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Long-latency auditory evoked potentials (LLAEPs) may help further advances in understanding consciousness under general anesthesia and promote more objective means of assessing sedation depth than conventional clinical signs. Among the LLAEP components, the auditory N1 shows promise as a measure of sedation depth and a marker of consciousness, but findings are so far inconclusive. Research with animals can help elucidate the effects of various anesthetics on the N1 and other LLAEPs, but investigations of LLAEPs under anesthesia in animals is lacking. To address this deficit, we examined the P1, N1, P2, and N2, along with their corresponding peak-to-peak complexes, in 10 Wistar rats anesthetized with 1.5–2 % isoflurane in pure oxygen and again after recovery. While under anesthesia, subdermal needle electrodes were inserted and secured for electroencephalographic (EEG) recordings. LLAEPs were assessed during a 20-min, passive, two-tone (500 ms inter-tone interval) paradigm with randomized short (1 s) and long (5 s) inter-pair intervals (IPIs). Overall, while the LLAEP peaks under isoflurane were less defined, they were not eliminated. The peak-to-peak amplitudes, particularly the P1-N1, were significantly smaller under isoflurane than during post-recovery. Our preliminary findings indicate that isoflurane produces global suppression across LLAEP components, presumably reflecting impaired integration of top-down and bottom-up attention and sensory systems under profound sedation with isoflurane.

Considering that packing dielectric materials into the discharge region of a dielectric barrier discharge reactor tends to cause the increase of undesired gas flow resistance and heating effect, herein, we design a combined system (HD-ZnO) of dielectric materials and discharge by integrating a thin ZnO coating into a hybrid discharge (HD) reactor (instead of packing) for effectively synthesizing ozone (O3) from oxygen (O2). Using the thin ZnO coating makes O3 concentration and production yield of HD respectively increased by an average of 28% and 26% with discharge power of 0.4–3.3 W under the optimum conditions, and also avoids the shortcomings of the packing. Discharge diagnosis and physicochemical characterization demonstrate that the enhancement of O3 synthesis in HD-ZnO relative to HD is mainly ascribed to the strong surface reactions catalyzed by the coating in O2 plasma. The catalytic performance of ZnO coating on O3 generation exhibits a good stability during a 4-h uninterrupted test and can be enhanced by reducing the size of ZnO nano-powder and discharge gap of the reactor. Moreover, the designed HD-ZnO possesses a comparable performance with other superior discharge forms on O3 synthesis.

The use of portable oxygen concentrators for preparing an air-based breathing gas can be a good alternative to that of pure oxygen from cylinders in emergency relief. Membrane modules can be used as a gas separation device. In this study, the compressor–vacuum scheme of a portable membrane oxygen concentrator has been analyzed and examined and its choice has been substantiated. An experimental sample with the characteristics of the target stream that meets the requirements of medicine—a flow rate of 6 L/min and an oxygen concentration of 50 vol %—has been developed and tested.

The objective of this study was to evaluate the efficacy of ozonated water for antimicrobial. For evaluated the antibacterial activity, the ozonated water used to investigate against generic E. coli. The ozone generator used in this study was containing electric discharge units, a circulating fan and a cylinder of pure oxygen that was calibrated to release oxygen at 0.5 mg/L per min. after that, the ozonated water produce by bubbled through ozone gas into the distilled water. The concentration of ozonated water measure with the fluorescence light intensity generated by HTA molecules in water solutions. Another that, the antibacterial activity against, the results showed that the antimicrobial activities against of ozonated water high antimicrobial power and a potential for acute generic E. coli

PbSe films deposited by chemical bath deposition (CBD) technology were sensitized in various atmospheres to distinguish the role of iodine and oxygen in the sensitization process. No infrared (IR) photo response was observed in samples sensitized in pure oxygen, showing the O element cannot trigger the infrared response of PbSe. However, a high detectivity of 1 × 1010 was achieved in the sample sensitized in a N2/I2 atmosphere, which demonstrates iodine is a key element for inducing an IR response. The role of iodine was analyzed from the morphological evolution, phase composition transformation and resistance change during the sensitization process. The XRD and FESEM results show a PbI2 3D network forming around the PbSe grains in the sensitization process, playing the role of photo-generated electron transporting channels, which is key to inducing the IR response of PbSe detectors. The 3D network conducting model can explain well the charge separation mechanism of PbSe IR photoconductive detection.

This article shows the possible dangerous effects of the Taldykorgan lead battery plant in Almaty region on the environment and human health.At the same time, protective methods against harmful lead dust emanating from the plant are analyzed by using especially pure oxygen obtained by superionics.

This study investigates the stability of a pure oxygen aeration-activated sludge system for petrochemical wastewater treatment under high organic concentration and non-steady food-to-microorganism (F/M) ratio conditions. Sludge settling characteristics maintained relatively stable conditions with an F/M ratio variation from 0.15 ± 0.04 to 0.33 ± 0.07 kg COD/kg MLSS⋅d, while the excess F/M ratio (0.44 ± 0.16 kg COD/kg MLSS⋅d) resulted in deterioration of the organic removal and sludge-water separation performances. Loosely bound extracellular polymeric substances (EPS) showed more significant effect on sludge settleability than the tightly bound EPS. The genus

A novel approach to produce renewable maleic anhydride (MA) from bio-based platform chemical 5-[(formyloxy)methyl]furfural (FMF) was developed with air or pure oxygen at atmospheric pressure using ...

The results of investigation of the current-voltage characteristics (CVCs) and electron beam generation efficiency in continuous discharges in helium, its mixtures with oxygen and nitrogen, as well as in pure oxygen and helium are presented. Peculiarities of CVCs are singled out and interpreted in terms of a changed role of the principal emission mechanisms with an increase in the voltage. It is shown that a high efficiency of the electron beam generation of more than 80% can be achieved in glow discharges in helium, oxygen, and nitrogen. In helium, it is provided by the predominating photoemission, while in oxygen and nitrogen and their mixtures with helium – mainly by the kinetic emission under the impact of fast heavy particles.

A series of Cy5.5 dye analogs and targeted probes with net charges varied from −3 to 0 were synthesized by an optimized method, followed by comparing their spectral and photostability properties in saturated solutions of air, oxygen, and argon. The Cy5.5 analogs with reduced charge were relatively stable when irridated at their excitation maxima, with a trend of higher stability with lower net charge states. The photostability of dyes was markedly lower in pure oxygen and higher in inert argon relative to ambient atmospheric conditions. The stability of c(RGDyK) conjugates as models of targeted molecular imaging agents mirrored these results and demonstrated the practical utility of the new family of Cy5.5 fluorophores.

Hyperbaric oxygen therapy (HBOT) uses higher atmospheric pressure air or pure oxygen on the human body to facilitate wound healing. Usually, planimetry and oximetry are used in the quantitative evaluation of hyperbaric oxygen therapy effects. However, a noninvasive, quick and easy-to-perform method of evaluation is still required. Thus, the main aim of our study was to assess the usefulness of thermal imaging in evaluating the effects of hyperbaric oxygen therapy on hard-to-heal wounds and to compare these results with that of parameters obtained from planimetry. The studies were performed at the Burn Treatment Center in Siemianowice Slaskie. The study included 60 patients (28 women and 32 men) aged between 48 and 82 who had hard-to-heal wounds localized on their lower extremities. Thermal images were carried out during three stages (I: 0–10 sessions, II: 10–20 sessions and III: more than 20 sessions of HBOT) of the treatment cycle, before entering and after leaving the hyperbaric chamber, respectively. The results showed that the temperature of the regions of interest decreased with the number of completed treatments. Moreover, obtained isotherm area of crura as well as temperature differences between the regions of interest surrounding the wound decreased with the duration of treatment, which suggests an improvement in microcirculation through neovascularization. Our research may lead to planning of a new diagnostic device that uses and correlates several imaging techniques. It seems that the combination of thermal imaging with planimetry can give the physician an additional diagnosis information, as well as information about the effects of therapy at the structural and metabolic level. In addition, both methods are noninvasive, painless, fast and safe, which is very important in the treatment of hard-to-heal wounds.

Hyperbaric oxygen treatment (HBOT) has for centuries been used to improve or cure disorders involving hypoxia and ischemia, by enhancing the amount of dissolved oxygen in the plasma and thereby increasing Oxygen delivery to the tissue. Hyperbaric oxygen therapy (HBOT) involves breathing almost pure oxygen in a special room or small chamber that is pressurized to greater than sea level pressure. Also, wounds and infections that have not responded to other treatment may respond to HBOT by reducing the need of amputation in people with diabetes foot ulcers. The body tissues need oxygen to function and additional oxygen can help damaged tissue heal. Oxygen at high pressure can enhanced tissue functions and fights infection under certain conditions.

Hyperbaric oxygen therapy (HBOT) consists of using of pure oxygen at increased pressure (in general, 2–3 atmospheres) leading to augmented oxygen levels in the blood (Hyperoxemia) and tissue (Hyperoxia). The increased pressure and oxygen bioavailability might be related to a plethora of applications, particularly in hypoxic regions, also exerting antimicrobial, immunomodulatory and angiogenic properties, among others. In this review, we will discuss in detail the physiological relevance of oxygen and the therapeutical basis of HBOT, collecting current indications and underlying mechanisms. Furthermore, potential areas of research will also be examined, including inflammatory and systemic maladies, COVID-19 and cancer. Finally, the adverse effects and contraindications associated with this therapy and future directions of research will be considered. Overall, we encourage further research in this field to extend the possible uses of this procedure. The inclusion of HBOT in future clinical research could be an additional support in the clinical management of multiple pathologies.

As the economical operation of Fuel Cells is essential, in this work, a simulation study is carried out on a 3D geometry of the cathode side of a single-layered Proton Exchange Membrane Fue...

Waterless transportation is a novel method used to keep turbot alive during transportation. In the present study, the effect of atmospheric air or pure oxygen at low temperature on the morphology and several biochemical parameters of living turbot (Psetta maxima) subjected to water-free storage conditions were evaluated. The results of hematoxylin-eosin (HE) staining and scanning electron micrographs indicated that treatment of turbot with pure oxygen for 6 h had no effect on gill silk morphology, and slight shrinkage of the fish gill silks and deformation of the gill filaments were observed 12 h later, relative to the controls (living in the water). In contrast, the atmospheric air treatment induced dramatic alterations in gill structure with a wrinkled surface and narrowed space between gill filaments of the turbot. Furthermore, other biochemical indicators, including of ATP levels, blood glucose levels, cortisol levels and blood urea nitrogen levels, were similarly non-affected by the oxygen treatment, over the course of a 12 h treatment. The data of this study is helpful in understanding fish survival and in providing the theoretical base for improving the live transportation of turbot.

In order to overcome one of the most important disadvantages of the partial oxidation of methane (POX) reaction, which deals with the use of pure oxygen as a gas feed, a mixed metal oxide (MWO 4 , M = Fe, Mn, Ni) is proposed as an oxygen carrier. The aim of this study is to evaluate the feasibility of these tungstates through the use of thermodynamic analyses and process simulations in an arrangement of two reactors. First reactor: CH 4 + MWO 4 = H 2 + CO + M + W; CH 4 + MWO 4 = H 2 + CO 2 + M + W and possibly CH 4 = C + 2H 2 . While in the second reactor: M + W + H 2 O = MWO 4 + H 2 ; C + H 2 O = H 2 + CO; C + 2H 2 O = 2H 2 + CO 2 . Then, the MWO 4 is recycled back to the first reactor to make a continuous process. Simulation results of this process with the different MWO 4 oxides are presented using Aspen Plus © .

Purpose of the article: To determine whether intraoperative ventilation with pure oxygen during the last stage of surgery reduces the occurrence and volume of postoperative pneumocephalus when compared to conventional air/oxygen mixture in patients undergoing craniotomy.prospective randomized single-blinded study to compare the rate of occurrence and volume of postoperative pneumocephalus in patients undergoing craniotomy receiving intraoperative ventilation with pure oxygen (Group B) versus a conventional air/oxygen 1:1 mixture (Group A) during the last stage of surgery. This trial was registered in ClinicalTrials.gov #NCT02722928, protocol number 2015H0032.One hundred patients were randomized into group 'A' and group 'B'. Seventy patients were included in the final analysis with 39 patients allocated in group 'A' and 31 patients in group 'B'. Median and IQR were used for postoperative penumocephalus volume. Group A: 9.65 [3.61-23.20]; Group B: 7.06 [2.70-20.1]. Our study showed no prophylactic effect on postoperative pneumocephalus volume when using mechanical ventilation with higher oxygen concentrations than the standard FiOThe use of intraoperative mechanical ventilation with pure oxygen was not associated with a prophylactic effect on the occurrence and extent of postoperative pneumocephalus in our patient setting. Published literature describing the extent of postoperative pneumocephalus is limited or highly variable among institutions.

Collision-induced absorption between O2 and CO2 molecules associated with the a1Δg (v = 1) ← X3Σ−g (v = 0) band of oxygen around 1060 nm was measured using cavity ring-down spectroscopy. The lineshape for this transition is measured for the first time, and the integrated cross-section is found to be smaller than the only previous report. For pure oxygen, we find an integrated absorption value of (2.10 ± 0.31) × 10−4 cm−2 amg−2 which is in good agreement with the previous reported values. For O2–CO2 collisions we report an integrated value of (6.37 ± 1.09) × 10−5 cm−2 amg−2 which is small but still significant and not accounted for by theory.

PbSe nanocrystals have attracted widespread attention due to a variety of potential applications. However, the practical utility of these nanocrystals has been hindered by their poor air stability, which induces undesired changes in the optical and electronic properties. An understanding of the degradation of PbSe nanocrystals when they are exposed to air is critical for improving the stability and enhancing their applications. Here, we use in situ transmission electron microscopy (TEM) with an environmental cell connected to air to study PbSe nanocrystal degradation triggered by air exposure. We have also conducted a series of complementary studies, including in situ environmental TEM study of PbSe nanocrystals exposed to pure oxygen and PbSe nanocrystals in H2O using a liquid cell, and ex situ experiments, such as O2 plasma treatment and thermal heating of PbSe nanocrystals under different air exposure. Our in situ observations reveal that when PbSe nanocrystals are exposed to air (or oxygen) under elec...

Background: In hyperbaric oxygen therapy (HBOT), a patient is exposed to pure oxygen in a chamber. While HBOT is a long-standing and well-established treatment for a wide variety of medical conditions, one of the main complications is middle ear barotrauma (MEB), which can lead to complaints of ear discomfort, stuffiness or fullness in the ear, and difficulties in equalizing ear pressure. The aim of this study is to evaluate the efficacy of self-acupressure in preventing and reducing the degree of MEB associated with HBOT. Methods: This is a prospective nonrandomized controlled study. A sample of 152 participants will be assigned to 2 groups in a 1:1 ratio. The participants in the control group will receive conventional Valsalva and Toynbee maneuvers, while those in the experimental group will be given additional self-acupressure therapy. The acupoints used will be TE17 (Yifeng), TE21 (Ermen), SI19 (Tinggong), and GB2 (Tinghui). The Modified Teed Classification, symptoms of MEB, and overall ear discomfort levels will be assessed. Data will be analyzed using the Chi-Squared test or t test. Objectives: This study aims to evaluate the efficacy of self-acupressure for preventing and reducing the degree of MEB associated with HBOT. Trial registration: ClinicalTrials.gov Identifier: NCT04311437. Registered on 17 March, 2020.

IGFC based on high temperature SOFC coupled with CO2 capture process provides a new technology route of high efficiency and nearly zero CO2 emission power system. Flame burning is an ideal method for tail gas treatment. In this paper, an oxy-combustor for a 10kW IGFC system anode exhaust gas is experimentally and numerically studied. Simulation method is verified by experiments. Key performances of the combustor are studied under different system process design conditions. 315K might be an ideal condensation temperature before burning for flame stability. CO could be almost fully converted under flame burning condition.CO2 concentration after burning is over 0.958 when excess O2 is less than 5%. Overall, 5% excess O2 could be recommended for environmental consideration. An optimal tangential angle exists around 25°for liner temperature controlling. Systems with anode cycling might release less CO pollutant in theory for no addition of extra H2O. Total fuel utilization percent had better be high enough to make oxygen flame temperature of anode exhaust gas lower than 1800K to make systems environment friendly. The results would be of great value to IGFC and CO2 capture combined system designing.

Background Currently, methods for identifying the intersegmental plane during anatomical segmentectomy can be classified into 2 categories: the bronchial method and the vascular method. One of the vascular methods, the arterial-ligation-alone method, has not yet been validated or objectively evaluated in a large case series. We thus aimed to confirm that the arterial-ligation-alone method could effectively and accurately identify the intersegmental plane. Methods We retrospectively reviewed the records of 104 patients who were scheduled for thoracoscopic anatomic segmentectomy. Preoperative three-dimensional (3D) reconstruction was performed on all the affected lungs to distinguish the targeted segmental arteries, veins and bronchi. The procedure was as follows: first, based on the 3D reconstruction of the lung, the targeted segmental arteries were distinguished and ligated. Second, bilateral pulmonary ventilation was performed with pure oxygen. When the affected lung had completely inflated, contralateral pulmonary ventilation was performed. After waiting for some time, the first intersegmental plane could be obtained, and the time was recorded as T1, with an electric coagulation hook being used for marking. Thirdly, when the targeted segmental veins and bronchi had been ligated, the second intersegmental plane could be obtained by the inflation-deflation method as before, with the waiting time being recorded as T2. The differences between the 2 intersegmental planes were evaluated by 2 experienced chief thoracic surgeons. Result In a total of 99 (95.2%) patients, the intersegmental planes were successfully and accurately identified by the arterial-ligation-alone method. Ultimately, 85 (81.7%) patients underwent thoracoscopic anatomic segmentectomy. The results for evaluating the differences between the 2 planes were as follows: completely consistent (94 cases, 94.9%), basically consistent (5 cases, 5.1%), and discrepant (0 cases, 0%). The mean T1 was 13.6±2.7 minutes (range, 8-25 minutes), and the mean T2 was 13.0±2.6 minutes (range, 8-23 minutes), with P=0.100 (95% CI). For 99 patients, the mean nodule size was 1.1±0.34 cm. In the 85 patients who underwent segmentectomy, the mean margin width was 2.84±0.51 cm, the mean operative duration was 165.6±18.3 minutes, the mean operative hemorrhage was 52.1±20.2 mL, and the mean duration of chest tube drainage was 3.9±1.3 days. Postoperative complications related to operative procedures occurred in 2 cases. Conclusions The arterial-ligation-only method can effectively, accurately and inexpensively identify the intersegmental plane, and is especially suitable for the patients whose veins or bronchi are difficult to anatomize. Whether the target bronchus is ligated has no effect on the intersegmental plane.

In the present study, we performed measurements of threshold intensities for laser spark ignition of air/fuel mixtures and laser breakdown in pure oxygen. The slight laser wavelength variations near 760 nm did not lead to noticeable changes in threshold intensities in pure O2. In addition, the high temperature experiments (up to 1000 K) did not reveal the dependence of threshold intensity on temperature.

In aerobic wastewater treatment, aeration is the most critical element of the treatment system. It supplies microorganisms with the required amount of dissolved oxygen, maintains solids in suspension and controls membrane fouling, where needed. However, conventional activated sludge, where air is used, is limited to low-strength wastewaters as higher loadings or more intense feeds require both higher biomass and dissolved oxygen concentrations. In membrane bioreactors, despite being able to operate at higher biomass concentrations, their operation at high biomass concentrations and high organic loadings has not been tested. By replacing air with pure oxygen, oxygen transfer rates increase at lower flowrates. In this work, the potential and limitations of pure oxygen systems over conventional ones are reviewed. Also, the effect of the operational parameters or the mixed liquor characteristics on oxygen transfer is determined. Pure oxygen affects bacterial structure, controls foam formation, improves bacterial enzymatic activity and, in membrane bioreactors, leads to a better recovery of permeability after cleanings. It treats much higher loadings without compromising final effluent quality. Fine bubbles are more efficient in oxygen transfer due to their increased contact area. Nevertheless, pure oxygen aeration at times is not essential or it may generate effluent organic matter of a higher refractory character. We then recommend that it be used to applications where conventional aeration is not adequate.