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101.
Becky L. Williams Vanessa Lovenburg Christine L. Huffard Roy L. Caldwell 《Chemoecology》2011,21(3):131-141
Some pelagic marine larvae possess anti-predator chemical defenses. Occasionally, toxic adults imbue their young with their
own defensive cocktails. We examined paralarvae of the greater blue-ringed octopus (Hapalochlaena lunulata) for the deadly neurotoxin tetrodotoxin (TTX), and if present, whether TTX conferred protection to individual paralarvae.
Paralarvae of H. lunulata possessed 150 ± 17 ng TTX each. These paralarvae appeared distasteful to a variety of fish and stomatopod predators, yet
food items spiked with 200 ng TTX were readily consumed by predators. We conclude that TTX alone does not confer individual
protection to paralarvae of H. lunulata, and that they possess an alternative defense. In larger doses, tetrodotoxin is a deterrent to the predatory stomatopod Haptosquilla trispinosa (mean dose = 3.97 μg/g). This corresponds to 12–13 paralarvae per predator based on the TTX levels of the clutch we examined.
Thus, the basic assumption that individual paralarvae of H. lunulata are defended by TTX alone was disproved. Instead, functionality of TTX levels in paralarvae may arise through alternative
selective pathways, such as deterrence to parasites, through kin selection, or against predator species not tested here. 相似文献
102.
Summary. Although terrestrial turtles have served as a model for studies of olfactory neurophysiology, little is known about how they
use chemical information in an ecological sense. We tested whether box turtles (Terrapene carolina) use chemical information to distinguish between predatory and nonpredatory mammals. Box turtles in our study exhibited more
escape behavior when exposed to urine from a predator (coyote, Canis latrans) than when exposed to urine from a nonpredator (white-tailed deer, Odocoileus virginianus) or a blank control. Escape behavior is consistent with an antipredator response. In addition, the turtles decreased their
handling time for food when in the presence of urine from either species of mammal in comparison to the blank, indicating
that chemical cues from mammals in general may result in increased vigilance by terrestrial turtles. Examination of a variety
of response variables may be important for adequate assessment of the ecological role of chemosensory behavior. 相似文献
103.
104.
S.M. Eldridge C.R. Chen Z.H. Xu P.N. Nelson S.E. Boyd I. Meszaros K.Y. Chan 《Waste management (New York, N.Y.)》2013,33(11):2157-2169
Using solid state 13C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes. 相似文献
105.
106.
Grout formulations have been investigated in Nevada Nuclear Waste Storage Investigations Project, for possible nuclear waste repository sealing applications focused in the Yucca Mountain Area (in welded tuff). A shrinkage compensated cement was chemically modified with siliceous reactants to enhance the chemical compatibility with a siliceous tuff. Fluids in contact with the grouts were measured at 150 °C and 200 °C, and the solids were characterized. Well-crystallized Al-substituted tobermorite and truscottite were observed, and sometimes xonotlite as dominant cementitious phases. Comparisons of solid phases and solution phases are made with a second grout incorporating siliceous modifiers in a Class H cement. Exposures to 150 °C hydrothermal conditions have not produced significant detrimental mechanical behavior of the seal material. The thermal decomposition of ettringite, an expansive calcium sulfate aluminate hydrate, resulted in a small increase in the porosity of the grout, but on a very small fine scale. 相似文献
107.
Chakrabortty Rabin Pal Subodh Chandra Arabameri Alireza Ngo Phuong Thao Thi Chowdhuri Indrajit Roy Paramita Malik Sadhan Das Biswajit 《Environment, Development and Sustainability》2022,24(3):3558-3559
Environment, Development and Sustainability - 相似文献
108.
109.
In this paper we estimate a flexible form cost function of the aluminium industry in the USA and use our estimates to obtain derived demand curves for aluminium inputs such as electricity and bauxite. We then calculate the welfare gains arising from decreased energy use when the level of secondary recycling is increased. The process is repeated for several model specifications. All of our tests, however, yield similar results and indicate that substitution of scrap for only 5% of the bauxite presently used in US aluminium manufacturing would result in annual savings of close to a quarter of a billion dollars. 相似文献
110.