oxygen

摘要： Water represents a critical nutrient, the absence of which will be lethal within days. Water’s importance for the prevention of nutrition-related noncommunicable diseases has received more attention recently. There are major gaps in knowledge related to the measurement of total fluid intake and hydration status at the population level. It is poorly understood the effects of chronic mild dehydration and fluid consumption on specific health outcomes including obesity. Urolithiasis is the only disorder that has been consistently associated with chronic low daily water intake. Water is an essential nutrient required for life, but until now, it was considered mainly as a universal solvent, which served to prepare the broth of life inside the cells, but the function of water now takes unusual importance with our discovery of the unsuspected ability of the human body to transform the power of light into chemical energy by dissociating the molecule from water, as it happens in plants. The process that we replicated in the laboratory for the first time in 2007, represents a light at the end of the tunnel, in the growing and serious problem of contamination of the mysterious and vital liquid that we call water.

摘要： Background: Oxygen is a commonly used drug in modern medical care. It has biochemical actions, safe dosage ranges, adverse physiologic effects and can be toxic at high doses and prolonged use. As a drug, it needs a formal prescription prior to administration. The prescription needs to meet certain basic minimums for appropriateness and safety. Objectives: The aim of the study was to assess the standards of prescriptions for oxygen therapy amongst admitted medical patients at the Dr. George Mukhari Academic Hospital. Materials and Methods: It was a cross-sectional study of 159 acutely ill medical admissions who received supplemental oxygen. The medication charts of patients on oxygen were audited;with regards to the availability and/or adequacy of the prescription for oxygen. Results: Of the one hundred and fifty nine patients on oxygen only 43 (27%) had an actual prescription for oxygen written. The target oxygen saturation was specified in 19 (44%) cases. The device for oxygen delivery was specified in 21 (49%) patients and just over half of the patients (56%) had flow rates indicated on their charts. Conclusion: The practice of oxygen administration in our medical wards was sub-optimal. The audit highlights the need for education and training in acute oxygen therapy.

摘要： The coronavirus disease 2019 pandemic had deleterious effects on the healthcare systems around the world.To increase intensive care units(ICUs)bed capacities,multiple adaptations had to be made to increase surge capacity.In this editorial,we demonstrate the changes made by an ICU of a midwest community hospital in the United States.These changes included moving patients that used to be managed in the ICU to progressive care units,such as patients requiring noninvasive ventilation and high flow nasal cannula,ST-elevation myocardial infarction patients,and post-neurosurgery patients.Additionally,newer tactics were applied to the processes of assessing oxygen supply and demand,patient care rounds,and post-ICU monitoring.

摘要： The accumulation of oxygen is one of the most important characteristics that distinguish Earth from other planets in the solar system,which is also considered to be the key factor influencing the birth and evolution of complex life forms.The oxygenation process of the Earth surface has long been viewed to be episodic with two critical intervals occurring in the early Paleoproterozoic(2.45-2.10 Ga)and the late Neoproterozoic(0.80-0.54 Ga),with a 1.3-billion-year-long low oxygen period in between.Recently,increasing independent works carried out by different scientific teams in the Yanliao Basin,North China are demonstrating that the atmospheric oxygen concentrations had reached>4%PAL(present atmospheric levels)at least during 1.59-1.56,1.44-1.43,and 1.40-1.36 Ga.These estimated values are higher than the previously recommended values of<0.1-1%PAL.Such a scenario discovered in the Yanliao Basin is consistent with the synchronously deposited strata in Australia and Siberia,pointing to a Mesoproterozoic oxygenation event(1.59-1.36 Ga)between the two major oxygenation intervals during the Proterozoic.This Mesoproterozoic oxygenation event is coupled with the break-up of the Columbia(Nuna)supercontinent,the formation of organic-rich shales and Fe-Mn deposits,and the early innovation of eukaryotic algae,indicating that the geological and biological co-evolutionary processes control the Earth surface system.

摘要： The vital role of anthocyanins in Hibiscus sabdariffa L. is now known to most consumers. The richness of anthocyanins in antioxidants, vitamin C, minerals, etc., provides Hibiscus juice with proven nutritional qualities. The health requirements of recent years have made food products with added preservatives or processed at high temperatures less popular, thus explaining the new orientations towards innovative and interdisciplinary technologies. Anthocyanins from Hibiscus sabdariffa L. are, however, sensitive to degradation factors such as temperature, light, enzymes and also oxygen. The instability of anthocyanins has long been a subject of research using classic techniques such as heat treatment, the results of which are often limited by the rapid degradation and above all the destruction of the nutritional and organoleptic qualities of the product. Oxygen dissolved in juices is so far treated by bubbling with an inert gas or by adding other molecules such as preservatives which can cause a lot of health damage. The electrochemical approach is a new stabilisation technique that reduces the dissolved oxygen in the juice, cold and without the addition of other molecules. The electrolysis of Hibiscus juice was carried out by noble electrodes (Platinum and Stainless Steel) with a well-characterised Time/Potential or Time/Intensity couple. The electroreduced samples and the control were then stored at 4°C, 25°C and 37°C for more than 6 months. Monitoring of anthocyanins in the first month, of the samples and the control, showed a significant difference of 10% between the electroreduced extract and the untreated control at 37°C, which had previously been problematic for the heat treatment and even for the other membrane techniques. Oxygen reduction on the platinum electrode/ECS allowed the retention of more than 10% of anthocyanins after 4 weeks of storage at 25°C and 37°C. At 4°C, a significant difference of 5% between the electro-reduced Hibiscus juice and the control was maintained until the fifth month of storage with the 1/5 ratio (calyx/water). Non-significant losses in anthocyanin (10 mg/l), for the juice with reduced dissolved oxygen, were noted for the 1/5 and 1/15 ratios during the first month of storage at 4°C against 24 mg/l of significant losses for the 1/20 ratio. However, the untreated control showed significant losses for the ratios 1/20, 1/15 and 1/5. Oxygen dissolved in the juice therefore considerably degrades the anthocyanins of Hibiscus sabdariffa L. from the first month of storage at 4°C.

摘要： Objective Fluid inclusions are microscopic fluids entrapped in mineral lattice defects or cavities within the host minerals that can keep a record of physical and chemical information during the process of mineral crystallization,which can be sealed in through geological time.

摘要： Pt-based alloy nanowires are promising oxygen reduction reaction(ORR)catalysts.It is widely accepted that intermetallic Pt-based alloys with face-centered tetragonal(fct)structure are more stable than corresponding disordered Pt-based alloys with face-centered cubic(fcc)structure.However,nanowires are unstable under high temperatures.The synthesis of fct-phase Pt-based nanowires under the phase transformation process remains a significant challenge.

摘要： A science teacher tells his class,"Oxygen is a must for breathing and life.It was discovered in 1773."A student responds,"Thank God I was born after 1773!Otherwise I would have died without it."

摘要： The development of advanced transition metal/nitrogen/carbon-based(M/N/C)catalysts with high activity and extended durability for oxygen reduction reaction(ORR)is critical for platinum-group-metal(PGM)free fuel cells but still remains great challenging.In this review,we summarize the recent progress in two typical M/N/C catalysts(atomically dispersed metal-nitrogen-carbon(M-N-C)catalysts and carbon-supported metal nanoparticles with N-doped carbon shells(M@NC))with an emphasis on their potential applications in fuel cells.Starting with understanding the active sites in these two types of catalysts,the representative innovative strategies for enhancing their intrinsic activity and increasing the density of these sites are systematically introduced.The synergistic effects of M-N-C and M@NC are subsequently discussed for those M/N/C catalysts combining both of them.To translate the material-level catalyst performance into high-performance devices,we also include the recent progress in engineering the porous structure and durability of M/N/C catalysts towards efficient performance in fuel cell devices.From the viewpoint of industrial applications,the scale-up cost-effective synthesis of M/N/C catalysts has been lastly briefed.With this knowledge,the challenges and perspectives in designing advanced M/N/C catalysts for potential PGM-free fuel cells are proposed.

摘要： BACKGROUND Non-alcoholic fatty liver disease(NAFLD) is a common cause of liver disease worldwide and is a growing epidemic. A high ratio of omega-6 fatty acids to omega-3 fatty acids in the diet has been implicated in the development of NAFLD. However, the inflicted cellular pathology remains unknown. A high ratio may promote lipogenic pathways and contribute to reactive oxygen species(ROS)-mediated damage, perhaps leading to mitochondrial dysfunction.Therefore, these parameters were investigated to understand their contribution to NAFLD development.AIM To examine the effect of increasing ratios of omega-6:3 fatty acids on mitochondrial function and lipid metabolism mediators.METHODS Hep G2-derived VL-17 A cells were treated with normal(1:1, 4:1) and high(15:1,25:1) ratios of omega-6: omega-3 fatty acids [arachidonic acid(AA):docosahexaenoic acid(DHA)] at various time points. Mitochondrial activity and function were examined via MTT assay and Seahorse XF24 analyzer, respectively.Triglyceride accumulation was determined by using Enzy Chrom? and levels of ROS were measured by fluorescence intensity. Protein expression of the mediators of lipogenic, lipolytic and endocannabinoid pathways was assessed by Western blotting.RESULTS High AA:DHA ratio decreased mitochondrial activity(P < 0.01;up to 80%) and promoted intracellular triglyceride accumulation(P < 0.05;40%-70%).Mechanistically, it altered the mediators of lipid metabolism;increased the expression of stearoyl-Co A desaturase(P < 0.05;22%-35%), decreased the expression of peroxisome proliferator-activated receptor-alpha(P < 0.05;30%-40%) and increased the expression of cannabinoid receptor 1(P < 0.05;31%).Furthermore, the high ratio increased ROS production(P < 0.01;74%-115%) and reduced mitochondrial respiratory functions such as basal and maximal respiration, ATP production, spare respiratory capacity and proton leak(P < 0.01;35%-68%).CONCLUSION High AA:DHA ratio induced triglyceride accumulation, increased oxidative stress and disrupted mitochondrial functions. Stimulation of lipogenic and steroidal transcription factors may partly mediate these effects and contribute to NAFLD development.