The Route towards the ultimate network topology

In this talk I will try to summarize our quest for a realizable network topology that optimizes performance, cost, power consumption and partitionability. We have explored Fat Trees, Dragonflies, variations of dragonflies, Orthogonal Fat Trees, multi-layer HyperX's, Multi-layer Full Meshes and close-to Moore's (graph) bound topologies in an attempt to decide, with the best routing we could find, for a reasonable task-placement, and for a collection of workloads (synthetic and real-world), which topology to choose. Whereas a final decision for a single 'ultimate' topology remains elusive, the route towards it took us to unexpected paths that lead to the discovery of new insights in topology design and properties and in design of routing schemes

Entanglement entropy of integer Quantum Hall states

We compute the entanglement entropy, in real space, of the ground state of the integer Quantum Hall states for three different domains embedded in the torus, the disk and the sphere. We establish the validity of the area law with a vanishing value of the topological entanglement entropy. The entropy per unit length of the perimeter depends on the filling fraction, but it is independent of the geometry.Comment: 5 pages, 2 figures, minor changes, one reference adde

Using WordNet for Building WordNets

This paper summarises a set of methodologies and techniques for the fast construction of multilingual WordNets. The English WordNet is used in this approach as a backbone for Catalan and Spanish WordNets and as a lexical knowledge resource for several subtasks.Comment: 8 pages, postscript file. In workshop on Usage of WordNet in NL

Quizbowl: Success In and Out of the Classroom, a Five Year Study

Scores of US and Canadian universities' undergraduate students participate in the SS-AAEA Quiz-bowl competition annually. Surveys of the 2001 through 2005 competition participants suggest how beneficial competition preparation and participation are in completing related university work and indicate factors which enhance chances of success in the competition.Teaching/Communication/Extension/Profession,

An introduction to financial and economic modeling for utility regulators

The most effective regulators in developing countriesare following remarkably similar approaches. The main common element across"best practice"countries is the use of relatively simple quantitative models of operators'behavior and constraints to measure the impact of regulatory decisions on some key financial and economic indicators of concern to the operators, the users, and the government. The authors provide an introduction to the design and use of these models. They draw on lessons from international experience in industrial and developing countries in ordinary or extraordinary revisions and in the context of contract renegotiations. Simplifying somewhat, these models force regulators to recognize that, in the long run, private operators need to at least cover their opportunity cost of capital, including the various types of risks specific to the country, the sector, or the projects with which they are involved. Because these variables change over time, scheduled revisions are needed to allow for adjustments in the key determinants of the rate of return of the operator. These revisions are a recognition of the fact that all these determinants-tariffs, subsidies, quality, investments, and other service obligations-are interrelated and jointly determine the rate of return. At every revision, the rules of the game for the regulator are exactly the same: to figure out the changes in the cost of capital and to adjust the variables driving the rate of return to ensure that it continues to be consistent with the cost of capital. If they can draw on reasonable data, these models do everything any financial model would do for the day-to-day management of a company but take a longer term view and include an explicit identification of the key regulatory instruments. They can monitor the consistency between cash flow generated by the business on the one hand and debt service and operational expense needs on the other to address the main concerns of the operators. They can also account for a large number of key policy factors including access and affordability concerns for various types of consumers. They generally account for the sensitivity of operators and users to various regulatory design options.Payment Systems&Infrastructure,Economic Theory&Research,Decentralization,Environmental Economics&Policies,Enterprise Development&Reform,Public Sector Economics&Finance,Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Municipal Financial Management

Survival models (in Russian)

This essay is an introduction to survival models in the context of generalized linear models. We introduce the hazard and survival functions and describe the most common censoring mechanisms and the resulting likelihood function. We discuss the main approaches to modeling waiting times, including accelerated life and proportional hazard models, with extensions to time-varying covariates and time-dependent effects. We then focus on the piece-wise exponential survival model and note its equivalence with Poisson regression models. We illustrate this approach with an application to the analysis of infant and child mortality in Colombia using survey data. We conclude with a brief discussion of discrete time models and their equivalence with logistic regression.

Mesenchymal Stem Cell Therapy in Type 1 Diabetes Mellitus and Its Main Complications: From Experimental Findings to Clinical Practice

Type 1 diabetes mellitus (T1DM) is a complex multifactorial disorder which involves a loss of self-tolerance leading to the autoimmune destruction of pancreatic β−cells. Exogenous insulin administration cannot mimic precise pancreatic β-cell regulation of glucose homeostasis, thereby leading to severe long-term complications. Pancreas or islet transplant only provides partial exogenous insulin independence and induces several adverse effects, including increased morbidity and mortality. The scientific community and diabetic patients are thus, still waiting for an effective therapy which could preserve the remaining β-cells, replenish islet mass and protect newly-generated β-cells from autoimmune destruction. Mesenchymal stem cells (MSCs) have been envisioned as a promising tool for T1DM treatment over the past few years, since they could differentiate into glucose-responsive insulin-producing cells. Their immunomodulatory and proangiogenic roles can be used to help arrest β-cell destruction, preserve residual β-cell mass, facilitate endogenous β-cell regeneration and prevent disease recurrence, thereby making them ideal candidates for the comprehensive treatment of diabetic patients. This review focuses on recent pre-clinical data supporting MSC use in regenerating β-cell mass and also in treating several T1DM-associated complications. Clinical trial results and the ongoing obstacles which must be addressed regarding the widespread use of such therapy are also discussed.Fil: Ezquer, Marcelo. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Arango Rodriguez, Martha. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; ChileFil: Giraud Billoud, Maximiliano German. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Ezquer, Fernando. Universidad del Desarrollo. Facultad de Medicina Clínica Alemana; Chil

How Attitudes of Important Stakeholder Groups Can Influence Effective Water Quality Management

Preliminary results of a survey of Lincoln Lake agricultural and non-agricultural watershed residents as well as water quality regulators/specialists suggests discrepancies exists in different groups perceptions of water quality, the sources of water pollution, and the roles of local, county, state and federal officials in meeting water quality objectives.Resource /Energy Economics and Policy, Q25, Q53, Q59,