Ingunn Ulrich and Wolfgang Ulrich Institut für Genetik. Universität Hohenheim , Garbenstraße 30, D-7000 Stuttgart-Hohenheim , Bundesrepublik Deutschland Z. Naturforsch. 41c, 1052 — 1056 (1986); received July 23, 1986 Flow Cytometry, Plant Protoplasts, Protoplasts Preparation, D N A , D A PI Protoplasts prepared from leaves of various higher plants were stained with the specific DNA fluorochrome...

We have screened a panel of tetracycline (tc)-like compounds for their potential use with tc-repressor (tetR) based gene switches. The interaction between tc and tetR appears quite specific, as only tc itself and its close homologues anhydro-tc and doxycycline strongly inhibited DNA binding. However, a single tc-like compound, GR33076X, increased DNA binding of the tetR-VP16 fusion protein, bot...

In recent years, the rationalization of concrete mix ratios which batches equal volumes sand and gravel in building projects has been gaining grounds Cameroon construction industry. The main objective this study is therefore to investigate if produced with rationalized ratio can be adopted as conventional terms minimum required compression strength for buildings. Specifically work compared 350 ...

Organisms with external fertilization are often sperm limited, and in echinoids, larger eggs have a higher probability of fertilization than smaller eggs. This difference is thought to be a result of the more frequent sperm-egg collisions experienced by larger targets. Here we report how two components of egg target size, the egg cell and jelly coat, contributed to fertilization success in a se...

The massive dune sea of the southern Namib Desert is approximately 800 km in length and some 140 km wide. These dunes are among the highest in the world and, in spite of very sparse vegetation cover, they support a surprising variety of reptiles and arthropods (Koch, 1961; Louw & Seely, 1982). A feature of the arthropod fauna is the high species diversity of flightless tenebrionid beetles. Thes...

Complex life cycles have evolved independently numerous times in marine animals as well as in disparate algae. Such life histories typically involve a dispersive immature stage followed by settlement and metamorphosis to an adult stage on the sea floor. One commonality among animals exhibiting transitions of this type is that their larvae pass through a 'precompetent' period in which they do no...

Abstract The major drawbacks of a railway track include noise, vibration, and aggravated degradation. Resilient mats asphalt have been increasingly used in recent years to mitigate this noise vibration. However, these materials are quite expensive. Conventional is very stiff brittle, making it more prone cracking. present work aims develop novel material that can be as base layer ballasted slab...