Os objetivos deste trabalho são: i) Fixado um inteiro positivo n, estudar dois métodos "construtivos" para aproximar-se uma função real contínua definida na esfera unitária S ^{r-1} de R^r, por polinômios esféricos de grau <=n; ii) Obter estimativas para as normas dos operadores de interpolação e hiperinterpolação, comparando-as com a norma da projeção ortogonal de C(S^{r-1}) sobre o espaço de polinômios onde as aproximações residem. / This work addresses two issues: i) To study two constructive methods to approximate a real continuous function on the unit sphere S^{r-1} of R^r by spherical polynomials of degree <=n (n fixed); ii) To estimate the norms of the interpolation and hyperinterpolation operators, comparing them with the norm of the orthogonal projection of C(S^{r-1}) over the polynomial space where the approximations live.

Many scholars suggest that credit networks were fundamental to the operation of early modern towns. Unfortunately, the majority of this scholarship ignores the role of women in the debt and credit system. The legal position of early modern women and the nature of the available sources mean that womens experiences are generally not documented in any significant numbers. Historians are therefore forced to speculate on how women might have been involved in borrowing and lending and often end up writing as though the female experience of credit was identical to mens experience of the system. The records of the Baillie Court of Aberdeen, Scotland offer a glimpse at women engaging in debt and credit transactions in large numbers and pursuing transactions that went awry. This study looks at 671 debt cases brought before Aberdeens court system in two years in the late seventeenth-century and reveals that women participated in 46% of these cases. Similar studies, focusing mainly on England, have found female participation in debt and credit to hover closer to the 15% range. While there are some unique characteristics that might explain how Aberdeen would see more women becoming involved in the court system, there is little evidence that Aberdonian women were unusually active in the debt and credit system as a whole, in comparison to the rest of early modern Europe. Instead, Aberdeens court records reveal what was likely a very common, but undocumented, experience in the rest of the pre-industrial world. As a result of this unprecedented level of documentation, we see women involved who would otherwise be invisible to us. The Baillie Court shows married women involved in far greater numbers than either single women or widows, a fact which goes against the traditional image of single and widowed women as the only ones involved in the credit system through their roles as moneylenders. Instead, we find another level of women using debt and credit to secure goods for their households and participating in the economy of the town. We find that, although women were heavily involved in borrowing and lending, their experience of that system was significantly different than that of early modern men. The causes of debt and the amounts for which people would both sue and be sued were substantially different depending on ones gender and marital status. While the statistics that come out of this study are impressive, the human stories are even more enlightening. By examining individual cases, we can see how women negotiated the debt and credit and how they shaped that system to their own needs.

Many scholars suggest that credit networks were fundamental to the operation of early modern towns. Unfortunately, the majority of this scholarship ignores the role of women in the debt and credit system. The legal position of early modern women and the nature of the available sources mean that womens experiences are generally not documented in any significant numbers. Historians are therefore forced to speculate on how women might have been involved in borrowing and lending and often end up writing as though the female experience of credit was identical to mens experience of the system. The records of the Baillie Court of Aberdeen, Scotland offer a glimpse at women engaging in debt and credit transactions in large numbers and pursuing transactions that went awry. This study looks at 671 debt cases brought before Aberdeens court system in two years in the late seventeenth-century and reveals that women participated in 46% of these cases. Similar studies, focusing mainly on England, have found female participation in debt and credit to hover closer to the 15% range. While there are some unique characteristics that might explain how Aberdeen would see more women becoming involved in the court system, there is little evidence that Aberdonian women were unusually active in the debt and credit system as a whole, in comparison to the rest of early modern Europe. Instead, Aberdeens court records reveal what was likely a very common, but undocumented, experience in the rest of the pre-industrial world. As a result of this unprecedented level of documentation, we see women involved who would otherwise be invisible to us. The Baillie Court shows married women involved in far greater numbers than either single women or widows, a fact which goes against the traditional image of single and widowed women as the only ones involved in the credit system through their roles as moneylenders. Instead, we find another level of women using debt and credit to secure goods for their households and participating in the economy of the town. We find that, although women were heavily involved in borrowing and lending, their experience of that system was significantly different than that of early modern men. The causes of debt and the amounts for which people would both sue and be sued were substantially different depending on ones gender and marital status. While the statistics that come out of this study are impressive, the human stories are even more enlightening. By examining individual cases, we can see how women negotiated the debt and credit and how they shaped that system to their own needs.

Agricultural journalism and agricultural communication have been researched in depth, identifying job skills, job satisfaction, educational backgrounds, and curriculum issues. However, a study examining the spheres (subjective, institutional, contextual, and societal) that influence how agricultural journalists and communicators do their jobs—as indicated by Esser’s (as cited in Frölich & Holtz–Bacha, 2003) model of spheres of influence on journalists—could not be found. This study utilized Esser’s model to identify those factors and determine whether their influences differ demographically. A total of 256 members of the International Federation of Agricultural Journalists, American Agricultural Editors’ Association, North American Agricultural Journalists, and Association for Communication Excellence in Agriculture, Natural Resources, and Life and Human Sciences responded to a researcher-designed instrument and a thirdparty Web-based survey tool. The respondents demographically resembled populations in similar studies. Data were analyzed using statistical tools and quantitative content analysis. This study found a relationship between the jobs that agricultural journalists and communicators do and the societal sphere (p=.04), which includes personal values, desire for self-realization, professional values, and conception of a journalist’s role. The spheres of influence of international organization (IFAJ, AAEA, and NAAJ) members and domestic organization (ACE) members were compared. The difference in the societal sphere was of medium effect size (d = .39), indicating that organizational membership influences members’ perceptions about themselves and their roles. Respondents indicated the most important skills for new agricultural journalists were personal attributes and skills, such as curiosity and adaptability; writing; and communication. The most important skills for new agricultural communicators were communication, personal attributes and skills, and journalistic skills. The most important future issue for agricultural journalists and communicators was agricultural technology and development. The findings indicate that agricultural journalists and communicators are influenced by their personal and professional values, perception of their professional roles, and desire for self-realization. Future agricultural journalists and communicators should seek training in personal attributes and skills, writing, communication, and journalistic skills. This study contributes to research in agricultural journalism and communication because it encompasses a global perspective by including respondents outside North America.

From its distinction during the 1920s as the hub of black culture and commerce in America to its later reputation as the unmitigated manifestation of inner city decay, Harlem evokes an urban palimpsest, a lived geographic space onto which collective desires and fears are written and overwritten. Because of the symbolic place Harlem occupies in the national imaginary, my dissertation focuses on this central public site. Jay-Walking in the City: Violence Against Women, Urban Space, and Pedestrian Acts of Resistance advocates an investigation of textual histories of abusive domestic experiences in this neighborhood in order to underline the importance of public spheres in redressing trauma. As part of the larger archive of Harlem literature, the novels I investigate in this dissertation offer counter-narratives to those circulating in post-war America concerning the safety of this neighborhood’s streets and the character of its residents. Ann Petry’s The Street (1946), Gloria Naylor’s The Women of Brewster Place (1980), Audre Lorde’s Zami: A New Spelling of My Name (1982), and Sapphire’s Push (1996) all contain episodes of domestic or sexual violence against women perpetrated in the Harlem households where the protagonists of these novels live. This dissertation focuses on the moments when Harlemites whom these women encounter in the public sphere intervene in the violent conditions of these primary characters’ lives. These interposal episodes within each novel challenge the pervasive cultural dichotomy that extols the American home as a stronghold of social and national security and lambastes the inner city as a volatile space of danger and fear. / text

Circles, parabolas, ellipses and hyperbolas are conic sections and have many unique properties. The properties of the tangents to conic sections prove quite interesting. Dandelin spheres are tangent to ellipses inside a cone and support the geometric definition of an ellipse. Tangent lines to parabolas, ellipses and hyperbolas in the form of families of folds are shown to create conic sections in unique ways. The equations of these tangent lines to conic sections and their equations can be found without using calculus. The equations of the tangent lines are also used to prove the bisection theorem for all conic sections and prove uniqueness for the bisection theorem in connection to conic sections. / text

A common characteristic of the theoretical developments within the field of social media marketing is that activities to which consumers devote themselves in social media settings shift power from firms to consumers. Extant literature has therefore analysed the practices of consumers within social media and their potential implications for marketing. The current state of social media, however, suggests that these settings are undergoing a process of transformation. Although social media were initially characterised as non-commercial in nature, firms have started to manage interactions within these digital landscapes. From initially being characterised by its social base, this development implies that social media have become increasingly commercialised. The aim of this dissertation is to expand the literature on social media by describing the process through which they evolve from their initially social character to a commercial utility. More specifically, it seeks to develop a conceptual framework that captures the role of marketing processes that lead to the commercialisation of these spheres. This is done mainly through a netnographic study of the Swedish fashion blogosphere in order to explain how and why consumers and professionals interact, organise, create and appropriate commercial values in the fashion blogosphere. Drawing on theory of spheres, this dissertation proposes a sphereological understanding of social media that expands the role of marketing. It is suggested that social media may be understood as a collection of micro-spheres that, together, comprise a densely connected foam of spatiality and place. In these spheres, consumers, together with commercial actors, take part in practices that become increasingly commercial. In that sense, marketing takes the roles of navigating social media in search of symbolic meanings of value, and of affecting, negotiating and redefining atmospheres of places in the social media landscape. / <p>At the time of the doctoral defense the following paper was unpublished and had the status as follows. Paper 2: Accepted.</p>

Inaug.-Diss.--Breslau. / Lebenslauf. "Literaturverzeichnis": p. [vii]-ix.

Inaug.-Diss.--Breslau. / Lebenslauf. "Literaturverzeichnis": p. [vii]-ix.

Gel-precipitated (U, Th) spheres produced at AERE Harwell, were investigated to study the development of the structure of the gel spheres at various stages of production. Various parameters including surface area, true (matrix) and geometric densities, porosity, crystallite size, compliance and related properties were investigated. A careful examination of whole and cleaved spheres by Scanning Electron Microscope was also carried out. The xerogel spheres were debonded in a tubular furnace in an atmosphere of CO[2] to remove or decompose the gelling agent (polymer) and other volatiles which might be present. The isothermal and constant-rate-of-heating (CRH) sintering behaviour of partially and fully debonded spheres were studied. In the latter work the shrinkage data of a batch of spheres were obtained from geometric (Hg) density measurements instead of the conventional dilatometric method used for pellets. The study has shown that ageing and heavy metal composition have a substantial influence on the structure of the debonded spheres, the rate of sintering, and the microstructure of the sintered products. Ageing and increasing amount of thorium generally retards sintering. Partially debonded (to 750&deg;C) spheres sinter faster than fully debonded spheres and the former also develop larger grains on sintering. Gel-precipitation is a versatile technique which can be used to produce spheres which sinter to > 98% of the theoretical density at a comparatively low temperature (&ap; 1400 C). Grain-boundary diffusion was found to be the probable dominant material transport mechanism in the sintering of (U, 30% Th)O[2].