925 resultados para photocopied journal articles and book chapters


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The particle sizes, morphologies, and structures are presented for succinic acid particles formed from the evaporation of uniform droplets created with a vibrating orifice aerosol generator. Particle sizes are monodisperse, and solvent choice is found to be the dominant factor in determining the final morphology and structure. The external particle morphologies range from round to cap shaped, while the surface roughness ranges from fairly smooth to extremely rough and pitted. Internally, the particles have significant void space and noticeable crystals. X-ray diffraction confirms that the particles are crystalline. Thus, the morphologies of the particles take on a crystal filled structure that is unique in comparison to previous particles formed through droplet evaporation. The structure of the particles contains β succinic acid; however, the particles formed from water also contain α succinic acid. α Succinic acid has not previously been able to be formed from solution at near atmospheric conditions. The unique morphologies and ability to identify unexpected polymorphs provide for a potential tool to not only enhance particle engineering but also to identify metastable polymorphs.

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We introduce a class of distance-dependent interactions in an accelerated exclusion process inspired by the observation of transcribing RNA polymerase speeding up when “pushed” by a trailing one. On a ring, the accelerated exclusion process steady state displays a discontinuous transition, from being homogeneous (with augmented currents) to phase segregated. In the latter state, the holes appear loosely bound and move together, much like a train. Surprisingly, the current-density relation is simply J=1-ρ, signifying that the “hole train” travels with unit velocity.

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Different codons encoding the same amino acid are not used equally in protein-coding sequences. In bacteria, there is a bias towards codons with high translation rates. This bias is most pronounced in highly expressed proteins, but a recent study of synthetic GFP-coding sequences did not find a correlation between codon usage and GFP expression, suggesting that such correlation in natural sequences is not a simple property of translational mechanisms. Here, we investigate the effect of evolutionary forces on codon usage. The relation between codon bias and protein abundance is quantitatively analyzed based on the hypothesis that codon bias evolved to ensure the efficient usage of ribosomes, a precious commodity for fast growing cells. An explicit fitness landscape is formulated based on bacterial growth laws to relate protein abundance and ribosomal load. The model leads to a quantitative relation between codon bias and protein abundance, which accounts for a substantial part of the observed bias for E. coli. Moreover, by providing an evolutionary link, the ribosome load model resolves the apparent conflict between the observed relation of protein abundance and codon bias in natural sequences and the lack of such dependence in a synthetic gfp library. Finally, we show that the relation between codon usage and protein abundance can be used to predict protein abundance from genomic sequence data alone without adjustable parameters.

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Calcineurin-inhibitor refractory bronchiolitis obliterans (BO) represents the leading cause of late graft failure after lung transplantation. T helper (Th)2 and Th17 lymphocytes have been associated with BO development. Taking advantage of a fully allogeneic trachea transplantation model in mice, we addressed the pathogenicity of Th cells in obliterative airway disease (OAD) occurring in cyclosporine A (CsA)-treated recipients. We found that CsA prevented CD8+ T cell infiltration into the graft and downregulated the Th1 response but affected neither Th2 nor Th17 responses in vivo. In secondary mixed lymphocyte cultures, CsA dramatically decreased donor-specific IFN-γ production, enhanced IL-17 production and did not affect IL-13. As CD4+ depletion efficiently prevented OAD in CsA-treated recipients, we further explored the role of Th2 and Th17 immunity in vivo. Although IL-4 and IL-17 deficient untreated mice developed an OAD comparable to wild-type recipients, a single cytokine deficiency afforded significant protection in CsA-treated recipients. In conclusion, CsA treatment unbalances T helper alloreactivity and favors Th2 and Th17 as coexisting pathways mediating chronic rejection of heterotopic tracheal allografts.

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A uniform algebra A on its Shilov boundary X is maximal if A is not C(X) and no uniform algebra is strictly contained between A and C(X) . It is essentially pervasive if A is dense in C(F) whenever F is a proper closed subset of the essential set of A. If A is maximal, then it is essentially pervasive and proper. We explore the gap between these two concepts. We show: (1) If A is pervasive and proper, and has a nonconstant unimodular element, then A contains an infinite descending chain of pervasive subalgebras on X . (2) It is possible to find a compact Hausdorff space X such that there is an isomorphic copy of the lattice of all subsets of N in the family of pervasive subalgebras of C(X). (3) In the other direction, if A is strongly logmodular, proper and pervasive, then it is maximal. (4) This fails if the word “strongly” is removed. We discuss examples involving Dirichlet algebras, A(U) algebras, Douglas algebras, and subalgebras of H∞(D), and develop new results that relate pervasiveness, maximality, and relative maximality to support sets of representing measures.

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We show that to each inner function, there corresponds at least one interpolating Blaschke product whose angular derivatives have precisely the same behavior as the given inner function. We characterize the Blaschke products invertible in the closed algebra generated by the algebra of bounded analytic functions and the conjugates of Blaschke products with angular derivative finite everywhere. We study the most well-known example of a Blaschke product with infinite angular derivative everywhere and show that it is an interpolating Blaschke product. We conclude the paper with a method for constructing thin Blaschke products with infinite angular derivative everywhere.

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Nettie Honeyball and Florence Dixie founded the British Ladies Football Club (BLFC) in 1894 with the aim to provide football-playing opportunities for girls and young women, but also as a means of making money. Theirs, in effect, was an attempt to create a professional football league for women. Public interest in 'the lady footballers' was enormous, at least in its early stages, and generated considerable attention from the press. Overall, press coverage of the BLFC was negative (football is a man's sport; football is a working-class sport; women are physically incapable of playing the game; women shouldn't appear publicly in bifurcated garments, etc.), with only a few notable exceptions. Did the stance adopted depend on the political leaning of the newspaper? Or were the reporters simply reflecting the social and economic realities of their time, struggling to 'explain' a marginal group - women athletes, or more specifically, middle-class women football players - engaging in a working-class male game? This article examines the press coverage of the BLFC. The double standard evident in the newspaper coverage was, on the surface, as one might expect: if a woman played well, she was a freak, possibly a man in disguise; if she didn't play well, it proved that women shouldn't play football. But on closer examination, the double standard was actually rather nuanced: if she played well and looked the part of a woman, she could be subject to praise; yet if she played well and didn't conform to the standard of feminine beauty, she faced ridicule, and her gender called into question.

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An introductory course in probability and statistics for third-year and fourth-year electrical engineering students is described. The course is centered around several computer-based projects that are designed to achieve two objectives. First, the projects illustrate the course topics and provide hands-on experience for the students. The second and equally important objective of the projects is to convey the relevance and usefulness of probability and statistics to practical problems that undergraduate students can appreciate. The benefit of this course as to motivate electrical engineering students to excel in the study of probability concepts, instead of viewing the subject as one more course requirement toward graduation. The authors co-teach the course, and MATLAB is used for mast of the computer-based projects

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A new idea for waveform coding using vector quantisation (VQ) is introduced. This idea makes it possible to deal with codevectors much larger than before for a fixed bit per sample rate. Also a solution to the matching problem (inherent in the present context) in the &-norm describing a measure of neamess is presented. The overall computational complexity of this solution is O(n3 log, n). Sample results are presented to demonstrate the advantage of using this technique in the context of coding of speech waveforms.

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The discrete cosine transform (DCT) is an important functional block for image processing applications. The implementation of a DCT has been viewed as a specialized research task. We apply a micro-architecture based methodology to the hardware implementation of an efficient DCT algorithm in a digital design course. Several circuit optimization and design space exploration techniques at the register-transfer and logic levels are introduced in class for generating the final design. The students not only learn how the algorithm can be implemented, but also receive insights about how other signal processing algorithms can be translated into a hardware implementation. Since signal processing has very broad applications, the study and implementation of an extensively used signal processing algorithm in a digital design course significantly enhances the learning experience in both digital signal processing and digital design areas for the students.

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This article offers an analysis of a struggle for control of a women’s development project in Nepal. The story of this struggle is worth telling, for it is rife with the gender politics and neo-colonial context that underscore much of what goes on in contemporary Nepal. In particular, my analysis helps to unravel some of the powerful discourses, threads of interest, and yet unintended effects inevitable under a regime of development aid. The analysis demonstrates that the employment of already available discursive figures of the imperialist feminist and the patriarchal third world man are central to the rhetorical strategies taken in the conflict. I argue that the trans-discursive or “borderland” nature of development in general and women’s development in particular result in different constructions of “development” goals, means and actors based not only on divergent cultural categories but on historically specific cultural politics. I argue further that the apolitical discourse of development serves to cloak its inherently political project of social and economic transformation, making conflicts such as the one that occurred in this case not only likely to occur but also likely to be misunderstood.

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In this article, I examine the values and meanings that adhere to objects made by Maithil women at a development project in Janakpur, Nepal – objects collectors have called ‘Janakpur Art’. I seek to explain how and why changes in pictorial content in Janakpur Art – shifts that took place over a period of five or six years in the 1990s – occurred, and what such a change might indicate about the link between Maithil women’s lives, development, and tourism. As I will demonstrate, part of the appeal for consumers of Janakpur Art has been that it is produced at a ‘women’s development project’ seeking to empower its participants. And yet, the project’s very successes threaten to displace the producers (and what they produce) from their perceived qualities/identities as ‘traditional’ and ‘primitive,’ thereby bringing into question the authenticity of the ‘art’ they produce. The conundrum begs this question: can developing women produce primitive art?

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Drawing on ethnographic research and employing a micro-historical approach that recognizes not only the transnational but also the culturally specific manifestations of modernity, this article centers on the efforts of a young woman to negotiate shifting and conflicting discourses about what a good life might consist of for a highly educated and high caste Hindu woman living at the margins of a nonetheless globalized world. Newly imaginable worlds in contemporary Mithila,South Asia, structure feeling and action in particularly gendered and classed ways, even as the capacity of individuals to actualize those worlds and the “modern” selves envisioned within them are constrained by both overt and subtle means. In the context of shifting cultural anchors, new practices of silence, literacy, and even behaviors interpreted as “mental illness” may become tactics in an individual’s negotiation of conflicting self-representations. The confluence of forces at play in contemporary Mithila, moreover, is creating new structures of feeling that may begin to reverse long-standing locally held assumptions about strong solidarities between natal families and daughters, on the one hand, and weak solidarities between affinal families and new daughters-in-law, on the other.