Magnetically Driven Outflows in a Starburst Environment

We here investigate the possibility that the observed collimated outflows in luminous infrared galaxies (LIGs) and some Seyfert galaxies can be produced in a starburst (SB) environment. A nuclear disk can be quickly produced by gas infall during star formation in a rotating, stellar cluster. We find that massive nuclear SBs with core disk masses M_d \sim 10^8 - 10^9 M_{\odot}, and supernova rates \nu_{SN} \simeq 5 \times 10^{-3} - 2 yr^{-1} (which are consistent with the \nu_{SN} values inferred from the observed non-thermal radio power in source candidates) may inject kinetic energies which are high enough to blow out directed flows from the accreting disk surface, within the SB lifetimes. In our models, the acceleration and collimation of the nuclear outflow are provided by magnetic fields anchored into the rotating SB-disk. The emerging outflow carries a kinetic power that is only a small fraction (a few percent) of the supernovae energy rate produced in the SB. Based on conditions determined from observed outflows and disks, we find that moderate disk magnetic fields (\gtrsim 8 \times 10^{-4} G) are able to accelerate the outflows up to the observed terminal velocities (\lesssim few 100 km s^{-1} in the case of the Seyfert galaxies, and \sim 400 - 950 km s^{-1} in the case of the LIGs). The outflow is produced within a wind zone in the disk of radius \lesssim 100 pc in the LIGs, and \lesssim 10 pc in the Seyferts, with wind mass loss to disk accretion rate ratios \dot M_w /\dot M_d \gtrsim 0.1 (where \dot M_d \sim 100 M_{\odot} yr^{-1}). The observation of rotating nuclear disks of gas within few 100 pc scales in source candidates like the LIG Arp 220, and magnetized outflows provide observational support for the picture drawn here.Comment: 31 pages, Latex file, 1 Figure, accepted for publication in the Astrophys. Journa

Specific configuration of dendritic degeneration in pyramidal neurons of the medial prefrontal cortex induced by differing corticosteroid regimens

We previously demonstrated that hypercorticalism induces pronounced volumetric reductions in the rat medial prefrontal cortex (mPFC) and that these structural changes correlate with deficits in executive function. By applying 3-dimensional analysis of Golgi- Cox--stained material, we now demonstrate that corticosteroids can exert differential effects on dendritic arborizations of pyramidal neurons in lamina II/III of the mPFC. Treatment with the glucocorticoid receptor--selective agonist dexamethasone and with the natural adrenosteroid, corticosterone (CORT), results in significant reductions in the total length of apical dendrites in the pyramidal neurons in lamina II/III of the anterior cingulate/prelimbic and infralimbic cortices. Interestingly, although these treatments do not affect the number of dendritic branches, they are associated with impoverished arborizations in their distal portions and, in CORTtreated animals, with increased branching in the middle portions of the apical dendritic tree. Deprivation of corticosteroids by adrenalectomy leads to decreases in total apical dendritic length and spine number, but in this case, dendritic impoverishment was restricted to the middle/proximal segments of the dendritic trees. None of the treatments influenced the architecture of the basal dendrites. These results add to our knowledge of the morphological substrates through which corticosteroids may disrupt mPFC-dependent behaviors

A NOTE ON TRANSIENT HEAT TRANSFER PROBLEMS WITH TEMPERATURE-DEPENDENT THERMAL CONDUCTIVITY AND THERMAL DIFFUSIVITY

In this work it is presented a numerical procedure for solving transient heat transfer problems in which the thermal diffusivity is strongly dependent on the temperature, with the aid of the Kirchhoff transformation associated to an usual finite difference approach. The first step consists of eliminating the nonlinear terms associated to the derivatives with respect to the position, by means of a Kirchhoff transformation, giving rise to a partial differential equation with only one nonlinear term (involving the coefficient of the derivative with respect to the time). The advance in time is carried out assuming the thermal diffusivity evaluated at a known temperature, giving rise to a semi-implicit scheme. Comparisons between this approach and the usual hypothesis are carried out in order to illustrate the effect of the dependence between the temperature and the thermal diffusivity. Some typical results are presented, based on the (6H-SiC) Silicon Carbide properties

Influencia de la densidad animal en la respuesta productiva de conejos en una explotación industrial

publishedTomo I . Sección: Sistemas Ganaderos-Economía y Gestión. Sesión: Conejos, abejas, peces y cerdos. Ponencia nº 2

Caracterização de híbridos ornamentais de bananeira.

As fruteiras ornamentais são uma alternativa para o segmento da floricultura, possuem grande plasticidade de uso podendo ser apreciadas como plantas de parques, jardins, flores de corte, plantas de vaso, folhagens e minifrutos ornamentais. O Banco de Germoplasma de Bananeira da Embrapa Mandioca e Fruticultura possui acessos de diferentes seções do gênero Musa.PDF. 120_11

Demanda de informação em sistemas agroflorestais para agricultura familiar sustentável no Nordeste paraense.

Práticas alternativas começam a ser vistas como uma garantia de preservação dos sistemas produtivos da agricultura familiar. O uso de sistemas alternativos para recuperação de áreas degradadas e/ou abandonadas é fundamental para alcançar sustentabilidade de unidades de produção familiar rurais, com propostas tecnológicas e baseadas no conhecimento e uso racional dos recursos naturais. Disponibilizar alternativas sustentáveis à recuperação de áreas degradadas com agricultura e pastagens com vistas ao uso sustentado da terra e melhoria de vida dos agricultores da Amazônia foi objetivo do projeto "Desenvolvimento e Validação de Estratégias Participativas de Recuperação de Áreas Agrícolas e Pastagens Degradadas na Amazônia", componente da Sub-Rede RECUPERAMAZ. Para viabilizar o processo de divulgação científica dos resultados de pesquisa, foi realizada uma ação de identificação de demanda por informação, aplicando-se metodologia apropriada e adaptada, para 81 agricultores familiares, representantes de 16 associações comunitárias rurais, distribuídos entre os municípios de Igarapé-Açu, Mãe do Rio e Concórdia do Pará, região Nordeste Paraense. Os resultados indicam que os agricultores apresentam um perfil que facilita o processo de divulgação dos resultados de pesquisas, com maior ou menor habilidade para uso de diferentes mídias e fontes. Demonstram interesse em "novos" conhecimentos, i.e. através das informações fornecidas por técnicos, pelas instituições governamentais e não-governamentais entre outros e demandam informações relacionadas às suas práticas agrícolas cotidianas para soluções de diferentes problemas

Seleção de híbridos de bananeira com potencial para minifrutos ornamentais e paisagismo.

O mercado de plantas ornamentais está sempre em busca de novos produtos. A bananeira é uma fruteira tropical de porte médio a alto, com folhagem verde exuberante e frutos geralmente de coloração verde a amarela. A geração de plantas de pequeno porte com coloração de frutos e inflorescência masculina variados, que possam ser cultivadas em espaços reduzidos, assim como a opção de se utilizar frutos pequenos em arranjos ornamentais é um diferencial interessante para o mercado de floricultura tropical.PDF.69

Wafer scale fabrication of graphene microelectrode arrays for the detection of DNA hybridization

Since the discovery of graphene, and due to its unique properties, we have witnessed a growing interest in the use of graphene-based devices for applications in the most diverse areas, namely in biosensing, particularly in the detection of genetic material. DNA can bind directly to graphene without the need of a linker and that makes this platform highly interesting for biosensor development. Here, electrochemical chips consisting of 6 independent gold microelectrode arrays as working electrode, and platinum reference and counter electrodes were fabricated at the wafer scale and, after graphene transfer and patterning, were used in the detection of DNA hybridization. Combining the sensitivity of electrochemical impedance spectroscopy and the selectivity of DNA beacons, we were able to detect DNA hybridization in a linear range between 5 pM and 5 nM, which is in the relevant clinical range for many diseases, with sensitivity to single nucleotide polymorphism.Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013info:eu-repo/semantics/acceptedVersio