Behavioral and electrophysiological tests were performed to evaluate the responses of workers of the ant Solenopsis geminata (Fabricius) from different size categories to Dufour gland extracts. Morphometric measures based in head widths across eyes were used to determine worker sizes. Trail following response of different worker sizes to Dufour gland extract from workers of different sizes was ...

Linear stability of double diffusive convection of Darcy-Maxwell fluid with Soret and Dufour effects is investigated. The effects of the Soret and Dufour numbers, Lewis number, relaxation time and solutal Darcy Rayleigh number on the stationary and oscillatory convection are presented graphically. The Dufour number enhances the stability of Darcy-Maxwell fluid for stationary convection while it...

A search for the products of fusion reactions that could be triggered by sparking in hydrogen isotopes was carried out. No signatures above background were found. On the contrary, the excess energy production was confirmed in the simple hydrogen/palladium system. The formation of a tightly bound state of the hydrogen (deuterium) atom is hypothesized to explain these results.

The venom apparatus of four hymenopterous parasitoids, including two bethylids, C. tarsalis (Ashmead) and C. waterstoni (Gahan), and two pteromalids, A. calandrae (Howard) and P. cerealellae (Ashmead), were removed and the associated Dufour glands characterized with respect to their external morphology and chemistry. Dufour glands in all four species have a characteristic translucent appearance...

In this paper, mixed convection flow of couple stress fluid in circular annulus is studied. First order chemical reaction, Soret and Dufour effects are taken into consideration. The governing partial differential equations are transformed into a system of ordinary differential equations and solved by Homotopy Analysis Method (HAM). The effects of Soret number, Dufour number, chemical reaction p...

Minor workers of the ant Zacryptocerus pusillus have unusual exocrine secretions in both their mandibular and Dufour glands. The mandibular glands contain a 3:1 mixture of 4-heptanone and 4-heptanol, a mixture found only in the related species Z. varians. The Dufour gland contains a mixture of 13 aldehydes from C9 to C18, not previously encountered in ant secretions. The venom glands gave varia...

Several North American species of Pogonomyrmex harvester ants exhibit group foraging, whereas South American species are exclusively solitary foragers. The composition of the secretions of the poison and Dufour glands in the South American species, Pogonomyrmex vermiculatus, were analyzed, and the secretions and their components were tested as trail pheromones in laboratory bioassays. The major...

The present study considers the numerical examination of an unsteady thermo-solutal mixed convection when the extra mass and heat diffusions, called as Soret and Dufour effects, were not neglected. The numerical simulations were performed in a lid-driven cavity, where the horizontal walls were kept in constant temperatures and concentrations. The vertical walls were well insulated. A finite vol...

First space-borne measurements of methanol inside aged tropical biomass burning plumes using the ACE-FTS instrument G. Dufour, C. D. Boone, C. P. Rinsland, and P. F. Bernath Laboratoire de Météorologie Dynamique/Institut Pierre Simon Laplace, Palaiseau, France Department of Chemistry, University of Waterloo, Ontario, Canada NASA Langley Research Center, Hampton, VA, USA Received: 25 January 200...

-Dufour glands of minor workers of Camponotus aegyptiacus contain a mixture of linear and methyl branched hydrocarbons and a trace of dodecyl acetate. Major workers contain a similar mixture of hydrocarbons but also large quantities of dodecyl acetate, some other long chain acetates and traces of propionates and farnesyl acetate. Cataglyphis savignyi has pentadecane as the most abundant compoun...