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Tobacco has not only negative effects on health; it also has an environmental impact. Each year, tobacco production requires 22 000 billion liters of water, mainly for cultivation. Thousands hectares of forestland are cleared annually, largely for the desiccation of tobacco leaves. Cigarette production is responsible for 84 million tons of CO2 equivalent. This paper reviews the environmental impact of the production and consumption of cigarettes from tobacco growing and manufacturing to consumption and waste production, and compares it with current consumption data.Le tabac a non seulement des effets négatifs sur la santé, mais également un impact environnemental. La production de tabac nécessite 22 000 milliards de litres d’eau par année, principalement pour la culture. La surface de déforestation, en grande partie pour le processus de dessiccation des feuilles de tabac concerne des milliers d’hectares par an. La production de cigarettes est à l’origine de 84 millions de tonnes d’équivalent CO

Summary Introduction The international ICALIC initiative aims at developing a new indirect calorimeter according to the needs of the clinicians and researchers in the field of clinical nutrition and metabolism. The project initially focuses on validating the calorimeter for use in mechanically ventilated acutely ill adult patient. However, standard methods to validate the accuracy of calorimeters have not yet been established. This paper describes the procedures for the in-vitro tests to validate the accuracy of the new indirect calorimeter, and defines the ranges for the parameters to be evaluated in each test to optimize the validation for clinical and research calorimetry measurements. Methods Two in-vitro tests have been defined to validate the accuracy of the gas analyzers and the overall function of the new calorimeter. 1) Gas composition analysis allows validating the accuracy of O2 and CO2 analyzers. Reference gas of known O2 (or CO2) concentration is diluted by pure nitrogen gas to achieve predefined O2 (or CO2) concentration, to be measured by the indirect calorimeter. O2 and CO2 concentrations to be tested were determined according to their expected ranges of concentrations during calorimetry measurements. 2) Gas exchange simulator analysis validates O2 consumption (VO2) and CO2 production (VCO2) measurements. CO2 gas injection into artificial breath gas provided by the mechanical ventilator simulates VCO2. Resulting dilution of O2 concentration in the expiratory air is analyzed by the calorimeter as VO2. CO2 gas of identical concentration to the fraction of inspired O2 (FiO2) is used to simulate identical VO2 and VCO2. Indirect calorimetry results from publications were analyzed to determine the VO2 and VCO2 values to be tested for the validation. Results O2 concentration in respiratory air is highest at inspiration, and can decrease to 15% during expiration. CO2 concentration can be as high as 5% in expired air. To validate analyzers for measurements of FiO2 up to 70%, ranges of O2 and CO2 concentrations to be tested were defined as 15–70% and 0.5–5.0%, respectively. The mean VO2 in 426 adult mechanically ventilated patients was 270 ml/min, with 2 standard deviation (SD) ranges of 150–391 ml/min. Thus, VO2 and VCO2 to be simulated for the validation were defined as 150, 250, and 400 ml/min. Conclusion The procedures for the in-vitro tests of the new indirect calorimeter and the ranges for the parameters to be evaluated in each test have been defined to optimize the validation of accuracy for clinical and research indirect calorimetry measurements. The combined methods will be used to validate the accuracy of the new indirect calorimeter developed by the ICALIC initiative, and should become the standard method to validate the accuracy of any future indirect calorimeters.

ambient temperature in the range of −15–12 °C according to the standard UNI EN 14511/2011. The results show the possibility to reach an optimum of the COP by varying the ejector area, once the other parameters are fixed, as a consequence of the ejector regulation on the pressures at the inlet and outlet of the compressor. © 2017 Elsevier Ltd and IIR, compressor frequency in the range of 30–60 Hz, Carbon dioxide is becoming an interesting option also for HVAC heating appliances due to its eco-friendly characteristics. The incurrence of transcritical cycles makes the use of ejectors attractive to improve performance. Part load conditions and varied ambient temperatures imply the use of variable geometry systems of appropriate design to keep their efficiency high. This paper investigates experimentally a multi-ejector air-to-water CO2 heat pump for heating needs, measuring the performance of the system and of each component under partial and full load conditions. A sensitivity analysis was run varying, separately or in a combined way, the following parameters or operating conditions: ejector area ratio in a range of 33.1–86.6%