scape bending disorder is the most important factor affecting postharvest loss of gerbera cut flowers. one of the ultimate reasons for gerbera stem bending is lignin, with deformation structural functions and defensive mechanisms. this postharvest experiment was conducted to evaluate the role of phenylalanine ammonia lyase (pal) and peroxidase (pod) enzymes activity in stem bending of two gerbe...

The paper analyses biometrical and anatomical traits of wood in a leaning stem of pine trees. For study purpose, five pine trees (Pinus sylvestris L.) with a visibly leaning stem were chosen. Wood samples were taken at three different stem heights, that is, below the stem curvature, at the curvature and above the curvature. Microscopic specimens were prepared and used for the following measurem...

Phototropic response in etiolated pea (Pisum sativum L. cv Alaska) seedlings is poor. However, the curvature induced by unilateral blue light can be hastened and increased in magnitude by a previously administered red light pulse followed by several hours of darkness. Phytochrome is involved in the red light effect. Phototropic response was almost completely inhibited by removal of the apical b...

in this paper, the time-like hyperruled surfaces in the minkowski 4-space and their algebraicinvariants are worked. also some characteristic results are found about these algebraic invariants.

The putative Ca(2+)-channel blocker LaCl3 prevented the gravitropic bending of cut snapdragon (Antirrhinum majus L.) spikes (S. Philosoph-Hadas, S. Meir, I. Rosenberger, A.H. Halevy [1996] Plant Physiol 110: 301-310) and inhibited stem curvature to a greater extent than vertical and horizontal stem elongation at the bending zone. This might indicate that LaCl3, which modulates cytosolic Ca2+, d...

‎let $m^n$ be an $n(ngeq 3)$-dimensional complete connected and‎ ‎oriented spacelike hypersurface in a de sitter space or an anti-de‎ ‎sitter space‎, ‎$s$ and $k$ be the squared norm of the second‎ ‎fundamental form and gauss-kronecker curvature of $m^n$‎. ‎if $s$ or‎ ‎$k$ is constant‎, ‎nonzero and $m^n$ has two distinct principal‎ ‎curvatures one of which is simple‎, ‎we obtain some‎ ‎charact...

The curvature of the helical trajectory formed by herbaceous stem-twiners has been hypothesized to be constant on uniformly sized cylindrical supports and remains constant on different supports varying in diameter. However, experimental studies on the constant curvature hypothesis have been very limited. Here, we tested the hypothesis in a series of experiments on five herbaceous stem-twiners (...

Using the visual search method, we show that stimuli that contain curvature discontinuities (i.e., points where the second derivative along an image contour is not defined) are easily found among stimuli containing only smooth changes in curvature. Curved stimuli that lack curvature discontinuities, however, are difficult to find among distractors that have them. These results suggest that the ...