unintentional impurities may limit its electron concentration and reduce its mobility; therefore, it is important to control their formation and incorporation. Hydrogen and oxygen are unintentional impurities that are commonly present during growth and processing. They act as shallow donors in ScN and hence may be regarded as harmless or even favorable to achieving n -type conductivity. Here we show, using state-of-the-art first-principles calculations, that these impurities can be detrimental because they readily form complexes with scandium vacancies (V Sc ). Isolated V Sc have relatively high formation energies and thus have low concentrations and little impact on electronic properties. However, complexes between V Sc and either hydrogen or oxygen form more readily than the pristine vacancy and will act as both compensating and scattering centers. Our results point to the importance of controlling the incorporation of hydrogen and oxygen in ScN (and AlScN alloys) to avoid degradation of the electronic properties. [ABSTRACT FROM AUTHOR]

In this work, bottom-Schottky-structure InGaZnOx (IGZO) Schottky barrier diodes (SBDs) with sputtered PtOx anodes were fabricated and annealed in oxygen at different temperatures. Critical parameters and negative bias stress (NBS) stability of SBDs with different annealing temperatures are investigated. With the annealing temperature increases, the barrier height and rectification ratio of the SBDs exhibited a rising-then-declining trend, while the ideality factor slightly increased until 200 °C. The SBDs show up overall reliability except for a leakage current rising trend under light, which can be attributed to free electron generation from the ionized oxygen vacancy. Among all the SBDs, the 175 °C annealed ones exhibited the best overall performance, including a high barrier height of 0.89 eV, an ideality factor of 1.14, and a large rectification ratio of over 108. Compared to the initial SBDs, the annealed ones showed up great improvement in NBS stability except for the 200 °C annealed ones, which was permanently degraded and not able to recover to original states. According to experimental result analysis and IGZO material characteristics, a stability model based on the subgap trap transition from V O 2 + to VO and new V O 2 + creation was proposed, which applies to both the short-term and long-term NBS tests. The results above demonstrate that oxygen annealing at appropriate temperature is an effective method to improve both device performance and NBS stability for PtOx–IGZO SBDs. [ABSTRACT FROM AUTHOR]

This study analyzes the regulatory mechanism of oxygen vacancy concentration on tail-to-tail charged domain walls (T–T CDWs), along with the writing time, conduction current magnitude, and retention performance of through-type T–T CDWs. The research results show that the highest density and length of T–T CDWs are achieved when the oxygen vacancy concentration is 1 × 1020 cm−3. Moreover, the successful writing of through-type T–T CDWs is limited to a certain electric field range, which is controlled by oxygen vacancy concentration. An increase in the oxygen vacancy concentration leads to a decrease in the maximum and minimum threshold electric fields required for writing through-type charged domain walls. The writing time and conductivity of through-type T–T CDWs determine the information writing speed and signal strength of domain wall memories, and the oxygen vacancy concentration also plays a regulatory role in both aspects. When the oxygen vacancy concentration is 1 × 1020 cm−3, the through-type T–T CDW exhibits the fastest writing speed, requiring only 8 ns. The magnitude of the conduction current of through-type T–T CDWs is directly proportional to the oxygen vacancy concentration. The through-type T–T CDWs formed by the aggregation of oxygen vacancies exhibit excellent retention performance, making them highly promising for applications in ferroelectric domain wall memories. Our research demonstrates that oxygen vacancies have a significant regulatory effect on the morphology and current response of charged domain walls, opening up new avenues for the study of domain wall memories. [ABSTRACT FROM AUTHOR]

In view of the inherent pseudocapacitance, rich redox pairs (Nb5+/Nb4+ and Nb4+/Nb3+), and high lithiation potential (1.0–3.0 V vs Li/Li+), Nb2O5 is considered a promising anode material. However, the inherent low electronic conductivity of Nb2O5 limits its lithium storage performance, and the rate performance after carbon modification is still unsatisfactory because the intrinsic conductivity of Nb2O5 has not been substantially improved. In this experiment, taking the improvement of the intrinsic electrical conductivity of Nb2O5 as the guiding ideology, we prepared F-doped Nb2O5@fluorocarbon composites (F–Nb2O5@FC) with a large number of oxygen vacancies by one-step annealing. As the anode electrode of lithium-ion batteries, the reversible specific capacity of F–Nb2O5@FC reaches 150 mA g−1 at 5 A g−1 after 1100 cycles, and the rate performance is particularly outstanding, with a capacity up to 130 mA g−1 at 16 A g−1, which is far superior to other Nb2O5@carbon-based anode electrodes. Compared with other single conductivity sources of Nb2O5@carbon-based composites, the electrical conductivity of F–Nb2O5@FC composites is greatly improved in many aspects, including the introduction of free electrons by F− doping, the generation of oxygen vacancies, and the provision of a three-dimensional conductive network by FC. Through analytical chemistry (work function, UV–Vis diffuse reflectance spectroscopy, and EIS) and theoretical calculations, it is proved that F–Nb2O5@FC has high electrical conductivity and realizes rapid electron transfer. [ABSTRACT FROM AUTHOR]

Amorphous ice phases are key constituents of water's complex structural landscape. This study investigates the polyamorphic nature of water, focusing on the complexities within low-density amorphous ice (LDA), high-density amorphous ice, and the recently discovered medium-density amorphous ice (MDA). We use rotationally invariant, high-dimensional order parameters to capture a wide spectrum of local symmetries for the characterization of local oxygen environments. We train a neural network to classify these local environments and investigate the distinctiveness of MDA within the structural landscape of amorphous ice. Our results highlight the difficulty in accurately differentiating MDA from LDA due to structural similarities. Beyond water, our methodology can be applied to investigate the structural properties and phases of disordered materials. [ABSTRACT FROM AUTHOR]

Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (E C R). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on E C R at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in E C R upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable E C R is achieved. A higher contact voltage accelerates E C R stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches. [ABSTRACT FROM AUTHOR]

Fetal neural stem cells (NSCs) physiologically reside under low-oxygen conditions (1%–5% of tissue pO2), but are often transferred and maintained under atmospheric oxygen levels of 21% pO2 (hyperoxia) for in vitro investigations. These altered oxygen conditions lead to adaptive changes in NSCs which complicate the interpretation of in vitro data. However, the underlying adaption dynamics remain largely enigmatic. Here we investigated short-term hyperoxia effects (5 days in 3% pO2 followed by 2 days in 21% pO2) in comparison to continuous hyperoxia effects (7 days in 21% pO2) and physioxic control (7 days in 3% pO2). We utilized cortical NSCs to analyze the cell cycle phases by flow cytometry and cumulative BrdU incorporation assay. NSCs showed a severe reduction of cell proliferation when cultivated under continuous hyperoxia, but no changes after short-term hyperoxia. Subsequent cell cycle analysis as assessed by flow cytometry revealed a clear shift of NSCs from G0/G1-phase towards S- or G2/M-phase after both continuous and short-term hyperoxia. However, while cell cycle length was dramatically reduced by short-term hyperoxia, it was increased during continuous hyperoxia. Taken together, our results demonstrate the beneficial effect of physioxia for expanding NSCs in vitro and reveal differential effects of short-term hyperoxia compared to continuous hyperoxia. [ABSTRACT FROM AUTHOR]

Iron (Fe) reduction is one of the oldest microbial processes on Earth. After the atmosphere and ocean became oxygenated, this anaerobic process was relegated to niche anoxic environments. However, evidence of Fe reduction in oxic, partially saturated subsurface systems, such as soils and vadose zones, has been reported, with the common explanation being the formation of anoxic microsites that remain undetected by bulk measurements. To explore how microscale oxygen concentrations regulate microbial Fe reduction, we cultivated a facultative Fe-reducing bacterium using a microfluidic setup integrated with transparent planar oxygen sensors. Contrary to expectations, Fe reduction occurred under fully oxic conditions, without the formation of anoxic microsites. Our results suggest that microbially mediated Fe-reduction could be more widespread in oxic subsurface environments than previously assumed. Moreover, our mathematical modeling of oxygen dynamics around biomass-rich layers revealed that the onset of anoxia is mainly controlled by biomass spatial organization rather than the conventionally used water saturation index. This opens a new perspective on the proxies needed to predict anoxic microsite formation and Fe(III) reduction occurrence. [ABSTRACT FROM AUTHOR]

We reported an exogenous nitrogen-doped method to synthesize a bifunctional electrocatalyst with oxygen reduction and evolution reaction activity. This electrocatalyst displays excellent ORR (E1/2 = 0.9 V vs. RHE) and OER (potential E = 1.57 V at 10 mA cm−2) activity. [ABSTRACT FROM AUTHOR]

Human populations are experiencing unprecedented growth and longevity with lingering knowledge gaps of the characteristics, mechanisms, and pathologies of senescence. Invasive measurements and long-term control conditions for longitudinal studies are infeasible, necessitating the need for surrogate animal models. Rats have short lifespans (2–3 years) with translatable cardiovascular systems, and Sprague Dawley microcirculatory preparations are key to studying the oxygen transport mechanisms critical to the loss of skeletal muscle function in aging. Here we present baseline physiological data of 61 male, Sprague Dawley rats at 3, 6, 12, 18, and 24 months of age. Anesthetized animals were surgically prepared for femoral arterial and venous cannulations, tracheal intubation, and exteriorization of the spinotrapezius muscle. Measurements included cardiovascular function, blood gases, and peripheral tissue interstitial oxygen tension (PISFO2) using phosphorescence quenching microscopy. Intrinsic heart rates decreased with age without significant changes to blood pressure. Arterial oxygen tension declined 17% by 18 and 24 Months (p < 0.05) while pACO2 and PISFO2 were unchanged. Lactate was elevated at 12 and 18 Months along with an alkaline shift in blood pH. Heart rate and decreased pAO2 decoupled from pACO2 are conserved phenomena in human aging. The continuity of resting PISFO2 despite an anaerobic shift in metabolism may be due to declining mitochondrial function and dysregulation of the vascular response to hypoxemia, which are also present in aged humans. These physiological and microcirculatory data offer a useful experimental model for investigating the detailed changes in oxygen supply and demand that affect senescing skeletal muscles in rats and humans. [ABSTRACT FROM AUTHOR]

Metasomatism refers to the process during which a pre-existing rock undergoes compositional and mineralogical transformations associated with chemical reactions triggered by the reaction of fluids which invade the protolith. It changes chemical compositions of minerals, promotes their dissolution and precipitation of new minerals. In this paper, we review metasomatic alteration of type 3 ordinary (H, L, LL) and carbonaceous (CV, CO, CK) chondrites, including (i) secondary mineralization, (ii) physicochemical conditions, (iii) chronology (53Mn-53Cr, 26Al-26Mg, 129I-129Xe) of metasomatic alteration, (iv) records of metasomatic alteration in H, O, N, C, S, and Cl isotopic systematics, (v) effects of metasomatic alteration on O- and Al-Mg-isotope systematics of primary minerals in chondrules and refractory inclusions, and (vi) sources of water ices in metasomatically altered CV, CO, and ordinary chondrites, and outline future studies. [ABSTRACT FROM AUTHOR]

This investigation looks at the structural and optical properties of g-C3N4 (graphitic carbon nitride) and its doped analogs, indicated as x@g-C3N4 (where x indicates oxygen, potassium, and nitrogen). The study investigates the effect of these dopants on the material's physicochemical properties, focusing on their applicability for photocatalytic applications. The alterations in crystallinity and shape caused by doping were shown by structural and functional analyses utilising XRD, FTIR, SEM, and XPS analysis. UV-DRS and PL measurements of optical characteristics revealed bandgap changes and charge recombination due to dopant inclusion. The photodegradation performance of organic pollutants under visible light was examined, indicating the improved photocatalytic activity of oxygen-doped g-C3N4 compared to the pristine and other doped materials. Adsorption capabilities and scavenger tests were explored to better understand reactive species' role in the photocatalytic process. Furthermore, VB-XPS analysis, combined with UV-DRS and scavenger results, allowed us to propose a comprehensive photocatalytic mechanism. This research not only increases our understanding of the structural and optical impacts of doping on g-C3N4, but it also sheds light on the complexities of its photocatalytic behaviour, paving the road for its use in environmental remediation and sustainable energy conversion. [ABSTRACT FROM AUTHOR]

Binder jetting requires the sintering of green parts to reach the properties of a metallic component. The sintering activity and sintered material properties of stainless steels are sensitive to powder oxidation and binder contamination, which are introduced by improper debinding. Air is often used during thermal debinding as oxygen aids binder removal, but the metal powder is oxidised being detrimental to sintering densification and final material properties. Hence, the impact of decreasing oxygen content in the debinding atmosphere on the sintering of 17-4 PH at 1300°C for 2 h in an inert argon atmosphere was investigated. Debinding in oxygen-containing atmospheres revealed the presence of δ-ferrite in the sintered microstructure, enhancing densification during sintering. Debinding in an inert Ar atmosphere resulted in low densification that was correlated to the absence of δ-ferrite due to the high amount of carbon in the sintered part. The high carbon content after debinding in Ar resulted in nearly complete oxygen removal by carbothermal reduction during sintering. Debinding in Ar + 1 vol.% O2 achieved the best combination of reducing final oxygen content by 46% via carbothermal reduction and the absence of carbon pickup during debinding and sintering. Debinding in processing atmospheres containing 3 vol.% O2 up to 20 vol.% O2, in contrast, led to a significant oxygen increase of 53 to 74% after sintering compared to the virgin powder. [ABSTRACT FROM AUTHOR]

Binder jetting (BJT) utilises a sacrificial binder to shape green parts in a metal powder bed. The binder must be removed during debinding at elevated temperatures without contaminating the powder material. Efficient binder removal often requires oxygen in the atmosphere to aid the decomposition of the binder, but oxygen causes oxidation of the metal powders and hence negatively impacts the final material properties. Therefore, the use of tailored oxygen contents in the atmosphere during a standard debinding cycle performed at 300°C for 2 h was investigated for BJT printed 17-4 PH stainless steel. The change in bulk chemistry (carbon, oxygen, nitrogen, and hydrogen) from green parts to brown parts was thoroughly analysed and compared to the virgin powder subjected to the same conditions as used for debinding. While inert argon was beneficial for protecting the powder from oxidation, the removal of only ∼34% of binder was insufficient, resulting in 0.47 wt.% of residual carbon in the brown part. Debinding in atmospheres containing 3 vol.% O2 to 20 vol.% O2 led to almost complete binder removal, but also caused significant oxygen pickup by the powder between 1734 ppm and 1820 ppm. Furthermore, the brittleness of the brown parts increased, leading to undesirable powder losses during handling. The best debinding was obtained in Ar + 1 vol.% O2, which allowed the best combination of binder removal of ∼74% and lower oxygen pickup by the powder of 1617 ppm, together with sufficient brown part strength for handling. [ABSTRACT FROM AUTHOR]

Obesity is a complex, multifactorial, chronic disease that acts as a gateway to a range of other diseases. Evidence from recent studies suggests that changes in oxygen availability in the microenvironment of metabolic organs may exert an important role in the development of obesity-related cardiometabolic complications. In this review, we will first discuss results from observational and controlled laboratory studies that examined the relationship between reduced oxygen availability and obesity-related metabolic derangements. Next, the effects of alterations in oxygen partial pressure (pO2) in the adipose tissue, skeletal muscle and the liver microenvironment on physiological processes in these key metabolic organs will be addressed, and how this might relate to cardiometabolic complications. Since many obesity-related chronic diseases, including type 2 diabetes mellitus, cardiovascular diseases, chronic kidney disease, chronic obstructive pulmonary disease and obstructive sleep apnea, are characterized by changes in pO2 in the tissue microenvironment, a better understanding of the metabolic impact of altered tissue oxygenation can provide valuable insights into the complex interplay between environmental and biological factors involved in the pathophysiology of metabolic impairments. This may ultimately contribute to the development of novel strategies to prevent and treat obesity-related cardiometabolic diseases. [ABSTRACT FROM AUTHOR]

Purpose: The shape and position of the hemoglobin-oxygen dissociation curve (ODC) is of critical importance in medicine, as it determines the uptake of O2 in the lungs and the delivery of O2 to the tissues. Numerous reports have identified affinity-modulating effects of drugs in humans. Such effects may be relevant to conditions such as pulmonary diffusion disorders, peripheral vascular disease, or coronary artery disease. The aim of this scoping review was to assess and summarize the current evidence on these effects. Methods: The review was based on the PRISMA-ScR guidelines. We searched PubMed and the Cochrane Library and only included papers with free full-text access. The search covers all papers published before September 2024 and used the following keywords: "Oxygen affinity" or "oxygen dissociation curve" in combination with > 100 substance classes that should cover most drugs in clinical use. Results: The search returned 2447 hits of which 80 were selected for further full text review. In terms of discipline, cardiology accounted for the largest proportion, and in terms of effect quality, a right-ward shift resulting in improved tissue oxygenation was most common. For example, quantitative data show an increase in P50 of 6.1–12.4% and 25–53% for propranolol and RSR13, respectively. Conclusion: Despite a substantial body of data, the effects of the vast majority of drugs on the ODC have not been studied or have not been studied in sufficient detail. The undeniable potential for medical interventions to alter the ODC calls for revival of this area of research. [ABSTRACT FROM AUTHOR]

Oxygen availability is a key factor in the evolution of multicellularity, as larger and more sophisticated organisms often require mechanisms allowing efficient oxygen delivery to their tissues. One such mechanism is the presence of oxygen-binding proteins, such as globins and hemerythrins, which arose in the ancestor of bilaterian animals. Despite their importance, the precise mechanisms by which oxygen-binding proteins influenced the early stages of multicellular evolution under varying environmental oxygen levels are not yet clear. We address this knowledge gap by heterologously expressing the oxygen-binding proteins myoglobin and myohemerythrin in snowflake yeast, a model system of simple, undifferentiated multicellularity. These proteins increased the depth and rate of oxygen diffusion, increasing the fitness of snowflake yeast growing aerobically. Experiments show that, paradoxically, oxygen-binding proteins confer a greater fitness benefit for larger organisms when O2 is least limiting. We show via biophysical modeling that this is because facilitated diffusion is more efficient when oxygen is abundant, transporting a greater quantity of O2 which can be used for metabolism. By alleviating anatomical diffusion limitations to oxygen consumption, the evolution of oxygen-binding proteins in the oxygen-rich Neoproterozoic may have been a key breakthrough enabling the evolution of increasingly large, complex multicellular metazoan lineages. How did early multicellular organisms manage to exploit rising oxygen levels? By modeling facilitated diffusion and expressing animal oxygen-binding proteins in snowflake yeast, this study shows that myoglobins and myohemerythrins circumvent anatomical limits to oxygen diffusion in multicellular organisms. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli (EHEC) is a contagious foodborne pathogen that specifically colonizes the human large intestine, which is regulated by different environmental stimuli within the gut. Transcriptional regulation of EHEC virulence and infection has been extensively studied, while the posttranscriptional regulation of these processes by small RNAs (sRNAs) remains not fully understood. Here we present a virulence-regulating pathway in EHEC O157:H7, in which the sRNA EvrS binds to and destabilizes the mRNA of Z2269, a novel transcriptional regulator. In turn, Z2269 indirectly activates the expression of LEE (locus of enterocyte effacement) pathogenicity island through the master regulator Ler. Importantly, the expression of EvrS is modulated by environmental oxygen levels. EvrS also exhibits lower expression in the colon compared to the ileum, influencing the site-specific colonization of EHEC O157:H7 in mice. These results indicate that the oxygen status within the intestine may regulate the expression of EvrS, thereby modulating virulence factors of EHEC and contributing to successful infection in vivo. This study has broader implications for understanding sRNA functions in spatiotemporal virulence control of EHEC and may provide novel strategies to prevent EHEC infections. [ABSTRACT FROM AUTHOR]

Oxygen therapy is ubiquitous in critical illness but oxygenation targets to guide therapy remain controversial despite several large randomised controlled trials (RCTs). Findings from RCTs evaluating different approaches to oxygen therapy in critical illness present a confused picture for several reasons. Differences in both oxygen target measures (e.g. oxygen saturation or partial pressure) and the numerical thresholds used to define lower and higher targets complicate comparisons between trials. The duration of and adherence to oxygenation targets is also variable with consequent substantial variation in both the dose and the dose separation. Finally, heterogeneity of treatment effects (HTE) may also be a significant factor. HTE is defined as non-random variation in the benefit or harm of a treatment, in which the variation is associated with or attributable to patient characteristics. This narrative review aims to make the case that such heterogeneity is likely in relation to oxygen therapy for critically ill patients and that this has significant implications for the design and interpretation of trials of oxygen therapy in this context. HTE for oxygen therapy amongst critically ill patients may explain the contrasting results from different clinical trials of oxygen therapy. Individualised oxygen therapy may overcome this challenge, and future studies should incorporate ways to evaluate this approach. [ABSTRACT FROM AUTHOR]

In this work, we present p-type Te-TeOx FETs with BEOL-compatibility targeting high-performance computing at cryogenic temperatures. The devices feature aggressively scaled channel lengths (Lch of 50 nm) deposited using the sputtering method that is cost-effective, large-scale manufacturable, and highly controllable. We investigated the effects of oxygen content and film thickness in the sputtered channel layer on device performance. The device achieves a maximum transconductance (Gm, max) of 142 μS/μm, an on/off ratio exceeding 3 × 108, a subthreshold swing (SS) of 99 mV/Dec., a high hole mobility of 28.6 cm2/V s, and excellent NBTI and PBTI reliability characteristics at 77 K. [ABSTRACT FROM AUTHOR]

A photocatalytic oxo-hydrazination of α-diazoacetates with azobenzenes has been developed. With air as an oxygen source, the reaction proceeded smoothly and afforded previously unknown N,N′-diarylhydrazino-containing oxoacetates. Mechanistically, the reaction is enabled by cooperation of photoredox catalysis, energy transfer photocatalysis and direct photoexcitation. [ABSTRACT FROM AUTHOR]

The surface lattice oxygen of ZnO was demonstrated to be critical for the nonoxidative dehydrogenation of ethanol, which combines with surface-exposed Zn to effectively produce acetaldehyde and the energy molecule hydrogen. [ABSTRACT FROM AUTHOR]

Purpose: Trapeziometacarpal osteoarthritis (TMC-OA) is a prevalent hand disorder affecting a growing number of people worldwide. While a multidisciplinary approach might provide additional advantages, the analgesic and anti-inflammatory role of intra-articular oxygen-ozone (O2O3) injections combined with physical therapy is still unknown. To assess the impact of a multimodal therapeutic approach combining O2O3 injections with physical therapy in patients with TMC-OA. Materials and methods: A prospective open-label study conducted in the Physical and Rehabilitation Medicine Unit of the "Renato Dulbecco" University Hospital of Catanzaro. We assessed patients with TMC-OA who had not responded to standard medical therapy. Participants received O2O3 therapy and targeted physical therapy for 4 weeks. Pain relief, muscle strength, and physical functioning were assessed at baseline and after 4, 12 and 24 weeks (respectively T0, T1, T2, and T3) Results: Seventeen patients with a mean age of 67.1 ± 6.1 years were included in the study. Short-term improvements in pain intensity were observed (T0: 6.221 ± 1.514; T1: 3.172 ± 1.1451; p <.001) and were maintained over a 24-week follow-up period (T0: 6.221 ± 1.514; T3: 4.393 ± 1.438; p: 0.006). Significant changes were reported also in terms of muscle strength and physical functioning. O2O3 therapy was well-tolerated with no adverse effects. Conclusions: A combination of O2O3 injections and physical therapy might be considered in patients with TMC-OA. Further investigation is warranted to assess the effectiveness of O2O3 therapy in managing TMC-OA. IMPLICATIONS FOR REHABILITATION: The addition of intra-articular trapeziometacarpal O2O3 injections to physical therapy is safe and reliable for thumb osteoarthritis O2O3 injection could be considered a second-line mini-invasive approach option when simple analgesic and non-pharmacologic interventions have failed, and surgical treatment is not yet indicated O2O3 injections in combination with physical therapy may provide benefits in terms of pain relief in patients with TMC joint OA in whom previous conventional medical therapy has been unsuccessful [ABSTRACT FROM AUTHOR]

Background: As iatrogenic hyperoxia has been related to adverse outcomes in critically ill patients, guidelines advise to titrate oxygen to physiological levels. In the prehospital setting where partial arterial oxygen (PaO2) values are often not readily available, titration of oxygen is based on peripheral oxygen saturations (SpO2). In this study we aimed to investigate the efficacy of SpO2 guided oxygen titration in the prevention of hyperoxia. Methods: In a retrospective observational cohort study of patients included in the Acutelines data- and biobank of the University Medical Center Groningen between September 2020 and March 2023, we collected blood gas samples and triage data of sequentially included patients who received oxygen at the moment they were presented in the emergency department (ED). PaO2 values were compared to (concurrently measured) SpO2 values, and to patient- and treatment characteristics and P/F ratios were calculated in order to investigate the efficacy of SpO2 based oxygen titration for various subgroups. Results: Blood gas samples were obtained for 1042 patients, of which 178 (17.1%) had hyperoxia (PaO2 levels > 13.5 kPa). SpO2 readings were available for 170 of these, 68 of which (40%) had SpO2 values above the recommended target range (94–98%; 88–92% for patients with COPD) whereas 102 patients (60%) had SpO2 values within- or even below the recommended target range. Many of these patients (44.1%) received oxygen through a low-flow device (nasal canula), and these patients almost invariably (84.4%) were not compromised in their ventilation (P/F ratio's > 300). Conclusion: When oxygen is titrated based on SpO2 levels, this results in hyperoxemia in a significant proportion of the patients. Health care providers should especially be reluctant to administer (low flow) oxygen as a standard of care to patients who do not have clear respiratory compromise, as these patients are at a high risk of developing (occult) hyperoxia. [ABSTRACT FROM AUTHOR]

Purpose: The simplified Chinese version of the Dyspnoea-12 Questionnaire (D-12) has not yet been translated and validated for patients with primary lung cancer. This study aimed to evaluate the psychometric properties of the simplified Chinese version of the D-12 for patients with primary lung cancer. Methods: This study analysed the baseline data of a randomised controlled trial that used an inspiratory muscle training intervention for patients with thoracic malignancies. The original English version of the D-12 was translated into simplified Chinese according to standard instrument translation and adaptation procedures. The internal consistency reliability of the D-12 was determined by calculating Cronbach's alpha coefficients. The convergent validity of the D-12 was evaluated by Spearman's correlation with the Borg CR-10 Scale, Numerical Rating Scale (NRS), Hospital Anxiety and Depression Scale (HADS), and Saint George's Respiratory Questionnaire (SGRQ). Blood oxygen level, the 6-minute walk test distance, alcohol use, surgery type, cancer stage, exercise level, and educational background were identified to evaluate their discriminating performance. Results: The analysis included 196 participants. The Cronbach's alpha coefficients for the full D-12 and its physical and emotional function subscales were 0.83, 0.74, and 0.92, respectively. Significantly positive associations were found between the D-12 scores and the Borg CR-10 Scale, the NRS, the HADS, and SGRQ scores (p < 0.01). The participants with insomnia (p < 0.01) and who did not use alcohol (p = 0.019) reported significantly higher D-12 total scores compared with their respective counterparts. The participants at different cancer stages (p < 0.01) and those who had undergone different surgeries (p = 0.033) reported significantly different D-12 total scores. Conclusions: The D-12 simplified Chinese version demonstrated very good psychometric properties and high acceptability in patients with primary lung cancer. [ABSTRACT FROM AUTHOR]

Although alveolar hyperoxia exacerbates lung injury, clinical studies have failed to demonstrate the beneficial effects of lowering the fraction of inspired oxygen (FIO2) in patients with acute respiratory distress syndrome (ARDS). Atelectasis, which is commonly observed in ARDS, not only leads to hypoxemia but also contributes to lung injury through hypoxia-induced alveolar tissue inflammation. Therefore, it is possible that excessively low FIO2 may enhance hypoxia-induced inflammation in atelectasis, and raising FIO2 to an appropriate level may be a reasonable strategy for its mitigation. In this study, we investigated the effects of different FIO2 levels on alveolar tissue hypoxia and injury in a mechanically ventilated rat model of experimental ARDS with atelectasis. Rats were intratracheally injected with lipopolysaccharide (LPS) to establish an ARDS model. They were allocated to the low, moderate, and high FIO2 groups with FIO2 of 30, 60, and 100%, respectively, a day after LPS injection. All groups were mechanically ventilated with an 8 mL/kg tidal volume and zero end-expiratory pressure to induce dorsal atelectatic regions. Arterial blood gas analysis was performed every 2 h. After six hours of mechanical ventilation, the rats were euthanized, and blood, bronchoalveolar lavage fluid, and lung tissues were collected and analyzed. Another set of animals was used for pimonidazole staining of the lung tissues to detect the hypoxic region. Lung mechanics, ratios of partial pressure of arterial oxygen (PaO2) to FIO2, and partial pressure of arterial carbon dioxide were not significantly different among the three groups, although PaO2 changed with FIO2. The dorsal lung tissues were positively stained with pimonidazole regardless of FIO2, and the HIF-1α concentrations were not significantly different among the three groups, indicating that raising FIO2 could not rescue alveolar tissue hypoxia. Moreover, changes in FIO2 did not significantly affect lung injury or inflammation. In contrast, hypoxemia observed in the low FIO2 group caused injury to organs other than the lungs. Raising FIO2 levels did not attenuate tissue hypoxia, inflammation, or injury in the atelectatic lung region in experimental ARDS. Our results indicate that raising FIO2 levels to attenuate atelectasis-induced lung injury cannot be rationalized. [ABSTRACT FROM AUTHOR]

Agroforestry is an alternative land use practice that holds promise for societal benefits and the attainment of ecosystem sustainability. The objectives of this study were to evaluate the tree diversity, carbon sequestration, soil carbon pool, oxygen production and rice productivity under traditional agroforestry systems at different elevations in the Garhwal Himalayan region of India. Tree diversity, carbon sequestration and oxygen production were quantified by field measurements (using 0.04 ha quadrats) and subsequent calculations. Rice productivity was assessed using grain yield, straw yield and biological yield, while soil properties were analyzed in the laboratory using standard methods. Results of the study showed that tree diversity was higher at the 1200–1600 m elevation and had a maximum Shannon Diversity Index (1.29) and Simpson Diversity Index (0.69). The 1600–2000 m elevation stored more carbon (34.43 Mg ha−1) and total oxygen production (91.79 Mg ha−1). Among the agroforestry trees, Quercus leucotrichophora, Melia azedarach and Prunus cerasoides showed the highest carbon storage and total oxygen production. Elevation and soil depth were found to affect the soil properties. The agroforestry systems had higher soil organic carbon and lower bulk density than sole cropping systems. Compared to the agroforestry system, the monoculture produced more rice (Oryza sativa). The study shows that traditional agroforestry is a valuable tool for carbon sequestration and soil improvement, albeit with potential compromises in crop productivity. It emphasises the need for tailored management approaches to harness the ecological and environmental benefits of agroforestry in the Himalayas. This study draws attention to the potential of traditional agroforestry in the Garhwal Himalaya for carbon sequestration, climate change mitigation and soil quality improvement which provides a reference for striking a balance between the ecological advantages of agroforestry and the socio-economic considerations of local communities. However, it also underlines the importance of considering trade-offs between environmental benefits and crop yields when implementing such agroforestry systems. Highlights: • Elevation plays an important role for tree diversity, net carbon sequestration and net oxygen production in Himalaya. • Compared to sole cropping system, agroforestry systems had higher soil pH and soil organic carbon, along with lower bulk density. • Production was high in sole cropping system while agroforestry had ecological benefits like carbon storage and soil improvement. [ABSTRACT FROM AUTHOR]

Background: Continuous veno-venous hemodiafiltration (CVVHDF) is used in critically ill patients, but its impact on O₂ and CO₂ removal, as well as the accuracy of resting energy expenditure (REE) measurement using indirect calorimetry (IC) remains unclear. This study aims to evaluate the effects of CVVHDF on O₂ and CO₂ removal and the accuracy of REE measurement using IC in patients undergoing continuous renal replacement therapy. Design: Prospective, observational, single-center study. Methodology: Patients with sepsis undergoing CVVHDF had CO₂ flow (QCO₂) and O₂ flow (QO₂) measured at multiple sampling points before and after the filter. REE was calculated using the Weir equation based on V̇CO₂ and V̇O₂ measured by IC, using true V̇CO₂ accounting for the CRRT balance, and estimated using the Harris-Benedict equation. The respiratory quotient (RQ), the ratio of V̇CO₂ to V̇O₂, was evaluated by comparing measured and true values. Results: The mean QCO₂ levels measured upstream of the filter were 76.26 ± 17.33 ml/min and significantly decreased to 62.12 ± 13.64 ml/min downstream of the filter (p < 0.0001). The mean QO₂ levels remained relatively unchanged. The mean true REE was 1774.28 ± 438.20 kcal/day, significantly different from both the measured REE of 1758.59 ± 434.06 kcal/day (p = 0.0029) and the estimated REE of 1619.36 ± 295.46 kcal/day (p = 0.0475). The mean measured RQ value was 0.693 ± 0.118, while the mean true RQ value was 0.731 ± 0.121, with a significant difference (p < 0.0001). Conclusions: CVVHDF may significantly alter QCO₂ levels without affecting QO₂, influencing the REE and RQ results measured by IC. However, the impact on REE is not clinically significant, and the REE value obtained via IC is closer to the true REE than that estimated using the Harris-Benedict equation. Further studies are recommended to confirm these findings. [ABSTRACT FROM AUTHOR]

Introduction: Temperature and oxygen are two factors that profoundly affect survival limits of animals; too much or too little of either is lethal. However, humans and other animals can exhibit exceptional survival when oxygen and temperature are simultaneously low. This research investigates the role of oxygen in the cold shock death of Caenorhabditis elegans. Methods: The survival of C. elegans populations in combinations of oxygen concentrations and was assayed. Additionally, the effect of cold acclimatization, mutations in the cold acclimatization pathway, compounds, and antioxidant proteins on survival in low temperatures and high oxygen were investigated. Results: We demonstrate that C. elegans have increased survival in 2°C when deprived of oxygen, and an increase to just 0.25 kPa of oxygen decreased survival. Additionally, we show that oxygen toxicity produced by a 35-fold increase above atmospheric oxygen levels was fatal for nematodes in 8 h at room temperature and 2 h at 2°C. We found that cold acclimatization and mutations in the cold acclimatization pathway improve survival in room temperature oxygen toxicity. Furthermore, we found that the compounds glucose, manganese (II), and ascorbate improve both cold shock and high oxygen survival, while the antioxidant proteins catalase and peroxiredoxin are essential to wild type survival in these conditions. Discussion: Our results suggest that oxygen toxicity contributes to the death of C. elegans during cold shock. The changes in survival induced by cold acclimatization and mutations in the cold acclimatization pathway suggest that oxygen toxicity in the cold exerts evolutionary pressure, leading to the development of protections against it. Additionally, the resistance provided by diverse compounds and antioxidant proteins in both low temperature and high oxygen suggests these conditions have similar chemical environments. We discuss evidence that similar phenomena may function in humans. [ABSTRACT FROM AUTHOR]

Objective: Microglial activation is a hallmark of pathogenic retinal conditions such as retinal ischemia-reperfusion (RIR). While sortilin-related vacuolar protein sorting 10 domain containing receptor 2 (Sorcs2) and laminin subunit alpha 1 (Lama1) have been implicated in neuroinflammatory processes, their roles in regulating microglial activation in RIR are not reported. The current work studied the potential of Sorcs2 and Lama1 as negative regulators of microglial activation in RIR and assessed the therapeutic potential of Astragalus polysaccharide (AP). Material and Methods: Transcriptome profiling was conducted in retinal specimens of RIR group 72 h after RIR induction. Oxygen-glucose deprivation/reperfusion (OGD/R) in rat microglial cells was employed as the cellular induction model of RIR. The functional role of Sorcs2 and Lama1 in dictating microglial activation was investigated in vitro and in vivo using lentivirus-based gene expression. Further, the potential effect of AP on RIR-mediated microglial activation was investigated. Results: Sorcs2 and Lama1 were identified as two downregulated genes in retinal samples following RIR. OGD/R induction triggered pro-inflammatory microglial activation and induced the downregulation of Sorcs2 and Lama1. Sorcs2 or Lama1 overexpression hindered OGD/R-induced microglial activation in vitro and attenuated inflammatory expansion of microglia cells in RIR-induced rat retinal samples. AP treatment was able to neutralize the oxidative stress, promote the expression of Sorcs2 and Lama1, and suppress microglial activation. Conclusion: Our findings pinpoint Sorcs2 and Lama1 as negative regulators of microglial activation in RIR. AP could be employed as an antioxidant to attenuate microglial activation and ameliorate the inflammatory damages in RIR. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Redox potential is a solution property that influences specific yeast and bacterial activities and the rate of fermentation completion. There is a need to control it if reproducible fermentation outcomes are to be achieved and reliable conclusions are drawn at both the research and commercial scale of wine fermentation. Desirable outcomes that have been observed so far in wine fermentation include the prevention of sluggish and incomplete fermentations, an enhancement in cell viability, increases in the maintenance rate of non-growing cells, and the avoidance of hydrogen sulfide formation when elemental sulfur is present. Other expected fermentation outcomes include changes in the ratios of glycerol and succinate to ethanol, certain aroma and flavor components, and sulfite formation from sulfate in the juice. The juice composition determines the redox potential's initial value, and the yeast strain's interaction with the changing juice composition determines the pattern of the potential during fermentation. This interaction also establishes the dynamic response of the prevailing redox buffer to disturbances and the ability to control the potential during fermentation. The chemical reaction sequence, entities, and speciation thought to be responsible for establishing the redox potential in juices and wine are described. A quantitative model for control purposes remains elusive. Examples of the role of added iron in juice, different yeast strains, ambient light, and the addition of external hydrogen peroxide on the response of the potential are presented. Recent examples of controlling the redox potential during white wine and red wine fermentation at a commercial scale are presented, and areas for future research are identified. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) membranes have found diverse applications, such as in wastewater treatment, lithium-ion batteries, and pharmaceuticals, due to their low cost, excellent mechanical properties, thermal stability, and chemical resistance. However, the intrinsic hydrophobicity of PP materials leads to membrane fouling and filtration flux reduction, which greatly hinders the applications of PP membranes. Dielectric barrier discharge (DBD) is an effective technique for surface modification of materials because it generates a large area of low-temperature plasma at atmospheric pressure. In this study, O2 was added to nanosecond pulsed Ar DBD to increase its reactivity. Electrical and optical diagnostic techniques were used to study the discharge characteristics of the DBD at varying O2 contents. The uniformity of the discharge was quantitatively analyzed using the observed discharge images. Water contact angle measurements were used to assess the surface hydrophilicity of polypropylene. The surface morphology and chemical composition of the PP materials before and after treatment were analyzed using field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The results show that the moderate addition of O2 enhances surface hydrophilicity and the uniformity of the modification. By increasing the O2 addition from 0% to 0.1%, the average power increased from 4.19 W to 5.79 W, and the energy efficiency increased from 17.78% to 21.51%. The water contact angle of the DBD-treated PP showed a tendency to decrease and then increase with increasing O2 content, with the optimum O2 addition determined to be 0.1%. Under this condition, the water contact angle of the PP surface decreased by 31.88°, which is 52.31% lower than the untreated surface. O2 increases the number of oxygen-containing polar groups (-OH, C=O, and O-C=O) on the surface of the material, and deepens and densifies the grooves on the surface of the PP material, resulting in an increase in the hydrophilicity of the PP surface. [ABSTRACT FROM AUTHOR]

Background: In low- and middle-income countries (LMIC), 45% of deaths could be addressed by implementation of an emergency medical services (EMS) system. Prehospital care is a critical component of EMS worldwide, and basic, affordable training has been shown to improve EMS systems. However, patient outcome impact is unclear. In this study we aimed to assess the current state of prehospital care in Kigali, Rwanda, through a needs assessment, focused training intervention, and analysis of current practices and patient outcomes. Methods: Weidentified 30 clinicians through the prehospital medical command office and included them in the study. A prospective, nonrandomized, interrupted time-series approach was used. Data collected through closed- and open-ended questionnaires included age, sex, training, and knowledge assessment. We used the data to create a tailored, 18-hour training after which immediate and 11-month post-tests were administered. Linked prehospital and hospital care datasets allowed for evaluation of patient outcomes and prehospital process indicators that included training skill application, airway intervention, intravenous fluid administration, and glucose administration. Results: Of 30 clinicians, 18 (60%) were female, 19 were nurses, and 11 were nurse anaesthetists. Median age was 36, and median years providing care was 10 (IQR 7-11). Twenty-four (80%) participants completed immediate and post-test assessments. Mean knowledge across 12 core skills significantly improved from a pre-test mean of 59.7% (95% confidence interval [CI] 42.2-77.20) to a post-test mean of 87.8% (95% CI 74.7-100). At 11 months post-training, the score improvement maintained, with a mean score of 77.6% (95% CI 59.2-96.8). For patient outcomes, the total sample size was 572 patients; 324 of these patients were transported to the ED during the pre-training period (56.4%), while 248 were transported post-training. Prehospital oxygen administration for patients with a saturation level of <95%significantly increased pre-to post-training (66.7% to 71.7%; p= 5.0%; -95%CI 1.9,-8.1%). No significant changes were noted in patient treatment outcomes or other process indicators due to small sample sizes. Conclusion: This study provides insights on Rwandan EMS and demonstrates that a tailored intervention targeting education on prehospital process indicators has positive impacts on clinician knowledge and practice. [ABSTRACT FROM AUTHOR]

Introduction: This work calculates the microdosimetric spectra and evaluates the relative biological effectiveness (RBE10) of oxygen and carbon ions using Monte Carlo simulation. This study presents a fast, reliable radiation field characterisation and accurate biological dose prediction tool in charged particle therapy for heavy-ion beams using the Bridge silicon-on-insulator (SOI) microdosimeter via Tool for Particle Simulation (TOPAS)-based simulations toolkit. Method: The study used the TOPAS simulation to model the Bridge SOI microdosimeter and study its response to carbon beams with an energy of 290 MeV/u and oxygen beams with an energy of 345 MeV/u. Dose-mean lineal energy values $(\overline {{y_D})\;} $ and RBE10 values were evaluated using microdosimetric lineal energy spectra with the MKM model. Results and Conclusions: The results demonstrate that oxygen ion beams have an advantage for cancer treatment as they provide higher RBE10 values and occur at the same positions as the maximum physical dose (Bragg peak), compared to carbon ion beams. The study provides new understanding of RBE for carbon and oxygen ions, as well as the relationship between physical doses and RBE. [ABSTRACT FROM AUTHOR]

Photocatalytic overall splitting of pure water (H2O) without sacrificial reagent to hydrogen (H2) and oxygen (O2) holds a great potential for achieving carbon neutrality. Herein, by anchoring cobalt sulfide (Co9S8) as cocatalyst and cadmium sulfide (CdS) as light absorber to channel wall of a porous polymer microreactor (PP12), continuous violent H2 and O2 bubbling productions from photocatalytic overall splitting of pure H2O without sacrificial reagent is achieved, with H2 and O2 production rates as high as 4.41 and 2.20 mmol h−1 gcat.−1 respectively. These are significantly enhanced than those in the widely used stirred tank‐type reactor in which no O2 is produced and H2 production rate is only 0.004 mmol h−1 gcat.−1. Besides improved charge separation and interaction of H2O with photocatalyst in PP12, bonding interaction of Co9S8 with PP12 creates abundant catalytic active sites for simultaneous productions of H2 and O2, thus leading to the significantly enhanced H2 and O2 bubbling productions in PP12. This offers a new strategy to enhance photocatalytic overall splitting of pure H2O without sacrificial reagent. [ABSTRACT FROM AUTHOR]

Objective: To reflect upon our non-surgical respiratory management by evaluating clinical outcomes regarding airway, feeding, and growth during the first year of life in patients with Robin Sequence. Design: Prospective study. Setting: Sophia Children's Hospital, Rotterdam, the Netherlands. Patients/ Participants: 36 patients with Robin Sequence who were treated between 2011 and 2021. Interventions: Positional therapy and respiratory support. Main Outcome Measure(s): Data on respiratory outcomes included polysomnography characteristics and capillary blood gas values. Feeding outcomes were based on the requirement of additional tube feeding. Outcomes on growth were expressed as standard-deviation-scores (SDS) for weight-for-age (WFA) and height-for-age (HFA). Results: Twenty patients were treated with positional therapy (PT), whilst the other 16 patients required respiratory support. Twenty-two patients presented with non-isolated Robin Sequence (RS). During the first year of life, obstructive apnea hypopnea index decreased, oxygen levels enhanced, and capillary blood gas values improved. Eighty-six percent (31/36) experienced feeding difficulties, which completely resolved in 71% (22/31) during their first year of life. From start treatment, to stop treatment, to the age of 1 year, the SDS WFA worsened from −0.40 to −0.33 to −1.03, respectively. Conclusions: Non-surgical respiratory treatment resulted in an improvement of respiratory outcomes to near normal during the first year of life in patients with RS. These patients often experience feeding difficulties and endure impaired weight gain up to 1 year of age, despite near normalization of breathing. The high prevalence of feeding difficulties and impaired weight for age indicate the urgency for early recognition and adequate treatment to support optimal growth. [ABSTRACT FROM AUTHOR]

Copyright of Saudi Journal of Anaesthesia is the property of Wolters Kluwer India Pvt Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the photoelectric properties of Ag-based transparent conductive films, TCO/Ag/TCO multilayer films were prepared on K9 glass substrates with the magnetron sputtering. The dielectric TCO (transparent conductive oxide) layer was AZO (Al-doped ZnO, sputtered with or without oxygen) or ITO (Sn-doped In2O3, sputtered with oxygen). The effects of the combination of dielectric layers, and the AZO layer sputtering with or without oxygen were investigated. The results indicated that the crystallization quality of the Ag layer deteriorated and its roughness increased when the AZO layer was sputtered with oxygen, and the photoelectric properties of the multilayer film also notably decreased. Additionally, the film exhibited better photoelectric properties when the type of TCO on the top was different from that on the bottom. Among them, the crystallization quality of Ag layer was the best when the multilayer film was structured as ITO/Ag/AZO (sputtered without oxygen). This film exhibited a visible average transmittance of 82.36%, a sheet resistance of 9.11 Ω/sq, and a Figure-of-Merit (FOM) as high as 15.75 mΩ−1. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Metallurgical Quarterly is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the use of an oxygen pressure-based acid leaching process for the selective extraction of basic metals from a complex zinc ore containing high concentrations of lead (6.00%) and copper (2.47%). The effects of leaching temperature, ore particle size distribution, leaching time, liquid-to-solid ratio, and oxygen partial pressure on the leaching efficiencies of zinc and copper were investigated, and the phase transformation behaviour of lead compounds was studied. Under the optimal conditions that is, a particle size of −48/+40 μm, initial sulfuric acid concentration of 150 g/L, liquid-to-solid ratio of 6:1, leaching time of 150 min, leaching temperature of 150°C, and oxygen partial pressure of 0.8 MPa – the leaching efficiencies of zinc, copper, and iron were 98.85%, 82.69%, and 33%, respectively. The leaching residue showed that almost all of the zinc sulfide was dissolved as ZnSO4, and most of the negatively charged bivalent sulfur was converted to zero-valent element sulfur. Through the pressure leaching reaction, galena in the concentrate was converted to lead jarosite (PbFe6(SO4)4(OH)12) and elemental sulfur. The formation of lead jarosite facilitated the removal of a significant portion of iron during leaching, reducing the subsequent purification burden. [ABSTRACT FROM AUTHOR]

Introduction: Superimposed high-frequency jet ventilation (SHFJV) is a new type of jet ventilation that simultaneously uses high- and low-frequency types of jet ventilation. We compared SHFJV with the conventional high-frequency jet ventilation (CHFJV) in interventional bronchoscopy in terms of safety and effectiveness. Methods : A multi-centre prospective random single-blind clinical trial was conducted by three interventional bronchoscopy centres. Patients who underwent diagnostic or therapeutic bronchoscopy under general anaesthesia were admitted and divided into two groups: SHFJV group (trial group) and CHFJV group (control group). PaO2 and PaCO2 were recorded before anaesthesia and during and after the procedure. SpO2 and etCO2 were recorded every 10 min throughout the procedure. Patients were observed until 24 h post-bronchoscopy. Results: Sixty patients were included in the study. Twenty-nine were in the trial group, and 31 were in the control group. Both groups had no significant differences in demographic data. In the control group, the PaO2 measured in the operation was higher than that in the trial group (p = 0.023). The values of etCO2 in the control group were more dispersed than those of the trial group. When the procedure time was over 90 minutes, the etCO2 in the control group significantly increased (p = 0.01), while the etCO2 in trial group remained stable (p = 0.594). There were more patients with PaCO2 ≥ 50 mmHg during the procedure in the control group than in the trial group (p = 0.042). Conclusion : SHFJV is effective and safe in interventional bronchoscopy. It may provide more effective and stabilised ventilation than CHFJV in cases with long procedure times. [ABSTRACT FROM AUTHOR]

A novel solid electrolyte sensor with considerably improved response times is presented. The new so-called eFIPEX [etched flux (Φ) probe experiment] is based on the FIPEX [flux (Φ) probe experiment] sensor applied for the measurement of molecular and atomic oxygen concentrations. A main application is the measurement of atmospheric atomic oxygen aboard sounding rockets up to altitudes of 250 km. eFIPEX employs a new manufacturing technique for its electrodes combining two manufacturing steps—the deposition of platinum films with a polyol process and electrochemical etching to carve out the electrode geometry. Selectivity toward atomic oxygen is achieved through gold plating. All work steps can be completed in ambient air. Electrodes with thicknesses of 200 nm to 1.5 μm are manufactured and characterized with optical and electron microscopy as well as with energy dispersive x-ray spectroscopy. It is shown that the significantly faster response times are related to pores in the platinum film reaching down to the substrate. The new eFIPEX were flown in comparison with conventional FIPEX sensors on the PMWE-2 sounding rocket flight showing significantly improved performance. Due to the easier fabrication and the superior transient behavior, this new sensor system will be preferentially used in future missions. [ABSTRACT FROM AUTHOR]