Higher Degree Of Organization Research Articles

PEDIATRIC PERCEPTIONS: DELIVERY OF HEALTH SERVICES FOR HANDICAPPED CHILDREN AND YOUNG ADULTS IN EUROPE

In all European countries visited there is evidence of considerable progress in the development of imaginative and flexible programs for the care of handicapped children and youth. This is true of efforts directed toward prevention and early case finding, and in the provision of both ambulatory and residential care. Admission to an institution for the child or young adult does not necessarily end in lifelong incarceration. In most instances it is assumed that, with proper and aggressive management, progress will be achieved and that, as the child needs change, appropriate modifications in his overall plan of treatment can and will be made. Our observations reveal that general medical care programs do not, in themselves, ensure that children and youth will receive needed medical care. This is likely to happen only when a special organizational unit at the national level is charged with the responsibility of evaluating and delivering care to this uniquely vulnerable-and readily identifiable-segment of the population. As traditional professional and institutional methods become obsolescent, improved health services for children and youth will require an even higher degree of organization at national, state and local levels. It would seem important for us in the United States to capitalize fully on experience gained in other countries whose health problems are not fundamentally different than our own.

Liquid-crystalline structures in polypeptide solutions

INTRODUCTION IN this paper the remarkable properties, including the very high optical rotatory power, of a liquid crystalline phase which is formed by certain polypeptide solutions will be discussed. Although liquid crystals have attracted much interest since their discovery in I888r (a recent review article contained as many as 475 references)* many physical chemists seem to be unfamiliar with the subject. It may therefore be helpful to state briefly what is meant by this rather unsatisfactory term. Most crystals pass directly at their melting point from the crystalline state to an isotropic liquid, but many crystalline solids pass through one or more mesophases which, though birefriogeot, are more or less fluid. These mesophases have various degrees of orgaoisation but most can be described by one or other of two terms introduced by Friedel : smectic and oematic.3 In the smectic structure the molecules are arranged in layers, which are themselves arranged in families of closed surfaces known as Dupio cyclides, which give rise to focal tonics which are visible in a polarization microscope and can be used for the identification of such structures. These smectic structures and the microscopic patterns associated with them have been adequately described elsewhere.‘4 The oematic structure, which is the only one of the two classes with which this paper is concerned, has a lower degree of organization that the smectic; there are no layers, but the molecules are arranged with their long axes parallel, while being free to move relative to one another in the direction of these axes. Friedel also described a third, though less familiar, type of structure, met with chiefly in esters and ethers of cholesterol, which is related to the oematic structure but which has a higher degree of organization. IO what follows it will be found that these last have much in common with those which have been found to occur in certain polypeptide solutions. A given material may form one or several mesophases each of which is stable between two well defined and reproducible transition temperatures and the temperature range over which any one is stable may cover a considerable number of degrees. These mesomorphic forms are not only produced on heating certain solids but with some substances (e.g. soaps, and the polypeptides to be discussed in what follows) on adding a limited amount of a suitable solvent. In these cases the mesophase may be stable over a considerable and reproducible range of concentration, which will, however, depend on the temperature. Such mesophases, whether formed by changes of temperature or addition of solvent, are generally called liquid crystals or liquid crystalline