Poly(L‐lactic acid) with added α‐tocopherol and resveratrol: optical,physical, thermal and mechanical properties

Poly(L ‐lactic acid) (PLLA) films containing various concentrations of two natural antioxidants, α‐tocopherol and resveratrol, were fabricated by a melt compounding and compression molding process. The influence of the antioxidants on the optical properties such as color and UV‐visible light transmission was analyzed. The thermal, mechanical, rheological and physical properties of PLLA films with added antioxidants were assessed. PLLA films with added α‐tocopherol and resveratrol showed a yellowish brown color and the lightness was influenced by the presence of the antioxidants. The glass transition and melting temperatures were significantly reduced with the addition of antioxidants while enhanced thermal stability was observed, which could be a benefit and important for processing and production. PLLA films with added antioxidants were slightly more hydrophobic than neat PLLA. The combination effect of plasticizing and enhancement of the elastic modulus with differing concentrations of two antioxidants played a critical role in the mechanical and thermomechanical properties of PLLA films. The melt viscosity of the PLLA films with added antioxidants was substantially higher than that of neat PLLA. The higher melt viscosity and G′(ω) could be an indication of formation of entanglement between PLLA and the two antioxidants. Copyright © 2012 Society of Chemical Industry     

Refusal to eat in the elderly

Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process.     

Orientation in operator algebras

A concept of orientation is relevant for the passage from Jordan structure to associative structure in operator algebras. The research reported in this paper bridges the approach of Connes for von Neumann algebras and ourselves for C*-algebras in a general theory of orientation that is of geometric nature and is related to dynamics.     

The application of alumino silicate alkali ion sources to the study of ion desorption of surface gas

Investigations are described which illustrate the compatibility of alumino silicate alkali ion sources with an UHV (～10^?11 torr) vacuum environment. The application of the sources to the determination of ion desorption efficiency of surface gas is demonstrated, as well as their use as a basis for a technique of ion stimulated surface gas analysis.     

The therapeutic success of an analytic group-psychotherapy demonstrated objectively by the Giessen-test (author''s transl)

Results of follow-up examinations of 132 ears with serous or mucous middle ear effusions indicate that this disease is common in childhood and is also found in adults. In childhood adenoid growth as well as repeated catarrhal infection of the paranasal sinuses and the weakness of the levator palati play an important role in the development of middle ear effusions and deafness. With the aid of the operation microscope we were able to recognize this characteristic disease through the tympanic membrane. We perform regularly adenoidectomy together with paracentesis in this condition. In cases which had undergon several adenoidectomies we limit our treatment in the first instance to paracentesis. If cure is not so achieved we insert an inert tube into the tympanic membrane after the paracentesis. In persistent and difficult cases of glue ear radiation of the eustachion tube and antrotomy may be necessary.