{2p_\pi}-{2p_\sigma} crossing in heavy symmetric ion-atom collisions: I. Level structure

Ab initio self-consistent DFS calculations are performed for five different symmetric atomic systems from Ar-Ar to Pb-Pb. The level structure for the {2p_\pi}-{2p_\sigma} crossing as function of the united atomic charge Z_u is studied and interpreted. Manybody effects, spin-orbit splitting, direct relativistic effects as well as indirect relativistic effects are differently important for different Z_u. For the I-I system a comparison with other calculations is given.

Synthesis of N-amino compounds and C2 symmetric N-amino compounds and transformation into aziridines using olefins

Aziridine, Stickstoffanaloga der Epoxide, können regio- und stereoselektive Ringöffnungsreaktionen eingehen, wodurch ihnen als „building blocks“ in der Organischen Synthese eine große Bedeutung zukommt. In dieser Arbeit wurden unterschiedliche N-Aminoverbindungen synthetisiert sowie die Anwendungsmöglichkeit dieser Hydrazinderivate als Stickstoffquellen in Aziridinierungen von Olefinen untersucht. In der vorliegenden Dissertation wurde eine neue Methode zur Darstellung von N-Aminosuccinimid entwickelt und die Einsatzmöglichkeit als Stickstoffquelle in Aziridinierungsreaktionen in einer Reihe von Umsetzungen mit funktionalisierten ebenso wie mit nicht-funktionalisierten Olefinen demonstriert. Die ableitbaren Aziridine wurden hierbei in Ausbeuten von bis zu 80 % erhalten. In der Aziridinierungsreaktion von N-Aminosuccinimid mit 4,7-Dihydro-2-isopropyl-1,3-dioxepin resultieren bicyclische Aziridinierungsprodukte, die als endo/exo-Isomere in einem 1:1-Verhältnis anfallen. Es ist in dieser Arbeit gelungen, die Isomere in guten Ausbeuten zu erhalten, sie säulenchromatographisch zu trennen und ihre Konfiguration im festen Zustand mittels Kristallstrukturanalyse eindeutig zu bestimmen. Enantiomerenangereicherte Olefine, wie z. B. in 2-Position alkylsubstituierte 5-Methyl-4H-1,3-dioxine mit Enantiomerenüberschüssen von 92% ee liefern in der Aziridinierung mit N-Aminosuccinimid und Iodosylbenzol ein 4-Methyl-1,3-oxazolidin-4-carbaldehydderivat in einer zweistufigen Reaktion- der Aziridinierung und einer Umlagerung- ein 4-Methyl-1,3-oxazolidin-4-carbaldehydderivat. Für die Diastereoselektivität des Aziridinierungsschrittes wurde 65 % de bestimmt. In einer neuen Synthese über zwei Stufen ausgehend von (+)-3,4-Dimethoxysuccinanhydrid konnte ein chiraler Stickstoffüberträger - (+)-N-Amino-3,4-dimethoxysuccinimid - in Ausbeuten bis zu 86 % synthetisiert. Die Umsetzung dieser optisch aktiven Stickstoffquelle mit einer Vielzahl prochiraler Alkene führt zu diastereomeren Aziridinen in Ausbeuten bis zu 65% und Diastereoselektivitäten von bis zu 66% de. Anhand ausgewählter Verbindungen konnten die Absolutkonfigurationen der Reaktionsprodukte mittels Kristallstrukturanalyse eindeutig geklärt werden.

Finding Spaces for Urban Food Production – Matching Spatial and Stakeholder Analysis with Urban Agriculture Approaches in the Urban Renewal Area of Dortmund-Hörde, Germany

Using the case of an economically declined neighbourhood in the post-industrial German Ruhr Area (sometimes characterized as Germany’s “Rust Belt”), we analyse, describe and conclude how urban agriculture can be used as a catalyst to stimulate and support urban renewal and regeneration, especially from a socio-cultural perspective. Using the methodological framework of participatory action research, and linking bottom-up and top-down planning approaches, a project path was developed to include the population affected and foster individual responsibility for their district, as well as to strengthen inhabitants and stakeholder groups in a permanent collective stewardship for the individual forms of urban agriculture developed and implemented. On a more abstract level, the research carried out can be characterized as a form of action research with an intended transgression of the boundaries between research, planning, design, and implementation. We conclude that by synchronously combining those four domains with intense feedback loops, synergies for the academic knowledge on the potential performance of urban agriculture in terms of sustainable development, as well as the benefits for the case-study area and the interests of individual urban gardeners can be achieved.

On the V(subscript gamma) Dimension for Regression in Reproducing Kernel Hilbert Spaces

This paper presents a computation of the $V_gamma$ dimension for regression in bounded subspaces of Reproducing Kernel Hilbert Spaces (RKHS) for the Support Vector Machine (SVM) regression $epsilon$-insensitive loss function, and general $L_p$ loss functions. Finiteness of the RV_gamma$ dimension is shown, which also proves uniform convergence in probability for regression machines in RKHS subspaces that use the $L_epsilon$ or general $L_p$ loss functions. This paper presenta a novel proof of this result also for the case that a bias is added to the functions in the RKHS.

Preconditioning and iterative solution of symmetric indefinite linear systems arising from interior point methods for linear programming

We study the preconditioning of symmetric indefinite linear systems of equations that arise in interior point solution of linear optimization problems. The preconditioning method that we study exploits the block structure of the augmented matrix to design a similar block structure preconditioner to improve the spectral properties of the resulting preconditioned matrix so as to improve the convergence rate of the iterative solution of the system. We also propose a two-phase algorithm that takes advantage of the spectral properties of the transformed matrix to solve for the Newton directions in the interior-point method. Numerical experiments have been performed on some LP test problems in the NETLIB suite to demonstrate the potential of the preconditioning method discussed.

Using zappers in Common Learning Spaces (Windows XP)

This resource is now obsolete and has been replaced by http://www.edshare.soton.ac.uk/5920/ This PowerPoint is an animated step-by-step guide that shows tutors how to use zappers in a teaching session. It covers starting the PC, distributing the zappers, plugging in the receiver, starting the software, running the presentation and managing voting, saving data at the end and collecting the handsets. It takes around 5 minutes to view.

Large Scale Structure of Metric Spaces

How the mathematical concept of Coarse Geometries is useful to analysing the Web

The cultural magazines as spaces of resistence in the lasta argentinian militar dictatorship. From the “El Expreso Imaginario” to “El Porteño”, 1976 – 1983

Although they were a few, there were places during the military dictatorship, which produced innovative cultural goods, in continuity with experiences of the artistic avant-garde in the sixties. Alongside the political and military repression  they could articulate in their environment groups identified with alternative aesthetic  codes, in opposition to the dominant culture in the period. The first one of the aces  we examine in the article, El Expreso Imaginario is a privileged place where we may regard the origins of the traits of that social space. Towards the end of  the dictatorship, another one like El Porteño, marks a new era, even if we can  establish various continuities with the first one. The circulation places of these ideas and practices were often taking place in cellars and other hiding places. Is  that because they take the literal sense of underground in the eighties to groups  who having been part of that story or not, were willing to receive his inspiring legacy. Between both magazines we   fer identifies the transition from one state of the field to another, identifying the evolution of these zone of the culture field.

Are the maximum hardness and minimum polarizability principles always obeyed in nontotally symmetric vibrations?

An overview is given on a study which showed that not only in chemical reactions but also in the favorable case of nontotally symmetric vibrations where the chemical and external potentials keep approximately constant, the generalized maximum hardness principle (GMHP) and generalized minimum polarizability principle (GMPP) may not be obeyed. A method that allows an accurate determination of the nontotally symmetric molecular distortions with more marked GMPP or anti-GMPP character through diagonalization of the polarizability Hessian matrix is introduced

Delineating difference and spaces of resistance : reading the Nana’s Silence in Rosario Castellanos’ ''Balún Canán''

A escritora mexicana Rosario Castellanos incorpora silêncios em suas obras de uma forma que permite ao leitor a questionar o próprio significado da agência e da natureza da subjetividade de uma protagonista feminina. Silêncios tendem a criar brechas no texto, iluminando as diferenças sociais e raciais que a narração em primeira pessoa foge. Além disso, é revelado que o sujeito se imagina em oposição ao silêncio de mulheres menos privilegiadas, e que realmente não existe um local em que o subalterno pode falar. Este projecto se centra em seu romance Balún Canan (1957), em que a babá Indígena de uma menina complica o desejo de ascender dentro da estrutura patriarcal da sua família mais privilegiada, como a menina descobre que o que faria sua vida confortável é a causa da subjugação de sua “outra mãe.” O texto é desenvolvido em torno de um desejo de falar a partir das margens, e há um esforço claro para dar voz aos subalternos. No entanto, a relação entre a menina e sua babá não é nem romântica nem idealizada; a presença da mulher colonizada resiste a marginalização e ressalta que está sendo coberto no processo de desenvolvimento individual. Ansiedadesurge dentro da narração da menina como ela percebe seu privilégio como membro da classe latifundiária, e a escrita navega entre diferentes manifestações de silêncio: o silenciamento da babá em uma replicação de violência colonial, e a manutenção do silêncio como uma barreira respeitosa.

Dunford-Pettis properties, Hilbert spaces and projective tensor products

We study complete continuity properties of operators onto ℓ2 and prove several results in the Dunford–Pettis theory of JB∗-triples and their projective tensor products, culminating in characterisations of the alternative Dunford–Pettis property for where E and F are JB∗-triples.

Spin spaces and positive decomposition of linear maps on ordered Banach spaces

Spin factors and generalizations are used to revisit positive generation of B(E, F), where E and F are ordered Banach spaces. Interior points of B(E, F)+ are discussed and in many cases it is seen that positive generation of B(E, F) is controlled by spin structure in F when F is a JBW-algebra.