992 resultados para LEE-YANG THEOREM


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Despite the fact that the integral form of the equations of classical electrodynamics is well known, the same is not true for non-Abelian gauge theories. The aim of the present paper is threefold. First, we present the integral form of the classical Yang-Mills equations in the presence of sources and then use it to solve the long-standing problem of constructing conserved charges, for any field configuration, which are invariant under general gauge transformations and not only under transformations that go to a constant at spatial infinity. The construction is based on concepts in loop spaces and on a generalization of the non-Abelian Stokes theorem for two-form connections. The third goal of the paper is to present the integral form of the self-dual Yang-Mills equations and calculate the conserved charges associated with them. The charges are explicitly evaluated for the cases of monopoles, dyons, instantons and merons, and we show that in many cases those charges must be quantized. Our results are important in the understanding of global properties of non-Abelian gauge theories.

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This paper examines consumers self-referencing as a mechanism for explaining ethnicity effects in advertising. Data was collected from a 2 (model ethnicity: Asian, white) x 2 (product stereotypicality: stereotypical, non-stereotypical) experiment. Measured independent variables included participant ethnicity and self-referencing. Results shows that (1) Asian exhibit greater self-referencing of Asian models than whites do; (2) self-referencing mediates ethnicity effects on attitude ( ie, attitude towards the model, attitude toward the add, brand attitude, and purchase intentions); (3) high self-referencing Asian have more favourable attitude towards the add and purchase intentions than low self referencing Asians; and (4) Asian models advertising atypical products generate more self-referencing and more favourable attitudes toward the model, A, and purchase intentions for both Asians and whites.

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There are various principles for layout design such as balance, rhythm, unity and harmony, but each principle has often been introduced as a separate concept rather than within an integrated and systematic structure, so that designers and design students have to keep practices for the acquisition of skills. The paper seeks to develop a conceptual framework for a systematic mapping of layout design principles by using Yin and Yang and the Five Elements. Yin and Yang theory explains all natural phenomena with its own conceptual model and facilitates finding harmony and balance between the visual elements in terms of systematic and organic relations. Most common and well-known layout design principles are defined with 10 different resources such as design books and articles, and have been remapped following with the structure of Yin and Yang and the Five Elements. A systematic framework explaining the relationships of design principles was created and 32 design students participated in its efficiency test. The outcome suggests there is a high possibility that the framework can be used in professional fields and design education.

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The population Monte Carlo algorithm is an iterative importance sampling scheme for solving static problems. We examine the population Monte Carlo algorithm in a simplified setting, a single step of the general algorithm, and study a fundamental problem that occurs in applying importance sampling to high-dimensional problem. The precision of the computed estimate from the simplified setting is measured by the asymptotic variance of estimate under conditions on the importance function. We demonstrate the exponential growth of the asymptotic variance with the dimension and show that the optimal covariance matrix for the importance function can be estimated in special cases.

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There is a growing body of work that responds to the impact of the rapid uptake of information and communication technology (ICT) on education (Buckingham, 2003; Cheung, 2003; Cuban, 2003; Leung, 2003; Prensky, 2005; Green & Hannon, 2007; Brooks-Gunn & Donahue, 2008; Lyman et al, 2008). Mostly, this work has been positioned in the context of upper-primary or secondary classrooms. More recently, there has been a growing call for research about the impact of ICT on the early years or in early childhood contexts. This text initiates a response to that call. The authors concur that today’s children are a generation who create, learn, work, play and communicate very differently from their parents and teachers (Buckingham, 2003), and that classroom activity needs to reflect this difference.

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Volume measurements are useful in many branches of science and medicine. They are usually accomplished by acquiring a sequence of cross sectional images through the object using an appropriate scanning modality, for example x-ray computed tomography (CT), magnetic resonance (MR) or ultrasound (US). In the cases of CT and MR, a dividing cubes algorithm can be used to describe the surface as a triangle mesh. However, such algorithms are not suitable for US data, especially when the image sequence is multiplanar (as it usually is). This problem may be overcome by manually tracing regions of interest (ROIs) on the registered multiplanar images and connecting the points into a triangular mesh. In this paper we describe and evaluate a new discreet form of Gauss’ theorem which enables the calculation of the volume of any enclosed surface described by a triangular mesh. The volume is calculated by summing the vector product of the centroid, area and normal of each surface triangle. The algorithm was tested on computer-generated objects, US-scanned balloons, livers and kidneys and CT-scanned clay rocks. The results, expressed as the mean percentage difference ± one standard deviation were 1.2 ± 2.3, 5.5 ± 4.7, 3.0 ± 3.2 and −1.2 ± 3.2% for balloons, livers, kidneys and rocks respectively. The results compare favourably with other volume estimation methods such as planimetry and tetrahedral decomposition.

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We performed an integrated genomic, transcriptomic and proteomic characterization of 373 endometrial carcinomas using array- and sequencing-based technologies. Uterine serous tumours and ∼25% of high-grade endometrioid tumours had extensive copy number alterations, few DNA methylation changes, low oestrogen receptor/progesterone receptor levels, and frequent TP53 mutations. Most endometrioid tumours had few copy number alterations or TP53 mutations, but frequent mutations in PTEN, CTNNB1, PIK3CA, ARID1A and KRAS and novel mutations in the SWI/SNF chromatin remodelling complex gene ARID5B. A subset of endometrioid tumours that we identified had a markedly increased transversion mutation frequency and newly identified hotspot mutations in POLE. Our results classified endometrial cancers into four categories: POLE ultramutated, microsatellite instability hypermutated, copy-number low, and copy-number high. Uterine serous carcinomas share genomic features with ovarian serous and basal-like breast carcinomas. We demonstrated that the genomic features of endometrial carcinomas permit a reclassification that may affect post-surgical adjuvant treatment for women with aggressive tumours.

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This paper is the edited transcript of a conversation between Susan Carson and Donna Lee Brien about an administrator’s perspective of the process of examining doctoral theses in the creative industries. Susan was central to the process in the Faculty of Creative Industries from 2008 to 2012, and has overseen the carriage of examination for creative arts theses in the creative industries disciplines of creative writing, performance studies, media and communication, journalism, film and television, visual arts, and interaction and visual design.