Novel photoluminescent mesogenic Schiff-base ligands bearing [N4O4] donors and their bimetallic Zn(II) complexes

Novel photoluminescent salicylaldimine ligands condensed from 3^/, 3^/, 4^/, 4^/-tetraminobiphenyl and 4-substituted long alkoxy salicylaldehyde possessing two sets of tetradentate [N₂O₂] donor site and their binuclear zinc(II) complexes have been synthesized. The mesogenic and photophysical properties were investigated. The compounds were characterized by FT-IR, ¹H and ¹³C NMR, UV–vis, elemental analyses, solution electrical conductivity measurements and FAB mass spectrometry. The mesomorphic behavior of these compounds was probed by differential scanning calorimetry and polarized optical microscopy. The ligand with six carbon chain length showed monotropic nematic mesomorphism at 128° C. However, the ligand with alkoxy tail of carbon length 12 showed enantiotropic SmC phase. The complexes are devoid of any mesomorphism. The low molar conductance values in CH₂Cl₂ indicate that the complexes are non-electrolytes. At 330 nm excitation, the ligand emits green light at ~ 516 nm (Φ = 30%) and ~ 549 nm (Φ = 16%) in solution and solid state, respectively. At similar excitation wavelength, the complexes exhibit blue light in solution at ~ 452 nm (Φ = 20%) and green light in solid state ~ 555 nm (Φ = 11%). The DFT calculations were performed using DMol3 program at BLYP/DNP level to ascertain the stable electronic structure of the complex.     

A moderate consumption of Côtes du Rhône red wines affects the progression of aortic lesions,and reduces oxidative stress and p22<Superscript>phox</Superscript>NADPH oxidase activation in an experimental model of diet-induced atherosclerosis,according to the vinification process

Côtes du Rhône red wines prepared from both different types of grape and processing were tested in hamsters receiving an atherogenic diet for 12 weeks and a daily gavage with 12% ethanol, red wines from vinification by flash release (GRE FD, SYR FD and BLEND FD), by tanisage (BLEND TAN), by traditional vinification (BLEND), or water as control. Except BLEND TAN, consumption of wines lowered plasma total and LDL-cholesterol. Aortic lipid deposits were reduced by ethanol (30%), wines (54% on average) or BLEND TAN (65%). Cardiac production of superoxide anion decreased from 20% (BLEND and BLEND TAN) to 33% (SYR FD and BLEND FD). The expression of NAD(P)H oxidase decreased by 44% (SYR FD), 26% (BLEND), 47% (BLEND FD) and 44% (BLEND TAN). Except ethanol and GRE FD, wines increased uricemia by 15% on average. These findings indicate that chronic consumption of red wine has potential beneficial effects to prevent the development of atherosclerosis. Prevention of NAD(P)H oxidase induction and preservation of aortic lipids oxidation likely contribute to this effect.     

An agent-based approach to knowledge management in distributed design

The collaboration process among individuals with heterogeneous skills in a distributed virtual environment represents a crucial element of the extended enterprise. In order to achieve global optima in design, there is an increasing need for design teams to establish and maintain cooperative work through effective communication, co-location, coordination and collaboration at the knowledge level. Because of the distributed nature of users and information resources involved in the design process, the need for appropriate knowledge management tools is imperative. This paper proposes an agent-based architecture to support multi-disciplinary design teams that cooperate in a distributed design environment (DDE). Using ontologies and multi-agent systems (MAS), the proposed framework aims to optimise design process operation and management by supporting the dialogue among distributed design actors. Received: February 2005/Accepted: January 2006