Initial administration of 60% nitrous oxide (N2O) at 21°C ambient temperature (Ta) reduces core temperature (Tc) in rats, but tolerance develops to this hypothermic effect over several administrations. After additional N2O administrations, a hyperthermic overcompensation (sign-reversal) develops such that Tc exceeds control levels during N2O inhalation. This study investigated whether rats woul...

Fossil fuel combustion is the second largest anthropogenic source of nitrous oxide (N2O) after agriculture. The estimated global N2O flux from combustion sources, as well as from other sources, still has a large uncertainty. Herein, we characterize automobile sources using N2O isotopomer ratios (nitrogen and oxygen isotope ratios and intramolecular site preference of 15N, SP) to assess their co...

background & purpose: there are occupational hazards related to nitrous oxide (n2o) in hospitals operating and recovery rooms. these hazards include the decrease of mental performance and audio-visual ability, and reduced fertility, spontaneous abortion and neurological, renal and liver diseases. in this survey, the concentration of nitrous oxide in indoor air of hospitals operating and recover...

To understand the mechanisms underlying the increased N2O reductase activity in the Bradyrhizobium japonicum 5M09 mutant from enrichment culture under N2O respiration, we analyzed the expression of genes encoding denitrification reductases and regulators. Our results suggest a common regulation of nap (encoding periplasmic nitrate reductase) and nos (encoding N2O reductase).

The dynamics of N2O decomposition to gaseous nitrogen and oxygen over HZSM-5 catalysts with a low iron content (200 and 1000 ppm) was studied by the transient response method in the temperature range 523–653 K. The active catalysts were prepared from HZSM-5 with Fe in the framework on its steaming at 823 K followed by thermal activation in He at 1323 K. Two main steps were distinguished in the ...

OBJECTIVES To investigate the effective role of micro-organisms in producing N2O. METHODS The N2O in either urine samples inoculated with 24 microbial strains or urine samples from patients with urinary tract infections were measured. RESULTS Gram negative bacilli generally produced high amounts of nitrous oxide (N2O), whereas Gram positive cocci and yeasts did not. The production of N2O de...

This prospective study of 36 children, ages 44-93 months, receiving nitrous oxide-oxygen under standardized conditions during routine dental procedures was conducted to determine what influence eight selected dental procedures and three patient behaviors had on ambient nitrous oxide (N2O) levels in the dentist's breathing zone. Half the children received nitrous oxide-oxygen via a scavenging na...

Agriculture is the main source of terrestrial emissions of N2O, a potent greenhouse gas and the main cause of ozone layer depletion. The reduction of N2O into N2 by microorganisms carrying the nitrous oxide reductase gene (nosZ) is the only biological process known to eliminate this greenhouse gas. Recent studies showed that a previously unknown clade of N2O-reducers was related to the capacity...

[1] N2O, CH4 and CO2 soil-atmosphere exchange and controlling environmental factors were studied for a 3-month period (dry-wet season transition) at the Kakamega Rain forest, Kenya, Africa, using an automated measurement system. The mean N2O emission was 42.9 ± 0.7 mg N m 2 h 1 (range: 1.1–324.8 mg N m 2 h ). Considering the duration of dry and wet season the annual N2O emission was estimated a...