In this report, we describe a mitotic analysis (Giemsa technique) of six species of the genus Vernonia sensu Baker (Asteraceae, Vernonieae, section Lepidaploa) in order to assess the validity of maintaining this genus (sensu Baker) or dividing it into several lesser genera (sensu Robinson). Specimens of the seven species were collected in “cerrado” and “campo rupestre” areas in the states of Sã...

The subject handled in this study is the determination of antioxidant activities of extracts obtained from the Urginea maritima (L.) Baker plant’s leaves and tubers. Extractions which were obtained using various solvents as methanol, ethanol, acetone and benzine. The antioxidant activity of the extracts was determined using β-karotene-linoleic acid system. Moreover, the free radica...

Over the past two years, research on drift prospecting in the District of Keewatin has been directed towards developing reconnaissance and detailed sampling techniques that can indicate uranium mineralization a s well a s base metal mineralization. Shilts and Klassen (1976) have presented some preliminary results of the uranium phase for Boothia Peninsula and central Keewatin. The purposes of t...

We propose a generalization of the model of classical baker map on the torus, in which the images of two parts of the phase space do overlap. This transformation is irreversible and cannot be quantized by means of a unitary Floquet operator. A corresponding quantum system is constructed as a completely positive map acting in the space of density matrices. We investigate spectral properties of t...

We classify Baker domains U for entire maps with fj U univalent into three diierent types, giving several criteria which characterize them. Some new examples of such domains are presented, including a domain with disconnected boundary in C and a domain which spirals towards innnity.