Why Doesn't the Creed Read "Always Be Critical"? An Examination of a Liberal Curriculum

Using ethnographic data collected in a second grade classroom over the course of a school year, this paper describes the ways in which one school's discourse of liberalism is deleteriously deployed. We view the school's discipline creed as emblematic of the school's liberal curriculum, and interrogate the effects on four African American boys in the classroom when the school enacts this creed. Despite the agency that these boys obviously had, they were unable to control the ways in which they were placed at a structural disadvantage and manipulated by a system far more powerful than they were. The results were that these four boys suffered. Not only did the intended liberal curriculum fail to be translated fully into the enacted curriculum, the liberal underpinnings of this curriculum precluded teachers and students from taking any critical stance.     

[14C]-Glucose Metabolism during Shoot Bud Development in Cultured Cotyledon Explants of Pinus radiata

Excised cotyledons of Pinus radiata D. Don cultured under shoot-forming(plus benzyladenine) and non shoot-forming (minus benzyladenine)conditions for 10 and 21 days were fed U-[¹⁴C]-glucose for 3h in the light followed by a 3 h chase period. The labellingof individual metabolites as well as ¹⁴C incorporation intoprotein was assessed. It was found that the general metabolicpatterns were qualitatively the same in shoot-forming and nonshoot-forming conditions, however, metabolism leading to respirationas well as to the synthesis of some amino acids and proteinsynthesis was enhanced in the shoot-forming cultures. (Received February 16, 1987; Accepted July 8, 1987)     

Changes in the antigenic phenotype of mouse thymocytes after exposure to chemical inducers of differentiation and ionizing radiation

Irradiation of a mouse thymocyte fraction enriched by T-lymphocyte precursors changes the antigenic phenotype of cells toward the increase of their highly differentiated forms. Similar changes in membrane marker antigens are produced by chemical inductors of differentiation and thymotropin. The changes in the cell phenotype induced by the above agents are associated with both membrane and intragenome rearrangements. The results of the experiments on preventing the expression of some antigens by puromycin and the data on the level of spontaneous genome lesions in thymocyte fractions have prompted an assumption that destabilization of the genome upon irradiation increases DNA injury above some critical level which may serve a stimulus for "sorting out" the most radiosensitive thymocyte fraction.     

Ascorbic acid enhancement of organogenesis in tobacco callus

The effect of ascorbic acid on growth and shoot formation in callus cultures of tobacco (Nicotiana tabacum L.) was investigated, using young (4–12 subcultures) and old (more than 30 subcultures) tissue. It was found that ascorbate, at levels of 4–8×10^-4M, enhanced shoot formation in both young and old callus. Treatment with ascorbate also speeded up the shoot-forming process. In addition, ascorbate completely reversed the inhibition of shoot formation by gibberellic acid in young callus, but was less effective in old callus.     

The dopamine system in rat brain areas in the early period following irradiation with superhigh doses]

In studying the main indices that characterize the neurochemical system of biosynthesis and degradation of a dopamine neuromediator, tyrosine hydroxylase-dopamine-monoamine oxidase, in different brain regions 5-6 min, 1 and 18 h after whole-body irradiation with high energy electrons (100 Gy) the authors have revealed a 25-40% inhibition of tyrosine hydroxylase and monoamine oxidase activity, and a 40% increase in the dopamine content of basal ganglia of the brain that control behavioural reactions of the organism. The neurochemical disturbances revealed are involved in the mechanisms of early transient incapacity after irradiation with superhigh doses.     

Karyotypic characteristics of the murine myeloma line sp2/0-Ag14

Using methods of G- and C-banding, a study was made of the karyotype of mouse myeloma cell line sp2/0-Ag14. The number of chromosomes varies from 58 to 65, the modal class being 61-62. 50 per cent of chromosomes are rearranged. Normal chromosomes 6, 12 and X were not detected in either examined cell of this line. Among the marker chromosomes there are an isochromosome (19/19), three dicentric markers and one marker with two interstitial C-bands. There is a specific marker t (12; 15) of mouse plasmacytomas in the karyotype sp2/0-Ag14. A possible association of specific translocations and segregations of the normal chromosomes with the phenotype of line sp2/0-Ag14 is discussed. The results obtained may be useful for cytogenetic analysis of hybridomas.     

Non-temperature related effects of osmotic pressure on inward sodium current in the membrane of isolated rat spinal ganglia neurons

The effects of osmotic pressure on inward sodium current during a change in temperature were investigated during experiments on isolated rat spinal ganglia neurons using techniques of intracellular perfusion and voltage clamping. It was found that the effect of osmotic pressure on the kinetic parameters of sodium current does not depend on temperature over a wide range of 8–40°C; the apparent values of activation energies for the activation and inactivation processes do not dependent on degree of osmolality. Overall findings would appear to indicate that the osmotic pressure effect is actually initiated by association with aqueous transmembrane flux. Opinions are expressed as to the location of the structures through which this aqueous flux passes and of the sodium channel gating mechanism, together which the molecular mechanisms of interaction between these two elements.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 18, No. 4, pp. 518–525, July–August, 1986.