The experimental evidence regarding Gibson's psychophysical hypothesis is examined. The presentation is divided into 2 sections dealing with static and transforming stimulation, respectively. Under the former heading the stimulation for surface, slant, and depth is considered. Under the latter heading the investigations of motion perspective, continuous perspective transformations, and size-tra...

Necessary and suucient conditions for minimality of descriptor representations of impulsive-smooth behaviors are derived. We obtain a complete set of transformations by which minimal descriptor representations that give rise to the same behavior can be transformed into each other. In particular this leads to a jump-behavioral interpretation of the notion of strong equivalence of descriptor repr...

Most strains of Helicobacter pylori are naturally competent for uptake of chromosomal DNA. Transformation frequencies for streptomycin resistance or rifampicin resistance markers ranged from 1 x 10(-4) to 1 x 10(-3) per viable cell using a plate transformation procedure. Transformation of a metronidazole resistance marker (MtrR) was demonstrated when either a laboratory-derived mutant or a MtrR...

We give new Bäcklund transformations (BTs) for some known integrable (in the sense of being multidimensionally consistent) quadrilateral lattice equations. As opposed to the natural auto-BT inherent in every such equation, these BTs are of two other kinds. Specifically, it is found that some equations admit additional autoBTs (with Bäcklund parameter), whilst some pairs of apparently distinct e...

Mature cystic teratoma (MCT) is the most common type of ovarian germ cell tumor occurring in females of reproductive age. It is typically benign, but rare malignant transformations have been reported in 1-2% of the cases. Among a wide variety of malignancies arising in MCTs, high grade lymphomas are the least common. We present a case of a 45- years -old female with a unilateral adnexal ma...

Although it is well known that epidermal growth factor receptor (EGFR) is involved in lung cancer progression, whether EGFR contributes to lung epithelial cell transformation is less clear. Mucin 1 (MUC1 in human and Muc1 in animals), a glycoprotein component of airway mucus, is overexpressed in lung tumors; however, its role and underlying mechanisms in early stage lung carcinogenesis is still...

PURPOSE The objective of this experiment was to compare the oncogenic potential of carbon ion beams and conventional photon beams for use in radiotherapy. METHODS AND MATERIALS The HeLa X human skin fibroblast cell line CGL1 was irradiated with carbon ions of three different energies (270, 100, and 11.4 MeV/u). Inactivation and transformation data were compared with those for 15 MeV photons. ...

It is estimated that up to 20% of all types of human cancers worldwide are attributed to viruses. The genome of oncogenic viruses carries genes that have protein products that act as oncoproteins in cell proliferation and transformation. The modulation of cell cycle control mechanisms, cellular regulatory and signaling pathways by oncogenic viruses, plays an important role in viral carcinogenes...