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551.
Moukaram Tertuliano Jeffery K. Tomberlin Zeljko Jurjevic David Wilson Glen C. Rains W. J. Lewis 《Chemoecology》2005,15(2):89-95
Summary. The parasitic wasp Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) learns to associate odors with food resources and subsequently exhibits a characteristic food-seeking behavior when encountering the learned odor. Wasps so conditioned, learned and subsequently demonstrated an ability to distinguish among aflatoxigenic and non-aflatoxigenic Aspergillus flavus and A. parasiticus strains. The effects of fungal species, strain, age (5, 10-12, 20, and 30 d) and growth media (potato dextrose agar, peanut agar and corn agar) on the learning and recognition responses of the conditioned wasps were examined. The level of differentiation between fungal strains by conditioned wasps was lowest when working with 5-d-old fungal cultures but increased with age and generally peaked with 20-d-old fungi. Wasps responded generally stronger to the fungal strain conditioned to independent of growth media. This ability of parasitic wasps to learn and distinguish fungal odors can open new avenues in insect learning. 相似文献
552.
553.
Gary D. Lynne J. Walter Milon Michael E. Wilson 《Journal of the American Water Resources Association》1990,26(4):669-676
ABSTRACT: Scarcity combined with differences in values, beliefs, and attitudes can lead to behavior differences and conflicts over water. This paper develops an index for measuring potential conflict using survey information about water attitudes and beliefs of individuals in three groups in a Florida case study. The index helps in assessing the current capability of the institution to reduce conflict. The results suggest that the current institution is effective, but changes may help to streamline the consumptive-use permitting process, to improve educational programs, and to seek improved institutional arrangements to reduce future conflict over economic uses of water. 相似文献
554.
555.
D. Wilson Freshwater Andrew Hines Seth Parham Ami Wilbur Michelle Sabaoun Jennifer Woodhead Lad Akins Bruce Purdy Paula E. Whitfield Claire B. Paris 《Marine Biology》2009,156(6):1213-1221
Lionfish are popular aquarium fish from the Indo-Pacific that have invaded the western Atlantic. Two species, Pterois volitans and P. miles, were well established along the United States east coast before the first lionfish were reported from the Bahamas in 2004,
where they quickly dispersed throughout the archipelago by 2007. The source of the Bahamian lionfish invasion has been in
question because of the hypothesized low connectivity between Florida and Bahamas reef species as well as the temporal lag
in their arrival in the Bahamas. Mitochondrial control region haplotypes (680 bp) were determined and analyzed for lionfish
specimens from the Bahamas, North Carolina, and two sites within their native range (Indonesia and the Philippines). Exact
tests, pairwise F
st and AMOVA analyses all showed no significant differentiation between the Bahamas and North Carolina specimens. The similarity
between the Bahamas and North Carolina lionfish was also reflected in a minimum spanning network and neighbor-joining distance
tree generated from the data. Sequence analyses also revealed the presence of only Pterois volitans, as no P. miles were detected in the Bahamian sample. These results indicate that the source of the Bahamian lionfish is egg and larval dispersal
from the United States east coast population, and support previous models of reef fish dispersal that suggest a low level
of connectivity between the Bahamas and east coast of Florida. 相似文献
556.
A new mandibular sensor is presented here based on the use of a Hall sensor, attached to one mandible, opposite a magnet, attached to the other mandible. Changes in sensor voltage, proportional to magnetic field strength, and thus inter-mandibular angle, are recorded in a logger. This system was tested on seven captive Adélie penguins (Pygoscelis adeliae) and three gentoo penguins (Pygoscelis papua) during: (1) feeding trials on land, where birds were given known quantities and types of food; and (2) trials in water where birds were allowed to swim and dive freely. In addition, six free-living Magellanic penguins (Spheniscus magellanicus) were equipped with the system for single foraging trips. Angular signatures were looked for in instances when both captive and free-living birds might open their beaks, and it was discovered that five major behaviours could be identified: ingestion, breathing, calling, head shaking and preening. Captive feeding trials showed that prey mass could be determined with reasonable accuracy (r2=0.92), and there was some indication that prey type could be resolved if recording frequency were high enough. Vocalisations in Adélie penguins (arc calls) took <0.7 s for mean maximum beak angles of 4.2° (SD 1.3), and were distinguished by their relatively gradual change in beak angle and by their high degree of symmetry. Beak shakings were distinguishable by their short duration (multiple peaks of <0.5 s) and minimal maximum angle (<0.5°). Preening behaviour was apparent due to multiple decreasing peaks (angles <8°). Breathing could be subdivided into that during porpoising, where a characteristic double peak in beak angle was recorded, and that during normal surface rests between dives. During porpoising, only the primary peak (mean maximum beak angle 25.1°, SD 4.7) occurred when the bird was out of the water (mean maximum for second peak 5.9°, SD 4.1). During normal surface rests in free-living birds, breaths could be distinguished as a series of beak openings and closures, showing variation in amplitude and frequency according to an apparent recovery from the previous dive and preparation for the subsequent dive to come. The mandibular measuring system presented shows considerable promise for elucidating many hitherto intractable aspects of the behaviour of free-living animals. 相似文献
557.
558.
Omphalocele is one of the most common abdominal wall defects seen in the prenatal period. Once this diagnosis is confirmed, it is important to check the fetal karyotype and thoroughly assess the fetus for other malformations. Prenatal management involves serial assessment of fetal growth and prenatal testing to ensure fetal well-being. Closure of the abdominal wall and replacement of organs into the abdominal cavity can be done directly if the omphalocele is small or in a staged manner if the omphalocele is large. Successful outcomes for these neonates can be optimized with a multidisciplinary team approach to prenatal and postnatal management. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
559.
Charles A. Wilson David L. Nieland John W. Fleecer Antonio Todaro Ronald F. Malone Kelly A. Rusch 《Chemistry and Ecology》2013,29(3-4):321-340
The effects of cement consolidated phosphogypsum (PG) on marine organisms was investigated under natural conditions in four 1000 m2 estuarine ponds. Two ponds were seeded with 160 kg of PG arranged in aggregations of blocks and two ponds received similar mass of sand/cement blocks. Meiofauna were sampled quarterly and PG did not affect total meiofauna or major taxa (nematodes and copepods) density. Abundant species of copepods either were slightly increased in ponds with PG or were inconsistently affected. All ponds were drained after one year. Three species of macroinvertebrates and 15 species of fishes were collected. Diversity indices showed modest but inconsistent variation among ponds. Only Pond 1 (control) and Pond 4 (experimental) had similar species abundances and all ponds showed unique distributions of biomasses among species. Thus, no differences in community structure attributable to the presence of PG could be detected among benthic invertebrates, natant invertebrates, or fishes. 相似文献
560.
International projects frequently struggle with the dilemmas of community participation, whether the community in question
is the object of a development or aid intervention, or is to be persuaded to cooperate on a conservation project. This paper
discusses the challenges facing interventionists and the obstacles and opportunities that local people encounter as they come
into contact with exogenous conservation and development projects. The key issues presented can be summarized as legacy, legitimacy,
agency and communication. We argue that project planners need to understand the history of past interventions in order to
respond appropriately to local expectations. At the same time, the complexity of community leadership and representation complicates
the sometimes conflicting agendas of project developers and communities. Much depends on personal relations, individual agency,
and initiative. Finally, the physical means of communication—language, print and broadcast media, transport and telecommunications—are
important aspects to consider when assessing the limitations to community participation. Although there have been valuable
successes in international projects in Russia, as in other regions of the world, a better understanding of community participation
is needed to ensure more effective and sustainable means for engaging communities in project development and implementation.
This paper explores these questions through a locally-grounded analysis based on the academic research and practitioner experience
of the two authors in the remote home of a World Heritage site—the Kamchatka Peninsula, in the Russian Far East. 相似文献