Growth-controlled synthesis of polymer-coated colloidal-gold nanoparticles using electrospray-based chemical reduction

In this study,the controlled nucleation and growth of gold nanoparticles(GNPs)were investigated using a self-repelled mist in a liquid chemical reaction environ...     

Biocompatibility of some materials used in dental implantology: histological study

This study deals with bioreactive materials for potential applications as endosseus dental implants. Currently used dental implants are made of dental alloys but due to cytotoxic problems, high strength ceramic materials appear as an interesting alternative to these alloys. In order to combine good mechanical properties and promotion of the osteointegration process, a ceramic composite material composed of 10 wt.% tricalcium phosphate (TCP) mixed with partially stabilized zirconia has been elaborated. Such a ceramic has been implanted into albino rats, the sites of implantation being the adrenal gland for the toxicity evaluation and the sphenoid bone to estimate the osteogenesis potential. These results have been compared to those obtained with implants made of alumina (Al₂O₃), zirconia (ZrO₂) or poly(ethylene terephthalate) (Dacron®). In all cases no rejection effect was observed. The histological study indicated that ZrO₂-TCP ceramics induced a marginal and subjacent cell disorganization. However, the existence of an irregular cellular band indicated a cellular colonization process on the TCP particles. The microscopy study of the implants after removal confirmed the bioresorption of TCP.     

Total synthesis of asperlicin D

Cyclodehydration of a linear tripeptide furnished the first total synthesis of asperlicin D in moderate yield. The cyclodehydration process was triggered by an intramolecular nucleophilic acyl substitution and an intramolecular aza-Wittig reaction.     

A facile rearrangement of pyrroloindoline derivative to pyrroloquinoline: A new analogues of duocarmycins

Free‐radical generated at C‐7 position of indole derivative bearing N‐(3′‐chloroallyl) group prompted a regioselective intramolecular cyclization to furnish pyrroloindoline derivative, through the more favorable 5‐exo‐trig cyclization mode. The pyrroloindoline compound smoothly rearranged to pyrroloquinoline under mild conditions.     

A Simple Preparation of 1-Substituted Uracils

Reaction of isocyanates with 3,3-diethoxypropionamide gives diethoxy acyl ureas which may be conveniently cyclized to 1-substituted uracils.     

Inertial Alfven waves in an inhomogeneous bi-Maxwellian plasma

The Vlasov kinetic equation is solved using gyrokinetic theory and the dielectric tensor for non-relativistic, magnetized, bi-Maxwellian plasmas is calculated. A generalized dispersion relation for kinetic Alfven waves is derived taking into account the density inhomogeneity and temperature anisotropy. The modified dispersion relation thus obtained is then used to examine the propagation characteristics of the kinetic Alfven waves in the inertial regime. The importance of density inhomogeneity and temperature anisotropy for Solar corona is highlighted. The growth rate of the inertial Alfven wave proves that density inhomogeneity acts as a source of free energy.     

Output controllability and optimal output control of positive fractional order linear discrete system with multiple delays in state, input and output

The article concerns output controllability and optimal output control of positive fractional order discrete linear systems with multiple delays in state, input and output. Necessary and sufficient conditions for output reachability (output controllability from zero initial conditions) and null output controllability (output controllability to zero final output) are given and proven. We also prove that the positive system is output controllable if it is output reachable and null output controllable with the output reachability index is equal or less than the null output controllability index. Sufficient conditions for the solvability of the optimal output control problem are given. Numerical examples are presented to illustrate the theoretical results.