Melanism is a common polymorphism in many insect species that also influences immune function. According to the thermal melanin hypothesis, ectothermic individuals from cooler environments have darker cuticles and higher polyphenol oxidase (PO) levels, which represent a better immunocompetence. In this study, the links among environmental temperature, melanism, and PO activity of Saccharosydne ...

A scanning phosphorescence quenching microscopy technique, designed to prevent accumulated O(2) consumption by the method, was applied to Po(2) measurements in mesenteric tissue. In an attempt to further increase the accuracy of the measurements, albumin-bound probe was topically applied to the tissue and an objective-mounted pressurized bag was used to reduce the oxygen transport bypass throug...

The present study was carried out to investigate the effect of entomopathogenic fungus, Beauveria bassiana on immune response mediated Phenoloxidase enzyme of Spodoptera litura larvae. To measure the PO enzyme activity, haemolymph of 3rd, 4th and 5th instar larvae of S. litura were treated with different doses of 1.0×108, 2.0×107, 4.0×106 and 8.5×105 spores/ml of B. bassiana. The results indica...

The use of flash photolysis of caged Ca 2 1 to rapidly elevate [Ca 2 1 ] at the cytosolic face of a cardiac ryanodine receptor (RyR) channel reconstituted into a bilayer gives rise to a rapid increase in open probability (Po; Györke and Fill, 1993). This is followed by a decline in Po, which occurs much more slowly ( t 5 1.3 s). After the decline in Po, the channels can be reactivated by a seco...

It remains uncertain whether the delayed onset of mitochondrial respiration on initiation of muscle contractions is related to O(2) availability. The purpose of this research was to measure the kinetics of the fall in intracellular PO(2) at the onset of a contractile work period in rested and previously worked single skeletal muscle fibers. Intact single skeletal muscle fibers (n = 11) from Xen...

The extreme anoxia-tolerance of freshwater turtles under cold conditions is well documented, but little is known about their cardiac performance in such situations. Using chronic catheterization techniques, we measured systemic cardiac power output (PO(sys)), systemic cardiac output (Q(.)(sys)), heart rate (fh), systemic stroke volume (V(s,sys)), systemic resistance (R(sys)) and mean arterial p...

We show that there exist Po > 0 ar>d P\, ■■■ , Pn nonnegative integers, such that 0 < p(x) = Po + Pi cosx + • ■ • + Pn cos Nx and po -C s1/3 for .s = J2'J=oPj < improving on a result of Odlyzko who showed the existence of such a polynomial p that satisfies Po < (.slogs)1/3 . Our result implies an improvement of the best known estimate for a problem of Erdos and Szekeres. As our method is noncon...

Let $S$ be a dense subsemigroup of $(0,+infty)$. In this paper, we state   definition of thick near zero, and also  we will introduce a definition that is equivalent to the definition of piecewise syndetic near zero which presented by Hindman  and Leader in [6].  We define density near zero for subsets of $S$ by a collection of nonempty finite subsets of $S$ and we investigate the conditions un...