The apple snail, Pomacea canaliculata has made a tremendous threat to aquatic agricultural crops for many years. But safe and effective methods to eliminate them are still not available. Traditionally, pesticides are the most common way to kill apple snails. However, the occurrence of drug resistance and drug residual causes even more serious problems. The present study was conducted to evaluate the effectiveness of attractants to apple snails in the fields. The experiments included the effectiveness of different attractants and trap designs under different environmental conditions. It was found that attractants of banana pulp, chicken blood and condensed fish soluble were effective with at least 12-hour trapping time. The sizes of attracted snails were similar to the ambient snails. Snails (Pomacea scalaris, Sinotaia quadrata, Planorbioidae spp.), insects (Sphaerodema rustica, water scorpion),tadpole and fishes (Poecilia reticulate, Trichogaster trichopterus) were also found in the traps. Besides, two-opening traps with funnel entrance were more effective than the traps without funnel entrance. In general, in still water with ambient density of apple snails range from 6.2¡Ó 6.1 to 50.3¡Ó14.2 individual/m2,the relationship between attracted snails and ambient snail density was negative in chicken blood group (p < 0.001), positive in condensed fish soluble (p < 0.05) and no trend in banana group (p > 0.05). The results support the hypothesis that areas with abundant food usually have high snails density and those snails are less attracted by potential food items.

Thesis (M.S.)--Eastern Illinois University, 2009. / Includes bibliographical references (leaves 39-47).

Thesis (Ph.D.)--Tufts University, 2000. / Adviser: Sara M. Lewis. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 82-90). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (Ph.D.)--Tufts University, 2005. / Adviser: Sara M. Lewis. Submitted to the Dept. of Biology. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

No description available.

The anatomical source of the trail pheromone in the black carpenter ant, <I> Camponotus pennsylvanicus </I>, was investigated by presenting workers with crude or synthetic hindgut extracts to test for attractancy and trail-following behavior. Chemical analysis was used in conjunction with behavioral bioassays to detect and identify volatiles from the rectal sac, poison, and Dufour's glands. The rectal material was also examined to determine levels of total nitrogen and identify metabolites in relation to other solid material present. Under laboratory conditions, foragers demonstrated a significant level of attraction to a combined Dufour's gland, poison gland, and rectal sac extract. No response was observed to synthetic compounds (formic acid and saturated hydrocarbons) from the poison or Dufour's gland. Two volatiles, n-undecane and n-tridecane, were identified from the Dufour's gland. Fatty acids and esters were found to be ubiquitous in the Dufour's and poison glands. Palmitic acid was identified in the poison gland. A compound described as a component of the trail pheromone in <I> Camponotus atriceps </I> (3,4-dihydro-3,5-dihydroxy-6-methyl-pyran-4-one) was identified in the rectum, but was not verified behaviorally as being part of the trail pheromone for <I> C. pennsylvanicus </I>. Trail following was not elicited from any of the rectal sac extracts. Dry weight analysis determined that the rectal material was only 14% solid material and total nitrogen levels were estimated at 19.2 ± 2 ug/mg of ant feces. Most of the components contributing to the total nitrogen excreted were left unidentified, but ammonia (2.7 ± 1.2 ug/mg), two tryptophan intermediates (kynurenic and xanthurenic acid) and one pteridine (biopterin), were identified. / Master of Science

No description available.

No description available.

Platelet-derived growth factor D-chain (PDGF-D) is the newest member of the PDGF family of mitogens and chemo-attractants; it is expressed in a wide variety of cell types, including vascular smooth muscle cells (SMCs). The molecular mechanisms regulating PDGF-D transcription are unknown. Here I investigated the effects of angiotensin II (ATIl) and IL-1 beta on the transcription of PDGF-D and changes in vascular SMCs phenotype. Primer extension analysis mapped a single transcriptional start site to the ccAG CGC motif of PDGF-D promoter. Several potential transcription factor binding sites such as SpI, Ets-1, NF-??B, IRF-1, p53, Smad4 and AP1 were located in the proximal 1168bp of the PDGF-D promoter. ATII-inducible Ets-1 and PDGF-D gene expression is mediated via H202. IL-I beta supresses PDGF-D promoter activity, mRNA and protein expression in SMCs through NF-??B p65, IRF-1 and HDAC1, which form complex in the PDGF-D promoter. This study provides the first direct link between NF-KB and the PDGF-D promoter, IRF-1 with any member of the PDGF family and a new example of HDAC mediated inhibition of gene expression. In summary, this study investigates for the first time the mechanisms mediating the transcriptional regulation of PDGF-D in vascular SMCs. This provides valuable insights into the molecular control of vascular phenotype, and opens up potential opportunities for therapeutic intervention.

Thesis (Ph. D.)--University of Chicago, Dept. of Ecology and Evolution, March 2000. / Includes bibliographical references. Also available on the Internet.