Small bound for birational automorphism groups of algebraic varieties (with an Appendix by Yujiro Kawamata)

We give an effective upper bound of |Bir(X)| for the birational automorphism group of an irregular n-fold (with n = 3) of general type in terms of the volume V = V(X) under an ''albanese smoothness and simplicity'' condition. To be precise, |Bir(X)| < d_3 V^{10}. An optimum linear bound |Bir(X)|-1 < (1/3)(42)^3 V is obtained for those 3-folds with non-maximal albanese dimension. For all n > 2, a bound |Bir(X)| < d_n V^{10} is obtained when alb_X is generically finite, alb(X) is smooth and Alb(X) is simple.Comment: Mathematische Annalen, to appea

Section Extension from Hyperbolic Geometry of Punctured Disk and Holomorphic Family of Flat Bundles

The construction of sections of bundles with prescribed jet values plays a fundamental role in problems of algebraic and complex geometry. When the jet values are prescribed on a positive dimensional subvariety, it is handled by theorems of Ohsawa-Takegoshi type which give extension of line bundle valued square-integrable top-degree holomorphic forms from the fiber at the origin of a family of complex manifolds over the open unit 1-disk when the curvature of the metric of line bundle is semipositive. We prove here an extension result when the curvature of the line bundle is only semipositive on each fiber with negativity on the total space assumed bounded from below and the connection of the metric locally bounded, if a square-integrable extension is known to be possible over a double point at the origin. It is a Hensel-lemma-type result analogous to Artin's application of the generalized implicit function theorem to the theory of obstruction in deformation theory. The motivation is the need in the abundance conjecture to construct pluricanonical sections from flatly twisted pluricanonical sections. We also give here a new approach to the original theorem of Ohsawa-Takegoshi by using the hyperbolic geometry of the punctured open unit 1-disk to reduce the original theorem of Ohsawa-Takegoshi to a simple application of the standard method of constructing holomorphic functions by solving the d-bar equation with cut-off functions and additional blowup weight functions

E-commerce transactions in a virtual environment: Virtual transactions

E-commerce is a fundamental method of doing business, such that for a firm to say it is trading at all in the modern market-place it must have some element of on-line presence. Coupled with this is the explosion of the "population" of Massively Multiplayer On-line Role Playing Games and other shared virtual environments. Many suggest this will lead to a further dimension of commerce: virtual commerce. We discuss here the issues, current roadblocks and present state of an e-commerce transaction carried out completely within a virtual environment; a virtual transaction. Although technically such transactions are in a sense trivial, they raise many other issues in complex ways thus making V-transactions a highly interesting cross-disciplinary issue. We also discuss the social, ethical and regulatory implications for the virtual communities in these environments of such v-transactions, how their implementation affects the nature and management of a virtual environment, and how they represent a fundamental merging of the real and virtual worlds for the purpose of commerce. We highlight the minimal set of features a v-transaction capable virtual environment requires and suggest a model of how in the medium term they could be carried out via a methodology we call click-through, and that the developers of such environments will need to take on the multi-modal behavior of their users, as well as elements of the economic and political sciences in order to fully realize the commercial potential of the v-transaction. © 2012 Springer Science+Business Media, LLC

Exploiting bacterial DNA gyrase as a drug target: current state and perspectives

DNA gyrase is a type II topoisomerase that can introduce negative supercoils into DNA at the expense of ATP hydrolysis. It is essential in all bacteria but absent from higher eukaryotes, making it an attractive target for antibacterials. The fluoroquinolones are examples of very successful gyrase-targeted drugs, but the rise in bacterial resistance to these agents means that we not only need to seek new compounds, but also new modes of inhibition of this enzyme. We review known gyrase-specific drugs and toxins and assess the prospects for developing new antibacterials targeted to this enzyme

A Conceptual Framework for Assessing Development Programmes for Change Agents, CALT Working Paper 1999-1

Deregulation, unstable financial markets, increasing global competition, advances in information and communication technologies- these are only a few of the conditions driving the escalating pace of change evident within business communities today. Harnessing an organisation of people who thrive on the challenges of ambiguity, complexity and uncertainty and who can successfully and rapidly implement strategic and operational changes, is seen as a differentiating core competence for competitive companies. Today, technology and information systems are usually key enabling factors when organisations embrace major change strategies, but it is becoming evident that to leverage strategic opportunities from advances in information systems and enabling technologies such as the internet, intranets and e-commerce, good change management practices must be adopted. In this paper we derive a framework for assessing training programmes for change agents, based on an extensive review of the literature on change management models and the skills and competencies necessary to manage change successfully. This framework provides a basis for identifying pedagogical objectives for teaching change management to executives, IT specialists, change agents and change recipients. As an illustration, the framework is applied to evaluate the effectiveness of a computer based multimedia simulation, a training tool known as the EIS Simulation, in satisfying these pedagogical objectives. 1

High performance hybrid construction system with timber and steel

In nur fünf Monaten wurde in Lenzburg (CH) mit einem neu ent-wickelten Hochleistungs-Hybridbausystem ein energieeffizien-tes Mehrfamilienhaus mit 20 preisgünstigen Mietwohnungen realisiert.Das Prinzip des Hochleistungs-Hybridbausystems sieht bezugs-fertig hergestellte kubische Wohnraummodule aus einer Holz-leichtbaukonstruktion vor, welche auf der Baustelle in eine vor-gängig montierte Stahlskelettkonstruktion eingefügt werden. Im Gegensatz zur üblichen Raummodulbauweise, bei der die Module aufeinandergestapelt werden, konnten durch das Ent-wurfsprinzip der sich selbst tragenden Holzbaumodule die Wanddicken reduziert und damit wesentlich materialoptimiert werden. Die Stahlskelettkonstruktion ermöglicht, die Wanddi-cke der Stahlhohlprofile optimal auf die Anzahl der Geschosse anzupassen. Die Stahlskelettstützen bleiben in ihren Außen-abmessung bei vier- bis achtgeschossigen Gebäuden immer gleich und ermöglichen eine max. Standardisierung bei der Detailausbildung. Eines der Schlüsselelemente der Entwick-lungsarbeit war die konsequent ausgebildete Schallentkopp-lung zwischen Wohnraummodul und Stahlskelett. Sämtliche Auflagerdetails, Stabilisierungsanschlüsse und Verbindungen zwischen Modul und Skelett sind durch Elastomerlager schall-technisch entkoppelt.In just five months, an energy-efficient apartment building with 20 low-priced rental apartments was built in Lenzburg (Switzer-land) using a newly developed high-performance hybrid con-struction system.The principle of the high-performance hybrid construction system envisages cubic living space modules made of a light-weight timber construction and manufactured ready to move, which are inserted into a previously assembled steel skeleton construction on site. In contrast to the usual room module con-struction method, in which the modules are stacked on top of each other, the present design principle of the self-supporting timber construction modules allows a reduction of wall thick-nesses and thus a considerable optimization of material use. The steel skeleton construction enables an optimal adaptation of wall thickness of the steel hollow sections to the number of floors. The external dimensions of the steel skeleton support remain always the same for four to eight story buildings and allow a maximum standardization in the detail design. One of the key elements of the development work is the consistently developed sound decoupling between the living space module and the steel skeleton. All support details, stabilisation connec-tions and connections between module and skeleton are sound decoupled by elastomer layers