The widely used insect repellent DEET has a limited spatial zone of protection, requiring it to be applied over all exposed areas of skin. Identification of insect DEET-sensing neurons expressing a highly conserved Ionotropic receptor, Ir40a, provides an opportunity to identify new structural classes of volatile agonists as potential spatial repellents. By imaging the activity of the Ir40a+ neu...

The knock-down, mortality and 'irritancy' effects of three synthetic repellents (DEET, IR3535 and KBR 3023) on Aedes aegypti (L) (Diptera: Culicidae) were evaluated in the laboratory in the absence of animal bait. Filter paper tests were carried out to assess the knock-down effect (KDt(50) and KDt(95)) and mortality (LC(50) and LC(95)) induced by each repellent. 'Irritancy' tests were carried o...

The repellents N,N-diethyl-3-methylbenzamide (deet) and racemic 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (AI3-37220) were evaluated using two different laboratory bioassays to determine their relative effectiveness against host-seeking nymphs of the blacklegged tick, Ixodes scapularis Say, and the lone star tick, Amblyomma americanum (L.). In a petri dish bioassay, ticks were released wi...

The paper deals with the aqueous environmental fate of N,N-diethyl-m-toluamide (DEET), one of the most widespread and efficient mosquito repellents. The investigation involved monitoring of the DEET decomposition and the identification of intermediate compounds. Initially, control experiments in the dark and under illumination were performed on sterilized and river water spiked with DEET, with ...

Background. The worldwide threat of arthropod transmitted diseased, with their associated morbidity and mortality, underscores the need for effective insect repellents. Multiple chemical, botanical, and “alternative” repellent products are marketed to consumers. We sought to determine which products available in the United States provide reliable and prolonged complete protection from mosquito ...

Although infants perceptually attune to native vowels and consonants well before 12 months, at 13-15 months, they have difficulty learning to associate novel words that differ by their initial consonant (e.g., BIN and DIN) to their visual referents. However, this difficulty may not apply to all minimal pair novel words. While Canadian English (CE) 15-month-olds failed to respond to a switch fro...

BACKGROUND The worldwide threat of arthropod-transmitted diseases, with their associated morbidity and mortality, underscores the need for effective insect repellents. Multiple chemical, botanical, and "alternative" repellent products are marketed to consumers. We sought to determine which products available in the United States provide reliable and prolonged complete protection from mosquito b...

The repellent efficacy of 15% N,N-diethyl-3-methylbenzamide (DEET), 0.6% citronella oil, and 0.3% alpha-cyano-cypermethrin against Culicoides species was compared in three 5x5 Latin squares (15 replicates) under South African field conditions. DEET, citronella oil or alpha-cyano-cypermethrin were applied to polyester meshes that were fitted to down-draught suction 220V UV light traps which were...

Responses of host-seeking nymphs of the blacklegged tick, Ixodes scapularis Say and lone star tick, Amblyomma americanum (Linnaeus) (Acari: Ixodidae) to the repellents N,N-diethyl-3-methylbenzamide (deet) and (1S, 2'S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide (SS220) were studied using fingertip laboratory bioassays. Ethanol solutions of both compounds applied to the skin strongly repell...

Pseudomonas putida DTB grew aerobically with N,N-diethyl-m-toluamide (DEET) as a sole carbon source, initially breaking it down into 3-methylbenzoate and diethylamine. The former was further metabolized via 3-methylcatechol and meta ring cleavage. A gene from DTB, dthA, was heterologously expressed and shown to encode the ability to hydrolyze DEET into 3-methylbenzoate and diethylamine.