Intraexciton transitions in semiconductor quantum wells are modulated by strong and tunable few-cycle terahertz pulses. Time-resolved terahertz-pump and optical-probe measurements demonstrate that the 1s heavy-hole and light-hole exciton resonances undergo large-amplitude spectral modulations when the terahertz radiation is tuned near the 1s–2p intraexciton transition. The strong nonlinear optical transients exhibit...
Measurements on growth traits up to 41 years of age
from 68 progeny sites in eight first-generation breeding
zones of coastal Douglas-fir (Pseudotsuga menziesii
[MIRB.] FRANCO var. menziesii) in the US Pacific Northwest
were used to investigate age trends of genetic parameters
and to determine optimum age of selection. Heritabilities...
The end of the Cold War brought about changes within international political relations that resulted in expanded interest in global civil society. Such developments, like globalization and democratization, have encouraged the growth of social and political organizations. Political scientists have found that these inter-governmental and non-governmental organizations have a significant...
Recalcitrance to transformation makes genetic engineering of many valuable plants infeasible for practical use. Transitory host modification during transformation using transgenes offers a possible means of overcoming this obstacle. In prior work in our laboratory, the genes GA20ox7 and EBB1 were found to increase regeneration in vitro. In this project,...
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Model poplar hybrid Populus tremula x P. alba (clone INRA 717-1B4)
Recalcitrant Populus trichocarpa (N-1
In shallow water, any two waves of the same frequency are shown to produce complex patterns of
drift velocity above the sea bed. If the longshore components λ₁, λ₂ of the wave numbers of the two
waves are different, these steady flow patterns exhibit a longshore periodicity of wave number...