The calculus of looping sequences is a formalism for describing the evolution of biological systems by means of term rewriting rules. We enrich this calculus with a type discipline to guarantee the soundness of reduction rules with respect to some biological properties deriving from the requirement of certain elements, and the repellency of others. As an example, we model a toy system where the...

pH-responsive surfaces, reversibly switching between superhydrophilicity and superhydrophobicity/water repellency, are developed by "grafting from" a pH-sensitive polymer onto a hierarchically micro/nano-structured substrate. We quantify the water repellency by investigating the restitution coefficient of water droplets bouncing off the surfaces. The water repellent state requires appropriate h...

Behavioral responses of two field populations of Anopheles minimus complex species A and C for contact and non-contact actions of chemicals were compared during and after exposure to operational field concentrations of DDT (2 g/m2), deltamethrin (0.02 g/m2), and lambdacyhalothrin (0.03 g/m2) using an excito-repellency escape chamber. The two populations were collected from the Mae Sot District ...

To confirm that Korean Food and Drug Administration (KFDA) guidelines are applicable to test the efficacy of mosquito repellents, these guidelines were used to test the efficacy and complete protection times (CPTs) of three representative mosquito repellents: N,N-diethyl-3-methylbenzamide (DEET), citronella, and fennel oil. The repellency of citronella oil decreased over time, from 97.9% at 0 h...

DEET is the most effective insect repellent available and has been widely used for more than half a century. Here, I review what is known about the olfactory and contact mechanisms of DEET repellency. For mosquitoes, DEET has at least two molecular targets: Odorant Receptors (ORs) mediate the effect of DEET at a distance, while unknown chemoreceptors mediate repellency upon contact. Additionall...

There is an increasing demand for air-dry performance of fluorocarbon finished materials. Thus, dyeing with different types of reactive, mono, bi, and multi-functional, dyes was evaluated as a novel treatment to create correct surface interface to maintain fluorocarbon performance without ironing or tumble drying. The effects of pre-treatment on fluorocarbon finishing of cotton fabric, a cellul...

Smoke from burning different kinds of vegetation or wood is often used as a cheap personal protection measure against mosquitos during the evening. To test the efficacy of smoke, a comparative field trial was conducted in the Wosera District, Papua New Guinea. Repellency of smoke from burning wild mango wood (Mangifera spp), leaves from betelnut (Areca catechu), wild ginger (Alpinia spp) and co...

Non-flouro copolymers containing a hydrophobic alkyl acrylate monomer (butyl acrylate/2-ethylhexyl acrylate/ lauryl acrylate) and a reactive monomer (maleic anhydride) have been synthesized using emulsion polymerization technique. The copolymer emulsions have been applied on to cotton fabric by a pad-dry-cure process and the water repellency of the fabrics before and after vigorous washes compa...

In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help a...

The methanol and ethyl acetate (EA) extracts of four species of sea lily (Himerometra magnipinna, Comaster multifidus, Comanthina sp., and Comatella maculata) were evaluated for their insecticidal activity against Yellow-fever mosquito larvae (Aedes aegypti) and their repellency against adult Asian Tiger mosquitoes (Aedes albopictus). The 24-hr minimum inhibition concentration (MIC) data reveal...