Dominant Strategy Mechanisms with Multidimensional Types

This paper provides a characterization of dominant strategy mechanisms with quasi-linear utilities and multi-dimensional types for a variety of preference domains. These characterizations are in terms of a monotonicity property on the underlying allocation rule.Dominant Strategy, Farkas Lemma, Combinatorial Auctions.

Role of macrophage migration inhibitory factor (MIF) in allergic and endotoxin-induced airway inflammation in mice.

Macrophage migration inhibitory factor (MIF) has recently been forwarded as a critical regulator of inflammatory conditions, and it has been hypothesized that MIF may have a role in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). Hence, we examined effects of MIF immunoneutralization on the development of allergen-induced eosinophilic inflammation as well as on lipopolysaccharide (LPS)-induced neutrophilic inflammation in lungs of mice. Anti-MIF serum validated with respect to MIF neutralizing capacity or normal rabbit serum (NRS) was administered i.p. repeatedly during allergen aerosol exposure of ovalbumin (OVA)-immunized mice in an established model of allergic asthma, or once before instillation of a minimal dose of LPS into the airways of mice, a tentative model of COPD. Anti-MIF treatment did not affect the induced lung tissue eosinophilia or the cellular composition of bronchoalveolar lavage fluid (BALF) in the asthma model. Likewise, anti-MIF treatment did not affect the LPS-induced neutrophilia in lung tissue, BALF, or blood, nor did it reduce BALF levels of tumor necrosis factor-alpha (TNF-alpha) and macrophage inflammatory protein-1alpha (MIP-1alpha). The present data suggest that MIF is not critically important for allergen-induced eosinophilic, and LPS-induced neutrophilic responses in lungs of mice. These findings do not support a role of MIF inhibition in the treatment of inflammatory respiratory diseases

Relações de poder e participação dos agricultores familiares na gestão das águas na Bacia do Itajaí (SC, Brasil).

Este trabalho trata da participação dos agricultores familiares, em sua diversidade sócio-econômica, na gestão das águas na Bacia do Itajaí/SC, especialmente a partir dos pressupostos da Lei Federal 9.433/97, que instituiu a Nova Política Nacional de Recursos Hídricos. Analisamos os alcances e os limites do sistema de participação preconizado pela referida Lei a respeito das possibilidades de decisão dos agricultores familiares nas diferentes etapas da gestão das águas (elaboração, decisão e execução das propostas), no âmbito da Bacia do Itajaí, sobretudo, a partir de alguns dos últimos trabalhos de Michel Foucault (Último Foucault). Esta perspectiva teórica permitiu visualizar como as suas possibilidades de ação são delimitadas a partir de sua constituição como sujeitos livres e ativos em relações de poder pautadas no saber técnico-científico. A partir dessas relações, os agricultores familiares passam a se conceber como “usuários” ou “não usuários da água” e a assumir que sua função é executar tarefas propostas por quem detém conhecimento técnicocientífico. Consideramos que este fato pode ter sérias implicações quanto à reprodução social desses grupos, porque exclui do processo de gestão das águas a discussão de seu modo específico de utilização da terra e de suas características sócio-culturais. Além disso, descarta determinadas possibilidades de recuperação ambiental que poderiam ser construídas com o auxílio do saber dos agricultores

Triply deuterated ammonia in NGC 1333

The Caltech Submillimeter Observatory has detected triply deuterated ammonia, ND3, through its 10a-00s transition near 310 GHz. Emission is found in the NGC 1333 region, both towards IRAS 4A and a position to the South-East where DCO+ peaks. In both cases, the hyperfine ratio indicates that the emission is optically thin. Column densities of ND3 are 3--6 x 10^11 cm^-2 for T_ex=10 K and twice as high for T_ex=5 K. Using a Monte Carlo radiative transfer code and a model of the structure of the IRAS source with temperature and density gradients, the estimated ND3 abundance is 3.2 x 10^-12 if ND3/H2 is constant throughout the envelope. In the more likely case that ND3/H2D+ is constant, ND3/H2 peaks in the cold outer parts of the source at a value of 1.0 x 10^-11. To reproduce the observed NH3/ND3 abundance ratio of ~1000, grain surface chemistry requires an atomic D/H ratio of ~0.15 in the gas phase, >10 times higher than in recent chemical models. More likely, the deuteration of NH3 occurs by ion-molecule reactions in the gas phase, in which case the data indicate that deuteron transfer reactions are much faster than proton transfers.Comment: 4 pages, 2 figures; to be published in Astronomy & Astrophysics (Letters

Loss of genetic diversity and increased embryonic mortality in non-native lizard populations

Many populations are small and isolated with limited genetic variation and high risk of mating with close relatives. Inbreeding depression is suspected to contribute to extinction of wild populations, but the historical and demographic factors that contribute to reduced population viability are often difficult to tease apart. Replicated introduction events in non-native species can offer insights into this problem because they allow us to study how genetic variation and inbreeding depression are affected by demographic events (e.g. bottlenecks), genetic admixture and the extent and duration of isolation. Using detailed knowledge about the introduction history of 21 nonnative populations of the wall lizard Podarcis muralis in England, we show greater loss of genetic diversity (estimated from microsatellite loci) in older populations and in populations from native regions of high diversity. Loss of genetic diversity was accompanied by higher embryonic mortality in non-native populations, suggesting that introduced populations are sufficiently inbred to jeopardize long-term viability. However, there was no statistical correlation between population-level genetic diversity and average embryonic mortality. Similarly, at the individual level, there was no correlation between female heterozygosity and clutch size, infertility or hatching success, or between embryo heterozygosity and mortality. We discuss these results in the context of human-mediated introductions and how the history of introductions can play a fundamental role in influencing individual and population fitness in non-native species