the relationship between altitude, slope and tree age with the red heartwood of beech (fagusorientalis lipsky) were investigated. transect sampling method was used to collect the data. theresults showed that in the 476 sampled trees, 132 trees were suffering the phenomenon of red heartswith deferent shape and size. the results indicate that the tree with red heartwoods in shafa-roudforest area,...

Some Experimental Errors in Calculating Regional Cerebral Blood Flow From the Intracarotid Xe Clearance Curve • A digital model study has been developed for quantitative assessment of experimental errors in the analysis of Xe clearance curve from the brain. A small Computer synthesized a model of the clearance curve, varying combinations of fast and slow components. The curves were convoluted w...

We demonstrate for the first time an optically pumped gas laser based on population inversion using a hollow core photonic crystal fiber (HC-PCF). The HC-PCF filled with 12C2H2 gas is pumped with ~5 ns pulses at 1.52 μm and lases at 3.12 μm and 3.16 μm in the mid-infrared spectral region. The maximum measured laser pulse energy of ~6 nJ was obtained at a gas pressure of 7 torr with a fiber with...

the assumptions considered in developing the saint-venant equations limit their application in many practical situations. the modified boussinesq equation was presented to overcome the limitation imposed by saint-venant equation due to the presence of non-hydrostatic pressure distribution and steep slope. in this paper a computational model was developed for solving the modified and the traditi...

In 1992 Carlsen et al. reported a significant global decline in sperm density between 1938 and 1990 [Evidence for Decreasing Quality of Semen during Last 50 Years. Br Med J 305:609-613 (1992)]. We subsequently published a reanalysis of the studies included by Carlsen et al. [Swan et al. Have Sperm Densities Declined? A Reanalysis of Global Trend Data. Environ Health Perspect 105:1228-1232 (1997...

The present study examined F1 and F2 onset, as well as locus equations in Greek fricative – vowel sequences as distinctive cues for the fricative place of articulation. The effects of voicing, speaker’s gender and post-fricative vowel on both formants’ onset values and locus equations were also investigated. The results showed that F2 onset values distinguished fricatives in terms of place of a...

We investigate the promise of the Ly-α forest for high precision cosmology in the era of the Sloan Digital Sky Survey using low order N-point statistics. We show that with the existing data one can determine the amplitude, slope and curvature of the slope of the matter power spectrum with a few percent precision. Higher order statistics such as the bispectrum provide independent information tha...