614 research outputs found
Evaluation of initial growth of poplar clones in North Patagonia
En los valles irrigados de Río Negro y
Neuquén, el cultivo de álamos acompañó
históricamente la producción agrícola,
utilizándose clones de Populus nigra L. en cortinas
rompeviento y clones de Populus xcanadensis
Moench. para las forestaciones en macizo.
Buscando ampliar la disponibilidad de genotipos
para los diferentes sitios de cultivo, se instaló
un ensayo comparativo con trece clones de
álamo en la localidad de Pomona, Provincia
de Río Negro. Se evaluaron seis clones de
P. xcanadensis ('Triplo', 'Ragonese 22 INTA',
"Pangui INTA", "Pudú INTA", y los testigos
comerciales 'Conti 12' e 'I-214'), seis clones de
P. deltoides ('Harvard', 'Onda', 'Stoneville 67',
'Carabelas INTA', "20-82" y "C-657") y un clon de
P. xcanescens. Se utilizó un diseño experimental
de bloques completos al azar (DBCA) con quince
repeticiones y parcelas de una planta. Luego
de cuatro períodos de crecimiento, 'I-214' y
'Triplo' tuvieron los mayores incrementos de
DAP, no encontrándose diferencias significativas
con los valores de 'Conti 12', 'Ragonese
22 INTA', "Pangui INTA", "Pudú INTA", "20-82" y
P. xcanescens. Los menores crecimientos fueron
observados en los deltoides 'Stoneville 67' y
"C- 657". Los clones 'Ragonese 22 INTA', 'Triplo'
y "20-82" constituyen alternativas para el cultivo
de álamos en macizos y cortinas rompeviento.In the irrigated valleys of Río Negro
and Neuquén poplar cultivation historically
accompanied agricultural production using
clones of Populus nigra L. in shelterbelts
and Populus xcanadensis Moench. in forest
plantations. With the aim to extend the availability
of genotypes for different cultivation sites,
a comparative trial with thirteen clones of
poplar was installed at Pomona, Río Negro
province. Six clones of euramerican hybrid
poplar (P. xcanadensis 'Triplo', 'Ragonese
22 INTA', "Pangui INTA", "Pudú INTA" and
commercial control 'Conti 12' and 'I-214'),
six clones of eastern cottonwood poplar
(P. deltoides 'Harvard', 'Onda', 'Stoneville 67',
'Carabelas INTA', "20-82" and "C-657") and
one clone of P. xcanescens were evaluated. A
completely randomized block design was used
with fifteen replications and one plant per plot.
After four growth periods, 'I-214' and 'Triplo'
had the largest increases of diameter at breast
height (DBH) while no significant differences in
the values of 'Conti 12', 'Ragonese 22 INTA',
"Pangui INTA", "Pudú INTA", "20-82" and
P. xcanescens were found. The lowest increases
were observed in deltoids 'Stoneville 67' and
"C- 657". 'Ragonese 22 INTA', 'Triplo' and
"20- 82" are alternatives for growing poplar in
forest plantations and shelterbelt.Fil: Thomas, Esteban R..
Instituto Nacional de Tecnología Agropecuaria (Argentina)Fil: Garces, Anibal C.
Algunos Aspectos del Cultivo de la Marihuana (Cannabis Sativa L.)
Los experimentos se realizaron en la Granja de la Universidad tecnológica del Magdalena a altura de macetas en sombreadores. La temperatura promedio reinante, fue de 32° y una precipitación promedia de 700 mm. Bajo estas condiciones la Cannabis sativa no responde a la fertilización del fertilizante triple 14, de acuerdo a los datos estadísticos. Las plantas de la edad de 120 días se sacaron a plena luz del sol, suspendiendo que el riego para poder encontrar el material seco, el cual sirvió para el análisis estadístico. El diseño empleado fue el de block al azar con seis replicaciones y cuatro tratamientos (0, 100, 200 y 300 Kg/Ha. del fertilizante Triple 14). Aunque no existió diferencia significativa podemos recomendar a la prueba de Duncan, que la mejor dosis es la de 200 Kg/Ha. las malezas que más incidieron fueron el coquito, la verdolaga, el bleo, el meloncillo y la pringamoza. La marihuana es susceptible al hongo clasificado como Aspergillus flavus que produce en hombres y animales la Aspergilosis considerada el mayor productor de toxinas del mundo
Managing Natural Grasslands in a Changing World: Grazing Ecology Insights to Accomplish Re‐Oriented Management Expectations
Pravastatin Chronic Treatment Sensitizes Hypercholesterolemic Mice Muscle To Mitochondrial Permeability Transition: Protection By Creatine Or Coenzyme Q(10)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Statins are efficient cholesterol-lowering medicines utilized worldwide. However, 10% of patients suffer from adverse effects specially related to skeletal muscle function. Pro- or anti-oxidant effects of statins have been reported. Here we hypothesized that statins induce muscle mitochondrial oxidative stress leading to mitochondrial permeability transition (MPT) which may explain statin muscle toxicity. Thus, our aims were to investigate the effects of statin chronic treatment on muscle mitochondrial respiration rates, MPT and redox state indicators in the context of hypercholesterolemia. For this purpose, we studied muscle biopsies of the hypercholesterolemic LDL receptor knockout mice (LDLr-/-) treated with pravastatin during 3 months. Plantaris, but not soleus muscle of treated mice showed significant inhibition of respiration rates induced by ADP (-14%), oligomycin (-20%) or FCCP (-40%). Inhibitions of respiratory rates were sensitive to EGTA (Ca2+ chelator), cyclosporin A (MPT inhibitor), ruthenium red (inhibitor of mitochondria Ca2+ uptake) and coenzyme Q(10) (antioxidant), indicating that pravastatin treatment favors Ca2+ induced MPT. Diet supplementation with creatine (antioxidant) also protected treated mice against pravastatin sensitization to Ca2+ induced MPT. Among several antioxidant enzymes analyzed, only catalase activity was increased by 30% in plantaris muscle of pravastatin treated mice. Oxidized lipids, but not proteins biomarkers were identified in treated LDLr-/- plantaris muscle. Taken together, the present results suggest that chronic pravastatin administration to a model of familial hypercholesterolemia promotes mitochondrial dysfunctions in plantaris muscle that can be counteracted by antioxidants administered either in vitro (CoQ(10)) or in vivo (creatine). Therefore, we propose that inhibition of muscle mitochondrial respiration by pravastatin leads to an oxidative stress that, in the presence of calcium, opens the permeability transition pore. This mitochondrial oxidative stress caused by statin treatment also signals for cellular antioxidant system responses such as catalase upregulation. These results suggest that the detrimental effects of statins on muscle mitochondria could be prevented by co-administration of a safe antioxidant such as creatine or CoQ10.8Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2011/50400-0]Obesity and Co-morbidities Research Center (OCRC/Fapesp) [2013/07607-8]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)FAPESP fellowships [2014/11261-2, 2014/00084-2, 2014/08995-4]CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior) fellowshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Assessing land-ocean connectivity via Submarine Groundwater Discharge (SGD) in the Ria Formosa Lagoon (Portugal): combining radon measurements and stable isotope hydrology
Natural radioactive tracer-based assessments of basin-scale Submarine Groundwater Discharge (SGD) are well developed, but because of the different modes in which SGD takes place and the wide range of spatial and temporal scales under which the flow and discharge mechanisms involved occur, quantifying SGD while discriminating its source functions remains a major challenge. Yet, correctly identifying both the fluid source and composition is critical: when multiple sources of the tracer of interest are present, failure to adequately discriminate between them will lead to inaccurate attribution and the resulting uncertainties will affect the reliability of SGD solute loading estimates. This lack of reliability then extends to the closure of local biogeochemical budgets, confusing measures aiming to mitigate pollution. Here, we report a multi-tracer study to identify the sources of SGD, distinguish its component parts and elucidate the mechanisms of their dispersion throughout the Ria Formosa – a seasonally hypersaline lagoon in Portugal. We combine radon budgets that determine the total SGD (meteoric + recirculated seawater) in the system with stable isotopes in water (2H, 18O), to specifically identify SGD source functions and characterize active hydrological pathways in the catchment. Using this approach, SGD in the Ria Formosa could be separated into a net water input and another involving no net water transfer, i.e. originating in seawater recirculation through permeable sediments. The former SGD mode is present occasionally on a multiannual timescale, while the latter is a permanent feature of the system. In the absence of meteoric SGD inputs, seawater recirculation through beach sediments occurs at a rate of ~ 1.4 × 106 m3 day−1, implying the entire tidal-averaged volume of the lagoon is filtered through local sandy sediments within 100 days, or about 3.5 times a year, driving an estimated nitrogen (N) load of ~ 350 t N yr−1 into the system as NO3−. Land-borne SGD could add a further ~ 61 t N yr−1 to the lagoon. The former source is autochthonous, continuous and responsible for a large fraction (59 %) of the estimated total N inputs into the system via non-point sources, while the latter is an occasional allochthonous source, so more difficult to predict, but capable of driving new production in the system
Spitzer Infrared Spectrograph Observations of Magellanic Cloud Planetary Nebulae: the nature of dust in low metallicity circumstellar ejecta
We present 5 - 40 micron spectroscopy of 41 planetary nebulae (PNe) in the
Magellanic Clouds, observed with the Infrared Spectrograph on board the Spitzer
Space Telescope. The spectra show the presence of a combination of nebular
emission lines and solid-state features from dust, superimposed on the thermal
IR continuum.
By analyzing the 25 LMC and 16 SMC PNe in our sample we found that the IR
spectra of 14 LMC and 4 SMC PNe are dominated by nebular emission lines, while
the other spectra show solid-state features. We observed that the solid-state
features are compatible with carbon-rich dust grains (SiC, polycyclic aromatic
hydrocarbons (PAHs), etc.) in most cases, except in three PNe showing
oxygen-rich dust features. The frequency of carbonaceous dust features is
generally higher in LMC than in SMC PNe.
The spectral analysis allowed the correlations of the dust characteristics
with the gas composition and morphology, and the properties of the central
stars. We found that: 1) all PNe with carbonaceous dust features have C/O>1,
none of these being bipolar or otherwise highly asymmetric; 2) all PNe with
oxygen-rich dust features have C/O<1, with probable high mass progenitors if
derived from single-star evolution (these PNe are either bipolar or highly
asymmetric); 3) the dust temperature tracks the nebular and stellar evolution;
and 4) the dust production efficiency depends on metallicity, with low
metallicity environments not favoring dust production.Comment: The Astrophysical Journal, in pres
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Mapping The Interstellar Medium With Near-Infrared Diffuse Interstellar Bands
We map the distribution and properties of the Milky Way's interstellar medium as traced by diffuse interstellar bands (DIBs) detected in near-infrared stellar spectra from the SDSS-III/APOGEE survey. Focusing exclusively on the strongest DIB in the H band, at lambda similar to 1.527 mu m, we present a projected map of the DIB absorption field in the Galactic plane, using a set of about 60,000 sightlines that reach up to 15 kpc from the Sun and probe up to 30 mag of visual extinction. The strength of this DIB is linearly correlated with dust reddening over three orders of magnitude in both DIB equivalent width (Wpm) and extinction, with a power law index of 1.01 +/- 0.01, a mean relationship of W-DIB/A(v) = 0.1 angstrom mag(-1) and a dispersion of similar to 0.05 angstrom mag(-1) at extinctions characteristic of the Galactic midplane. These properties establish this DIB as a powerful, independent probe of dust extinction over a wide range of Av values. The subset of about 14,000 robustly detected DIB features have a W-DIB distribution that follows an exponential trend. We empirically determine the intrinsic rest wavelength of this transition to be lambda(0) = 15 272.42 angstrom and use it to calculate absolute radial velocities of the carrier, which display the kinematical signature of the rotating Galactic disk. We probe the DIB carrier distribution in three dimensions and show that it can be characterized by an exponential disk model with a scale height of about 100 pc and a scale length of about 5 kpc. Finally, we show that the DIB distribution also traces large-scale Galactic structures, including the Galactic long bar and the warp of the outer disk.NSF Astronomy & Astrophysics Postdoctoral Fellowship AST-1203017NSF AST-1109665Alfred P. Sloan FoundationNational Science FoundationU.S. Department of Energy Office of ScienceUniversity of ArizonaBrazilian Participation GroupBrookhaven National LaboratoryUniversity of CambridgeCarnegie Mellon UniversityUniversity of FloridaFrench Participation GroupGerman Participation GroupHarvard UniversityInstituto de Astrofisica de CanariasMichigan State/Notre Dame/JINA Participation GroupJohns Hopkins UniversityLawrence Berkeley National LaboratoryMax Planck Institute for AstrophysicsMax Planck Institute for Extraterrestrial PhysicsNew Mexico State UniversityNew York UniversityOhio State UniversityPennsylvania State UniversityUniversity of PortsmouthPrinceton UniversitySpanish Participation GroupUniversity of TokyoUniversity of UtahVanderbilt UniversityUniversity of VirginiaUniversity of WashingtonYale UniversitySpanish Ministry of Economy and Competitiveness AYA-2011-27754McDonald Observator
The effect of laser pan-retinal photocoagulation with or without intravitreal bevacizumab injections on the OCT-measured macular choroidal thickness of eyes with proliferative diabetic retinopathy
OBJECTIVES: To investigate the effect of laser pan-retinal photocoagulation with or without intravitreal bevacizumab injections on macular choroidal thickness parameters in eyes with high-risk proliferative diabetic retinopathy. METHODS: High-risk proliferative diabetic retinopathy patients undergoing laser treatment were prospectively enrolled in this study. One eye was randomly selected for laser treatment combined with bevacizumab injections, study group, whereas the corresponding eye was subjected to laser treatment alone, control group. Spectral-domain optical coherence tomography with enhanced depth imaging was used to measure the macular choroidal thickness prior to and 1 month after treatment. Measurements in both groups were compared. Clinicaltrials.gov: NCT01389505. RESULTS: Nineteen patients (38 eyes) with a mean±standard deviation age of 53.4±9.3 years were evaluated, and choroidal thickness measurements for 15 patients were used for comparison. The greatest measurement before treatment was the subfoveal choroidal thickness (341.68±67.66 μm and 345.79±83.66 μm for the study and control groups, respectively). No significant difference between groups was found in terms of macular choroidal thickness measurements at baseline or after treatment. However, within-group comparisons revealed a significant increase in choroidal thickness parameters in 10 measurements in the study group and in only 5 temporal measurements in the control group when 1-month follow-up measurements were compared to baseline values. CONCLUSIONS: The macular choroidal thickness does not appear to be significantly influenced by laser treatment alone but increases significantly when associated with bevacizumab injections in patients with proliferative diabetic retinopathy and macular edema. Because bevacizumab injections reduce short-term laser pan-retinal photocoagulation-induced macular edema, our findings suggest that the choroid participates in its pathogenesis
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