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Review of Jon Tetsuro Sumidaâs In Defence of Naval Supremacy: Finance, Technology and British Naval Policy, 1889-1914
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Keeping the Germans out of the straits: The five ottoman dreadnought thesis reconsidered
This article contests Sean McMeekinâs claims concerning Russian culpability for the First World War. McMeekin maintains that Ottoman rearmament, particularly the purchase of several battleships released onto the global arms market by South American states, threatened to create a situation where the Russian Black Sea Fleet would be outclassed by its Ottoman opposite number. Rather than waiting for this to happen, the tsarist regime chose to go to war. Yet, contrary to McMeekinâs claims, the Ottoman naval expansion never assumed threatening dimensions because the Porte was unable to purchase battleships from Chile or Argentina. As a result, it provided no incentive for Russia to go to war in 1914
The Royal Navy and the German Threat, 1901-1914
Attached is a final draft version of the 'Introduction' to Matthew Seligmann's book The Royal Navy and the German Threat, 1901-1914. Re-distributed with permission from Oxford University Press.When and why did the Royal Navy come to view the expansion of German maritime power as a threat to British maritime security? Contrary to current thinking, Matthew S. Seligmann argues that Germany emerged as a major threat at the outset of the twentieth century, not because of its growing battle fleet, but because the British Admiralty (rightly) believed that Germany's naval planners intended to arm their country's fast merchant vessels in wartime and send them out to attack British trade in the manner of the privateers of old. This threat to British seaborne commerce was so serious that the leadership of the Royal Navy spent twelve years trying to work out how best to counter it. Ever more elaborate measures were devised to this end. These included building 'fighting liners' to run down the German ones; devising a specialized warship, the battle cruiser, as a weapon of trade defence; attempting to change international law to prohibit the conversion of merchant vessels into warships on the high seas; establishing a global intelligence network to monitor German shipping movements; and, finally, the arming of British merchant vessels in self-defence.
The manner in which German schemes for commerce warfare drove British naval policy for over a decade before 1914 has not been recognized before. The Royal Navy and the German Threat illustrates a new and important aspect of British naval history
Directed Mutations Recode Mitochondrial Genes: From Regular to Stopless Genetic Codes
Mitochondrial genetic codes evolve as side effects of stop codon ambiguity: suppressor tRNAs with anticodons translating stops transform genetic codes to stopless genetic codes. This produces peptides from frames other than regular ORFs, potentially increasing protein numbers coded by single sequences. Previous descriptions of marine turtle Olive Ridley mitogenomes imply directed stop-depletion of noncoding +1 gene frames, stop-creation recodes regular ORFs to stopless genetic codes. In this analysis, directed stop codon depletion in usually noncoding gene frames of the spiraling whitefly Aleurodicus dispersusʌ mitogenome produces new ORFs, introduces stops in regular ORFs, and apparently increases coding redundancy between different gene frames. Directed stop codon mutations switch between peptides coded by regular and stopless genetic codes. This process seems opposite to directed stop creation in HIV ORFs within genomes of immunized elite HIV controllers. Unknown DNA replication/edition mechanisms probably direct stop creation/depletion beyond natural selection on stops. Switches between genetic codes regulate translation of different gene frames
Do anticodons of misacylated tRNAs preferentially mismatch codons coding for the misloaded amino acid?
<p>Abstract</p> <p>Background</p> <p>Accurate amino acid insertion during peptide elongation requires tRNAs loaded by cognate amino acids and that anticodons match codons. However, tRNA misloading does not necessarily cause misinsertions: misinsertion is avoided when anticodons mismatch codons coding for misloaded amino acids.</p> <p>Presentation of the hypothesis</p> <p>Occasional compensation of misacylation by codon-anticodon mismatch necessarily occurs. Putatively, occasional error compensation may be enhanced beyond the random combination of independent errors in tRNA loading and codon-anticodon interactions: tRNA misacylation might alter potentials for codon-anticodon mismatches, perhaps specifically increasing potentials for mismatching those codons coding for the misacylated non-cognate amino acid. This hypothetical phenomenon is called 'error coordination', in distinction from 'error compensation' that assumes independence between misacylation and mismatch.</p> <p>Testing the hypothesis</p> <p>Eventually, the hypothesis should be tested for each combination of amino acid misacylation and codon-anticodon mismatch, by comparing stabilities or frequencies of mismatched codon-anticodon duplexes formed by tRNAs loaded by their cognate amino acid with stabilities formed by that tRNA when misloaded with the amino acid coded by the mismatched codon. Competitive mismatching experiments between misloaded and correctly loaded tRNAs could also be useful, yet more sophisticated experiments.</p> <p>Implications of the hypothesis</p> <p>Detecting error coordination implies estimating error compensation, which also promotes protein synthesis accuracy. Hence even in the absence of evidence for error coordination, experiments would yield very useful insights into misacylation and mismatch processes. In case experiments consider post-transcriptional RNA modifications (especially at wobble positions), results on codon-anticodon mismatches would enable significant improvements and sophistications of secondary structure prediction softwares. Positive results would show that protein translation enhances accuracies of products, not of single steps in the production. Ancient translational machineries putatively optimized error coordination, especially before tRNA editing by tRNA synthetases evolved: few primitive, but functionally versatile tRNA species perhaps executed low accuracy translation. Systems artificially designed/selected for low complexity and high efficiency could make use of this property for anticodons with high levels of error compensation and coordination.</p
Undetected antisense tRNAs in mitochondrial genomes?
<p>Abstract</p> <p>Background</p> <p>The hypothesis that both mitochondrial (mt) complementary DNA strands of tRNA genes code for tRNAs (sense-antisense coding) is explored. This could explain why mt tRNA mutations are 6.5 times more frequently pathogenic than in other mt sequences. Antisense tRNA expression is plausible because tRNA punctuation signals mt sense RNA maturation: both sense and antisense tRNAs form secondary structures potentially signalling processing. Sense RNA maturation processes by default 11 antisense tRNAs neighbouring sense genes. If antisense tRNAs are expressed, processed antisense tRNAs should have adapted more for translational activity than unprocessed ones. Four tRNA properties are examined: antisense tRNA 5' and 3' end processing by sense RNA maturation and its accuracy, cloverleaf stability and misacylation potential.</p> <p>Results</p> <p>Processed antisense tRNAs align better with standard tRNA sequences with the same cognate than unprocessed antisense tRNAs, suggesting less misacylations. Misacylation increases with cloverleaf fragility and processing inaccuracy. Cloverleaf fragility, misacylation and processing accuracy of antisense tRNAs decrease with genome-wide usage of their predicted cognate amino acid.</p> <p>Conclusions</p> <p>These properties correlate as if they adaptively coevolved for translational activity by some antisense tRNAs, and to avoid such activity by other antisense tRNAs. Analyses also suggest previously unsuspected particularities of aminoacylation specificity in mt tRNAs: combinations of competition between tRNAs on tRNA synthetases with competition between tRNA synthetases on tRNAs determine specificities of tRNA amino acylations. The latter analyses show that alignment methods used to detect tRNA cognates yield relatively robust results, even when they apparently fail to detect the tRNA's cognate amino acid and indicate high misacylation potential.</p> <p>Reviewers</p> <p>This article was reviewed by Dr Juergen Brosius, Dr Anthony M Poole and Dr Andrei S Rodin (nominated by Dr Rob Knight).</p
Mutation Patterns Due to Converging Mitochondrial Replication and Transcription Increase Lifespan, and Cause Growth Rate-Longevity Tradeoffs
Replicational Mutation Gradients, Dipole Moments, Nearest Neighbour Effects and DNA Polymerase Gamma Fidelity in Human Mitochondrial Genomes
Antimonuments: Between Memory and Resistance
The essay presents a reflection upon the âantimonumentsâ phenomena that emerged at the end of the twentieth century as a way of dealing through art with State violence, as in the case of Nazism and the Latin American dictatorships. The text begins with an explanation of the mnemotechnics, that is, the old âart of memoryâ, that had Simonides of Ceos as its mythic father. It goes on presenting the contemporary âart of memoryâ under the sign of âantimonumentsâ. The article proposes to think of a ânew art of memoryâ based on the gesture of anti-monuments. The study shows and discusses the works of, among other artists, Jochen Gerz, Horst Hoheisel, Andreas Knitz, Marcelo Brodsky and Fulvia Molina
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