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This essay analyzes the historiography of the German attempts during the Second World War to develop and harness the economic and military applications of uranium fission as well as the postwar "politics of the past." This literature, which began immediately after the end of the war and continues to the present day, includes contributions from scientists, historians, journalists, playwrights, and other authors. The essay is divided into mostly chronological sections. [ABSTRACT FROM AUTHOR]

We prove that equivariant matrix factorization categories associated to henselian local hypersurface rings are idempotent complete, generalizing a result of Dyckerhoff in the non-equivariant case. [ABSTRACT FROM AUTHOR]

Reciprocity and negativity in social relationships are fundamental topics of social research rarely examined in sub‐Saharan Africa. Since the number and quality of relationships is associated with individual outcomes, these ties are particularly important in impoverished areas. We conducted a multi‐method study of the conditions associated with problematic networks and difficult people, including face‐to‐face surveys in Agbogbloshie (Accra, Ghana) and Kangemi (Nairobi, Kenya). While one quarter of all relationships were perceived to be difficult, results reveal significant differences between the two communities in terms of the composition of personal networks and the factors associated with difficulty at both relational and network levels of analysis. Kenyan networks are more difficult when there is an imbalance of assistance provided by the respondent (exploitation), while any imbalance (inequality) is problematic in Ghanaian networks. These findings underscore the importance of independent analyses of negative ties and difficult networks, contributing to a community‐based understanding of poverty in urban slums. [ABSTRACT FROM AUTHOR]

A pulsar dynamic spectrum is an inline digital hologram of the interstellar medium; it encodes information on the propagation paths by which signals have travelled from source to telescope. To decode the hologram, it is necessary to 'retrieve' the phases of the wavefield from intensity measurements, which directly gauge only the field modulus, by imposing additional constraints on the model. We present a new method for phase retrieval in the context of pulsar spectroscopy. Our method makes use of the Fast Iterative Shrinkage Thresholding Algorithm (FISTA) to obtain sparse models of the wavefield in a hierarchical approach with progressively increasing depth. Once the tail of the noise distribution is reached the hierarchy terminates with a final, unregularized optimization. The result is a fully dense model of the complex wavefield that permits the discovery of faint signals by appropriate averaging. We illustrate the performance of our method on synthetic test cases and on real data. Our algorithm, which we call H-FISTA, is implemented in the python programming language and is freely available. [ABSTRACT FROM AUTHOR]

Background: Wide‐ranging restrictions on social and educational activities were imposed in 2020 in response to the COVID‐19 pandemic. These likely influenced the population dynamics of the head louse. Close physical contact between human hosts is required for transmission of this ectoparasite. Method: Pre‐ and post‐pandemic internet interest in the head louse in the UK was compared using Google Trends data from March 2017 to March 2022 and modeling using the Meta Prophet package. The influence of school holidays and school attendance was also investigated. Results: There was a sharp decline in internet searching of the term "head louse" from March 2020 onwards coinciding with COVID‐19 restrictions, and a large difference between pre‐ and post‐pandemic search volumes. No influence of school holidays or attendance on internet searching on the head louse was found. Conclusion: The results suggest pandemic restrictions have had a large effect on head louse incidence. [ABSTRACT FROM AUTHOR]

Objective: To develop and internally validate a deep-learning algorithm from fetal ultrasound images for the diagnosis of cystic hygromas in the first trimester. Methods: All first trimester ultrasound scans with a diagnosis of a cystic hygroma between 11 and 14 weeks gestation at our tertiary care centre in Ontario, Canada were studied. Ultrasound scans with normal nuchal translucency were used as controls. The dataset was partitioned with 75% of images used for model training and 25% used for model validation. Images were analyzed using a DenseNet model and the accuracy of the trained model to correctly identify cases of cystic hygroma was assessed by calculating sensitivity, specificity, and the area under the receiver-operating characteristic (ROC) curve. Gradient class activation heat maps (Grad-CAM) were generated to assess model interpretability. Results: The dataset included 289 sagittal fetal ultrasound images;129 cystic hygroma cases and 160 normal NT controls. Overall model accuracy was 93% (95% CI: 88–98%), sensitivity 92% (95% CI: 79–100%), specificity 94% (95% CI: 91–96%), and the area under the ROC curve 0.94 (95% CI: 0.89–1.0). Grad-CAM heat maps demonstrated that the model predictions were driven primarily by the fetal posterior cervical area. Conclusions: Our findings demonstrate that deep-learning algorithms can achieve high accuracy in diagnostic interpretation of cystic hygroma in the first trimester, validated against expert clinical assessment. [ABSTRACT FROM AUTHOR]

We study the influence of a cosmological population of dense gas clouds on distant sources, with an emphasis on quasar optical variability. In addition to gravitational lensing, such clouds affect flux measurements via refraction in the neutral gas and via dust extinction, leading to a variety of possible light curves even in the low optical depth limit. We classify and illustrate the types of light curves that can arise. For sources as large as quasars, we show that gravitational lensing and extinction are the dominant effects, with gas refraction playing only a minor role. We find that clouds with mass |$\sim 10^{-4.5\pm 0.5}\, \mathrm{M}_\odot$| can reproduce the observed distribution of quasar variation amplitudes, but only if such clouds make up a large fraction of the closure density. In that case, there may also be substantial extinction of distant optical sources, which can, in principle, be constrained by data on 'standard candles' such as type Ia supernovae. Unfortunately, that extinction is essentially grey, even when the material opacity is strongly wavelength dependent, making it difficult to distinguish from the influence of the background geometry. We propose a novel statistical test of the origin of quasar variability, based on the angular structure of the variation timescale for a large number of quasars distributed all over the sky. If quasar variability is primarily due to nanolensing, then angular structure is expected to include a quadrupole term of amplitude |$\sim 5{{\ \rm per\ cent}}$|⁠ , which ought to be measurable with future data from the Gaia mission. [ABSTRACT FROM AUTHOR]

Molecular hydrogen normally has only weak, quadrupole transitions between its rovibrational states, but in a static electric field it acquires a dipole moment and a set of allowed transitions. Here we use published ab initio calculations of the static electrical response tensors of the H2 molecule to construct the perturbed rovibrational eigensystem and its ground state absorptions. We restrict attention to two simple field configurations that are relevant to condensed hydrogen molecules in the interstellar medium (ISM): a uniform electric field and the field of a pointlike charge. The energy eigenstates are mixtures of vibrational and angular momentum eigenstates so there are many transitions that satisfy the dipole selection rules. We find that mixing is strongest among the states with high vibrational excitation, leading to hundreds of absorption lines across the optical and near-infrared. These spectra are very different from that of the field-free molecule, so if they appeared in astronomical data they would be difficult to assign. Furthermore, in a condensed environment the excited states likely have short lifetimes to internal conversion, giving the absorption lines a diffuse appearance. We therefore suggest electrified H2 as a possible carrier of the diffuse interstellar bands (DIBs). We further argue that in principle it may be possible to account for all of the DIBs with this one carrier. However, despite electrification, the transitions are not very strong and a large column of condensed H2 would be required, making it difficult to reconcile this possibility with our current understanding of the ISM. [ABSTRACT FROM AUTHOR]

The tick-borne condition Lyme borreliosis, commonly known as Lyme Disease, is an emerging problem in the U.K. Thus media coverage highlighting clinical features and measures to prevent tick bites is welcome. How well does the news media provide this information? Here, reports from the British Public Service Broadcaster, the BBC, were examined. BBC coverage of Lyme Disease was classed depending on media type as 'television', 'radio' or 'web page'. Keywords related to symptoms and prevention techniques were recorded. Images of ticks or the characteristic EM rashes were also noted. More reports occurred in the spring and summer months than autumn and winter (Q2, 31.7%: Q3, 29.1%). Early diagnostic features such as a 'rash' (53.3%) and reference to tick bites (68.9%) were frequently mentioned. Other symptoms were well covered; including fever or 'flu-like' symptoms (43.6%), malaise (35.9%) and joint pain (43.6%). Less often mentioned were focal symptoms; including arthritis (8.7%) or facial palsy (6.7%). Prevention techniques were mentioned in 32% of all media reports, with tick removal (26.2%) and body checking (20.3%) being most often mentioned. Tick images were frequently provided (40.7%), but those of EM rashes less often (16.5%). Overall, coverage of early symptoms was high. However, symptoms indicative of later infection were less well covered. Increased use of EM images, and more appropriate tick images, could aid Lyme Disease identification amongst the general public. [ABSTRACT FROM AUTHOR]

Every year, high numbers of firefighters are injured at fire incidents. A primary cause of moderate to severe injury can be linked to the protective garments worn by firefighters and understanding the limits of these protective garments is crucial for their safety. It would be substantially advantageous to firefighter safety if their available safe escape time is included in building design. To do this, the heat protective performance of firefighter garments needs to be translated into a tenable time. In this study, the minimum Thermal Protective Performance (TPP) rating of firefighter garments was investigated and found to compare well to known firefighter environments. This TPP rating was then used to further process the heat flux results from a CFD based fire model to determine an available safe escape time for firefighters. The probability of firefighters being injured was required in this study. It was used to assess the accuracy of the fire model in estimating the critical heat flux required to prevent a safe available escape time. [ABSTRACT FROM AUTHOR]

Scabies is a pruritic skin condition transmitted by Sarcoptic mites. A moderately strong correlation was observed between scabies word usage frequency and data from Savin et al.[6] on the percentage of patients admitted with scabies to the Edinburgh Skin Dispensary (1896-1960) (rs = 0.44) and for the Edinburgh Royal Infirmary (1908-1960) (rs = 0.58). The sampling interval was divided by this amount to obtain the cycle length.[5] Figure 1a shows scabies word frequency usage in the British English corpus from 1800 to 2019. [Extracted from the article]

The subject here is the exhaustion of the liberal conception of democracy. In order to tackle that, one takes into account the events occurred in June 2013 in Brazil, when a series of expressive public demonstrations revealed the crisis of this democratic narrative. This crisis is, precisely, the research problem of this article. Tentatively, as a hypothesis, one argues that these June Journeys (how the demonstrations became known as), despite the plurality of their demands and possible interpretations, served to express a social dissatisfaction with a merely procedural and representative democracy that fails to take the plurality of social interests into account, resulting in a conservative political culture that shies away from public debate in the name of a governability based on a hostility to the public voices. In order to conduct this analysis, one uses the hypothetic-deductive method while centering on bibliographical sources. [ABSTRACT FROM AUTHOR]

Military service has been shown to affect individuals' criminal and deviant tendencies. Studies on military service and deviance, however, has generally focused on combat veterans, utilized cross-sectional data, and ignored the potentially differential impact of military service based on sociodemographic variations. Utilizing the Add Health data and multilevel growth curve modeling, this study intends to reveal (a) trajectories of deviance from adolescence through adulthood, (b) whether military service in young adulthood moderates these trajectories, and (c) whether any of these relationships change by race, gender, and parental education. Findings revealed that military service was associated with a reduction in rates of delinquency, aggressive behavior, and drug use over time, and these patterns did not change by sociodemographic differences. [ABSTRACT FROM AUTHOR]

• Bilateral facial weakness can be a presenting feature of myopathy including desminopathy. • Myoimaging can have high diagnostic sensitivity and specificity in myopathies, including desminopathy. • This case report highlights the phenotypic and genetic heterogeneity of desminopathies. A 63 year old male presented with a 20 year history of facial weakness and several years of nasal regurgitation and dysphonia. Examination revealed bilateral facial weakness with nasal speech. Serum creatine kinase was 918 U/L. Neurophysiological studies suggested a myopathy and biopsy of the left vastus lateralis showed serpentine basophilic inclusions in the sarcoplasm and strong oxidative enzyme activity suggesting mitochondria accumulation. The muscle MRI showed selective fatty replacement within semitendinosus, gastrocnemius and soleus indicative of a desminopathy. A heterozygous missense variant c.17C>G (p.Ser6Trp) was identified within DES , predicted to be pathogenic in silico and previously described in a family with distal limb weakness. There are no previous case reports of desminopathy presenting with facial weakness, to our knowledge. Diagnosis was suggested following myoimaging of clinically unaffected muscles. Our study highlights the importance of muscle MRI in the diagnostic evaluation of muscle disease and further expands the known phenotypic heterogeneity of desminopathies. [ABSTRACT FROM AUTHOR]

This paper offers a contrast between "content-first" course design, and "skills-first" course design. The traditional lecture format is a paradigmatic example of the former, by the later I mean courses that emphasize the sustained practice of skills integral to the discipline. Two arguments are offered for adopting, other things being equal, the skills-first design. One is the "content-plus" argument that the skills-first course design does a better job of promoting content acquisition than a content-first class. The second argument, the "skills-plus" argument, claims that a skills-first course design has the added value of better promoting philosophical skills as compared with a content-first course. [ABSTRACT FROM AUTHOR]

I argue that if we allow that Moore's Method, which involves taking an ordinary knowledge claim to support a substantive metaphysical conclusion, can be used to support Moore's proof an external world, then we should accept that Moore's Method can be used to support a variety of incompatible metaphysical conclusions. I shall refer to this as "the problem of many proofs". The problem of many proofs, I claim, stems from the theory-ladenness of perception. I shall argue further that this plethora of proofs for incompatible positions leads to a darker form of skepticism, one which maintains that each of the dogmatic views is probably false. We will conclude by considering various ways a Moorean might respond to these difficulties. [ABSTRACT FROM AUTHOR]

It has been claimed that the variability of field quasars resembles gravitational lensing by a large cosmological population of free-floating planets with mass |$\sim\!\! 10\ {\rm M}_{\oplus }$|⁠. However, Galactic photometric monitoring experiments, on the other hand, exclude a large population of such planetary-mass gravitational lenses. These apparently contradictory pieces of evidence can be reconciled if the objects under consideration have a mean column density that lies between the critical column densities for gravitational lensing in these two contexts. Dark matter in that form is known to be weakly collisional, so a core develops in galaxy halo density profiles, and a preferred model has already been established. Here, we consider what such a model implies for Q2237+0305, which is the best-studied example of a quasar that is strongly lensed by an intervening galaxy. We construct microlensing magnification maps appropriate to the four macro-images of the quasar – all of which are seen through the bulge of the galaxy. Each of these maps exhibits a caustic network arising from the stars, plus many small, isolated caustics arising from the free-floating 'planets' in the lens galaxy. The 'planets' have little influence on the magnification histograms but a large effect on the statistics of the magnification gradients. We compare our predictions to the published Optical Gravitational Lensing Experiment (OGLE) photometry of Q2237+0305 and find that these data are consistent with the presence of the hypothetical 'planets'. However, the evidence is relatively weak because the OGLE data set is not well suited to testing our predictions and requires low-pass filtering for this application. New data from a large, space-based telescope are desirable to address this issue. [ABSTRACT FROM AUTHOR]

Prospective developments in computer and nanotechnology suggest that there is some possibility—perhaps as early as this century—that we will have the technological means to attempt to duplicate people. For example, it has been speculated that the psychology of individuals might be emulated on a computer platform to create a personality duplicate—an "upload." Physical duplicates might be created by advanced nanobots tasked with creating molecule-for-molecule copies of individuals. Such possibilities are discussed in the philosophical literature as (putative) cases of "fission": one person "splitting" into two. Many philosophers, perhaps most, reject the idea of fission, appealing to some form of a "no-branching" condition to rule out such possibilities. I argue, to the contrary, that there are good moral reasons to think that any account of personal identity that does not permit fission is deeply problematic, especially in connection with theorizing about criminal punishment. I discuss and reject David Lewis' famous account of personal identity that invokes "multiple occupancy" to allow for branching. In contrast, I offer an account of personal identity that permits branching using the type/token distinction to help with such puzzling cases. [ABSTRACT FROM AUTHOR]

Background: Lanthipeptides belong to the ribosomally synthesized and post-translationally modified peptide group of natural products and have a variety of biological activities ranging from antibiotics to antinociceptives. These peptides are cyclized through thioether crosslinks and can bear other secondary post-translational modifications. While lanthipeptide biosynthetic gene clusters can be identified by the presence of genes encoding characteristic enzymes involved in the post-translational modification process, locating the precursor peptides encoded within these clusters is challenging due to their short length and high sequence variability, which limits the high-throughput exploration of lanthipeptide biosynthesis. To address this challenge, we enhanced the predictive capabilities of Rapid ORF Description & Evaluation Online (RODEO) to identify members of all four known classes of lanthipeptides. Results: Using RODEO, we mined over 100,000 bacterial and archaeal genomes in the RefSeq database. We identified nearly 8500 lanthipeptide precursor peptides. These precursor peptides were identified in a broad range of bacterial phyla as well as the Euryarchaeota phylum of archaea. Bacteroidetes were found to encode a large number of these biosynthetic gene clusters, despite making up a relatively small portion of the genomes in this dataset. A number of these precursor peptides are similar to those of previously characterized lanthipeptides, but even more were not, including potential antibiotics. One such new antimicrobial lanthipeptide was purified and characterized. Additionally, examination of the biosynthetic gene clusters revealed that enzymes installing secondary post-translational modifications are more widespread than initially thought. Conclusion: Lanthipeptide biosynthetic gene clusters are more widely distributed and the precursor peptides encoded within these clusters are more diverse than previously appreciated, demonstrating that the lanthipeptide sequence-function space remains largely underexplored. [ABSTRACT FROM AUTHOR]