To develop an accurate measurement network of greenhouse gases, instruments in the field need to be stable and precise and thus require infrequent calibrations and a low consumption of consumables. ...For about 10 years, cavity ring-down spectroscopy (CRDS) analyzers have been available that meet these stringent requirements for precision and stability. Here, we present the results of tests of CRDS instruments in the laboratory (47 instruments) and in the field (15 instruments). The precision and stability of the measurements are studied. We demonstrate that, thanks to rigorous testing, newer models generally perform better than older models, especially in terms of reproducibility between instruments. In the field, we see the importance of individual diagnostics during the installation phase, and we show the value of calibration and target gases that assess the quality of the data. Finally, we formulate recommendations for use of these analyzers in the field.
During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO
2
) ...exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO
2
seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO
2
gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO
2
cycles from 48 European stations were available for 2017 and 2018. Earlier data were retrieved for comparison from international databases or national networks. Here, we show that the usual summer minimum in CO
2
due to the surface carbon uptake was reduced by 1.4 ppm in 2018 for the 10 stations located in the area most affected by the temperature anomaly, mostly in Northern Europe. Notwithstanding, the CO
2
transition phases before and after July were slower in 2018 compared to 2017, suggesting an extension of the growing season, with either continued CO
2
uptake by photosynthesis and/or a reduction in respiration driven by the depletion of substrate for respiration inherited from the previous months due to the drought. For stations with sufficiently long time series, the CO
2
anomaly observed in 2018 was compared to previous European droughts in 2003 and 2015. Considering the areas most affected by the temperature anomalies, we found a higher CO
2
anomaly in 2003 (+3 ppm averaged over 4 sites), and a smaller anomaly in 2015 (+1 ppm averaged over 11 sites) compared to 2018.
This article is part of the theme issue ‘Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.
This study examines whether voice identification performance is influenced whilst processing voice identity information by the presence of non-verbal vocalizations such as laughter. Ninety-six ...participants were exposed to an auditory event of 45 seconds in length presenting verbal and non-verbal information, including laughter. After a delay of 5 minutes, participants took part in a voice line-up manipulated for laughter (speech only, laughter only, or speech and laughter) and target presence (target present or target absent). Supporting the first hypothesis, participants' performance was significantly worse in the speech alone condition compared with both laughter conditions (laughter alone and laughter with speech). Further, identification performance was best in the laughter only condition. In addition, participants correctly rejected the line-up significantly more in the speech and laughter condition than in the speech alone or laughter alone conditions. Findings are discussed in terms of their implications for real-life earwitness identification parades.
Aims: To estimate the general and specific incidence of occupational asthma in France in 1996–99; and to describe the distribution of cases by age, sex, suspected causal agents, and occupation. ...Methods: New cases of occupational asthma were collected by a national surveillance programme, based on voluntary reporting, named Observatoire National des Asthmes Professionnels (ONAP), involving a network of occupational and chest physicians. For each case, the reporting form included information on age, sex, location of workplace, occupation, suspected causal agent, and methods of diagnosis. Estimates of the working population, used to calculate incidence rates by age, sex, region, and occupation, were obtained from the Institut National de la Statistique et des Etudes Economiques (INSEE) and from the French Securite Sociale statistics. Results: In 1996–99, 2178 cases of occupational asthma were reported to the ONAP, giving a mean annual rate of 24/million. Rates in men were higher than rates in women (27/million versus 19/million). The highest rate was observed in the 15–29 years age group (30/million). The most frequently incriminated agents were flour (20.3%), isocyanates (14.1%), latex (7.2%), aldehyde (5.9%), persulphate salts (5.8%), and wood dusts (3.7%). The highest risks of occupational asthma were found in bakers and pastry makers (683/million), car painters (326/million), hairdressers (308/million), and wood workers (218/million). Conclusion: Despite likely underreporting, the number of cases of occupational asthma reported to the ONAP was approximately twice the number of compensated cases over the same period. The relevance of the programme is confirmed by the reproducibility of the results year after year, and its consistency with other surveillance programmes. The ONAP programme is useful for the identification of targets for primary prevention.
To develop an accurate measurement network of greenhouse gases, instruments in the field need to be stable and precise and thus require infrequent calibrations and a low consumption of consumables. ...For about 10 years, cavity ring-down spectroscopy (CRDS) analyzers have been available that meet these stringent requirements for precision and stability. Here, we present the results of tests of CRDS instruments in the laboratory (47 instruments) and in the field (15 instruments). The precision and stability of the measurements are studied. We demonstrate that, thanks to rigorous testing, newer models generally perform better than older models, especially in terms of reproducibility between instruments. In the field, we see the importance of individual diagnostics during the installation phase, and we show the value of calibration and target gases that assess the quality of the data. Finally, we formulate recommendations for use of these analyzers in the field.
Cigarette smoking is associated with acute increase in arterial pressure due to systemic vasoconstriction and decreased skin and coronary blood flow. Virtually all cardiovascular effects of cigarette ...smoking are due to nicotine. However, whether nicotine also affects the renal circulation and function in humans is at present unknown.
In the current study the acute effects of a 4-mg nicotine gum on arterial pressure, heart rate as well as renal haemodynamics and function were assessed in non-smokers and chronic smokers.
In non-smokers, mean arterial pressure (+8 +/- 1 mmHg, P<0.001) and heart rate (+13 +/- 3 beats/min, P<0.001) increased whereas effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) decreased by 15 +/- 4% and 14 +/- 4% respectively; in addition, urinary cyclic GMP decreased by 51 +/- 12% in response to nicotine administration. In smokers, mean arterial pressure and heart rate increased similarly; however, in contrast with non-smokers, ERPF and GFR remained unchanged whereas urinary cyclic GMP rose by 87 +/- 43%. Changes in ERPF induced by nicotine were positively correlated with changes in urinary cyclic GMP.
These findings indicate that nicotine administration is associated with renal vasoconstriction in healthy non-smokers, possibly through alteration of a cyclic-GMP-dependent vasoactive mechanism. Tolerance to the renal effect of nicotine was observed in chronic smokers, despite the maintenance of the systemic response to nicotine.
Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring ...system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1σ) at 1 Hz and ± 1 ppm (1σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements.
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