The in vivo expression of the globin genes of theβ cistron in γ-,δ-, andδβ-thalassemia heterozygotes

There is considerable evidence suggesting that the switch from to and chain production after birth is due, in part, to silencing of the genes by stage-specific factors which bind to their promoters and to the competition from the adult ( and ) genes for a common enhancer element located in the locus control region. As a consequence one can expect that the increased Hb F production in adults with hereditary persistence of fetal hemoglobin or -thalassemia is directed mainly by -globin genes in cis to the deletion(s) responsible for these conditions. Here we review data on heterozygotes with -, -, or -thalassemia, who also had an^AT mutation, in cis or in trans, which was used as a marker of gene expression. The results show that a deletion affecting adult genes favors the expression of genes in cis, while the deletion of a single gene does not affect the expression of the gene in cis but leads to a faster switch postnatally.     

The use of benzylpenicillinacylase fromEscherichia coli in the resolution of some racemicβ-,γ-,δ- andɛ-amino-acids

Summary The enzymatic hydrolysis of N-phenylacetyl derivatives of racemic amino-acids having the chiral centre removed from the usual -position is examined. The reaction is found to have different degrees of stereoselectivity. In the case of -amino-acids and of -aminovaleric acid, both enantiomers can be obtained in good yields and high optical purity. S-directed stereochemical preference was found for all the substrates examined.     

On “the application of science to science itself:” chemistry,instruments, and the scientific labor process

The “Instrumental Revolution” in chemistry refers to a transitional period in the mid-20th century during which sophisticated instrumentation based on physical principles was introduced to solve chemical problems. Historical and philosophical reflection on whether the revolution was a scientific one has been dominated by general models of scientific revolution, in particular, those proposed by Thomas Kuhn, I. B. Cohen and Ian Hacking. In this article I propose that the Industrial Revolution is a useful model for understanding the transformation wrought by the increasingly important role of machines in chemical research. Drawing on Marx's analysis of that event, I argue that that the Instrumental Revolution bears a striking resemblance to the industrial one. I offer grounds for thinking that the resemblance is not fortuitous, but rather reflects a general pattern of development involving the mechanization of the labor process. It is suggested that the cognitive consequences of radical changes in the means of production, as exemplified in the Instrumental Revolution, warrant the consideration of whether the latter is an instance of a kind of revolution in science rather than a singular episode.     

Spanish Jesuits in the Philippines: Geophysical Research and Synergies between Science,Education and Trade, 1865–1898

In 1865, Spanish Jesuits founded the Manila Observatory, the earliest of the Far East centres devoted to typhoon and earthquake studies. Also on Philippine soil and under the direction of the Jesuits, in 1884 the Madrid government inaugurated the first Meteorological Service in the Spanish Kingdom, and most probably in the Far East. Nevertheless, these achievements not only went practically unnoticed in the historiography of science, but neither does the process of geophysical dissemination that unfolded fit in with the two types of transmitter of knowledge identified by historians in the missionary diffusion of the exact sciences in colonial contexts. Rather than regarding science as merely a stimulus to their functionary and missionary tasks, Spanish Jesuits used their overseas posting to produce and publish original research –– a feature that would place them within the typology of the ‘seeker’ rather than the ‘functionary’ (in stark contrast to what the standard typology sustains). This paper also analyses examples of synergies between science, education and trade, which denotes, inter alia, the existence of a broad and solid educational structure in the Manila Mission that sustained the strength of research enterprise.     

Mechanizing the astronomer's vision: On the role of photography in Swedish astronomy,c.1880–1914

The beginnings of photographic astronomy in Sweden are taken as a case study of the incorporation of a new scientific technology. The introduction of photography during the late nineteenth century profoundly changed the way astronomers worked. Observational material became more mobile; photographic plates could be examined at a later date or transported to another location. Photography was presented in a rhetorical language, making it a truly objective way of observing the sky. The new technology was developed at the leading observatories, and was imported into countries such as Sweden through a network of scientific communication.     

Discovery of the Missing Correspondence between Carl Friedrich Gauss and the Rev. Nevil Maskelyne (1802–5)

More than 30 years ago in Annals of Science, Dr. Eric Forbes of the University of Edinburgh published the correspondence between Carl Gauss and Great Britain's Astronomer Royal, Nevil Maskelyne. Five of the letters he listed as missing have now been discovered, along with two entirely new letters he was unaware of. Their nearly complete correspondence can now be read for the first time in 200 years.     

What's nu? A re-examination of Maxwell's ‘ratio-of-units’ argument,from the mechanical theory of the electromagnetic field to ‘On the elementary relations between electrical measurements’

This re-examination of the earliest version of Maxwell's most important argument for the electromagnetic theory of light—the equality between the speed of wave propagation in the electromagnetic ether and the ratio of electrostatic to electromagnetic measures of electrical quantity—establishes unforeseen connections between Maxwell's theoretical electrical metrology and his mechanical theory of the electromagnetic field. Electrical metrology was not neutral with respect to field-theoretic versus action-at-a-distance conceptions of electro-magnetic interaction. Mutual accommodation between these conceptions was reached by Maxwell on the British Association for the Advancement of Science (BAAS) Committee on Electrical Standards by exploiting the measurement of the medium parameters—electric inductive capacity and magnetic permeability—on an arbitrary scale. While he always worked within this constraint in developing the ‘ratio-of-units’ argument mathematically, I maintain that Maxwell came to conceive of the ratio ‘as a velocity’ by treating the medium parameters as physical quantities that could be measured absolutely, which was only possible via the correspondences between electrical and mechanical quantities established in the mechanical theory. I thereby correct two closely-related misconceptions of the ratio-of-units argument—the counterintuitive but widespread notion that the ratio is naturally a speed, and the supposition that Maxwell either inferred or proved this from its dimensional formula.     

On the production of 12α-hydroxysteroid dehydrogenase fromClostridium group P,strain C48-50 ATCC 29733

Summary The production of 12-hydroxysteroid dehydrogenase ofClostridium group P strain C48-50 was optimized when the organism was grown in the presence of 2% fructose and 0.1% dithiothreitol. It appears that an initial redox potential of less than –160 mV (achieved by autoclaving in the presence of dithiothreitol, dithioerythritol or cysteine) is important in the production of this enzyme.