1 Dokinos

Scott G Mariani Bibliography Mla

Abstract

The movements of some long-distance migrants are driven by innate compass headings that they follow on their first migrations (e.g., some birds and insects), while the movements of other first-time migrants are learned by following more experienced conspecifics (e.g., baleen whales). However, the overall roles of innate, learned, and social behaviors in driving migration goals in many taxa are poorly understood. To look for evidence of whether migration routes are innate or learned for sea turtles, here for 42 sites around the world we compare the migration routes of >400 satellite-tracked adults of multiple species of sea turtle with ∼45 000 Lagrangian hatchling turtle drift scenarios. In so doing, we show that the migration routes of adult turtles are strongly related to hatchling drift patterns, implying that adult migration goals are learned through their past experiences dispersing with ocean currents. The diverse migration destinations of adults consistently reflected the diversity in sites they would have encountered as drifting hatchlings. Our findings reveal how a simple mechanism, juvenile passive drift, can explain the ontogeny of some of the longest migrations in the animal kingdom and ensure that adults find suitable foraging sites.

Abstract

This work deals with the preparation of poly(urethane acrylates) by using two different polymerization techniques. Namely, the classical batch procedure has been compared with frontal polymerization (FP). A thorough study on the effect of initiator type, concentration, and on the velocity of the front and its maximum temperature has been carried out. Moreover, two different synthetic ways have been studied: the one step poly(urethane acrylate) preparation starting directly from 1,6 diisocyanato hexane and 2-hydroxyethyl acrylate, and the two step procedure consisting of the synthesis of the corresponding diurethane diacrylate and of its subsequent polymerization. The first method has the advantage of being faster but some caution is necessary due to the excessive heat that is generated if the reaction conditions are not properly chosen. The second approach requires a further step but has the advantage of being more controlled. DSC analysis did not show any significant difference by comparing the thermal properties of the materials obtained by the two techniques (batch and FP). However, since FP runs are very easy and fast to be performed, FP should be seriously taken into proper account when these materials have to be prepared. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3344–3352, 2008

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