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In this study a comprehensive analysis of the influence of synthesis route of CuFe 2 O 4 spinel mixed oxides on their catalytic performance in the N 2 O decomposition was carried out. A co-precipitation technique allowed one to obtain the CuFe 2 O 4 spinel with a higher specific surface area and pore volume compared to the synthesis with the application of organic additives. This resulted in better catalytic performance of the CuFe 2 O 4 samples prepared by co-precipitation. The microwave activation step with the duration of 1 min during the co-precipitation synthesis led to the formation of the CuFe 2 O 4 spinel with a higher content of oxygen vacancies per 1 m2 in comparison with the sample obtained without the microwave activation. This fact caused a significantly higher specific activity of the CuFe 2 O 4 spinel synthesized with the application of 1 min microwave activation. The increase of the microwave treatment time led to the fast growth of the contents of the CuO and α-Fe 2 O 3 phases, which are less active in the N 2 O decomposition, resulting in the activity drop. [Display omitted] [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) and biomass are recognised as renewable energy carriers with substantial promise for reducing carbon emissions. However, the issue of nitrogen oxides (NO X , including NO and NO 2) and nitrous oxide (N 2 O) emissions from ammonia combustion and soot from biomass combustion, remains a pressing concern due to their detrimental impacts on the environment and human health. This study investigated the mechanism of pollutant formation during ammonia-lignin co-firing through reactive molecular dynamics (RMD) simulations. The results indicate that co-firing a certain amount of ammonia with lignin can reduce the formation of soot. This is mainly due to NH 2 radicals converting a portion of polycyclic aromatic hydrocarbon (PAH) precursors into C–N compounds. However, it is necessary to maintain higher ammonia concentrations. Adding a small quantity of ammonia would decrease the extent of oxidative reactions within the system and fail to generate enough NH 2 radicals to consume the carbon atoms forming PAH precursors, ultimately resulting in increased soot production. The impact of lignin on the formation of NO X and N 2 O during ammonia combustion has two main aspects: Firstly, the oxidising radicals formed during the initial decomposition of lignin promote the generation of N–O bonds, leading to an increase in the quantities of NO X and N 2 O during the initial reaction stage. Secondly, the carbon-containing products produced from lignin decomposition consume nitrogen atoms by forming N–C bonds, thereby diminishing available nitrogen atoms for nitrogen oxides formation. This study provides new insights into the formation of primary pollutants of ammonia and biomass co-firing on an atomic scale, which can help develop pollutant mitigation measures. • The chemical mechanism of pollutant formation during the co-firing of ammonia and biomass lignin is revealed. • A small quantity of ammonia promotes soot formation but increased quantities have the opposite effect. • NO production is enhanced by lignin in the initial stage of the co-firing, but the trend is reversed subsequently. • NO 2 formation is linked to oxidative reactions, while N 2 O formation depends on NH 2 concentration. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Controlled studies have extensively documented that concentrate supplements typically increase enteric CH 4 emissions and milk yield and reduce emissions per unit of milk produced and dry matter intake. However, no studies have been conducted to determine the effect of concentrate on predicted greenhouse gas emissions from dairy farms representing the Australian pasture-based farming system. Thus, this study sought to determine how dietary concentrate supplementation affects enteric and manure CH 4 , and N 2 O of Australian pasture-based dairy farms. The Australian Dairy Carbon Calculator was used, which incorporates emission factors and methodologies used in the National Greenhouse Gas Inventory as reported to the Intergovernmental Panel on Climate Change. Primary data were collected and analyzed from 120 commercial farms in Australia's major dairy regions. Then the farms were divided into 4 groups based on their dietary concentrate supplementation: ≤1 (low; 15 farms), 1 to 2 (moderate; 35 farms), 2 to 3 (high; 35 farms), and ≥3 (very high; 35 farms) t of concentrate dry matter (tDM) per cow per year. Sources of greenhouse gas emissions were CO 2 from concentrate production, enteric CH 4 , and manure CH 4 and N 2 O. Total dry matter intake, milk yield, and daily enteric CH 4 production (g/d) quadratically increased with concentrate level, whereas greenhouse gas emission intensity of milk production (kg of CO 2 equivalent per kg of fat- and protein-corrected milk) decreased by 14% for farms supplementing with ≥3 tDM/cow per year compared with those supplementing with ≤1 tDM/cow per year of dietary concentrate. The N 2 O and CH 4 emissions from manure increased quadratically and linearly, respectively, with the increasing supplementation of concentrate. Farms supplementing 2 to 3 tDM/cow per year showed substantial increases in gross income, gross margin, earnings before interest and tax, and net income ($/cow per year) compared with those supplementing of ≤1, 1 to 2, and ≥3 tDM/cow per year. Overall, increasing dietary concentrate supplementation for dairy cows resulted in increased milk production per cow, reduced greenhouse gas emissions per unit of milk produced, and increased income and profit. However, a comprehensive life cycle assessment study is needed to account for carbon sequestration by other farm components, such as pastures and trees, which were not considered in the present study. In addition, the present study was based on modeling and did not gather ground truth information for DMI, digestibility, crude protein, and urinary and fecal N excretion. Therefore, data should be interpreted with caution, and studies gathering such information are encouraged. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N 2 O) emissions sourced from agricultural and industrial activities have gained much attention because of their contribution to the global greenhouse effect and ozone layer depletion. Significant efforts have been devoted to developing the cost-effective and highly efficient technologies for N 2 O removal. The direct N 2 O decomposition is limited by the thermodynamic equilibrium at high temperatures. Recently, catalytic reduction of N 2 O with carbon-free hydrogen derived from in situ ammonia decomposition is considered as an ideal approach. Herein, thermal decomposition of N 2 O is investigated by employing a BaCe 0.85 Fe 0.15 O 3-δ -BaCe 0.15 Fe 0.85 O 3-δ (BCF8515-BCF1585) hydrogen-transporting membrane or a Ce 0.85 Sm 0.15 O 1.925 -Sm 0.6 Sr 0.4 FeO 3-δ (SDC-SSF) oxygen-transporting membrane respectively. It is noted that the membrane catalysis of N 2 O decomposition by reacting with permeated hydrogen or via in-situ oxygen removal displayed significant advantages over the direct thermal decomposition of N 2 O under a fixed bed condition. Moreover, the N 2 O conversion as well as hydrogen/oxygen permeability of such membranes were greatly improved by the introduction of porous Ni–CeO 2 or SDC-NCO layers due to the increased catalytic activities and hydrogen/oxygen surface exchange kinetics. [ABSTRACT FROM AUTHOR]

[Display omitted] • The deviation of N 2 O emission factor (EF) from short-term monitoring can reach 20%. • The N 2 O EF for sludge incineration in China may be smaller than the default value. • The N 2 O EF decreases as the temperature in the furnace increases. • The N 2 O EF of the sludge incinerators with smaller heat loads fluctuates more. • The fluctuation range of the N 2 O EF narrows with the increase of temperature. The N 2 O emissions resulting from sludge incineration are estimated using the default values published by the Intergovernmental Panel on Climate Change (IPCC), which may differ significantly from the actual emissions. In this investigation, N 2 O emissions from four sludge incineration lines in two plants were monitored for varying durations. The variation in N 2 O emission factors (EFs) between incineration lines of the same plant was much smaller than the difference between different plants. Data on N 2 O EFs obtained from brief monitoring may contain variabilities of up to 30%. N 2 O EFs were more sensitive to temperature changes at low temperatures, necessitating extended monitoring periods to improve the reliability of N 2 O monitoring outcomes in cases of low furnace temperatures. Excessive use of the SNCR system to reduce NOx emissions resulted in concentrations of N 2 O and NH 3 in the exhaust gases exceeding NOx levels. In the case of furnace temperature control and advanced reburning technology, it is advisable to utilize actual monitoring data or the smaller default values provided by the IPCC in China. Otherwise, the estimated N 2 O emissions may exceed the actual emissions. [ABSTRACT FROM AUTHOR]

• Understanding the dynamics of N 2 O and CH 4 fluxes avoids emissions during storage. • Manure discharge release significant N 2 O and CH 4 emissions due to feed inefficiency. • Shortening manure storage is the most viable management at smallholder dairy farms. • Trade-offs between reducing CH 4 or N 2 O fluxes often appears in manure management. Storing manure emits greenhouse gas (GHG) emissions, including nitrous oxide (N 2 O) and methane (CH 4). However, the emissions from types of manure stored at smallholder dairy farms remains unknown. Hence, the study aims to analyse the dynamics of N 2 O and CH 4 from different types of dairy manure as affected by storage periods. We collected samples from fresh manure (FM-DF1), manure from communal ponds in an urban dairy farm (IP-DF1, FP-DF1, MS-DF1), fresh manure from an urban dairy farm (FM-DF2), and fresh (FM-DF3), separated (FS-DF3), and fermented manure (FR-DF3) from a peri -urban dairy farm, and stored them for eight weeks and analyse them using the closed chamber method. The changes of manure composition including total solids (TS), nitrogen (N), ammonia–nitrogen (N-NH 3), and carbon (C) were analysed. Results indicated an increase TS in all treatments except for MS-DF1, while N, N-NH 3 , and C content decreased in all treatments. The N 2 O emissions formed at the start, peaked in the middle, and declined towards the end storage period. The CH 4 emissions peaked at the start and decreased until the end storage period. Treatment FM-DF2 yield highest cumulative of N 2 O (0.82 g/m2) and CH 4 (41.63 g/m2) compared to other fresh manure treatment. A mixed model analysis detected a significant interaction (p < 0.05) between manure types and storage periods. In conclusion, manure types and storage periods affect the emissions. Changes in manure concentration during storage and animal diets are two important factors influencing emissions. Strategies to reduce emissions include reducing moisture content in manure, shortening storage periods, and improving feed quality. [ABSTRACT FROM AUTHOR]

Pediatric patients undergoing minor, but painful procedures in an Emergency Department (ED) need adequate relief of pain and distress to prevent long term negative effects and adversely impact procedures. Inhaled nitrous oxide (N 2 O) is a needle-free pain management option. We conducted a systematic review to determine whether N 2 O is as effective as local anesthesia in minor procedures. The purpose of this study was to evaluate available evidence regarding analgesic effectiveness of N 2 O in pediatric patients. We searched MEDLINE, Embase, Cochrane and Cinahl databases for controlled trials published in English with pediatric patients in an ED treated with N 2 O compared to local anesthesia and with pain as primary outcome. Adverse events was one of the secondary outcomes. The GRADE system was used to rate the overall quality of evidence. We included seven studies with a total of 371 patients. Two studies showed N 2 O was equally effective in pain treatment as local anesthesia. Five studies showed N 2 O combined with local anesthesia is more effective in reducing pain than local anesthesia alone. None of the included studies reported major adverse effects. The quality of evidence is low. N 2 O can have an important contribution in pain management, but should be combined with local anesthesia for optimal pain management in pediatric patients undergoing minor, but painful procedures in an ED. IV. • What is Known Pain management in pediatrics patients undergoing minor, but painful procedures in an ED is important to prevent long term negative effects and adversely impact procedures. • What is New Nitrous oxide is a safe and effective method for pain management but should be combined with local anesthesia for a maximum analgesic effect. [ABSTRACT FROM AUTHOR]

• Vertical column density and column averaged dry air concentrations of GHGs were retrieved from FTIR using GFIT model. • Seasonal and interannual variations of GHGs were studied. • FTIR retrieved X CO 2 and X CO data were compared with satellite data. Solar absorption spectra collected using a ground-based Fourier Transform Infrared (FTIR) Spectrometer were used to retrieve the column-averaged concentrations (X) of CO 2 , CH 4 , CO, and N 2 O during the years 2016–2019 in the Suburban region of Shadnagar, Telangana, India. For the research period, the diurnal mean amplitudes of X CO 2 , X CH 4 , X CO, and X N 2 O are ∼ 13 ppmv, ∼50 ppbv, ∼13 ppbv, and ∼ 19 ppbv respectively. Strong seasonality at the study site is indicated by the seasonal variations of X CO 2 and X CO of 18.3 ppmv and 39.2 ppbv, respectively. Additionally, we compared FTIR data to X CO 2 detected by Orbiting Carbon Observatory-2 (OCO-2) and CO columns from Measurements of Pollution in the Troposphere (MOPITT). For the X CO 2 and CO columns, the comparison research shows a mean relative bias between FTIR data and satellite data of 0.92 % and 0.71 %, respectively. The FTIR and satellite data show a Pearson correlation coefficient (r) of 0.71 (X CO 2 , N = 26 co-located) and 0.60 (CO columns, N = 44), respectively. The findings demonstrate a good agreement between our data and satellite data. [ABSTRACT FROM AUTHOR]

While ammonia (NH 3) and hydrogen (H 2) are promising carbon-free fuels, there are significant challenges presented by their combustion properties. Blending them can help mitigate some of these issues; however, the fundamental behaviors of these blends need to be well understood. A constant volume combustion chamber (CVCC) is used to study the emissions of nitrogen oxides (NO, NO 2 , N 2 O), laminar burning velocity (LBV), and intrinsic instabilities for H 2 -NH 3 blends across a wide range of equivalence ratios (Φ = 0.5 to 1.5) and volume fractions of H 2 in the blends (0% to 50%). Measurements of LBV are consistent with existing data where available. The largest NO x and N 2 O emissions are found at lean conditions and decrease significantly for rich mixtures. NO x emissions tend to increase with H 2 fractions in fuel for lean mixtures. Intrinsic instabilities are more prominent at lean conditions and heavily influenced by the amount of H 2 in the blend. [Display omitted] • NO x production peaks at Φ =0.7, increases with H 2 content for lean mixtures. • N 2 O production peaks at lowest Φ , no significant variation with H 2 content. • Higher H 2 content results in earlier and more pronounced flame wrinkling. • LBV and emissions data extends available range for mechanism validation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acidification, coverage, microbe N conversion, adsorption combined for NH 3 reduction. • Rich H 2 SO 4 and sulfate remained on the vermiculite (VM) after 5 M H+ modification. • Giant CO 2 bubbles due to initial slurry acidification promoted the cover floating. • Vermiculite after 5 M H+ modification performed highest NH 3 reduction (68 %). • NH 4 +/ NH 3 adsorption by VM contributed little (4.7%) to the overall NH 3 mitigation. Animal slurry storage is an important ammonia (NH 3) emission source. Sulfuric acid (H 2 SO 4)-modified vermiculite coverage is a new promising technology for controlling NH 3 emission from slurry storage. However, the underlying mechanisms in controlling the mitigation effect remain unclear. Here, a series of experiments to determine the effect of H 2 SO 4 on the modified vermiculite properties, floating persistence, and NH 3 mitigation effect was conducted. Results showed that abundant H 2 SO 4 and sulfate remained on the outer surface and in the extended inner pores of the vermiculite with acidifying H+ concentrations higher than 5 M. An initial strong instantaneous acidification of surface slurry released rich carbon dioxide bubbles, strengthening cover floating performance. An acidification in the vermiculite cover layer and a good coverage inhibition interacted, being the two leading mechanisms for mitigating NH 3 during initial 40–50 days of storage. The bacterial-amoA gene dominated the conversion of NH 3 to nitrous oxide after 50 days of storage. Vermiculite with 5 M H+ modification reduced the NH 3 emissions by 90 % within the first month of slurry storage and achieved a 64 % mitigation efficiency throughout the 84 days period. With the development of the aerial spraying equipment such as agricultural drones, acidifying vermiculite coverage hold promise as an effective method for reducing NH 3 emission while absorbing nutrients from liquid slurry storage tank or lagoon. This design should now be tested under field conditions. [ABSTRACT FROM AUTHOR]

• Community composting was systematically studied in terms of atmospheric emissions. • Ammonia, methane, nitrous oxide, VOC and odours were measured in several sites. • Community compost presents a good quality, especially in terms of stability. • VOC families were diverse, although terpenes were the predominant compounds. • The age of the material and turning dramatically affects gaseous emissions. Composting has demonstrated to be an effective and sustainable technology to valorise organic waste in the framework of circular economy, especially for biowaste. Composting can be performed in various technological options, from full-scale plants to community or even individual composters. However, there is scarce scientific information about the potential impact of community composting referred to gaseous emissions. This work examines the emissions of methane and nitrous oxide as main GHG, ammonia, VOC and odours from different active community composting sites placed in Spain, treating kitchen, leftovers and household biowaste. Expectedly, the gaseous emissions have an evident relation with the composting progress, represented mainly by its decrease as temperature or biological activity decreases. GHG and odour emission rates ranged from 5.3 to 815.2 mg CO 2eq d-1 kg-1VS and from 69.8 to 1088.5 ou d-1 kg-1VS, respectively, generally being lower than those find in open-air full-scale composting. VOC characterization from the community composting gaseous emissions showed a higher VOC families' distribution in the emissions from initial composting phases, even though terpenes such as limonene, α-pinene and β-pinene were the most abundant VOC along the composting process occurring in the different sites studied. The results presented in this study can be the basis to evaluate systematically and scientifically the numerous current projects for a worldwide community composting implementation in decentralised biowaste management schemes. [ABSTRACT FROM AUTHOR]

This paper explores the relevance of a new class of upper stages commonly referred to as Orbital Transfer Vehicles (OTVs) or Kick-Stages, and the importance of green propellants in the development of such systems. Orbital Transfer Vehicles are currently developed for diverse applications by many entities and are expected to have a major impact in the future of space missions and overall space sector. Such systems are commonly connected to the topic of On-Orbit Servicing with the promise of unlocking new missions, including active space debris removal, multi-payload to multi-orbit delivery, in-orbit experiments, in-orbit refuelling and other generic services. Green propulsion is an increasingly prevalent trend in the space industry that has experienced significant growth in recent decades with the main objective of identifying suitable alternatives to commonly used, toxic liquid propellants for in-space applications. The study investigates the synergies between the two themes, underlining the advantages that a widespread use of green technologies could bring to the overall sector, but also examining the final benefits to the system design of OTVs. Due to the numerous and challenging propulsive system requirements associated with these systems, green technologies are analysed to determine their advantages and disadvantages in comparison with current concepts, outlining current trends and expected future developments. The focus is on attainable performances of propulsion systems with respect to the required dry and inert mass. Various architectures of the different green alternatives based on hydrogen peroxide and the more peculiar self-pressurized propellants are proposed, exploring green propellants-based designs that can offer synergies and advantages over classical ones. These new architectures offer performance comparable to classical and widely available toxic alternatives and present the important advantage of using easy-to-handle propellants. The development of such new options has the potential to enable innovative future designs by improving mass and size requirements of new propulsion systems, thereby enhancing the current landscape. • Orbital Transfer Vehicles are emerging in the space sector as enabling technology. • The propulsion systems of Orbital Transfer Vehicles are crucial for the success of their missions. • Green Propellants offer various synergies possibly advantageous for new OTV designs. • Green Propellants perform well against toxic alternatives, but have less heritage. • Multiple design choices based on green propellants are proposed and compared. [ABSTRACT FROM AUTHOR]

Small rhizosphere exudates as chemical signals provide a green strategy to reduce nitrogen emissions and promote low-carbon agriculture. Specific biological nitrification inhibitors (BNIs) and biological denitrification inhibitors (BDIs) could retard nitrification and denitrification, thus reducing N 2 O emissions from terrestrial ecosystems. Enhanced nitrogen removal rates and lower N 2 O emissions are achieved by biological denitrification promoters (BDPs), such as root-derived fatty acid amides and sterols, and microbe-derived N -acyl-homoserine lactones (AHLs) in aquatic environments. Cultivating BNI/BDI/BDP-enhanced plant varieties, intercropping and rotation with BNI/BDI plants, developing green nitrogen fertilizers, and designing water purification bioagents based on small rhizosphere exudates are promising application measures for supporting green low-carbon agriculture. Low-carbon approaches to agriculture constitute a pivotal measure to address the challenge of global climate change. In agroecosystems, rhizosphere exudates are significantly involved in regulating the nitrogen (N) cycle and facilitating belowground chemical communication between plants and soil microbes to reduce direct and indirect emissions of greenhouse gases (GHGs) and control N runoff from cultivated sites into natural water bodies. Here, we discuss specific rhizosphere exudates from plants and microorganisms and the mechanisms by which they reduce N loss and subsequent N pollution in terrestrial and aquatic environments, including biological nitrification inhibitors (BNIs), biological denitrification inhibitors (BDIs), and biological denitrification promoters (BDPs). We also highlight promising application scenarios and challenges in relation to rhizosphere exudates in terrestrial and aquatic environments. [ABSTRACT FROM AUTHOR]

General anaesthesia is in common use for patients undergoing surgical procedures, with the option of both inhalational and intravenous anaesthetic techniques. Anaesthetic gases are often excluded from discussions on sustainable healthcare delivery, despite being a significant contributor to the overall environmental impact of healthcare services. A literature review was carried out on previously published papers on the impact anaesthetic gases have on our environment and at ways to reduce their impact in current anaesthetic practice. The aim was to write a narrative review detailing the areas of concern as well as the current clinical situation in the European setting. The two classes of inhaled anaesthetic agent most frequently used are nitrous oxide and volatile agents (most commonly sevoflurane, isoflurane and desflurane). Both are recognised greenhouse gases that contribute to climate change. Minor modifications in the use of anaesthetic gases can have a significant environmental impact. These modifications include avoiding nitrous oxide whenever possible, avoiding desflurane (and using sevoflurane instead), using low flow anaesthesia during maintenance, swapping volatile-based anaesthesia for a TIVA technique when clinically appropriate and considering the use of central neuraxial or regional anaesthesia in place of general anaesthesia when possible. • Anaesthetic gases include volatile agents and nitrous oxide, both known greenhouse gases • The most common volatile anaesthetic agents used in Ireland is sevoflurane • Sevoflurane is the least damaging gas to the environment • Minor modifications in the use of these gases can have an environmental impact [ABSTRACT FROM AUTHOR]

• The nosZ gene of N 2 O reductase determined by paddy soil tillage state. • The clade Ⅱ and Ⅰ nosZ gene was dominated in the tillage and fallow period, respectively. • Heavy-metal pollution inhibited the N 2 O emission while not affecting the genes' switch. • The genus Bradyhizobium most significantly regulated the N 2 O flux. Paddy soils are an important source of atmospheric nitrous oxide (N 2 O). However, numerous studies have focused on N 2 O production during the soil tillage period, neglecting the N 2 O production during the dry fallow period. In this study, we conducted an incubation experiment using the acetylene inhibition technique to investigate N 2 O emission and reduction rates of paddy soil profiles (0-1 m) from Guangdong Province and Jinlin Province in China, with different heavy-metal pollution levels. The abundance and community structures of denitrifying bacteria were determined via quantitative -PCR and Illumina MiSeq sequencing of nosZ, nirK , and nirS genes. Our results showed that the potential N 2 O emission rate, N 2 O production rate, and denitrification rate have decreased with increasing soil vertical depth and heavy-metal pollution. More importantly, we found that the functional gene type of N 2 O reductase switched with the tillage state of paddy soils, which clade Ⅱ nosZ genes were the dominant gene during the tillage period, while clade Ⅰ nosZ genes were the dominant gene during the dry fallow period. The heavy-metal pollution has less effect on the niche differentiation of the nosZ gene. The N 2 O emission rate was significantly regulated by the genus Bradyhizobium , which contains both N 2 O reductase and nitrite reductase genes. Our findings suggests that the nosZ gene of N 2 O reductase can significantly impact the N 2 O emission from paddy soils. [Display omitted] [ABSTRACT FROM AUTHOR]

To assess the aetiology, management and outcomes of cold burn injuries presenting to a regional burn unit in the United Kingdom. Retrospective cohort study of consecutive patients over a 5-year period (2018–2022). Sixty-two patients (M:F 34:38; median age 23.5 years) were identified. The most common aetiology was aerosol (n = 28, 45.2%). Seven (11.5%) injuries were sustained during a social media or peer 'challenge' and 19 (31.2%) were self-harm, of whom 5 (26.3%) were inpatients on a mental health ward at the time of injury. All 'challenge' and self-harm injuries were caused by aerosol. Patients with 'challenge' injury were younger than those with self-harm (p =.007) and non-intentional injuries (p <.001). A greater proportion of self-harm injuries were in female patients compared with non-intentional injuries (p <.001). Median total body surface area (TBSA) was 0.35% (IQR: 0.3). Most burns were superficial partial thickness (n = 35, 56.5%), followed by deep dermal (n = 18, 29.0%), full-thickness (n = 8, 12.9%), and superficial (n = 1, 1.6%). The upper limb was most frequently affected (n = 35, 56.5%). Aetiology and a non-intentional, 'challenge' or self-harm injury did not affect TBSA (p = 0.776 and p = 0.364) or depth (p = 0.353 and p = 0.381). Five (8.1%) patients underwent autografting. The median time to healing was 17 days (range: 7–45, IQR: 22.75). Follow-up ranged from 1 to 173 weeks. The incidence of cold burns has increased when compared with previous literature. A disproportionate number of cold burns are self-inflicted using aerosols, either as self-harm or because of social media or peer 'challenges'. Other emerging aetiologies include non-intentional skin contact with nitrous oxide containers during its recreational use. [ABSTRACT FROM AUTHOR]

In this work, the explosion of hydrogen/nitrous oxide/carbon dioxide mixtures with various equivalence ratios (0.6–1.0), initial pressures (40–100 kPa), and carbon dioxide fractions (20%–40 %) at ambient temperature (298 K) was conducted inside a normative 15.625-L cubic container. The maximum explosion pressure and pressure rise speed were obtained and analyzed. The results show that carbon dioxide plays a crucial role in weakening H 2 /N 2 O explosion intensity, flame instabilities, as well as the tendency of deflagration to detonation. In addition, the addition of carbon dioxide has affected the two competitive effects between adiabatic temperature and molecular number. The variations of maximum explosion pressure and pressure rise speed with equivalence ratios depend on the carbon dioxide fraction. Only a linear dependence was found between maximum pressure rise speed and original pressure. These results would be useful in developing explosion-proof devices in the event of potential fire and explosion hazards. • Highlights (for review). • Carbon dioxide plays a significant role in weakening H 2 /N 2 O explosion intensity. • The variations of (d p /d t) max - φ depend on the carbon dioxide fraction. • The competitive effects between adiabatic temperature and molecular number are affected by CO 2. • The addition of CO2 effectively suppresses the tendency of deflagration to detonation. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N 2 O) is an environmentally damaging gas and alternative methods for its abatement are needed. In this work, we developed an electrochemical route using the mixed ionic electronic conductor Sr 2 Fe 1·5 Mo 0·5 O 6- δ (SFMO) as electrocatalyst for N 2 O reduction in the temperature range of 600–800 °C, at ambient pressure, for application in Solid Oxide Fuel Cells (SOFCs). The electrode mechanism, studied by electrochemical impedance spectroscopy (EIS), is discussed to involve a competition between both O 2 and N 2 O species, particularly at lower temperatures, where N 2 O thermal decomposition is lower. In terms of electrocatalytic properties, galvanostatic transients were used to assess N 2 O electroreduction on the SFMO electrode. The results showed that, after cathodic polarization, the N 2 O conversion increases. In particular, a highest Faradaic efficiency (| Λ|) of 3.94 was obtained at 600 °C. The reversibility of the mechanism was also assessed, and the results showed that the reaction rate returns to its open circuit value upon current interruption. This work indicates, therefore, that the electrochemical promotion of N 2 O reduction can be an attractive tool to be implemented for the reduction of this environmentally damaging gas in SOFC systems. • The viability of SFMO as electrocatalysts for N 2 O reduction is demonstrated. • The N 2 O electroreduction mechanism on the SFMO cathode is outlined. • Competition between O 2 electroreduction and N 2 O decomposition is suggested. [ABSTRACT FROM AUTHOR]

Respiratory gas analysis is a minimum standard of monitoring during general anaesthesia. It is also essential to know the environmental concentration of anaesthetic vapours in order to comply with regulations set out by the Control of Substances Hazardous to Health. Methods of measuring gas concentrations can be organized according to measurement in the gaseous state or in solution. Devices which are capable of measuring gas concentrations in the gaseous state include the paramagnetic analyser, infrared analyser, Raman effect analysers, mass spectrometry, refractrometry, piezoelectric absorption and ultraviolet absorption. Devices used to measure gas concentrations in solution include the Clark electrode, fuel cell, Severinghaus electrode and chromatography. This review will explain the basic principles behind each of these devices as well as discussing their advantages, disadvantages and potential sources of error. [ABSTRACT FROM AUTHOR]

A detailed experimental and numerical investigation of the combustion characteristics of carbon-free NH 3 /H 2 blends in N 2 O was performed in the present work. The experiments with various hydrogen fractions (α = 0–1.0) and equivalence ratios (φ = 0.6–1.4) were performed at ambient pressure (1 atm) and temperature (283 K) in a standard 3.375-L cubic combustion vessel. The explosion behaviors (maximum explosion pressure P max and maximum pressure rise rate (d p / d t) max) were obtained from the pressure-time curves. Further, the combustion characteristics (e.g. laminar burning velocity (S L), thermal expansion ratio (σ), flame thickness (δ), effective Lewis number (L e e f f ) and Markstein length (L b)) were calculated numerically by means of chemical kinetic analysis using Zhang's mechanism (Zhang et al. , Combust. Flame, 2017, 182: 122–141). Besides, sensitivity analyses of the explosion pressure and laminar burning velocity were performed to identify the contribution of dominant elementary reactions. The results show that, for combustion supported by N 2 O, the flame instability and the potential of deflagration to detonation transition (DDT) should be considered for the evaluation of P max and (d p / d t) max. Moreover, the hydrodynamic instability of premixed H 2 /NH 3 /N 2 O flame reaches its peak near the stoichiometric ratio and increases monotonously with the hydrogen fraction. The diffusion-thermal instability is more significant in the leaner mixture, and it is not invariably enhanced with the increase of hydrogen fraction but is relevant to the composition of the mixture. In addition, the sensitivity analysis of explosion pressure demonstrates that R80 (N 2 O + H 2 N 2 +H 2 O) and R70 (N 2 O+(M) = N 2 +O (+M)) are the most dominant reactions contributing to the pressure rise. The sensitivity analysis of laminar burning velocity shows that R70 (N 2 O+(M) = N 2 +O (+M)), R71 (N 2 O + H N 2 +OH) and R80 (N 2 O + H 2 N 2 +H 2 O) are the most dominant reactions enhancing laminar burning velocity. • The combustion characteristics of NH 3 /H 2 blends in N 2 O were firstly investigated. • The flame instability and DDT were considered for the combustion supported by N 2 O. • The parameters of hydrodynamic and diffusion-thermal instability were analyzed. • The sensitivity analysis based on different mechanisms was performed. [ABSTRACT FROM AUTHOR]

• Significant effects of key drivers on gaseous emissions from cattle housing were identified. • NH 3 emissions differ between housing types but not between floor types. • CH 4 emissions differ by barn temperature and relative humidity only. • N 2 O and NH 3 emissions are lower in temperate wet zones than in temperate dry zone. • Global data analysis shows the need to differentiate emission factors by agro-ecosystems. This study provides a meta-analysis on the relationships between cattle barn CH 4 , NH 3 and N 2 O emission rates and their key drivers (i.e., housing type, floor type, environmental conditions). Understanding these relationships is essential to reduce uncertainties in emission inventories and suggest targeted mitigation measures. The total number of daily emission rates included in the analysis was 139 for CH 4 , 293 for NH 3 and 100 for N 2 O emissions. Emission rates in the database showed a large variation with 45–803.5 g/LU d−1 for CH 4 , 0.036–146.7 gN LU−1 d−1 for NH 3 , and 0.002–18 gN LU−1 d−1 for N 2 O emissions. Despite the high emission variability, significant effects were identified·NH 3 showed positive correlation with air temperature; NH 3 emissions differed between housing types but not between floor types·NH 3 emissions from tied stalls were lower than the ones from cubicle housing regardless of the floor type. Additionally, NH 3 emissions from loose housings were lower than the ones from cubicle housing·NH 3 and N 2 O emission rates from temperate wet zones were lower than the ones from temperate dry zones. CH 4 emission rates were affected by environmental factors only and not by housing and floor type, showing negative correlation with air temperature and humidity. The factors investigated can be suggested as ancillary variables and descriptors when cattle barn emissions are measured, in order to make best use of emission data. Country-specific data of these key drivers can be included into national inventories to adapt them to different agroecosystems and support targeted policies. [ABSTRACT FROM AUTHOR]

There is limited data regarding dose and duration of nitrous oxide use by women in peripartum care. Experiences of using nitrous in Australian settings have not previously been explored More than 1:2 women use nitrous oxide analgesia during labour and birth, despite this, there are limited published data on nitrous oxide use for labour or procedural analgesia in Australia. To explore the use of nitrous oxide during labour and birth or procedural care. A two-phased sequential design was used; clinical audit (n = 183) and cross-sectional survey (n = 137) approaches supported data collection. Quantitative data were analysed using descriptive and inferential statistics, qualitative data underwent content analysis. Nitrous oxide was used by primiparous and multiparous women evenly. Duration of labour-use ranged from < 15 min (10.9%) to > 5 h (10.8%), with equal representation between > 50% concentration (43%) and < 50% (43%). At audit, 75% found nitrous useful; postpartum maternal satisfaction scores remained high, mean indicators were 75%. More multiparous women found nitrous oxide useful than primiparous (95%vs80%,p = 0.009). There was no association between perceived usefulness and whether women were in spontaneous, augmented or induced labour; regardless of concentrations reached. Three key themes described women's perspectives of physical and psycho-emotional effects and challenges. Nitrous oxide plays an important role in the provision of analgesia during procedural or labour and birth care. Service provision, parent and professional education, and future service design will benefit from these novel findings confirming the utility and acceptability of nitrous oxide use in contemporary maternity care. [ABSTRACT FROM AUTHOR]

There is little documented evidence of midwives' perspectives regarding the use of nitrous oxide in the peripartum period. Nitrous oxide is an inhaled gas used widely in the peripartum period; usually offered and managed by midwives. Explore midwives' knowledge, perceptions, and practices of facilitating women's use of nitrous oxide in the peripartum period. An exploratory cross-sectional survey design was used. Quantitative data were analysed using descriptive and inferential statistics; open-ended responses underwent template analysis. Midwives (n = 121) working in three Australian settings reported regularly recommending the use of nitrous oxide and high levels of knowledge and confidence supporting its use. There was a significant association between midwifery experience, and perspectives on women's capacity to use nitrous effectively (p = 0.004); and desire for refresher education (p < 0.001). Midwives working in continuity models were more likely to support women using nitrous oxide in any situation (p = 0.039). Midwives demonstrated expertise in facilitating nitrous oxide use, citing utility to relieve anxiety and distract women from pain or discomfort. Nitrous oxide was identified as an important adjunct to the provision of supportive care requiring midwifery therapeutic presence. This study provides novel insight into midwives' support of nitrous oxide use in the peripartum setting revealing high levels of knowledge and confidence. Recognition of this unique expertise held by midwives is important to ensure transfer and development of professional knowledge and skills and emphasises the need for midwifery leadership in clinical service provision, planning and policy. [ABSTRACT FROM AUTHOR]

• Rice is one of the important cereals and staple food for more than half of the world. Climate change and diminishing resources are the major challenges in the sustainable rice production. • Aerobic rice system can be a transformational approach to replace conventional rice in face of climate change and scarcity of resources due to its high input-use efficiency. • Aerobic rice crop failure can be reduced if availability of suitable and stress resistant cultivars with early improved vigour, and short-duration characteristics is ensured for maintaining the reproductive capability under resource stressed environment. • Several constraints are associated with the shift from flooded to aerobic rice brings changes in crop water demand, organic matter (OM) turnover, N dynamics, weed flora, and greenhouse gases (GHGs) emissions. Along with N-losses, continuous monocropping, higher weed infestation, weedy rice emergence, nitrous oxide (N 2 O) emissions, nutrient disorders, higher prevalence of pathogens and diseases, increased panicle sterility, and an increase in soilborne pathogens lodging are other major constraints negatively impacting the widespread adaptation of aerobic rice. • This article reviews the climate change status, its associated impacts on the sustainability of traditional rice system, and the rationale for transforming from traditional to aerobic rice system. • Furthermore, it described the major constraints and challenges associated in the wider adaptation of the new approach for sustainable rice production under in face of projected climate change and scarcity of resources. • Lastly, this article highlights the potential management measures to reduce the associated risks in aerobic rice system. Climate change and diminishing resources are the major challenges in sustainable rice production. The aerobic rice system can be a transformational approach to replace conventional rice in the face of climate change and scarcity of resources due to its high input-use efficiency. However, it could not be adapted widely yet due to several challenges like higher weed infestation and low nitrogen (N) use efficiencies. This transformed system can only be adapted at a wider scale through investigation of associated constraints and risks and provision of potential adjustive measures. Aerobic rice crop failure can be reduced if the availability of suitable and stress-resistant cultivars with early improved vigour, and short-duration characteristics are ensured for maintaining the reproductive capability under resource stressed environment. This transformed rice system exhibits limited response to applied N because of increased losses due to higher volatilization and rapid coupled nitrification-denitrification processes under alternate wetting and drying systems. Shifting from the flooded to aerobic rice system bringing changes in crop water demand, organic matter (OM) turnover, N dynamics, weed flora, and greenhouse gases (GHGs) emissions. Along with N-losses, continuous monocropping, higher weed infestation, weedy rice emergence, nitrous oxide (N 2 O) emissions, nutrient disorders, higher prevalence of pathogens and diseases, increased panicle sterility, and an increase in soilborne pathogens lodging are other major constraints negatively impacting the widespread adaptation of aerobic rice. This article reviews the climate change status, its associated impacts on the sustainability of traditional rice systems, and the rationale for transforming from traditional to aerobic rice systems. Furthermore, it describes the major challenges associated with the aerobic rice system, thereby presenting management strategies ensuring its wider adaptation for sustainable rice production in the face of projected climate change and scarcity of resources. [ABSTRACT FROM AUTHOR]

• Cornstalk and sawdust reduced greenhouse effects by 29.87%–33.60% during storage. • Cornstalk and sawdust cover reduced N 2 O emissions via physical biotransformation. • Some bacteria in organic materials were transferred to covering materials. • The fibrous structures of coverages were eliminated and became more disorderly. Manure covered by organic materials during the storage has shown that it can effectively reduce emissions of greenhouse gases, but few studies have focused on the bacterial communities in manure or the coverage and mechanism responsible for reducing gas emissions. Therefore, this study investigated the impacts and mechanisms of cornstalk and sawdust coverings on greenhouse gas emissions during sheep manure storage. Sheep manure covered by organic material reduced nitrous oxide (N 2 O) emissions (42.27%–42.55%) relative to uncovered control through physical adsorption and biological transformation of Acinetobacter , Corynebacterium, Brachybacterium , Dietzia and Brevibacterium. Sheep manure covered by organic materials also increased methane (CH 4) emissions (16.31%–43.07%) by increasing anaerobic zones of coverage. Overall, coverings reduced carbon dioxide equivalent (CO 2 eq) by 29.87%–33.60%. Coverings had less effect on the bacterial diversity and community of sheep manure, and the number of bacteria shared by sheep manure and the covering material increased with storage progress, indicating that these bacteria were transferred to the covering materials with gas emissions and moisture volatilization. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) images showed that functional group intensities of the covering materials increased and the fibrous structures became more disordered during the storage period. In general, it was safe to use organic materials as coverages during sheep manure storage, which was conducive to reducing greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

The laminar burning velocity and cellular instabilities of premixed flame in H 2 -N 2 O mixtures were studied experimentally at various equivalence ratios (φ) and initial pressures (p 0). High-speed schlieren was used to record the morphology of the spherical flame. Based on the spherical flame method, the laminar burning velocity and Markstein length were derived. In addition, the Lewis number, flame thickness, thermal expansion and Zel'dovich number were evaluated numerically. The results show that both the laminar burning velocity and Markstein length increase with the equivalence ratio. The Lewis number (less than unity) increases with the equivalence ratio while the flame thickness exhibits an inverse evolution. Hence, the most unstable flames were found to be at φ = 0.4–0.6 due to the combined effects of the thermal-diffusion and hydrodynamic instabilities. At lower initial pressure, the flame front is smooth in spite of the diffusion-thermal instability. With the increase of initial pressure, both the diffusion-thermal instability and hydrodynamic instability dominate the cellular structure of the flame front. The flames undergo self-acceleration at φ = 0.4–0.6 and p 0 = 40 kPa, with the acceleration exponents close to 1.5 (the value of self-turbulization). Due to the local oscillation of velocity, the flame propagation speed decreases after the self-similar regime. [ABSTRACT FROM AUTHOR]

• Remarkable spatiotemporal pattern of N2O concentrations and fluxes were observed. • Factors controlling N2O emission vary across lake zones and seasons. • Seasonally frozen eutrophic shallow lakes in cold regions can be a source of N2O. • Northern part of the lake near the drained inlet is a "hotspots" for N2O emission. Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide (N 2 O), while regional and global estimates have remained imprecise. This due to a lack of data and insufficient understanding of the multiple contributing factors. This study characterized the spatiotemporal variability in N 2 O concentrations and N 2 O diffusive fluxes and the contributing factors in Lake Wuliangsuhai, a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate. Dissolved N 2 O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L, displaying significant spatiotemporal variations. The lowest and highest concentrations were measured in summer and winter, respectively. The spatial distribution of N 2 O flux was consistent with that of N 2 O concentrations. Additionally, the hotspots of N 2 O emissions were detected within close to the main inflow of lake. The wide spatial and temporal variation in N 2 O emissions indicate the complexity and its relative importance of factors influencing emissions. N 2 O emissions in different lake zones and seasons were regulated by diverse factors. Factors influencing the spatial and temporal distribution of N 2 O concentrations and fluxes were identified as WT, WD, DO, Chl-a, SD and COD. Interestingly, the same factor demonstrated opposing effects on N 2 O emission in various seasons or zones. This research improves our understanding of N 2 O emissions in shallow eutrophic lakes in cold and arid areas. [Display omitted] [ABSTRACT FROM AUTHOR]

Rising demand for protein-rich foods can impact N 2 O emissions from croplands. Recent research has pointed to the role of modified plant vasculature in grain protein increase. Here we highlight how discovering the mechanistic role of plant vasculature in protein improvement and nitrogen-use efficiency could reduce global N 2 O emissions. [ABSTRACT FROM AUTHOR]

Labor pain is among the most severe types of physical pain that women may experience during their lifetime. Thus, pain relief is an essential part of medical care during childbirth. Epidural analgesia is considered to be the most efficient method of pain relief during labor. Nevertheless, patient preferences, contraindications, limited availability, and technical failure may require the use of alternative pain reliving methods during labor including systemic pharmacologic agents, and nonpharmacologic methods. Nonpharmacologic methods for pain alleviation during vaginal birth have become popular over the years, either as a complement to pharmacologic agents or at times as the principal therapy. Methods such as relaxation techniques (ie, yoga, hypnosis, and music), manual techniques (ie, massage, reflexology, and shiatsu), acupuncture, birthing ball, and transcutaneous electrical nerve stimulation are considered safe, although the evidence supporting their effectiveness for pain relief is not as robust as it is for pharmacologic agents. Systemic pharmacologic agents are mostly administered by inhalation (nitrous oxide) or through the parenteral route. These agents include opioids such as meperidine, nalbuphine, tramadol, butorphanol, morphine, and remifentanil, and non-opioid agents such as parenteral acetaminophen and nonsteroidal anti-inflammatory drugs. Systemic pharmacologic agents suggest a diverse armamentarium of medication for pain management during labor. Their efficacy in treating pain associated with labor varies, and some continue to be used even though they have not been proven effective for pain relief. In addition, the maternal and perinatal side effects differ markedly among these agents. There is a relative abundance of data regarding the effectiveness of analgesic drugs compared with epidural, but the data regarding comparisons among the different types of alternative analgesic agents are scarce, and there is no consistency regarding the drug of choice for women who do not receive epidural pain management. This review aims to present the available data regarding the effectiveness of the different methods of relieving pain during labor other than epidural. The data presented are mainly based on recent level I evidence regarding pharmacologic and nonpharmacologic methods for pain relief during labor. [ABSTRACT FROM AUTHOR]

Depuis quelques années nous assistons à une ascension de l'usage détourné du protoxyde d'azote comme produit stupéfiant. Certains risques liés à son utilisation sont désormais bien connus, en particulier neurologiques et psychiatriques. Dans cette étude, nous souhaitons faire état du risque de brûlures, conséquence d'un phénomène de refroidissement des bonbonnes métalliques lors de la détente brusque du gaz sous pression. Entre novembre 2021 et août 2022, nous avons pris en charge quatre patients pour des brûlures profondes causées par le mésusage du protoxyde d'azote. Il s'agissait de trois femmes et un homme avec une moyenne d'âge de 28 ans. Deux d'entre eux étaient suivis en addictologie. Nous observions un retard moyen à la prise en charge de 7 jours. Dans toutes les situations, il s'agissait de brûlures de troisième degré, de forme arrondie, au niveau des cuisses, et d'indication chirurgicale. Pour trois des patients (l'un ayant été perdu de vue), une excision-greffe a été effectuée dans un délai moyen de 32 jours. Au même titre que de nombreux produits stupéfiants, l'usage non médical du protoxyde d'azote représente un réel problème de santé publique, se surajoutant aux effets indésirables propre de la substance. Des mesures de prévention et de sécurité sanitaire sont indispensables. In recent years, we have seen an increase in the frequency of the misuse of nitrous oxide as a narcotic. The risks associated with its use are now well-known, such as neurological and psychiatric risks. In this study, we report our experience with specific thigh burns when using nitrous oxide canisters for narcotic purposes. Between November 2021 and August 2022 we treated 4 patients burned during a nitrous oxide use accident. We report the cases of three women and one man with an average age of 28. Two of them were treated in addictology. We observed an average delay before consultation of a healthcare professional of 7 days. The burns were all rounded and deep, localized at the level of the thighs. For three of the patients (one having been lost to sight), a split thickness skin graft was performed within an average of 32 days. The non-medical use of nitrous oxide represents a real public health problem in addition to the adverse effects of the substance itself. Prevention and health security measures seem to be becoming essential. [ABSTRACT FROM AUTHOR]

In order to achieve carbon neutrality, the use of ammonia as a fuel for power generation is highly anticipated. The utilization of a binary fuel consisting of ammonia and hydrogen can address the weak flame characteristics of ammonia. In this study, the product gas characteristics of ammonia/hydrogen/air premixed laminar flames stabilized in a stagnation flow were experimentally and numerically investigated for various equivalence ratios for the first time. A trade-off relationship between NO and unburnt ammonia was observed at slightly rich conditions. At lean conditions, NO reached a maximum value of 8,700 ppm, which was larger than that of pure ammonia/air flames. The mole fraction of nitrous oxide (N 2 O) which has large global warming potential rapidly increased around the equivalence ratio of 0.6, which was attributed to the effect of a decrease in flame temperature downstream of the reaction zone owing to heat loss to the stagnation wall. To understand this effect further, numerical simulations of ammonia/hydrogen/air flames were conducted using the stagnation flame model for various equivalence ratios and stagnation wall temperatures. The results show that the important reactions for N 2 O production and reductions are NH +NO = N 2 O + H, N 2 O + H = N 2 + OH, and N 2 O (+M) = N 2 + O (+M). A decrease in flame temperature in the post flame region inhibited N 2 O reduction through N 2 O (+M) = N 2 + O (+M) because this reaction has a large temperature dependence, and thus N 2 O was detected as a product gas. N 2 O is reduced through N 2 O (+M) = N 2 + O (+M) in the post flame region if the stagnation wall temperature is sufficiently high. On the other hand, it was clarified that an increase in equivalence ratio enhances H radical production and promotes N 2 O reduction by H radical through the reaction of N 2 O + H = N 2 + OH. [ABSTRACT FROM AUTHOR]

• We provided the first proof of concept for N 2 O recovery driven by sulfide in denitrification process. • The percentage of N 2 O in gaseous products was up to 82.9%. • Sulfide served as the inhibitor and electron donor. • Changes in morphology make cytochrome c lose capability on electron transport. We propose a novel sulfide-driven process to recover N 2 O during the traditional denitrification process. The optimum initial sulfide concentration was 120 mg/L, and the N 2 O percentage in the gaseous products (N 2 O+N 2) was up to 82.9%. Moreover, sulfide involved in denitrification processes could substitute for organic carbon as an electron donor, e.g., 1 g sulfide was equivalent to 0.5-2 g COD when sulfide was oxidized to sulfur and sulfate. The accumulation of N 2 O was mainly due to the inhibiting effect of sulfide on nitrous oxide reductase (N 2 OR), which was induced by the supply insufficiency of electrons from cytochrome c (cyt c) to N 2 OR. When the initial sulfide concentration was 120 mg/L, the N 2 OR activity was only 36.8% of its original level. According to the results of cyclic voltammetry, circular dichroism spectra and fluorescence spectra, significant changes in the conformations and protein structures of cyt c were caused by sulfide, and cyt c completely lost its electron transport capacity. This study provides a new concept for N 2 O recovery driven by sulfide in the denitrification process. In addition, the findings regarding the mechanism of the inhibition of N 2 OR activity have important implications both for reducing emissions of N 2 O and recovering N 2 O in the sulfide-driven denitrification process. [Display omitted]. [ABSTRACT FROM AUTHOR]

• High TN removal efficiency of 85% was obtained with a soluble COD/N ratio of 0.5. • Partial denitrification-anammox played a key role in nitrogen removal. • Particulate slowly biodegradable COD (pCOD) inhibited nitrogen removal performance. • Denitrification was more sensitive to pCOD than anammox. • High content of pCOD resulted in N 2 O accumulation up to 0.25mg N/L. In this study, the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated. The results of the long-term experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity, to reach as high as 84.9%±2.8% TN removal efficiency. Partial denitrification-anammox (PDN/anammox) and denitrification were proposed as the major pathways for nitrogen removal, accounting for 91.3% and 8.7% of the TN removal, respectively. Anammox bacteria could remain active with high abundance of anammox genes to maintain its dominance. Candidatus Kuenenia and Thauera were the predominant genera in the presence of organic matter. Compared with sCOD, batch experiments showed that the introduction of pCOD had a negative effect on nitrogen removal. The contribution of denitrification to nitrogen removal decreased from approximately 14% to 3% with increasing percentage of pCOD. In addition, the analysis result of the process data using an optimized ASM1 model indicated that high percentage of pCOD resulted in serious N 2 O emission (the peak value up to 0.25 mg N/L), which was likely due to limited mass diffusion and insufficient available carbon sources for denitrification. However, a high sCOD/N ratio was beneficial for alleviating N 2 O accumulation. [Display omitted] [ABSTRACT FROM AUTHOR]

We report dissolved CO 2 , CH 4 and N 2 O concentrations in two large East African lakes, Edward (surface area 2,325 km2, average depth of 37 m) and George (surface area 273 km2, average depth of 2 m). Lake George showed modest seasonal and spatial variations, and lower partial pressure of CO 2 (pCO 2) (26 ± 16 ppm, mean ± standard deviation), CH 4 (234 ± 208 nmol/L) and N 2 O saturation levels (%N 2 O) (80 ± 9 %) than Lake Edward (404 ± 145 ppm, 357 ± 483 nmol/L, 139 ± 222 %). Surface waters in both lakes were over-saturated in CH 4 , and Lake George was under-saturated in CO 2 while Lake Edward was slightly over-saturated in CO 2. This difference was related to higher phytoplankton biomass in Lake George than Lake Edward, with average chlorophyll-a concentrations of 177 ± 125 and 18 ± 25 µg/L, respectively. Permanent high cyanobacterial biomass in Lake George led to uniform dissolved CO 2 , CH 4 and N 2 O concentrations. In surface waters of Lake Edward, spatial variations of pCO 2 , CH 4 and N 2 O were related to bottom depth, and locally (in particular in Katwe Bay) also related to the inputs of water from Lake George via the Kazinga Channel, a 40-km natural channel connecting the lakes. Short-term mixing events related to storms increased CO 2 , CH 4 and N 2 O content in surface waters, in particular for CH 4 and N 2 O. This indicates that mixing events in response to storms can create 'hot moments' for CH 4 and N 2 O emissions to the atmosphere in tropical lakes, given the weaker vertical density gradients compared to higher latitude systems. [ABSTRACT FROM AUTHOR]

Composting process is accompanied by the emission of greenhouse gases such as nitrous oxide (N 2 O). Biochar addition effectively reduced the release of N 2 O. However, the specific impact mechanism of biochar is unclear. Therefore, the aim of this study was to reveal the response of N 2 O-related microorganisms to biochar addition during chicken manure composting. Results suggested that the addition of biochar reduced the species of N 2 O-related microorganisms from 22 to 19, and changed the functional roles. Network analysis further revealed that the addition of biochar weakened the transformation relationship between nitrification and denitrification, which effectively inhibited the denitrification rate. Ultimately, Structural equation models verified that the addition of biochar made core microorganism Ornithinibacillus prevail, which weakened the denitrification during composting. This study identified the core microorganisms that regulated the production of N 2 O during chicken manure composting, and provided a theoretical basis for the targeted regulation of N 2 O emission. [Display omitted] [ABSTRACT FROM AUTHOR]

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Nitrous oxide (N 2 O) is a noncompetitive inhibitor of NMDA receptors that appears to have ketamine-like rapid antidepressant effects in patients with treatment-resistant major depression. In preclinical studies, ketamine enhances glutamate-mediated synaptic transmission in the hippocampus and prefrontal cortex. In this study, we examined the effects of N 2 O on glutamate transmission in the hippocampus and compared its effects to those of ketamine. Glutamate-mediated synaptic transmission was studied in the CA1 region of hippocampal slices from adult albino rats using standard extracellular recording methods. Effects of N 2 O and ketamine at subanesthetic concentrations were evaluated by acute administration. Akin to 1 μM ketamine, 30% N 2 O administered for 15–20 minutes resulted in persistent enhancement of synaptic responses mediated by both AMPA receptors and NMDA receptors. Synaptic enhancement by both N 2 O and ketamine was blocked by co-administration of a competitive NMDA receptor antagonist at saturating concentration, but only ketamine was blocked by an AMPA receptor antagonist. Synaptic enhancement by both agents involved TrkB (tropomyosin receptor kinase B), mTOR (mechanistic target of rapamycin), and NOS (nitric oxide synthase) with some differences between N 2 O and ketamine. N 2 O potentiation occluded enhancement by ketamine, and in vivo N 2 O exposure occluded further potentiation by both N 2 O and ketamine. These results indicate that N 2 O has ketamine-like effects on hippocampal synaptic function at a subanesthetic, but therapeutically relevant concentration. These 2 rapid antidepressants have similar, but not identical mechanisms that result in persisting synaptic enhancement, possibly contributing to psychotropic actions. [ABSTRACT FROM AUTHOR]

Co 3 O 4 coated on open-cell metallic foams, which can merge the catalytic activity of Co 3 O 4 and advantages derived from the geometry of the support, are promising for environmental applications such as the decomposition of N 2 O (deN 2 O). This study demonstrates how it is possible to easily and reproducibly prepare a well-adhered layer of Co 3 O 4 with a similar specific surface area as the materials prepared with the precipitation method (∼ 23 m2 g−1 coating) and controlled thickness on FeCrAlloy open-cell foams of different porosity and dimension by the electrosynthesis of Co(OH) 2 followed by thermal treatment (600 °C). The obtained structured catalysts show stable performance after three cycles of catalytic decomposition of N 2 O between 250 and 550 °C, with a similar T 50 of approximately 460 °C, which is comparable to the combustion or precipitated catalysts but provides a lower pressure drop. Under the operating conditions with a sequential test, the presence of NO and/or O 2 in the feed gas inhibits partially the catalytic activity of the structured catalysts while the presence of H 2 O shows a slight enhancement in the N 2 O conversion at a temperature above 450 °C. [Display omitted] • Co(OH) 2 layer is easily coated on FeCrAlloy open-cell foam by electrodeposition. • Calcination at 600 °C results in a stable coating of Co 3 O 4 with a high specific surface area. • Catalyst loading can be tailored by synthesis time and electrolytic concentration. • T 50 for deN 2 O is in a range of 477–543 °C with the presence of O 2 , NO, and H 2 O. • Promising use in other energy and environmental applications. [ABSTRACT FROM AUTHOR]

Acidic nitrogenous wastewater often requires alkali pretreatment before biological treatment, which results in increased system complexity and operating costs. The demonstration of denitrification under acidic conditions would provide a theoretical basis for the direct treatment of such wastewater. In this study, the denitrification performance, microbial community, and nitrous oxide (N 2 O) emissions under acidic conditions were investigated using a sequencing batch reactor. When the influent pH decreased from 5.5 to 4.5, the sequencing batch reactor removed 99.8 ± 0.2% of the nitrate and 92.5 ± 1.6% (n = 171) of the chemical oxygen demand, and the production efficiency of N 2 O increased significantly to 11.45%. This was 2.6-fold higher than that observed at pH 5.5. The long-term denitrification treatment of acidic wastewater (pH 4.5) led to the formation of granular sludge, and Thauera , Allorhizobium-Neorhizobium-Parararhizobium-Rhizobium, and Diaphorobacter became the dominant microbes with a collective abundance of 81.3%. More importantly, only 0.25% of the nitrate was denitrified as N 2 O, and the batch test revealed that the emissions of N 2 O decreased with the increase in sludge size. These results indicate that denitrifying granular sludge formed under acidic conditions and denitrifying bacteria capable of N 2 O reduction proliferated, which both resulted in a significant reduction in the release of N 2 O. [Display omitted] • After long-term operation at acidic pH, only 0.25% of nitrate was reduced to N 2 O. • Granules formed in denitrification SBR for acidic wastewater treatment. • Thauera becomes the dominant bacterium in acidic denitrification systems. • N 2 O release significantly decreases with increasing sludge particle size. [ABSTRACT FROM AUTHOR]

Various transition metals were employed to enhance the catalytic performance and N 2 selectivity of Mn-based catalysts. The modification of Fe and Cu promoted the low-temperature activity, while the Al-modified catalyst displayed the highest N 2 selectivity close to 100 %. The characterization results proved that the content of O β and Mn4+ were increased after adding transition metals. N 2 selectivity experiments revealed that the reduction of NO to N 2 O and the oxidation of NH 3 to N 2 O did not occur. The product of NH 3 oxidation was only N 2. Combined with the results of the in-situ DRIFTS experiments, it was proposed that N 2 O was generated from the decomposition of NHNO and NH 4 NO 3 in the SCR reaction. The poor N 2 selectivity of the unmodified catalyst was related to the existence of inactive N 2 O 2 2- species on the surface, while the high content of active NH 2 - species on the Mn 0.1 Ho 0.005 Ce 0.015 Al 0.01 /TiO 2 catalyst enhanced its catalytic activity and N 2 selectivity. In addition, the results also revealed that only the E-R mechanism existed on the unmodified catalyst, while both the E-R and L-H mechanism were activated after the transition metal modification. The SCR reaction of NH 3 and NO proved to be the source of N 2 O. The activation of the L-H mechanism might play a key role in the improvement of activity and selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Laboratory setup for the study of the Ostwald process under industrial conditions. • Highly reproducible process parameter screening within hours. • All parameters have been statistically fully decorrelated. • Interaction of the process parameters have been described for a first time. • Optimized conditions for lower nitrous oxide emission have been determined. Nitrous oxide (N 2 O) represents one of the key chemicals regarding climate change due to the high global warming potential and significant annual emissions. The largest industrial contribution results from the catalytic oxidation of ammonia to nitric acid, known as the Ostwald process. Successful efforts to reduce the emissions have been made for decades, but mainly focus on secondary and tertiary reduction. However, due to the severe process parameters, only a few publications were able to study the primary reduction – minimizing the formation in the first place – under industrial conditions. Here we present a laboratory setup with an extended range of parameters reflecting and exceeding industrial conditions, while allowing for reproducibility of over 99.9 %. The reactor was successfully employed for process parameter analysis and optimization via a data-driven approach through statistical analysis within design of experiments. Increasing preheating temperature by 200 °C and ammonia volume fraction by 4 % L/L decreased nitrous oxide selectivity by a factor of 2.7 and 3.1 respectively, while an increase in pressure from 2.5 to 4.3 bar promoted laughing gas formation by 38 %. Additionally, the volume flow has been found to be statically insignificant. Furthermore, for the first time the non-linear and interaction effects of all process parameters have been deduced. The interaction between pressure and ammonia concentration, as well as pressure and preheating temperature decreases nitrous oxide formation and can even reverse the primary effect of pressure. These findings pave a path for an alternative way of optimization of the Ostwald process alongside the more common kinetic-based optimizations. [ABSTRACT FROM AUTHOR]

• Greenhouse gas budgets of pasture grazed year-round. • The old pasture was a carbon source to the atmosphere. • The renewed pasture was a carbon sink. • Fertilization and rainfall conditions can change the pasture carbon sink to source. • The wet soil was temporarily an N 2 O sink. The recovery of degraded pastures and the increase in their capacity for storing carbon is a key strategy in Brazil's commitment to meeting its Nationally Determined Contribution (NDC) to the international effort to halt global warming. Here we report the fluxes of CO 2 , N 2 O and CH 4 gasses and their balances, obtained by the eddy covariance method, from a representative pasture area in southeast Brazil. The measurements covered more than five years, starting with the old degraded pasture, covering the renewal process and then the re-establishment of pasture. The latter only received nitrogen fertilization once after the renewal – the common practice. The net ecosystem carbon balance (NECB), which considered the sum of the net ecosystem exchange (NEE pasture) of CO 2 and methane (FCH4 pasture) without the cattle respiration and enteric fermentation, as well the export/import of carbon by grazing and as feces (stocking rates of 1.8 to 3.3 AU ha−1), was positive in the old pasture (236 ± 104 g CO 2 m −2 year−1) representing a source to the atmosphere, but a sink (negative) during the first year of the renewal (-1603 ± 122 g CO 2 m −2 year−1) when it was fertilized and the recorded rainfall was normal. In the following two years it was neutral (77 ± 93 and 5 ± 100 g CO 2 m −2 year−1), partially a consequence of the lower rainfall received. In the fourth year it was a sink again (-736 ± 131 g CO 2 m −2 year−1). On average the cumulative fluxes of CH 4 (42 ± 19 g CO 2 eq. m −2 year−1) without the animals' enteric fermentation and N 2 O (20 ± 10 g CO 2 eq. m −2 year−1) were small and positive, being offset by the net carbon gain. The NECB for this site covering the period of measurements was an overall source of 671 ± 254 g CO 2 m −2. [ABSTRACT FROM AUTHOR]

The construction of cascade reservoirs can interfere with the natural hydrologic cycles of basins, causing negative environmental effects such as altering the emission patterns of the Nitrous oxide (N 2 O), a potent greenhouse gas. To elucidate the impact of cascade reservoirs construction on river N 2 O emissions, we utilized the thin boundary model and the incubation experiments to estimate the N 2 O fluxes at the air-water interface and at the water-sediment interface of cascade reservoirs on the Yunnan-Guizhou Plateau, respectively. Additionally, we explored the influence of various factors, with particular emphasis on damming, on N 2 O emissions and production. Moreover, we identified the main pathways of N 2 O production and proposed management strategies to mitigate N 2 O emissions from cascade reservoirs. The findings revealed that N 2 O fluxes at the air-water interface and the water-sediment interface were 4.73 ± 1.32 μmol m−2 · d−1 and 15.56 ± 1.98 μmol m−2 · d−1, respectively. Influenced by temperature, dissolved oxygen (DO), resource substances (active nitrogen substrates and dissolved organic carbon (DOC)) and reservoir properties (scale, hydraulic retention time (HRT), reservoir age, etc.), the N 2 O concentration and flux exhibited notable spatial heterogeneity, gradually increasing downstream. Temperature has a significant direct impact on N 2 O flux, as well as indirect effects through DO and resource chemicals. Furthermore, the correlation between dissolved oxygen utilization rate (AOU) and net N 2 O flux (ΔN 2 O) indicated that N 2 O emissions at the water-air interface were primarily attributable to nitrification, whereas those at the water-sediment interface were predominantly driven by denitrification. These findings not only enhance our comprehension of N 2 O emissions at various interfaces of cascade reservoirs but also offer theoretical backing for the formulation of management strategies aimed at efficiently mitigating N 2 O emissions from continuously dammed rivers. [Display omitted] • Cascade reservoirs are sources of N 2 O emissions and display cumulative impacts. • Sediments or bottom water bodies, not surface water, significantly contribute to N 2 O emissions. • Temperature primarily influences N 2 O emissions, indirectly affecting DO, DOC, and DIN. • Nitrification and denitrification separately dominate N 2 O-production in surface and bottom waters. [ABSTRACT FROM AUTHOR]

• Natural gas vehicles demonstrated lower NOx emissions than diesel vehicles. • Strong dependence of NOx between drive cycles, with higher NOx under lower loads. • HVO showed NOx reductions for non-SCR vehicles, but not for SCR vehicles. • Natural gas vehicles showed higher ammonia emissions. • N 2 O emissions showed no strong trends, with many vehicles near detection limits. The current study characterized nitrogen oxide (NOx), nitrous oxide (N 2 O), and ammonia (NH 3) emissions from 14 heavy-duty vehicles from different vocations (school bus, transit bus, refuse hauler, delivery vehicle, and goods movement vehicle) over different drive cycles using a chassis dynamometer. Test vehicles with engines ranging in model year from 2009 to 2018 and including diesel and compressed natural gas (CNG) vehicles. The diesel vehicles included both vehicles without selective catalytic reduction (no-SCR) and with SCR certified to the 0.2 g per brake horsepower-hour (g/bhp-hr) [0.27 g/kilowatt-hour (kW-hr)] NOx emissions standard that were operated with diesel fuel, with a subset tested on hydrotreated vegetable oil (HVO). The CNG vehicles were all three-way catalyst (TWC) equipped and certified to either the 0.2 or 0.02 g/bhp-hr NOx standard [0.27 or 0.027 g/kW-hr]. This study is part of a larger project that included over 200 in-use heavy-duty vehicles, which is one of the most extensive studies of emissions from modern heavy-duty vehicles to date. NOx, NH 3 , and N 2 O emissions varied depending on the vocation and the technology. Average NOx emissions for the Urban Dynamometer Driving Schedule (UDDS) cycle over all vehicles ranged from 0.003 to 6.16 g/bhp-hr [0.004 to 8.25 g/kW-hr] and from 0.02 to 17.2 g/mile [0.012 to 10.7 g/km], with the diesel vehicles showing the highest emissions, the 0.2 g/bhp-hr certified CNG vehicles showing lower emissions, and the 0.02 g/bhp-hr certified CNG vehicles showing very low emissions. NOx emissions over other different cycles were generally in the same range as those for the hot start UDDS, with the highway cycles generally showing the lowest emissions. CNG vehicles had relatively high NH 3 emissions ranging from 0.13 to 0.34 g/bhp-hr [0.17 to 0.46 g/kW-hr] and from 0.44 to 0.97 g/mile [0.27 to 0.6 g/km] over the hot start UDDS compared to the SCR-equipped diesel vehicles due to NH 3 formation across the TWC. N 2 O emissions did not show consistent trends and were near/at the detection limits for a number of the vehicles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of NH 3 -fuel demands catalytic de-N 2 O unit for stack gas treatment. • Zn x Co 1− x Co 2 O 4 spinel catalysts were evaluated for low-temperature de-N 2 O. • T 50 of 203.3 °C and X N2O of 94.2 % at 250 °C were achieved when x = 0.73. • Zn induced the formation of oxygen vacancies, enhancing the resistance to O 2. • Zn strengthen the bond between Co and –NO species. The recent advancement of NH 3 -based fuel demands the development of catalysts that can decompose N 2 O at low temperatures and are stable against various inhibitors. Zn-doped cobalt spinel (Zn x Co 1− x Co 2 O 4) catalysts have demonstrated superior activity for N 2 O decomposition at low temperatures. However, their optimization and deactivation mechanisms with respect to Zn loading when inhibitors are present require further investigation. Herein, we reviewed the effects of Zn loading on catalysts at low temperatures without or with the presence of inhibitors (3 vol% O 2 , 6 vol% H 2 O, 200 ppm NO). The results showed that adding an appropriate amount of Zn into Co 3 O 4 spinel catalysts improves their N 2 O decomposition activity. The Zn-induced enhancement of the catalysts' redox properties, and reducibility was the underlying mechanism behind the activity promotion. The presence of structural defects created through the addition of Zn enhanced the catalyst's resistance to O 2. The deactivation by H 2 O and NO upon the addition of Zn could be correlated with the reduced availability of surface Co species and Co2+ as adsorption-active sites and the stronger bond of Co with –NO, respectively. This study underscores the importance of controlling the Zn loading as a bulk redox promoter in Zn x Co 1− x Co 2 O 4 spinel catalysts for practical applications. [ABSTRACT FROM AUTHOR]

Marginal seas play a critical role in the earth's systems as hotspots of microbially-mediated nitrogen (N) cycling. Meanwhile, human activities and global changes strongly impact this land-ocean boundary. Understanding the key N cycling processes and their climatic feedback is crucial for predicting the status of earth in the future and developing global N-driven physical-biogeochemical models. Although N cycling processes in China marginal seas have received great attention, a systematic analysis over a large geographical scale from estuaries to the deep ocean is still missing. This gap hinders us from concretely determining the sources and fate of N and predicting their responses to changing environments. This review compiles and re-analyzes historical data of source terms, encompassing N fluxes from riverine inputs and atmospheric deposition, as well as N 2 fixation. We also examine sinks related to sedimentary N loss processes (denitrification and anammox), internal N cycling processes (uptake and nitrification), short-lived N intermediates, and nitrous oxide, by considering rates, spatiotemporal variability, and environmental factors. Finally, we outline future research directions pertaining to marine N cycling in China marginal seas. [ABSTRACT FROM AUTHOR]

• Nitrous oxide misuse appears to promote the occurrence of thromboembolic events in a young population • Nitrous oxide misuse causes hyperhomocysteinemia, which is a risk factor for vascular events. • When facing a young patient presenting with thromboembolic effects, consumption of N 2 O should systematically be inquired • When facing a young patient presenting with thromboembolic effects, homocysteine level should be monitored • The primary method to prevent recurrences is to discontinue nitrous oxide use which often requires addiction treatment. [ABSTRACT FROM AUTHOR]