Publish in OALib Journal
APC: Only $99
Observations and numeric modeling of internal wave
generation and transformation in the
shelf zone of sea show that the main part of tidal energy is transported to
shores in form of internal gravitational waves. Long-term measurements of
temperature and current velocity fluctuations at many levels in the near-bottom
thermocline were carried out during the periods when stable seasonal
thermocline was present. Analysis of the measurements permits us to understand
mechanisms of internal wave destruction with turbulent motion generation and
corresponding rebuilding of velocity and density mean fields in the stratified
near-bottom layer. Spectral analysis of temperature fluctuations shows that in
shoaling internal waves the low-frequency maxima disappear, maxima at higher frequencies
appear, and the spectra slope in the high frequency range changes with depth.
Taking into account the concurrent analysis of near-bottom pressure
fluctuations and current velocity fluctuations from surface till bottom we come
to the conclusion that breaking internal waves in a near-bottom thermocline
generate not only small-scale three-dimensional turbulence, but also quasi-horizontal
turbulence of larger scales, which considerably contributes into mixing and
sediments, alluvium, and nutrients transport in the shelf zone of sea.
The present work
gives a detailed study of in vitro shoot organogenesis of the ornamental onion A.
altissimum Regel from the buds of the middle layer of the inflorescences.
The course of morphogenesis was examined by light and scanning electron
microscopy. Histological observation revealed that during 3 - 5 days of culture
on the BDS medium supplemented with 2.0 mg·L-1 of
BA and 2.0 mg·L-1 of NAA the
epidermal cells of the stamen filament in the area of its fusion with the tepal
became competent and dedifferentiated. Originally the organogenesis involved
several initial epidermal cells. The formation of meristematic centers was
observed from day 3 to day 14. The apical shoot meristems and leaf primordia in
a roller shape formed from day 14 to day 28 of culture on the same media. The
further development of vegetative shoots and formation of the bulblets were
observed when the explants were stimulated by triapenthenol (2.0 mg·L-1).