Release of volatiles in oil emulsion systems containing various fat contents was determined using purge-and-trap dynamic headspace/gas chromatography. Oil emulsions were prepared using 0, 0.5, 1, 2, 4, or 8% oil, and a standard mixture was prepared using hydrocarbons, aldehydes, ketones, and alcohols. Fat content in oil emulsions reduced the volatility of added volatile standards, and the amoun...

Major volatiles from young and mature leaves of different citrus types were analyzed by headspace-solid phase microextraction (HS-SPME)-GC-MS. A total of 123 components were identified form nine citrus cultivars, including nine aldehydes, 19 monoterpene hydrocarbons, 27 oxygenated monoterpenes, 43 sesquiterpene hydrocarbons, eight oxygenated sesquiterpenes, two ketones, six esters and nine misc...

The effects of insect larval diet on adult olfactory responses to host-plant or food volatiles are still debated. The induction of adult host preferences has been studied in insects with diverse ecologies, including parasitoids, flower-visitors and phytophagous species. We investigated this question for the first time in a coprophagous insect species. Larvae of the French scarab dung beetle Agr...

[1] We have modeled the nucleation and isothermal growth of bubbles in dacite from the 1912 Plinian eruption of Novarupta, Alaska. Bubble growth calculations account for the exsolution of H2O and CO2, beginning with bubble nucleation and ending when bubble sizes reproduced the observed size distribution of vesicles in Novarupta pumice clasts. Assuming classical nucleation theory, bubbles nuclea...

12 The contribution of low-abundance microbial species to soil ecosystems is easily overlooked 13 because there is considerable overlap between metabolic abilities (functional redundancy) of 14 dominant and subordinate microbial species. Here we studied how loss of less abundant soil 15 bacteria affected the production of antifungal volatiles, an important factor in the natural control 16 of so...

Herbivory is a key innovation in insects, yet has only evolved in one-third of living orders. The evolution of herbivory likely involves major behavioral changes mediated by remodeling of canonical chemosensory modules. Herbivorous flies in the genus Scaptomyza (Drosophilidae) are compelling species in which to study the genomic architecture linked to the transition to herbivory because they re...

The ability of humans to distinguish the delicate differences in food flavors depends mostly on retronasal smell, in which food volatiles entrained into the airway at the back of the oral cavity are transported by exhaled air through the nasal cavity to stimulate the olfactory receptor neurons. Little is known whether food volatiles are preferentially carried by retronasal flow toward the nasal...

Compared to Earth’s atmosphere, Mars has a thin CO2-rich atmosphere with a surface pressure of about 700 Pa. When normalized to planetary mass (mass of Mars is 10.7% of that of Earth), the abundance of volatiles on Mars is about 0.07% to 6% of that on Earth (when CO2 in terrestrial carbonates is included). Is the depletion of volatiles on Mars a primary feature (because less volatiles accreted ...

Plant volatiles induced by herbivory are often used as olfactory cues by foraging herbivores and their natural enemies, and thus have potential for control of agricultural pests. Compared to chewing insects and mites, little is known about plant volatile production following herbivory by insects with piercing-sucking mouthparts. Here, we studied factors (insect life stage, gender, the role of s...

Attack of plants by herbivorous arthropods may result in considerable changes to the plant's chemical phenotype with respect to emission of herbivore-induced plant volatiles (HIPVs). These HIPVs have been shown to act as repellents to the attacking insects as well as attractants for the insects antagonistic to these herbivores. Plants can also respond to HIPV signals from other plants that warn...