Read by QxMD icon Read

Nitrous oxide

Carlos Domingo-Félez, Maria Calderó-Pascual, Gürkan Sin, Benedek G Plósz, Barth F Smets
The NDHA model comprehensively describes nitrous oxide (N2O) producing pathways by both autotrophic ammonium oxidizing and heterotrophic bacteria. The model was calibrated via a set of targeted extant respirometric assays using enriched nitrifying biomass from a lab-scale reactor. Biomass response to ammonium, hydroxylamine, nitrite and N2O additions under aerobic and anaerobic conditions were tracked with continuous measurement of dissolved oxygen (DO) and N2O. The sequential addition of substrate pulses allowed the isolation of oxygen-consuming processes...
September 7, 2017: Water Research
Keith Fluegge, Kyle Fluegge
It has previously been demonstrated that emissions of the agricultural pollutant, nitrous oxide (N2O), may be a confounder to the relationship between herbicide use and psychiatric impairments, including ADHD. This report attempts to extend this hypothesis by testing whether annual use of anthropogenic nitrogen-based fertilizers in U.S. agriculture (thought to be the most reliable indicator of environmental N2O emissions) is associated with per capita ethanol consumption patterns, a behavior often comorbid with ADHD...
September 2017: Medical Hypotheses
Zhili Li, Zhen Wang, Fan Yang, Wei Jin, Wei Ren
We demonstrate mid-infrared photothermal interferometry (PTI) in a hollow-core fiber (HCF) for trace gas detection. Compared with free-space PTI, the optical intensity could be increased by orders of magnitude by confining the pump and probe lights in the hollow core. We coupled the pump light at 4.46 μm from a quantum cascade laser and the 1555.14 nm probe light into the HCF with a bore size of 200 μm. The HCF was filled with nitrous oxide (N2O) which has strong absorption at the pump wavelength. The probe light detects the N2O absorption-induced phase change in the HCF via a fiber-optic Mach-Zehnder interferometer...
September 15, 2017: Optics Letters
P V Samir, Srinivas Namineni, P Sarada
PURPOSE: To assess the efficacy of nitrous oxide (N2O)-oxygen (O2) inhalation sedation by rapid induction technique using preadjusted mix of 30% N2O and 70% O2 in children. MATERIALS AND METHODS: Sixty children with a treatment plan which included pulp therapy were recruited for the study. Children categorized 3 and 4 of Frankl behavior rating scale and American Society of Anesthesiologists health status I and II were included for the study. Children were distributed into study group (Group-I) and control group (Group-II) by fishbowl randomization...
October 2017: Journal of the Indian Society of Pedodontics and Preventive Dentistry
María J Torres, Emilio Bueno, Andrea Jiménez-Leiva, Juan J Cabrera, Eulogio J Bedmar, Socorro Mesa, María J Delgado
The powerful greenhouse gas, nitrous oxide (N2O) has a strong potential to drive climate change. Soils are the major source of N2O and microbial nitrification and denitrification the main processes involved. The soybean endosymbiont Bradyrhizobium diazoefficiens is considered a model to study rhizobial denitrification, which depends on the napEDABC, nirK, norCBQD, and nosRZDYFLX genes. In this bacterium, the role of the regulatory cascade FixLJ-FixK2-NnrR in the expression of napEDABC, nirK, and norCBQD genes involved in N2O synthesis has been previously unraveled...
2017: Frontiers in Microbiology
Seung Tak Jeong, Gil Won Kim, Hyun Young Hwang, Pil Joo Kim, Sang Yoon Kim
Livestock manure application can stimulate greenhouse gas (GHG) emissions, especially methane (CH4) in rice paddy. The stabilized organic matter (OM) is recommended to suppress CH4 emission without counting the additional GHG emission during the composting process. To evaluate the effect of compost utilization on the net global warming potential (GWP) of a rice cropping system, the fluxes of GHGs from composting to land application were calculated by a life cycle assessment (LCA) method. The model framework was composed of GHG fluxes from industrial activities and biogenic GHG fluxes from the composting and rice cultivation processes...
September 11, 2017: Science of the Total Environment
Beibei Hu, Dongqi Wang, Jun Zhou, Weiqing Meng, Chongwei Li, Zongbin Sun, Xin Guo, Zhongliang Wang
Carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) concentration, saturation and fluxes in rivers (Beitang drainage river, Dagu drainage rive, Duliujianhe river, Yongdingxinhe river and Nanyunhe river) of Tianjin city (Haihe watershed) were investigated during July and October in 2014, and January and April in 2015 by static headspace gas chromatography method and the two-layer model of diffusive gas exchange. The influence of environmental variables on greenhouse gases (GHGs) concentration under the disturbance of anthropogenic activities was discussed by Spearman correlative analysis and multiple stepwise regression analysis...
September 9, 2017: Science of the Total Environment
I Santín, M Barbu, C Pedret, R Vilanova
The present paper focused on reducing greenhouse gases emissions in wastewater treatment plants operation by application of suitable control strategies. Specifically, the objective is to reduce nitrous oxide emissions during the nitrification process. Incomplete nitrification in the aerobic tanks can lead to an accumulation of nitrite that triggers the nitrous oxide emissions. In order to avoid the peaks of nitrous oxide emissions, this paper proposes a cascade control configuration by manipulating the dissolved oxygen set-points in the aerobic tanks...
August 28, 2017: Water Research
Bin Ma, Lan Yang, Qilin Wang, Zhiguo Yuan, Yayi Wang, Yongzhen Peng
Inactivation and adaptation of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) to free nitrous acid (FNA) was investigated. Batch test results showed that AOB and NOB were inactivated when treated with FNA. After an 85-day operating period, AOB in a continuous pre-denitrification reactor did not adapt to the FNA that was applied to treat some of the return activated sludge. In contrast, NOB did adapt to FNA. NOB activity in the seed sludge was only 11% of the original activity after FNA batch treatment, at 0...
August 15, 2017: Bioresource Technology
Ranjana Venkatachalapathy, Anusha Cherian, Sakthirajan Panneerselvam
INTRODUCTION: Low flow anaesthesia utilising Oxygen (O2) and Nitrous Oxide (N2O) mixture carries a risk of hypoxia, but avoiding N2O results in increased analgesic and volatile anaesthetic agent requirement. AIM: This study attempted to find the lowest Fraction of inspired Oxygen (FiO2) levels achieved with a mixture of 300 mL/min each of O2 and medical air over two hours and to compare the overall analgesic requirement and cost while using similar flows of N2O and O2, respectively...
July 2017: Journal of Clinical and Diagnostic Research: JCDR
Wanlin Lyu, Lei Huang, Guangquan Xiao, Yucheng Chen
A set of constructed wetlands under two different carbon sources, namely, glucose (CW) and sodium acetate (YW), was established at a laboratory scale with influent COD/N ratios of 20:1, 10:1, 7:1, 4:1, and 0 to analyze the influence of carbon supply on nitrous oxide emissions. Results showed that the glucose systems generated higher N2O emissions than those of the sodium acetate systems. The higher amount of N2O-releasing fluxes in the CWs than in the YWs was consistent with the higher NO2(-)-N accumulation in the former than in the latter...
August 13, 2017: Bioresource Technology
Linda Hink, Pawel Lycus, Cécile Gubry-Rangin, Åsa Frostegård, Graeme W Nicol, James I Prosser, Lars R Bakken
Ammonia oxidising bacteria (AOB) are thought to emit more nitrous oxide (N2 O) than ammonia oxidising archaea (AOA), due to their higher N2 O yield under oxic conditions and denitrification in response to oxygen (O2 ) limitation. We determined the kinetics of growth and turnover of nitric oxide (NO) and N2 O at low cell densities of Nitrosomonas europaea (AOB) and Nitrosopumilus maritimus (AOA) during gradual depletion of TAN (NH3  + NH4(+) ) and O2 . Half-saturation constants for O2 and TAN were similar to those determined by others, except for the half-saturation constant for ammonium in N...
September 11, 2017: Environmental Microbiology
Mansoor Masjedi, Alireza Ghanbari, Hossein Haddad Bakhodaei, Tahere Jowkar, Vahhab Hosseni, Mahnaz Rakhshan
BACKGROUND: Despite recent innovations in cataract surgery, pupillary diameter is one of the most important affecting factors in outcome of this surgery. As cataract surgery is performed ideally when the pupil is sufficiently dilated, anesthesia may contribute significantly in success or failure of this operation. This study was performed to evaluate the effect of nitrous oxide on pupillary diameter in cataract surgery under general anesthesia. METHODS: Forty patients with cataract, scheduled for operation under general anesthesia, were randomly allocated into two groups...
September 7, 2017: Journal of the Chinese Medical Association: JCMA
Zhisheng Yao, Guangxuan Yan, Xunhua Zheng, Rui Wang, Chunyan Liu, Klaus Butterbach-Bahl
High nitrogen (N) inputs in Chinese vegetable and cereal productions played key roles in increasing crop yields. However, emissions of the potent greenhouse gas nitrous oxide (N2O) and atmospheric pollutant nitric oxide (NO) increased too. For lowering the environmental costs of crop production, it is essential to optimize N strategies to maintain high crop productivity, while reducing the associated N losses. We performed a 2 year-round field study regarding the effect of different combinations of poultry manure and chemical N fertilizers on crop yields, N use efficiency (NUE) and N2O and NO fluxes from a Welsh onion-winter wheat system in the North China Plain...
September 6, 2017: Environmental Pollution
Keith Fluegge Ba
OBJECTIVE: Sayehmiri et al. recently conducted a meta-analysis to explore the relationship between zinc and copper metabolism and autism spectrum disorders (ASD). Recent reports have elucidated a full behavioral profile of mice exposed to prenatal zinc deficiency and documented a phenotype similar to that found in autism spectrum disorders (ASD). These studies suggest that significant alterations in Zn metabolism may be an important nutritional component in the development of ASD. MATERIALS & METHODS: The idea that prenatal zinc deficiency may be to blame is cursorily challenged...
2017: Iranian Journal of Child Neurology
Yuan Sheng Huang, Qiang An, Bin Zhao, Qing Hao Lv, Jing Song Guo
The potential for aerobic NO2(-) removal by Alcaligenes faecalis strain NR was investigated. 35 mg/L of NO2(-)-N was removed by strain NR under aerobic conditions in the presence of NH4(+). (15)N-labeling experiment demonstrated that N2O and N2 were possible products during the aerobic nitrite removal process by strain NR. The key enzyme genes of nirK, norB and nosZ, which regulate the aerobic nitrite denitrification process, were successfully amplified from strain NR. The gene sequence analysis indicates that copper-containing nitrite reductase (NIRK) and periplasmic nitrous oxide reductase (NOSZ) were both hydrophilic protein and the transmembrane structures were absent, while nitric oxide reductase large subunit (NORB) was a hydrophobic and transmembrane protein...
September 6, 2017: Archives of Microbiology
Ling-Xin Wei, Xiao-Ming Deng, Lei Wang, Jing-Hu Sui, Juan Zhi, Chao Wen, Jin Xu, Ju-Hui Liu
Objective To investigate the effect of intravenous dexmedetomidine injection(1 μg/kg)on the intubating conditions after inhalation induction with sevoflurane 8% and nitrous oxide(N2O)50% in children. Methods Totally 122 patients aged 4-10 years with an American Society of Anesthesiologists physical statusⅠ undergoing elective plastic surgery under general anesthesia were randomly divided to dexmedetomidine group(intraveneously injected with dexmedetomidine 1μg/kg)and control group(injected with normal saline)by using the random sampling table...
August 20, 2017: Zhongguo Yi Xue Ke Xue Yuan Xue Bao. Acta Academiae Medicinae Sinicae
P Laville, S Bosco, I Volpi, G Virgili, S Neri, D Continanza, E Bonari
The assessment of nitrous oxide (N2O) fluxes from agricultural soil surfaces still poses a major challenge to the scientific community. The evaluations of integrated soil fluxes of N2O are difficult owing to their lower emissions when compared with CO2. These emissions are also sporadic as environmental conditions act as a limiting factor. A station prototype was developed to integrate annual N2O and CO2 emissions using an automatic chamber technique and infrared spectrometers within the LIFE project (IPNOA: LIFE11 ENV/IT/00032)...
September 4, 2017: Environmental Monitoring and Assessment
Rui Tao, Steven A Wakelin, Yongchao Liang, Baowei Hu, Guixin Chu
The effects of consecutive application of chemical fertilizer with or without organic fertilizer on soil N2O emissions and denitrifying community structure in a drip-irrigated field were determined. The four fertilizer treatments were (i) unfertilized, (ii) chemical fertilizer, (iii) 60% chemical fertilizer plus cattle manure, and (iv) 60% chemical fertilizer plus biofertilizer. The treatments with organic amendments (i.e. cattle manure and biofertilizer) reduced cumulative N2O emissions by 4.9-9.9%, reduced the N2O emission factor by 1...
August 31, 2017: Science of the Total Environment
F Camacho-Morell, M J Romero-Martín
OBJECTIVE: To assess knowledge, wish for inclusion and implementation of normal childbirth care protocols at La Ribera University Hospital, the reason why they are not applied, and to assess the attendance at antepartum training activities. MATERIAL AND METHOD: Cross-sectional descriptive study. They were carried out 186 surveys by convenience sampling to pregnant women attending fetal well-being control at hospital between 2014 and 2015. They were collected data about knowledge, wish for inclusion, compliance of protocols and reasons for non-compliance, and attendance at antepartum training activities...
August 30, 2017: Revista de Calidad Asistencial: Organo de la Sociedad Española de Calidad Asistencial
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"