This study aims to develop eco-friendly botanical pesticides. Dried fruits of star anise (Illicium verum Hook.f. (Austrobaileyales: Schisandraceae)) were extracted with methyl alcohol (MA), ethyl acetate (EA), and petroleum ether (PE) at 25°C. The constituents were determined by gas chromatography-mass spectrometry, and the repellency and contact toxicity of the extracts against Sitophilus zeam...

This study was developed to evaluate the repellent activity of N,N-diethyl-3-methylbenzamide (DEET) against Amblyomma cajennense nymphs. Two repellent bioassays were compared and the effective concentration and repellent time were calculated. The fingertip test was accomplished to evaluate in vivo four concentrations of the compound (0.200; 0.100; 0.050 and 0.025 mg.cm⁻²) and the filter-paper b...

Improving water repellency of a metal surface is required in a wide range of industrial applications. In this study, the water repellency control of an oxygenfree copper surface was attempted by generating micro V grooves on the surface by using ultraprecision cutting technology. The results showed that the maximum contact angle of a water drop on a micro Vgrooved surface could be as high as ap...

A study was conducted to compare responses of male and female Aedes aegypti (Linn.) and Aedes taeniorhynchus (Wiedemann) to 9 olfactory repellents in the World Health Organization insecticide irritability test system. An irritant insecticide (permethrin) and a control were included for comparison. Aedes aegypti exhibited significantly more takeoffs than Ae. taeniorhynchus, and female mosquitoes...

Although widely used, the term repellency needs to be employed with care when applied to ticks and other periodic or permanent ectoparasites. Repellency has classically been used to describe the effects of a substance that causes a flying arthropod to make oriented movements away from its source. However, for crawling arthropods such as ticks, the term commonly subsumes a range of effects that ...

New alternative insecticides are necessary for the chemical control of head lice. In this study the fumigant knockdown time 50% (KT50) and repellency index (RI) of three aliphatic lactones was compared with two essential oils and DDVP, against permethrin-resistance Pediculus humanus capitis from Argentina. In the fumigant assay, none of the lactones were effective compared to the highest activi...

Six controlled-release personal-use topical insect/arthropod repellent formulations of diethylmethylbenzamide (deet) were evaluated in an environmental chamber on volunteers for repellency against the mosquitoes Aedes aegypti and Ae. taeniorhynchus under three climatic regimens: basic variable high humidity (tropical environment), basic constant high humidity (forested and wet environment) and ...

Environmental concerns related to perfluoroctanoic acid (PFOA) led to a re-examination of the methods for imparting stain resistance and stain repellency to textiles. Non-PFOA fluoropolymer finishes have been formed on cotton knits by admicellar polymerization, a surface analogue of emulsion polymerization. Fabric samples were characterized by a drop test, contact angle measurements, SEM, eleme...

Five individual bioassay repellency or toxicity variables were estimated or determined for deer.mice (Peromyscus maniculatus) and house mice (Mus musculus) under laboratory conditions. ALD's (Approximate Lethal Doses) or LDs0's of 230 chemicals to deer mice are presented, as are food reduction (FR) values (3-day feeding test as a 2.0% treatment rate) for white wheat seeds (Triticum aestivum) fo...

An important element of evaluating a large wildfire is to assess its effects on the soil in order to predict the potential watershed response. After the 55 000 ha Hayman Fire on the Colorado Front Range, 24 soil and vegetation variables were measured to determine the key variables that could be used for a rapid field assessment of burn severity. The percentage of exposed mineral soil and litter...