Use ofEscherichia coli A.T.C.C. 9637 for the asymmetric hydrolysis of amino acid derivatives

Riassunto L'azione delle acilasi presenti nelle cellule diE. coli A.T.C.C. 9637 è stata studiata utilizzando diversi substrati. Si è così trovato che alcuni cloroacetil e fenilacetil amino acidi subiscono un'idrolisi asimmetrica.     

In Memoriam C. G. Jung

Ohne Zusammenfassung     

Interstrain variation of murine arylsulfatase C.

A method has been developed for the assay of arylsulfatase C in tissue extracts containing arylsulfatases A and B. Significant variation of enzyme activity was observed among 26 inbred murine strains. Activity differences were apparent at all stages evaluated between 1 and 70 days postnatal age. Arylsulfatase C from representative high- and low-activity strains exhibited similar Michaelis constants, temperature optima, pH optima, thermostabilities and inhibitor profiles.     

Zum 70. Geburtstag von C. G. Jung

Ohne Zusammenfassung     

Vitamin C and the immune response.

The inclusion of vitamin C in the drinking water of BALB/c mice was without effect on the humoral antibody response to sheep red blood cells and bacterial lipopolysaccharide. However, there was a significantly increased cell-mediated immune response as determined by increased T-lymphocyte responses to concanavalin A. This might suggest a mechanism, along with interferon enhancement, for the possible protection by vitamin C against some viral infections.     

Hans Reichenbach's and C.I. Lewis's Kantian philosophies of science

Recent work in the history of philosophy of science details the Kantianism of philosophers often thought opposed to one another, e.g., Hans Reichenbach, C.I. Lewis, Rudolf Carnap, and Thomas Kuhn. Historians of philosophy of science in the last two decades have been particularly interested in the Kantianism of Reichenbach, Carnap, and Kuhn, and more recently, of Lewis. While recent historical work focuses on recovering the threatened-to-be-forgotten Kantian themes of early twentieth-century philosophy of science, we should not elide the differences between the Kantian strands running throughout this work. In this paper, I disentangle a few of these strands in the work of Reichenbach and Lewis focusing especially on their theories of relativized, constitutive a priori principles in empirical knowledge. In particular, I highlight three related differences between Reichenbach and Lewis concerning their motivations in analyzing scientific knowledge and scientific practice, their differing conceptions of constitutivity, and their relativization of constitutive a priori principles. In light of these differences, I argue Lewis's Kantianism is more similar to Kuhn's Kantianism than Reichenbach's, and so might be of more contemporary relevance to social and practice-based approaches to the philosophy of science.     

T. C. Chamberlin,Climate Change,and Cosmogony

This paper examines the life and work of T. C. Chamberlin, a prominent glacial geologist who developed an interest in interdisciplinary earth science. His work on the geological agency of the atmosphere informed his understanding of climate change and other terrestrial phenomena and led him to propose a new theory of the formation of the Earth and the solar system.Chamberlin's graduate seminar at the University of Chicago in 1896 contained all the themes that informed his research programme over the next three decades. These included the carbon dioxide theory of climate change in its relationship to diastrophism and oceanic circulation, the role of water vapour feedbacks in the climate system, and the relationship between multiple glaciations, the climate system, and the formation of the planet.     

Aufruf des international council of scientific unions (I.C.S.U.)

Ohne Zusammenfassung     

Resolution of singularities of surfaces by P. Del Pezzo. A mathematical controversy with C. Segre

We examine in some detail a series of papers published by P. Del Pezzo and C. Segre on the resolution of singularities of algebraic surfaces, trying to point out the main ideas.In 1888 P. Del Pezzo published a proof of the resolution of singularities of algebraic surfaces using birational transformations. He introduced the notion of equisingularity of two surfaces at a point or along a curve. This notion is made specific in a paper of 1889. C. Segre in his famous paper on infinitely near multiple points on a surface published in 1896 shows that Del Pezzo's method does not always produce a smooth surface. During 1897 each author reasserts his point of view in several papers which contain interesting remarks, regardless of their increasingly polemic style.     

On the action of vitamin C on the neuromuscular junctions.

High concentrations of ascorbic acid produce complete blockage of the transmission of nervous stimuli on the isolated neuromuscular preparation of phrenic nerve-hemidiaphragm of the rat.     

GFA expression in aggregation cultures of rat C6 glioma.

Few C6 glioma cells synthesize the astroglia-specific GFA protein in monolayer culture. A uniform population of GFA-positive cells was obtained by aggregation C6 cells in suspension culture, as previously reported for C6 glioma maintained on sponge foam matrices. These results strongly suggest that cell-to-cell interactions promote GFA expression.     

Electronmicroscopic identification of type C particles in cultured murine neuroblastoma.

Monolayer of murine neuroblastoma were treated with dexamethasone and examined by electronmicroscopy. Most of the treated cells were morphologically differentiated and exhibited type C virus particles which were budding from the cell surface. This in vitro system may be of great value for exploring the oncogenic potential of the virus, and its possible role in cell differentiation.     

Intracellular localization of calcitonin in the C cells of the rat.

Specific localization of C cells at the electron microscope level was achieved by an indirect immunoperoxidase technique. The hormone is present in the electron dense granules. The presence of granules apparently devoid of calcitonin was also detected.     

Autobiography and ‘The Two Cultures’ in the novels of C. P. Snow

That C. P. Snow had first-hand experience both in science and writing was taken for granted in the years of controversy over ‘the two cultures’, but neither the quality of his experience nor the circumstances of his eventual adoption of a literary career was given close enough consideration. Snow's own statements on these two points are often misleading. Yet the autobiographical nature of his fiction throws significant light on the subject. An examination of the autobiographical elements in Snow's novels in the light of his conception of the novel raises the question of whether his shift from science to literature was exactly the result of a genuine choice and also reveals that the two cultures dichotomy is embedded in his personal experience.