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Nitrous oxide (N 2 O) is a potent greenhouse gas that contributes significantly to the healthcare sector's carbon footprint. Pre-utilisation losses of N 2 O are up to 95%. Decommissioning manifolds can reduce these losses. Hospitals in our Greater London research network with at least one active N 2 O manifold were included in the Nitrous Oxide Manifold and Other Reduction of Emissions (NoMoreGas) study. N 2 O utilisation data were collected continuously over 5 days and extrapolated over a year, in addition to collecting procurement records from the preceding financial year. The primary outcome was the discrepancy between clinically utilised N 2 O and the quantity procured by hospitals, referred to as the 'N 2 O gap'. Secondary outcomes included anaesthetists' self-reported utilisation of N 2 O and their opinions on manifold decommissioning. Eighteen of 53 hospitals were included. In total, 6 487 200 L of N 2 O were procured with a median (IQR) of 304 200 (183 600–473 400) L per site. During the 5-day data collection period, sites utilised a median (IQR) of 501 (42–1409) L of N 2 O. Extrapolating over a year resulted in a median (IQR) annual utilisation of 36 573 (3066–102 857) L per site and a total of 1 175 348 L. This represented an estimated 18% of the N 2 O procured, suggesting pre-utilisation losses of 5 311 852 L. Among surveyed anaesthetists, 70% (n =309) reported using N 2 O within the previous year, with one-third (n =97) using it once a week or more. There was widespread support for decommissioning manifolds. Consistent with other reports, the data demonstrate a substantial discrepancy between the quantities of N 2 O procured and utilised clinically, indicative of significant pre-utilisation losses. Our findings support the decommissioning of N 2 O manifolds for environmental and economic benefits. [ABSTRACT FROM AUTHOR]

A systematic review of clinical trials confirms that including nitrous oxide in the gas mixture for general anaesthesia has minor short-term benefits and does not impact most patient safety outcomes. However, no risk-benefit analysis of nitrous oxide should ignore its known environmental effects. If continued nitrous oxide use is supported, strategies to minimise and monitor the contribution of medical nitrous oxide to global warming are vital. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N 2 O) is a common adjuvant to general anaesthesia. It is also a potent greenhouse gas and causes ozone depletion. We sought to quantify the influence of N 2 O as an adjuvant to general anaesthesia on postoperative patient outcomes. We searched Medline, EMBASE, and Cochrane Central for works published from inception to July 6, 2023. RCTs comparing general anaesthesia with or without N 2 O were included. Risk ratios (RRs) and standardised mean differences (SMDs) were calculated, along with 95% confidence intervals (CIs), using a random-effects model. Outcomes were derived from the Standardised Endpoints for Perioperative Medicine (StEP) outcome set. Primary outcomes were mortality and organ-related morbidity, and secondary outcomes were anaesthetic and surgical morbidity. Of 3305 records, 179 full-text articles were assessed, and 71 RCTs, totalling 22 147 patients, were included in the meta-analysis. Addition of N 2 O to general anaesthesia did not influence postoperative mortality or most morbidity outcomes. N 2 O increased the incidence of atelectasis (RR 1.62, 95% CI 1.24 to 2.12) and postoperative nausea and vomiting (RR 1.27, 95% CI 1.15 to 1.40), and decreased intraoperative opioid consumption (SMD –0.19, 95% CI –0.35 to –0.04) and time to extubation (MD –2.17 min, 95% CI –3.32 to –1.03 min). N 2 O did not influence postoperative mortality or most morbidity outcomes. Considering the environmental effects of N 2 O, these findings confirm that current policy recommendations to limit its use do not affect patient safety. PROSPERO CRD42023443287. [ABSTRACT FROM AUTHOR]

To establish if highly eutrophic lakes generate higher N2O emissions than non-eutrophic aquatic environments in New Zealand, we monitored N2O emissions from hypereutrophic Lake Horowhenua, near Levin, and the oligotrophic Turitea dam reservoir, near Palmerston North, used as control. Based on more than 12 months of monitoring data, N2O emissions from Lake Horowhenua were estimated to −0.05–6.93 mg-N2O·m−2·d−1 (n = 66), with a median of 0.30 mg-N2O·m−2·d−1. At the Turitea reservoir, N2O emissions ranged from −0.02–1.51 mg-N2O·m−2·d−1 with a median of 0.15 mg-N2O·m−2·d−1 (n = 53). No correlation was found between N2O emissions and the water temperature, sunlight, dissolved oxygen, nutrient concentration or chlorophyll a. When extrapolating the emission data to NZ, we estimated NZ lakes could release 83 kt of N2O as CO2eq each year, which is low in comparison to other sectors such as agriculture. Following the Intergovernmental Panel on Climate Change methodology, the N2O emission factor for Lake Horowhenua was estimated at 0.0019 kg N2O-N per kg of N-NO3− input into the lake. [ABSTRACT FROM AUTHOR]

The article discusses the consensus on decommissioning piped nitrous oxide from UK and Ireland operating theatre suites due to its inefficiency and environmental impact as a potent greenhouse gas. The joint statement by various medical associations calls for a shift to more efficient methods of supply and highlights the financial and environmental benefits of decommissioning piped nitrous oxide. The article emphasizes the importance of addressing the environmental impact of medical practices and the need for healthcare institutions to prioritize sustainability without compromising patient care. [Extracted from the article]

Biochar is a carbon-rich material produced through the pyrolysis of organic biomass. Its unique properties make it a versatile asset in agricultural and environmental management. This review paper provides scientific insights into how biochar affects soil's physical, chemical, and biological properties. It then discusses how these changes can impact crop growth and yield, addressing a key concern for farmers while also considering the potential for biochar to mitigate greenhouse gas (GHG) emissions such as carbon dioxide (CO2), Nitrous oxide (N2O), and methane (CH4), which is of public interest. Additionally, it examines the costs and benefits associated with biochar use, aiming to guide its adoption and suggest future research directions in agricultural applications. Biochar incorporation improves soil properties by enhancing structure, water retention, aeration, nutrient availability, and microbial activity. Different processes impact the effects of biochar on soil, plants, and agricultural systems, influenced by factors like biochar type, soil type, and application rate. Understanding the interaction of these elements, especially over the long term, is vital for promoting the widespread use of biochar in agriculture. Moreover, assessing the economic benefits and costs of biochar in each region is key to convincing farmers to adopt this practice. [ABSTRACT FROM AUTHOR]

The paper has been suggested by the following observations: (1) the atmospheric growth rate of carbon dioxide concentration is smaller than that ascribed to the emission of fossil-fuel combustion and (2) the fossil-fuel reserves are finite. The first observation leads to a simple dynamic model, based on the balance of CO2 land/ocean absorption and anthropogenic emissions, only limited by the depletion of fossil-fuel reserves, in a business-as-usual scenario. The second observation suggests of projecting the past CO2 emissions to the future, by constraining emissions to the limit of reserve availability. Similar projections are available in the literature, but either driven by heuristics or by complex simulation packages. The paper provides a simple and formal method only driven by historical data, their uncertainty and simple models. The method aims to provide CO2 concentration projections, which being constrained by fossil-fuel finite reserve may be in principle employed as bounds to forecasting exercises. The time–invariant dynamics of the land/ocean absorption is the simplification of a more complex set of equations describing carbon dioxide exchange between different reservoirs. Contribution of other greenhouse gases like methane and nitrous oxide has been neglected, since their emissions cannot be projected with the paper methodology. Comparison with recent profiles of the Intergovernmental Panel on Climate Change (IPCC) confirms that the finite-reserve projections of the fossil fuel emissions is close to those of a moderate Shared Socioeconomic Scenario (SSP) like SSP2-4.5—a result in agreement with other authors—but also reveals the limits of the simplified model, when extending the tuned dynamics of the recent mean CO2 exchanges to long-term future. The limits derive from linearity, time invariance, and aggregation assumptions, which allow a more complex model of CO2 exchanges to be simplified and tuned on experimental data. [ABSTRACT FROM AUTHOR]

Background: Pharmacological methods, specifically sedatives, have gained popularity in managing the behavior of children during dental appointments. Aim: The aim of this study was to compare 1 m/kg intranasal dexmedetomidine, 0.3 mg/kg intranasal midazolam, and nitrous oxide in evaluating the level of sedation, behavior of the child, onset of sedation, physiologic signs, and adverse effects. Materials and Methods In this cross-over trial, 15 children aged 6–8 years were randomized to receive intranasal atomized dexmedetomidine, intranasal atomized midazolam, and inhalation nitrous oxide at three separate visits. After administering the sedative agent, a single pulpectomy was performed during each appointment, and the outcomes were recorded. The washout period between each visit was 1 week. Results: All three sedative agents were equally effective in controlling overall behavior. Dexmedetomidine showed lower sedation level scores (agitated; score 9) than the other groups. There was a statistically significant difference in the onset of sedation, with dexmedetomidine having the longest onset of 36.2 ± 9.47 min. Coughing and sneezing were predominantly observed after administration of intranasal midazolam. Oxygen saturation levels were statistically lower in the intranasal midazolam group during local anesthesia administration and post-treatment. Conclusion: 0.3 mg/kg intranasal midazolam is as effective as nitrous oxide sedation for controlling behavior and providing adequate sedation in pediatric dental patients. However, 1 m/kg dexmedetomidine did not provide the same level of sedation and had a significantly longer onset. 0.3 mg/kg intranasal midazolam is an effective alternative to nitrous oxide sedation in anxious children.

Feeding rate is an important factor influencing the carbon and nitrogen input and greenhouse gas emission from aquaculture systems. However, the quantitative relationship between feeding rates and GHG emissions is still poorly understood. In this study, we conducted a laboratory-scale experiment to examine the impact of feeding rate (0%, 2%, 4%, 6%, and 8%) on the CH4 and N2O emissions from a pond rice-fish co-culture system. The results showed that the total amount of CH4 emission did not significantly differ when the feeding rate was no more than 6%, but increased more than four times when the feeding rate reach to 8%. The amount of N2O emission showed a linearly increasing trend with the feeding rate. The emission factors of CH4 and N2O was significantly higher for 8% feeding rate than other feeding rates. The variation of CH4 emission was primarily attributed to the ratio of mcrA/pmoA in the sediment and the contents of biological oxygen demand (COD) and dissolved oxygen (DO) in the water; and the variation of N2O was primarily affected by the available nitrogen in the water and sediment and the content of DO in the water. The overall emission of CH4 and N2O showed an exponential relationship with feeding rate. The total yields of fish and rice did not continuously increase when the feeding rate exceeded 4%. The lowest emission intensity per unit yield was reached at the feeding rate of 2.99%. These results can provide a reference for the determination of low-carbon feeding strategy for pond rice-fish co-culture system. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) emissions are a serious global issue, with substantial evidence indicating that hydroclimate processes significantly contribute to these emissions. Forests, covering one-third of global land, are key in the water cycle and influence hydroclimate processes, which vary with climate, latitude, and forest types. The role of hydroclimate in regulating global forest N2O emission remains largely unknown. Our global analysis shows that hydroclimate factors dominate the latitudinal gradient of forest N2O fluxes, which decrease with latitude. N2O fluxes are highest in tropical forests, followed by temperate and boreal forests. Hydroclimate factors contribute 78.2% to N2O fluxes, while soil factors contribute 21.8%. Our results urgently call for future studies to investigate the relationship between N2O flux and hydroclimate factors like radiation, evapotranspiration, and vapor pressure deficits. Collectively, these findings highlight hydroclimate significant impact on N2O emissions and suggest incorporating these factors into predictive models for greater accuracy. [ABSTRACT FROM AUTHOR]

Background Aims Methods Results Conclusion Incorporation of cover crop (cc) shoot and root biomass can have different effects on nitrogen (N) dynamics and the transformation of soil‐derived N and cc N.The objective was to determine the effects of different ccs, cc compartments (roots and shoots), and pretreatment of cc biomass (fresh vs. dried) on mineralization processes and on the transformation of soil and cc N following incorporation into a silty loam soil.Soil columns with incorporated 15N‐labeled root and shoot biomass of two cc species (winter rye and oil radish) and different pretreatments (dried and fresh) were incubated for 70 days at a constant temperature and soil moisture (8°C, 40% water‐filled pore space). Carbon and N transformation dynamics were determined repeatedly, distinguishing between N originating from cc biomass and from soil.Net CO2 emission was related to the amount of soluble cell components added with ccs. Net N mineralization was negatively related to the C:N ratio of cc biomass. The incorporation of dried cc biomass caused higher initial soil respiration and N immobilization than fresh biomass. All treatments with cc incorporation showed increased N2O emission. Emitted N2O‐N consisted mainly of cc N (55%–57%) in treatments with fresh shoot biomass, whereas soil N was the main source of N2O (75%) in the treatment with fresh oil radish roots. Recovery of cc 15N was affected by crop compartment and pretreatment. At the end of the incubation, it was 17.5%–42.3% in soil NO3−, 0.1%–8.1% in microbial biomass N, and less than 0.23% of cc N was found in cumulative N2O emission.The incorporation of cc roots and shoots had different effects on N mobilization and immobilization processes and on the partitioning of cc N. These processes can be influenced significantly by pretreatment of the added plant biomass (dried vs. fresh). [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]

Introduction: During child dental treatment, different behavior management techniques (BMTs) are applied and it is important to understand the possible discomfort in the operator. Objective: The present systematic review aimed to evaluate the acceptability of dental students and professionals concerning BMTs applied with paediatric dentistry patients. Materials and Methods: A systematic search was conducted, following the PEOS strategy: Population (P) – dental students/professionals (S); Exposure (E) – BMTs preconized by the American Academy of Paediatric Dentistry, Outcome (O) – proportion of BMT acceptance; and Study design (S) – observational studies based on data from PubMed, Scopus, Web of Science, BVS (Lilacs/BBO), Cochrane, and Open Grey databases up to September 2021. The eligible studies were submitted to data extraction and to the evaluation of methodological quality, using the Joanna Briggs Institute Critical Appraisal Tool. The certainty of evidence was evaluated by GRADE. Results: The search retrieved 710 articles; a total of 21 fulfilled the eligibility criteria and were used for qualitative analysis. Among the undergraduate students and dentists, the most accepted techniques were tell‐show‐do and positive reinforcement, while paediatric dentists preferred the tell‐show‐do technique and dental professionals with graduate degrees preferred sedation using nitrous oxide and positive reinforcement. The least accepted technique was protective stabilization. Seven students presented a low risk for bias, while 14 presented a high risk. The certainty of evidence was classified as very low. Conclusion: Although the basis of available certainty of evidence is scarce and with a considerable risk for bias, it is still possible to conclude that the more accepted techniques were based on communication. [ABSTRACT FROM AUTHOR]

Background: Remimazolam is an ultrashort-acting benzodiazepine. Few studies have evaluated the effects of remimazolam-based total intravenous anesthesia (TIVA) on emergence agitation (EA). This study aimed to compare the incidence and severity of EA between TIVA using remimazolam and desflurane. Methods: This prospective randomized controlled study enrolled 76 patients who underwent nasal surgery under general anesthesia. Patients were randomized into two groups of 38 each: desflurane-nitrous oxide (N2O) (DN) and remimazolam-remifentanil (RR) groups. The same protocol was used for each group from induction to emergence, except for the use of different anesthetics during maintenance of anesthesia according to the assigned group: desflurane and nitrous oxide for the DN group and remimazolam and remifentanil for the RR group. The incidence of EA as the primary outcome was evaluated using three scales: Ricker Sedation-Agitation Scale, Richmond Agitation-Sedation Scale, and Aono's four-point agitation scale. Additionally, hemodynamic changes during emergence and postoperative sense of suffocation were compared. Results: The incidence of EA was significantly lower in the RR group than in the DN group in all three types of EA assessment scales (all P < 0.001). During emergence, the change in heart rate differed between the two groups (P = 0.002). The sense of suffocation was lower in the RR group than in the DN group (P = 0.027). Conclusions: RR reduced the incidence and severity of EA in patients undergoing nasal surgery under general anesthesia. In addition, RR was favorable for managing hemodynamics and postoperative sense of suffocation. [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]

The aim of this study was to explore the effect of biochar on N2O emissions in soils with different pH levels. Soils with five pH levels (4.0, 5.1, 5.8, 6.6, and 7.2) were incubated in two conditions, with 0% biochar (CK) and 1% biochar (BC), for 23 days. N2O emissions were measured at nine time points, and soil chemical properties, AOA-amoA, AOB-amoA, nirK, nirS, and nosZ, were analyzed. Partial least squares path modelling (PLS-PM) was used to assess the effect of nitrification and denitrification pathways on potential N2O emissions. The results showed that biochar reduced N2O emissions in highly acidic soil (pH 4.0) but increased emissions in soils with pH values ranging from 5.1 to 7.2. In highly acidic soils, decreased N2O emission was associated with increased soil pH (p < 0.05) and decreased dissolved organic carbon content (p < 0.05), leading to higher nosZ gene abundance (p < 0.05). Meanwhile, in acidic to neutral soils, biochar application increased soil pH (6.6–11.7%), dissolved organic nitrogen (5.9–29.5%), dissolved organic carbon (8.6–41.0%), stimulated AOB-amoA, nirK, nirS gene abundance (p < 0.05), and thus increased N2O emissions. The results verified the influence of nitrification and denitrification genes on N2O production in soils with different pH values. In conclusion, biochar had different effects on N2O emissions based on soil pH, highlighting the need to consider pH when using biochar to mitigate N2O emissions in subtropical citrus orchards. [ABSTRACT FROM AUTHOR]

This article discusses the ethical implications of removing Entonox® from labor wards as part of a strategy to mitigate the climate crisis. The authors argue that while the greenhouse gas and ozone-depleting effects of nitrous oxide are well-known, it is premature to remove it without first addressing wastage and exploring alternative strategies. They emphasize the importance of considering patient care, staff safety, and the impact on vulnerable groups when making decisions about sustainability in healthcare. The authors also call for a broader approach to sustainability that goes beyond carbon counting and includes considerations of health inequality and social justice. [Extracted from the article]

Aims: Nitrous oxide (N2O) plays an important role in global climate change. Plant expansion can alter soil nutrient cycling and greenhouse gas (GHG) fluxes but the effects of fine root litter mixing from plant expansion on litter decomposition, nutrient cycling, and GHG fluxes are poorly understood. Methods: To evaluate the impacts of fine root litter mixing from plant expansion on GHG budgets, we conducted an in situ study over sixteen months in Japanese cedar (Cryptomeria japonica) plantations experiencing moso bamboo (Phyllostachys edulis) expansions. Litter decomposition and N2O production were quantified in a full-factorial complete-randomized design by comparing fine root litter of Japanese cedar, moso bamboo or their mixtures, with or without nitrogen (N) addition. Results: We found that litter mixing accelerated decomposition, demonstrating a synergistic non-additive effect (19% increase in mass loss). This might have accelerated release of chemicals that inhibit microbial activities because litter mixtures had lower microbial biomass. Soil N2O emissions in the mixed litter treatment were 16.8% and 24.4% lower than those with only cedar or bamboo litter, respectively. N deposition promoted mass loss of mixed litter (28% increase in mass loss) and increased N2O emissions by 36.7%, 60.6% and 33.6% from cedar, mixed and bamboo litter treatments, respectively. Conclusion: The expansion of moso bamboo promotes the return of soil nutrients, reduces N2O emissions, and potentially mitigates GHG emissions. However, with increasing N deposition in the future, moso bamboo expansion will likely contribute to global warming. [ABSTRACT FROM AUTHOR]

Nitrous oxide is used as an anaesthetic and analgesic agent in the medical setting and is known to cause raised intracranial pressure. The use of nitrous oxide recreationally for the drug's euphoric and relaxant properties has been linked to multiple neurological and psychiatric sequelae including neuropathy, myelopathy, and psychosis. We describe a case of a young person who declared heavy nitrous oxide use resulting in vision-threatening papilloedema secondary to raised intracranial pressure. He underwent emergency lumbar drainage alongside high-dose acetazolamide and parenteral vitamin B12 injections. To our knowledge, there have yet to be other reports of cases where heavy nitrous oxide use has caused secondary pseudotumor cerebri syndrome. [ABSTRACT FROM AUTHOR]

Nitrous oxide, an inhalational anaesthetic, is popular with adolescents worldwide as an accessible recreational drug which induces a euphoric effect. However, chronic abuse leads to serious complications such as myeloneuropathy and bone marrow suppression by inactivation of vitamin B12. A 17-year-old girl presented with nitrous oxide-induced myeloneuropathy. She reported chronic nitrous oxide inhalation for 10 months and was admitted to the emergency department on account of repeated falls for 2 weeks. She also had ascending paraesthesia in both legs and urinary incontinence. Neurological examination demonstrated bilateral lower extremity weakness [motor power: proximal muscles 4/5, plantar flexion and extensor hallucis longus (EHL) 3/5], decreased sensation, proprioception and vibration of the lower extremities. Deep tendon reflexes were absent in the ankles and knees. Laboratory results demonstrated mild anaemia [Hb 11.2 g/dL (12.0–16.0), haematocrit 35.4% (36–50), MCV 89.4 fl (78–102)] with significant hypersegmented neutrophils in a peripheral blood smear. Serum vitamin B12 was 340 pg/mL (197–771), but serum homocysteine was increased at 65.8 µmol/L (5–15). A nerve conduction study was prolonged, and F-waves were absent from the bilateral perineal and tibial nerves, indicating diffuse demyelinating motor polyneuropathy. Magnetic resonance imaging of the whole spine demonstrated faint T2 hypersignal intensity and an inverted V-shape appearance at the posterior column of the upper thoracic cord (around T2–T6), a pathognomonic sign of vitamin B12 deficiency or subacute combined degeneration of the nitrous oxide-induced myeloneuropathy. A 7-day course of 1000 µg cyanocobalamin was given intramuscularly, followed by weekly doses for 4 weeks. Supplements of daily oral vitamin B1, B6 and B12 (65 µg vitamin B12) were administered, along with rehabilitation. At the 6-months outpatient follow-up, there were a few residual neurological abnormalities: weakness of the left EHL (grade 4/5) and an absent deep tendon reflex in the left ankle. This case emphasises the significant health consequences of chronic abuse of nitrous oxide, myeloneuropathy and megaloblastic anaemia, by inactivation of vitamin B12. The myelopathy is noticeably improved by cyanocobalamin. Abbreviations: EHL: extensor hallucis longus; MRI: magnetic resonance imaging; NCS: nerve conduction study [ABSTRACT FROM AUTHOR]

Four new tirucallane-type triterpenoids, polystanins H–K (1–4), were obtained from the stems and leaves of Aphanamixis polystachya. Their structures were elucidated by analysis of the spectroscopic data and comparison with literature data. Compounds 1 and 2 showed week inhibitory effects against NO production in LPS-stimulated RAW264.7 cells. All the isolates were investigated for their antifungal activities against drug-resistant Candida albicans. [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]

Effective nitrogen fertilizer management is crucial for reducing nitrous oxide (N2O) emissions while ensuring food security within planetary boundaries. However, climate change might also interact with management practices to alter N2O emission and emission factors (EFs), adding further uncertainties to estimating mitigation potentials. Here, we developed a new hybrid modeling framework that integrates a machine learning model with an ensemble of eight process‐based models to project EFs under different climate and nitrogen policy scenarios. Our findings reveal that EFs are dynamically modulated by environmental changes, including climate, soil properties, and nitrogen management practices. Under low‐ambition nitrogen regulation policies, EF would increase from 1.18%–1.22% in 2010 to 1.27%–1.34% by 2050, representing a relative increase of 4.4%–11.4% and exceeding the IPCC tier‐1 EF of 1%. This trend is particularly pronounced in tropical and subtropical regions with high nitrogen inputs, where EFs could increase by 0.14%–0.35% (relative increase of 11.9%–17%). In contrast, high‐ambition policies have the potential to mitigate the increases in EF caused by climate change, possibly leading to slight decreases in EFs. Furthermore, our results demonstrate that global EFs are expected to continue rising due to warming and regional drying–wetting cycles, even in the absence of changes in nitrogen management practices. This asymmetrical influence of nitrogen fertilizers on EFs, driven by climate change, underscores the urgent need for immediate N2O emission reductions and further assessments of mitigation potentials. This hybrid modeling framework offers a computationally efficient approach to projecting future N2O emissions across various climate, soil, and nitrogen management scenarios, facilitating socio‐economic assessments and policy‐making efforts. [ABSTRACT FROM AUTHOR]

Continental groundwaters are commonly enriched in nitrous oxide (N2O) and methane (CH4), which can discharge into the coast. The contribution of this diffuse source to coastal N2O and CH4 emissions largely depends on the biogeochemical processes of coastal aquifer exit zones, known as subterranean estuaries. Here, we study the role of subterranean estuaries in modulating N2O and CH4 exports toward the coast. The two studied subterranean estuaries are located at Panxón and Ladeira beaches (Ría de Vigo, NW Iberian Peninsula) and had opposite oxygenation at their interior. Groundwater‐borne N2O was detected in the oxygenated subterranean estuary of Panxón Beach, although denitrification attenuated N2O before porewater was discharged into the coast. An N2O hotspot was detected at about 50 cm depth in this subterranean estuary, characterized by the presence of nitrate under suboxic conditions. This N2O also seems to be consumed along the flow path before discharging into the coast. The anoxic subterranean estuary of Ladeira Beach completely removed groundwater‐borne N2O. Yet, nitrification within its suboxic upper saline plume produced and exported N2O toward the coast, hiding the role of this subterranean estuary as an N2O sink. The anoxic subterranean estuary exported CH4 toward the coast. This CH4 was not sourced by continental groundwater, hence it was produced in situ fuelled by the accumulation of organic matter within the beach. The suboxic upper saline plume in Ladeira Beach and the oxygenated subterranean estuary of Panxón Beach acted as CH4 sinks. [ABSTRACT FROM AUTHOR]

Background: Nitrous oxide use is shifting from general anesthesia to sedation and pain control. Interest in novel uses of nitrous oxide in psychiatry is also growing. Thus, understanding the consequences of using nitrous oxide remains relevant. Previous quantitative research might not have fully captured the whole spectrum of nitrous oxide, whereas qualitative analysis can provide a more comprehensive description. This qualitative study aims to describe the subjective experiences of nitrous oxide use in healthy volunteers who have no prior history of recreational substance misuse. Methods: Twenty healthy male volunteers inhaled 50% nitrous oxide for 20 min. Females were excluded due to higher incidence of nausea with nitrous oxide. Afterwards, all participants answered an open‐ended question about their experiences during sedation. The answers were then analyzed with inductive qualitative content analysis to identify emergent subcategories, categories, and overarching themes. Results: We identified two themes: nitrous oxide is mind‐altering and produces sensory overload. The mind‐altering properties were represented by dreamlike states and heightened emotions. Dreamlike states comprised changes in consciousness and scary, bizarre, or transcendental dreams. Pleasant dreams were not reported. Heightened emotions included euphoria, anxiety, and fear of losing control. Sensory overload consists of distorted perception, bodily sensations, and a heightened sense of surroundings. Conclusions: Experiences under nitrous oxide sedation are extremely variable and not always pleasant. These findings can improve our understanding of the likes/dislikes of patients undergoing nitrous oxide sedation. Further qualitative studies should focus on the experiences of other groups, such as children or women in labor. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) emissions are known to contribute to global climate change. A two-year field study on Kentucky bluegrass (Poa pratensis L.) evaluated cultivation practices and fertilizer use on GHGs. The presence of urea and hollow-tine aerification resulted in the highest soil carbon dioxide (CO2) emissions. No significant differences between soil methane (CH4) flux were observed based on fertilizer; however, in 2014 the verticutting cultivation treatment fluxed significantly more soil CH4 than the uncultivated control. Results showed no significant differences in soil nitrous oxide (N2O) in 2013; however, in 2014, both fertilizer and cultivation practices showed significant differences between treatments, with the urea and the hollow-tine treatments fluxing significantly more soil N2O. The hollow-tined plots produced the greenest turf in 2013, followed by the uncultivated control and the verticutted treatment. In 2014, both the hollow-tine and the uncultivated control produced the greenest turf, followed by the verticutted treatment. The hollow-tined and uncultivated control treatments had significantly higher turfgrass quality than the verticutted treatment. The verticutted urea treatment was above acceptable levels (>6.0) for turfgrass quality following all cultivation events. The results show cultivation practices can be identified that reduce GHG emissions while maintaining turfgrass quality and color. [ABSTRACT FROM AUTHOR]

Climate change mitigation requires creative solutions to reduce greenhouse gases (GHG). Little research has been performed on GHG emissions from shaded turfgrass systems, resulting in a lack of best management practice (BMP) development. The aim of this research was to investigate the soil flux of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) as impacted by shade [shade (98.8%) versus sun (100%)] and differing sources (fast- versus slow-release) and rates (147 versus 294 kg ha−1 yr−1) of nitrogen (N) fertilizers on creeping bentgrass putting greens. The results show that emissions of soil CO2 and soil N2O are significantly lower in shaded plots versus sunny plots. The presence of N fertilizer significantly increased soil CO2 emissions over unfertilized plots. Quick-release N fertilizer fluxed significantly more soil N2O than the slow-release N fertilizers. Turfgrass color was significantly higher on the sunny green versus the shaded green except in late summer. Turfgrass quality was significantly higher for the shaded green versus the sunny green. Milorganite improved turfgrass quality whereas urea decreased turfgrass quality due to fertilizer burn. When N is needed to improve turfgrass color and quality, the use of slow-release N sources should be a BMP for shaded greens. [ABSTRACT FROM AUTHOR]

The production of statice (Limonium sp.) plants with higher ploidy through induction of whole-genome duplication (WGD) via the spindle disrupter nitrous oxide (N2O) was examined as a strategy to increase the germplasm diversity of the species. Furthermore, the impact of the resulting ploidy changes on the morphological features of the progeny was examined. Intraspecific crosses between diploid plants of Limonium sinuatum (L.) Mill and L. perezii (Stapf) Hubb. were conducted daily for seven consecutive days, with subsequent exposure to N2O. Within the resulting progeny, between 16% and 35% of plants were polyploid when N2O was applied between one and four days after pollination. A comparative analysis between diploid and tetraploid progeny was conducted, using a selection of 10 L. sinuatum (5 diploids and 5 tetraploids) and 7 L. perezii (4 diploids and 3 tetraploids) genotypes. The results revealed differences between tetraploids and their diploid counterparts for most of the evaluated characteristics. Tetraploid plants of L. sinuatum and L. perezii exhibited pollen grains 1.5 times larger in plan area; the leaves and main floral stem diameter were 1.2 and 1.5 times thicker for L. sinuatum and L. perezii, respectively, the guard cell length was 1.4 times greater for both species, while the stomatal density was 0.6 times lower for L. perezii and 0.8 for L. sinuatum. The leaf area and main floral stem wings were affected by the ploidy increase only for L. sinuatum. In this regard, tetraploid plants of L. sinuatum displayed leaves 1.8 times bigger and main floral steam wings 2.4 times wider in comparison to diploid plants. In conclusion, the production of tetraploid Limonium plants using N2O shortly after pollination creates new diversity for breeding. These findings underscore the potential for leveraging polyploidy as a strategy to enhance desirable traits in Limonium species. [ABSTRACT FROM AUTHOR]

A three-year field experiment was carried out to investigate the methane (CH4) and nitrous oxide (N2O) emissions and calculate the global warming potential (GWP) according to all energy input in response to the nitrogen (N) rate in the typical rice-wheat rotation system in Jiangsu, China. Four N treatments, including R220W180 (local practice), R220W140 (cutting 10% total N in wheat season), R180W180 (cutting 10% total N in rice season) and R180W140 (cutting 20% total N in rice and wheat seasons separately), were designed in the study. Results showed that annual CH4 emission was decreased by 25.7% in response to cutting 20% N, which was ascribed to the 24.6% reduction of CH4 emission in rice season (P < 0.05) compared to local practice. The mitigation of N2O emissions in R220W140 and R180R180 treatments contributed to the 8.5% and 15.7% decrease in annual N2O emission, which was the 23.5% decrease in cutting 20% N treatment compared to local practice, respectively. Specifically, under the same amount of N rate condition (10% N cutting), the transfer N from rice season (R220W140) to wheat season (R180W180) led to the 8.5% increase in N2O emission (P < 0.05). In the end, the cutting of 20% N decreased GWP and yield-scale GWP by 19% and 17%, which mainly originated from CH4 and N2O emissions. However, cutting N did not significantly decrease grain yield (P > 0.05). These results suggested that the 180 kg N/ha for rice and 140 kg N/ha for wheat in one rotation season were the beneficial N rate to achieve the co-benefit of yield and GWP in the typical rice-wheat rotation system in Jiangsu, China. [ABSTRACT FROM AUTHOR]

The demand for biomass energy production in the Philippines has led to substantial rice husk ash (RHA) generation. We combined alternate wetting and drying (AWD) and varying RHA rates (10, 20, and 30 t ha–1) to evaluate the yield, water productivity (WP), and greenhouse gas (GHG) emissions in paddy rice for four cropping seasons (CS). We compared these treatments with continuous flooding (CF) and no RHA as controls. The RHA decreased N2O emissions by 8–22%, in the order of RHA30 > RHA20 > RHA10 relative to the control. The AWD had a marginal effect (P < 0.10) on CH4 emissions, with a 10% reduction relative to CF. While yields did not differ among treatments, AWD saved 39% water, and WP increased by 0.56 kg m–3 relative to CF. A significant interaction (P < 0.05) among water, RHA, and CS on N2O emissions was associated with rice stubble management in the first CS just after the harvest of the previous crop (dry incorporation), while the other seasons incorporated stubbles during wetland preparation. Although the highest RHA rate was likely to increase N2O emissions under AWD conditions, the global warming potential (GWP) was still significantly lower (P < 0.05) in the first CS in either water management by up to 15 times lower compared to other CS at all RHA rates. Our results indicated that the primary RHA effects mitigated N2O emissions, while AWD had only marginal effects on CH4 emissions but maintained grain yield under our experimental conditions. The low total GWP in the first CS suggests that the additional mitigation measures of RHA application and water management need to be associated with the proper management of rice stubbles first. [ABSTRACT FROM AUTHOR]

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In the framework of the RECCAP2 initiative, we present the greenhouse gas (GHG) and carbon (C) budget of Europe. For the decade of the 2010s, we present a bottom‐up (BU) estimate of GHG net‐emissions of 3.9 Pg CO2‐eq. yr−1 (using a global warming potential on a 100 years horizon), which are largely dominated by fossil fuel emissions. In this decade, terrestrial ecosystems acted as a net GHG sink of 0.9 Pg CO2‐eq. yr−1, dominated by a CO2 sink that was partially counterbalanced by net emissions of CH4 and N2O. For CH4 and N2O, we find good agreement between BU and top‐down (TD) estimates from atmospheric inversions. However, our BU land CO2 sink is significantly higher than the TD estimates. We further show that decadal averages of GHG net‐emissions have declined by 1.2 Pg CO2‐eq. yr−1 since the 1990s, mainly due to a reduction in fossil fuel emissions. In addition, based on both data driven BU and TD estimates, we also find that the land CO2 sink has weakened over the past two decades. A large part of the European CO2 and C sinks is located in Northern Europe. At the same time, we find a decreasing trend in sink strength in Scandinavia, which can be attributed to an increase in forest management intensity. These are partly offset by increasing CO2 sinks in parts of Eastern Europe and Northern Spain, attributed in part to land use change. Extensive regions of high CH4 and N2O emissions are mainly attributed to agricultural activities and are found in Belgium, the Netherlands and the southern UK. We further analyzed interannual variability in the GHG budgets. The drought year of 2003 shows the highest net‐emissions of CO2 and of all GHGs combined. Plain Language Summary: We have synthesized the European budgets of carbon and the greenhouse gases (GHG) carbon dioxide, methane and nitrous oxide. This synthesis includes estimates of direct emissions from fossil fuel burning, industrial production, waste management and agriculture, as well as of sources and sinks in the terrestrial biosphere. Summing up the sources and sinks of the three GHGs, we estimate for the decade of the 2010s an average annual net‐emission of 3.9 billion tons of carbon dioxide equivalents. These net‐emissions are dominated by carbon dioxide from fossil fuel emissions (4.1 billion tons of carbon dioxide). In contrast, the terrestrial biosphere acts as a net sink of carbon dioxide, the effect of which is only partly counterbalanced by net emissions of methane and nitrous oxide. The net‐effect of the terrestrial biosphere's GHG budget is a sink of 0.9 billion tons of carbon dioxide equivalents per year. Over the last three decades, European GHG emissions have declined by 1.2 billion tons carbon dioxide equivalents per year, mainly due to reductions in fossil fuel emissions. However, the sink capacity of the terrestrial biosphere has diminished since the 2000s. Key Points: We provide a bottom‐up estimate of CO2, CH4, N2O emissions of 3.9 Pg CO2‐eq. yr−1 over Europe, 2010–2019Terrestrial ecosystems acted as a greenhouse gas net sink of 0.9 Pg CO2‐eq. yr−1, dominated by CO2 sinkNet‐greenhouse gas emissions decreased by ∼1/4 since the 1990s, but land carbon sink is weakening since the 2000s [ABSTRACT FROM AUTHOR]

Turfgrass systems hold significant climate change mitigation value, but their management often negates the beneficial effects due to the intense adoption of external inputs. The research objective in this paper was to assess the nitrogen fertilization rate able to maintain the ideal esthetic characteristics of Zoysia turfgrass, reducing the environmental impacts associated with greenhouse gas (GHG) emissions. A two-year open field experiment was conducted. Nitrogen was added to the soil at six rates (0, 50, 100, 150, 200, and 250 kg ha−1). The GHG emissions were monitored using a portable gas analyzer and the static chamber methodology. Cumulative environmental impacts were calculated from the inclusion of CO2, CH4, and, N2O using the Global Warming Potential (GWP). The quality assessment of the turf was assessed through a visual and instrumental approach. Higher CO2 and N2O fluxes were linked to high nitrogen rates, ranging from 83.55 to 87.50 and from 0.046 to 0.047 g N-N2O ha−1 day−1 for 200 and 250 kg N ha−1, respectively. CH4 emissions were not correlated to nitrogen rates. Higher GWP impacts were linked to high N rate treatments. A rate of 100 kg N ha−1 is recommended as the best strategy to reduce GHG emissions while maintaining high turf quality. [ABSTRACT FROM AUTHOR]

Arteriovenous malformations (AVMs) are abnormal connections between arteries and veins that bypass the capillary system. Among AVMs, uterine ones are very rare, and it is not possible to have clear data on their incidence, as a good part of the patients remain clinically asymptomatic. Uterine AVMs consist of abnormal communications between branches of the uterine artery and the myometrial venous plexus. They can lead to significant bleeding, resulting in severe anemia and the need for transfusions. Both medical and surgical therapeutic approaches are described in the literature; as regards surgical treatments, the hysteroscopic excision of the endometrial mass represents a conservative and minimally invasive approach. However, there are no reported cases in the literature of AVMs treated using a hysteroscopic approach under local anesthesia and in an office setting. In this article, we propose the case of a young woman diagnosed with postpartum uterine AVM, treated using a 16 Fr miniresectoscope (GUBBINI system; Tontarra Medizintechnik®, Tuttlingen, Germany) in an office setting with a pain control protocol (pericervical infiltration and nitrous oxide via bucconasal mask). No complications occurred, and the woman was discharged immediately after the procedure. Finally, the patient was asked how tolerable and acceptable the procedure was compared to expectations; the woman defined the procedure as very bearable and well tolerated. The outpatient treatment, with an adequate pain control protocol, proved to be less invasive for the woman, did not require narcosis and hospital admission, but was equally therapeutic and effective compared to the treatment performed in the operating room. [ABSTRACT FROM AUTHOR]

\nIntroduction: Vitamin B12 deficiency is primarily associated with pernicious anaemia, polyneuropathy, and spinal-cord disease, but publications on its association with hallucinations are on the rise. Methods: I carried out a systematic literature search on these hallucinations in PubMed, PsycINFO, and Google Scholar, up until July 1, 2023. Results: The search yielded 50 case studies published between 1960 and 2023. The hallucinations described therein are predominantly visual and/or auditory in nature, with 20% being specified as complex, compound, or panoramic. They are often described in the context of vitamin B12-related neuropsychiatric conditions such as dementia, delirium, epilepsy, psychotic disorder, schizoaffective disorder, bipolar disorder, depressive disorder, catatonia, or obsessive-compulsive disorder. In the context of such disorders, they tend to appear first and also often appear to be the first to disappear with cobalamin treatment. Within an average of 2 months, full amelioration was thus obtained in 75% of the cases and partial amelioration in the remaining 25%. Remarkably, a quarter of the cases involved therapy-resistant hallucinations that fully resolved under cobalamin monotherapy, while other neuropsychiatric manifestations of vitamin B12 deficiency disappeared in 60% of the treated cases. Only 32% of the cases involved comorbid pernicious anaemia. This suggests that two separate or diverging pathways exist for perceptual and haematological symptoms of vitamin B12 deficiency. Conclusion: In the light of the high prevalence rate of vitamin B12 deficiency in the general population, the findings here presented should be interpreted with great caution. Nonetheless, they offer cues for further research and experimental application in clinical practice. This may be especially relevant in light of the recent increase in the popularity of vegetarianism and the recreational use of nitrous oxide (laughing gas), which are both risk factors for vitamin B12 deficiency. It has been known for a long time that low levels of vitamin B12 may cause pernicious anaemia and diseases of the nervous system. I here provide a systematic review on a less well-known association, namely with hallucinations. My search yielded 50 case studies published between 1960 and 2023. The hallucinations described therein are predominantly visual or auditory in nature. They tended to appear before any other vitamin-B12-related disorders, and they also appeared to be the first to go away when treatment was started with vitamin B12. Within an average of 2 months, the hallucinations thus treated vanished completely in 75% of the cases and partly in the remaining 25%. Remarkably, a quarter of the cases involved hallucinations that had shown to be resistant to treatment with antipsychotics and sometimes even to electroconvulsive therapy (ECT). Nonetheless, they fully resolved under treatment with vitamin B12 alone, while other symptoms disappeared in 60% of the treated cases. Another remarkable finding was that only 32% of the people described showed signs of pernicious anaemia. Since low levels of vitamin B12 are very common in the general population, the findings here presented should be interpreted with great caution. Nonetheless, they offer cues for further research and experimental treatment. This may be especially relevant in light of the recent increase in the popularity of vegetarianism and the recreational use of laughing gas, which may both cause levels of vitamin B12 to decline. [ABSTRACT FROM AUTHOR]

Atmospheric trace gas measurements can be used to independently assess national greenhouse gas inventories through inverse modeling. Atmospheric nitrous oxide (N2O) measurements made in the United Kingdom (UK) and Republic of Ireland are used to derive monthly N2O emissions for 2013–2022 using two different inverse methods. We find mean UK emissions of 90.5 ± 23.0 (1σ) and 111.7 ± 32.1 (1σ) Gg N2O yr−1 for 2013–2022, and corresponding trends of −0.68 ± 0.48 (1σ) Gg N2O yr−2 and −2.10 ± 0.72 (1σ) Gg N2O yr−2, respectively, for the two inverse methods. The UK National Atmospheric Emissions Inventory (NAEI) reported mean N2O emissions of 73.9 ± 1.7 (1σ) Gg N2O yr−1 across this period, which is 22%–51% smaller than the emissions derived from atmospheric data. We infer a pronounced seasonal cycle in N2O emissions, with a peak occurring in the spring and a second smaller peak in the late summer for certain years. The springtime peak has a long seasonal decline that contrasts with the sharp rise and fall of N2O emissions estimated from the bottom‐up UK Emissions Model (UKEM). Bayesian inference is used to minimize the seasonal cycle mismatch between the average top‐down (atmospheric data‐based) and bottom‐up (process model and inventory‐based) seasonal emissions at a sub‐sector level. Increasing agricultural manure management and decreasing synthetic fertilizer N2O emissions reduces some of the discrepancy between the average top‐down and bottom‐up seasonal cycles. Other possibilities could also explain these discrepancies, such as missing emissions from NH3 deposition, but these require further investigation. Plain Language Summary: Atmospheric nitrous oxide (N2O) is an important greenhouse gas and ozone depleting substance. Atmospheric N2O measurements made in the United Kingdom (UK) and Republic of Ireland were used to derive UK N2O emissions for 2013–2022 using two inverse methods. UK emissions derived using atmospheric N2O measurements were on average 22%–51% higher than emissions reported in the UK National Atmospheric Emissions Inventory. A pronounced seasonal cycle in N2O emissions is inferred from the atmospheric N2O observations which contrasts the seasonal N2O emissions estimated in the bottom‐up (process model and inventory‐based) UK Emissions Model (UKEM). We find increasing agricultural manure management N2O emissions and decreasing synthetic fertilizer N2O emissions reduces some of the discrepancy between the seasonal cycles. Key Points: Atmospheric N2O measurements from 2013 to 2022 are used to evaluate the UK's reported emissions using two inverse methodsEmissions derived from atmospheric data are on average 22%–51% higher than the UK's national emissions inventory values across 2013–2022Agreement between the average top‐down and bottom‐up seasonal emissions was improved by decreasing bottom‐up synthetic fertilizer emissions [ABSTRACT FROM AUTHOR]

This letter, published in the Journal of Anesthesia, Analgesia & Critical Care, discusses the environmental impact of anesthetic gases (AG) and the awareness of anesthesiologists regarding this issue. The study found that AG accounted for a significant portion of greenhouse gas emissions in healthcare systems. The researchers analyzed data from their university center and found that AG use did not decrease over the years, despite recommendations to consider alternative methods. They also conducted a survey among anesthesiologists and found that while most believed total intravenous anesthesia (TIVA) could substitute AG in a significant number of cases, many were unaware of the environmental impact of AG. The study suggests that there is room for improvement in reducing AG use and increasing awareness among anesthesiologists. [Extracted from the article]

This review consolidates the evidence supporting endogenous HNO generation through enzymatic and non‐enzymatic pathways, emphasizing advancements in real‐time HNO sensing within living systems. Azanone (nitroxyl, HNO) is the one‐electron‐reduced congener of nitric oxide (NO•) and shares various biological actions. HNO exhibits unique properties, including positive inotropic and lusitropic effects, along with resistance to scavenging by reactive oxygen species (ROS), particularly superoxide. Research on HNO has intensified over the last two decades, focusing on its reactivity and the prospect of endogenous formation due to its potential significance. The high reactivity of HNO arises from reactions with biologically relevant species such as oxygen, NO•, and thiols, as well as self‐dimerization. Detecting and quantifying HNO has posed challenges, initially relying on nitrous oxide (N2O) detection, a byproduct of dimerization. Recent advancements, including fluorescent probes and a specific electrochemical nanomolar‐level sensor, have facilitated direct detection, enhancing understanding of HNO reactivity and formation. [ABSTRACT FROM AUTHOR]

Background Aims Materials and Methods Results Conclusions Despite clinical and economic benefits, pain during outpatient hysteroscopy (OPH) remains a barrier to use. There is a lack of evidence to support routine use of one analgesic over another versus no analgesic.To study the efficacy and safety of methoxyflurane analgesia during OPH.A single‐centre, randomised, double‐blind, placebo‐controlled experiment was performed; 90 patients were randomly assigned (1:1). Participants allocated to the treatment group (cases) received 3 mL of methoxyflurane through an inhaler. The control group received a placebo. The primary outcome was a mean difference in pain, via a change in Visual Analog Scale (VAS) score from baseline at diagnostic hysteroscopy. Secondary outcomes were a mean difference in VAS score with any subsequent operative procedures; a mean difference in VAS score at 15 min post‐procedure; participant and clinician‐reported adverse effects and events; and participant‐reported procedure acceptability, adjuvant nitrous oxide (N2O2) use and a composite of ‘distress’.During diagnostic hysteroscopy, there was a mean difference of 11.5 mm/100 (95% confidence interval (CI) 0.08–22.95), P = 0.05, with the lower score in the cases, compared with controls. During subsequent operative procedures, there was a mean difference of 15 mm/100 (95% CI 2.71–28.22), P = 0.02, with the lower pain score in the cases, compared with controls. There was no significant difference in pain 15 min post‐procedure, participant‐ and clinician‐ reported adverse effects and events, procedure acceptability and the ‘distress’ composite.Methoxyflurane significantly reduced pain during OPH compared with placebo, for diagnostic as well as operative procedures. Furthermore, methoxyflurane was well tolerated, with no adverse events. [ABSTRACT FROM AUTHOR]

Introduction: The Avenir Santé Association implemented a comprehensive prevention program targeting the consumption of the emerging psychoactive substances ecstasy (MDMA), cannabidiol (CBD), and nitrous oxide (N2O). Methods: The program was evaluated through four actions: (i) training for association workers (n = 84) (ii) on-site student party interventions (n = 248), (iii) social network-based prevention (n = 186), and (iv) provision of prevention tools for party organizers (n = 148). Results: Results showed a significant increase in understanding of emerging substances among association workers, with a pre-training score of M = 15.76 (SD = 3.65) and a post-training score of M = 18.29 (SD = 2.50). Increased awareness and reflective attitudes toward substance use were observed among young people participating in field actions, with pre- and post-intervention scores for MDMA use intentions being M = 15.89 (SD = 4.60) and M = 19.17 (SD = 3.33), respectively. Similarly, awareness of CBD effects increased from M = 14.18 (SD = 4.14) to M = 17.60 (SD = 3.31). Exposure to Instagram posts on N2O led to more negative attitudes toward N2O among young people, with a significant change in scores from M = 8.16 (SD = 1.57) to M = 8.42 (SD = 1.26). However, exposure to a website providing information about emerging substances did not produce any significant effect. Discussion: In conclusion, this initiative underscores the usefulness of facilitator training, field interventions, and certain online information strategies for substance judgment and usage intentions. Future prevention programs can advantageously incorporate these actions. [ABSTRACT FROM AUTHOR]

Rice is the staple food in Sri Lanka, and over 15% of the national land is allocated for rice cultivation. Greenhouse gas (GHG) emissions from rice fields account for 10% of national GHG emissions. The country has committed to reducing its emissions by 14.5% between 2010 and 2030 and achieving net zero emissions by 2060. In 2021, the country banned agro-fertilizer imports and opted for organic fertilizers, leading to a notable decrease in production and posing challenges to food security. However, the impact of adopting compost fertilizers alone remains unexplored. This study evaluated the global warming impact of two organic fertilizer strategies: switching to compost fertilizer instead of urea and applying rice straw compost instead of retaining crop residue. We applied the Denitrification and Decomposition model (DNDC 95) to rice field management data from Sri Lanka's Mahaweli H agricultural region. Simulations suggest that both strategies would increase the global warming potential of rice fields, mainly owing to elevated N2O emissions. This outweighs the mitigation benefits of avoiding crop residue retention and adding organic carbon through compost. Overall, our results point to the potential risk of shifting exclusively to compost-based fertilizers. [ABSTRACT FROM AUTHOR]

Nitrogen oxides, including nitrous oxide (N2O), are undoubtedly classified as greenhouse gases. In this research, we conducted a theoretical investigation into the N2O capturing reactions using frustrated Lewis pair (FLP)-assisted molecules based on the intramolecular dimethylxanthene backbone G13/P (G13 = B, Al, Ga, In, and Tl) and B/G15 (G15 = N, P, As, Sb, and Bi). Density functional theory (DFT) along with frontier molecular orbital (FMO) theory, activation strain model (ASM), and energy decomposition analysis–the natural orbitals for the chemical valence (EDA–NOCV) were employed to analyze the molecular reaction barriers and chemical reactivity. From the DFT calculations, it is evident that only B/P-Rea, among the FLP-type molecules utilizing G13/P and B/G15 as Lewis base/Lewis acid sites, exhibits the ability to capture N2O in a reversible reaction. The EDA examinations suggest that the bonding nature between the G13/G15-FLP and N2O in the G13/G15-TS structure can be elucidated by the donor–acceptor interaction (singlet–singlet bonding) model, instead of the electron-sharing interaction (triplet–triplet bonding) model. FMO and NOCV analyses reveal that the reaction between N2O and the G13/G15-based FLP exhibits two distinct bonding properties: one is the forward bonding, the lone pair of G15 → the p–π* orbital of the N-terminus of N2O, which is a significantly strong FLP-to-N2O interaction. The other is the back-bonding, the empty orbital of G13 ← the filled p–π orbital of the O atom of N2O, which is a relatively weak N2O-to-FLP interaction. In basic terms, Lewis base interacting with N2O is more pivotal than the interaction of Lewis acid with N2O. The ASM analytical findings indicate that the deformation energy of the small N2O molecule significantly influences the reaction barrier of the N2O capture reaction by the intramolecular dimethylxanthene-linked G13/G15-FLPs. The theoretical evidence for N2O capture by intramolecular dimethylxanthene-linked G13/G15-based FLPs shows that the relationships between geometrical structures and energetic values are in accordance with the Hammond postulate. [ABSTRACT FROM AUTHOR]

Fertilizer application is the basis for ensuring high yield, high quality and high efficiency of farmland. In order to meet the demand for food with the increasing of population, the application of nitrogen fertilizer will be further increased, which will lead to problems such as N2O emission and nitrogen loss from farmland, it will easily deteriorate the soil and water environment of farmland, and will not conducive to the sustainable development of modern agriculture. However, optimizing fertilizer management is an important way to solve this problem. While, due to the differences in the study conditions (geographical location, environmental conditions, experimental design, etc.), leading to the results obtained in the literatures about the N2O emission with different nitrogen fertilizer application strategies have significant differences, which requiring further comprehensive quantitative analysis. Therefore, we analyzed the effects of nitrogen fertilizer application strategies (different fertilizer types and fertilizer application rates) on N2O emissions from the fields (rice, wheat and maize) based on the Meta-analysis using 67 published studies (including 1289 comparisons). For the three crops, inorganic fertilizer application significantly increased on-farm N2O emissions by 19.7–101.05% for all three; and organic fertilizer increased N2O emissions by 28.16% and 69.44% in wheat and maize fields, respectively, but the application of organic fertilizer in rice field significantly reduced N2O emissions by 58.1%. The results showed that overall, the application of inorganic fertilizers resulted in higher N2O emissions from farmland compared to the application of organic fertilizers. In addition, in this study, the average annual temperature, annual precipitation, soil type, pH, soil total nitrogen content, soil organic carbon content, and soil bulk weight were used as the main influencing factors of N2O emission under nitrogen fertilizer strategies, and the results of the study can provide a reference for the development of integrated management measures to control greenhouse gas emissions from agricultural soils. [ABSTRACT FROM AUTHOR]

The abuse of nitrous oxide (N2O) poses a substantial public health challenge. In many countries, including China, regulations governing the utilization and accessibility to N2O remain ambiguous, particularly within the food industry. Here, we report a case of a 21-year-old female who presented with symptoms of subacute combined degeneration (SCD) of the spinal cord due to N2O abuse. The patient exhibited bilateral lower limb numbness and weakness, low serum vitamin B12 levels with elevated homocysteine levels, and lumbar spine magnetic resonance imaging (MRI) revealed abnormal signals of the spinal cord. Following cessation of N2O and comprehensive therapy including methylcobalamin and nerve growth factor, the symptoms significantly improved. A follow-up examination 3 months later showed good progress in gait stability. At a 5-year follow-up, the patient’s previous clinical symptoms had completely disappeared, and her quality of life had returned to normal. This case underscores the urgency of raising awareness and prevention of N2O abuse, emphasizing the importance of timely diagnosis and comprehensive treatment for patient recovery. Clear formulation and enforcement of relevant regulatory measures are equally crucial in reducing instances of abuse. [ABSTRACT FROM AUTHOR]

In this study, we provide an update of the methodology and data used by Deng et al. (2022) to compare the national greenhouse gas inventories (NGHGIs) and atmospheric inversion model ensembles contributed by international research teams coordinated by the Global Carbon Project. The comparison framework uses transparent processing of the net ecosystem exchange fluxes of carbon dioxide (CO2) from inversions to provide estimates of terrestrial carbon stock changes over managed land that can be used to evaluate NGHGIs. For methane (CH4), and nitrous oxide (N2O), we separate anthropogenic emissions from natural sources based directly on the inversion results, to make them compatible with NGHGIs. Our global harmonized NGHGIs database was updated with inventory data until February 2023 by compiling data from periodical UNFCCC inventories by Annex I countries and sporadic and less detailed emissions reports by non-Annex I countries given by National Communications and Biennial Update Reports. For the inversion data, we used an ensemble of 22 global inversions produced for the most recent assessments of the global budgets of CO2, CH4 and N2O coordinated by the Global Carbon Project with ancillary data. The CO2 inversion ensemble in this study goes through 2021, building on our previous report from 1990 to 2019, and includes three new satellite inversions compared to the previous study, and an improved managed land mask. As a result, although significant differences exist between the CO2 inversion estimates, both satellite and in-situ inversions over managed lands indicate that Russia and Canada had a larger land carbon sink in recent years than reported in their NGHGIs, while the NGHGIs reported a significant upward trend of carbon sink in Russia but a downward trend in Canada. For CH4 and N2O, the results of the new inversion ensembles are extended to 2020. Rapid increases in anthropogenic CH4 emissions were observed in developing countries, with varying levels of agreement between NGHGIs and inversion results, while developed countries showed a slow declining or stable trend in emissions. Much denser sampling and higher atmospheric CO2 and CH4 concentrations by different satellites, are expected in the coming years. The methodology proposed here to compare inversion results with NGHGIs can be applied regularly for monitoring the effectiveness of mitigation policy and progress by countries to meet the objective of their pledges. The dataset constructed for this study is publicly available at https://doi.org/10.5281/zenodo.10841716 (Deng et al., 2024). [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the environmental impact of travel and anesthetic gas emissions associated with treating early childhood caries at a single institution. Methods: Outpatient preventive, treatment, and modeled general anesthesia (GA) cases in children 71 months old and younger were included in this retrospective chart review. The main outcomes were kilograms of carbon dioxide equivalents (kgCO2e) for travel- and anesthetic gas-related emissions. Descriptive statistics and non-parametric tests were used. Results: Most subjects had a caries treatment visit (N equals 3,630 out of 5,767), and nine percent of treatment visits (N equals 353 out of 3,630) received nitrous oxide (N2O), which added 29.4 kgCO2e to the visit emissions. Children without caries treatment had lower travel-related emissions (median equals 7.5 kgCO2e; interquartile range [IQR] equals 7.6) than children with caries treatment (median without N2O equals 8.7 kgCO2e; IQR equals 18.2; median with N2O equals 8.4 kgCO2e; IQR equals 10.3). Modeled GA travel emissions were estimated at 16.4 kgCO2e (IQR equals 21.9) with between 3.8-12.9 kgCO2e in anesthetic gas emissions. Total emissions were greatest for N2O treatment visits (median equals 43.3 kgCO2e; IQR equals 22.8). Conclusions: Travel-related emissions were greatest for children requiring caries treatment. Minimizing patient travel may reduce environmental impact. Nitrous oxide contributes a significant amount to a dental visit's environmental impact. Community-focused models of care and applying systematic and practical case selection to reduce excess N2O emissions could reduce dental care-related carbon emissions. [ABSTRACT FROM AUTHOR]

Why you should read this article: • To learn about the history of nitrous oxide (N2O) as a recreational drug and as an analgesic and anaesthetic • To enhance your understanding of the adverse effects and risks of recreational N2O use • To refresh your knowledge of the pathophysiology and management of cold burn injuries. Nitrous oxide (N2O) has become one of the most popular recreational drugs in Europe. While N2O is often used in medical settings as an analgesic and anaesthetic agent, its recreational use was documented many years before its introduction into clinical practice. The desired effects from inhaling N2O for recreational purposes include rapid feelings of relaxation, calmness and euphoria, which can be accompanied by giddiness and laughter. There are various adverse effects associated with N2O use, including headache, nausea, vomiting, drowsiness and the development of permanent neurological damage. Furthermore, its use is associated with cold burns and road accidents. This article details the case of a patient who sustained an N2O tank burn to his forearm from recreational use. It also discusses the prevalence, legal status and adverse effects of N2O use as well as the pathophysiology and management of cold burn injuries. [ABSTRACT FROM AUTHOR]

Nitrification inhibitors, such as nitrapyrin (NI), are increasingly co‐applied with nitrogen (N) fertilizers as part of sustainable agricultural practice. Several studies in temperate regions have documented the effectiveness of NI in retaining soil ammonium (NH4+), minimizing N loss and increasing crop yields. However, less is known about the effects of NI in Mediterranean regions, where agricultural production is challenging and requires intensive irrigation and fertilization. We investigated the short‐term impact of the nitrification inhibitor nitrapyrin (2‐chloro‐6‐(trichloromethyl)pyridine) in a two‐factor mesocosm experiment, using a typical Mediterranean soil, where NI was co‐applied with a selection of urea‐based fertilizers: urea (U), U with urease inhibitors (U + UI), methylene urea (MU) and zeolite‐coated urea (ZU). NI co‐applied with urea fertilizers resulted in higher availability of soil NH4+ and a concurrent increase in NH3 volatilization. Net cumulative soil NH4+ availability was 1.5–3.3 fold greater when NI was applied. Concurrently, net cumulative nitrate (NO3−) and nitrite (NO2−) availability was reduced by 10%–60%; this was found for all the tested fertilizer types except MU fertilizer, where the net cumulative soil NO3− and NO2− doubled. Nitrous oxide (N2O) emissions from urea fertilization were reduced by 40% with UI, 50% with NI and 66% with NI + UI. Interestingly, after 28 d, the composition of soil microbial communities was distinctly different, due to NI application. Specifically, NI application dramatically reduced the abundance of ammonia‐oxidizing and denitrifying bacterial functional groups. NI was effective in reducing N2O emissions in this calcareous soil; however, NH3 emissions were remarkably enhanced. These findings have important implications for the large‐scale adoption of inhibitor technologies in Mediterranean agroecosystems and for the reduction of greenhouse gas emissions. [ABSTRACT FROM AUTHOR]