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Classical Myth in Medieval Ireland
No full textFrom allusions to the Olympians in seventh-century glosses to twelfth- and thirteenth-century vernacular adaptations of the epics of Vergil, Lucan, and Statius, Irish authors creatively re-imagined Greco-Roman mythology throughout the Middle Ages. They developed many strategies for situating the Classical deities within medieval Christian historiography, but rarely did they downplay or eliminate them. Some of these strategies, as this study reveals, reflected wider medieval European trends in Classical reception and mythography, whilst others were strikingly original and paralleled the ways in which Irish authors imagined the supernatural beings of their own pre-Christian past.This book examines why Irish authors were interested in the history and mythology of the ancient Mediterranean, and how Classical polytheism influenced their ideas about their own pagan past. It explores the ways in which depictions of Irish Otherworldly characters both shaped and were shaped by the gods and supernatural figures of the Classical adaptations. Based on close readings of texts such as the Irish version of Lucan, In Cath Catharda, this book argues that Classical scholarship in medieval Ireland was closely tied to medieval ideas about salvation history. Ultimately, it concludes that medieval Irish authors and audiences applied the same interpretive tools used for biblical exegesis to characters and events from Greco-Roman mythology, history, and literature, and to the supernatural inhabitants of pre-Christian Ireland alike
C. D. Broad on precognitions and John William Dunne
No full textC. D. Broad developed three different accounts of time over the course of his career. Emily Thomas (2019) has recently argued that the shift from the first to the second of these was motivated by his engagement with the philosophy of Samuel Alexander. In this paper, I argue that the shift from the second to the third was instigated by Broad’s engagement with precognitive dreams and with the thought of John William Dunne. Furthermore, I argue that fully appreciating Broad’s interest in psychic research in general, and precognitions in particular, is required for understanding the theory of time he defended in the second volume of Examination of McTaggart’s Philosophy. I also argue that interpreting the Examination in light of Broad’s engagement with Dunne can help remove the inconsistencies in Broad’s third account
Same data, different analysts:variation in effect sizes due to analytical decisions in ecology and evolutionary biology
No full textAlthough variation in effect sizes and predicted values among studies of similar phenomena is inevitable, such variation far exceeds what might be produced by sampling error alone. One possible explanation for variation among results is differences among researchers in the decisions they make regarding statistical analyses. A growing array of studies has explored this analytical variability in different fields and has found substantial variability among results despite analysts having the same data and research question. Many of these studies have been in the social sciences, but one small “many analyst” study found similar variability in ecology. We expanded the scope of this prior work by implementing a large-scale empirical exploration of the variation in effect sizes and model predictions generated by the analytical decisions of different researchers in ecology and evolutionary biology. We used two unpublished datasets, one from evolutionary ecology (blue tit, Cyanistes caeruleus, to compare sibling number and nestling growth) and one from conservation ecology (Eucalyptus, to compare grass cover and tree seedling recruitment). The project leaders recruited 174 analyst teams, comprising 246 analysts, to investigate the answers to prespecified research questions. Analyses conducted by these teams yielded 141 usable effects (compatible with our meta-analyses and with all necessary information provided) for the blue tit dataset, and 85 usable effects for the Eucalyptus dataset. We found substantial heterogeneity among results for both datasets, although the patterns of variation differed between them. For the blue tit analyses, the average effect was convincingly negative, with less growth for nestlings living with more siblings, but there was near continuous variation in effect size from large negative effects to effects near zero, and even effects crossing the traditional threshold of statistical significance in the opposite direction. In contrast, the average relationship between grass cover and Eucalyptus seedling number was only slightly negative and not convincingly different from zero, and most effects ranged from weakly negative to weakly positive, with about a third of effects crossing the traditional threshold of significance in one direction or the other. However, there were also several striking outliers in the Eucalyptus dataset, with effects far from zero. For both datasets, we found substantial variation in the variable selection and random effects structures among analyses, as well as in the ratings of the analytical methods by peer reviewers, but we found no strong relationship between any of these and deviation from the meta-analytic mean. In other words, analyses with results that were far from the mean were no more or less likely to have dissimilar variable sets, use random effects in their models, or receive poor peer reviews than those analyses that found results that were close to the mean. The existence of substantial variability among analysis outcomes raises important questions about how ecologists and evolutionary biologists should interpret published results, and how they should conduct analyses in the future
[3+2] Cycloaddition to a chiral 5-methylene-1,3-dioxolan-4-one and pyrolysis of the spiro adducts
No full textThe [3+2] cycloaddition chemistry of (2S)-5-methylene-2-t-butyl-1,3-dioxolan-4-one, derived from lactic acid, has been examined and spiro adducts have been obtained with benzonitrile oxide, acetonitrile oxide, diazomethane and diphenyldiazomethane. The structure and absolute stereochemistry of the benzonitrile oxide adduct has been confirmed by X-ray diffraction and all the adducts have been fully characterised by 1H and 13C NMR. Attempted cycloaddition with a nitrile sulfide, a nitrile imine and azides failed. Pyrolysis results in a range of novel gas-phase reactions, with the nitrile oxide adducts giving pivalaldehyde, CO2, the nitrile and ketene, the diazomethane adduct losing only N2 to give a cyclopropane-fused dioxolanone, and the diphenylcyclopropane derived from diphenyldiazomethane giving mainly benzophenone in a sequence involving loss of pivalaldehyde and methyleneketene
Resisting terror:civil action and non-violent resistance to terrorism in Basque country
No full textThis book on civil action and nonviolent resistance to terrorism in Basque Country explains the impact of collective action on the decline and end of the separatist armed group ETA. It reflects on how activism by the peace movement helped to delegitimize in society the use of terrorism to achieve political goals by diffusing democratic and nonviolence norms. It explores how civil society actors created new discourses that challenged ETA’s political project. It describes how civil resistance to the armed group undermined the prestige of militants within the community and helped to limit the social reach of violent extremist narratives. It depicts the efforts by social movement organizations to protect the fabric of society from the effects of political violence. It details how peacebuilding efforts by civil society groups were instrumental in building pressure from ETA’s own political movement to leave the armed struggle behind and later facilitate ETA’s disarmament and disbandment. And it indicates how the findings from this study can be extrapolated to go beyond this case and inform terrorism studies, civil resistance, peace and conflict, and social movements scholarship more widely
Effect of numerical resolution on synthetic observables of simulated coronal loops
No full textIncreasingly realistic simulations of the corona are used to predict synthetic observables for instruments onboard both existing and upcoming heliophysics space missions. Synthetic observables play an important role in constraining coronal heating theories. Choosing the spatial resolution of numerical simulations involves a trade-off between accuracy and computational cost. Since the numerical resolution affects not only the scale of structures that can be resolved, but also thermodynamic quantities such as the average coronal density, it is important to quantify the effect on synthesized observables. Using 3D radiative magnetohydrodynamic simulations of coronal loops at three different grid spacings, from 60 km down to 12 km, we find that changes in numerical resolution lead to differences in thermodynamic quantities and stratification as well as dynamic behaviour. Higher grid resolution results in a more complex and dynamic atmosphere. The resolution affects the emission intensity as well as the velocity distribution, thereby affecting synthetic spectra derived from the simulation. The distribution of synthetic coronal loop strand sizes changes as more fine-scale structure is resolved. A number of parameters, however, seem to start to saturate from our chosen medium grid resolution on. Our study shows that while choosing a sufficiently high resolution matters when comparing forward-modelled observables with data from current and future space missions, for most purposes not much is gained by further increasing the resolution beyond a grid spacing of 24 km, which seems to be adequate for reproducing bulk loop properties and forward-modelled emission, representing a good trade-off between accuracy and computational resource
Molecular inventory of the environment of a young eruptive star:case study of the classical FU Orionis star V1057 Cyg
No full textContext. Studying accretion-driven episodic outbursts in young stellar objects (YSOs) is crucial for understanding the later stages of star and planet formation. FU Orionis-type objects (briefly, FUors) represent a small but rather central class of YSOs, whose outbursts are characterized by a rapid multi-magnitude increase in brightness at optical and near-infrared wavelengths. These outbursts may have a long-lasting influence on the chemistry and molecular inventory around eruptive young stars. However, no complete line survey in the millimeter wavelength range exists in the literature for more evolved (i.e., Class II) sources, in contrast to wide-band coverages at optical and near-infrared wavelengths.Aims. We carried out the first dedicated wide-band millimeter line survey toward the low-mass young eruptive star and classical FUor V1057 Cyg, which has the highest observed peak accretion rate among FUors. This source is known to have a molecular outflow, and it is associated with dense material. This makes it a good candidate for a search for molecular species.Methods. We performed a wide-band spectral line survey of V1057 Cyg with the IRAM 30 m telescope from ∼72 to ∼263 GHz (with a spatial resolution between ∼36″ and ∼10″), complemented by on-the-fly maps of selected molecules. We also recorded additional spectra around 219, 227, 291, and 344 GHz (with a spatial resolution between ∼30″ and ∼19″) with the APEX 12 m telescope. We conducted simple radiative transfer and population diagram analyses to derive the column densities and excitation temperatures. We constructed integrated-intensity maps of the emission from several molecular species, including those that reveal outflows. These maps and a 12CO (3–2) position-velocity diagram provide insight into the past outburst activity of the source.Results. We identified mainly simple C-, N-, O-, and S-bearing molecules, deuterated species, molecular ions, and complex organic molecules. Several molecular species (HCN, HC3N, and HNC) trace large-scale (∼2′) structures in the environment of V1057 Cyg with indications of small-scale fragmentation that remains unresolved by the single-dish data. The position-velocity diagram of 12CO shows concentrated knots, which may indicate past episodic outburst activity. We calculated the dynamical timescale of the outflow and found it to be on the order of a few ten thousand years (between 15 000 and 22 000 years), similar to other eruptive stars. This suggests that the outflow cannot result from the ongoing outburst alone, since the source has been in the current outburst for less than a century. The population diagrams for species such as CH3OH, H2CO, and HC3N indicate rotational temperatures that range from 8 K to 15 K and column densities that range from 1.4×1012 cm−2 to 2.8×1013 cm−2.Conclusions. With over 30 detected molecular species (including isotopologs), V1057 Cyg and its environment display a rich chemistry considering the more evolved state of this source compared to well-studied but younger (i.e., Class 0/I) FUors, e.g., V883 Ori. The results of our line survey show that V1057 Cyg is a good candidate for future interferometric observations aimed at resolving emission extents to constrain molecular freeze-out and to search for emission lines of water and additional complex organic molecules. Our observations highlight the potential of millimeter line surveys to characterize the chemistry of eruptive stars and their environments, including more evolved sources, and to complement optical and near-infrared studies in this way to improve current statistics of the molecular inventories of these objects.<br/
Novel method for the rapid establishment of antibiotic susceptibility profiles in bacterial strains linked to musculoskeletal infections using Scattered Light Integrated Collector technology
No full textBacterial antibiotic resistance is an important challenge that the healthcare system is continually battling and a major problem in the treatment of musculoskeletal infections such as periprosthetic joint infections. Current methods to identify infectious microbes and define susceptibility to antibiotics require two to ten days from isolation to the establishment of an antibiogram. This slow process limits advances in antimicrobial drug discovery and, in the clinical context, delays the delivery of targeted treatments, with potentially devastating outcomes for patients. With this in mind, we strived to establish a quicker and more sensitive method to deliver antibiotic susceptibility profiles of clinically relevant microbes using Scattered Light Integrated Collector (SLIC) technology. We established antibiotic panels to obtain an approximate identification of a wide variety of microbes linked to periprosthetic joint infections and determine their susceptibility to antibiotics. We challenged microbes isolated from patients with our tailored antibiotic panels and found that SLIC detects perturbations in bacterial growth accurately and reproducibly within minutes of culture. Indeed, we could show that SLIC can be used to measure the dose-dependent inhibitory or bacteriolytic activity of broad classes of antibiotics. Our panel design enabled us to establish a profile similar to an antibiogram for the tested bacteria within 90 min. Our method can provide information on the class of bacteria tested and potential treatment avenues in parallel. Our proof-of-principle experiments using isolated clinical strains of bacteria demonstrate that SLIC, together with our specifically designed antibiotic panels, could be used to rapidly provide information on the identity of an infecting microbe, such as those associated with periprosthetic joint infections, and guide physicians to prescribe targeted antibiotic treatment early-on. The constant emergence of resistant strains of bacteria pushes the pharmaceutical industry to develop further effective drugs. Our optimized method could significantly accelerate this work by characterizing the efficacy of new classes of compounds against bacterial viability within minutes, a timeframe far shorter than the current standards
<i>In-operando </i>investigation of Purcell effect on efficiency roll-off in top-emitting phosphorescent organic light emitting diodes
No full textEfficiency roll-off is a major issue for applications of organic light emitting diodes (OLEDs) that require high brightness. The underlying processes leading to efficiency roll-off in phosphorescent OLEDs include triplet-polaron (TPA) and triplet-triplet annihilation (TTA). Hence, decreasing the triplet exciton lifetime by enhancing radiative decay rates can be an effective method to manage efficiency roll-off in phosphorescent OLEDs. Here we use in-operando measurement to study the Purcell effect and engineer efficiency roll-off. By changing the cavity parameters and measuring electroluminescence (EL) and photoluminescence (PL) on operating devices, we find that devices with higher Purcell factor have a smaller efficiency roll-off, suggesting a route to improve the performance of OLEDs in high brightness applications