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991.
Proactive corporations have been looking at methods to determine the real costs of doing business, including environmental costs using environmental cost accounting (ECA) methodology. Many companies do not track or measure environmental costs and therefore do not know their true environmental costs. Unfortunately, conventional accounting practices rarely tease out environmental costs, and the costs associated with environmental compliance remain hidden in general overhead accounts. ECA can bring the world of business and the environment closer. When we have a better handle on environmental costs, we can use this information to better prioritize environmental projects, identify cost improvement projects, and allocate environmental costs to products. In this article we explore how some companies approach ECA and show how to initiate an ECA program. 相似文献
992.
Marta Monari Gian Paolo Serrazanetti Jurgen Foschi Valerio Matozzo Maria Gabriella Marin Otello Cattani 《Marine Biology》2007,151(3):1059-1068
The effects of different salinity levels (28, 34 and 40‰) on functional responses of Chamelea gallina haemocytes were evaluated in a two part study dealing with modulations of immune parameters. This part (Part II) of the study
was focused on the superoxide dismutase (SODs) activity and expression in haemocyte lysate and cell-free haemolymph. Results
of this study established that the exposure of C. gallina specimens at 40‰ salinity provoked a decrease in Mn-SOD and Cu/Zn-SOD activities in haemocyte lysate suggesting a declining
superoxide anion generation at the highest salinity tested. Expression of MnSOD was coherent with activity values, while Cu/ZnSOD
showed two immunoreactive bands. The former corresponds to the cytosolic Cu/Zn-SOD (16 kDa) was not coherent with the enzyme
activity and the second (28–30 kDa) probably attributed to EC-SOD. In cell-free haemolymph, Mn-SOD activity decrease and Cu/Zn-SOD
activity increase at 40‰ were observed, likely due to EC-SOD contribution, strongly induced at the same salinity. After EC-SOD
detection with two different antibody, we postulate that the EC-SOD like-protein band (29 kDa) may be constitute partly by
EC-SOD and probably by Cu/Zn-SOD dimeric form not completely dissociated under reducing condition or a Cu/Zn-SOD degenerated
but still recognized by antibody. The cell-free haemolymph increase of EC-SOD at high salinity values plays an important role
in immune defence of C. gallina. According to the conclusion of Part I of this study, our data confirmed the destabilizing effect of 40‰ salinity on haemocyte
functionality, while to 28‰ exposure, data don’t confirm its stressful action as instead stated by results of Part I. Further
studies are necessary to clear up this discrepancy. 相似文献
993.
Valerio Matozzo Marta Monari Jurgen Foschi Gian Paolo Serrazanetti Otello Cattani Maria Gabriella Marin 《Marine Biology》2007,151(3):1051-1058
In the present study, the effects of differing salinities on some important functional responses of haemocytes from the clam,
Chamelea gallina, were investigated. The animals were kept for 7 days at 28‰ (hyposalinity), 34‰ (control) and 40‰ salinity (hypersalinity),
and total haemocyte count (THC), haemocyte volume, phagocytosis, lysozyme-like activity (in both haemocyte lysate and cell-free
haemolymph) were measured. The survival-in-air test was also performed. Clams kept at 28‰ showed significantly increased THC
with respect to animals kept at 34 and 40‰. The analysis of haemocyte size frequency distribution highlighted that in clams
kept at 28‰ the haemocyte fraction of about 5 μm in diameter and 50–100 femtolitre in volume increased markedly. Conversely,
in animals kept at 40‰ an increase was observed in the haemocyte fraction having about 8–10 μm diameter and 400–500 femtolitre
volume. Higher phagocytic activity was recorded in haemocytes from control clams, with respect to that of clams kept at 28
and 34‰. Lysozyme-like activity in haemocyte lysate was shown to increase significantly in animals kept at 28‰ with respect
to that of clams kept at 40‰, whereas enzyme activity in cell-free haemolymph from clams kept at 34‰ was significantly higher
with respect to that of clams maintained at 40‰. A relationship between phagocytosis and lysozyme secretion is suggested.
The resistance to air exposure of clams kept at 28 and 40‰ was shown to decrease significantly; LT50 values fell from 7 days in clams kept at 34‰ to 4 and 5 days in those kept at 28 and 40‰, respectively. Results demonstrated
that salinity values far from 34‰ affects the functional responses of haemocytes and reduce the resistance of clams to exposure
to air. 相似文献
994.
Toxicity attenuation of olive mill wastewater in soil slurries 总被引:1,自引:0,他引:1
Maria Letizia Colarieti Giuseppe Toscano Guido Greco Jr 《Environmental Chemistry Letters》2006,4(2):115-118
Olive mill wastewaters are toxic for plants and microbes due to their high polyphenol content. We studied the effect of agricultural soil as a natural catalyst to promote polyphenol oxidation and polymerization, and in turn detoxify olive mill wastewaters. We show that model polyphenols are fully converted in soil slurries. Their products show no toxicity to the growth of a typical soil bacterium, Bacillus cereus, and reduced phytotoxicity in germination tests with English cress seeds. Those findings are promising for the sustainable treatment of olive wastewater in aerated soil slurries. 相似文献
995.
Iztok Arčon Arnold Pastrello Laura Catalano Maria De Nobili Pierpaolo Cantone Liviana Leita 《Environmental Chemistry Letters》2006,4(4):191-194
The fate of cyanides in soil is strongly influenced by the formation of Fe cyanides, which can interact with organic and inorganic colloids and precipitate as stable compounds. Scarce information is available on the capacity of humic acids to interact with cyano-complexes and thus affect the leaching and prevent the risk of contamination of watertable. Here we show that interaction between humic acids (HAs) and ferricyanide complex led to a formation of ferricyanide-humo micelles, and that the interaction did not imply changes in the original structure of ferricyanide complex. 相似文献
996.
997.
Brood guarding animals face many critical trade-offs. Sand goby males (Pomatoschistus minutus) build nests with larger openings during low oxygen conditions, presumably to enhance ventilation. However, this may make
the nest easier for egg predators to detect and harder for guarding males to defend. Manipulating oxygen level and predator
presence (a small crab) for small and large males, we found support for a parental trade-off between fanning and nest defense.
An increased fanning activity resulted in less time for guarding. Small males and males in low oxygen showed a higher fanning
expenditure than large males and males in high oxygen, but surprisingly, filial cannibalism did not differ between these groups.
Males built larger nest openings in low than high oxygen. However, males in both high and low oxygen treatments reduced their
nest opening size in the presence of a predator, again indicating an important trade-off between ventilation and nest defense. 相似文献
998.
Nicola?SainoEmail author Maria?Romano Roberto?Sacchi Paola?Ninni Paolo?Galeotti Anders?Pape?M?ller 《Behavioral ecology and sociobiology》2003,54(5):465-471
Some sexual selection models envisage exaggerated male secondary sexual characters to be costly and therefore reliable indicators of the quality of potential mates to choosy females. If male secondary sexual characters have a natural selection cost, they may be linked to each other by reciprocally constraining relationships that would prevent individual males from increasing their level of multiple signaling. Barn swallow (Hirundo rustica) males have at least two costly signals relevant to socio-sexual interactions: tail length and song. Under the hypothesis that a trade-off exists between male signals, we manipulated the maintenance cost of tail ornaments to test whether this reduced the quantity and quality of song, a condition-dependent, phenotypically plastic signal. Contrary to our expectation, tail elongation had no effect on singing activity and song complexity. However, tail-elongated males produced songs with longer terminal parts ('rattles'). Long rattles are associated with highly competitive social contexts and high circulating levels of testosterone, suggesting that tail-elongated males were more frequently involved in either male-male aggressive or inter-sexual interactions. Therefore, this study shows that males are not displaying multiple signals at the maximum possible level, implying that this system is open to unreliable communication. However, long-term trade-offs between signal expression and viability may prevent males from displaying both signals at higher rates.Communicated by: M. Webster 相似文献
999.
Differential pulmonary inflammation and in vitro cytotoxicity of size-fractionated fly ash particles from pulverized coal combustion 总被引:3,自引:0,他引:3
Gilmour MI O'Connor S Dick CA Miller CA Linak WP 《Journal of the Air & Waste Management Association (1995)》2004,54(3):286-295
Exposure to airborne particulate matter (PM) has been associated with adverse health effects in humans. Pulmonary inflammatory responses were examined in CD1 mice after intratracheal instillation of 25 or 100 microg of ultrafine (< 0.2 microm), fine (< 2.5 microm), and coarse (> 2.5 microm) coal fly ash from a combusted Montana subbituminous coal, and of fine and coarse fractions from a combusted western Kentucky bituminous coal. After 18 hr, the lungs were lavaged and the bronchoalveolar fluid was assessed for cellular influx, biochemical markers, and pro-inflammatory cytokines. The responses were compared with saline and endotoxin as negative and positive controls, respectively. On an equal-mass basis, the ultrafine particles from combusted Montana coal induced a higher degree of neutrophil inflammation and cytokine levels than did the fine or coarse PM. The western Kentucky fine PM caused a moderate degree of inflammation and protein levels in bronchoalveolar fluid that were higher than the Montana fine PM. Coarse PM did not produce any significant effects. In vitro experiments with rat alveolar macrophages showed that of the particles tested, only the Montana ultrafine displayed significant cytotoxicity. It is concluded that fly ash toxicity is inversely related with particle size and is associated with increased sulfur and trace element content. 相似文献
1000.
In a study of polychlorinated biphenyls (PCB) in freeze-dried sediments from Swedish lakes, the samples were found to contain unexpectedly high concentrations of PCBs. In one of the lakes (Bj?rken), e.g. the concentration of PCB-28 was found to be 189 ng/g dw after freeze-drying compared to 7 ng/g dw after air-drying of the sediment and therefore our hypothesis was that the contamination had occurred during the freeze-drying procedure. Hence, a dry reference sediment (RS) was used in order to identify potential sources of PCB contamination. The investigation included freeze-drying of the dry RS in five different laboratories, exposure to the air in the freeze-drying room, storage at room temperature and air-drying in a certain fume hood and in a laminar flow clean bench. The pattern and concentrations of PCBs detected in the exposed RS were strongly influenced by low chlorinated PCB congeners under all of these conditions with exception for air-drying in the fume hood. Storage in the laboratory air resulted in a slight elevation in the concentrations of low chlorinated PCB congeners, whereas higher concentrations of all PCB congeners were observed after freeze-drying. In all experiments the contamination appeared to be due to adsorption of PCB from the laboratory air. On the basis of these findings we recommend that reference material be subjected to the entire procedure, including sample preparation, in order to monitor contamination and that a procedure involving solvent extraction of wet sediment samples is used, whenever possible, instead of procedures involving dry samples. 相似文献