MODELING THE BIOECONOMICS IMPACTS OF CO-MANAGEMENT IN CHILEAN ARTISANAL FISHERIES

The failure of the centralized management system and the intense over-exploitation of benthonic resources along the Chilean coast motivated the design and implementation of an innovative co-management policy in 1999. Although its positive effects have already been recognized at biological and organizational level, doubts have been posed with regards to its economic sustainability. In this paper, we present a bio-economic evaluation at national level for one of the most important and valuable benthonic resources, the Loco ecosystem. A dynamic simulation model is developed in order to compare and evaluate the effectiveness of the traditional centralized management and the co-management system recently implemented in Chile. The results show that the amount of captures and effort devoted during the centralized management period were significantly underestimated due to the existence of illegal captures. On the other side, the results reveal that, after a fearful beginning, the values for revenues, capture and stock were larger than those that would have been obtained in case the former centralized system had persisted.natural resource modeling, marine policy, co-management policy, artisanal fisheries management, Territorial Use Right Fisheries, Industrial Organization, Resource /Energy Economics and Policy,

Magnetic Collapse of a Neutron Gas: No Magnetar Formation

A degenerate neutron gas in equilibrium with a background of electrons and protons in a magnetic field exerts its pressure anisotropically, having a smaller value perpendicular than along the magnetic field. For critical fields the magnetic pressure may produce the vanishing of the equatorial pressure of the neutron gas, and the outcome could be a transverse collapse of the star. This fixes a limit to the fields to be observable in stable pulsars as a function of their density. The final structure left over after the implosion might be a mixed phase of nucleons and meson ($\pi^{\pm,0},\kappa^{\pm,0}$) condensate (a strange star also likely) or a black string, but no magnetar at all.Comment: 5 pages, 1 latex file, 1 encapsulated figure. Submitted to Physical Review Letters (24/11/2000

A study of co-movements between USA and Latin American stock markets: a cross-bicorrelations perspective

In this paper we use the Brooks and Hinich cross-bicorrelation test in order to uncover nonlinear dependence periods between USA Standard and Poor 500 (SP500), used as benchmark, and six Latin American stock markets indexes: Mexico (BMV), Brazil (BOVESPA), Chile (IPSA), Colombia (COLCAP), Peru (IGBVL) and Argentina (MERVAL). We have found windows of nonlinear dependence and co-movement between the SP500 and the Latin American stock markets, some of which coincide with periods of crisis, giving way to a possible contagion or interdependence interpretation.Comment: Working paper, 9 page

Magnetic collapse of a neutron gas: Can magnetars indeed be formed

A relativistic degenerate neutron gas in equilibrium with a background of electrons and protons in a magnetic field exerts its pressure anisotropically, having a smaller value perpendicular than along the magnetic field. For critical fields the magnetic pressure may produce the vanishing of the equatorial pressure of the neutron gas. Taking it as a model for neutron stars, the outcome could be a transverse collapse of the star. This fixes a limit to the fields to be observable in stable neutron star pulsars as a function of their density. The final structure left over after the implosion might be a mixed phase of nucleons and meson condensate, a strange star, or a highly distorted black hole or black "cigar", but no any magnetar, if viewed as a super strongly magnetized neutron star. However, we do not exclude the possibility of a supersotrong magnetic fields arising in supernova explosions which lead directly to strange stars. In other words, if any magnetars exist, they cannot be neutron stars.Comment: 15 pages, 3 figures. European Physical Journal C in pres

Magnetized strange quark matter and magnetized strange quark stars

Strange quark matter could be found in the core of neutron stars or forming strange quark stars. As is well known, these astrophysical objects are endowed with strong magnetic fields which affect the microscopic properties of matter and modify the macroscopic properties of the system. In this paper we study the role of a strong magnetic field in the thermodynamical properties of a magnetized degenerate strange quark gas, taking into account beta-equilibrium and charge neutrality. Quarks and electrons interact with the magnetic field via their electric charges and anomalous magnetic moments. In contrast to the magnetic field value of 10^19 G, obtained when anomalous magnetic moments are not taken into account, we find the upper bound B < 8.6 x 10^17 G, for the stability of the system. A phase transition could be hidden for fields greater than this value.Comment: 9 pages, 9 figure

Real Time Digital Filter for a Front-End Electronics in Dark Matter and Neutrino Measurements

This paper presents real-time digital filter algorithms to be applied within dark matter and neutrino measurements. The digital signal processing algorithm implements a trapezoidal pulse-shaper programmed on FPGA at 125 MHz. The real-time filter algorithm enhances the SNR of a digitized signal from a photo detection module (SiPM, cryogenic front-end electronics & 14-bits ADC). The trapezoidal filter upgrades the signal to noise ratio (SNR) from 10.4 to 15.4 with a total increment of 50%. The total on-chip power is 0.198 W

DETECTION OF MYCOTOXINS USING SURFACE-ENHANCED RAMAN SPECTROSCOPY

Mycotoxins are toxic metabolites produced by fungus that can be parasites or saprophytes of crops or livestock forage. Consumer demand for plant-based foods and interest in animal-based foods originating from animals fed plant-based feed has been on the rise. Therefore, monitoring mycotoxins occurring in the food supply is more critical than ever. The goal of this project is to improve surface-enhanced Raman spectroscopy’s (SERS) ability to identify and detect mycotoxins using label-free SERS substrates. Two simple approaches were designed to enhance the detection of mycotoxins produced by the Aspergillus and Penicillium genera, ochratoxin A and aflatoxin B1. Ochratoxin A was successfully detected in wine samples spiked with the mycotoxin in a range of 0.01 to 1 ppm using a facile solvent-mediated extraction that showed the key role that the food matrix can play on the SERS substrate performance. The detection of aflatoxin B1’ SERS signals using bare gold nanoparticles was enhanced with the addition of human serum albumin (HSA) as a mediating molecule. A combination of the HSA-mediated protocol and a liquid-liquid extraction (LLE) method allows the detection of up to 2 ppb of AFB1 in compound feedstuff samples. Additionally, a simple SERS protocol applied to Aspergillus flavus grown in liquid and solid medium showed the technique’s capacity to classify between aflatoxigenic and non-aflatoxigenic species. Raman spectroscopy, SERS, Infrared Spectroscopy (IR) and surface-enhanced infrared absorption spectroscopy (SEIRAS) showed differences yet potential complementarity in their ability to identify mycotoxins produced by the Fusarium genus, deoxynivalenol and fumonisin B1