Glasgow time signals

From 1859 to 1864, both visual and audio one o’clock time signals operated in Glasgow. Although the University carried a remit to provide the city’s time, following convoluted processes of establishment, a local chronometer-maker operated a time ball for 4 years. Towards the end of the period, time guns were triggered by telegraph from the Royal Observatory Edinburgh. Both exercises caused aggravation for the University. For the ball, the Professor of Astronomy, John Pringle Nichol, failed to convince the City Council that the “drop” control should originate from the University’s Observatory. For the guns, Robert Grant, the newly appointed Astronomy Chair holder, was aggrieved by the Astronomer Royal for Scotland, Piazzi Smyth, appearing to operate above his station. Rather than having only a once per day reference, both projects were abandoned as the University laid a dedicated telegraph cable from its observatory to control many public clocks and additional clocks with large sweep fingers indicating exact time to the second

Wireworm Control using Fodder Rape and Mustard – evaluating the use of brassica green manures for the control of wireworm (Agriotes spp.) in organic crops

In a field experiment at ADAS Pwllpeiran in 2001, brassica green manures were grown for 6 weeks and dug in before planting King Edward potatoes, to see if they suppressed wireworm in the crop. There was a trend for potatoes grown after mustard to suffer less damage from both wireworms and slugs than potatoes grown after fodder rape or no green manure, but the differences were not significant. Further trials, with longer green manuring periods, are needed to establish if there is a benefit, and whether the breakdown products of brassica green manures are toxic to wireworms

AZEuS: An Adaptive Zone Eulerian Scheme for Computational MHD

A new adaptive mesh refinement (AMR) version of the ZEUS-3D astrophysical magnetohydrodynamical (MHD) fluid code, AZEuS, is described. The AMR module in AZEuS has been completely adapted to the staggered mesh that characterises the ZEUS family of codes, on which scalar quantities are zone-centred and vector components are face-centred. In addition, for applications using static grids, it is necessary to use higher-order interpolations for prolongation to minimise the errors caused by waves crossing from a grid of one resolution to another. Finally, solutions to test problems in 1-, 2-, and 3-dimensions in both Cartesian and spherical coordinates are presented.Comment: 52 pages, 17 figures; Accepted for publication in ApJ

Causation and melanoma classification

In this article, I begin by giving a brief history of melanoma causation. I then discuss the current manner in which malignant melanoma is classified. In general, these systems of classification do not take account of the manner of tumour causation. Instead, they are based on phenomenological features of the tumour, such as size, spread, and morphology. I go on to suggest that misclassification of melanoma is a major problem in clinical practice. I therefore outline an alternative means of classifying these tumours based on causal factors. By analogy with similar systems that have recently emerged for other cancers, I suggest that this causal classification is likely to be both workable and helpful, even in the absence of a full causalmechanistic understanding of the aetiology of the tumour

Combining Model Selection Procedures for Online Prediction

Here we give a technique for online prediction that uses different model selection principles (MSP's) at different times. The central idea is that each MSP in a class is associated with a collection of models for which it is best suited so that the the data can be used to choose an MSP. Then, the MSP chosen is used with the data to choose a model, and the parameters of the model are estimated so that predictions can be made. Depending on the degree of discrepancy between the predicted values and the actual outcomes one may update the parameters within a model, reuse the MSP to rechoose the model and estimate its parameters, or start all over again rechoosing the MSP. Our main formal result is a theorem which gives conditions under which our technique performs better than always using the same MSP. We also discuss circumstances under which dropping data points may lead to better predictions

Circumventing embryonic lethality with Lcmt1 deficiency: generation of hypomorphic Lcmt1 mice with reduced protein phosphatase 2A methyltransferase expression and defects in insulin signaling.

Protein phosphatase 2A (PP2A), the major serine/threonine phosphatase in eukaryotic cells, is a heterotrimeric protein composed of structural, catalytic, and targeting subunits. PP2A assembly is governed by a variety of mechanisms, one of which is carboxyl-terminal methylation of the catalytic subunit by the leucine carboxyl methyltransferase LCMT1. PP2A is nearly stoichiometrically methylated in the cytosol, and although some PP2A targeting subunits bind independently of methylation, this modification is required for the binding of others. To examine the role of this methylation reaction in mammalian tissues, we generated a mouse harboring a gene-trap cassette within intron 1 of Lcmt1. Due to splicing around the insertion, Lcmt1 transcript and LCMT1 protein levels were reduced but not eliminated. LCMT1 activity and methylation of PP2A were reduced in a coordinate fashion, suggesting that LCMT1 is the only PP2A methyltransferase. These mice exhibited an insulin-resistance phenotype, indicating a role for this methyltransferase in signaling in insulin-sensitive tissues. Tissues from these animals will be vital for the in vivo identification of methylation-sensitive substrates of PP2A and how they respond to differing physiological conditions

Discovery in Medicine

In this chapter, I discuss the discovery of McArdle disease. I then use two philosophical account of discovery – one by Thomas Kuhn, the other by Norwood Hanson – to argue against the idea that discovery is merely a psychological phenomenon