The Alaska Volcano Observatory's lightning detection system detected and located 171 lightning strokes during the August 18, 1992, eruption of the Crater Peak vent of Mount Spurr volcano in Alaska. The strokes, predominantly intracloud, were detected during a 70-minute interval that began more than an hour into the eruption. All detected strokes were of positive polarity. The spatial distributi...

the distribution pattern of pest population is one of the factors not only effects on sampling program and data analysis method, but also can be used to measure the density of pests and their natural enemies. thus, the spatial distribution pattern of the pea aphid, acyrthosiphon pisum harris (hem.: aphididae) and its two major predators, hippodamia variegata goeze (col.: coccinellidae) and cocc...

the aim of this research was to investigate the effect of index species, astragalusammodendron on the associated plants of agropyron tauri and bromus tomentellus fromdifferent aspects in shazand rangeland in southwest of markazi province. the effects ofspecies density and distribution pattern and then index species on the soil properties werestudied. based on the randomized – systematic method,...

in order to determine the best form factor formula for loblolly pine (pinus taeda l.) plantations in talesh (western guilan province-iran), a number of 110 trees were selected based on their distribution in diameter classes, from 12 to 34 cm (in a two- cm diameter interval). first, several quantitative factors including diameter at breast height, diameter at 0.65 m of height, and diameter at st...

the effect of ph, different concentration of tween 80 and calcium ion on the stability of limonene-in-water emulsions stabilized by various concentration of sodium caseinate (2, 5 and 10%) was evaluated. to this end, emulsions were prepared by ultrasound and their quality attributes including size distribution, mean diameter of droplets, specific surface area and span number were studied as a r...

the two-spotted spider mite, tetranychus urticae koch (acari: tetranychidae), is an economically important pest of ornamental plant in iran. the population abundance and spatial distribution were studied on five rosa cultivars including maroussia, wendela, elderado, wenedetta, and hot lady during two growing seasons of 2011 and 2012 in greenhouse. the k parameter, index of dispersion, lloyd’s m...

Multifocal visual evoked potentials (VEP) allow one to assess whether stimulation at specific visual field locations elicits cortical activity; it might therefore enable us to conduct objective visual field perimetry. However, due to the cortical folding, which differs markedly between subjects, a particular electroencephalogram generator may fail to project signal on some recording electrodes....