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We present a re-discovery of G278.94+1.35a as possibly one of the largest known Galactic supernova remnants (SNRs) – that we name Diprotodon. While previously established as a Galactic SNR, Diprotodon is visible in our new Evolutionary Map of the Universe (EMU) and GaLactic and Extragalactic All-sky MWA (GLEAM) radio continuum images at an angular size of $3{{{{.\!^\circ}}}}33\times3{{{{.\!^\circ}}}}23$, much larger than previously measured. At the previously suggested distance of 2.7 kpc, this implies a diameter of 157$\times$152 pc. This size would qualify Diprotodon as the largest known SNR and pushes our estimates of SNR sizes to the upper limits. We investigate the environment in which the SNR is located and examine various scenarios that might explain such a large and relatively bright SNR appearance. We find that Diprotodon is most likely at a much closer distance of $\sim$1 kpc, implying its diameter is 58$\times$56 pc and it is in the radiative evolutionary phase. We also present a new Fermi-LAT data analysis that confirms the angular extent of the SNR in gamma rays. The origin of the high-energy emission remains somewhat puzzling, and the scenarios we explore reveal new puzzles, given this unexpected and unique observation of a seemingly evolved SNR having a hard GeV spectrum with no breaks. We explore both leptonic and hadronic scenarios, as well as the possibility that the high-energy emission arises from the leftover particle population of a historic pulsar wind nebula.
The diplobathrid camerate crinoid genus Monstrocrinus is morphologically reinterpreted on the basis of new finds from the upper Emsian (Lower Devonian) to lower Eifelian (Middle Devonian) of Germany (Rhenish Slate Mountains, North Rhine-Westphalia, and Rhineland-Palatinate). The most complete, new specimen has a long segment of column projecting outward from the basal concavity, which confirms that the Monstrocrinus crown was attached to a column as an adult. Thus, a free-living life mode of a passively rolling or drifting crinoid is refuted and Monstrocrinus is reinterpreted as an attached, stalked echinoderm. This finding is supported by re-examination of the historical type material. A column attachment with a central pentalobate axial canal was recognized for the first time in the calyx of the holotype of the type species Monstrocrinus securifer. The holotype of Monstrocrinus granosus is far more complete than previously thought. It is a partially disarticulated crown embedded together with an associated longer part of the column. The extraordinary spines on the calyx plates of Monstrocrinus can be divided into eight morphological types and into two superordinate categories: “Category A” is a physical part of the calyx plate, whereas “Category B” is an attachment onto the calyx plate. Taxonomically, M. aliformis from the upper Emsian of Spain is treated herein as a subjective junior synonym of M. securifer.
We report a case of hypoplastic left heart syndrome and with subsequent aortopathy and then found to have hereditary haemorrhagic telangiectasia/juvenile polyposis syndrome due to a germline SMAD4 pathologic variant. The patient’s staged palliation was complicated by the development of neoaortic aneurysms, arteriovenous malformations, and gastrointestinal bleeding thought to be secondary to Fontan circulation, but workup revealed a SMAD4 variant consistent with hereditary haemorrhagic telangiectasia/juvenile polyposis syndrome. This case underscores the importance of genetic modifiers in CHD, especially those with Fontan physiology.
Wortupaite (IMA2022–107) is a new hydrated magnesium nickel tellurite mineral with a zemannite-like structure, described from the Wortupa gold mine, South Australia, Australia. Wortupaite forms needles up to 25 μm in length, generally clustered and sometimes in blocky masses of shorter (10‒15 μm) crystals. Wortupaite is found growing on melonite, from which the component nickel and tellurium are derived, and is associated with calcite. The strongest powder diffraction lines are [dobsÅ(Iobs)(hkl)]: 8.059 (93) (100), 4.034 (92) (200), 2.832 (43) (211 and 121), 2.769 (100) (202) and 1.920 (45) (213 and 123). The empirical formula of wortupaite as determined by electron probe microanalysis is (Mg0.57Ni0.39Mn0.04)Σ1(Ni2+1.87Fe3+0.13)Σ2(Te4+O3)3⋅3H2O, simplified to the ideal formula of MgNi2+2(Te4+O3)3⋅3H2O with H2O content calculated from the crystal structure. The average crystal structure of wortupaite was determined by single-crystal X-ray diffraction with synchrotron radiation (R1 = 0.0558 for 100 independent reflections). Wortupaite is hexagonal, crystallising in the space group P63/m, with a = 9.2215(13) Å, c = 7.5150(15) Å, V = 553.43(19) Å3 and Z = 2. Wortupaite has a microporous structure, with the negatively charged zemannite-like framework formed by Te4+O3 trigonal pyramids and Ni2+O6 octahedra. For charge balance, Mg2+ and Ni2+ dominant sites are assumed to be located on central sites in the channels, coordinated by 6 H2O groups. An OW site was refined around the Mg2+ dominant site, but OW position(s) were not locatable around the Ni2+ dominant site. A discussion of the different models for crystallographic arrangement of channel species is provided, taking into account possible Fourier truncation effects. Unlike the other four minerals with zemannite-like structures which have a near 50% split of divalent and trivalent framework cations, wortupaite is the first natural phase to have only divalent cations in the framework sites.
This article presents texts recovered by post-processing of multispectral images from the fifth- or sixth-century underwriting of the palimpsest Codex Climaci Rescriptus. Texts identified include the Anonymous II Proemium to Aratus’ Phaenomena, parts of Eratosthenes’ Catasterisms, Aratus’ Phaenomena lines 71–4 and 282–99 and previously unknown text, including some of the earliest astronomical measurements to survive in any Greek manuscript. Codex Climaci Rescriptus also contains at least three astronomical drawings. These appear to form part of an illustrated manuscript, with considerable textual value not merely on the basis of its age but also of its readings. The manuscript undertexts show significant overlap with the Φ Edition, postulated as ancestor of the various Latin Aratea.
Shade coffee is a well-studied cultivation strategy that creates habitat for tropical birds while also maintaining agricultural yield. Although there is a general consensus that shade coffee is more “bird-friendly” than a sun coffee monoculture, little work has investigated the effects of specific shade tree species on insectivorous bird diversity. This study involved avian foraging observations, mist-netting data, temperature loggers, and arthropod sampling to investigate bottom-up effects of two shade tree taxa - native Cordia sp. and introduced Grevillea robusta - on insectivorous bird communities in central Kenya. Results indicate that foliage-dwelling arthropod abundance, and the richness and overall abundance of foraging birds were all higher on Cordia than on Grevillea. Furthermore, multivariate analyses of the bird community indicate a significant difference in community composition between the canopies of the two tree species, though the communities of birds using the coffee understorey under these shade trees were similar. In addition, both shade trees buffered temperatures in coffee, and temperatures under Cordia were marginally cooler than under Grevillea. These results suggest that native Cordia trees on East African shade coffee farms may be better at mitigating habitat loss and attracting insectivorous birds that could promote ecosystem services. Identifying differences in prey abundance and preferences in bird foraging behaviour not only fills basic gaps in our understanding of the ecology of East African coffee farms, it also aids in developing region-specific information to optimize functional diversity, ecosystem services, and the conservation of birds in agricultural landscapes.
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
Aims
To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
Method
Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
Results
Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
Conclusions
AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.
We provide an overview of the monetary policy failures that resulted in the 2007–2008 financial crisis and ensuing Great Recession, focusing on the United States. Before the crisis, monetary policy was too loose, which fueled the bubble. After the bubble burst, monetary policy became too tight, hindering the recovery. These failures are fundamentally due to the Federal Reserve’s discretionary monetary policy. Furthermore, the popular approach of “constrained discretion” is really just discretion. Hence, it is sensitive to all the usual problems with discretionary monetary policy. Only firm monetary rules, ones that actually bind, can maintain macroeconomic stability and prevent crises.
Orthodox monetary policy scholarship assumes that central bankers act to maximize the public welfare. If imperfect incentives enter the model, it is on the part of the public. We challenge this assumption. Monetary policymakers are just as prone to incentive problems, which cause them to act according to their own self-interest. Furthermore, the self-interest of policymakers is not always the same thing as the public welfare. The two diverge frequently, in fact. We survey the history of the Federal Reserve and show the numerous ways discretionary central bankers have been compromised. These incentive problems are an inherent feature of discretion. They can only be eliminated by embracing true monetary rules.
We analyze the information problems inherent in discretionary monetary policy. Discretionary central bankers confront immense informational burdens. Some of these are technical problems only, and can in principle be overcome. But there is also a genuine knowledge problem involved in discretionary monetary policy: reacting in real time to changes in the demand for money. This problem is unsolvable. It renders discretionary central banking systematically unlikely to achieve macroeconomic stability. In contrast, rules-based policy does not confront a knowledge problem.
We conclude by situating the theory and practice of monetary policy within liberal political economy more generally. As we have seen, there are significant tensions between existing monetary institutions (discretionary central banking) and liberal ideals. This has been made even clearer by the Federal Reserve’s response to COVID-19. In brief, the Fed is now engaging in not only monetary policy but fiscal policy as well. This represents an immense expansion in its mandate, one that poses serious challenges for general and predictable monetary policy. The way out of this mess is embracing a comparative institutions approach to monetary policy. We cannot be satisfied with technical refinements to existing models and data. We need to explore alternative monetary policy rules, ones that are effective at providing macroeconomic stability while also respecting the requirements of democracy.
At root, the problems with the Federal Reserve (and many other central banks) are institutional. The repeated recessions and crises in the era of the Fed show that we need a radical reimagination of the basic institutions of monetary policy. In this chapter, we survey the work of the three great classically liberal Nobel laureates of the twentieth century – James Buchanan, F. A. Hayek, and Milton Friedman – to show that each of them gave serious consideration to monetary-institutional fundamentals. Our focus is not on their particular conclusions, but on how they thought about the problems of monetary institutional design. This represents a very different style of scholarship than macroeconomists and monetary economists currently practice. Unless scholars engage the research projects of Buchanan, Hayek, and Friedman, research in monetary economics will not be of much help in achieving lasting macroeconomic stability.