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Comprising fifteen books and over two hundred and fifty myths, Ovid's Metamorphoses is one of the longest extant Latin poems from the ancient world and one of the most influential works in Western culture. It is an epic on desire and transgression that became a gateway to the entire world of pagan mythology and visual imagination. This, the first complete commentary in English, covers all aspects of the text – from textual interpretation to poetics, imagination, and ideology – and will be useful as a teaching aid and an orientation for those who are interested in the text and its reception. Historically, the poem's audience includes readers interested in opera and ballet, psychology and sexuality, myth and painting, feminism and posthumanism, vegetarianism and metempsychosis (to name just a few outside the area of Classical Studies).
We compared optimal antibiotic prescribing before and after implementing an interpretive β-lactamase microbiology comment for Haemophilus influenzae and Moraxella catarrhalis in lower respiratory-tract infections. The postintervention group was associated with 5-fold increased odds of optimal de-escalation (adjusted odds ratio, 5.03; 95% confidence interval, 2.57–9.87).
Research demonstrates that children receive twice as much medical radiation from Computed Tomography (CT) scans performed at non-pediatric facilities as equivalent CTs performed at pediatric trauma centers (PTCs). In 2014, AFMC outreach staff educated Emergency Department (ED) staff on appropriate CT imaging utilization to reduce unnecessary medical radiation exposure. We set out to determine the educational campaign’s impact on injured children received radiation dose.
All injured children who underwent CT imaging and were transferred to a Level I PTC during 2010 to 2013 (pre-campaign) and 2015 (post-campaign) were reviewed. Patient demographics, mode of transportation, ED length of stay, scanned body region, injury severity score, and trauma center level were analyzed. Median effective radiation dose (ERD) controlled for each variable, pre-campaign and post-campaign, was compared using Wilcoxon rank sum test.
Three hundred eighty-five children under 17 years were transferred from 45 and 48 hospitals, pre- and post-campaign. Most (43%) transferring hospitals were urban or critical access hospitals (30%). Pre- and post-campaign patient demographics were similar. We analyzed 482 and 398 CT scans pre- and post-campaign. Overall, median ERD significantly decreased from 3.80 to 2.80. Abdominal CT scan ERD declined significantly from 7.2 to 4.13 (P-value 0.03). Head CT scan ERD declined from 3.27 to 2.45 (P-value < 0.0001).
A statewide, CT scan educational campaign contributed to ERD decline (lower dose scans and fewer repeat scans) among transferred injured children seen at PTCs. State-level interventions are feasible and can be effective in changing radiology provider practices.
The coronavirus disease 2019 (COVID-19) pandemic has led to global shortages of N95 respirators. Reprocessing of used N95 respirators may provide a higher filtration crisis alternative, but whether effective sterilization can be achieved for a virus without impairing respirator function remains unknown. We evaluated the viricidal efficacy of Bioquell vaporized hydrogen peroxide (VHP) on contaminated N95 respirators and tested the particulate particle penetration and inhalation and exhalation resistance of respirators after multiple cycles of VHP.
For this study, 3M 1870 N95 respirators were contaminated with 3 aerosolized bacteriophages: T1, T7, and Pseudomonas phage phi-6 followed by 1 cycle of VHP decontamination using a BQ-50 system. Additionally, new and unused respirators were sent to an independent laboratory for particulate filter penetration testing and inhalation and exhalation resistance after 3 and 5 cycles of VHP.
A single VHP cycle resulted in complete eradication of bacteriophage from respirators (limit of detection 10 PFU). Respirators showed acceptable limits for inhalation/exhalation resistance after 3 and 5 cycles of VHP. Respirators demonstrated a filtration efficiency >99 % after 3 cycles, but filtration efficiency fell below 95% after 5 cycles of HPV.
Bioquell VHP demonstrated high viricidal activity for N95 respirators inoculated with aerosolized bacteriophages. Bioquell technology can be scaled for simultaneous decontamination of a large number of used but otherwise intact respirators. Reprocessing should be limited to 3 cycles due to concerns both about impact of clinical wear and tear on fit, and to decrement in filtration after 3 cycles.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together
programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
The Murchison Widefield Array (MWA) is an electronically steered low-frequency (<300 MHz) radio interferometer, with a ‘slew’ time less than 8 s. Low-frequency (∼100 MHz) radio telescopes are ideally suited for rapid response follow-up of transients due to their large field of view, the inverted spectrum of coherent emission, and the fact that the dispersion delay between a 1 GHz and 100 MHz pulse is on the order of 1–10 min for dispersion measures of 100–2000 pc/cm3. The MWA has previously been used to provide fast follow-up for transient events including gamma-ray bursts (GRBs), fast radio bursts (FRBs), and gravitational waves, using systems that respond to gamma-ray coordinates network packet-based notifications. We describe a system for automatically triggering MWA observations of such events, based on Virtual Observatory Event standard triggers, which is more flexible, capable, and accurate than previous systems. The system can respond to external multi-messenger triggers, which makes it well-suited to searching for prompt coherent radio emission from GRBs, the study of FRBs and gravitational waves, single pulse studies of pulsars, and rapid follow-up of high-energy superflares from flare stars. The new triggering system has the capability to trigger observations in both the regular correlator mode (limited to ≥0.5 s integrations) and using the Voltage Capture System (VCS, 0.1 ms integration) of the MWA and represents a new mode of operation for the MWA. The upgraded standard correlator triggering capability has been in use since MWA observing semester 2018B (July–Dec 2018), and the VCS and buffered mode triggers will become available for observing in a future semester.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The conscientious commentator will offer his work to the public in a mood of doubt and self-questioning. As an Editor of the series in which this edition appears I have felt a special duty to keep in the forefront of my mind its declared aim: ‘to provide the student with the guidance that he needs for the interpretation and understanding of the book as a work of literature’. The amount of guidance here provided may, however, strike some readers as excessive. If so, it is because it has seemed to me that in the past Lucretius’ interpreters have not always taken enough pains to disentangle and follow his argument as he intended it to be followed, and this, whatever shortcomings may be found in the execution, is what I have attempted to do. The De Rerum Natura, in spite of the lucid style of which the poet was rightly proud, is a difficult book, and I have often preferred the risk of telling the reader what he already knows to that of leaving him in the lurch – the besetting sin of commentators. It may also be felt that there is here too much expatiation on the poetical techniques of Lucretius. In this department the existing commentaries seem to leave much to be desired. In spite of the lead given by H. Sykes Davies in his Criterion article of 1931–2 and in spite of more recent contributions in this field such as Professor David West’s excellent The imagery and poetry of Lucretius (1969), the conventional idea of Lucretius’ art still persists: ingenio maximus, arte rudis. Cicero knew otherwise; but posterity has yet to be convinced. The student who finds some notes inordinately long may care to note that an effort has been made to, so to say, ‘grade’ their contents so that the essential information is usually presented at the beginning.
Two considerations have prompted the thought that a second edition of this book may not be unwelcome. As informed interest in Lucretius has continued to grow – a fact strikingly illustrated by the number of translations that continue to appear – so it must be accepted that students now come to him less well prepared linguistically than was the case in the 1970s. Accordingly the Commentary has been extensively revised and enlarged, with, it is hoped, due account taken of the comments of reviewers – though my old friend and critic Professor David West would now miss in the notes the ‘brevity that comes close to wit’ that he admired in the first edition.
Three passages in the Introduction to the first edition have called for reconsideration: what was said there about the ‘middle’ or ‘florid’ style of oratory, the discussion of the diatribe and what is said about the spelling of seorsum. These points are dealt with at p. 13 n. 51, p. 14 n. 55 and p. 18 n. 73 respectively. The section on the text has been rewritten in the light of subsequent work in that field, especially that of Professor Michael Reeve and Dr David Butterfield, to both of whom I am greatly indebted for help and advice generously given. The apparatus criticus has also been revised in accordance with Dr Butterfield’s advice. Otherwise the Introduction is reprinted unaltered apart from a handful of additions to the footnotes in addition to the three noted above, and adjustment of the references to the secondary literature in conformity with current series style. In the Supplementary Introduction I have confined myself for the most part to comments on such post-1971 contributions to Lucretian studies (some of which are in any case noticed in the revised Commentary) as seem likely to be useful to readers of this book of the De Rerum Natura. I regret that it has not been possible to include references to all the important work of Professor Ferguson Smith on the Oenoanda inscription.
Prooemium. Lucretius begins each book of the poem in the high ‘pathetic’ style (genus grande, amplum, acre (Kenney 2007: 93)); here and in Books i, v and vi, it takes the form of a panegyric on Epicurus (Introd. 10–11). Only here is he addressed in the second person. For a sensitive analysis of the verbal structure and imagery of these lines see Stokes 1975. L. may intend to suggest a contrast with the false revelations of mystery religions, also expressed through images of light and darkness (Richardson 1974: 26–9). Whereas initiates in those cults were sworn to silence about what they had seen, the revelation offered by Epicurus is freely displayed in his teaching and writings and in L.’s verse.
1-4 These opening lines are carefully structured to create and then fulfil expectation. The apostrophe announced by O is deferred by the intervening qui-clause and so gains in weight; the grammatical and rhetorical structure is articulated by the sequence of monosyllables o – qui – te, each beginning a verse. This simple structure (characteristic of L.’s technique: Kenney 1977b/1995: 29; 2007: 103–4) is complicated and enriched by anticipation and enjambment (extollere…potuisti, tuis…signis) and by ‘theme and variation’, sequor being expanded in what follows. As throughout the Prooemium and indeed the whole poem the emotional impact is reinforced by alliteration. The whole style and feeling of L.’s address to Epicurus is hymnic, implicitly anticipating the explicit identification of 5.8 deus ille fuit, deus. Cf. 9–10nn. O: this, the reading of OV, and not the humanist conjecture e, is certainly what L. wrote. The sonorous interjection matches the emotional tone of the passage better than the prosaic (indeed superfluous) preposition (Timpanaro 1960/1978) and imparts ‘an elevated note appropriate to prayer’ (N–H 364 on Hor. C. 1.32.13).