Mesoscale Simulations of Structure Formation in Polyacrylonitrile Nascent Fibers Induced by Binary Solvent Mixture.

Polyacrylonitrile (PAN) is widely used as a raw material for the production of high-modulus carbon fibers, the internal structure of which is directly affected by the spinning of the precursor. Although PAN fibers have been studied for a long time, the formation of their internal structure has not been sufficiently investigated theoretically. This is due to the large number of stages in the process and the parameters controlling them.

DELAYED SURGERY FOR GIANT SPONTANEOUS RUPTURE OF THE DISTAL THORACIC AORTA CAUSED BY CYSTIC MEDIAL NECROSIS.

Spontaneous (idiopathic) thoracic aortic rupture (STAR) is uncommon and assumes a rupture of the normal-sized thoracic aorta with no visually apparent aortic disease. Since 1961 about fifty reports have been published. STAR is established in cases of thoracic normal-sized aorta rupture with no traumas, aneurysms/dissections, infection, inflammation, connective tissue diseases, aortic and adjacent organs tumors/metastases, previous surgery, and occurring during pregnancy and the peripartum.

Surgery for Ascending Aortic Aneurysm and Aortic Valve Insufficiency in Conditions of Active Proceeding Syphilitic Aortitis and Valvulitis.

A syphilitic aortitis is a late cardiovascular lesion of tertiary syphilis that has become exceptionally rare in the antibiotic era but not eradicated completely. Syphilitic aortitis of ascending aorta complicates in ascending aortic aneurysm formation and aortic valve regurgitation, both requiring surgical treatment. After surgery, lifelong surveillance of the remainder of the aorta is recommended because of a priori supposed high incidence of delayed involvement of noninvolved aortic segments.

Self-assembly in systems based on L-cysteine-silver-nitrate aqueous solution: multiscale computer simulation.

We use fully atomistic, quantum mechanics and mesoscopic simulations to investigate multiscale structure formation in a supramolecular system based on aqueous solutions of silver nitrate with L-cysteine (CSS). Fully atomistic modeling reveals that silver mercaptide clusters are formed in solution at the stage of aging, which has a pronounced "core-shell" structure. The core is formed due to the bonding of SAg groups of silver mercaptide (SM) zwitterions while the shell consists of NH and C(O)O groups.

Effect of visible light onto self-assembly in l-cysteine-silver solution.

Effects of irradiation with visible light on the process of self-assembly in an aqueous l-cysteine-silver solution (CSS) and hydrogels based on were investigated using a set of physico-chemical methods. It was found that the exposure to light of CSS and hydrogels based on l-cysteine and silver acetate colors them firstly into yellow and subsequently to brown, which is due to the plasmon resonance of free electrons at the surface of resulting silver nanoparticles (AgNPs). A mechanism involving participation of AgNPs was proposed for the self-assembly in CSS and hydrogel.