A different perspective on the vev insertion approximation for electroweak baryogenesis

In the vev insertion approximation (VIA) the spacetime dependent part of the mass matrix is treated as a perturbation. We calculate the source terms for baryogenesis expanding both the self-energy and propagator to first order in mass insertions, which gives the same results as the usual approach of calculating the self-energy at second order and using zeroth order propagators. This procedure shows explicitly the equivalence between including the mass in the free or in the interaction Lagrangian. The VIA source then originates from the same term in the kinetic equation as the semi-classical source, but at leading order in the derivative expansion (the expansion in diamond operators). On top, another type of derivative expansion is done, which we estimate to be valid for a bubble width larger than the inverse thermal width. This cuts off the divergence in the VIA source in the limit that the thermal width vanishes.

A Classical Source for Petrarch’s Conceit of the Binding Knot of Hair: Apuleius’s Metamorphoses

The conceit of the beloved’s hair ensnaring and binding the poet’s heart and soul is common in Renaissance poetry and particularly widespread in the tradition of Petrarchan love lyric. The topos can be traced back to Petrarch’s canzoniere, or Rerum vulgarium fragmenta, in which Laura’s golden hair is often described in terms of knots and laces tying both the poet’s heart and soul. No classical antecedent has previously been identified for the image. In this study, I propose a possible classical source for the characteristic Petrarchan motif of Laura’s binding hair knot: Apuleius’s Metamorphoses, a manuscript of which the poet owned and which he read and annotated several times. In particular, I show how passages such as Lucius’s celebration of the beauty of women’s hair (Metamorphoses, II.8–9), and especially his declaration of love to Photis, an oath he takes on ʻthat sweet knot of your hair with which you have bound my spiritʼ (ibid., III.23), can be convincingly regarded as a source for Petrarch’s conceit. In addition to the value inherent in the detection of a new source for an influential Petrarchan topos, the present study may have some further implications. It could offer novel arguments for the dating of a series of Petrarchan poems, and it could foster a potentially fruitful reappraisal of the influence of Apuleius’s work on Petrarch’s vernacular poetry.

Insect Chitin-Based Nanomaterials for Innovative Cosmetics and Cosmeceuticals

Chitin and its derivatives are attracting great interest in cosmetic and cosmeceutical fields, thanks to their antioxidant and antimicrobial properties, as well as their biocompatibility and biodegradability. The classical source of chitin, crustacean waste, is no longer sustainable and fungi, a possible alternative, have not been exploited at an industrial scale yet. On the contrary, the breeding of bioconverting insects, especially of the Diptera Hermetia illucens, is becoming increasingly popular worldwide. Therefore, their exoskeletons, consisting of chitin as a major component, represent a waste stream of facilities that could be exploited for many applications. Insect chitin, indeed, suggests its application in the same fields as the crustacean biopolymer, because of its comparable commercial characteristics. This review reports several cosmetic and cosmeceutical applications based on chitin and its derivatives. In this context, chitin nanofibers and nanofibrils, produced from crustacean waste, have proved to be excellent cosmeceutical active compounds and carriers of active ingredients in personal care. Consequently, the insect-based chitin, its derivatives and their complexes with hyaluronic acid and lignin, as well as with other chitin-derived compounds, may be considered a new appropriate potential polymer to be used in cosmetic and cosmeceutical fields.

The relation between quantum and classical field theory with a classical source

Classical field theory is about fields and how they behave in space–time. Quantum field theory, in practice, usually seems to be about particles and how they scatter. Nevertheless, classical fields must emerge from quantum field theory in appropriate limits, and Michael Duff showed how this happens for the Schwarzschild solution in perturbative quantum gravity. In a series of papers, we and others have shown how classical radiation from an accelerated charge emerges from quantum field theory when the Unruh thermal effect is taken into account. Here, we sharpen those conclusions by showing that, even at finite times, the quantum picture is meaningful and is in close agreement with the classical picture.

Behind the Facade of Uvarov’s Classicism: Career Strategies of Classical Philologists at Russian Universities

Introduction. The article is focused on reconstruction of the practices of forming a disciplinary group of classical philologists in the Russian Empire universities in the 1830s – 1850s. Methods. For this purpose, the archival materials of the Ministry of Education, as well as Saint Petersburg, Moscow, Kazan and Kiev Universities are considered. The research methodology is based on a combination of both traditional general historical methods and methods of classical source studies, and approaches developed in the framework of the history of science, the sociology of knowledge and the history of disciplines. Analysis and results. It is important to analyze three points: the political context, practices in building career trajectories and academic networks of professors of Greek and Roman literature and antiquities at Russian universities. The transformation of the existing network of universities into the system of public education was carried out by the Minister of Public Education Sergey Uvarov in the 1830s. Transferring to Russia the European model of secondary education based on the study of classical languages, Uvarov created a system of general education and relentlessly promoted antiquity studies in the Russian Empire. Teaching classical disciplines was expanded at gymnasiums and universities. Following the academic personnel reform of the late 1830s, a number of “antiquity chairs” at universities was headed by young philologists and historians who had spent two or three years of training at universities in Germany, mainly in Berlin, attending lectures and seminars of leading German classical philologists. In the 1840s – 1850s, an artificially constructed group of classical philologists gradually transformed into a disciplinary community.

The transition rates of an isotropic quantum charged oscillator in the presence of external fields

In this work, explicit expressions for the transition rates of an isotropic quantum charged harmonic oscillator in the vicinity of a perfectly conducting half-space under the influence of an external classical source are obtained. In the absence of external sources, it is shown that the decay rate of an initially exited state of the oscillator is a periodic function in terms of the normalized distance to the plate. The modified transition rates in the presence of external classical sources are obtained in the large-time limit indicating a contribution proportional to the squared module of the Fourier transform of the external source. In the absence of the conducting plate and external sources, the results are in agreement with the free space case. The problem is generalized to the case of a real conducting half-space.

“Become This Whole World”: The Phenomenology of Metaphysical Religion in Chāndogya Upaniṣad 6–8

Implicit in Heidegger’s 1920–1921 Phenomenology of Religious Life is an account of religion as a radical transformation of the very structures of experience. This article seeks to apply that account to a classical Indian discourse on reality and the self, Chāndogya Upaniṣad chapter six. This classical source-text for two thousand years of Hindu theology advocates a new ‘religious life’ achieved through phenomenologically reorienting the very structures of cognition toward the broadest truths of reality, rather than the finite features of the world. The goal is to create a new form of primordial subjectivity with an altered relationship to phenomena, finitude, and the divine. The article proceeds in two parts: The first section brings out Heidegger’s theory of religion through a reading of Heidegger’s 1920 Phenomenology of Religious Life with the help of his lectures, On the Definition of Philosophy, from the previous year. The second section tries to demonstrate the value of integrating traditional textual/historical scholarship in the Chāndogya Upaniṣad with Heidegger’s method. The juxtaposition aims to both (1) foreground the phenomenologically transformative goals of this influential Indian text, and (2) challenge Heidegger’s scepticism about the religious value of metaphysical reflection.

Comparison of the bacterial and methanotrophic diversities between an Italian paddy field and its neighboring meadow

Methane is a potent greenhouse gas that contributes to global warming. However, under certain conditions, its release into the atmosphere can be mitigated by methane-oxidizing microorganisms. Typically, cultivated wetlands (i.e., paddy fields) are a major source of methane (CH4) while forests and meadow uplands are considered to be CH4 sinks. As the global need for rice production increases each year, more uplands are converted to inundated paddy fields. To investigate soils that may be converted into productive land for rice production, we investigated a paddy field and adjacent meadow in Northern Italy. Using a combination of 16S rRNA gene amplicon sequencing to analyze the bacterial community, and gas flux measurements to quantify CH4 emissions, we looked for differences between classically defined CH4 sinks (meadow soils) and CH4 sources (paddy fields). Analysis of the total bacterial community revealed that the family Fimbriimonadaceae, which belongs to the phylum Armatimonadetes, was significantly higher in paddy field soils driving the difference between paddy and meadow soils. Whereas, we found that the methylotrophic families Methyloligellaceae and Methylomirabilaceae were also present in higher relative abundance in the paddy field. Despite these major differences, CH4 fluxes were highly variable between the two sites with no significant differences observed. Furthermore, we found the Methylomonaceae family to be more abundant at the center of a neighboring paddy field compared to the edge of the paddy field from the current study, hinting at methanotrophic variation based on location. Taking these results into account, we propose a conceptual model to explain possible scenarios that may result in paddy and meadow fields not exhibiting classical source/sink properties. These findings call for caution when including paddy and meadow areas separately into global CH4 flux calculations, and urge further research to discern drivers of CH4 cycling under a range of environmental conditions rather than relying on assumptions.

Introduction

The Introduction traces the history of modern scholarship on Hobbes’s understanding of rhetoric and its relationship to the development and articulation of his philosophy, arguing that this has been misconstrued. The received view that Hobbes began as a Ciceronian humanist who rejected an early confidence in the value of rhetoric on turning to science around 1640, only to re-embrace it as a necessary part of civil philosophy in Leviathan is called into question by scrutiny of some of the key passages commonly adduced in its support. Hobbes’s critique of that humanist mantra, the association of ratio and oratio (an association unstable even in its classical source) represents not a narrow attack on oratory, but a broad concern about the character of human language. Second, Hobbes’s apparent insistence, at the close of Leviathan, on the need for reason to be backed by eloquence involves a misreading of that much cited passage.

Experimenting with a new tragic model: Elechi Amadi’s Isiburu

Aristotle’s Poetics has remained one of the most resourceful reference materials to literary critics and theorists over the centuries from classical antiquity to contemporary times. However, in spite of its lofty status and acclaim the classical source material has also faced serious criticisms especially concerning certain unrealistic and vague postulations made in it about tragedy. The most challenged postulations are those relating to the status of the tragic hero, his flaw, the emotions of pity and fear, and catharsis. Some of these “problematic” areas constitute the crux of Elechi Amadi’s concern in “Gods and Tragic Heroes,” a polemical essay on which this study hinges. Re-examining some existing conversations on the subject and Amadi’s charges against Aristotle, the essay affirms that tragedy is a flexible literary form and that Amadi, amidst his evaluation of Aristotle’s enduring aesthetics, proposes a novel model in which hamartia and the emotional impacts of the hero’s fall on the audience are a function of an overarching supernatural activity in the tragic plot. Consequently, the essay appraises Isiburu as Amadi’s practical example of the proposed model.