Water based silicone elastomer controlled release tablet film coating V - A statistical approach

The silicone elastomer latex formulated with polyethylene glycol and colloidal silica produced a controlled release film coating on potassium chloride tablets. The release rate of potassium chloride was controlled by the total amount of polyethylene glycol and the weight fraction of polyethylene glycol 8000 and 1450 incorporated in the coating. A mathematical model was developed to quantitate the effect of coating components on the drug release rate using the statistical extreme vertices design. The predictive capability of this functional relationship was tested and validated experimentally.     

Energy function analysis of dynamic programming neural networks

All analytical examination of the energy function associated with a dynamic programming neural network is presented. The analysis is carried out in two steps. First, the locations and numbers of the minimum states for different components of the energy function are investigated in the extreme cases. A clearer insight into the energy function can be gained through the minimum states of different components. Secondly, the locations of the minimum states of the energy function using different parameter values are derived. It is shown that the minimum states can reside in regions which are regarded as valid solutions with certain conditions. Examples and simulation results are given to justify the validity of the theories developed.     

A survey of transformation markers in differentiating epidermal cell lines in culture

Primary mouse epidermal cells underwent spontaneous malignant transformation in culture. TWelve malignant epidermal cell lines were established which produced squamous cell carcinomas in syngeneic hosts. These lines were used to define criteria for recognizing transformed epidermal cells in vitro. Growth in suspension in agar, agarose, or Methocel was minimal for 11 of the lines. All lines tested retained specific epidermal antigens (pemphigus, pemphigoid, keratin) by indirect immunofluorescence, but keratin content was reduced when quantified by radioimmunoassay. Basal activity of ornithine decarboxylase and activity induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate were variable among lines. All malignant lines as well as normal epidermal cells grew well at reduced extracellular calcium concentrations. When the extracellular calcium was elevated, normal cells ceased proliferation, terminally differentiated, and sloughed from the culture dish, while malignant cells continued to proliferate although they expressed differentiative functions. These results indicate that malignant transformation in epidermis is associated with a fundamental alteration in the program of terminal differentiation which allows some cells to escape the proliferative block and cell death which accompanies differentiation in normal keratinocytes. This alteration should be useful to select for transformants during the process of carcinogenesis in vitro.     

Flexible Transparent ZnO:Al/ZnO/CuAlO x :Ca Heterojunction Diodes on Polyethylene Terephthalate Substrates

Transparent flexible n ⁺-ZnO:Al (100 nm)/n-ZnO (40 nm)/p-CuAlO _x :Ca (100 nm, 200 nm, 300 nm) diodes were fabricated on polyethylene terephthalate substrates at room temperature using a sputtering technique. No additional heat treatment was performed on the fabricated devices. Increase of the diode layer thickness reduced the on-current and leakage-current levels simultaneously, which led the rectification ratio to first increase and then decrease as the p-layer thickness increased. The ultraviolet (UV) response of the diode was also investigated under irradiation at 365 nm. The n ⁺-ZnO:Al (100 nm)/n-ZnO (40 nm)/p-CuAlO _x :Ca (200 nm) diode exhibited photocurrent/leakage current ratio of 1.03 × 10³ and responsivity of 0.64 A/W at reverse bias of ?6 V when measured in flat status. The corresponding photocurrent/leakage current ratio and responsivity were 7.99 × 10² and 0.65 A/W, respectively, for an outwardly bent diode with 5.5 cm radius of curvature. The increases of current levels under bending are attributed to the decreases of series resistance for the diode under tensile strain.