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Aversive conditioning is a promising but unproven non-lethal approach to reducing mammalian depredation on the eggs of ground-nesting birds, terrapins and sea turtles. This research tested the efficacy of oral estrogen concealed in a bland carrier as an aversive agent for wild-caught raccoons (Procyon lotor) under controlled conditions. Nine treatment group raccoons were given six estrogen-injected eggs every other day during a 14-day treatment phase, and then given a combination of two estrogen-injected eggs, two fresh eggs, and two carrier-only injected eggs every other day during a 14-day challenge phase. Nine control group animals received six carrier-only injected eggs every other day during the treatment phase, and then two fresh eggs and four carrier-only injected eggs every other day during the challenge phase. All treatment animals exhibited a conditioned food aversion (CFA) after 1–8 egg feedings (15–116 mg of estrogen per kilogram of body mass). All later sampled at least a few eggs, but they consumed fewer eggs than the control animals during both the treatment phase (p 0.05) comparably. Treatment animals gained less mass than control animals (p = 0.013), but there was no apparent relationship between estrogen intake and mass change (p = 0.912). Testes of treatment males were similar in volume and mass (p = 0.712) to those of control males. Treatment animals experienced higher frequencies of abnormal feces (p

Procyon lotor (Raccoon) is a major predator of beach-nesting and colonial waterbirds on the Virginia barrier islands. An understanding of water as a barrier to inter-island movement by Raccoons will be essential to effective management of these predators in this naturally fragmented coastal environment. We examined 4 independent lines of direct evidence for Raccoon movement between 1999 and 2007: 1) locations of recaptured, ear-tagged Raccoons on both the islands and the adjacent mainland, 2) overland movements of radio-collared Raccoons, 3) inter-island movements of radio-collared resident Raccoons, and 4) movements of translocated Raccoons. We recaptured 78 of 177 ear-tagged island Raccoons, all on the same island as the initial capture. We also tagged and released 65 mainland Raccoons, none of which was ever recaptured on an island. We often observed overland movements >1 km per day by radio-collared animals on both the islands and the mainland. Nevertheless, only 3 of 51 (6%) collared animals (2 males and 1 female) moved overwater from the location where they were captured. None of the 4 Raccoons radio-collared on the mainland moved to an island. Although Raccoons in this system are highly mobile, overwater movements seem to be infrequent events; only 3 of 234 tagged/ collared island individuals moved between islands, and none of the 69 tagged/collared mainland individuals moved to an island. Finally, we observed return movements by 22 of the 32 (69%) animals (11 males and 11 females) that were translocated either from the mainland to a nearby island or between adjacent islands. Translocated animals exhibited a much greater tendency than resident animals to make overwater crossings. In all cases of overwater movement, the water channels were relatively shallow and relatively slow moving. None of the 335 marked animals in this study crossed a tidal inlet. The mobility observed here is consistent with the idea that the distribution of Raccoons on the islands has expanded in recent decades. Predation management on these islands will require a strategic approach that takes into account both island isolation and Raccoon mobility.

We describe a method for making clay mimics of bird eggs. These eggs can be used in experiments that require many uniform, accurate artificial eggs. We developed methods and made about 1,000 clay eggs at a cost of $0.55 each.

The contributions of aircraft reconnaissance to the accuracy of tropical cyclone center positioning, motion, and intensity determinations are examined, along with their impact on the accuracy of track and intensity forecasting. The analyses concentrate on differences in cyclone position and intensity diagnosis, as well as track forecasting during periods when aircraft measurements were made versus times when aircraft data were not available. Northwest Pacific data for the period 1979–86, which contain over 200 tropical cyclone cases with approximately 5000 center fix positions, were used for the analyses. Aircraft versus no-aircraft situations are examined with respect to the class of satellite data that were available and for day versus night measurements. Differences in positioning and intensity estimates made from simultaneous independent satellite observations are also examined. Results show that satellite analysts operating independently frequently obtain large differences in their estimates...

We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view about chromatin structure has emerged, including its interrelationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded novel mechanistic and evolutionary insights about the functional landscape of the human genome. Together, these studies are defining a path forward to pursue a more-comprehensive characterisation of human genome function.

Publisher Summary This chapter discusses the representational specificity and concept learning. When a young child is fed by an adult, at first she assumes that all generally similar creatures, that is, all adults, would treat her equally well. With more experience, she comes to expect food from a smaller group of adults, such as all familiar adults, and then from a yet more specific class of creatures, such as mother, father, and grandmother (MFG). On the other hand, the child could initially expect feeding from a very specific set, mother only, and with experience generalize to female relatives (MG) and then to larger classes, such as MFG. Clearly, both approaches, starting with general classes or starting with specific classes, can produce appropriate results. Both converge toward an optimal level of generality. Even though the two approaches attain the same result, one could be more efficient. For instance, if one approach generally requires fewer examples before converging on the correct class, that method could be used in machine learning algorithms and would be expected to be used in natural systems.

RecQ helicases, including Saccharomyces cerevisiae Sgs1p and the human Werner syndrome protein, are important for telomere maintenance in cells lacking telomerase activity. How maintenance is accomplished is only partly understood, although there is evidence that RecQ helicases function in telomere replication and recombination. Here we use two-dimensional gel electrophoresis (2DGE) and telomere sequence analysis to explore why cells lacking telomerase and Sgs1p (tlc1 sgs1 mutants) senesce more rapidly than tlc1 mutants with functional Sgs1p. We find that apparent X-shaped structures accumulate at telomeres in senescing tlc1 sgs1 mutants in a RAD52- and RAD53-dependent fashion. The X-structures are neither Holliday junctions nor convergent replication forks, but instead may be recombination intermediates related to hemicatenanes. Direct sequencing of examples of telomere I-L in senescing cells reveals a reduced recombination frequency in tlc1 sgs1 compared with tlc1 mutants, indicating that Sgs1p is needed for tlc1 mutants to complete telomere recombination. The reduction in recombinants is most prominent at longer telomeres, consistent with a requirement for Sgs1p to generate viable progeny following telomere recombination. We therefore suggest that Sgs1p may be required for efficient resolution of telomere recombination intermediates, and that resolution failure contributes to the premature senescence of tlc1 sgs1 mutants., Author Summary Because telomeres are situated at the ends of chromosomes, they are both essential for chromosome integrity and particularly susceptible to processes that lead to loss of their own DNA sequences. The enzyme telomerase can counter these losses, but there are also other means of telomere maintenance, some of which depend on DNA recombination. The RecQ family of DNA helicases process DNA recombination intermediates and also help ensure telomere integrity, but the relationship between these activities is poorly understood. Family members include yeast Sgs1p and human WRN and BLM, which are deficient in the Werner premature aging syndrome and the Bloom cancer predisposition syndrome, respectively. We have found that the telomeres of yeast cells lacking both telomerase and Sgs1p accumulate structures that resemble recombination intermediates. Further, we provide evidence that the inability of cells lacking Sgs1p to process these telomere recombination intermediates leads to the premature arrest of cell division. We predict that similar defects in the processing of recombination intermediates may contribute to telomere defects in human Werner and Bloom syndrome cells., Yeast cells lacking the RecQ helicase Sgs1p show an accumulation of telomere recombination intermediates associated with premature senescence.

Methyl methoxymagnesium carbonate (Stiles' reagent) carboxylates butyrolactones in very high yield, and, with a new application of the Cope condensation for the introduction of the methylene group, permits the synthesis of α-methylenebutyrolactones in good overall yield.