Acceleration field of a Universe modeled as a mixture of scalar and matter fields

A model of the Universe as a mixture of a scalar (inflaton or rolling tachyon from the string theory) and a matter field (classical particles) is analyzed. The particles are created at the expense of the gravitational energy through an irreversible process whereas the scalar field is supposed to interact only with itself and to be minimally coupled with the gravitational field. The irreversible processes of particle creation are related to the non-equilibrium pressure within the framework of the extended (causal or second-order) thermodynamic theory. The scalar field (inflaton or tachyon) is described by an exponential potential density added by a parameter which represents its asymptotic value and can be interpreted as the vacuum energy. This model can simulate three phases of the acceleration field of the Universe, namely,(a) an inflationary epoch with a positive acceleration followed by a decrease of the acceleration field towards zero, (b) a past decelerated period where the acceleration field decreases to a maximum negative value followed by an increase towards zero, and (c) a present accelerated epoch. For the energy densities there exist also three distinct epochs which begin with a scalar field dominated period followed by a matter field dominated epoch and coming back to a scalar field dominated phase.Comment: 9 pages, 2 figures, to be published in General Relativity and Gravitatio

Interface Unbinding in Structured Wedges

The unbinding properties of an interface near structured wedges are investigated by discrete models with short range interactions. The calculations demonstrate that interface unbinding take place in two stages: $i$) a continuous filling--like transition in the pure wedge--like parts of the structure; $ii$) a conclusive discontinuous unbinding. In 2$D$ an exact transfer matrix approach allows to extract the whole interface phase diagram and the precise mechanism at the basis of the phenomenon. The Metropolis Monte Carlo simulations performed in 3$D$ reveal an analogous behavior. The emerging scenario allows to shed new light onto the problem of wetting of geometrically rough walls.Comment: 5 pages, 5 figures, to appear in Phys. Rev.

Financial Reform and Development in the Philippines, 1980-1997: Imperatives, Performance and Challenges

This paper discusses financial reform and development in the Philippines during the past one and a half decades and the challenges facing the financial sector in the light of greater international financial integration. Issues on prudential regulation and how it can be improved and strengthened are presented. Key lessons from the Philippines and Southeast Asian experience are also discussed.Asian financial crisis, financial sector, financial liberalization, financial integration

Financial Reform and Development in the Philippines, 1980-1997: Imperatives, Performance and Challenges

This paper discusses financial reform and development in the Philippines during the past one and a half decades and the challenges facing the financial sector in the light of greater international financial integration. Issues on prudential regulation and how it can be improved and strengthened are presented. Key lessons from the Philippines and Southeast Asian experience are also discussed.Asian financial crisis, financial sector, financial liberalization, financial integration

Twisted Mass Finite Volume Effects

We calculate finite volume effects on the pion masses and decay constant in twisted mass lattice QCD (tmLQCD) at finite lattice spacing. We show that the lighter neutral pion in tmLQCD gives rise to finite volume effects that are exponentially enhanced when compared to those arising from the heavier charged pions. We demonstrate that the recent two flavour twisted mass lattice data can be better fitted when twisted mass effects in finite volume corrections are taken into account.Comment: 17 pages, revte

Microinsurance: Does Traditional Regulation Apply?

Microinsurance--insurance services for low-income households--has emerged as a phenomenon in recent years. This Policy Notes draws attention to the need for an effective regulatory and supervision framework for said phenomenon to assure access of low-income households to insurance and to maintain the soundness of the insurance industry.microinsurance, mutual benefit associations

Rhodoliths and rhodolith beds

Rhodolith (maërl) beds, communities dominated by free living coralline algae, are a common feature of subtidal environments worldwide. Well preserved as fossils, they have long been recognized as important carbonate producers and paleoenvironmental indicators. Coralline algae produce growth bands with a morphology and chemistry that record environmental variation. Rhodoliths are hard but often fragile, and growth rates are only on the order of mm/yr. The hard, complex structure of living beds provides habitats for numerous associated species not found on otherwise entirely sedimentary bottoms. Beds are degraded locally by dredging and other anthropogenic disturbances, and recovery is slow. They will likely suffer severe impacts worldwide from the increasing acidity of the ocean. Investigations of rhodolith beds with scuba have enabled precise stratified sampling that has shown the importance of individual rhodoliths as hot spots of diversity. Observations, collections, and experiments by divers have revolutionized taxonomic studies by allowing comprehensive, detailed collection and by showing the large effects of the environment on rhodolith morphology. Facilitated by in situ collection and calibrations, corallines are now contributing to paleoclimatic reconstructions over a broad range of temporal and spatial scales. Beds are particularly abundant in the mesophotic zone of the Brazilian shelf where technical diving has revealed new associations and species. This paper reviews selected past and present research on rhodoliths and rhodolith beds that has been greatly facilitated by the use of scuba

In the opponent's shoes: increasing the behavioral validity of attackers' judgments in counterterrorism models

A key objective for policymakers and analysts dealing with terrorist threats is trying to predict the actions that malicious agents may take. A recent trend in counterterrorism risk analysis is to model the terrorists' judgments, as these will guide their choices of such actions. The standard assumptions in most of these models are that terrorists are fully rational, following all the normative desiderata required for rational choices, such as having a set of constant and ordered preferences, being able to perform a cost-benefit analysis of their alternatives, among many others. However, are such assumptions reasonable from a behavioral perspective? In this article, we analyze the types of assumptions made across various counterterrorism analytical models that represent malicious agents' judgments and discuss their suitability from a descriptive point of view. We then suggest how some of these assumptions could be modified to describe terrorists' preferences more accurately, by drawing knowledge from the fields of behavioral decision research, politics, philosophy of choice, public choice, and conflict management in terrorism. Such insight, we hope, might help make the assumptions of these models more behaviorally valid for counterterrorism risk analysis