A produçao familiar como alternativa de um desenvolvimento sustentável para a Amazônia; Liçoes aprendidas de iniciativas de uso florestal por produtores familiares na Amazônia boliviana, brasileira, equatoriana e peruana

Abstract: Between 2005 and 2009, the EU-financed project ForLive set out to analyse promising local forest management initiatives in the Amazon Basin in four countries: Ecuador, Bolivia, Brazil, and Peru. Researchers aimed to identify locally viable practices that benefit livelihoods and ecological stabilisation of landscapes, as well as to define ways to promote these practices as a basis for sound rural development. This book presents lessons learnt from more than 100 studies by researchersfrom Latin America, from practitioners and from local families themselves. The findings suggest that the focus of current development strategies designed to support smallholders in adopting management and organization, which are usually externally defined systems made from expert-driven policy and research, mayrequire a review of fundamental assumptions and methods. Most of these initiatives widely ignored the immense potential of Amazonian smallholders—settlers, traditional communities and indigenous groups—to contribute to sound rural development with their own ideas and knowledge. Strong evidence was found that the socio-productive systems of Amazonian smallholders could serve as a reference for new methods that support a more equitable and environmentallysustainable development of the region

Power-law spin correlations in pyrochlore antiferromagnets

The ground state ensemble of the highly frustrated pyrochlore-lattice antiferromagnet can be mapped to a coarse-grained ``polarization'' field satisfying a zero-divergence condition From this it follows that the correlations of this field, as well as the actual spin correlations, decay with separation like a dipole-dipole interaction ($1/|R|^3$). Furthermore, a lattice version of the derivation gives an approximate formula for spin correlations, with several features that agree well with simulations and neutron-diffraction measurements of diffuse scattering, in particular the pinch-point (pseudo-dipolar) singularities at reciprocal lattice vectors. This system is compared to others in which constraints also imply diffraction singularities, and other possible applications of the coarse-grained polarization are discussed.Comment: 13 pp, revtex, two figure

The nsp1, nsp13, and M Proteins Contribute to the Hepatotropism of Murine Coronavirus JHM.WU

ABSTRACT Mouse hepatitis virus (MHV) isolates JHM.WU and JHM.SD promote severe central nervous system disease. However, while JHM.WU replicates robustly and induces hepatitis, JHM.SD fails to replicate or induce pathology in the liver. These two JHM variants encode homologous proteins with few polymorphisms, and little is known about which viral proteins(s) is responsible for the liver tropism of JHM.WU. We constructed reverse genetic systems for JHM.SD and JHM.WU and, utilizing these full-length cDNA clones, constructed chimeric viruses and mapped the virulence factors involved in liver tropism. Exchanging the spike proteins of the two viruses neither increased replication of JHM.SD in the liver nor attenuated JHM.WU. By further mapping, we found that polymorphisms in JHM.WU structural protein M and nonstructural replicase proteins nsp1 and nsp13 are essential for liver pathogenesis. M protein and nsp13, the helicase, of JHM.WU are required for efficient replication in vitro and in the liver in vivo . The JHM.SD nsp1 protein contains a K194R substitution of Lys194, a residue conserved among all other MHV strains. The K194R polymorphism has no effect on in vitro replication but influences hepatotropism, and introduction of R194K into JHM.SD promotes replication in the liver. Conversely, a K194R substitution in nsp1 of JHM.WU or A59, another hepatotropic strain, significantly attenuates replication of each strain in the liver and increases IFN-β expression in macrophages in culture. Our data indicate that both structural and nonstructural proteins contribute to MHV liver pathogenesis and support previous reports that nsp1 is a Betacoronavirus virulence factor. IMPORTANCE The Betacoronavirus genus includes human pathogens, some of which cause severe respiratory disease. The spread of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) into human populations demonstrates the zoonotic potential of emerging coronaviruses, and there are currently no vaccines or effective antivirals for human coronaviruses. Thus, it is important to understand the virus-host interaction that regulates coronavirus pathogenesis. Murine coronavirus infection of mice provides a useful model for the study of coronavirus-host interactions, including the determinants of tropism and virulence. We found that very small changes in coronavirus proteins can profoundly affect tropism and virulence. Furthermore, the hepatotropism of MHV-JHM depends not on the spike protein and viral entry but rather on a combination of the structural protein M and nonstructural replicase-associated proteins nsp1 and nsp13, which are conserved among betacoronaviruses. Understanding virulence determinants will aid in the design of vaccines and antiviral strategies

Electron correlations for ground state properties of group IV semiconductors

Valence energies for crystalline C, Si, Ge, and Sn with diamond structure have been determined using an ab-initio approach based on information from cluster calculations. Correlation contributions, in particular, have been evaluated in the coupled electron pair approximation (CEPA), by means of increments obtained for localized bond orbitals and for pairs and triples of such bonds. Combining these results with corresponding Hartree-Fock (HF) data, we recover about 95 % of the experimental cohesive energies. Lattice constants are overestimated at the HF level by about 1.5 %; correlation effects reduce these deviations to values which are within the error bounds of this method. A similar behavior is found for the bulk modulus: the HF values which are significantly too high are reduced by correlation effects to about 97 % of the experimental values.Comment: 22 pages, latex, 2 figure

Effect of photon flux densities on regulation of carotenogenesis and cell viability of Haematococcus pluvialis (Chlorophyceae)

The green alga Haematococcus pluvialis produces large amounts of the pink carotenoid astaxanthin under high photon flux density (PFD) and other oxidative stress conditions. However, the regulation and physiological role of carotenogenesis leading to astaxanthin formation is not well understood. Comparative transcriptional expression of five carotenoid genes along with growth and pigment composition as a function of PFD was studied using a wild-type and an astaxanthin-overproduction mutant of H. pluvialis NIES144. The results indicate that astaxanthin biosynthesis was mainly under transcriptional control of the gene encoding carotenoid hydroxylase, and to a lesser extent, the genes encoding isopentenyl isomerase and phytoene desaturase, and to the least extent, the genes encoding phytoene synthase and carotenoid oxygenase. The expression of a plastid terminal oxidase (PTOX) gene ptox2 underwent transient up-regulation under elevated PFDs, suggesting that PTOX may be functionally coupled with phytoene desaturase through the plastoquinone pool and may play a role in reducing redox-potential-dependent and oxygen-concentration-dependent formation of reactive oxygen species in the chloroplast. Over-expression of both the carotenogenic and PTOX genes confers to the astaxanthin-overproduction mutant more effective photoprotective capability than that of the wild type under photooxidative stress

Abordagem Gespan.

O contexto da abordagem GESPAN. Abordagem GESPAN - projeto piloto. Produtos estratégicos gerados pela abordagem GESPAN. Abordagem GESPAN: desafios futuros.bitstream/item/63645/1/Oriental-Doc221.PD

Viking Afterbody Heating Computations and Comparisons to Flight Data

Computational fluid dynamics predictions of Viking Lander 1 entry vehicle afterbody heating are compared to flight data. The analysis includes a derivation of heat flux from temperature data at two base cover locations, as well as a discussion of available reconstructed entry trajectories. Based on the raw temperature-time history data, convective heat flux is derived to be 0.63-1.10 W/sq cm for the aluminum base cover at the time of thermocouple failure. Peak heat flux at the fiberglass base cover thermocouple is estimated to be 0.54-0.76 W/sq cm, occurring 16 seconds after peak stagnation point heat flux. Navier-Stokes computational solutions are obtained with two separate codes using an 8-species Mars gas model in chemical and thermal non-equilibrium. Flowfield solutions using local time-stepping did not result in converged heating at either thermocouple location. A global time-stepping approach improved the computational stability, but steady state heat flux was not reached for either base cover location. Both thermocouple locations lie within a separated flow region of the base cover that is likely unsteady. Heat flux computations averaged over the solution history are generally below the flight data and do not vary smoothly over time for both base cover locations. Possible reasons for the mismatch between flight data and flowfield solutions include underestimated conduction effects and limitations of the computational methods

Genetic studies of paired metabolomes reveal enzymatic and transport processes at the interface of plasma and urine.

The kidneys operate at the interface of plasma and urine by clearing molecular waste products while retaining valuable solutes. Genetic studies of paired plasma and urine metabolomes may identify underlying processes. We conducted genome-wide studies of 1,916 plasma and urine metabolites and detected 1,299 significant associations. Associations with 40% of implicated metabolites would have been missed by studying plasma alone. We detected urine-specific findings that provide information about metabolite reabsorption in the kidney, such as aquaporin (AQP)-7-mediated glycerol transport, and different metabolomic footprints of kidney-expressed proteins in plasma and urine that are consistent with their localization and function, including the transporters NaDC3 (SLC13A3) and ASBT (SLC10A2). Shared genetic determinants of 7,073 metabolite-disease combinations represent a resource to better understand metabolic diseases and revealed connections of dipeptidase 1 with circulating digestive enzymes and with hypertension. Extending genetic studies of the metabolome beyond plasma yields unique insights into processes at the interface of body compartments

Polymorphic residues in rice NLRs expand binding and response to effectors of the blast pathogen

Accelerated adaptive evolution is a hallmark of plant-pathogen interactions. Plant intracellular immune receptors (NLRs) often occur as allelic series with differential pathogen specificities. The determinants of this specificity remain largely unknown. Here, we unravelled the biophysical and structural basis of expanded specificity in the allelic rice NLR Pik, which responds to the effector AVR-Pik from the rice blast pathogen Magnaporthe oryzae. Rice plants expressing the Pikm allele resist infection by blast strains expressing any of three AVR-Pik effector variants, whereas those expressing Pikp only respond to one. Unlike Pikp, the integrated heavy metal-associated (HMA) domain of Pikm binds with high affinity to each of the three recognized effector variants, and variation at binding interfaces between effectors and Pikp-HMA or Pikm-HMA domains encodes specificity. By understanding how co-evolution has shaped the response profile of an allelic NLR, we highlight how natural selection drove the emergence of new receptor specificities. This work has implications for the engineering of NLRs with improved utility in agriculture