Using small-angle X-ray scattering to investigate the compaction behaviour of a granulated clay

The compaction behaviour of a commercial granulated clay (magnesium aluminium smectite, gMgSm) was investigated using macroscopic pressure-density measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray microtomography (XμT) and small-angle X-ray scattering (SAXS). This material was studied as a potential compaction excipient for pharmaceutical tabletting, but also as a model system demonstrating the capabilities of SAXS for investigating compaction in other situations. Bulk compaction measurements showed that the gMgSm was more difficult to compact than polymeric pharmaceutical excipients such as spheronised microcrystalline cellulose (sMCC), corresponding to harder granules. Moreover, in spite of using lubrication (magnesium stearate) on the tooling surfaces, rather high ejection forces were observed, which may cause problems during commercial tabletting, requiring further amelioration. Although the compacted gMgSm specimens were more porous, however, they still exhibited acceptable cohesive strengths, comparable to sMCC. Hence, there may be scope for using granular clay as one component of a tabletting formulation. Following principles established in previous work, SAXS revealed information concerning the intragranular structure of the gMgSm and its response to compaction. The results showed that little compression of the intragranular morphology occurred below a relative density of 0 · 6, suggesting that granule rearrangements or fragmentation were the dominant mechanisms during this stage. By contrast, granule deformation became considerably more important at higher relative density, which also coincided with a significant increase in the cohesive strength of compacted specimens. Spatially-resolved SAXS data was also used to investigate local variations in compaction behaviour within specimens of different shape. The results revealed the expected patterns of density variations within flat-faced cylindrical specimens. Significant variations in density, the magnitude of compressive strain and principal strain direction were also revealed in the vicinity of a debossed feature (a diametral notch) and within bi-convex specimens. The variations in compaction around the debossed notch, with a small region of high density below and low density along the flanks, appeared to be responsible for extensive cracking, which could also cause problems in commercial tabletting

Finding Significant Fourier Coefficients: Clarifications, Simplifications, Applications and Limitations

Ideas from Fourier analysis have been used in cryptography for the last three decades. Akavia, Goldwasser and Safra unified some of these ideas to give a complete algorithm that finds significant Fourier coefficients of functions on any finite abelian group. Their algorithm stimulated a lot of interest in the cryptography community, especially in the context of `bit security'. This manuscript attempts to be a friendly and comprehensive guide to the tools and results in this field. The intended readership is cryptographers who have heard about these tools and seek an understanding of their mechanics and their usefulness and limitations. A compact overview of the algorithm is presented with emphasis on the ideas behind it. We show how these ideas can be extended to a `modulus-switching' variant of the algorithm. We survey some applications of this algorithm, and explain that several results should be taken in the right context. In particular, we point out that some of the most important bit security problems are still open. Our original contributions include: a discussion of the limitations on the usefulness of these tools; an answer to an open question about the modular inversion hidden number problem

Eco-Geologies of Queer Desire: Elizabeth Bishop’s Love Poetry and Charles Darwin’s Beagle Geology Travel Narratives

This essay explores the impact of Charles Darwin’s often poetic, largely geological travel narratives – the Diary and Voyage of the Beagle – on Elizabeth Bishop’s queered travel poems “Crusoe in England”(1976) and “Vague Poem”(circa 1973), in the context of recent feminist theory’s materialist ecological “turn.” I survey Bishop’s shift from her early Freudian, “primordial” rocky landscapes, projecting submerged desires for a seductive mother figure, to her later deliberate materializations of these psychosexual realms in “the real” of geology’s unfolding forces and flows. Adapting Darwin’s similarly haunted, dark, Romantic accounts of his voyaging into crustal earth, Bishop’s “Crusoe” and “Vague Poem” variously enact an immersion in earth’s unfolding volcanic or crystalline ancestral past, which successively opens out “eco-geologically” to enmesh queer human intimacy/the body. Theoretically, Bishop’s Darwinian love poems richly materialize the queer body while redefining our enmeshment in nature as the wellspring of achieved being, intimacy, and desire. Further, Bishop’s poems offer a newly relevant feminist ecology within our so-called Anthropocene era of humanly caused, unnaturally accelerated geology. Bishop effectively inserts a “differently” sexed/gendered relation to geologic forces and materialities, thereby countering the neglectful patriarchal anthropos currently scarring our planet

A Foundation for International Taxation: The Institutional Competence of Nations

This Article proposes a conceptual foundation for the field of international tax law. The Article refers to this foundation as the institutional competence of nations in global economic development. A nation’s institutional competence is its discretion to make decisions in pursuit of our collective goal of global economic development, discretion that is subject to a number of standards and limitations. The Article constructs the institutional competence of nations in global economic development from institutional economics, simple game theory, and the literature on social norms. The Article expresses the institutional competence of nations through standards and limitations that reduce the abuse of sovereign discretion and address international collective action problems in the pursuit of global economic development. These standards and limitations allocate prescriptive jurisdiction among nations over the global income tax base. The foundation proposed by the Article would coordinate international taxation with the international regulation of trade. The Article also addresses the proper place of capital export neutrality in the hierarchy of values for economic development, the choice between territorial and worldwide tax systems, the evaluation of tax havens and appropriate responses, the use of anti-deferral regimes, and the possible need for a multilateral tax treaty. On this institutional foundation, the role of the state is both essential and subordinate: sovereignty becomes an instrumental value and national law-making is seen in terms of a conceptual subsidiarity, to use the European term, or a consequentialist federalism in the realm of global economic development. Moreover, non-state actors facilitate sovereign competition and the benefits that such a constraint on the abuse of sovereign discretion brings to the world’s people

The United States\u27 Response to Tax Havens: The Foreign Base Company Services Income of Controlled Foreign Corporations

This article is a detailed study of the taxation by the United States of foreign base company services income. Foreign base company services in- come is defined generally as the income derived by a controlled foreign corporation from the performance of services for a related person.2 Con- trolled foreign corporations, in turn, generally are the foreign subsidiaries of U.S. parent corporations.3 A controlled foreign corporation\u27s foreign base company services income is taxed to its U.S. parent corporation, subject to various exclusions and qualifications. This article defines the class of sus- pect relationships between the controlled foreign corporation and its related persons and delineates the category of relevant services. The article\u27s con- tributions to the literature on controlled foreign corporations include: the proper coordination of the guaranty-plus rule with the substantial assistance rule;4 a critique of the avoidance of tax through the use of branches and, more generally, of the requirement that a related person figure in a tax ha- ven arrangement before the United States imposes tax;5 a clear analysis of the complex relationship among related-person factoring, foreign personal holding company income, and foreign base company services income;6 and \u27 Subpart F in the parlance of international tax lawyers comprises sections 951-964 of the Internal Revenue Code. Section 954(e) defines foreign base company services income, the subject matter of this article. There is very little legislative history for section 954(e). The provision originated in the Senate as an amendment to what was to become the Revenue Act of 1962, Pub. L. No. 87-834, § 12, 76 Stat. 960, 1006 (1962). S. REP. No. 1881, 87th Cong., 2d Sess. (1962), reprinted in 1962-3 C.B. 703, 785. The Senate Report states only that the purpose of the provision is to deny tax deferral where a service subsidiary is separated from manufacturing or similar activities of a related corporation and organized in another country primarily to obtain a lower rate of tax for the service income. Id. at 790. Code section 954(e) is broader in scope, of course, and reaches a service subsidiary that is separated from a U.S. parent corporation that engages only in services. Examples include corporations en- gaged in engineering, construction, or oil field services

The Unlikely Milliner & The Magician of Threadneedle-Street [Article]

Susanna Clarke uses the tarot in her novel Jonathan Strange & Mr Norrell much as she uses history: twisting it to open up spaces for magic and playfulness. She offers modifications on the traditional Tarot de Marseille that accurately predict the narrative events, yet deftly obscures the outcomes by leading the readers (and the characters) to jump to the wrong conclusions. Laity’s analysis of the Tarot readings performed by Childermas and Vinculus shows that Strange and Norrell enjoy mastery in magic, only to find that that mastery brings great suffering to others and also isolates them from the world as they once knew it