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We compared the cost-effectiveness (CE) of an active case-finding (ACF) programme for household contacts of tuberculosis (TB) cases enrolled in first-line treatment to routine passive case-finding (PCF) within an established national TB programme in Peru. Decision analysis was used to model detection of TB in household contacts through: (1) self-report of symptomatic cases for evaluation (PCF), (2) a provider-initiated ACF programme, (3) addition of an Xpert MTB/RIF diagnostic test for a single sputum sample from household contacts, and (4) all strategies combined. CE was calculated as the incremental cost-effectiveness ratio (ICER) in terms of US dollars per disability-adjusted life years (DALYs) averted. Compared to PCF alone, ACF for household contacts resulted in an ICER of $2155 per DALY averted. The addition of the Xpert MTB/RIF diagnostic test resulted in an ICER of $3275 per DALY averted within a PCF programme and $3399 per DALY averted when an ACF programme was included. Provider-initiated ACF of household contacts in an urban setting of Lima, Peru can be highly cost-effective, even including costs to seek out contacts and perform an Xpert/MTB RIF test. ACF including Xpert MTB/RIF was not cost-effective if TB cases detected had high rates of default from treatment or poor outcomes.
The Ross Sea polynya is one of the most productive regions in the Southern Ocean. However, limited access and high spatio-temporal variability of physical and biological processes limit the use of conventional oceanographic methods to measure early season primary productivity. High-resolution observations from two Seagliders provide insights into the timing of a bloom in the southern Ross Sea polynya in December 2010. Changes in chlorophyll and oxygen concentrations are used to assess bloom dynamics. Using a ratio of dissolved oxygen to carbon, net primary production is estimated over the duration of the bloom showing a sensitive balance between net autotrophy and heterotrophy. The two gliders, observing spatially distinct regions during the same period, found net community production rates of -0.9±0.7 and 0.7±0.4 g C m-2 d-1. The difference highlights the spatial variability of biological processes and is probably caused by observing different stages of the bloom. The challenge of obtaining accurate primary productivity estimates highlights the need for increased observational efforts, particularly focusing on subsurface processes not resolved using surface or remote observations. Without an increased observational effort and the involvement of emerging technologies, it will not be possible to determine the seasonal trophic balance of the Ross Sea polynya and quantify the shelf’s importance in carbon export.
Scholarly assessments of Chaucer's fabliaux seldom acknowledge that these tales are erotic as well as funny; even less frequently do such investigations delve into why fabliaux are a source of pleasure. As Tom Hanks and W. W. Allman note in their article ‘Rough Love: Notes toward an Erotics of The Canterbury Tales’, scholars seem ‘to have averted their gaze when Chaucer's characters leap into bed’. Allman and Hanks, as their title implies, study an erotics of violence, mostly of men doing violence to women, and they focus in particular on the Merchant's Tale and its ‘erotics of stabbing’. A more positive erotic reading of the Merchant's Tale appears in Andrew Taylor's 1996 essay ‘Reading the Dirty Bits’. Taylor notes the lingering gaze of another scholar, E. Talbot Donaldson, upon a description of young May's body:
Hir fresshe beautee and hir age tendre,
Hir myddel smal, hire armes longe and sklendre,
Hir wise governaunce, hir gentilesse,
Hir wommanly berynge, and hire sadnesse.
Donaldson writes, ‘the Spring of pretty young girls is a permanent thing, and that May in their personas will always warm the masculine heart’. Taylor suggests that pleasure taken in this description and in Donaldson's gloss of it is mimetic: ‘For the young college man to share Donaldson's and Chaucer's pleasure in May is to become, like them, a connoisseur of both good writing and pretty girls, a master of ironic detachment and well-modulated heterosexual desire’.
In her 2007 essay ‘“Wordy vnthur wede”: Clothing, Nakedness and the Erotic in some Romances of Medieval Britain’, Amanda Hopkins examines the interplay of clothing and nudity in creating erotic moments, noting the connection of eroticism with female aggression on the one hand, and the erotic link between female nudity and passivity on the other. Lancelot's encounter with Elaine at Corbyn in Malory's Morte Darthur is marked by erotic moments featuring female nudity that appear emblematic of the latter. The eroticism of the moment when Lancelot rescues the ‘dolerous lady’ (2.791) from the boiling water by taking her by the hand, ‘naked as a nedyll’ (2.792), depends both on her total nudity and her status as victim – that is to say that the moment is erotic not just because she is naked, but because that nudity is not of her own making. Later, when Elaine ‘skypped oute of her bedde all naked’ (2.795) and kneels at Lancelot's feet to beg for her life, both her nudity and her vulnerability work to produce an erotic effect. Certainly Lancelot quickly changes his mind and turns from threatening her to embracing her. Yet to view Elaine as completely passive is a mistake – at the least her passivity is manipulated and Lancelot's presence in her bed is the result of machinations in which Elaine plays a willing part.
In the late fifteenth-century Squire of Low Degree, the incompetent protagonist woos a Hungarian princess in a way that seems to subject the romance genre to derivative, almost parodic, excess. This excess, however, offers particular insight into the representation of wooing in Middle English romance more broadly. While many romance heroines assume their suitors will display knightly prowess to win their love, this princess seems so aware of the Squire's shortcomings that she explains to him precisely what he must do, focusing on the rather boy-scout-like logistics of riding ‘Over hylles and dales, and hye mountaines, / In wethers wete, both hayle and raynes’, and lodging ‘under a tre, / Among the beastes wyld and tame’. Reminiscent here of how a Sir Thopas might understand chivalry, the text continues its overzealous attempt to ape romance when the princess exhaustively details the accoutrements that she expects from a suitor (203–30), and it is equally unable to find the right register when she offers to bankroll his required adventures (251–5). The envious steward's attempts to ruin the Squire by exposing his amorous inclinations are predictable enough; the results, however, have been seen as uncharacteristic of romance, since the king does not object to the Squire courting his daughter, but rather instructs the steward:
George Ripley, in his apostrophic preface to God in the Compound of Alchemy, claims to have ‘renounced … fleshly lust’ and asks God to provide him (and, presumably, other worthy alchemists) with His ‘secret treasure’: ‘Shew us thy secrets and to us be bounteous’ (21.4). Throughout the Compound, Ripley guides readers away from worldly pleasures, urging them instead to focus their desires on God-granted alchemical secrets and ‘our stone of great delight’ (37.2). Likewise, Thomas Norton, in his prologue to the Ordinal of Alchemy, warns of avaricious would-be alchemists who ‘in fyre / Of brennyng couetise haue therto desire’ (27–8). Norton emphatically shuns ‘wordly werkis’ in favour of alchemical ‘connyng’, advising his reader to ‘sett fully his trust’ in God and ‘in connyng be fixid al his lust’ (509, 517, 535–6): ‘For above all erthlye thynge / I mooste desire & love connynge’ (2595–6). Desire or lust, in both the Compound and the Ordinal, is thus redirected from the physical body and material world toward the divinely inspired knowledge of the alchemical corpus. Moreover, as I will illustrate, Norton and Ripley both direct their reader to focus on the text's rhetorical structures in order to achieve desired alchemical objectives.
In her seminal 1980 essay Pouvoirs de l'horreur, Julia Kristeva identifies ‘the abject’ as the human reaction to a breakdown in meaning caused by the loss of distinction between the subject and the object, the interior and the exterior, or the self and the Other. Her classic example of a site of abjection is that of the human corpse, which although a continuation of the dead person's corporeal presence also becomes simultaneously a marker of his or her spiritual absence, and thus must be rejected or repressed, causing the subjective experience of ‘horror’. Kristeva argues that human rationality necessarily involves a series of such repressions, and that the association of the human with the unrepressed thus becomes a site of potential tension. ‘The abject confronts us’, she suggests, ‘with those fragile states where man strays on the territories of animal’. This borderland between the acceptable and the unacceptable thus becomes the site of the carnivalesque, the comedic and the socially transgressive, as attested by post-medieval writers from Rabelais to Bakhtin and beyond.
In the first decade of the sixteenth century, the abject was also a major concern for the poet William Dunbar, writing at the court of King James IV. Dunbar's poems are critically regarded as some of the most brilliant – and, frequently, the most offensive – writings produced in late medieval/ early modern Scotland. Many of his satirical pieces depict the court of James (who would later go on to lose his life at the disastrous Battle of Flodden) at play, simultaneously parodying and affirming the excesses of late medieval/Renaissance aristocratic culture.
Sir Thopas's resolution to forsake human women in order to seek out an elf-queen as his lover satirizes one of the most well-known romance motifs: the fairy mistress who offers herself to the human protagonist of the narrative. It is characteristic of this motif that, with relatively few exceptions, the fairy offers sexual intercourse to the hero without any demand for the commitment of marriage and without stipulating any directly connected negative consequences. The motif's origins are a good deal earlier than those of romance – it features in several early medieval Irish narratives – but it is with romance that the motif is most particularly associated. It is noticeable that this extramarital sex is generally not explicitly condemned in the romances. Of course, romance authors are not prone to sermonizing digressions, so this might be passed over as merely a reflex of the genre; however, condemnation need not be overtly stated to still be clear and, in this respect, romance differs markedly from fabliaux, the other genre which frequently portrays extra-marital sex.
As Roger Ascham famously observed, Malory's Morte Darthur is primarily concerned with ‘open manslaughter, and bold bawdry’. I would not disagree; in fact, I would say that these themes are not only dominant but are inextricably interwoven. Male sexuality, in Malory, is consistently portrayed as potentially violent and disruptive, dangerous not only to individuals but to the whole structure of society, and therefore in need of controlling measures. The medieval world did not, of course, often portray any form of sexuality positively. Sexual desire leads both men and women to sin: both directly in committing fornication, incest and adultery, and indirectly in committing treason or disregarding their duties. It could easily be assumed that this is a divide between the clergy on the one side, themselves compelled to live in celibacy and thus suspicious of sexual desire, and the more relaxed nobility and commons on the other, cheerfully ignoring the rules when it suited them. However, this is too simple a dichotomy. Malory himself, despite the bold bawdry, shares in the suspicion of unregulated desire, in his nostalgia for a chaster time,
nowadayes men can nat love sevennyght but they muste have all their desyres … But the olde love was nat so. for men and women coulde love togydirs seven yerys, and no lycoures lustis was betwyxte them, and than was love trouthe and faythefulnes.
It is often said that the past is a foreign country where they do things differently, and perhaps no type of "doing" is more fascinating than sexual desires and behaviours. Our modern view of medieval sexuality is characterised bya polarising dichotomy between the swooning love-struck knights and ladies of romance on one hand, and the darkly imagined and misogyny of an unenlightened "medieval" sexuality on the other. British medieval sexual culture also exhibits such dualities through the influential paradigms of sinner or saint, virgin or whore, and protector or defiler of women. However, such sexual identities are rarely coherent or stable, and it is in the grey areas, the interstices between normative modes of sexuality, that we find the most compelling instances of erotic frisson and sexual expression. This collection of essays brings together a wide-ranging discussion of the sexual possibilitiesand fantasies of medieval Britain as they manifest themselves in the literature of the period. Taking as their matter texts and authors as diverse as Chaucer, Gower, Dunbar, Malory, alchemical treatises, and romances, the contributions reveal a surprising variety of attitudes, strategies and sexual subject positions. Contributors: Aisling Byrne, Anna Caughey, Kristina Hildebrand, Amy S. Kaufman, Yvette Kisor, Megan G. Leitch, Cynthea Masson, Hannah Priest, Samantha J. Rayner, Robert Allen Rouse, Cory James Rushton, Amy N. Vines.
As already mentioned in earlier chapters, the eikonal approximation can become invalid in local regions of the plasma. The most common problems are caustics (see Chapter 5), tunneling, and mode conversion. Both tunneling and mode conversion are processes where one incoming ray splits into two outgoing rays, a transmitted ray and a converted ray. The matched asymptotic methods are therefore more complicated than for caustics. Tunneling concerns only one eigenvalue of the N × N dispersion matrix, while mode conversion entails two. It follows that tunneling involves only one polarization, while mode conversion is associated with a pair. Therefore, tunneling can be reduced by Galerkin projection locally to a scalar formulation, while mode conversion is inherently a vector problem. An important point we should emphasize is the following: For caustics, it is always possible to find a local representation where the eikonal approximation is valid. In contrast, in tunneling and mode conversion regions, there is no representation in which the eikonal approximation is valid. It is only when we consider points far from the conversion region that we recover eikonal behavior. This leads to two important questions:
If the eikonal approximation is not valid within the conversion region, why persist in using ray tracing there?
Although the eikonal approximation is valid for the incoming wave field (by assumption), what justifies the assumption that the transmitted and converted wave fields become eikonal once more?
This complete introduction to the use of modern ray tracing techniques in plasma physics describes the powerful mathematical methods generally applicable to vector wave equations in non-uniform media, and clearly demonstrates the application of these methods to simplify and solve important problems in plasma wave theory. Key analytical concepts are carefully introduced as needed, encouraging the development of a visual intuition for the underlying methodology, with more advanced mathematical concepts succinctly explained in the appendices, and supporting Matlab and Raycon code available online. Covering variational principles, covariant formulations, caustics, tunnelling, mode conversion, weak dissipation, wave emission from coherent sources, incoherent wave fields, and collective wave absorption and emission, all within an accessible framework using standard plasma physics notation, this is an invaluable resource for graduate students and researchers in plasma physics.