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Accurate estimates of methane (CH4) fluxes from restored peatlands are needed to inform emission factor estimations and reporting. Flux measurements are usually taken during the daytime but such measurements may provide biased estimates of overall CH4 emissions if night-time fluxes differ from daytime fluxes. Diurnal variations in CH4 fluxes have been reported for a range of peatland types, but not for restored raised bogs which are important carbon stores in some countries. To help fill this knowledge gap, we investigated diurnal variations in CH4 emissions from a restored raised bog. CH4 fluxes from a restored raised bog were measured in two 24-hr field campaigns using flux chambers. Carbon dioxide (CO2) fluxes were also monitored, as were a suite of complementary environmental variables. Night-time CH4 fluxes were significantly greater than daytime fluxes during both campaigns, by 10.4% and 36.1%, respectively. In Campaign 1 air temperature was the best predictor of CH4 fluxes, whereas in Campaign 2 net ecosystem exchange (NEE) values were the best predictor. This study shows that diurnal variations in CH4 fluxes exist in a restored peatland and that current approaches biased to daytime measurements will underestimate CH4 emissions from restored peatlands to the atmosphere. [ABSTRACT FROM AUTHOR]

Summary: Objective: The aim of this study was to determine the effects of obesity on the waking diurnal testosterone and dehydroepiandrosterone (DHEA) cycles in obese middle-aged male subjects. Methods: Saliva samples were collected at awakening and every 3 hours from 9:00 to 21:00hours on 2 consecutive days in eight obese non-diabetic and eight healthy non-obese control men. Results: Saliva parameters showed day-to-day consistency, with an overall diurnal decline, except for testosterone in the obese group. Saliva testosterone concentrations were significantly lower (P <0.05) at awakening, 9:00 and 12:00hours in obese versus control subjects. No significant differences were observed in saliva DHEA concentrations between the obese and control subjects at any time of day. Conclusion: The results of this investigation indicate that obesity alone does not affect the concentrations or the diurnal pattern of DHEA in middle-aged men, whereas the diurnal pattern of testosterone appears altered in this population, with significantly lower values during the first part of the day. [Copyright &y& Elsevier]

En juin 1984 a été mise en place une nouvelle modulation horaire des tarifs téléphoniques, dans le but de réduire l'amplitude de la pointe de trafic interurbain du soir dont le niveau devenait supérieur à celui de la pointe du matin. L'impact de cette réforme tarifaire sur la répartition horaire du trafic et sur les recettes a été évalué, avant sa mise en place, à l'aide d'un modèle économétrique ajusté sur des observations issues d'expériences analogues mises en œuvre en RFA et en Suisse. Ce modèle, fondé sur la théorie des choix probabilistes, emprunte la formulation du modèle Logit adaptée au cas d'un ensemble continu d'options (les instants de la journée), et permet de simuler les transferts de trafic induits par des variations de la tarification horaire. Les observations faites depuis juin 1984 ont permis de constater les effets réels de la réforme tarifaire sur le trafic et de les comparer aux prévisions du modèle. Les écarts sont relativement faibles sur la période 18 h -20 h 30 (en particulier la baisse de la pointe de 20 h est conforme aux prévisions), mais plus importants en fin de soirée où l'on note une augmentation de trafic plus élevée que prévue. Ces nouvelles observations ont permis de réajuster et d'améliorer le modèle; c'est cette nouvelle version qui est présentée ici. As the evening peakload of trunk traffic became higher than the morning one, a new time-of-day pricing was initiated in France on June 1985. The effects of this tariff change on the traffic profile and the telephone revenues were previously estimated, using an econometric model, fitted from traffic observations provided by similar experiments carried out in Germany and Switzerland. This model, based on probabilistic choice theory, uses the Logit formulation adapted to the case of a continuous set of options (times-of-day), and provides simulations of traffic trade-offs due to changes in the time-of-day pricing. Data collected since June 1984 enable us to measure the actual effects of the new tariffication. Compared with the model forecasts, these observations show a good fitting for the 6 p.m. to 8.30 p.m. period (the 8 p.m. peak-load decrease is consistent with the forecast); in the late evening however, traffic is higher than expected. These new data allowed us to improve the formulation and the fitting of the model; these recent developments are presented here. [ABSTRACT FROM AUTHOR]