Miscellaneous Letters on Burma, 1755-1760, I, edited by Alexander Dalrymple and re-edited by Michael W. Charney

These letters, and in cases extracts of letters, were reproduced by Alexander Dalrymple in 1808, published in London under the title Oriental Repertory, by William Ballintine for the East India Company. Relevant portions of Dalrymple’s commentary to some letters have also been included. Edited by Michael W. Charney for the SOAS Bulletin of Burma Research

The Regulation of Herpes Simplex Virus Immediate Early Gene Expression

The experiments presented in this thesis deal with two aspects of the transcriptional control of herpes simplex virus type 1 (HSV-1) immediate early (IE) gene expression. Stimulation of the IE gene set is mediated by a protein component of the virion, Vmw65, whose gene has been mapped on the viral genome (Campbell et al, 1984). A specific DNA fragment, BamHI F, containing the entire coding and flanking sequences for Vmw65 has been sequenced using a bacteriophage M13 shot-gun cloning strategy and the dideoxy sequencing technology. The fragment is 8,055 base pairs in size. The mRNA for Vmw65 has been positioned precisely, by nuclease SI mapping. The predicted open reading frame for Vmw65 consists of 490 codons and translates to a protein of molecular weight 54,342. The protein would appear to have no outstanding physical characteristics, such as regions of extreme hydrophobicity or hydrophilicity, but has significantly more acidic residues than the average protein, especially towards the carboxy terminus. The 5' and 3' flanking sequences of the gene exhibit recognisable signals known to be involved in the regulation of transcription and termination of eukaryotic genes. A homologue to Vmw65 has been identified in the genome of varicella-zoster virus (VZV; A. J. Davison, personal communication). The proteins from the two viruses are highly conserved at the level of amino acid sequence and approximately colinear, although the VZV equivalent is 80 amino acids shorter than Vmw65 at the carboxy terminus. Three other genes can be detected in the sequence of BamHI F, consistent with the mRNA mapping of Hall et al (1982). The functions of the products of these genes are unknown. All three genes have homology to genes on the VZV genome at the level of amino acid sequence, but the degree of conservation is variable. The region of VZV which is analogous to the BamHI F fragment shows an identical arrangement of genes to HSV-1. The second aspect of IE gene control which has been investigated is the reported autoregulation of IE gene 3 expression by its product Vmw175. This is based on experiments which showed Vmw175 to be present in lower abundance at early and late times, when compared to IE times, and the observation that a temperature sensitive mutant in Vmw175 (tsK) overproduces IE gene products. The investigation involved the use of plasmid constructs in which the HSV-1 thymidine kinase (TK) was placed under the control of IE promoters. These plasmids were analysed for expression of TK activity after introduction into tissue culture cells, together with the cloned Vmw175 gene from wild type or tsK virus, by calcium-phosphate transfection. The results presented confirm that autoregulation does occur. Polypeptide Vmw175 is able to stimulate expression from the promoters of IE genes 2 and 4/5, but not from its own promoter. This finding suggests that autoregulation may occur indirectly via competitive exclusion of the IE gene 3 promoter from the transcription machinery at post-immediate early times. The reason why Vmw175 cannot activate its own promoter is unclear, however some evidence is presented implicating the enhancer region of IE gene 3. The observation that Vmw175 activates other IE promoters, presumably in an analogous manner to the activation of early and late gene expression, may provide an insight into the role of these IE gene products in the viral lytic cycle

Calculus on the Sierpinski Gasket I: Polynomials, Exponentials and Power Series

We study the analog of power series expansions on the Sierpinski gasket, for analysis based on the Kigami Laplacian. The analog of polynomials are multiharmonic functions, which have previously been studied in connection with Taylor approximations and splines. Here the main technical result is an estimate of the size of the monomials analogous to x^n/n!. We propose a definition of entire analytic functions as functions represented by power series whose coefficients satisfy exponential growth conditions that are stronger than what is required to guarantee uniform convergence. We present a characterization of these functions in terms of exponential growth conditions on powers of the Laplacian of the function. These entire analytic functions enjoy properties, such as rearrangement and unique determination by infinite jets, that one would expect. However, not all exponential functions (eigenfunctions of the Laplacian) are entire analytic, and also many other natural candidates, such as the heat kernel, do not belong to this class. Nevertheless, we are able to use spectral decimation to study exponentials, and in particular to create exponentially decaying functions for negative eigenvalues

A new rhynchocephalian from the late jurassic of Germany with a dentition that is unique amongst tetrapods.

Rhynchocephalians, the sister group of squamates (lizards and snakes), are only represented by the single genus Sphenodon today. This taxon is often considered to represent a very conservative lineage. However, rhynchocephalians were common during the late Triassic to latest Jurassic periods, but rapidly declined afterwards, which is generally attributed to their supposedly adaptive inferiority to squamates and/or Mesozoic mammals, which radiated at that time. New finds of Mesozoic rhynchocephalians can thus provide important new information on the evolutionary history of the group. A new fossil relative of Sphenodon from the latest Jurassic of southern Germany, Oenosaurus muehlheimensis gen. et sp. nov., presents a dentition that is unique amongst tetrapods. The dentition of this taxon consists of massive, continuously growing tooth plates, probably indicating a crushing dentition, thus representing a previously unknown trophic adaptation in rhynchocephalians. The evolution of the extraordinary dentition of Oenosaurus from the already highly specialized Zahnanlage generally present in derived rhynchocephalians demonstrates an unexpected evolutionary plasticity of these animals. Together with other lines of evidence, this seriously casts doubts on the assumption that rhynchocephalians are a conservative and adaptively inferior lineage. Furthermore, the new taxon underlines the high morphological and ecological diversity of rhynchocephalians in the latest Jurassic of Europe, just before the decline of this lineage on this continent. Thus, selection pressure by radiating squamates or Mesozoic mammals alone might not be sufficient to explain the demise of the clade in the Late Mesozoic, and climate change in the course of the fragmentation of the supercontinent of Pangaea might have played a major role

Semi-empirical dissipation source functions for ocean waves: Part I, definition, calibration and validation

New parameterizations for the spectra dissipation of wind-generated waves are proposed. The rates of dissipation have no predetermined spectral shapes and are functions of the wave spectrum and wind speed and direction, in a way consistent with observation of wave breaking and swell dissipation properties. Namely, the swell dissipation is nonlinear and proportional to the swell steepness, and dissipation due to wave breaking is non-zero only when a non-dimensional spectrum exceeds the threshold at which waves are observed to start breaking. An additional source of short wave dissipation due to long wave breaking is introduced to represent the dissipation of short waves due to longer breaking waves. Several degrees of freedom are introduced in the wave breaking and the wind-wave generation term of Janssen (J. Phys. Oceanogr. 1991). These parameterizations are combined and calibrated with the Discrete Interaction Approximation of Hasselmann et al. (J. Phys. Oceangr. 1985) for the nonlinear interactions. Parameters are adjusted to reproduce observed shapes of directional wave spectra, and the variability of spectral moments with wind speed and wave height. The wave energy balance is verified in a wide range of conditions and scales, from gentle swells to major hurricanes, from the global ocean to coastal settings. Wave height, peak and mean periods, and spectral data are validated using in situ and remote sensing data. Some systematic defects are still present, but the parameterizations yield the best overall results to date. Perspectives for further improvement are also given.Comment: revised version for Journal of Physical Oceanograph

Twin Imperial Disasters. The invasions of Khiva and Afghanistan in the Russian and British official mind, 1839–1842

This paper examines two linked cases of abortive Imperial expansion. The British invasion of Afghanistan and the Russian winter expedition to Khiva both took place in 1839, and both ended in disaster. These events were linked, not merely by coincidence, but by mutual reactions to intelligence received in Orenburg, St Petersburg, Calcutta, London, and Tehran. British and Russian officials shared similar fears about each other's ambitions in Central Asia, similar patterns of prejudice, arrogance and ignorance, and a similar sense of entitlement as the self-conscious agents of two ‘Great Powers’. By examining the decision-making process which preceded these twin cases of expansion, and the British and Russian attitudes to Central Asian rulers and informants, the paper provides not only a deeper understanding of what provoked these particular disasters, but also of the wider process of European imperial expansion in the early nineteenth century

John Latham’s cosmos and mid-century representation

The conceptual artist John Latham (1921 – 2006) is sometimes cast as disconnected to the currents of British visual culture. Latham’s idiosyncratic cosmology based upon time and events and incorporating human creativity rather than matter and energy is used to distinguish this disconnection. However, this paper argues that his work can be seen as closely related to that of other mid-century cultural producers who were engaged with alternative cosmic speculations, and part of a broader shift in the register of representation. Papers from the Latham digital archive help make this case

Searching for a Stochastic Background of Gravitational Waves with LIGO

The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed the fourth science run, S4, with significantly improved interferometer sensitivities with respect to previous runs. Using data acquired during this science run, we place a limit on the amplitude of a stochastic background of gravitational waves. For a frequency independent spectrum, the new limit is $\Omega_{\rm GW} < 6.5 \times 10^{-5}$. This is currently the most sensitive result in the frequency range 51-150 Hz, with a factor of 13 improvement over the previous LIGO result. We discuss complementarity of the new result with other constraints on a stochastic background of gravitational waves, and we investigate implications of the new result for different models of this background.Comment: 37 pages, 16 figure

An Inserted α/β Subdomain Shapes the Catalytic Pocket of Lactobacillus johnsonii Cinnamoyl Esterase

Microbial enzymes produced in the gastrointestinal tract are primarily responsible for the release and biochemical transformation of absorbable bioactive monophenols. In the present work we described the crystal structure of LJ0536, a serine cinnamoyl esterase produced by the probiotic bacterium Lactobacillus johnsonii N6.2.We crystallized LJ0536 in the apo form and in three substrate-bound complexes. The structure showed a canonical α/β fold characteristic of esterases, and the enzyme is dimeric. Two classical serine esterase motifs (GlyXSerXGly) can be recognized from the amino acid sequence, and the structure revealed that the catalytic triad of the enzyme is formed by Ser(106), His(225), and Asp(197), while the other motif is non-functional. In all substrate-bound complexes, the aromatic acyl group of the ester compound was bound in the deepest part of the catalytic pocket. The binding pocket also contained an unoccupied area that could accommodate larger ligands. The structure revealed a prominent inserted α/β subdomain of 54 amino acids, from which multiple contacts to the aromatic acyl groups of the substrates are made. Inserts of this size are seen in other esterases, but the secondary structure topology of this subdomain of LJ0536 is unique to this enzyme and its closest homolog (Est1E) in the Protein Databank.The binding mechanism characterized (involving the inserted α/β subdomain) clearly differentiates LJ0536 from enzymes with similar activity of a fungal origin. The structural features herein described together with the activity profile of LJ0536 suggest that this enzyme should be clustered in a new group of bacterial cinnamoyl esterases