IN comparative studies of the mutagenic action of ionizing and ultraviolet radiation on conidia of the fungus Glomerella (5) it was evident that the shape of the mutation curve was different for the two types of radiation. The dose-mutation curve for the surviving spores was essentially linear for the ionizing radiations, but with the ultraviolet radiation the mutation curve rose with increasin...

While the exponential learning equation, indicating a gradually diminishing improvement, is one of the standard equations to describe learning, a sigmoid behavior with initially increasing then decreasing improvement has also been suggested. Herewe show that the sigmoid behavior ismathematically derived from the standard exponential equation when the independent variable of the equation is rest...

Although venous capacitance has been studied in the neurally isolated tissue or in the in vitro vein segment, this is the first study of sympathetic regulation of the pressure-diameter relation in mesenteric veins in situ, where innervation is kept intact. In 25 alpha-chloralose-anesthetized rabbits, mesenteric vein diameter (679 +/- 27 microns, ranges of 380-1,050 microns at initial state) and...

Article history: Received 9 July 2007 Received in revised form 2 January 2008 Accepted 10 January 2008 Ecotones are zones of transition between two adjacent ecological systems and are characterized by a high rate of change compared to these adjacent areas. They are dynamic entities with both a spatial and temporal property, reflected in an ecotone width and location, which vary across time duri...

This paper proposes a tone-reproduction method that uses a neural network and modified sigmoid function to perceptually compensate the characteristics of an output device. An inkjet printer was used as the output device the characteristics of which were analyzed by colorimetric measurement. The measured device-characteristic data for primary inks were then used to model the I/O characteristics ...

The study pertains to the estimation of carcass traits of broiler duck reared in hot and humid climate of Eastern India. The carcass and different cut weights were estimated using non invasive measurements, breast angle and body weights separately at different ages, i.e. 21, 28,35,42,49 and 56 days of age. The carcass traits were estimated using linear, logarithmic, exponential, inverse, power,...

Let data of a univariate process be given. If the data are related by a sigmoid curve, but the sigmoid property has been lost due to the errors of the measuring process, then the least sum of squares change to the data that provides nonnegative third divided differences may be required. It is a structured quadratic programming calculation, which is solved very efficiently by a special least squ...