Identifying factors that influence variation in light availability within forested ecosystems represents an important component in our understanding of the complex determinants of tree seedling regeneration. We assessed the influence of forest structure and canopy tree architecture on spatial heterogeneity of understory light availability in three old-growth and three second-growth forests in l...

The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water (Psi(L)) and osmotic (Psi(pi)) potential, bulk tissue yield threshold and final ...

air pollution is one of the most challengeable problems in the asalouyeh zone. in order to reduce the air pollutants emission and their effects it is necessary to recognize the amount and spatial dispersion of air pollutants. hence in this paper, evaporative losses of the stored liquids from 16 tanks of an oil company in asalouyeh zone, are determined using tanks 4.0.9d and then dispersion of v...

background: peak expiratory flow rate (pefr) is recommended as a tool for control of asthma. the purpose of this study was to determine the normal value of pefr in the healthy high school children in babol, iran. methods: this study was conducted on 470 healthy high school children (285 girls, 185 boys with the age between 14-18 years). for the determination of pefr we used mini wright peak flo...

For M an R-module and m an element of M we define the order ideal, 0M(m), to be the ideal which consists of the images of m under homomorphisms of M to R. The proof proceeds by considering the height of particular order ideals, 0M(m), in relation to the projective dimension of M. Specifically, if M is a kth syzygy of the 7?-module TV and if xx, . . . ,xk_l is an R sequence, then Torf (TV, R/(xi...

objectives: the goal of the present study was to compare the role of vision on static postural stability between athletes and nonathletes. methods: participants included two groups of 25 persons, men karatekas who were selected in isfahan (age 20.6±2.8 years, 66.24±10.34 kg of weight, height 1.76±0.07 m) and healthy young men in isfahan (age 21.6±2.33 years, 66.8±11.34 kg of weight, height 1.74...

to evaluate the role of effective factors on competition of two wheat cultivars against two species of narrow leaf and broad leaf weeds this study was conducted as two separated experiments based on a randomized complete block design with 3 replications at agricultural faculty of bu-ali sina university, in 2008-2009. in both experiments, alvand and sayson cultivars were planted with densities o...

Pelletizing plant of the Gol-E-Gohar mining and industrial company consists of a burner, a dry ball mill (6.2 m × 13 m), and an air separator. The ball mill consists of a 2 m-long drying and an 11 m-long grinding chambers. The iron ore concentrate is fed to the drying chamber by a feed chute. It was found that when the feed moisture content increased from 1.3% to 3.5%, the throughput decreased ...

mapping the QTLs of agronomic and physiological traits, 149 double haploid (DH) lines from a cross between an Australian cultivar, Clipper (salt susceptible), and an Algerian landrace, Sahara3771 (salt tolerant), were evaluated under natural saline (Yazd Station, ECsoil=10-12.8 ds/m and ECwater= 9-10 ds/m) and normal (Karaj Station, ECsoil and ECwater ~2-2.5 ds/m) environments. There were remar...