Relativistic O(q4)O(q^4) two-pion exchange nucleon-nucleon potential: configuration space

We have recently performed a relativistic $O(q^4)$ chiral expansion of the two-pion exchange $NN$ potential, and here we explore its configuration space content. Interactions are determined by three families of diagrams, two of which involve just $g_A$ and $f_{\pi}$, whereas the third one depends on empirical coefficients fixed by subthreshold $\pi N$ data. In this sense, the calculation has no adjusted parameters and gives rise to predictions, which are tested against phenomenological potentials. The dynamical structure of the eight leading non-relativistic components of the interaction is investigated and, in most cases, found to be clearly dominated by a well defined class of diagrams. In particular, the central isovector and spin-orbit, spin-spin, and tensor isoscalar terms are almost completely fixed by just $g_A$ and $f_{\pi}$. The convergence of the chiral series in powers of the ratio (pion mass/nucleon mass) is studied as a function of the internucleon distance and, for $r>$ 1 fm, found to be adequate for most components of the potential. An important exception is the dominant central isoscalar term, where the convergence is evident only for $r>$ 2.5 fm. Finally, we compare the spatial behavior of the functions that enter the relativistic and heavy baryon formulations of the interaction and find that, in the region of physical interest, they differ by about 5%.Comment: 27 pages, 33 figure

Efeito do aquecimento global sobre a comunidade microbiana do solo.

A relação entre as comunidades microbianas do solo e o aquecimento global pode ser vista de duas formas. Na primeira, os microrganismos contribuem para a emissão de gases de efeito estufa, sendo os principais atores nos processos de ciclagem de nutrientes e de fluxos globais de CO2, CH4 e N2. Na segunda, é importante entender como o aquecimento global, resultado das mudanças climáticas, afeta a comunidade microbiana do solo. Considerando que a elevação do CO2, temperatura e precipitação são fatores importantes que influenciam as comunidades do solo, neste capítulo serão discutidos seus efeitos na comunidade microbiana do solo de forma geral e nos patógenos existentes nos solos no contexto do aquecimento global

Entropic Entanglement Criteria for Continuous Variables

We derive several entanglement criteria for bipartite continuous variable quantum systems based on the Shannon entropy. These criteria are more sensitive than those involving only second-order moments, and are equivalent to well-known variance product tests in the case of Gaussian states. Furthermore, they involve only a pair of quadrature measurements, and will thus should prove extremely useful the experimental identification of entanglement.Comment: 4 pages, 2 figure

Effects from inhomogeneities in the chiral transition

We consider an approximation procedure to evaluate the finite-temperature one-loop fermionic density in the presence of a chiral background field which systematically incorporates effects from inhomogeneities in the chiral field through a derivative expansion. We apply the method to the case of a simple low-energy effective chiral model which is commonly used in the study of the chiral phase transition, the linear sigma-model coupled to quarks. The modifications in the effective potential and their consequences for the bubble nucleation process are discussed.Comment: 11 pages, 5 figures. v2: appendix and references added, published versio

Rhizosphere microbial community manipulation under salted soil by the inoculation of Pseudomonas sp CMAA 1215 in Zea mays.

Soil salinity reduces the soil organic carbon stock, the microbial biomass and activity and modifies the biogeochemical cycle and the microbial diversity. Osmotic stress caused by ethylene on plants can be reduced using 1-aminocyclopropane-1-carboxylate (ACC) deaminase plant growth promoting bacteria (PGPR) producers. Studies of PGPR and commercially strains are based only on the growth of the plant without concern about modification of the microbial community. This scenario has shown an increasing need to study the ecological functions of bacterial community on salted soil and to develop new technologies to reduce environmental impacts and waste of natural resources. Our aim was to study the influence of the Pseudomonas sp. CMAA1215, a known ACC deaminase on rhizosphere bacteria community of Zea mays under saline soil by sequencing the rhizosphere metagenome. The NMDS of the OTU table (ANOSIM p<0.01) discriminate all the treatments (with and without inoculation under salted and non-salted soils) indicating a modification of the bacteria community by inoculation or by soil salinization. The main groups of the rhizosphere that had the abundance increased by Pseudomonas inoculation were Acidobacteriales, Solibacteriales, Bacillales and Rhizobiales. The relative abundance of Rhodospirillales (Alphaproteobacteria) and Chthoniobacterales (Spartobacteria) was stimulated by the inoculation only under higher salinization. The inoculation can be important to stimulate other PGPR under saline soil or microbes that are not benefic to plants

Genome sequence of Streptomyces caatingaensis CMAA 1322, a new abiotic stress-tolerant actinomycete isolated from dried lake bed sediment in the Brazilian Caatinga Biome.

The genome sequence of the first Streptomyces species isolated from the Brazilian Caatinga is reported here. Genes related to environmental stress tolerance were prevalent and included many secondary metabolic gene clusters