On the relation between the mass of Compact Massive Objects and their host galaxies

Supermassive black holes and/or very dense stellar clusters are found in the central regions of galaxies. Nuclear star clusters are present mainly in faint galaxies while upermassive black holes are common in galaxies with masses $\geq 10^{10}$ M$_\odot$. In the intermediate galactic mass range both types of central massive objects (CMOs) are found. Here we present our collection of a huge set of nuclear star cluster and massive black hole data that enlarges significantly already existing data bases useful to investigate for correlations of their absolute magnitudes, velocity dispersions and masses with structural parameters of their host galaxies. In particular, we directed our attention to some differences between the correlations of nuclear star clusters and massive black holes as subsets of CMOs with hosting galaxies. In this context, the mass-velocity dispersion relation plays a relevant role because it seems the one that shows a clearer difference between the supermassive black holes and nuclear star clusters. The $M_{MBH}-{\sigma}$ has a slope of $5.19\pm 0.28$ while $M_{NSC}-{\sigma}$ has the much smaller slope of $1.84\pm 0.64$. The slopes of the CMO mass- host galaxy B magnitude of the two types of CMOs are indistinguishable within the errors while that of the NSC mass-host galaxy mass relation is significantly smaller than for supermassive black holes. Another important result is the clear depauperation of the NSC population in bright galaxy hosts, which reflects also in a clear flattening of the NSC mass vs host galaxy mass at high host masses.Comment: 12 pages, 22 figures, 2 tables, accepted for publication in MNRA

Isolamento de bactérias associadas à palma e prospecção do potencial de solubilizar fosfato e fixar nitrogênio.

Bactérias associadas às cactáceas, adaptadas ao estresse hídrico e a altas temperaturas, podem ser usadas como inoculantes visando aumento de produtividade e recuperação de solos em processos de desertificação. Nesse sentido, visou-se selecionar bactérias endofíticas e rizobactérias de palma (Opuntia ficus-indica) quanto aos atributos de fixar N2 e solubilizar fosfato. Sessenta e nove linhagens de bactérias, isoladas em meio livre de nitrogênio (meio NFb) foram avaliadas quanto à presença dos genes nifH e nifD e à capacidade de solubilizar fosfato. Ficou evidenciado a presença do gene nifH em dez bactérias, sendo os gêneros identificados como Citrobacter, Sphingomonas, Ochrobactrum, Rodococcus, Stenotrophomonas e Enterobacter. Vinte dos isolados bacterianos avaliados foram capazes de solubilizar in vitro fosfato de rocha, sobressaindo-se o gênero Bacillus como hiperprodutor. As espécies B. megaterium e Enterobacter agglomerans apresentaram os maiores níveis de solubilização de fosfato. Estas bactérias, aliadas a outras características benéficas, podem ser usadas para inoculação de plântulas de cacto visando assegurar maior índice de desenvolvimento em solos com déficit hídrico

Topological phase transitions in ultra-cold Fermi superfluids: the evolution from BCS to BEC under artificial spin-orbit fields

We discuss topological phase transitions in ultra-cold Fermi superfluids induced by interactions and artificial spin orbit fields. We construct the phase diagram for population imbalanced systems at zero and finite temperatures, and analyze spectroscopic and thermodynamic properties to characterize various phase transitions. For balanced systems, the evolution from BCS to BEC superfluids in the presence of spin-orbit effects is only a crossover as the system remains fully gapped, even though a triplet component of the order parameter emerges. However, for imbalanced populations, spin-orbit fields induce a triplet component in the order parameter that produces nodes in the quasiparticle excitation spectrum leading to bulk topological phase transitions of the Lifshitz type. Additionally a fully gapped phase exists, where a crossover from indirect to direct gap occurs, but a topological transition to a gapped phase possessing Majorana fermions edge states does not occur.Comment: With no change in text, the labels in the figures are modifie

Microwave-assisted generation and reactivity of aza- and diazafulvenium methides: heterocycles via pericyclic reactions

Azafulvenium methides and diazafulvenium methides have been generated under microwave irradiation from 2,2-dioxo-1H,3H-pyrrolo[1,2-c]thiazoles and 2,2-dioxo-1H,3H-pyrazolo[1,5-c]thiazoles, respectively. Pericyclic reactions of these 1,7-dipole intermediates, namely, sigmatropic [1,8]H shifts, 1,7-electrocyclization or [8[pi]+2[pi]] cycloaddition led to the synthesis of a range of pyrrole and pyrazole derivatives. The first evidence for the azafulvenium methides by intermolecular trapping via [8[pi]+2[pi]] cycloaddition is reported.http://www.sciencedirect.com/science/article/B6THS-4SP3SM3-6/1/d6303d9db78919cfe9cd796c1a17d44