Background: Theory predicts strong bottom-up control in detritus-based food webs, yet field experiments with detritus-based terrestrial systems have uncovered contradictory evidence regarding the strength and pervasiveness of bottom-up control processes. Two factors likely leading to contradictory results are experiment duration, which influences exposure to temporal variation in abiotic factors such as rainfall and affects the likelihood of detecting approach to a new equilibrium; and openness of the experimental units to immigration and emigration. To investigate the contribution of these two factors, we conducted a long-term experiment with open and fenced plots in the forest that was the site of an earlier, short-term experiment (3.
View Article and Find Full Text PDFDengue, one of the most widespread infectious diseases, has affected U.S. military readiness throughout history.
View Article and Find Full Text PDFRecently, vector-borne diseases have been resurging in endemic areas and expanding their geographic range into nonendemic areas. Such changes have refocused attention to the potential for major public health events, as naive populations are exposed to these pathogens. Personal topical repellents, recommended by the United States Centers for Disease Control and Prevention and World Health Organization, remain a first line of protection against infection.
View Article and Find Full Text PDFTwo newly designed formulations of stick camouflage face paint, one with 30% N,N-diethyl-3-methylbenzamide (DEET) and the other without DEET, were evaluated for acceptability among soldiers upon completion of normal military field training exercises. A total of 156 soldiers participated and completed a self-administered survey answering questions about product acceptability, packaging, and ease of use. Results of the study indicated that soldiers found stick formulations, with and without DEET, to be acceptable for use (62.
View Article and Find Full Text PDFA combination of insect repellent, N,N-diethyl-3-methylbenzamide (deet), with camouflage face paint in a newly designed stick formulation was evaluated on human volunteers under field conditions in Belize during February 2007. The formulation provided over 90% protection against mosquitoes for 8 hours and at least 80% protection for 12 hours, with 100% protection for 2 to 4 hours after application.
View Article and Find Full Text PDFArthropod-borne diseases such as malaria, dengue, scrub typhus, and leishmaniasis continue to pose a significant threat to U.S. military forces deployed in support of operational and humanitarian missions.
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