A situaçao da conservaçao do solo e da agua no Brasil : o papel do SNLCS da EMBRAPA

Ce rapport fait le point de la situation de la recherche et des connaissances de gestion et de conservation des sols et des eaux au Brésil. Un inventaire des différentes institutions et organismes qui travaillent dans ces domaines ou en financent les recherches est dressé et le bilan des résultats déjà acquis dans les cinq grandes régions du pays établi. Un diagnostic des points faibles et des secteurs carentiels par région est tenté et de nouvelles lignes de recherche sont préconisées. En conclusion des solution possibles sont présentées au niveau national et à celui particulier du SNLCS de l'EMBRAPA. (Résumé d'auteur

The dynamics of z = 0.8 Hα-selected star-forming galaxies from KMOS/CF-HiZELS

We present the spatially resolved Hα dynamics of 16 star-forming galaxies at z ~ 0.81 using the new KMOS multi-object integral field spectrograph on the ESO Very Large Telescope. These galaxies, selected using 1.18 μm narrowband imaging from the 10 deg2 CFHT-HiZELS survey of the SA 22 hr field, are found in a ~4 Mpc overdensity of Hα emitters and likely reside in a group/intermediate environment, but not a cluster. We confirm and identify a rich group of star-forming galaxies at z = 0.813 ± 0.003, with 13 galaxies within 1000 km s–1 of each other, and seven within a diameter of 3 Mpc. All of our galaxies are "typical" star-forming galaxies at their redshift, 0.8 ± 0.4 SFR$^*_{z = 0.8}$, spanning a range of specific star formation rates (sSFRs) of 0.2-1.1 Gyr–1 and have a median metallicity very close to solar of 12 + log(O/H) = 8.62 ± 0.06. We measure the spatially resolved Hα dynamics of the galaxies in our sample and show that 13 out of 16 galaxies can be described by rotating disks and use the data to derive inclination corrected rotation speeds of 50-275 km s–1. The fraction of disks within our sample is 75% ± 8%, consistent with previous results based on Hubble Space Telescope morphologies of Hα-selected galaxies at z ~ 1 and confirming that disks dominate the SFR density at z ~ 1. Our Hα galaxies are well fitted by the z ~ 1-2 Tully-Fisher (TF) relation, confirming the evolution seen in the zero point. Apart from having, on average, higher stellar masses and lower sSFRs, our group galaxies at z = 0.81 present the same mass-metallicity and TF relation as z ~ 1 field galaxies and are all disk galaxies

A relationship between specific star formation rate and metallicity gradient within z ∼ 1 galaxies from KMOS-HiZELS

We have observed a sample of typical z ∼ 1 star-forming galaxies, selected from the HiZELS survey, with the new K-band Multi-Object Spectrograph (KMOS) near-infrared, multi-integral field unit instrument on the Very Large Telescope (VLT), in order to obtain their dynamics and metallicity gradients. The majority of our galaxies have a metallicity gradient consistent with being flat or negative (i.e. higher metallicity cores than outskirts). Intriguingly, we find a trend between metallicity gradient and specific star formation rate (sSFR), such that galaxies with a high sSFR tend to have relatively metal poor centres, a result which is strengthened when combined with data sets from the literature. This result appears to explain the discrepancies reported between different high-redshift studies and varying claims for evolution. From a galaxy evolution perspective, the trend we see would mean that a galaxy's sSFR is governed by the amount of metal-poor gas that can be funnelled into its core, triggered either by merging or through efficient accretion. In fact, merging may play a significant role as it is the starburst galaxies at all epochs, which have the more positive metallicity gradients. Our results may help to explain the origin of the fundamental metallicity relation, in which galaxies at a fixed mass are observed to have lower metallicities at higher star formation rates, especially if the metallicity is measured in an aperture encompassing only the central regions of the galaxy. Finally, we note that this study demonstrates the power of KMOS as an efficient instrument for large-scale resolved galaxy surveys

The KMOS Deep Survey (KDS) – I. Dynamical measurements of typical star-forming galaxies at z ≃ 3.5

We present dynamical measurements from the KMOS (K-band Multi-Object Spectrograph) Deep Survey (KDS), which is comprised of 77 typical star-forming galaxies at z z ≃ 3.5 in the mass range 9.0 1), with the sample average VC/σint value much smaller than at lower redshift. After carefully selecting comparable star-forming samples at multiple epochs, we find that the rotation-dominated fraction evolves with redshift with a z−0.2 dependence. The rotation-dominated KDS galaxies show no clear offset from the local rotation velocity-stellar mass (i.e. VC − M⋆) relation, although a smaller fraction of the galaxies are on the relation due to the increase in the dispersion-dominated fraction. These observations are consistent with a simple equilibrium model picture, in which random motions are boosted in high-redshift galaxies by a combination of the increasing gas fractions, accretion efficiency, specific star-formation rate and stellar feedback and which may provide significant pressure support against gravity on the galactic disk scale

Risk-factors for non-adherence to antiretroviral therapy

Cross-sectional study analyzed as case-control to identify risk factors for non-adherence to antiretroviral therapy. We studied 412 out-clinics HIV infected subjects of three public hospitals of Recife, Pernambuco. The objective was to examine the association between non-adherence to the antiretroviral therapy and biological, social-behavior and demographics and economic factors, factors related to the disease and/or treatment, factors related to life habits and depression symptoms. Variables significantly associated with non-adherence to antiretroviral therapy were: time elapsed since HIV diagnosis (p = 0.002), daily dose (p = 0.046), use of alcohol (p = 0.030) and past drug use (p = 0.048), and borderline p-values were found for educational level (p = 0.093) and family monthly income (p = 0.08). In the multivariable analysis, the factors that remained in the final model were family monthly income, time period with HIV infection and use of alcohol. No association was observed between non-adherence to antiretroviral therapy and gender, age, sexual orientation, marital status, educational level and place of residence. Based on our results and the local situation we suggest: assessment of social needs; training of partners and/or families on supporting adherence, creation of "adherence groups" to motivate and to reassure patients on the benefits of treatment; counseling and/or psychotherapy for alcohol drinkers