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111.
We propose a framework to facilitate the evaluation of the impacts of shale gas infrastructures (well pads, roads, and pipelines) on land cover features, especially with regards to forest fragmentation. We used a geographic information system and realistic development scenarios largely inspired by the PA (United States) experience, but adapted to a region of QC (Canada) with an already fragmented forest cover and a high gas potential. The scenario with the greatest impact results from development limited by regulatory constraints only, with no access to private roads for connecting well pads to the public road network. The scenario with the lowest impact additionally integrates ecological constraints (deer yards, maple woodlots, and wetlands). Overall the differences between these two scenarios are relatively minor, with <1 % of the forest cover lost in each case. However, large areas of core forests would be lost in both scenarios and the number of forest patches would increase by 13–21 % due to fragmentation. The pipeline network would have a much greater footprint on the land cover than access roads. Using data acquired since the beginning of the shale gas industry, we show that it is possible, within a reasonable time frame, to produce a robust assessment of the impacts of shale gas extraction. The framework we propose could easily be applied to other contexts or jurisdictions.  相似文献   
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The gas-transport function of red blood cells which have incorporated inositol hexaphosphate is significantly improved by fusion with effector-loaded lipid vesicles. “Right-shifts” of the O2-binding curves of inositol hexaphosphate-loaded red blood cells with half-saturation pressures at 37 °C up to 98 mmHg are observed. The transformation of 56% of the intracellular haemoglobin into the low affinity state corresponds to an optimum increase of the O2-release capacity of 270%. The CO2 transport is also correspondingly enhanced. The treated red blood cells show no inositol hexaphosphate depletion during a reasonable time.  相似文献   
116.
The process design of a 10–20 MWth Synthetic Natural Gas (SNG) production process from wood has been performed. Combining process modelling and process integration techniques, this study proceeds via the following stages:
• thermodynamic modelling: mass, energy balances and simulation of the wood gasification, the methanation and the purification units;
• process integration that identifies the energy saving opportunities and prepares a thermo-economic optimization.
This work demonstrates that the process can transform wood into pipeline quality methane with a thermal efficiency of 57.9% based on the Lower Heating Value (LHV). The process integration study shows that the heat surplus of the process can be used to almost satisfy the mechanical work required by the process; only 7% of the mechanical needs should come from an external source.  相似文献   
117.
We investigated the ontogeny of responses to scent marks in immature terrestrial salamanders (Salamandra lanzai) that inhabit the southwest Alps. In this species, sexual maturity is usually reached at about 8 years, and adults exhibit territoriality. One should expect territoriality to take place largely before the acquisition of sexual maturity if sexual competition is not the main force driving territoriality. However, both the difficulties for inexperienced animals to find a suitable territory and size-related competition may delay the acquisition of territoriality in juveniles. We performed choice tests with juveniles belonging to two age groups (1±1 years old versus 4±1 years old). Each focal animal was offered, in random order, the choice between two shelters, one without scent and the other containing one of the following scents: own, same-aged animal, a juvenile belonging to the other age group, or adult female. We also performed choice tests with adult females for which the scents of two juveniles belonging to a different age group were successively offered in a random order. Older juveniles were strongly attracted toward their own shelter and mostly avoided the shelters that contained the scent of juveniles of about the same age and of adult females. Adult females avoided the scents of older juveniles but not younger juveniles. These results therefore suggest that older juveniles use territorial marking. Conversely, young juveniles behaved randomly with respect to their own scents and to those of a same-aged juvenile, and they were significantly attracted towards the odor of an older animal, especially adult females. Both older juveniles and adult females displayed a random behavior toward the scents of young juveniles. Our results suggest that young juveniles do not defend territories but use spaces occupied by older individuals.Communicated by A. Mathis  相似文献   
118.
V, Co, Cu, Zn, As, Rb, Sr, Ag, Cd, Ba, Pb, Bi and U have been analysed by inductively coupled plasma sector field mass spectrometry in various sections of a dated snow/ice core drilled at an altitude of 6542 m on the Sajama ice cap in Bolivia. The analysed sections were dated from the Last Glacial Stage ( approximately 22,000 years ago), the Mid-Holocene and the last centuries. The observed variations of crustal enrichment factors (EFc) for the various metals show contrasting situations. For V, Co, Rb, Sr and U, EFc values close to unity are observed for all sections, then showing that these elements are mainly derived from rock and soil dust. For the other metals, clear time trends are observed, with a pronounced increase of EFc values during the 19th and 20th centuries. This increase shows evidence of metal pollution associated with human activity in South America. For Pb an important contribution was from gasoline additives. For metals such as Cu, Zn, Ag and Cd an important contribution was from metal production activities, with a continuous increase of production during the 20th century in countries such as Peru, Chile and Bolivia.  相似文献   
119.
Summary. The first identification of a sex pheromone of a pine sawfly (Hymenoptera, Diprionidae) dates back almost thirty years. Since then, female-produced pheromones of over twenty diprionid species have been investigated by solvent extraction followed by separation and identification. However, no study has shown what the females actually release. Collection of airborne compounds using absorbtion on charcoal filter as well as solid phase microextraction (SPME) followed by analysis employing gas chromatography combined with mass spectrometry (GC-MS), revealed an unusual system in Diprion pini, in which the pheromone precursor alcohol, 3,7-dimethyl-2-tridecanol, is released together with acetic, propionic, butyric and isobutyric acids. The corresponding acetate, propionate and butyrate esters of 3,7-dimethyl-2-tridecanol were also found in the samples. All esters were electrophysiologically active, and the propionate and isobutyrate were attractive in trapping experiments. Based on these and earlier reported results, it seems that at least in part of its range, the pheromone response of D. pini is not very specific with regard to the functional group, as long as this is an ester.  相似文献   
120.
The Lascaux Cave contains a remarkable set of paintings from the Upper Palaeolithic. Shortly after discovery in 1940, the cave was modified for public viewing and, in 2001, was invaded by a Fusarium solani species complex. Benzalkonium chloride was used from 2001 to 2004 to eliminate the fungal outbreak. In this study, we carried out a sampling in most of the cave halls and galleries. Sequence analysis and isolation methods detected that the most abundant genera of bacteria were Ralstonia and Pseudomonas. We suggest that, as a result of years of benzalkonium chloride treatments, the indigenous microbial community has been replaced by microbial populations selected by biocide application.  相似文献   
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