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The sources and sinks of nitrous oxide, as control emissions to the atmosphere, are generally poorly constrained for most environmental systems. Initial depth-resolved analysis of nitrous oxide flux from observation wells and the proximal surface within a nitrate contaminated aquifer system revealed high subsurface production but little escape from the surface. To better understand the environmental controls of production and emission at this site, we used a combination of isotopic, geochemical, and molecular analyses to show that chemodenitrification and bacterial denitrification are major sources of nitrous oxide in this subsurface, where low DO, low pH, and high nitrate are correlated with significant nitrous oxide production. Depth-resolved metagenomes showed that consumption of nitrous oxide near the surface was correlated with an enrichment of Clade II nitrous oxide reducers, consistent with a growing appreciation of their importance in controlling release of nitrous oxide to the atmosphere. Our work also provides evidence for the reduction of nitrous oxide at a pH of 4, well below the generally accepted limit of pH 5.

Global potent greenhouse gas nitrous oxide (N2O) emissions from soil are accelerating, with increases in the proportion of reactive nitrogen emitted as N2O, i.e., N2O emission factor (EF). Yet, the primary controls and underlying mechanisms of EFs remain unresolved. Based on two independent but complementary global syntheses, and three field studies determining effects of acidity on N2O EFs and soil denitrifying microorganisms, we show that soil pH predominantly controls N2O EFs and emissions by affecting the denitrifier community composition. Analysis of 5438 paired data points of N2O emission fluxes revealed a hump-shaped relationship between soil pH and EFs, with the highest EFs occurring in moderately acidic soils that favored N2O-producing over N2O-consuming microorganisms, and induced high N2O emissions. Our results illustrate that soil pH has a unimodal relationship with soil denitrifiers and EFs, and the net N2O emission depends on both the N2O/(N2O + N2) ratio and overall denitrification rate. These findings can inform strategies to predict and mitigate soil N2O emissions under future nitrogen input scenarios.

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-oxidizing archaea (AOA) are key players in the nitrogen cycle and among the most abundant microorganisms in the ocean, thriving even in oxygen-depleted ecosystems. AOA produce the greenhouse gas nitrous oxide (N2O) as a byproduct of ammonia oxidation. Additionally, the recent discovery of a nitric oxide dismutation pathway in the AOA isolate Nitrosopumilus maritimus points toward other N2O production and consumption pathways in AOA. AOA that perform NO dismutation when exposed to oxygen depletion, produce oxygen and dinitrogen as final products. Based on the transient accumulation of N2O coupled with oxygen accumulation, N2O has been proposed as an intermediate in this novel archaeal pathway. In this study, we spiked N2O to oxygen-depleted incubations with pure cultures of two marine AOA isolates that were performing NO dismutation. By using combinations of N compounds with different isotopic signatures (15NO2 - pool +44N2O spike and 14NO2 - pool +46N2O spike), we evaluated the N2O spike effects on the production of oxygen and the isotopic signature of N2 and N2O. The experiments confirmed that N2O is an intermediate in NO dismutation by AOA, distinguishing it from similar pathways in other microbial clades. Furthermore, we showed that AOA rapidly reduce high concentrations of spiked N2O to N2. These findings advance our understanding of microbial N2O production and consumption in oxygen-depleted settings and highlight AOA as potentially important key players in N2O turnover. [ABSTRACT FROM AUTHOR]

Background: Silage emits climate- and environment-relevant gases during fermentation and feed-out periods. This trial aimed to determine the unknown carbon dioxide (CO2), methane, nitrous oxide, ethanol, and ethyl acetate emissions of constant maize silage material over both periods. The results will be published in two consecutive articles (Part A: anaerobic fermentation period, Part B: aerobic storage period). Methods: The untreated control (CON) was compared with the chemical additive treatment (CHE; 0.5 g sodium benzoate and 0.3 g potassium sorbate per kg fresh matter) and the biological additive treatment (BIO; 108 colony-forming units (CFU) Lentilactobacillus buchneri and 107 CFU Lactiplantibacillus plantarum per kg fresh matter). Barrel silos (n = 4) were connected to gas bags to quantify gas formation during anaerobic fermentation (30 or 135 ensiling days). Glass jar silos (n = 12) were used for laboratory silage analysis. Results: CHE produced significantly (p < 0.05) less gas (6.7 ± 0.3 L per kg dry matter ensiled material (kgDM) until ensiling day 14.0 ± 0.0) and ethanol (8.6 ± 1.5 mg kgDM–1) than CON did (8.5 ± 0.2 L kgDM–1 until ensiling day 19.5 ± 6.4; 12.2 ± 1.5 (mg ethanol) kgDM–1). BIO indicates prolonged gas formation (9.1 ± 0.9 L kgDM–1 until ensiling day 61.3 ± 51.9; 12.0 ± 2.1 mg kgDM–1). CO2 is the main component of the gas formed. All treatments formed methane and nitrous oxide in small quantities. CON emitted significantly more CO2eq emissions than BIO and less than CHE (p < 0.05). Additives had no effect on ethyl acetate gas emissions. For BIO, ethanol concentrations in the material (rS = 0.609, p < 0.05) and gas quantities (rS = 0.691, p < 0.05) correlate with ethyl acetate gas quantities. All the treatments exhibited decreasing gas and CO2 quantities, and the dry matter mass increased between ensiling days 14 and 30 (− 0.810 ≤ rS ≤ 0.442; p < 0.05 to p = 0.20). Conclusion: Silage generates climate- and environmental-relevant gases during fermentation and silage additives affect this pattern. Gas formation exceeds the fixation potential, and the carbon footprint of silage fermentation is negative. [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: 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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

The decline in global plant diversity has raised concerns about its implications for carbon fixation and global greenhouse gas emissions (GGE), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Therefore, we conducted a comprehensive meta‐analysis of 2103 paired observations, examining GGE, soil organic carbon (SOC) and plant carbon in plant mixtures and monocultures. Our findings indicate that plant mixtures decrease soil N2O emissions by 21.4% compared to monocultures. No significant differences occurred between mixtures and monocultures for soil CO2 emissions, CH4 emissions or CH4 uptake. Plant mixtures exhibit higher SOC and plant carbon storage than monocultures. After 10 years of vegetation development, a 40% reduction in species richness decreases SOC content and plant carbon storage by 12.3% and 58.7% respectively. These findings offer insights into the intricate connections between plant diversity, soil and plant carbon storage and GGE—a critical but previously unexamined aspect of biodiversity–ecosystem functioning. [ABSTRACT FROM AUTHOR]

Background: The factors underlying the topography of nitrous oxide (N2O)‐induced neurological complications are unknown. Methods: We included all consecutive patients admitted to the university hospital of Marseille for N2O‐induced neurological complications in a prospective observational study. Patients underwent neurological examination, spinal cord magnetic resonance imaging, and nerve conduction studies within the first 4 weeks after admission. Results: In total, 61 patients were included: 45% with myeloneuropathy, 34% with isolated myelopathy, and 21% with isolated neuropathy. On multivariable analysis, the odds of myelopathy were associated with the amount of weekly N2O consumption (~600 g cylinder per week, odds ratio [OR] = 1.11, 95% confidence interval [CI] = 1.001–1.24). The extent of the myelopathy (number of vertebral segments) was correlated with the number of ~600‐g cylinders consumed weekly (ρ = 0.40, p < 0.005). The odds of neuropathy were associated with the duration of consumption (per month; OR = 1.29, 95% CI = 1.05–1.58). Mean lower‐limb motor nerve amplitude was correlated with the duration of consumption (in months; ρ = −0.34, p < 0.05). Conclusions: The odds of myelopathy increased with the amount of N2O consumption, and the odds of neuropathy increased with the duration of N2O exposure, which suggests distinct pathophysiological mechanisms underlying these two neurological complications. [ABSTRACT FROM AUTHOR]

Climate change has been intensifying soil drying and rewetting cycles, which can alter the soil microbiome structure and activity. Here we hypothesized that a soil drying-rewetting cycle enhances biodegradation and, hence, decreases the effectiveness of nitrification inhibitors (NIs). The effectiveness of DMPP (3,4-Dimethylpyrazole phosphate) and MP + TZ (3-Methylpyrazol and Triazol) was evaluated in 60-day incubation studies under a drying and rewetting cycle relative to constant low and high soil moisture conditions (40% and 80% water-holding capacity, WHC, respectively) in two different textured soils. The measurements included (i) daily and cumulative N2O-N emissions, (ii) soil NH4+-N and NO3−-N concentrations, and (iii) the composition of bacterial soil communities. Application of DMPP and MP + TZ reduced the overall N2O-N emissions under drying-rewetting (-45%), as well as under 40% WHC (-39%) and 80% WHC (-25%). DMPP retarded nitrification and decreased N2O-N release from the sandy and silt loam soils, while MP + TZ mitigated N2O-N production only from the silt loam soil. Unexpectedly, between days 30 and 60, N2O-N emissions from NI-treated soils increased by up to fivefold relative to the No-NI treatment in the silt loam soil at 80% WHC. Likewise, the relative abundance of the studied nitrifying bacteria indicated that the NIs had only short-term effectiveness in the silt loam soil. These results suggested that DMPP and MP + TZ might trigger high N2O-N release from fine-textured soil with constant high moisture after this short-term inhibitory effect. In conclusion, DMPP and MP + TZ effectively reduce N2O-N emissions under soil drying and rewetting. [ABSTRACT FROM AUTHOR]

The substitution of chemical fertilizers with organic manure plays a critical role in sustainable crop production. Nevertheless, organic amendments promote the global warming potential (GWP) in rice paddies due to increased methane (CH4) emissions. Increasing evidence shows that lime application can reduce CH4 emissions from acidic paddy soils; however, it is still not clear whether liming can reduce the GWP in rice fields under organic manure substitution. A two-year field experiment was conducted to investigate the impacts of pig manure substitution and lime application on grain yield, CH4 and nitrous oxide (N2O) emissions in a subtropical double-cropped rice field in China. The experiment consisted of three treatments: CF (100% chemical nitrogen fertilizer), 1/2N + M (50% of the applied nitrogen substituted by pig manure, M represents manure), and 1/2N + M + L (lime amendment with 50% of the applied nitrogen substituted with pig manure, L represents lime). On average, 1/2N + M reduced rice yield by 5.65% compared to CF, while the lime application had no effect on rice yield. Mean cumulative CH4 emissions were 218.8% higher in 1/2N + M than in CF, whereas 1/2N + M + L reduced CH4 emissions by 36.6% compared to 1/2N + M. Neither pig manure substitution nor lime application affected N2O emissions. Consequently, 1/2N + M increased the GWP and greenhouse gas intensity (GHGI) by 214.6% and 228.3%, respectively, compared to CF. In contrast, 1/2N + M + L reduced the GWP and GHGI by 36.4% and 36.5% compared to 1/2N + M. Lime application can mitigate CH4 emissions and GWP induced by pig manure amendment in double-cropped rice fields. [ABSTRACT FROM AUTHOR]

In the current era, it has become essential to move toward highly efficient and low-emission engines as the norms for automobile emissions are very stringent and closely monitored; moreover, it also tends to be more strictly regulated in the future. The aim of this experimental work is to optimize engine efficiency as well as reduce emissions to the maximum using oxygen-enriched air. An onboard oxygen generator can provide oxygen-enriched air instead of an oxygen cylinder, as the latter one is prone to cause safety issues. In this experimental study, oxygen is obtained through generator and is sent to the engine's intake manifold, where the atmospheric air merges with it. The parameters of combustion, performance, and emission of this oxygen-enriched air were examined in a constant-speed compression ignition engine. The result shows that the engine's brake thermal efficiency increased by 5.4% at 25% of brake power as compared to the thermal efficiency attained in atmospheric air combustion. Similarly, brake-specific fuel consumption also decreased in the oxygen-enriched combustion process. The emissions of hydrocarbon and carbon monoxide also decreased to 18.8% and 33.3%, respectively, for 25% of the brake power; notably, the smoke emissions reduced drastically to 32% at the same brake power. The oxides of nitrogen emission, however, increased with the air's oxygen content. [ABSTRACT FROM AUTHOR]

Soils are the largest source of atmospheric nitrous oxide (N2O), a powerful greenhouse gas. Dry soils rarely harbor anoxic conditions to favor denitrification, the predominant N2O-producing process, yet, among the largest N2O emissions have been measured after wetting summer-dry desert soils, raising the question: Can denitrifiers endure extreme drought and produce N2O immediately after rainfall? Using isotopic and molecular approaches in a California desert, we found that denitrifiers produced N2O within 15 minutes of wetting dry soils (site preference = 12.8 ± 3.92 per mil, δ15Nbulk = 18.6 ± 11.1 per mil). Consistent with this finding, we detected nitrate-reducing transcripts in dry soils and found that inhibiting microbial activity decreased N2O emissions by 59%. Our results suggest that despite extreme environmental conditions-months without precipitation, soil temperatures of ≥40°C, and gravimetric soil water content of

Introduction: Weakness is a common symptom that within itself does not indicate a specific diagnosis. Recreational inhalant use such as nitrous oxide (NO) may not often be disclosed. Additionally, professional or occupational history, such as being a dentist or dental assistant, should be determined because of higher reported rates of NO misuse.1 Nitrous oxide can cause vitamin B12 deficiency and resulting neuropathy. Nitrous oxide toxicity can have a wide variation of presentations with or without laboratory abnormalities or remarkable imaging findings, which can further complicate a diagnosis of weakness secondary to NO use. Case Report: A 33-year-old female presented to the emergency department with progressive bilateral leg numbness and objective weakness after repeated recreational NO use. After an extensive workup, she was found to have vitamin B12 deficiency and an electromyography study consistent with myeloneuropathy, despite normal imaging. She was prescribed high-dose vitamin B12 therapy and stopped using NO. One year after diagnosis, our patient maintained NO sobriety and had near-complete resolution of prior neurologic deficits. Conclusion: The use of recreational inhalant and the patient’s occupation should be considered when a patient presents with weakness. Obtaining vitamin B12 and methylmalonic acid levels should be considered for diagnosis. However, NO-induced neuropathy can be seen in patients with normal vitamin B12 and methylmalonic levels and patients do not always have abnormal imaging findings. The healthcare team should consider the varied presentations and findings of substance-induced conditions such as NO toxicity.

Agriculture contributes nearly a quarter of global greenhouse gas (GHG) emissions, which is motivating interest in adopting certain farming practices that have the potential to reduce GHG emissions or sequester carbon in soil. The related GHG emission (including N2O and CH4) and changes in soil carbon stock are defined here as “agricultural carbon outcomes”. Accurate quantification of agricultural carbon outcomes is the basis for achieving emission reductions for agriculture, but existing approaches for measuring carbon outcomes (including direct measurements, emission factors, and process-based modeling) fall short of achieving the required accuracy and scalability necessary to support credible, verifiable, and cost-effective measurement and improvement of these carbon outcomes. Here we propose a foundational and scalable framework to quantify field-level carbon outcomes for farmland, which is based on the holistic carbon balance of the agroecosystem: Agroecosystem Carbon Outcomes = Environment (E) × Management (M) × Crop (C). Following a comprehensive review of the scientific challenges associated with existing approaches, as well as their tradeoffs between cost and accuracy, we propose that the most viable path for the quantification of field-level carbon outcomes in agricultural land is through an effective integration of various approaches (e.g. diverse observations, sensor/in-situ data, and modeling), defined as the “System-of-Systems” solution. Such a “System-of-Systems” solution should simultaneously comprise the following components: (1) scalable collection of ground truth data and cross-scale sensing of environment variables (E), management practices (M), and crop conditions (C) at the local field level; (2) advanced modeling with necessary processes to support the quantification of carbon outcomes; (3) systematic Model-Data Fusion (MDF), i.e. robust and efficient methods to integrate sensing data and models at each local farmland level; (4) high computation efficiency and artificial intelligence (AI) to scale to millions of individual fields with low cost; and (5) robust and multi-tier validation systems and infrastructures to ensure solution fidelity and true scalability, i.e. the ability of a solution to perform robustly with accepted accuracy on all targeted fields. In this regard, we provide here the detailed scientific rationale, current progress, and future research and development (R&D) priorities to achieve different components of the “System-of-Systems” solution, thus accomplishing the Environment×Management×Crop framework to quantify field-level agricultural carbon outcomes.