Augmented Superfield Approach To Unique Nilpotent Symmetries For Complex Scalar Fields In QED

The derivation of the exact and unique nilpotent Becchi-Rouet-Stora-Tyutin (BRST)- and anti-BRST symmetries for the matter fields, present in any arbitrary interacting gauge theory, has been a long-standing problem in the framework of superfield approach to BRST formalism. These nilpotent symmetry transformations are deduced for the four (3 + 1)-dimensional (4D) complex scalar fields, coupled to the U(1) gauge field, in the framework of augmented superfield formalism. This interacting gauge theory (i.e. QED) is considered on a six (4, 2)-dimensional supermanifold parametrized by four even spacetime coordinates and a couple of odd elements of the Grassmann algebra. In addition to the horizontality condition (that is responsible for the derivation of the exact nilpotent symmetries for the gauge field and the (anti-)ghost fields), a new restriction on the supermanifold, owing its origin to the (super) covariant derivatives, has been invoked for the derivation of the exact nilpotent symmetry transformations for the matter fields. The geometrical interpretations for all the above nilpotent symmetries are discussed, too.Comment: LaTeX file, 17 pages, journal versio

Visual Rhetoric in Outdoor Advertising

The paper presents a research, the aim of which is to find out how graphic expressions and visual language can be used for persuasion. The research material consists of outdoor advertisements photographed in their actual exhibition places in a city environment. Outdoor advertising media, which are used to communicate visual messages from a sender to several addressees, participate in building the visual city culture and open manifold solutions in design. The visual language used in the research material is analyzed in order to find out how advertising messages, their denotations and connotations, are constructed and how arguments used for persuasion are visualized. The first analysis is based on the knowledge and methods used in graphic design practice, which has been defined to be the process of making, choosing and arranging marks in order to convey a message. The analysis shows that different modes, techniques and visual elements are applied to attract the attention of spectators and arouse interest towards the message of an artefact. The second analysis is based on communication studies and semiotics, especially on Roman Jakobson’s theory about the functions of communication. The method of combining two analyses reveals different ways of using visual language and syntaxes to announce the excellence of an advertised product, service or subject. It also shows various types of visual arguments used in advertisements. Three types of visual rhetoric emerge from the research material. They are called brand rhetoric, personalized rhetoric and poetic rhetoric. The taxonomy of visual rhetoric exemplifies how visual language can be constructed and used for persuasion. It shows that the decisions in design influence the messages and meanings created. The research calls for further studies as regards the reception of visual rhetoric and suggests that the taxonomy of visual rhetoric could be applied in visual communication design and in the analysis of advertising messages. Keywords: Outdoor Advertisement/Advertising; Visual Rhetoric; Visual Language; Graphic Design; Visual Communication Design; Advertising Message</p

Distinct expressions of the BSR using various frequencies offshore Uruguay and its correspondence with the gas hydrate stability zone

At the Uruguayan continental margin, seismic evidence for the occurrence of gas hydrate has been identified based on the presence of BSRs in densely spaced 2D reflection seismic sections from different surveys. Mapping of BSRs based on 2D seismic data acquired in 2007 and 2008 suggested the presence of gas hydrates in areas that were not previously identified; hence hydrate occurrence offshore Uruguay is more widespread than previously thought. Recently ANCAP has digitized offshore seismic data acquired between 1970 and 1982. Being able to work on this data using interpretation software, and integrating results with the latest interpretations performed on the seismic collected in 2007 and 2008, the BSR extends over an area of approximately 25.000 km2. It is present in water depths greater than 500 m and has high continuity in Pelotas Basin but is more discontinuous at Punta del Este Basin and southern part of Oriental del Plata Basin. In offshore basins around the world the base of GHSZ can have different seismic expressions such as continuous, segmented, and high-relief BSRs depending on the stratigraphic, fluid and geothermal setting. Here, we present examples of the influence of the acquisition parameters on the acoustic expression of the BSR, comparing commercial seismic sections acquired for hydrocarbon exploration and high resolution seismic sections acquired during the R/V Meteor Cruise M49/2 in 2001 and R/V Meteor Cruise M78/3a (May - June 2009) using different sources and streamer system. For the different data sets the BSR presents differences regarding its continuity and amplitude strength. In high resolution seismic, enhanced amplitudes and phase reversals are observed for several reflectors while deep penetration seismic shows only one single continuous reflector. This comparison may help to visualize the complexity of the free gas, gas hydrate and stratigraphic system behind the BSR, which is usually masked on low-frequency deep penetration seismic data

Crossing Disciplinary Borders: Latino/a Studies and Latin American Studies in the 1990s

Over the 30 years of their existence, studies of Latinos/as in the U.S. and the field of Latin American Studies have emerged largely as divided disciplines. That is, despite what would appear to be similar sensibilities including comparable criticisms of Western hegemony and the neocolonial practices of the U.S., as well as the political, economic, and cultural displacement of similar populations, the two areas of study have more often regarded each other as competitive colleagues rather than complimentary practices. In the following study, I examine the nature of the two disciplines paying particular attention to the political context surrounding their formations and the foundations of their discursive frameworks. I examine changes to these disciplines in the methodological and ideological shifts surrounding the emergence of empirical and postmodern studies, and the relationship between these theoretical shifts and the expansion of globalization. Finally, I conclude with a discussion of the emerging field of transnational and bi-national studies and the opportunities for crossing the disciplinary borders between Latino/as studies in the U.S. and Latin American Studies presented in this literature