Gluing of Branched Surfaces by Sewing of Fermionic String Vertices

We glue together two branched spheres by sewing of two Ramond (dual) two-fermion string vertices and present a rigorous analytic derivation of the closed expression for the four-fermion string vertex. This method treats all oscillator levels collectively and the obtained answer verifies that the closed form of the four vertex previously argued for on the basis of explicit results restricted to the first two oscillator levels is the correct one.Comment: 20 pages + 5 figures as eps-file

The Twisted String Vertex Algorithm Applied to the Z2Z_2-Twisted Scalar String Four Vertex

Recently an algorithm was found by means of which one can calculate terms at arbitrary oscillator level in the four-Ramond vertex obtained by sewing. Here we show that this algorithm is applicable also to the case of ${\bf Z}_2$-twisted scalars and derive the full propagator for scalars on the Riemann sphere with two branch cuts. The relation to similar results previously derived in the literature by other means is discussed briefly.Comment: 18 pages (LaTeX), G\"oteborg ITP 94-

Rezension zu „Recht verstehen. Wie Laien, Juristen und Versicherungsagenten die ‚Riester-Rente‘ interpretieren“ von Angelika Becker und Wolfgang Klein. Berlin, Akademie Verlag 2008.

Rezension zu „Recht verstehen. Wie Laien, Juristen und Versicherungsagenten die ‚Riester-Rente‘ interpretieren“ von Angelika Becker und Wolfgang Klein; Berlin 2008: Akademie Verlag: „Es gibt in der Literatur keinen Mangel an umfangreichen und generellen Darstellungen zu Sprache und Verstehen, auch nicht auf dem Gebiet des Rechts; dagegen fehlt es an Darlegungen dazu, wie man empirisch den Verstehensprozess untersuchen kann. Diese Lücke füllt das Buch.“   Review of „Recht verstehen. Wie Laien, Juristen und Versicherungsagenten die ‚Riester-Rente‘ interpretieren“ von Angelika Becker und Wolfgang Klein; Berlin 2008: Akademie Verlag: „In the current literature, there is no lack of general and detailed works dealing with language and comprehension, including in the area of law; there is, however, a dearth of empirical studies dealing with cognitive process analysis. This book fills that gap.“   Compte rendu de „Recht verstehen. Wie Laien, Juristen und Versicherungsagenten die ‚Riester-Rente‘ interpretieren“ von Angelika Becker und Wolfgang Klein; Berlin 2008: Akademie Verlag: „La littérature spécialisée foisonne de développements sur la relation „langue et compréhension“, y compris dans le domaine du droit. Par contre peu d’ouvrages proposent une approche empirique du processus de compréhension. Le présent ouvrage tente de combler cette lacune.“Review of „Recht verstehen. Wie Laien, Juristen und Versicherungsagenten die ‚Riester-Rente‘ interpretieren“ von Angelika Becker und Wolfgang Klein; Berlin 2008: Akademie Verlag: „In the current literature, there is no lack of general and detailed works dealing with language and comprehension, including in the area of law; there is, however, a dearth of empirical studies dealing with cognitive process analysis. This book fills that gap.“

Regenerative medicine and register studies related to bladder exstrophy

Bladder exstrophy is a rare congenital malformation affecting both boys and girls. The malformation involves the bladder, the urethra, genitalia, and pelvis. The child presents with a defect of the lower abdominal wall exposing an open bladder. In this thesis, the field of regenerative medicine is explored with the aim of improving the surgical treatment of malformations where there is a lack of tissue, such as bladder exstrophy when a bladder conduit is sometimes needed for bladder catheterization. The thesis also includes register studies for further understanding of the prevalence, morbidities, the quality of life, and risk factors associated with bladder exstrophy. Studies I and II were conducted in a porcine animal model with the aim of constructing a functional autologous bladder conduit to be used for catheterization. Both studies were aimed at using regenerative medicine techniques with minimal ex vivo handling. Bladder tissue was obtained and minced for autologous tissue transplantation in order to analyze the regenerative capacity of the mucosa, the urothelium, and the muscle, the detrusor. Animals were housed up to five weeks post transplantation. In Study I, functional bladder emptying tests were performed by catheterization through the neo-regenerated conduit and CT scans were used for anatomical evaluation. In Study II, detrusor muscle expansion was studied in vitro and in vivo for evaluation of the regenerative capacity after mincing. In conclusion, bladder wall mincing techniques could be a valuable tool for autologous tissue expansion, which can be prepared at the operating table as a one-step surgical procedure. Study III was conducted as a matched case-control study using Swedish national populationbased registers. One-hundred-and-twenty cases of bladder exstrophy were identified between 1973 and 2011. The prevalence was 3:100 000, which was stable over time. In contrast to other publications, an equal male-to-female ratio was found. Birth descriptive data were comparable to those of controls, and bladder exstrophy occurred most often without any other major associated malformations. Congenital inguinal hernia and undescended testis were, however, more prevalent than in the general population. The only potentially associated maternal risk factor was advanced maternal age. Study IV was conducted as a matched cohort study between 1952 and 2011. We used Swedish national population–based registers to assess morbidity, mortality, and such social parameters as partnership, fertility, and education. One-hundred-and-eighty cases were identified for analyses of morbidity and mortality and 124 of these cases were individuals over 18 years of age and thus were available for further social analyses. The incidences of bladder cancer and psychiatric disorders were comparable to those of the general Swedish population. Mortality was low. Sensory neurogenic hearing disorders indicated a possible genetic association in a few cases. No differences concerning partnership could be established, but significantly fewer cases conceived biological children. The educational level was high overall, with male cases reaching a slightly lower level, and females a higher level ofthe highest level of education compared to control

Person or Place? Parametric and semiparametric estimates of intrametropolitan earnings variation

Some scholars have attributed earnings differences among locations to labor market conditions ("place effects") whereas others have focused on the skill level of residents ("person effects"). We estimate a variety of selection models in an effort to detect differences in labor market conditions while controlling for differences in skill levels. We maintain the assumption that there are no barriers to mobility within a metropolitan area for highly educated white men, which implies that intra-urban differences for this group reflect sorting by skill and earnings rather than real wage differences for equally productive workers. This prediction allows us to reject several conventional parametric selection models. We estimate a semiparametric selection model that yields strong evidence that, for less educated white men, the apparent suburban earnings premium is due to sorting rather than labor market differences.

Theory of the Bloch Oscillating Transistor

The Bloch oscillating transistor (BOT) is a device, where single electron current through a normal tunnel junction can be used to enhance Cooper pair current in a mesoscopic Josephson junction leading to signal amplification. In this paper we develop a theory, where the BOT dynamics is described as a two-level system. The theory is used to predict current-voltage characteristics and small-signal response. Transition from stable operation into hysteretic regime is studied. By identifying the two-level switching noise as the main source of fluctuations, the expressions for equivalent noise sources and the noise temperature are derived. The validity of the model is tested by comparing the results with simulations.Comment: 11 pages, 8 figure

Towards goal-based autonomic networking

The ability to quickly deploy and efficiently manage services is critical to the telecommunications industry. Currently, services are designed and managed by different teams with expertise over a wide range of concerns, from high-level business to low level network aspects. Not only is this approach expensive in terms of time and resources, but it also has problems to scale up to new outsourcing and/or multi-vendor models, where subsystems and teams belong to different organizations. We endorse the idea, upheld among others in the autonomic computing community, that the network and system components involved in the provision of a service must be crafted to facilitate their management. Furthermore, they should help bridge the gap between network and business concerns. In this paper, we sketch an approach based on early work on the hierarchical organization of autonomic entities that possibly belong to different organizations. An autonomic entity governs over other autonomic entities by defining their goals. Thus, it is up to each autonomic entity to decide its line of actions in order to fulfill its goals, and the governing entity needs not know about the internals of its subordinates. We illustrate the approach with a simple but still rich example of a telecom service