a faunistic list of syrphidae sampled in the agroecosystems of neyshabur (khorasan-razavi province) through malaise, yellow water traps and hand net is hereby presented for the first time. a total of 22 species were collected, including 13 species through malaise trap, 5 through yellow water trap as well as representatives of all species sampled through hand net. among the species collected, 8 ...

The phenomenon of transvection is well known for the Drosophila yellow locus. Thus enhancers of a promoterless yellow locus in one homologous chromosome can activate the yellow promoter in the other chromosome where the enhancers are inactive or deleted. In this report, we examined the requirements for trans-activation of the yellow promoter at the end of the deficient chromosome. A number of t...

the electrocoagulation (ec) is a simple and efficient method for the treatment of many water and wastewaters.the kinetics of decolorization of acid yellow 23 by ec using iron electrodes was studied. theelectrodecolorization rate follows pseudo-first order kinetic with respect to the ay23 concentration havingkapp= 5.65 cm min-1 at t= 295 k. the rate equation is as follows:ln [ay23]t – ln [ay23]0...

The US Army Yellow Fever Board was established to discover the etiology of yellow fever. In Cuba in 1900, the Board completed a series of classic experiments that showed the role of the mosquito in yellow fever transmission. Attending Private John Kissinger, who volunteered to be infected with yellow fever, are (from left) Major William C. Gorgas, the sanitation officer for Havana who would go ...

Evening: Yellow Ointment (Ung. Hydrarg. Oxid. Flav. 2 per cent.) 2nd day, morning: Yellow Ointment. Evening: Yellow ointment. 3rd day, morning: Yellow Ointment. Evening: Zinc Sulph. and Ichthyol Ointment (\ per cent. each). 4th day, Operation. If there is discharge, we continue the yellow ointment until it ceases and the eye is fit for operation. Usually after three or four days, the eye is fre...

Flower visiting Eristalis hoverflies feed on nectar and pollen and are known to rely on innate colour preferences. In addition to a preference for visiting yellow flowers, the flies possess an innate proboscis reflex elicited by chemical as well as yellow colour stimuli. In this study we show that the flies' proboscis reflex is only triggered by yellow colour stimuli and not altered by conditio...

Most flowers display distinct colour patterns comprising two different areas. The peripheral large-area component of floral colour patterns attracts flower visitors from some distance and the central small-area component guides flower visitors towards landing sites. Whereas the peripheral colour is largely variable among species, the central colour, produced mostly by anthers and pollen or poll...

Understanding the mechanism(s) that favour cooperation among individuals competing for the same resources provides direct insights into the evolution of grouping behaviour. In a hybrid zone between golden-/yellow-collared (Manacus vitellinus) and white-collared (Manacus candei) manakins, males form aggregations composed of white and yellow males solely to attract females ('mixed leks'). Previou...