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Young stellar objects (YSOs) are protostars that exhibit bipolar outflows fed by accretion disks. Theories of the transition between disk and outflow often involve a complex magnetic field structure thought to be created by the disk coiling field lines at the jet base; however, due to limited resolution, these theories cannot be confirmed with observation and thus may benefit from laboratory astrophysics studies. We create a dynamically similar laboratory system by driving a $\sim$1 MA current pulse with a 200 ns rise through a $\approx$2 mm-tall Al cylindrical wire array mounted to a three-dimensional (3-D)-printed, stainless steel scaffolding. This system creates a plasma that converges on the centre axis and ejects cm-scale bipolar outflows. Depending on the chosen 3-D-printed load path, the system may be designed to push the ablated plasma flow radially inwards or off-axis to make rotation. In this paper, we present results from the simplest iteration of the load which generates radially converging streams that launch non-rotating jets. The temperature, velocity and density of the radial inflows and axial outflows are characterized using interferometry, gated optical and ultraviolet imaging, and Thomson scattering diagnostics. We show that experimental measurements of the Reynolds number and sonic Mach number in three different stages of the experiment scale favourably to the observed properties of YSO jets with $Re\sim 10^5\unicode{x2013}10^9$ and $M\sim 1\unicode{x2013}10$, while our magnetic Reynolds number of $Re_M\sim 1\unicode{x2013}15$ indicates that the magnetic field diffuses out of our plasma over multiple hydrodynamical time scales. We compare our results with 3-D numerical simulations in the PERSEUS extended magnetohydrodynamics code.
Throughout their history, dictionaries have been understood as sources of authority, whether that authority has been claimed by their makers or imputed by their audiences. In English-language contexts, that authority has taken various guises – moral, colonial, and legal, among others. Such authority rests, in part, on the linking of words, word forms, and grammatical structures to judgments about speakers, communities, and social relations. While those judgments have largely been aligned with codifying and maintaining a perceived “standard,” dictionaries have been sites of resistance, too. This chapter explores both assertions of authority and resistance. Given the long history of dictionaries and their substantial variety, the chapter adopts a case-study-like approach. It uses examples to explore how dictionaries have on the one hand upheld the civic, cultural, and social order, and on the other celebrated the linguistic practices and lexical innovations of marginalized communities and stigmatized varieties.
Wireless power transfer (WPT) is an emerging technology with many promising applications where transmitting power via wired connections is undesirable. However, near-field WPT between magnetically coupled inductors is highly susceptible to positional changes, with power transfer efficiency (PTE) suffering if the coils are misaligned. To combat this effect, many position-independent, self-adaptive, inductive WPT schemes have been developed. Recent work indicates that it is possible to passively achieve high PTE across the operating range with nonlinear capacitors. In this work, the functionality of nonlinear WPT circuits is investigated, and fundamental design equations are derived and validated. A simplified design procedure is proposed for the position-independent self-adaptive WPT using nonlinear capacitors, wherein the ideal capacitance is extracted for each coupling factor. The efficacy of the method is demonstrated with an experimental circuit. Future work in this area is also proposed.
The Australian SKA Pathfinder (ASKAP) radio telescope has carried out a survey of the entire Southern Sky at 887.5 MHz. The wide area, high angular resolution, and broad bandwidth provided by the low-band Rapid ASKAP Continuum Survey (RACS-low) allow the production of a next-generation rotation measure (RM) grid across the entire Southern Sky. Here we introduce this project as Spectral and Polarisation in Cutouts of Extragalactic sources from RACS (SPICE-RACS). In our first data release, we image 30 RACS-low fields in Stokes I, Q, U at 25$^{\prime\prime}$ angular resolution, across 744–1032 MHz with 1 MHz spectral resolution. Using a bespoke, highly parallelised, software pipeline we are able to rapidly process wide-area spectro-polarimetric ASKAP observations. Notably, we use ‘postage stamp’ cutouts to assess the polarisation properties of 105912 radio components detected in total intensity. We find that our Stokes Q and U images have an rms noise of $\sim$80 $\unicode{x03BC}$Jy PSF$^{-1}$, and our correction for instrumental polarisation leakage allows us to characterise components with $\gtrsim$1% polarisation fraction over most of the field of view. We produce a broadband polarised radio component catalogue that contains 5818 RM measurements over an area of $\sim$1300 deg$^{2}$ with an average error in RM of $1.6^{+1.1}_{-1.0}$ rad m$^{-2}$, and an average linear polarisation fraction $3.4^{+3.0}_{-1.6}$ %. We determine this subset of components using the conditions that the polarised signal-to-noise ratio is $>$8, the polarisation fraction is above our estimated polarised leakage, and the Stokes I spectrum has a reliable model. Our catalogue provides an areal density of $4\pm2$ RMs deg$^{-2}$; an increase of $\sim$4 times over the previous state-of-the-art (Taylor, Stil, Sunstrum 2009, ApJ, 702, 1230). Meaning that, having used just 3% of the RACS-low sky area, we have produced the 3rd largest RM catalogue to date. This catalogue has broad applications for studying astrophysical magnetic fields; notably revealing remarkable structure in the Galactic RM sky. We will explore this Galactic structure in a follow-up paper. We will also apply the techniques described here to produce an all-Southern-sky RM catalogue from RACS observations. Finally, we make our catalogue, spectra, images, and processing pipeline publicly available.
The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.
The millennium that stretched approximately from the year 500 to the year 1500, and that we call the Middle Ages, is marked by a paradox. There was on the one hand an aversion among theologians to the idea of the new, and on the other the development of what are considered today often underestimated and highly innovative approaches in theological thought. The formula nihil innovetur nisi quod traditum est (be there no innovation beyond what has been handed down), which Cyprian (Epistola 74:1) discussed in the context of the rebaptism controversy, and which has been attributed to the Roman bishop Stephen I, became a set phrase during the period. The term ‘innovator’ was an insult, and innovations in theology were to be avoided, since they entailed the risk of deviating from the old, true doctrine.
Should a theological treatise like mine not begin with the Bible instead of with a history of concepts – after all, the Second Vatican Council demands that dogmatic theology ‘be so arranged’ that ‘biblical themes are proposed first of all’ (Optatam totius, No. 16)? According to the wish of the Council Fathers, scripture is to provide dogmatics with themes, and not vice versa, with the Council thereby criticizing the tendency to constrain and exploit the Bible for reasons of dogma. This was something that neo-scholasticism had done, for example, when it treated the Bible as a reservoir of dicta probantia, of statements proving the truth of dogmatic propositions. It threw in quotations from scripture where it was deemed they would help the argument. Franz Diekamp, the neo-Thomist already mentioned in the previous chapter, expresses this in almost disarming clarity when he states that because the magisterium is ‘the closest and most direct guide to the Catholic faith’ (regula proxima fidei), and the Bible, which always needs the ‘magisterium to safeguard and interpret it’, is only the regula remota fidei, reference to scripture is only of secondary importance in theology and could indeed be dispensed with completely (see Diekamp 1930: 64–65).
The tradition of theological thought, from which I have given some prominent examples, contains a treasure trove of theories of doctrinal development that is for the most part ignored today. Yet, at a time when the Catholic doctrine of faith is under unprecedented pressure to change, this trove could provide a number of things, both ‘new’ and ‘old’ (Matthew 13:52): old, because if it loses living contact with its tradition, then the Church would no longer be the Church; and new, because the Church is not simply a club of traditional costumes that can afford to gather dust in a museum, but has a mission that it serves, along with its dogma. The fundamental question faced by theories of doctrinal development concerns the relationship that the old (without which the Church would no longer have roots) has with the new (without which the Church can have no future).
Without clear concepts, every discussion is bound to remain vague. This is a trivial observation. However, it is difficult to determine what role the history of a concept plays in its definition, since, whereas every definition aims for the greatest possible clarity, investigating the history of a concept often relativizes (if not undermines) such clarity. We could use an intensional definition and identify all the properties of the objects to which the term dogma applies; or we could use an extensional definition and look at all the objects that fall under the definition of ‘dogma’. The result of doing so would at best be a synchronous clarity that nonetheless conceals a diachronic ambiguity arising from the fact that the concept of dogma has not always been used in the theological context in the same way that it is used today. This is true for most of our concepts, and this is again a trivial observation. But, when it comes to the concept of dogma, the insight is also revealing, since, in its narrowest sense, the concept denotes a final and ‘irreformable’ (Denzinger, No. 3074) doctrine, while at the same time being itself the result of processes of change. Looking at the history of concepts therefore complicates theological reflection, but also prevents us from falling into the trap of underestimating the complexity of its themes.
‘As fundamental, wide-ranging and diverse as the contribution of the patristic epoch was to the history of dogma, so little was the process of doctrinal development reflected upon in its possibilities and limits, its forms and laws. Practice preceded theory’ (Fiedrowicz 2010: 329). However, the temporal primacy of practice does not mean from today’s point of view that the theology of the early Church made no contribution to a theory of dogmatic development. On the contrary, what is true of the Biblical texts is just as true of the early Fathers: namely, that the issue of dogmatic development, which came to a head in the eighteenth and nineteenth century, was alien to both in the intensity with which the issue is raised in the modern period with its awareness of discontinuities and of the need to explain them. Nevertheless, patristic theologians were also faced with the challenge of combining their loyalty to the origins of their religion with the desire to do justice to their time. Maurice Wiles (1967: 19) distinguishes three motives that led the early Church ‘along the path of doctrinal development’: first, the apologetic desire when faced with the inquiries of opponents to present the Christian faith plausibly, comprehensibly and rationally; second, the conflict within Christianity with so-called heretics, which necessitated a more precise and sharper formulation of the Church’s doctrine of faith; and, third, ‘the natural desire of some Christians to think out and to think through the implications of their faith as deeply and as fully as possible’.
Although the election of Benedict XV brought to an end the intense phase of the so-called modernism crisis, the narrowing of discussion that an anti-modernist magisterium imposed on the Church far outlasted the pontificate of Pius X. Taking the form of the anti-modernist oath, which was not officially abolished until 1967, it shaped theological discussions until the Second Vatican Council. As a result, the respected theories of development of the nineteenth century, which were all apologetic in tendency (i.e. all wanted to defend the legitimacy of Catholic doctrine against the inquiries of a critical history of dogma that suspected dogma of radical discontinuity), could barely find their feet in the first half of the twentieth century. As a prototype of the theologian who fell from apologetics to heresy, and finally to excommunication, Alfred Loisy served as a negative example to everybody.
We should remind ourselves to begin with of the central claims made in the second chapter of this book, namely, that, with the emergence during the Enlightenment of an approach to Church doctrine that no longer saw itself as apologetic doxography, but as a history of dogma that took a critical stance towards creed, the theology of the nineteenth century faced the challenge of thinking through the unstable simultaneity of continuity and discontinuity in an unprecedentedly radical way. This chapter will deal with some attempts that were made in the nineteenth century: the so-called Tübingen School in the shape of Johann Sebastian Drey and Johann Adam Möhler; John Henry Newman, who, despite his public activity, remained a solitary player in Catholic theology; the neo-scholastic controversies surrounding the concept of tradition and the conclusio theologica; and Alfred Loisy, who was an important representative of a position denigrated as modernism.
In the new foreword to the 1965 edition of his novel Sword of Honour, Evelyn Waugh wrote: ‘On reading the book I realized that I had done something quite outside my original intention. I had written an obituary of the Roman Catholic Church in England as it had existed for many centuries. All the rites and most of the opinions here described are already obsolete. When I wrote Brideshead Revisited I was consciously writing an obituary of the doomed English upper class. It never occurred to me, writing Sword of Honour that the Church was susceptible to change. I was wrong and I have seen a superficial revolution in what then seemed permanent.’ These few lines – written by an artist who was also an authority – describe a problem better than the many pages of a writer who is certainly not an artist and perhaps not even an authority. Waugh sees change, senses decay, and thinks that he has written an obituary. If he is right, then this book is an obituary, too. But is he right?
This book opened with the words of Evelyn Waugh, to whom it had ‘never occurred’ that ‘the Church was susceptible to change’, too. When he did notice this change, he thought that he should write (or that he had written) an ‘obituary’ to the Church, as one does to a dearly beloved who has passed away. Does change therefore visit death on the Church and do theories of doctrinal development that deal with this change sound the death knell for this sacred institution?