The anomalous-diffraction theory (ADT) of extinction of light by soft particles is shown to be determined by a statistical distribution of the geometrical paths of individual rays inside the particles. Light extinction depends on the mean and the mean-squared geometrical paths of the rays. Analytical formulas for optical efficiencies from a Gaussian distribution of the geometrical paths of rays...

Extinction of classical conditioning is thought to produce new learning that masks or interferes with the original memory. However, research in the nudibranch Hermissenda crassicornis (H.c.) has challenged this view, and instead suggested that extinction erased the original associative memory. We have re-examined extinction in H.c. to test whether extinguished associative memories can be detect...

The experimental was split plot in a randomized complete block design with three replications. In this experiment, different levels of nitrogen in the main plots included four levels (0, 50, 100 and 150 N) kg.ha-1 urea and wheat varieties, including cultivars, Sepahan and SW were placed in the subplots. Results showed that nitrogen fertilizer and cultivar were significant effects on ...

the experimental was split plot in a randomized complete block design with three replications. in this experiment, different levels of nitrogen in the main plots included four levels (0, 50, 100 and 150 n) kg.ha-1 urea and wheat varieties, including cultivars, sepahan and sw were placed in the subplots. results showed that nitrogen fertilizer and cultivar were significant effects on maximum lig...

We present extinction spectra of sodium nitroprusside exhibiting holographic light scattering after irradiation with coherent light. A characteristic extinction band appearing in the vicinity of the wavelength of the pump beam was discovered as well as an increase of the extinction coefficient over the whole spectral range. These features are proved to originate from diffraction of the probe be...

extinction coefficient (k) is an important index that shows the rate of light decrease in canopy. net biomass accumulation is linearly related to cummulative light interception. the slope of this relationship is termed radiation use efficiency. a split plot experiment within randomized complete block design with three replications was conducted in april 2001 in sugar beet research station in ka...

Previous research has shown that an acute, post-training injection of D-cycloserine (DCS) facilitates extinction of conditioned fear in rats; however, the effects of multiple exposures to DCS in this situation are not known. In Experiment 1, rats were conditioned (light-shock pairings) and 24 h later given six extinction (light-alone) trials followed by an injection of DCS (15 mg/kg) or saline....

The functional properties of the light adaptation system in the superposition eye of the moth Agrotis segetum have been investigated by reflection spectroscopy. The spectrum of the reflected light from the tapetum of dark adapted eyes had a peak at about 580 nm corresponding to a spacing between the reflecting layers in the tapetum of 145 nm. During light adaptation of the eye the observed refl...

the aim of this research was to compare more and less competitiveness of rice cultivars against barnyardgrass for light extinction coefficient and canopy structur. a filed experiment was conducted in 2007 growing season in tonekabon’s rice research station in mazandaran province. the experiment layout was a factorial design with four randomized complete blocks. seven rice cultivars (khazar, sep...

Light extinction by aerosols is due to scattering and absorption. The anthropogenic contribution is generally dominated by light scattering by sulfate particles and light absorption by elemental carbon. While real-time, in situ instrumentation for the measurement of ambient light scattering exists and is widely used (i.e., nephelometers), no such instrumentation is currently in use for the sens...