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In this book, we propose to describe what actually happened, as we saw it, in the schools of White Plains, New York, over a period of five years after a decision to integrate was implemented. Putting children together in one classroom is only a first step; it is desegregation rather than integration. The real work begins only after this first step has been taken. In the classroom, a teacher is now faced with: the age-old suspicion and distrust of black people; the "monumental hypocrisy" of whites; prejudice, blindness, and ignorance on both sides; two widely different sets of values, attitudes, and needs; and the disparity in academic standards created by the ghetto. All this must be dealt with patiently and realistically if integration is to become a fact. Both authors worked with the children discussed in this book, one as the classroom teacher, the other as a volunteer. The "I" in the book reflects our joint feelings and experiences. I came to teach sixth grade in White Plains in the fall of 1964, after several years' experience in the New York City public schools. I was to work in an elementary school that, until that year, had been entirely white and middle class. (Authors/JM)

Measurements of quantum efficiency to heavy charged particles, in particular to the proton, in the range of 5 to 2 MeV were made with windowless electron multipliers Qn cathodes of beryllium oxide and aluminum oxide. The effects of oxide thickness on quantum efficiency were determined and some qualitative explanations have been made based on the simple ionization process and escape probability of produced electrons. Using a Van de Graaff accelerator at beam currents of lnA to 5nA, precisions of measurement of better than 10% were obtainable with six different cathodes: three different thicknesses of BeO and three of Al2O3 respectively.

The data from a radon survey carried out in Larderello geothermal field are presented, together with a description of the methodology used. Discussion is limited to the most important factors affecting Rn concentration in the geothermal fluid.

Malate dehydrogenase has not revealed any consistent change of the percent ratio between its components during the post-natal maturation of the normal and dystrophic retina. The same minor change of the enzyme affinity for oxaloacetate has been measured after birth in both rat strains. Determinations of the specific activities of malate dehydrogenase and glyceraldehyde-3-phosphate dehydrogenase have not discriminated between normal rats and animals with inherited retinal degeneration. Glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase have exhibited different developmental curves in the two strains: post-natal drop of enzyme activity in normal rats, in contrast with the increase and subsequent decrease of both enzymes in affected animals.

Electrophoretic and catalytic studies have been carried out on lactate dehydrogenase of normal and transected sciatic nerves of the rat. Lactate dehydrogenase of the intact nerve exhibits an almost even distribution of activity among its component iso-enzymes. The complete transection of the nerve is responsible for a deep and immediate shift of the enzyme towards the so-called muscle type pattern. Seven days after the nerve section the percentage activity of iso-enzyme 5 is almost three times higher than in the intact nerve. After a short lag period lactate dehydrogenase specific activity (activity/mg protein) undergoes a sharp decrease in transected nerves. The return of the electrophoretic composition of the enzyme to a pattern similar to that of the intact nerve is not paralleled by any subsequent modification of specific activity. Some kinetic properties of the enzyme have shown changes parallel to those revealed by the electrophoretic analysis. The inhibition by excess lactate has exhibited, in fact, an increase and a subsequent decrease, which have been in keeping with the observed changes in the percentage activity of iso-enzyme 5 and related hybrid forms. Other kinetic parameters, such as the affinity for the substrates, have not shown significant modifications. The relationships of these neurochemical findings to the quantitative cytology of nerve degeneration and the metabolic significance of changes in the iso-enzymic patterns of lactate dehydrogenase are discussed.

The biochemical immaturity of the rat brain at birth has been largely investigated in recent years (see for references, Sperry, 1955, 1962; Himwich, 1962). It has been tempting to relate neurochemical data to older findings on the physiological maturation of the organ.

The Wallerian degeneration of the sectioned peripheral nerve has long been regarded as a merely regressive phenomenon. Some twenty years ago, Abercrombie and Johnson (1) did show, however, that a large increase of the number of nuclei within Schwann tubes and endoneurium is associated with regressive events of nerve degeneration. This article provides a preliminary answer to the question as to whether changes in the isoenzymic composition of LDH (lactate dehydrogenase) can be determined by experimental induction of cell proliferation and degeneration in a defined nervous tissue such as the distal segment of a cut nerve. Molecular changes of LDH's in growing and spontaneously degenerating nervous tissues have been recently reported by Bonavita et al. (2, 3, 4). The sciatic nerve of the rat has been chosen since previous studies in our laboratory (2,3,4) have provided data on the electrophoretic and catalytic properties of the enzyme in the nervous tissues of this species.

At first the AA. present the recent progresses reached in the Endocrinology diagnostic with the aid of the radioisotopic techniques; successively they refer about the principles regulating the chemical reactions used in the dosage of the single hormones and about the use of index interesting the clinical practice. The AA. compare the methods of dosage used in the kits of various firms outlining the problems concerning the technological times, the operations number, the contamination risk. They performed several control tests on the T3 RIA, recently introduced into the clinical diagnostic, on the calibration curve, on the repeatibility of the results, on the recovery tests, on the sensitivity of the tarature curve, showing the normal and abnormal values obtained in their hospital. They refer moreover on the results obtained dosing together on the same samples T4, TBC, ETR, T3, RIA, TSH and on the clinical utility of the single tests. Several dosages of T3 and of T4 were effected on urine to have informations on the urinary excretion levels of the thyroid hormones in normal and abnormal subjects. At last they hypothesize the use of the hormonal urinary values and the plasmatic ones for calculating an ormonal thyroid clearance.