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Sheared flows perpendicular to the magnetic field can be driven by the Reynolds stress or ion pressure gradient effects and can potentially influence the stability and turbulent saturation level of edge plasma modes. On the other hand, such flows are subject to the transverse Kelvin–Helmholtz (KH) instability. Here, the linear theory of KH instabilities is first addressed with an analytic model in the asymptotic limit of long wavelengths compared with the flow scale length. The analytic model treats sheared $\boldsymbol{E}\times \boldsymbol{B}$ flows, ion diamagnetism (including gyro-viscous terms), density gradients and parallel currents in a slab geometry, enabling a unified summary that encompasses and extends previous results. In particular, while ion diamagnetism, density gradients and parallel currents each individually reduce KH growth rates, the combined effect of density and ion pressure gradients is more complicated and partially counteracting. Secondly, the important role of realistic toroidal geometry is explored numerically using an invariant scaling analysis together with the 2DX eigenvalue code to examine KH modes in both closed and open field line regions. For a typical spherical torus magnetic geometry, it is found that KH modes are more unstable at, and just outside of, the separatrix as a result of the distribution of magnetic shear. Finally implications for reduced edge turbulence modelling codes are discussed.

The microquasar GX 339-4 experienced an outburst in 2010. We focus on observations that are quasi-simultaneous with those made by INTEGRAL and RXTE in March–April 2010 with radio, NIR, optical and UV data. X-ray transients are extreme systems, often harboring a black hole, known to emit throughout the whole electromagnetic spectrum in outburst. We studied the source evolution and correlated changes in all wavelengths. The bolometric flux increased from 0.8 to 2.9 × 10−8 erg cm−2 s−1 while the relative contribution of the hot medium decreased. The radio, NIR and optical emission from jets was detected and observed to fade as the source softened; reprocessing in the disc was strong at the end.

ES62, an immunomodulatory phosphorylcholine-containing glycoprotein secreted by the rodent filarial nematode Acanthocheilonema viteae, has previously been shown to be produced by L4 larvae and adult worms only. However, homologous sequences to ES62 have recently been found in L1 and L3 cDNA libraries of certain human filarial nematodes. Therefore, the various stages of A. viteae were re-examined and it was again found that only the post-L3 stages secreted ES62. Synthesis but not secretion by earlier stages was ruled out by examination of the protein content of whole worm extracts and by immunoelectron microscopy. However, examination by PCR of the mRNA for ES62 revealed that it was found in the L1 and L3 larvae. This may explain why homologous sequences to ES62 have been found in Brugia malayi and Onchocerca volvulus larval cDNA libraries. It also suggests that filarial nematodes, in general, may secrete ES62. To obtain evidence for this, we investigated production by Brugia pahangi, a close relation of B. malayi. We found that ES62 was indeed secreted but, as with A. viteae, only by the post-L3 stages, although again the mRNA for ES62 could be detected in the earlier stages. Overall our results suggest that production of ES62 is not species specific, that it is indeed stage specific, and that this may be due to post-transcriptional control of expression.

The Fourier method in control systems reduces the study of controllability/observability to the study of related exponential families. In this paper we present examples of such systems, specifically those for which we can prove that the related exponential families form a Riesz basis in corresponding appropriately defined Sobolev spaces. This makes it possible to choose ‘natural’ pairs of spaces: the state space observability space and the control space state space, depending on whether an observation or a control problem is studied, respectively, so that the observation and control operators are isomorphisms.

Those of us who grope around in the mists of classical antiquity often come upon objects that remind us of the world we live in. There are analogies, always dangerous. There are many of the same words, or so it seems: arts, science, rhetoric, thesis, history, encyclopaedia. But they do not mean what we are used to. There are even historical continuities, but these also tend to be illusory.

The paper is concerned with the determination of the degree of convergence of a sequence of linear operators connected with the Fourier series of a function of class Lp (p > 1) to that function and some inverse results in relating the convergence to the classes of functions. In certain cases one can obtain the saturation results too. In all cases Lp norm is used.

In Lucian's Symposium, one of the wedding guests is a philosopher and another is a grammatikos. The grammatikos provides a bad elegiac epithalamium; the philosopher, who is called Ion, improves the occasion with a speech in which he declares that pederasty offers the best way of life, and the system of communal wives, as recommended in Plato's Republic, is the next best thing.This fantasy, of course, tells us nothing about what went on at weddings. Lucian's main motive is literary parody, of Plutarch's Erotikos or something of the kind. But it may serve to recall something of which we have evidence enough in Greek rhetoric, namely the practice of delivering speeches of some literary pretention at high-class weddings. The educated classes of the cities of the eastern provinces evidently cherished this habit: a display of culture, as well as of wealth, was admired, and elaborate orations took their place, alongside abundance of food and wine, music and song, elaborately decorated bridal chambers and beds, as concomitants of a wedding that was to do both families credit. This is true of the period of the ‘Second Sophistic’, and of its fourth-century and early Byzantine continuations. How far the practice was common before, say, the Antonine age is much less clear.

Specimens of polycrystalline ice were experimentally deformed in plane strain at a temperature of –1°C, under a constant load and with shortening strains varying from 2 to 27%. The randomc-axis orientation of the initial ice aggregates changes continuously with increasing strain towards a steady-state, small-circle containing two maxima lying about the shortening direction. The ice microstructure is sequentially transformed from undeformed grains to smaller, irregular, deformed grains containing recrystallized grains. Grain growth then occurs forming a coarse interlocking-grain aggregate. These microstructural changes are attributed to solid-state processes occurring during deformation. The previously deformed specimens were then annealed without a load at –1°C. Annealing resulted in a substantial grain-size coarsening. However, noc-axis preferred-orientation difference developed between annealed and unannealed samples.

Anything one says about the Letters of Phalaris must be, in some sense, provisional. We have no critical text, and it is clear from the work of Tudeer that exploration of the manuscript tradition might well cast light on the origins and development of this mysterious collection, the most ambitious example of fictitious epistolography that survives from antiquity. But the literary problems are so teasing that even a provisional exploration may serve at least a protreptic purpose.

I am concerned in this paper with Plutarch's treatment of the story of Coriolanus, not with the historical truth of the legend or with its development before Plutarch's time. I start from the hypothesis that the Life is, in its essentials, a transposition into biographical form of the historical narrative in Dionysius of Halicarnassus, Roman Antiquities, Books V to VIII. This has long been the common view. It was held and defended by Hermann Peter, Mommsen, and Eduard Schwartz. A careful reading of the two texts side by side tempts me to call it certain, so exact and frequent are the echoes. It is at any rate probable enough to justify an attempt to follow out its consequences by treating the differences between Dionysius and Plutarch, in default of other evidence, as Plutarch's constructions, to be explained in terms of his literary purposes and methods. This is what I shall do in the main part of this paper. I preface the details, however, by a few more general considerations.

This of course was Renaissance enthusiasm. The fame and influence which Plutarch enjoyed in the days of the rediscovery of antiquity could not survive the revolutions in historical and scholarly attitudes that marked the nineteenth century. Instead of being thought of as a mirror of antiquity and of human nature, he became a ‘secondary authority’, to be used where the ‘primary sources’ failed, himself to be quarried by theQuellenforscherand left a ruin. The present neglect of theLivesin education is a consequence of this. And yet it should be obvious that, for the very historical purposes for which the book is now chiefly studied, it is misleading and dangerous to use what is plainly one of the most sophisticated products of ancient historiography without constant regard to the plans and purposes of its author. Fortunately, a good deal has been written, especially in the last twenty years, to redress the balance.

The first part of Plutarch's Alcibiades, down to the point at which preparations for Sicily begin (17.1), has only the roughest chronological framework. It is largely made up of anecdote and reflection, and the order seems to be determined mainly by literary considerations. Hence its special interest for the study of Plutarch's methods. Why is the material arranged as it is? And what, if any, is Plutarch's original contribution? These are dangerous questions—the first because it is human to claim the presence of design where there is really only accident, and the second because to answer it properly would require unattainable completeness in our knowledge of the sources. Nevertheless, it is perhaps worth making the attempt.

So Clerimont in Ben Jonson's The Silent Woman; and it is to be feared he speaks for many. Plutarch's miscellaneous works, commonly and perhaps unfortunately called Moralia, have never enjoyed the popularity of the Lives. Yet they have enormous interest. They are a collection of short works on all kinds of subjects, the record of a life devoted to learning and a heart both generous and devout. Without them we should not only have lost a mass of knowledge, we should also have a different impression of many of the moral, social, and religious attitudes of the ancient world. Besides, as Bernays told Wilamowitz and Wilamowitz told the world, you can't say ‘I know Greek’ until you have read them.

It is a common, and irritating, practice of Plutarch's to begin his prooemium with a comparison or a contrast. Perhaps the same move may be appropriate for an essay in the interpretation of an author to whom Professor Dodds, forty years ago, wrote one of the most charming and penetrating introductions. We might put it like this: to be in debt is indeed bad, dangerous and corrupting; but to acknowledge debts of learning and friendship in the manner this volume intends, is both καλόν and ἡδύ.De vitando aere alieno is a vigorous and lively discourse. Style and subject mark it as somewhat out of Plutarch's usual line. It raises a swarm of problems. Is it genuine? Is it complete? Does it reflect a real crisis? The preliminary to any answer to these, and similar, questions seems to me to be an analysis of the speech as it stands, an attempt to show its connections of thought. This is all I shall try to do here.The thesis ὅτι οὐ δεῖ δανείζεσθαι involves two distinct propositions: that borrowing is a bad thing (A); and that there are ways of avoiding it (B). To look at it in this way brings it into line with the moral failings that Plutarch discusses in treatises like πϵρὶ φιλοπλουτίας or πϵρὶ δυσωπίας where the principal heads of the subject are naturally the attack on the vice and the suggestions for cure. Now both these basic propositions readily admit amplification. Proposition A can be enlarged by any means that paints the picture in darker colours, for example by representing the debtor as a damned soul (828F, 830F) or as a drowning man (831D). Proposition B leads at once to the hackneyed topics of the renunciation of luxury and the true freedom of the self-sufficient life. Plutarch did, I think, conceive of his subject under these heads. Given his moral preoccupation, this was almost inevitable. And in fact he treats the two themes turn and turn about, and we can detect the passage from one to the other, even where it is masked by the syntactical structure

(1) 583 b = p. 478. 26 Sieveking (Plutarchi Moralia, iii, Leipzig, 1929) …is objectionable. Since Lysis is already dead, cannot here signify ‘beforehand’. Its only other appropriate significance would seem to be ‘publicly, openly’: but also enters into the compound, and can only bear the sense ‘secretly’, which would involve us in a contradiction. so far as I know, does not occur elsewhere: nearly always has the sense ‘give some indication of…’.