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The central focus of this study was an analysis of social science research that had been supported by the U. S. Office of Education's Small Grant Research Program (SGRP). Background information was provided on the objectives and procedures of the SGRP. Information was provided on some 25 social science projects that had received support through the regional Offices of Education. In addition to summary accounts of the individual projects, a matrix was provided to identify the level (elementary, secondary, higher education, all-general), the focus (research, training, curriculum, all-general), and the research area (anthropology, archaeology, economics, American history, world history, humanities, political science, social studies, sociology, psychology). The status, trends, and needs in social studies research were noted in the activities of specialized projects and through interviews with eminent scholars in the field. It was suggested that research efforts be expanded, a greater effort be made for effective dissemination in the social studies area, and that all agencies and professionals develop a new spirit of cooperation to better delineate the problems and avenues for solution in the complex arena of social sciences. A continuing need will be that of keeping the practitioner adequately informed as to the developments in the field. (Author)

Cardiac muscle fibers of the hummingbird and finch have no transverse tubules and are smaller in diameter than those of mammalian hearts. The fibers are connected by intercalated discs which are composed of desmosomes and f. adherentes; small nexuses are often interspersed. As in cardiac muscle of several other animals, the junctional SR of the couplings is highly structured in these two birds but, in addition, and after having lost sarcolemmal contact, the junctional SR continues beyond the coupling to extend deep into the interior of the cells and to form belts around the Z-I regions of the sarcomeres. This portion of the sarcoplasmic reticulum, which we have named "extended junctional SR," and which is so prominent and invariant a feature of cardiac cells of hummingbirds and finches, has not been observed in chicken cardiac cells. The morphological differences between these species of birds may be related to respective differences in heart rates characteristic for these birds.

The pellicle complex of E. gracilis is composed of the cell membrane, the ridge and groove with the notch, four fibrils, and the subpellicular ER. The cell membrane is of unit membrane configuration and covers the outside of the cell, the cytostome, the gullet, and the reservoir. The notch of the pellicle complex has always a close topographic relationship to two particular fibrils, as well as the subpellicular ER. The gullet is that region between the reservoir and the cytostome which, in addition to longitudinal fibrils, is surrounded by a single row of circular fibrils. The circumference of the cytostome has twenty large pellicular ridges alternating with small pellicular ridges. Alternating tall and small pellicular ridges cover the entire cell during division.

The structure of a small strand of rabbit heart muscle fibers (trabecula carnea), 30–80 µ in diameter, has been examined with light and electron microscopy. By establishing a correlation between the appearance of regions of close fiber contact in light and electron microscopy, the extent and distribution of regions of close apposition of fibers has been evaluated in approximately 200 µ length of a strand. The distribution of possible regions of resistive coupling between fibers has been approximated by a model system of cables. The theoretical linear electrical properties of such a system have been analyzed and the implications of the results of this analysis are discussed. Since this preparation is to be used for correlated studies of the electrical, mechanical, and cytochemical properties of cardiac muscle, a comprehensive study of the morphology of this preparation has been made. The muscle fibers in it are distinguished from those of the rabbit papillary muscle, in that they have no triads and have a kind of mitochondrion not found in papillary muscle. No evidence of a transverse tubular system was found, but junctions of cisternae of the sarcoplasmic reticulum and the sarcolemma, peripheral couplings, were present. The electrophysiological implications of the absence of transverse tubules are discussed. The cisternae of the couplings showed periodic tubular extensions toward the sarcolemma. A regularly spaced array of Z line-like material was observed, suggesting a possible mechanism for sarcomere growth.

With light and electron microscopy a comparison has been made of the morphology of ventricular (V) and Purkinje (P) fibers of the hearts of guinea pig, rabbit, cat, dog, goat, and sheep. The criteria, previously established for the rabbit heart, that V fibers are distinguished from P fibers by the respective presence and absence of transverse tubules is shown to be true for all animals studied. No evidence was found of a permanent connection between the sarcoplasmic reticulum and the extracellular space. The sarcoplasmic reticulum (SR) of V fibers formed couplings with the sarcolemma of a transverse tubule (interior coupling) and with the peripheral sarcolemma (peripheral coupling), whereas in P fibers the SR formed only peripheral couplings. The forms of the couplings were identical. The significance, with respect to excitation-contraction coupling, of the difference in the form of the couplings in cardiac versus skeletal muscle is discussed together with the electrophysiological implications of the differing geometries of bundles of P fibers from different animals.

Nach mehrwochigem intensiven Schwimm- bzw. Lauftraining nimmt in der Hinterbeinmuskulatur der Ratte die Oxydationskapazitat fur Pyruvat um das Doppelte zu. Parallel dazu sind die Cytochromgehalte und die Aktivitatsgehalte strukturgebundener mitochondrialer Enzyme (Glycerin-1-phosphat-Oxydase, Succinatdehydrogenase) im trainierten Muskel etwa doppelt so gros wie im untrainierten. Auch der Mitochondrienproteingehalt nimmt signifikant zu im Vergleich zu den Werten von untrainierten Kontrolltieren. In Ubereinstimmung damit wird in Schnitten von trainierten Muskeln, die elektronenmikroskopisch untersucht wurden, eine deutliche Vermehrung von Zahl und Cristaegehalt der Mitochondrien beobachtet. Diese Befunde weisen darauf hin, das der Aktivitatsanstieg der Atmungsenzyme auf eine de novo-Synthese von Enzymprotein zuruckzufuhren ist. Die Atmung von Mitochondrien, die aus trainierten Muskeln isoliert wurden, ist eng mit der Phosphorylierung gekoppelt. Aus der Zunahme der Atmungsaktivitat resultiert somit fur den trainierten Muskel eine vermehrte Kapazitat zur Bildung von energiereichen Phosphaten. Im System des anaeroben Muskelstoffwechsels (Glykolyseenzyme und Glykolysemetabolite) lassen sich dagegen trainingsbedingte Veranderungen nicht nachweisen. Lediglich der Glykogengehalt nimmt nach 5 wochigem Schwimmtraining um etwa 50% zu.

Lymphocytes from a patient with lymphocytic leukemia were found to contain cytoplasmic globules. The globules varied in size, the largest appearing identical to Russell bodies. Histochemical staining was used to demonstrate the glycoprotein composition of these bodies. Electron microscopy revealed this material to be within dilated cisternae of rough endoplasmic reticulum. It is proposed that these globules are abnormal accumulations of glycoprotein which represent stages in the evolution of "Russell bodies." The generic description of these cytoplasmic globules would seem to be preferable to the continued use of eponyms.

The granules of the eosinophilic myeloid cells of normal human bone marrow exerted a pronounced activity to dephosphorylate adenosine triphosphate. This behavior was not shown by the granules of other myeloid cells.

The localization of induced and constitutive acid phosphatase activity in Euglena was studied by light and electron microscopy, using two different cytochemical methods. Cells grown in high phosphate medium have constitutive acid phosphatase activity in three regions: in the Golgi complex, around the paramylum bodies, and in the peri-reservoir vesicles. Cells that have formed an induced acid phosphatase by exposure to a phosphate-deficient medium have, in addition to the constitutive activity localized exactly as in the uninduced cell, a strong activity in the pellicle. The induced activity is not uniformly distributed over the pellicle, but is localized at the notch of each pellicle complex, near a group of about four fibrils and near a characteristic vesicle of the endoplasmic reticulum. In the cytostome, where fission begins during division, there is an alternation of large and small pellicle complexes, both of which have induced phosphatase activity. A similar alternation is seen over the entire pellicle of dividing cells.

SYNOPSIS. The relationship between Astasia longa and a streptomycin-bleached strain of Euglena grocilis has been examined by several criteria. The organisms differ in their sensitivity to actinomycin D and 8-azaguanine in their ability to incorporate C14-labeled leucine, and in their sensitivity to a new antibiotic called primycin. Euglena forms an induced acid phosphatase when grown in phosphate-deficient medium, but Astasia does not. On the basis of these and other differences, it is suggested that these two organisms are separate genera. Understanding of cell division in these cells has been increased by discovery of an array of tubular fibrils corresponding to a spindle apparatus in the nucleus of a dividing Astasia. This finding, plus the observation that presumptive pellicle complexes are formed during prophase, clarify the fission mechanisms in these organisms.

An impregnation technique for demonstration of mitochondria in central nervous system has been described. Formol perfused material is being chromated, embedded in paraffin and impregnated with a modified Nauta's method. The reaction is specific since reduced silver particles are deposed within the matrix of mitochondria. Phenomenon of complete and incomplete impregnation is discussed. Mitochondria in perikarya of neurons, dendrites and glia tend to be unstained if the impregnation is incomplete, while axonic and praesynaptic ones are labelled. In neuropil of different regions of the brain various types of mitochondrial aggregates appear in complete impregnation. The method may be a valuable tool for studying brain architecture and synaptology.

Among animal hearts, there are many differences in the anatomic features of various myocardial cells, the occurrence of junctional complexes joining adjacent cells, the geometry of apposition of cells forming bundles of fibers, and the form and extent of specializations of intracellular membrane systems. The working fibers of chicken and frog hearts, which have no transverse tubules, are considerably smaller in diameter than those of their mammalian counterparts, which do have such tubules. Purkinje fibers in the hearts of small mammals differ in structure and appositional geometry from those of the larger mammals, and again from those of the chicken. All Purkinje fibers lack transverse tubules. Focal specializations of the sarcoplasmic reticulum, the junctional sarcoplasmic reticulum, are prominent in chicken and mammalian, but not in frog cardiac muscle. Gap junctions are frequent in mammalian hearts, but seem to be rare, small or absent altogether in both frog and chicken hearts.