Reserves Protect against Deforestation Fires in the Amazon

BACKGROUND: Reserves are the principal means to conserve forests and biodiversity, but the question of whether reserves work is still debated. In the Amazon, fires are closely linked to deforestation, and thus can be used as a proxy for reserve effectiveness in protecting forest cover. We ask whether reserves in the Brazilian Amazon provide effective protection against deforestation and consequently fires, whether that protection is because of their location or their legal status, and whether some reserve types are more effective than others. METHODOLOGY/PRINCIPAL FINDINGS: Previous work has shown that most Amazonian fires occur close to roads and are more frequent in El Niño years. We quantified these relationships for reserves and unprotected areas by examining satellite-detected hot pixels regressed against road distance across the entire Brazilian Amazon and for a decade with 2 El Niño-related droughts. Deforestation fires, as measured by hot pixels, declined exponentially with increasing distance from roads in all areas. Fewer deforestation fires occurred within protected areas than outside and the difference between protected and unprotected areas was greatest near roads. Thus, reserves were especially effective at preventing these fires where they are known to be most likely to burn; but they did not provide absolute protection. Even within reserves, at a given distance from roads, there were more deforestation fires in regions with high human impact than in those with low impact. The effect of El Niño on deforestation fires was greatest outside of reserves and near roads. Indigenous reserves, limited-use reserves, and fully protected reserves all had fewer fires than outside areas and did not appear to differ in their effectiveness. CONCLUSIONS/SIGNIFICANCE: Taking time, regional factors, and climate into account, our results show that reserves are an effective tool for curbing destructive burning in the Amazon

The motion of two masses coupled to a massive spring

We discuss the classical motion of a spring of arbitrary mass coupled to two arbitrary massive blocks attached at its ends. A general approach to the problem is presented and some general results are obtained. Examples for which a simple elastic function can be inferred are discussed and the normal modes and normal frequencies obtained. An approximation procedure to the evaluation of the normel frequencies in the case of uniform elastic function and mass density is also discussed.Comment: Standard Latex file plus three eps figure

Nurses\u27 Alumnae Association Bulletin, September 1958

Committee Reports Digest of Alumnae Meetings Graduation Awards - 1957 List of Wrong Addresses Marriages Necrology New Arrivals Physical Advances at Jefferson President\u27s Message School of Nursing Repor

Arranjos Institucionais das Supreme Audit Institutions E sua Relação Com a Consolidação da Democracia

A transparência e a accountability almejadas em uma democracia parlamentarista ou presidencialista visam à aproximação entre a sociedade e seus representantes eleitos, onde as Supreme Audit Institutions (SAIs) exercem papel fundamental. Sendo uma das formas de controle durante os mandatos, as Supreme Audit Institutions são órgãos que têm como uma de suas finalidades o controle daqueles que gerenciam recursos públicos, onde acabam apreciando seus atos para auxiliar naqueles que posteriormente irão julgá-los. São três os principais modelos de SAIs (Westminster, Judicial e Colegiado), em que a escolha institucional dos países tende a levar em conta os interesses a serem alcançados, podendo a forma de governo, onde os mesmos estão inseridos, influenciar nas opções a serem realizadas. A presente dissertação tem o objetivo estudar a chance de associação entre os desenhos institucionais das Supreme Audit Institutions e o nível de democracia dos países. Como hipótese de pesquisa entende-se que países com governos parlamentaristas possuem maior chance de apresentarem maiores índices de democracia do que países presidencialistas, e eles apresentam maior chance de possuírem SAIs auxiliando na consolidação da democracia. Para obtenção do resultado do problema foi realizada uma pesquisa qualitativa, do tipo documental, para identificar em qual modelo de SAI os países estavam inseridos e, posteriormente, por meio de uma análise quantitativa, realizada através das técnicas de medidas de efeitos, por meio da Odds Radio e da magnitude da associação, e teste qui-quadrado, que permitiram responder aos objetivos propostos. Os resultados apontam que a democracia possui associação com as três variáveis testadas: transparência, accountability e forma de governo. Estas são fundamentais para a consolidação da democracia, sendo a forma de governo aquela que maior exerce influência. No que diz respeito às Instituições de Auditoria, independentemente do modelo adotado, todos os testes apresentaram associação. Contudo, verificou-se que enquanto a transparência é mais associada ao modelo de Colegiado, as variáveis de accountability e forma de governo demonstraram em seus testes de associação que países optantes por modelos não Colegiados tendem a ser mais democráticos nesses quesitos, sendo a forma de governo a principal

A Model for the Propagation of Sound in Granular Materials

This paper presents a simple ball-and-spring model for the propagation of small amplitude vibrations in a granular material. In this model, the positional disorder in the sample is ignored and the particles are placed on the vertices of a square lattice. The inter-particle forces are modeled as linear springs, with the only disorder in the system coming from a random distribution of spring constants. Despite its apparent simplicity, this model is able to reproduce the complex frequency response seen in measurements of sound propagation in a granular system. In order to understand this behavior, the role of the resonance modes of the system is investigated. Finally, this simple model is generalized to include relaxation behavior in the force network -- a behavior which is also seen in real granular materials. This model gives quantitative agreement with experimental observations of relaxation.Comment: 21 pages, requires Harvard macros (9/91), 12 postscript figures not included, HLRZ preprint 6/93, (replacement has proper references included

Low Carbon Abundance in Type Ia Supernovae

We investigate the quantity and composition of unburned material in the outer layers of three normal Type Ia supernovae (SNe Ia): 2000dn, 2002cr and 20 04bw. Pristine matter from a white dwarf progenitor is expected to be a mixture of oxygen and carbon in approximately equal abundance. Using near-infrared (NIR, 0.7-2.5 microns) spectra, we find that oxygen is abundant while carbon is severely depleted with low upper limits in the outer third of the ejected mass. Strong features from the OI line at rest wavelength = 0.7773 microns are observed through a wide range of expansion velocities approx. 9,000 - 18,000 km/s. This large velocity domain corresponds to a physical region of the supernova with a large radial depth. We show that the ionization of C and O will be substantially the same in this region. CI lines in the NIR are expected to be 7-50 times stronger than those from OI but there is only marginal evidence of CI in the spectra and none of CII. We deduce that for these three normal SNe Ia, oxygen is more abundant than carbon by factors of 100 - 1,000. MgII is also detected in a velocity range similar to that of OI. The presence of O and Mg combined with the absence of C indicates that for these SNe Ia, nuclear burning has reached all but the extreme outer layers; any unburned material must have expansion velocities greater than 18,000 km/s. This result favors deflagration to detonation transition (DD) models over pure deflagration models for SNe Ia.Comment: accepted for publication in Ap