Does synchronization of networks of chaotic maps lead to control?

We consider networks of chaotic maps with different network topologies. In each case, they are coupled in such a way as to generate synchronized chaotic solutions. By using the methods of control of chaos we are controlling a single map into a predetermined trajectory. We analyze the reaction of the network to such a control. Specifically we show that a line of one-dimensional logistic maps that are unidirectionally coupled can be controlled from the first oscillator whereas a ring of diffusively coupled maps cannot be controlled for more than 5 maps. We show that rings with more elements can be controlled if every third map is controlled. The dependence of unidirectionally coupled maps on noise is studied. The noise level leads to a finite synchronization lengths for which maps can be controlled by a single location. A two-dimensional lattice is also studied.     

Use of immobilized Candida yeast cells for xylitol production from sugarcane bagasse hydrolysate

Applied Biochemistry and Biotechnology - Candida guilliermondii cells were immobilized in Ca-alginate beads and used for xylitol production from concentrated sugarcane bagasse hydrolysate. A full...     

Internal pressure and cohesive energy density for binary non-electrolyte mixtures

Internal pressures and cohesive energy densities of binary liquid mixtures of n-pentane+dichloromethane, n-pentane+methylacetate, 2-propanol+methylacetate and n-bytylamine+1,4-dioxane at 25°C have been evaluated from molar volumes surface tensions and enthalpies. The data obtained provide information about interactions in the binary liquid mixtures which can be correlated with results from other thermodynamic properties.Presented at the VI Congreso Argentino de Fisicoquímica, Santiago del Estero, Argentina, 1989.     

A conditional least squares approach to PGARCH and PARMA–PGARCH time series estimation

In this Note, a conditional least squares (CLS) estimates for periodic GARCH (PGARCH) models with martingale difference centered squared innovations is developed. The approach is extended to the PARMA–PGARCH models. We establish the strong consistency and the asymptotic normality for our estimate.     

Structural Refinement of 2,4-Thiazolidinedione Derivatives as New Anticancer Agents Able to Modulate the BAG3 Protein

The multidomain BAG3 protein is a member of the BAG (Bcl-2-associated athanogene) family of co-chaperones, involved in a wide range of protein–protein interactions crucial for many key cellular pathways, including autophagy, cytoskeletal dynamics, and apoptosis. Basal expression of BAG3 is elevated in several tumor cell lines, where it promotes cell survival signaling and apoptosis resistance through the interaction with many protein partners. In addition, its role as a key player of several hallmarks of cancer, such as metastasis, angiogenesis, autophagy activation, and apoptosis inhibition, has been established. Due to its involvement in malignant transformation, BAG3 has emerged as a potential and effective biological target to control multiple cancer-related signaling pathways. Recently, by using a multidisciplinary approach we reported the first synthetic BAG3 modulator interfering with its BAG domain (BD), based on a 2,4-thiazolidinedione scaffold and endowed with significant anti-proliferative activity. Here, a further in silico-driven selection of a 2,4-thiazolidinedione-based compound was performed. Thanks to a straightforward synthesis, relevant binding affinity for the BAG3BD domain, and attractive biological activities, this novel generation of compounds is of great interest for the development of further BAG3 binders, as well as for the elucidation of the biological roles of this protein in tumors. Specifically, we found compound 6 as a new BAG3 modulator with a relevant antiproliferative effect on two different cancer cell lines (IC₅₀: A375 = 19.36 μM; HeLa = 18.67 μM).     

Medium Initial pH and Carbon Source Stimulate Differential Alkaline Cellulase Time Course Production in Stachybotrys microspora

The production profile of cellulases of the mutant strain A19 from the filamentous fungus Stachybotrys microspora was studied in the presence of various carbon sources (glucose, lactose, cellulose, carboxymethylcellulose (CMC), and wheat bran) and a range of medium initial pH (5, 7, and 8). Two extracellular cellulases from the Stachybotrys strain (endoglucanases and β-glucosidases) were monitored by enzymatic assay, sodium dodecyl sulfate–polyacrylamide gel electrophoresis, and zymogram analysis. Glucose and lactose repressed CMCase time course production while they permitted a strong β-glucosidase one. On Avicel cellulose, CMC, and wheat bran, both activities were highly produced. Wheat bran (WB) is the best carbon source with an optimum of production at days 5 and 6. The production kinetics of both activities were shown to depend on the medium initial pH, with a preference for neutral or alkaline pH in the majority of conditions. The exception concerned the β-glucosidase which was much more produced at acidic pH, on glucose and cellulose. Most interestingly, a constitutive and conditional expression of an alkaline endoglucanase was revealed on the glucose-based medium at an initial pH of 8 units. The zymogram analysis confirmed such conclusions and highlighted that carbon sources and the pH of the culture medium directed a differential induction of various endoglucanases and β-glucosidases.     

Solid-state tubular assemblies of thiolactones: synthesis and structural characterization

The synthesis of cyclic thiolactones, 2,5,8-trithiacyclododecane-1,9-dione (4), 2,5,8,14,17,20-hexathiacyclotetracosane-1,9,13,21-tetraone (5), 2,5,8-trithiacyclotetradecane-1,9-dione (6) and 2,5,8,16,19,22-hexathiacyclooctacosane-1,9,15,23-tetraone (7) was achieved by tin-template reaction of 2,2-dibutyl-2-stanna-1,3,6-trithiacyclooctane (1) with corresponding diacyl chlorides. The structures of 12-, 14-, 24- and 28-membered ring systems of 4, 6, 5, and 7, respectively, were investigated by X-ray structure analysis. These investigations revealed that, in the solid-state, thiolactones 4 and 7 form tubular assemblies. However, the crystal structure of 5 forms layered packing dominated by CH?O hydrogen bonds whereas 6 forms three-dimensional network via CH?O hydrogen bonds and van der Waals interactions.